Indices of working memory and planning were also associated with ADHD after controlling for potential confounders (ps < 0.03). Mediation analyses revealed that poor working memory performance mediated the link between exposure to early institutionalization and higher scores of both inattention and impulsivity. These results replicate and extend the findings that we reported in the BEIP sample at age 8 years. Together, they suggest that compromised working memory is a key mechanism that continues to explain the strikingly high levels of ADHD in late childhood among children institutionalized in early life. Interventions targeting working memory may help to prevent ADHD among children exposed to institutional care.Children who are raised in institutions show severe delays across multiple domains of development and high levels of psychopathology, including attention deficit/hyperactivity disorder (ADHD). Low performance in executive functions (EFs) are also common in institutionally reared children and often do not remediate following improvements in the caregiving environment. ADHD symptomatology also remains elevated even after children are removed from institutional care and placed in families. We investigate whether poor EF is a mechanism explaining elevated rates of ADHD in children reared in institutional settings in the Bucharest Early Intervention Project (BEIP). In the current study, we examine the potentially mediating role of poor EF in the association between institutionalization and symptoms of ADHD at age 12 years. A total of 107 children were assessed with the Cambridge Neuropsychological Test Automated Battery (CANTAB) on working memory, set-shifting and planning. We also obtained concurrent teacher reports on their levels of ADHD symptoms (inattention and impulsivity separately). Institutionalization strongly predicted elevations in symptoms of inattention and impulsivity at age 12 years ( Considerable evidence indicates that early adverse environments can render children vulnerable to various psychiatric disorders that develop later in life . The linA particularly egregious form of early adversity is institutional rearing, which currently impacts approximately eight million children around the world . InstituThese disruptions in EF might represent a developmental pathway linking early institutionalization to the onset of some forms of psychopathology. The prevalence of mental health problems is unusually high in children reared in institutions, especially attention deficit/hyperactivity disorder ADHD; . CurrentMechanisms linking institutionalization to ADHD have included multiple manifestations of atypical brain structure and function , 2014b. In the current study, we aimed to replicate and extend our previous findings at age 8 by exploring the potentially mediating role of EFs in the association between institutionalization and symptoms of ADHD at age 12. Given ongoing development of EFs during early adolescence , and givThe study participants were children from our longitudinal investigation  who were recruited in infancy from institutions in Bucharest, Romania, and randomized to either a care-as-usual-group (CAUG) who continued to live in the institutions, or a foster care group (FCG) whom we placed in foster families that we recruited and offered support until children were 42 months old. A third community control group of never institutionalized (NIG) children was recruited at the same time with the institutionalized children through General Practitioner offices. At 12 years, 107 participants in the BEIP were assessed with the Cambridge Neuropsychological Test Automated Battery (CANTAB) on working memory, set-shifting, and planning and we also obtained teacher reports on their levels of ADHD symptoms (with separate measurements for inattention and impulsivity).Table 1 and show significant differences in birth weight. Mean birth weight in the institutionalized children was significantly lower than in the community controls  = -6.58; p < 0.001). Therefore we included birth weight as a covariate in all subsequent analyses.Demographic characteristics for the participants in the two groups  are presented in We obtained teacher reports on children’s symptoms of inattention and hyperactivity using the Health and Behavior Questionnaire HBQ; , a questThe CANTAB was used to measure working memory, planning, and set-shifting. The CANTAB contains behavioral subtests that have been widely used with typically developing children, at-risk children, children with ADHD, and adults . The CANDelayed Matching to Sample (DMS) is a short term memory task in which the child is presented with a stimulus pattern and then needs to select a matching pattern from a series of four patterns shown below the stimulus. Trials are either simultaneous (both the stimulus and the four choices are shown on the screen at the same time), with a zero-second delay (the stimulus disappears just before the choices are presented), or with a delays of 4000 or 12000 ms. The main outcome variables are the percentage of correct trials and latency of response for each type of trial.Paired Associates Learning (PAL) subtest assesses spatial working memory and new learning. Six to eight boxes are presented sequentially on the screen, with some or all containing a different pattern. The patterns are then shown again in the middle of the screen, one at a time and in random order, and the child has to touch the box that contained the pattern. The difficulty increases with the number of patterns contained in the boxes. Outcome variables include stages completed at first trial, total stages completed, and memory score .Spatial Working Memory (SWM) tests the ability to retain spatial information across a delay and to manipulate remembered items in working memory. A number of 3–8 colored boxes are shown on the screen and the subject is invited, by process of elimination, to find a blue token in each of these boxes and use it to fill up an empty column on the right of the screen. Variables of interest are total errors , between errors , within errors , and strategy .Stockings of Cambridge (SOC) is a planning task derived from the Tower of London test . The chiIntra-Extra Dimensional Set Shift (IED) assesses rule acquisition and reversal and attention flexibility. Two stimuli (one correct and one incorrect) are displayed on the computer screen. Stimuli initially represent only one category , then two categories . Participants learn to select the correct categories based on instantaneous feedback from the computer, but the stimuli and/or rules are changed after a specific number of correct responses. The initial shifts in correct stimuli are intra-dimensional  and later become extra-dimensional, requiring a category shift . Performance is assessed based on, among other indicators, number of stages completed and number of errors made.Ethics approval was obtained from the University of Bucharest’s Ethics Committee, as well as the Institutional Review Boards (IRBs) of the US universities to which the project’s Principal Investigators were affiliated. As the children approached 12 years of age, the families were invited to come for assessments to our laboratory in Bucharest. Consent forms were signed by the legal guardians, and verbal and written assent was also obtained from the children. The CANTAB was administered during one of the lab sessions. The HBQs were distributed to the teachers. Both the families and the teachers were compensated commensurate to the amount of time involved and deemed appropriate in consultation with local staff.To test our hypothesis that EF mediated the link between exposure to institutionalization and ADHD, we first sought to establish links between the predictor and each of the two dependent variables , as well as associations between our proposed mediators  and both the predictor and the dependent variables. As a final step, we conducted two sets of mediation analyses (one for inattention and one for impulsivity) and calculated mediation effects  only for the EF variables that were significantly linked to the predictor and the dependent variables following recommendations from t(79) = 0.54, p = 0.59 for inattention; t(79) = 0.50, p = 0.62 for impulsivity, which is congruent with parent reports of children’s symptomatology in this sample (N = 73) and the never institutionalized group . The same approach has been employed in several other BEIP studies that have examined mechanisms linking institutionalization to elevations in ADHD  = 19.93, p < 0.001, and impulsivity, F = 8.80, p = 0.004, compared to children in the community group.History of institutional rearing predicted scores on both ADHD scales. As shown in Children exposed to institutional rearing had worse performance than those who had never been institutionalized on multiple EF indices in each of the five CANTAB tasks, including all three tests of working memory, planning, and set-shifting , PAL first trial memory score , SWM strategy score , SWM total errors , and SOC problems solved in minimum moves , and also between impulsivity and PAL first trial memory score , SWM strategy score , SWM total errors , and SOC problems solved in minimum moves .After controlling for birth weight and gender, several working memory and planning indices continued to predict ADHD levels. Specifically, associations remained significant between inattention and DMS percent accuracy 12000 ms  when these working memory variables were included as mediators. By contrast, when the planning index was included as a mediator, the indirect effect of institutionalization on inattention was not statistically significant . These findings suggest that the link between exposure to institutionalization and inattention is mediated by working memory, and not explained by planning.In predicting inattention, we first included as mediators the four working memory variables jointly , and then the planning index  as sole mediator. The indirect effect of exposure to institutionalization on inattention through the working memory indices was significant . The total effect of institutionalization in predicting inattention was attenuated by 48.6% to non-significance level  with the inclusion of the working memory indices as joint mediators. In contrast, the indirect effect of institutionalization in the prediction of impulsivity when the SOC variable was entered as mediator was statistically non-significant . These results suggest that the link between exposure to institutionalization and impulsivity is, as with inattention, explained by performance in working memory and cannot be attributed to the children’s planning ability.Likewise, in predicting impulsivity, we first included as mediators three working memory variables jointly , then the planning index  as sole mediator. The indirect effect of exposure to institutionalization on impulsivity through the working memory indices was significant . The total effect of exposure to institutionalization in predicting impulsivity was attenuated by 66.5% to non-significance level (Children with histories of institutional rearing continue to display elevated symptoms of ADHD and poor EF performance in the pre-pubertal period. In the current study, we show that EF mediates the link between institutionalization and symptoms of both inattention and impulsivity, which provides support for the hypothesis that low cognitive abilities represent a distinct pathway through which early institutional care exerts a persistent impact on mental health problems. As we expected, children reared in institutions had higher ADHD symptomatology and worse performance across EF tasks compared to a control group (for detailed results on the EF, see The results in the current study replicate and extend findings from other studies that have tested samples of previously institutionalized and adopted children of comparable ages to the children in our study. Specifically, our finding that previously institutionalized children exhibit markedly elevated rates of inattention and impulsivity as reported by their teachers is consistent with caregiver reports obtained through a structured interview in the BEIP  and withAdditionally, we replicate and extend our previous findings on the mediating role of EF in the link between early institutional care and ADHD symptomatology in middle childhood . Here, wHow exactly reduced working memory exerts influence on the development of ADHD is difficult to answer given that multiple pathways resulting from interplays between individual predispositions and environmental adversities are likely to be involved  and instPlanning ability, although impacted by institutionalization and linked to ADHD, was not a construct that explained ADHD symptoms in our current study, which is consistent with our BEIP findings at age 8 years. It is possible that planning, which is thought to be a more sophisticated problem-solving cognitive skill, is not affected by institutionalization in the same manner as other more fundamental EFs like working memory. There is evidence suggesting that working memory and inhibition are more central processes that help toward the development of most of the other EFs , and it There are several noteworthy clinical and theoretical implications regarding the findings in the current study. First, caregivers and specialists should be informed that many of the children who had been reared in institutions will exhibit high levels of ADHD symptoms that are likely to persist throughout childhood and beyond. Foster and adoptive parents need to become aware of the enduring neurocognitive deficits and impulsive/inattentive manifestations that many of these children will show across settings. Second, there is potential for interventions to be designed that may decrease these symptoms by improving children’s cognitive abilities, at least their working memory. Indeed, there are programs that have proved their efficacy in addressing ADHD problems through working memory training , althougThe strengths of the current study include a longitudinal sample from an RCT with a rarely studied population that had been exposed to institutional rearing, some from as early as 6 months of age, a robust mediation model that allows testing a causal understanding on ADHD while controlling for confounders, and good retention rates in a sample of highly vulnerable adolescents recruited more than a decade ago.Our study should also be discussed in terms of its limitations. First, we included concurrent measurements of EF and ADHD, which may pose some limitations in inferring causality. Second, we made use of questionnaires as opposed to interviews for measuring ADHD symptoms. Nevertheless, teacher reports are reliable instruments in measuring levels of symptomatology, particularly of externalizing nature  and haveThis study identified poor working memory as a mediator of the association between institutional rearing and ADHD symptoms of inattention and impulsivity at 12 years of age in children who, during their early childhood, grew up in institutions. Mental health problems, ADHD in particular, are a public health concern at global level and our current findings have the potential to inform specialists on some of the neuropsychological mechanisms to psychopathology during early adolescence so that interventions can be effectively implemented to reduce maladaptation and increase chances of academic success and optimal social and occupational functioning.CN, NF, and CZ designed research; FT performed research; FT, MS, and KM analyzed data; FT, MS, KM, CN, NF, and CZ wrote the paper.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer VS and the handling Editor declared their shared affiliation, and the handling Editor states that the process nevertheless met the standards of a fair and objective review.


The mechanism by which paracetamol may modulate the increased risk of developing ADHD is currently unknown. We have conducted an epigenome-wide association study (n = 6211 CpGs) associated with prenatal exposure to paracetamol for more than 20 days in children diagnosed with ADHD compared to controls. In addition, these samples were differentially methylated compared to samples with ADHD exposed to paracetamol for less than 20 days (n = 2089 CpGs) and not exposed to paracetamol (n = 193 CpGs). Interestingly, several of the top genes ranked according to significance and effect size have been linked to ADHD, neural development, and neurotransmission. Gene ontology analysis revealed enrichment of pathways involved in oxidative stress, neurological processes, and the olfactory sensory system, which have previously been implicated in the etiology of ADHD.Analyses identified significant differences in DNA methylation  contains supplementary material, which is available to authorized users. Attention-deficit/hyperactivity disorder (ADHD) is a common childhood disorder defined by inattention, hyperactivity, and impulsivity, which impair normal functioning and development. It is one of the most prevalent psychiatric disorders of childhood affecting approximately 5% of children worldwide, often continuing into adulthood . ADHD isSeveral epidemiological studies have shown that exposure to a range of putative environmental risk factors are associated with ADHD, particularly during the prenatal and perinatal period. However, these factors can only be regarded as correlates because, at present, convincing evidence that the associations reflect causal relationships have not been established . ADHD isRecently, five epidemiological studies have revealed a consistent association between long-term exposure to paracetamol (acetaminophen) during pregnancy and ADHD symptoms –21 and aIn this study, we aimed to assess whether epigenetic differences are associated with prenatal exposure to paracetamol and development of ADHD. To do this, we have conducted an epigenome-wide association study (EWAS) in samples selected from the Norwegian Mother and Child Cohort (MoBa) and investigated whether long-term prenatal exposure to paracetamol was associated with DNA methylation changes in cord blood and clinical ADHD diagnoses recorded in the Norwegian Patient Registry (NPR) from 2008 to 2014.The samples in this study were selected to enable a systematic investigation of the association between DNA methylation and paracetamol exposure in children with and without ADHD Table . First, Next, we investigate the synergistic effect of prenatal exposure to paracetamol on DNA methylation differences in children with ADHD. To do this, we stratified the analyses on samples exposed to paracetamol  were driven by outliers.Comparison of the samples exposed to paracetamol with ADHD (synergistic effect group) to each of the other three groups did not identify any differential DNA methylation below the significance threshold . However, analyses contrasting sporadic and long-term paracetamol use revealed that exposure to paracetamol for ≥20 days was associated with DNA methylation differences in samples with ADHD. These samples showed differential DNA methylation compared to the control group after FDR correction in a large number of CpG sites , voltage channels . In addM1 [REST , ZNRF1 [T [ZNRF1 , RabGEF1[RabGEF1 , and CUXF1 [CUX1 ), neurotX1 [SYN2  and DDAH2 [DDAH1 ; Fig. 1ed CACNG8 ), and peGene ontology (GO) analyses of the top 100 significantly differentially methylated genes ranked on the combined score identified enrichment of pathways involved in oxidative stress among the genes showing increased DNA methylation . The majority involved small differences in DNA methylation. Sensitivity analyses showed that outliers in this group influenced a small proportion (11.2%) of the differentially methylated CpGs. It is not possible to differentiate the influence of technical outliers from extreme DNA methylation values reflecting paracetamol dosage-effect (high number of days of exposure) associations. To increase biological relevance, the analyses and interpretation of the results were based on the genes displaying significant and the largest differences in DNA methylation. Several of the top ranked genes have previously been linked to not only ADHD but also neural development and neurotransmission. These are categories involved in the brain development and function and are also enriched among genes genetically associated with ADHD . ADHD isInterestingly, we identified more differentially methylated positions when comparing the long-term exposed samples to sporadic exposed samples than to unexposed samples with ADHD. Whereas this observation is difficult to explain, it could reflect the fact that dose-response relationships are usually not linear. Unfortunately, it is difficult to model and monitor a dose effect and timing during pregnancy due to the way the MoBa questionnaires were designed and completed. Future studies including a larger sample should investigate whether this trend remains.The results presented in this study should be interpreted in light of several limitations. Although this study is based on one of the largest prospective birth cohorts in the world, the number of samples possessing both clinical ADHD diagnoses and long-term prenatal exposure to paracetamol was relatively small. Hence, the association between paracetamol and ADHD should be replicated in a larger set of samples. We report DNA methylation differences in cord blood samples, and whether these differences also reflect changes in the brain needs to be established. Although the analyses and results were focused on differentially methylated genes with large effect sizes, the effect on gene expression needs to be explored. Heritable impulsive traits are associated with paracetamol use during pregnancy . Future There are also several strengths that should be taken into account. We used a clinical diagnosis of ADHD given by specialists obtained through linkage to the NPR. Although registry-based diagnoses of ADHD has been used as outcome in a number of previous Scandinavian studies on ADHD, including the abovementioned Danish birth cohort study of paracetamol use during pregnancy and ADHD , they haThis study identified altered DNA methylation differences at genes involved in oxidative stress, neural transmission, and olfactory sensory pathways associated with long-term exposure to paracetamol during pregnancy in children diagnosed with ADHD. These results suggest that in individuals susceptible to ADHD, prenatal long-term exposure to paracetamol is associated with DNA methylation changes. That is, individuals susceptible to ADHD respond differently compared to controls to long-term paracetamol exposure during development. This is compatible with the epidemiological evidence of the increased risk of developing ADHD with long-term paracetamol exposure. Further, these results lend novel insights into the etiology of ADHD and may serve as disease biomarkers in blood. Future developments should also investigate the functional impact of these DNA methylation differences on neural development in model systems.The samples were obtained from MoBa, which is a large prospective population-based pregnancy cohort study conducted by the Norwegian Institute of Public Health . ParticiInformation about paracetamol use (ATC code: N02BE01) was based on three questionnaires . In order to minimize potential confounding by gestational age, only term children were included in the study (≥37 weeks). Samples with no reported co-medication together with paracetamol were selected to be certain that the number of days of use corresponded to paracetamol use. We defined long-term use as use of paracetamol for 20 days or more during pregnancy based on previous studies . MoreoveInformation about the children’s ADHD diagnoses from 2008 to 2014 was obtained from the NPR. From 2008, all hospitals owned and funded by the government and outpatient clinics report individual-level diagnoses given by specialists according to the 10th revision of the International Classification of Disease (ICD-10). Children registered with an ICD-10 diagnosis of hyperkinetic disorder (HKD)  between 2008 and 2013 were identified and defined as having ADHD. HKD requires the combination of inattentive and hyperactive symptoms and thus corresponds to the combined subtype in the Diagnostic and Statistical Manual (DSM) system , 52.n = 384) were selected to allow a cohort study design with 96 samples in each of the four categories (Table The participants included in this study (es Table : (1) unehttp://www.r-project.org/), and the raw data were preprocessed using the approach implemented in RnBeads v.1.2.1 [n = 29,233), probes with overlapping SNPs in any of the bases in the target sequence , and probes and samples with unreliable measurements   were removed. Background subtraction was performed using noob.methylumi [β values  were normalized using BMIQ [n = 9489) and non-CpG probes (n = 2458) were removed, resulting in a final data set consisting of 390,787 probes and 377 samples. Cell-type proportions  for each sample were estimated using the Houseman reference-based approach [FlowSorted.CordBloodNorway.450K), which we have recently established [Bisulfite conversion of 500-ng cord blood DNA was done using the EZ-96 DNA Methylation-Gold Kit (Zymo Research) according to the manufacturer’s instructions. The samples were randomly located on 96-well plates to minimize potential batch effects related to bisulfite conversion. DNA methylation status was assessed using the Infinium HumanMethylation 450 BeadChip (Illumina). All analyses were carried out using the R programming language , which are more statistically valid for differential DNA methylation analyses than β values [All statistical tests were performed on the β values . To idenβ values  and the sporadic  or long-term  groups and used similar comparison groups as above. This enabled exploration of the epidemiological evidence that long-term exposure during pregnancy is associated with development of ADHD [We performed three sets of analyses to explore the relationship between prenatal exposure to paracetamol and DNA methylation differences in children with ADHD Table . First,  of ADHD –22.p values for each region were obtained by combining the uncorrected p values for each CpG in the region [All analyses were conducted on the CpG site and region levels. Regional analysis was performed on predefined genomic regions . Briefly, aggregated e region . To adjue region . Sex, smp values from the linear model were ranked for all sites. Then, the rank for each of the three measures was aggregated into a combined score. The differentially methylated CpGs and regions were ranked according to this combined score.Analysis was also done based on a combined score of statistical significance and effect size to increase the biological relevance of the observed differences in DNA methylation as implemented in RnBeads . Brieflysva R package [Surrogate variable analyses were performed to search for unmeasured sources of variation in DNA methylation confounding DNA methylation differences between groups. Specifically, surrogate variables were estimated directly from the DNA methylation data using the  package  with defGOstats package based on the top 100 differentially methylated genes ranked according to the combined score (effect size). Both over- and under-representation of GO terms were tested with a standard hypergeometric test among genes showing differential DNA methylation.Gene ontology (GO) analysis was performed using the Additional file 1: Table S1.Significantly methylated CpGs between long-term exposed samples with ADHD and controls. (XLSX 1646 kb)Additional file 2: Table S2.Significantly methylated CpGs between long-term exposed samples with ADHD and sporadically exposed samples with ADHD. (XLSX 585 kb)Additional file 3: Table S3.Significantly methylated CpGs between long-term exposed samples with ADHD and unexposed samples with ADHD. (XLSX 101 kb)Additional file 4: Figure S1.p values associated with differences in DNA methylation in long-term exposed children with ADHD. Q-Q plots of the observed versus expected p values from the comparisons DNA methylation in cord blood from long-term exposed children with ADHD  to controls , sporadically exposed children with ADHD  and unexposed children with ADHD . The corresponding histograms of the nominal p values for each of the three comparisons display an enrichment of small p values. (PDF 887 kb)Enrichment of small


Attention deficit hyperactivity disorder (ADHD) is a childhood-onset neurological disorder that often continues into adult age. Stimulants medication are the mainstay of treatment, however, in the recent years, there has been a lot of studies conducted to understand the effectiveness and feasibility of mindfulness-based cognitive behavioral therapy for treatment of attention deficit hyperactivity disorder in children and adults. In this article, we have reviewed 17 articles to look for the beneficial effects of such therapy in adults. Overall, we found that there is a clear beneficial effect of such therapies, especially when used in adjunct with stimulant medication and may increase overall compliance. For better understanding, we suggest that large, well-designed studies should be conducted with robust strategies, allowing more comparison studies with the better analytical outcome. Attention deficit hyperactivity disorder (ADHD) is a disorder of neurodevelopment in children with high persistence into adulthood. ADHD manifests with high levels of inattention, impulsiveness, and hyperactivity. This condition affects social, academic and occupational functioning. Sign and symptoms of adult ADHD include difficulty prioritizing, organizing, and completing tasks, variable attention to detail, hyperactivity, and reduced impulse control. These deficits often lead to adverse psychosocial outcomes including academic failure, dropping out of school, unintended pregnancy, sexually transmitted infections (STI) exposure, and criminal behavior (e.g.: increased risk of traffic violations). Furthermore, such individuals have lower levels of educational and occupational achievement . HyperacGiven these, the fifth edition of the Diagnostic and Statistical Manual was released in May 2013 and replaced the previous version, the text revision of the fourth edition (DSM-4). DSM-5 included significant changes in the diagnostic criteria for ADHD and increased the guidance for diagnosing ADHD in adults: (1) Symptoms can now occur at age of 12 years rather than by age six years; (2) Several symptoms now need to be present in more than one setting, than just causing some impairment in more than one setting; (3) New descriptions were added to show the symptoms that might look at older ages; and (4) for adults and adolescents age of 17 years or older, only five symptoms are needed instead of six for younger children [The standard of care for adults has evolved primarily from studies in children and the medications used in adults are the same as those employed in children and adolescents with ADHD. For adolescents of 12–18 years of age, the primary care clinician should prescribe Food and Drug Administration (FDA) approved medications for ADHD, with the assent of the adolescent and may prescribe behavior therapy as a treatment for ADHD, although preferably both medication and behavior therapy should be used together . FDA-appAs such, there are a number of reasons for pursuing alternative or adjunctive treatments for ADHD in adults: some patients experience side effects of the stimulant medications use; others experience only a 30% reduction in symptoms; such stimulants are less effective in adults than in children and some patients are not willing to undergo pharmacological treatment. Because many patients undergoing pharmacotherapy still experience functional deficits related to decreased self-monitoring, inattention and mood disturbance. Interventions such as mindful awareness practices that directly address these problems could be used as adjuvant treatments .Mindfulness-based interventions are a type of cognitive training involving various strategies to improve attention, affective self-regulation, tranquility and better quality of life in a healthy population . With thSeveral recent studies in adult ADHD samples provide promising preliminary support for mindfulness meditation training. There is emerging evidence that mindfulness meditation employed as a neurobehavioral intervention can help ADHD patients to regulate brain functioning and thereby improve the conscious direction of attention and emotional control .We reviewed around 16 studies in recent years on the effects of mindfulness-based cognitive therapies in adults, the majority of which show a clear beneficial effect on ADHD symptoms in adults , 33,34. Another study conducted in 2015 reported that mindfulness-based cognitive therapy (MBCT) resulted in a significant reduction of ADHD symptoms and the symptom improvement was calculated both by investigators and by self-reported questionnaires . The datAdult ADHD can have a huge personal and economic impact. There is strong evidence that medications can be effective in adults, decreasing the symptoms and their sequelae. However, there remains a great need for evidence-based psychosocial interventions to serve as adjunct or alternative treatment for individuals intolerant or not desiring pharmacotherapy. Mindfulness-based cognitive therapy is an effective intervention and can be administered in an economically-feasible group format. Some of the limitations of studies to date include small sample size, single center enrollment, lack of follow-up and lack of control groups. There is a clear need for further research in this area.


Broadly neutralizing antibodies (bnAbs) to HIV delineate vaccine targets and are prophylactic and therapeutic agents. Some of the most potent bnAbs target a quaternary epitope at the apex of the surface HIV envelope (Env) trimer. Using cryo-electron microscopy, we solved the atomic structure of an apex bnAb, PGT145, in complex with Env. We showed that the long anionic HCDR3 of PGT145 penetrated between glycans at the trimer 3-fold axis, to contact peptide residues from all three Env protomers, and thus explains its highly trimer-specific nature. Somatic hypermutation in the other CDRs of PGT145 were crucially involved in stabilizing the structure of the HCDR3, similar to bovine antibodies, to aid in recognition of a cluster of conserved basic residues hypothesized to facilitate trimer disassembly during viral entry. Overall, the findings exemplify the creative solutions that the human immune system can evolve to recognize a conserved motif buried under a canopy of glycans. •Apex binding antibody PGT145 engages all three gp120 protomers simultaneously•Epitope recognition is chemical-feature specific•PGT145-class antibodies exhibit structural features that reflect bovine antibodies•PGT145-class antibody maturation is dependent on structural stabilization of HCDR3 Broadly neutralizing antibodies of the PGT145-family target the HIV-1 Env trimer apex via a long β-hairpin HCDR3, but the molecular basis of recognition is unknown. Using cryoEM, Lee et al. (2017) reveal how PGT145 binds its quaternary epitope and the importance of HCDR2 evolution despite its lack of contacts with Env. Numerous antibodies that target and neutralize a broad range of different human immunodeficiency virus (HIV) isolates have been found in chronically infected HIV donors. Some of these bnAbs inhibit HIV Env with remarkable breadth and potency by recognizing conserved “supersites” of vulnerability . One of 50) and CAP256-VRC26.25 , in particular, are remarkably potent , and a cluster of positively charged amino acids around the trimer 3-fold symmetry axis . In thisy potent .Partial descriptions of paratope-epitope interactions have been obtained using epitope scaffolds with PG9 , PG16 P, and theApex bnAbs discovered so far can be grouped according to their heavy chain (HC) complementarity determining region (CDR) 3 topology: (1) PG9-like with—or predicted to have—a hammerhead motif ; or (2) The trimer-specific PGT145 is one of the few antibodies with which we could previously extract cleaved wild-type JR-FL E168K EnvΔCT trimers from cell membranes A Blattn. PGT145 71dWDFD74 insertion in HFR3, which is critical for neutralizing activity  (8 B-isomer (M8B) indicating that the terminal Man(α1-2) residue of the D3 arm may sterically clash with PGT145-family Fabs. These data suggested that not only the correct glycoform, but also close spacing of glycans is essential for PGT145 binding.Previously, glycan arrays failed to detect PGT145 binding across a wide range of glycans . Here, wan (M8C) D–S3F, bu2 . PGT145 most prominently interacted with a single N160 glycan (N160glycan1), less extensively with a second N160 glycan (N160glycan2), and likely not at all with the third N160 glycan (N160glycan3) GlcNAc(β1-2/4/6) branching units would likely clash with PGT145. Thus, the mode of N160 glycan recognition differed from that of the PG9-like antibodies, in which the N160 glycan branches bury into a pocket formed by the hammerhead-shaped HCDR3 and the LCDRs  from 0.87 to 0.96  are largely restricted to interactions between the tip of HCDR3 with the C-strand of V1/V2 and the C1 region near the base of V1 including K121  of ∼70% or higher  and D100rHCDR3. The R99A paratope substitution had the second largest increase in PGT145 IC50 against all three pseudoviruses tested  or 6-residue HCDR2 (52S-H-E-G-D-K54) stabilization motif back into inferred-germline  PGT145 partially rescued the neutralizing activity of PGT145 iGL variants (LCDR1 (9 of 18 MAbs) when mutated to alanine in PGT145 resulted in a large drop in neutralization  that binds the HC of human Fabs A and S2BON 1.4b1 . The BG5ON 1.4b1   and 3BNC117 Fab (4JPV) were used as templates to generate an initial atomic model using the Modeller plug-in in UCSF Chimera . The resPGT143 and PGT144 Fabs were concentrated to 4-24 mg/mL. Fab samples were screened for crystallization using the 384 conditions of the JCSG Core Suite at both 277 and 293 K using the TSRI/IAVI/JCSG robotic Crystalmation system as described previously . Data coSPR analysis of PGT145 Fab binding to His-tagged BG505 SOSIP trimers was analyzed on a Biacore 3000 instrument at 25°C. Glycan knockout mutants were expressed in HEK293F cells unless otherwise indicated. All trimers were immobilized on the chip by His-tag capture, as previously described . To studFor pseudovirus production, we cotransfected HEK293T or 293S cells with an Env encoding and an Env-deficient backbone (pSG3DEnv) plasmids using Fugene 6 (1:2 ratio). Pseudoviruses were harvested 48–72 hr post-transfection, filtered, and titrated for use in neutralization assays. Neutralization was measured in TZM-bl target cells, as described previously  Supplem.mAbs were screened on a custom high mannose array, consisting of 9 mannosides and 1 control sialylated N-glycan. The 10 amine-linked glycans were covalently immobilized onto custom NHS-ester dendron functionalized glass microscope slides . To assess mAb binding, the antibodies were pre-mixed with the detection antibody (anti-human-IgG R-PE). Following 15 min, the pre-complexed antibodies were applied directly to the slide surface and allowed to incubate for 1 hr and then washed. Washed arrays were dried by centrifugation and then scanned for RPE signal on a confocal microarray scanner .50 values of PGT145 from 135 strains was employed for linear regression analysis. Strains with IC50 > 10 μg/mL were classified as escape. Multiple sequence alignment was performed by MUSCLE using default parameters (TZM-bl neutralization assay derived ICrameters . By comprameters . For eacrameters  in pythorameters .J.H.L, R.A., and J.-P.J. designed the project. J.H.L. performed the EM work and structural analysis. J.-P.J. and L.K. performed the crystallization studies. J.H.L. and C.A.C. performed atomic modeling of the EM structures. R.A., C.S., D.S., and M.P. performed the neutralization assays. A.Y. and P.J.K. performed the SPR studies. R.M. performed the glycan array assays. N.C.W. performed the linear regression analysis. T.N. and C.B. provided reagents. J.H.L., R.A., P.J.K., D.R.B., and A.B.W. analyzed the data. R.A. contributed to figure generation. J.H.L., A.B.W., D.R.B., and I.A.W. wrote the manuscript. All authors were asked to comment on the manuscript.


EP300 (histone acetyltransferase p300), we conducted resequencing of a 108.9 kb gene region of EP300 in 80 unrelated Tibetans. The allele-frequency and haplotype-based neutrality tests detected signals of positive Darwinian selection on EP300 in Tibetans, with a group of variants showing allelic divergence between Tibetans and lowland reference populations, including Han Chinese, Europeans, and Africans. Functional prediction suggested the involvement of multiple EP300 variants in gene expression regulation. More importantly, genetic association tests in 226 Tibetans indicated significant correlation of the adaptive EP300 variants with blood nitric oxide (NO) concentration. Collectively, we propose that EP300 harbors adaptive variants in Tibetans, which might contribute to high-altitude adaptation through regulating NO production.The genetic adaptation of Tibetans to high altitude hypoxia likely involves a group of genes in the hypoxic pathway, as suggested by earlier studies. To test the adaptive role of the previously reported candidate gene  Tibetans are well adapted to high-altitude environments, in which the key environmental stress is hypobaric hypoxia. Physiologically, Tibetans show blunted responses to high altitude hypoxia, with low pulmonary vasoconstrictor response and low hemoglobin concentration compared with lowlanders moving to high altitude . Previou and its negative regulator EGLN1 are considered key genes responsible for Tibetan adaptation (HMOX2), with Tibetan-enriched adaptive mutations of HMOX2 shown to cause more efficient breakdown of heme during hemoglobin metabolism (Hypoxia inducible factor 2α aptation . Comparetabolism . HoweverEP300) is among the candidate genes showing signals of selection (EP300 is located on human chromosome 22 (22q13.2), spanning about 88.9 kb with 31 exons  transactivation through specific recognition and hydroxylation of asparagine   . Furtherportance .EP300 in Tibetan adaptation to high altitude hypoxia, we resequenced the entire genomic region of EP300. Neutrality tests suggested a signal of positive Darwinian selection on EP300 in Tibetans. Genetic association analysis indicated the involvement of EP300 in regulating nitric oxide production.To understand the potential role of We resequenced a 108.9 kb genomic fragment of 47 unrelated Tibetan individuals, with sample details reported in previous study . We alsoFST was calculated between Tibetans and the three lowland reference populations from the 1000 Genomes Project, which included 103 Han Chinese (CHB), 99 Europeans (CEU), and 108 Africans (YRI). Tajima's D-test was also performed to detect selection (From the resequencing data (108.9 kb) of 80 Tibetans, we obtained 250 sequence variants. For quality control, we removed variants showing a significant deviation from the Hardy-Weinberg Equilibrium (HWE < 0.000 1) and variants with an excessive missing genotype rate (MGR > 0.05). A total of 185 variants remained after the filtering process. Following the methodology of election .For haplotype-based selection tests, the iHS score was calculated for each variant in Tibetans using selscan  based onhttp://krishna.gs.washington.edu/download/CADD/v1.3/1000G_phase3_inclAnno.tsv.gz), which incorporates data from ENCODE and NIH Roadmap Epigenomics using ChromHMM (https://sites.google.com/site/anshulkundaje/projects/epigenomeroadmap#TOC-Core-Integrative-chromatin-state-maps-127-Epigenomes-)  database (enomes-) .http://mendel.stanford.edu/SidowLab/downloads/gerp/). The GERP++ method was used to calculate site-specific RS scores and discover evolutionarily constrained elements (We measured the evolutionary constraints of each variant using Genome Evolutionary Rate Profiling (GERP)  of DNase evidence for open chromatin. The transcription factor binding site (TFBS) is indicated by the number of different overlapping ChIP transcription factor binding sites. It also defines the boundaries between active and heterochromatic DNA. Transcriptional repressor CTCF is a versatile transcription regulator involved in regulating the 3D structure of chromatin. In addition, splice site analysis indicates whether the tested variants are located in the ACCEPTOR or DONOR sequences.The H3K4Me1 value indicates the maximum ENCODE H3K4 methylation level , where modification of histone proteins is suggestive of an enhancer and, to a lesser extent, other regulatory activities. The H3K4Me3 value indicates the maximum ENCODE H3K4 trimethylation level , where modification of histone proteins is suggestive of a promoter. The DNase-I hypersensitivity sites indicate chromatin regions hypersensitive to cutting by the DNase enzyme. In general, gene regulatory regions tend to be DNase-sensitive, and promoters are particularly DNase-sensitive. DNase-P indicates the EP300 single nucleotide polymorphisms (SNPs) was conducted using publicly available datasets (Blood eQTL Browser: http://genenetwork.nl/bloodeqtlbrowser/).The eQTL analysis for candidate n=127, 37.41±3.8 years old) at an elevation of 4 700 m and Lhasa city  at an elevation of 3 600 m. Written informed consent was obtained from all participants. For physiological parameters, we determined the hemoglobin (Hb) concentration, arterial oxygen saturation (SaO2) level, and blood nitric oxide (NO) concentration, which are key adaptive physiological traits in Tibetans  at rest. Venous blood was collected for Hb measurement and DNA extraction. To reveal the NO level in serum, predominant species NO2− and NO3− were measured using a nitric oxide analyzer .The Hb concentration was measured using a HemoCue Hb 201+ analyzer  and SaOEP300 and likely influenced gene expression. For multiple test correction, we performed 100 000 permutations.We genotyped six candidate variants and conducted association analysis in 226 Tibetans. The variants were rs58268766, rs2076578, rs2076580, rs5758251, rs5758256, and rs2143694. Genotyping was conducted by the SNaPshot method on an ABI 3130 sequencer . Genetic association analysis was conducted using PLINK 1.07 . An addiEP300 genomic region, covering the 88.9 kb gene region as well as two 10 kb flanking regions upstream and downstream of EP300. In total, we obtained EP300 sequencing data of 80 unrelated Tibetans.We resequenced a 108.9 kb EP300 sequence variants among the 80 unrelated Tibetans. After comparing with three lowlander populations, including Han Chinese, Europeans, and Africans, there were 149 shared variants. The remaining 36 variants were all rare mutations in Tibetans ( < 1.0%). To detect selection signals of these variants, we performed neutrality tests, including both allele-frequency-based (FST and Tajima's D) and haplotype-based tests (iHS and XP-EHH). Consistent with previous research (FST > 0.03) between Tibetans and Han Chinese. The highest FST was 0.14 for rs2076580. The derived allele at rs2076580 was predominant in Tibetans (76%), much higher than the frequencies in the lowland reference populations . Consistently, in the haplotype-based XP-EHH test, we found 34 EP300 variants showing high scores (XP-EHH > 0.2) (Supplementary Table S1). These high-XP-EHH variants were likely under positive Darwinian selection, and were located in a LD block spanning about 6 kb from intron-6 to the 3' flanking region , and except for two synonymous variants, most were non-coding. We performed functional prediction based on sequence conservation (GERP), transcription factor binding sites (TFBS), splicing motif, H3K4Me1/H3K4Me3 sites, and DNAase-I hypersensitive sites. There were 14 variants showing conserved sequences across species (GREP++ > 5.0), an implication of functional constraint. In addition, multiple variants were located in the H3K4Me1/ H3K4Me3 sites, suggesting their potential involvement in enhancer or promoter activities (Supplementary Table S1).With the detected signal of selection on http://genenetwork.nl/bloodeqtlbrowser/), and found that three candidate variants showed highly significant association with the expression of EP300 in blood , suggesting that these variants are probably involved in the expression regulation of EP300. However, further experiments are needed to test their suggestive functions.We also performed eQTL analysis using published data . Six candidate variants were selected based on their FST values and XP-EHH scores (FST > 0.1 and XP-EHH > 2.0). As shown in P < 0.05, after multiple test corrections with permutations). The same result was observed when males and females were analyzed separately  motifs in the gene promoter regions (NOS3 and NOS2 can be directly regulated by HIF1α and HIF2α. Therefore, the observed association of EP300 with blood NO level can be explained by the co-transactivating role of EP300 in expression regulation of HIF1α and eventually its downstream genes, including NOS3 and NOS2. Notably, eNOS mainly functions in blood vessels (EP300 works in histone modification (EP300 in high-altitude adaptation involves downstream gene regulation through chromatin remodeling is yet to be tested.Importantly, we observed a significant association of many high XP-EHH variants with NO concentration. It has been proposed previously that high NO levels are an adaptive feature of Tibetans for high altitude living. Prior studies have shown that the NO levels of 88 Tibetans living at 4 300 m elevation were 10 times higher than those of 50 European-Americans living at 203 m elevation . High NO regions . In othe vessels . As EP30fication , whetherUnder hypoxic conditions, in addition to the pathway of stabilizing HIF with reduced PHD2 hydroxylation, the nitroso sulfation of the HIF element is also important , and NO EP300 has been under positive Darwinian selection, with a significant association with blood NO levels in Tibetans. These data suggest that EP300 likely contributes to Tibetan adaptation to high-altitude. However, further studies are needed to reveal the underlying molecular mechanism.In summary, we proved that We are grateful to all the volunteers participated in this study.


Hydrofluorocarbons, currently used as refrigerants in air-conditioning systems, are potent greenhouse gases, and their contribution to climate change is projected to increase. Future use of the hydrofluorocarbons will be phased down and, thus replacement fluids must be found. Here we show that only a few pure fluids possess the combination of chemical, environmental, thermodynamic, and safety properties necessary for a refrigerant and that these fluids are at least slightly flammable. We search for replacements by applying screening criteria to a comprehensive chemical database. For the fluids passing the thermodynamic and environmental screens , we simulate performance in small air-conditioning systems, including optimization of the heat exchangers. We show that the efficiency-versus-capacity trade-off that exists in an ideal analysis disappears when a more realistic system is considered. The maximum efficiency occurs at a relatively high volumetric refrigeration capacity, but there are few fluids in this range. With societies phasing down the use of hydrofluorocarbons (HFCs), alternative environmentally-friendly refrigerants are required. Here the authors screen a large chemical database for replacements, performing simulations to show there are only a few candidate single-component fluids that can realistically replace HFCs. Hydrofluorocarbons (HFCs), which are currently used as refrigerants in air-conditioning (AC) systems, are potent greenhouse gases, with high values of global warming potential (GWP). Although the present contribution of the HFCs to climate change is small, their contribution is projected to rapidly increase under various scenariosA refrigerant is the essential working fluid in a vapour-compression refrigeration cycle; it absorbs heat at a relatively low temperature in the evaporator  and releases it at a higher temperature in the condenser . HFC refrigerants were commercialized in the 1990s as replacements for the ozone-depleting chlorofluorocarbons and hydrochlorofluorocarbons. The HFCs are now the dominant refrigerants in new refrigeration, AC and heat-pump equipment. In particular, HFCs are used in small AC systems known as unitary systems: self-contained systems comprising a positive-displacement compressor, condenser, evaporator, and associated fans and controls. R-410A (a blend of HFCs) is currently the dominant refrigerant in such systems. R-22 (a hydrochlorofluorocarbon) was most commonly used prior to R-410A, and it is still commonly used in developing countries. , defined as the refrigeration effect per unit volume of refrigerant vapour entering the compressor. The COP determines the energy efficiency of an AC system, and Qvol has a large influence on the physical size of the equipment, with larger values of Qvol corresponding to more compact systems. We considered hypothetical fluids—as defined by the liquid–vapour critical temperature (Tcrit), critical pressure (pcrit), heat capacity of the vapour on a molar basis  yielded 138 fluids. The PubChem database does not provide these data for the vast majority of the compounds, so they were estimated using methods based solely on molecular structure; these estimations constituted a major effort of this project1014Tcrit. Although refrigerants with values of GWP as low as possible are obviously desirable, fluids with GWP100<750 are, for example, permitted under EU regulations in AC systems with <3 kg of refrigerantTcrit and GWP100 for each fluid.Further screens for 320 K<The next screens were for chemical stability and toxicity. Compounds with generally unstable functional groups were dropped from further consideration. For example, peroxides (compounds with the –O–O– group) are unstable. Ketenes (compounds with the –C=C=O group) are generally very reactive, and three such compounds were dropped. Allenes have the –C=C=C– group and are characterized as ‘difficult to prepare and very reactive'3)2C=CF2), an extremely toxic compound, than for R-134a (CF3CFH2), a molecule with very low toxicity. ; this is the observation that the =CF2 group has a high reactivity which is often associated with toxic effects. The presence of a =CF2 group does not assure that a molecule is toxic, but we are aware of only one possible counterexample of R-1123, which has an acute toxicity similar to that of the commercialized refrigerant R-1234ze(E)2 group does not, however, imply that a molecule is of low toxicity. Fluids having the –OF group were also dropped. The –OF group is analogous to the –OH group that defines an alcohol. The bond dissociation energy of the O–F bond, however, is less than one-half that of the O–H bond in an alcoholAttempts to automate the screening of toxicity were not successful. We tested the Toxicity Estimation Software Tool of the US EPAThe screening of the candidate molecules considered their simulated performance in equipment with operating conditions representative of ACQvol=6.62 MJ·m−3 and COP=7.41. The volumetric capacity of R-22 is 66% that of R-410A, so this would correspond to dropping fluids with a capacity less than one-half that of R-22.) The stability, toxicity and performance screens yielded a set of 27 low-GWP fluids that were then simulated in greater detail.This screening proceeded in two rounds. The first round of cycle simulations made use of the theoretical CYCLE_D modelet al.The second round of simulations made use of a more advanced ‘optimized' cycle model that provided a more realistic representation of an air conditioner employing typical forced-convection, air-to-refrigerant heat exchangers, which were optimized for a particular refrigerant. In this type of heat exchanger, the refrigerant undergoes a phase change as it flows down the inside of a tube and exchanges heat with air on the outside of the tube. Specifically, the new model accounted for the effect of optimized refrigerant mass flux, which enhances the refrigerant heat transfer coefficient at an acceptable penalty of the pressure drop, as described by Brown Qvol, low COP or are unstable or toxic. We also included in This screening process yielded 27 low-GWP fluids we deem to be the best single-component low-GWP replacements for unitary AC systems, see Qvol of the candidate fluids, based on the optimized model, are presented in Qvol higher than that of R-410A, but this advantage comes with a GWP100 of 677. R-134 and R-E143a have GWP100 values of 1120 and 523, respectively. Three fluids have GWPs within the 80–150 range, and GWPs for the remaining fluids do not exceed 20. Except for R-32, R-1123 and R-1141, the listed fluids have Qvol lower than R-410A and would thus require a larger compressor—by at least 25%—and, for a majority of the candidates, more than twice as large—to provide the same capacity as R-410A. Qvol for carbon dioxide, ethane and R-41 because their Tcrit are low and they may require a different  cycle, depending on operating conditions. We list them because they may be suitable as a component of a blend. In general, fluids with a low Tcrit (corresponding to high Qvol) suffer performance degradation at high ambient temperatures.The COP and Tcrit=344.5 K) and R-32 (Tcrit=351.3 K), in these applications. Consequently, other refrigerants in Tcrit=327.1 K), R-1123 (Tcrit=343.0 K) and tetrafluoromethaneamine (Tcrit=342 K), are probably not viable candidates for systems operating in high-ambient-temperature conditions.Our assumed conditions were an evaporator temperature of 10 °C and condensing temperature of 40 °C; these are representative for the majority of AC systems in North America, Europe and Japan. The conclusions regarding suitable fluids for higher-ambient temperatures may differ, however, as exemplified by the concerns regarding the viability of current refrigerants having relatively low critical temperatures, such as R-410A , R-1270 (propene) and tetrafluoromethaneamine) have slightly higher, rather than lower, values of Qvol when referenced to R-22.Compared with R-410A, the COP of R-22 is slightly higher, and the Qvol values that are at least 60% of that for R-410A; the upper range of optimal Qvol is somewhat extended above 110% for the economizer cycle because we normalized the data with R-410A values for the basic cycle. The LL/SL-HX cycle  extracts a smaller COP penalty on the high Qvol  fluids when the heat exchangers are optimized.  An additional effect is that the low-Qvol fluids tend to be more complex molecules  because the use of a high-pressure fluid, such as R-410A, would result in such a small compressor that mechanical losses would become large.−1) are being considered for use. R-1225ye(Z) is nonflammable but has a capacity of only about one-fourth that of R-410A. R-1225ye(Z) has low acute toxicity2 would require extensive redesign of current equipment types and was not simulated here.Most of the candidate fluids identified are flammable or mildly flammable. The refrigerant classification standards4Qvol values that are about 40% lower than that of R-410A. They are flammable (in addition to possible other hazards), and their COP and Qvol are very similar to propane (R-290). This raises the question, why take on the unknown risks of these fluids when one could use the somewhat more flammable but well-known propane? R-134 has a relatively high GWP100 of 1120. It was investigated in the 1990s but never used commercially; it may be of interest as a blend component.We identified six novel molecules in the screening: tetrafluorodioxole, trifluoromethanethiol, trifluoropropyne, difluoromethanethiol, (E)-1,2-difluoroethene (R-1132(E)), and tetrafluoromethaneamine. Few data could be found on these fluids, and they present unknown risks. None of them are particularly compelling from a performance standpoint. Difluoromethanethiol and (E)-1,2-difluoroethene, for example, have predicted COPs slightly higher than R-410A but Our major conclusion is that the viable candidates for single-component low-GWP alternatives for small AC systems are very limited, especially for refrigerants with volumetric capacities similar to R-410A. Fluids with good COP and low toxicity are available, but all are at least slightly flammable. Nonflammable candidates exist among the fluids with low volumetric capacity, but use of such fluids in small AC systems would require extensive redesign and may result in lower COP. Blends offer additional possibilities, and the refrigeration industry is actively investigating blends of HFCs and HFOs with the intent of reducing or eliminating flammability with the trade-off of increased GWP. Although our study focussed on unitary AC systems , the general conclusions would apply also to room AC units and to refrigeration and heat-pumping systems currently using R-410A or R-22. The list of suitable fluids for systems operating at high ambient conditions would be reduced (as presented in the Results section).Accepting thermodynamic arguments that viable refrigerants are restricted to small molecules, there are a finite number of ways to combine the selected elements into stable molecules. It is our contention that the presented screening process has yielded a list see  of the ‘Refrigerant blends offer a compromise between flammability and GWP: for example, a low-GWP but flammable fluid blended with a nonflammable but high-GWP fluid could result in a nonflammable fluid with a moderate value of GWP (order of 500) or a slightly flammable refrigerant with a low GWP (order of 150). The list presented in Our findings give certainty as to the options available to the AC industry in their transition away from high-GWP fluids. It is also important for policy makers to understand these limits and trade-offs as they consider phase-down schedules.The PubChem databaseet al.et al.100 of compounds based only on their molecular structure; the method combined estimates of the radiative efficiency and atmospheric reactivity with the hydroxyl radical. The trade-off of computational efficiency versus accuracy was a major consideration given the large number of compounds to screen. The method achieved a logarithmic root-mean-square deviation of 3.0 for the GWP100 estimate compared with available literature values, and this accuracy was adequate for screening purposes. Applying a screen of GWP100<200 resulted in 52,565 compounds, that is, the vast majority of these molecules have short atmospheric lifetimes and low GWP. Further screens for toxicity ; (2) COP>5; (3) low toxicity ; and (4) acceptable chemical stability. Several additional fluids were also included in 100=1,120 (ref. Cycle simulations (as described below) were carried out on these 138 fluids. A literature search on the toxicity and chemical stability of the candidates was conducted, except that fluids with a low volumetric capacity in the ideal vapour compression cycle were not considered further. The selection of a fluid for inclusion in the ‘final' list that is,  was base120 ref. ; it is n3-C≡CH) and propa-1,2-diene (CH2=C=CH2) present an interesting situation. These fluids have normal boiling points of −23 and −34 °C, respectively, and moderate values of Qvol in the ideal-cycle simulation (see Propyne (CHtion see . The twoω (a parameter related to the slope of the vapour pressure with respect to temperature) and the heat capacity of the vapour. Although the screening of the PubChem database made use of the critical temperatures estimated by the method of Kazakov et al.Tcrit, pcrit and ω used in the ECS model were estimated with the more recent method of Carande et al.et al.et al.et al.For the cycle simulations carried out on the list of 138 fluids, we employed the detailed EOS models for the thermodynamic properties implemented in the NIST REFPROP databaseω. We implemented four such methods: Ambrose  through the overall heat transfer coefficient, U, heat transfer area, A, and mean effective temperature differences, ΔT, where the heat transfer rates are given by Q=UA·ΔT. The mean effective temperature differences, ΔT, are determined from the temperature profiles of the heat sink and heat source and the refrigerant-side temperature profiles in the evaporator and condenser. The solution scheme divides the heat exchangers into as many as 128 segments and includes sections in the condenser for vapour desuperheating, two-phase condensation and liquid subcooling and sections in the evaporator for two-phase evaporation and vapour superheating. The ‘optimized' model is not a detailed simulation model. Rather it accounts for the effects of refrigerant thermophysical properties on heat transfer coefficients and refrigerant pressure drops in the heat exchangers in relation to those of a reference refrigerant in a reference system , and it assumes heat transfer resistances on the air sides of the heat exchangers to be constant, as presented by Brown et al.2741The ‘optimized' cycle model used to simulate the results presented in The refrigerant flows through multiple tubes in the evaporator and condenser, and the model optimizes the COP by distributing the flow among one or more refrigerant circuits in each heat exchanger. An increase in the number of tubes per refrigerant circuit in effect lowers the refrigerant mass flux per tube leading to a lower refrigerant-side heat transfer coefficient more or less proportionally with mass flux while at the same time lowering the refrigerant-side pressure drop per tube more or less quadratically with mass flux. Conversely, decreasing the number of tubes per refrigerant circuit has the opposite effects on the refrigerant-side heat transfer coefficient and pressure drop. These effects result in an optimum refrigerant-side refrigerant flow path that maximizes COP by striking a balance between the positive influence on COP of higher refrigerant mass flux through increasing heat transfer coefficient and the negative influence on COP of higher refrigerant mass flux through increasing pressure drop.100, the thermodynamic properties and the simulated cycle performance in an AC application . The GWP100 for 17 of the 27 fluids presented in et al.100, Kazakov et al.100 corresponded to a factor of 3.0. Although this is a large uncertainty, it is adequate for screening purposes, especially considering that a GWP100 of the order of 1.0 was estimated for a large fraction of the compounds considered—a value of 0.3 or 3.0 would still put such a fluid in the category of ‘extremely low GWP.'The screening of candidate molecules in this study was based primarily on values of GWPThe uncertainties in the simulated cycle performance arise from two sources. The first source stems from the assumptions and idealizations made in the cycle model. Here all fluids were simulated with the same assumptions, and we were concerned only with relative differences between fluids.Tcrit, pcrit, ω and ideal-gas heat capacity  source of uncertainty in the simulation results stemmed from the thermodynamic properties. For the 22 fluids, we made use of the comprehensive, high-accuracy EOS implemented in the NIST REFPROP database24et al.Tcrit estimated by the method of Carande et al.The sensitivity study described above for R1132(E), R1141 and R1225ye(Z) will apply for all the fluids. Additional fluids were estimated by the method of Carande Qvol are relatively large for individual fluids, the overall trends and conclusions remain valid. The minimum value of Qvol for inclusion in Tcrit for inclusion in the evaluation .Publisher's note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.Supplementary Table and Supplementary References


Altered power of resting-state neurophysiological activity has been associated with autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD), which commonly co-occur. We compared resting-state neurophysiological power in children with ASD, ADHD, co-occurring ASD + ADHD, and typically developing controls. Children with ASD (ASD/ASD + ADHD) showed reduced theta and alpha power compared to children without ASD (controls/ADHD). Children with ADHD (ADHD/ASD + ADHD) displayed decreased delta power compared to children without ADHD (ASD/controls). Children with ASD + ADHD largely presented as an additive co-occurrence with deficits of both disorders, although reduced theta compared to ADHD-only and reduced delta compared to controls suggested some unique markers. Identifying specific neurophysiological profiles in ASD and ADHD may assist in characterising more homogeneous subgroups to inform treatment approaches and aetiological investigations. Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are two of the most common and impairing neurodevelopmental disorders which frequently co-occur and share genetic mechanisms  activity and decreased fast-wave  activity compared to controls. Finally, we predicted that children with ASD + ADHD would show additive ASD- and ADHD-related atypicalities in resting-state power, characterised by increased delta and theta power and reduced alpha power compared to controls, as well as decreased beta power compared to the ASD group but increased beta power compared to the ADHD group. This would suggest that the co-occurring symptoms reflect true overlap between ASD and ADHD at the neurophysiological level.n = 19), ADHD (ADHD group: n = 18), or ASD + ADHD (ASD + ADHD group: n = 29), and typically developing boys (Control group: n = 26). We included only male participants to reduce sample heterogeneity. Group characteristics are presented in Table Participants were boys aged 8–13 years with ASD (ASD group: Participants completed 6 min of eyes-open (EO) resting-state EEG during a 1-h EEG task battery, which also included 6 min of eyes-closed resting state and a series of experimental tasks (data not presented here). During the EO resting-state, participants fixated on a dot on the opposite wall and were encouraged to minimise ocular and other movements.EEG was recorded continuously from 62 Ag/AgCl active (actiCAP) scalp electrodes placed according to the extended 10–20 system using an ActiCHamp (active channel amplifier) DC-coupled Brain Products recording system . The data were referenced online to electrode FCz and sampled at 500 Hz. Electrode impedances were kept below 10 kΩ. Vertical and horizontal eye movements were recorded from electrodes placed above and below the left eye and at the outer canthi. EEG data were processed offline using Brain Vision Analyzer v2.03 . Flat or noisy channels were removed and interpolated using spherical spline interpolation prior to re-referencing to the average reference and filtering with 0.1 Hz high-pass, 30 Hz low-pass, 50 Hz notch Butterworth 24dB/Oct filters. Independent components analysis (ICA) was used to identify and remove ocular artefact components after which the data were segmented into 2-second non-overlapping epochs within the EO condition. Automated artefact-detection was used to exclude any epochs with remaining artefacts, defined as those with amplitudes exceeding ±90 µv or a peak-to-peak amplitude change of 200 µv; this resulted in the exclusion of between 1 and 166 epochs (2–332 s/0.6–92% of the EO data) across participants . Clean epochs were subjected to Fast Fourier Transform (FFT) with a 10% Hanning window taper to obtain absolute spectral power in the delta (0.5–3.5 Hz), theta (4–8 Hz), alpha (8–12 Hz) and beta (12–20 Hz) frequency bands. Following previous research  = 0.68, p = .58, ηp2 = 0.027; ASD mean (SD) = 123.94 (45.88), ADHD mean (SD) = 126.80 (47.57), ASD + ADHD mean (SD) = 140.76 (42.78), Control mean (SD) = 139.95 (45.88)]. The majority of the children included in the final analysis had at least 45 epochs (90 s) of artefact-free data for analysis; one child with ASD + ADHD had only 23 epochs. Statistical analyses were repeated without this child and results are reported wherever they differ from the main analyses.Participants were excluded from analyses if they had <40 s of artefact-free data (20 epochs) according to the artefact-rejection criteria described above, or had power values (prior to log transform) 3.5SD outside of their group mean. Three control boys, one boy with ASD, three boys with ADHD, and four boys with ASD + ADHD were excluded due to having insufficient artefact-free epochs for analysis (<15 epochs). The EEG data from these children was characterised by excessive muscular artefact and slow waves. A further one control boy, two boys with ASD, and four boys with ASD + ADHD were excluded for having outlying power values in multiple frequency bands. The analysis of resting-state power was therefore conducted on a final sample of 22 Controls, 16 ASD, 15 ADHD, and 21 ASD + ADHD. The number of epochs included in analysis did not differ between groups  and a significant group*cluster interaction  on absolute delta power. The main effect of cluster reflected significant differences in delta power between all pairs of electrode clusters , with power greatest at occipital and frontal scalp. The group*cluster interaction reflected significantly lower delta power in the ADHD group than the ASD group at the frontal cluster , significantly lower power in both ADHD and ASD + ADHD groups than the ASD group at the central cluster , and significantly lower power in the ASD + ADHD group than the Control group at the parietal cluster   = 6.40, p = .01, ηp2 = 0.086], reflecting significantly lower delta power in boys with ADHD than those without ADHD. This effect was qualified by a significant ADHD*cluster interaction , which showed that the reduction in delta power in boys with ADHD was significant at frontal , central , and parietal  clusters. There was also a significant ASD*cluster interaction , which revealed a trend for increased delta power in boys with ASD compared to boys without ASD at the frontal cluster . The interaction between the ASD and ADHD factors was non-significant  supporting additive effects of ASD and ADHD. Age  but not IQ  was a significant covariate in these models.There was a significant main effect of electrode cluster , reflecting significant differences between all pairs of electrodes  with power largest at frontal and occipital scalp, and a marginal main effect of group , reflecting a trend for greater theta power in the ADHD than ASD + ADHD group   = 3.01, p = .004, ηp2 = 0.117], which showed that the ADHD group had significantly greater theta power than the ASD + ADHD group at parietal scalp . Combining the groups by ASD/ADHD diagnosis, there was a significant main effect of ASD , which reflected significantly lower theta power in boys with ASD than boys without ASD. There was also a significant ADHD*cluster interaction , but follow-up Bonferroni-corrected pairwise group contrasts at each electrode cluster separately revealed no significant differences between boys with ADHD and those without ADHD . The ASD*ADHD interaction was non-significant , supporting additive effects. Age was a significant covariate in these models , while IQ was non-significant .There was a significant main effect of cluster on absolute theta power  on absolute beta power, reflecting greater power at the central cluster than all other clusters , as well as a significant group*cluster interaction . However, further investigation of this interaction revealed no significant differences between the four groups at any of the clusters . There were no significant main effects of ASD or ADHD and no interaction between these factors when combined by diagnosis . Age and IQ were non-significant covariates .There was a significant main effect of cluster , theta power at frontal , central , and parietal  clusters, and with alpha power at frontal , central , parietal , and occipital  clusters, indicating children with higher levels of ASD symptoms or traits had lower delta, theta, and alpha power. There were no significant associations between hyperactive/impulsive or inattentive symptoms of ADHD and power at any frequency or cluster .SCQ scores were significantly negatively correlated with delta power at the parietal cluster [This study examined neurophysiological activity during the resting-state in children with ASD, ADHD, and co-occurring ASD + ADHD compared to typically developing controls. The findings appear to dissociate ASD and ADHD on the basis of different neurophysiological power profiles. Specifically in relation to our hypotheses, (1) children with ASD showed reduced theta and alpha power compared to children without ASD; (2) children with ADHD showed decreased delta power compared to children without ADHD; and (3), children with ASD + ADHD displayed a largely additive profile with the unique deficits of both ASD and ADHD, although specific differences compared to “pure” cases of ASD and ADHD were also observed.Children with ASD (ASD/ASD + ADHD) demonstrated a unique EEG profile of reduced power in the theta and alpha frequencies compared to children without ASD. This pattern partially contrasts with previous suggestions of a U-shaped profile in ASD with increased power at low  and high (beta) frequencies and reduced alpha power  showed reduced delta power in fronto-central and parietal regions compared to children without ADHD. Previous work has found either no differences in delta between children and adults with ADHD and controls (Buyck and Wiersema In contrast to our hypotheses and many previous studies (Barry et al. Our findings converge to suggest a dissociation between ASD and ADHD on the basis of their cortical EEG profiles, whereby children with ASD display a high delta, low theta and low alpha pattern and children with ADHD display a low delta pattern. Importantly, children with ASD + ADHD largely present as an additive co-occurrence of both ASD and ADHD, with low delta, low theta and low alpha patterns, rather than presenting as a distinct entity with unique patterns of EEG power. The finding that the ASD + ADHD group presents with the unique deficits of both disorders suggests it cannot be assumed that the correlates and aetiology of ASD are the same regardless of the presence of absence or ADHD, and vice versa (Caron and Rutter Several limitations should be taken into consideration. The small sample size limits firm conclusions and along with heterogeneity in EEG profiles may have contributed to null findings. For example, lack of group differences on beta power may reflect the presence of distinct EEG subtypes that have been described in children with ADHD, that differ on deficiency versus excess beta power (Clarke et al. In conclusion, this study extends previous studies of EEG power in ASD and ADHD by identifying distinct profiles, while demonstrating that children with comorbid ASD + ADHD largely demonstrate the unique deficits of both disorders. Examination of EEG power at rest is therefore useful in elucidating the basis of these overlapping neurodevelopmental disorders and the potential biological pathways that underlie comorbidity. Such findings are likely to show clinical value by aiding in evaluating the validity of non-invasive EEG in the diagnosis and targeted treatment of more homogenous subgroups of neurodevelopmental disorders, and informing aetiological investigations.


Background: Neurofeedback training (NFT) to decrease the theta/beta ratio (TBR) has been used for treating hyperactivity and impulsivity in attention deficit hyperactivity disorder (ADHD); however, often with low efficiency. Individual variance in EEG profile can confound NFT, because it may lead to influencing non-relevant activity, if ignored. More importantly, it may lead to influencing ADHD-related activities adversely, which may even result in worsening ADHD symptoms. Electromyogenic (EMG) signal resulted from forehead muscles can also explain the low efficiency of the NFT in ADHD from both practical and psychological point-of-view. The first aim of this study was to determine EEG and EMG biomarkers most related to the main ADHD characteristics, such as impulsivity and hyperactivity. The second aim was to confirm our hypothesis that the efficiency of the TBR NFT can be increased by individual adjustment of the frequency bands and simultaneous training on forehead muscle tension.Methods: We recruited 94 children diagnosed with ADHD (ADHD) and 23 healthy controls (HC). All participants were male and aged between six and nine. Impulsivity and attention were assessed with Go/no-Go task and delayed gratification task, respectively; and 19-channel EEG and forehead EMG were recorded. Then, the ADHD group was randomly subdivided into (1) standard, (2) individualized, (3) individualized+EMG, and (4) sham NFT (control) groups. The groups were compared based on TBR and EEG alpha activity, as well as hyperactivity and impulsivity three times: pre-NFT, post-NFT and 6 months after the NFT (follow-up).Results: ADHD children were characterized with decreased individual alpha peak frequency, alpha bandwidth and alpha amplitude suppression magnitude, as well as with increased alpha1/alpha2 (a1/a2) ratio and scalp muscle tension when c (η2 ≥ 0.212). All contingent TBR NFT groups exhibited significant NFT-related decrease in TBR not evident in the control group. Moreover, we detected a higher overall alpha activity in the individualized but not in the standard NFT group. Mixed MANOVA considering between-subject factor GROUP and within-subject factor TIME showed that the individualized+EMG group exhibited the highest level of clinical improvement, which was associated with increase in the individual alpha activity at the 6 months follow-up when comparing with the other approaches .Conclusions: This study identified various (adjusted) alpha activity metrics as biomarkers with close relationship with ADHD symptoms, and demonstrated that TBR NFT individually adjusted for variances in alpha activity is more successful and clinically more efficient than standard, non-individualized NFT. Moreover, these training effects of the individualized TBR NFT lasted longer when combined with EMG. It has been already well-described that the main characteristics of attention deficit hyperactivity disorder (AHDH), such as inattention, impulsivity and hyperactivity are associated with a phenomenon so called “slow electroencephalogram (EEG)”  signal resulted from forehead muscles can also explain the low efficiency of the NFT in ADHD. Several studies has shown that EEG in frequency ranges below 10 Hz and above 13 Hz are the most contaminated by EMG signal, and therefore it is almost impossible to distinguish power in theta and beta ranges from slow EMG power  ratio, as well as that of the forehead EMG in ADHD symptomatology. We investigate whether they could serve as neurophysiological biomarkers of ADHD. Another focus of interest is whether neurofeedback training simultaneously aiming both to decrease TBR in individually determined frequency ranges and to reduce forehead muscle tension could be more efficient than conventional TBR NFT. We also hypothesize that the proposed optimized EEG/EMG NFT protocol would lead to higher alpha activity indices in addition to the steeper TBR decreases and that these effects last longer. We also hypothesize that these changes in the neurophysiology will be accompanied by corresponding behavioral improvements. Our study will demonstrate the importance of individual alpha indices and the forehead muscle tension not only in the diagnosis of ADHD but also in the optimization of the neurofeedback training protocol in treatment of ADHD.We recruited 94 children diagnosed with ADHD (ADHD) and 23 healthy controls (HC). All participants were male and aged between six and nine. Mean and standard deviation of age were 7.0 ± 0.20 and 7.5 ± 0.28 in the ADHD and the healthy groups, respectively. All participants' parents gave their informed consent in accordance with the Declaration of Helsinki prior to the study. The Medical Ethics Committee of the Siberian branch of the Medical Science Academy approved this study. All patients fulfilled DSM-IV criteria for ADHD , (b) primarily hyperactive-impulsive type (n = 30), and (c) combined type (n = 35). ADHD group overall differed significantly from HC in inattention  and hyperactivity/impulsivity .ADHD group was further categorized into the three qualifying types: (a) primarily inattentive type . Then ADHD participants were randomly assigned to four groups for NFT to decrease TBR:n = 17), where standard frequency bands of 4–8 Hz (theta) and 12.5–20 Hz (beta) were used as targets , where theta and beta target frequency bands were individually adjusted , where individually adjusted bands and integrated power of the forehead muscle EMG were used as simultaneous targets;individual NFT group with simultaneous EMG to decrease forehead muscle tension , when participants received random audio-visual feedbacks.sham NFT group  of the treatment is still on debate. A typical course of NFT involves 30–40 sessions, which is very time consuming and expensive; particularly when considering that NFT is rarely covered by health insurance. Thus, there is a constant interest in developing a NFT protocol clinically beneficial in shorter time. Hillard et al.  suggestsParticipants were assessed pre-, post-, and 6-month after the NFT. Assessment consisted of psychometrics, behavioral rating scales completed by parents and teachers, as well as 19-channel EEG and forehead EMG recordings . The letters were presented for 1,000 ms preceded by a 500-ms fixation point in the center of the screen. Participants were also required to inhibit responses to a Go stimulus, when it was accompanied by no-Go stimulus with a delayed onset. The no-Go stimulus was a green circle with a diameter of 3.4° presented 3.2° above the Go stimulus for 150-ms. Reaction times and number of omissions (missed stimuli) in the Go trials were measured.Delayed gratification task: A cake was presented to the participant, who was told to choose between two options: either eating the cake immediately  or waiting for another cake, so that (s)he could eat both. The experiment measured how long the participant resisted the immediate reward.The clinical efficiency of NFT was measured as percent change in the reaction time and the number of missed stimuli in the Go-/no-Go task, as well as in the duration of delayed gratification at the post-NFT and the follow up sessions in comparison with the pre-NFT session.We compared resting state EEG recordings of the two groups in 1 min eyes closed (EC) and 1 min eyes open (EO) condition at the pre-, post-NFT and the follow up sessions. Participants sat in a comfortable chair with a backrest and were instructed not to move their eyes during the recordings. EEG data was acquired using a Neuron-Spectrum-4 system  at a sampling rate of 1,000 Hz and with a bandpass filter between 0.1 and 50 Hz. The EEG electrodes were placed in accordance with the international 10–20 system: 18 electrodes were positioned in four regions: left fronto-central , right fronto-central , left posterior-occipital , and right posterior-occipital , and signal was averaged within each area. Two reference electrodes were fixed at M1 and M2. The ground electrode was placed at Fp1 site. Impedance was kept below 5 kΩ. Data was anti-aliasing/low-pass filtered at 30 Hz.2 were included in the analysis. Analysis of EEG characteristics was carried out according to our previously published approach . Alpha1 to alpha2 ratio (a1/a2) was also calculated.The EEG data were analyzed using WinEEG software . Eye-blink artifacts were removed using Independent Component Analysis, then the recording was divided into 4.096-s-long epochs using a Hanning window (epochs were overlapped by 50%). Only records showing an amplitude above 10 μVEMG and EEG data were simultaneously recorded using Bosalb system,  with the sampling rate of 720 Hz. Feedback signal was recorded from Pz scalp electrode with a bandpass filter between 3 and 30 Hz. Monopolar reference electrode was located on the right ear, and the ground electrode was located at Fp1. Electrode impedance was kept below 5 kOhm. EMG was recorded using two Ag/AgCl surface bipolar electrodes with an effective diameter of 1.6 cm placed about 3–5 cm apart on the forehead. The EMG signal was amplified and filtered with 5–350 Hz bandpass filter.Location of Pz was selected based on the following considerations: (i) alpha activity in the parieto-occipital area is generally proposed as a modulator of the attentional states .Average power of the raw EMG was calculated over 100 ms according to the usual approach . For the iNFT and the iNFT_EMG groups, threshold was based on mean power of individually adjusted frequency ranges (see section Offline EEG). For the iNFT_EMG group, the mean power of integrated forehead EMG was also taken into account, so that feedback signal (flower growth) appeared only when both TBR and the EMG signal lowered below the thresholds, respectively.d ≤ 0.033, p ≥ 0.2).Psychometrics, as well as electrophysiological  data were tested for normality by the Kolmogorov-Smirnov's test and showed normal distribution , CAUDALITY , HEMISPHERE (2 levels: left and right), and CONDITION (2 levels: EC and EO). The second 3-way ANOVA with factors GROUP , CAUDALITY  and HEMISPHERE (2 levels: left and right) was conducted to compare overall ADHD and HC groups. ANOVAs were further extended with Pearson correlation analyses were also performed to analyze the relationship between the psychological measures and the electrophysiology. In order to identify the most powerful electrophysiological predictors of the behavior, a multiple linear regression analysis with forward stepwise selection was conducted on the data of all the 94 ADHD participants using the alpha EEG, TBR, and EMG indices as independent variables, and psychological measures  as dependent variables.Planned pairwise comparisons of the different NFT groups  were conducted for psychometrics, behavioral measures (SNAP-VI), EMG, and feedback signals. Mixed 2-way ANOVAs were performed to evaluate the effect of within-subject factor time  and between-subject factor NFT_GROUP  on all variables of interest.T-test showed no significant difference between ADHD subtype groups in psychometrics  and EMG characteristics . All subtypes of ADHD exhibited significantly increased reaction time  and number of missed stimuli  in Go/no-go task, decreased duration  in Delayed gratification task and increased forehead muscle tension  when compared to healthy peers  and HEMISPHERE [F = 0.1, p = 0.99, η2 < 0.001) on alpha indices and TBR. All subtypes of ADHD showed a decreased alpha power in EO condition . Factor CAUDALITY showed a significant main effect on alpha1 and alpha2 power, ASM, alpha1 and alpha2 bandwidth, as well as on a1/a2 ratio and TBR .The SUBTYPE × CAUDALITY × HEMISPHERE × CONDITION ANOVA showed no significant main effects of SUBTYPE . HEMISPHERE showed no significant main effect. Table post-hoc comparisons of neurophysiological characteristics between the ADHD subgroups and the HC group in a layout similar to Table The GROUP × CAUDALITY × HEMISPHERE ANOVA showed significant main effect of GROUP on alpha1 and alpha2 power, ASM, alpha1 and alpha2 bandwidth, as well as on a1/a2 ratio and TBR , ASM , alpha bandwidth , and positively with a1/a2 ratio , and TBR . Duration of the Delayed gratification task correlated positively with individual alpha peak frequency , ASM , alpha bandwidth , and negatively with a1/a2 ratio  and TBR . Muscle tension measured with EMG also correlated positively with reaction time  and missed stimuli number  in Go/no-go task, and negatively with the duration in Delayed gratification task . According to the multiple linear regression analysis, where pre-training psychological measures of ADHD were included as dependent variables and all EEG and EMG variables were included as predictors, individual alpha peak frequency, individual alpha2 bandwidth, a1/a2 ratio predicted all three psychological measures of ADHD significantly  .EEG and EMG characteristics are based on the offline EEG and EMG data. At the pre-training session, psychometric, EEG and EMG characteristics showed no difference between the NFT groups  and significant TIME × NFT_GROUP interaction on all studied variables  . All these effects remained until the follow-up session 6 months after the NFT in the iNFT_EMG group only . iNFT group showed improvement only in the number of missed stimuli , while neurofeedback training effect severely diminished in other groups by the time of the follow-up session  and TIME  on all variables . NFT efficiency was the highest in the iNFT_EMG group when considering inattention  and impulsivity scores .Mixed ANOVA on behavior assessment with Parent and Teacher Rating Scale interview (SNAP-VI) showed significant main effect of NFT_GROUP  and significant TIME × NFT_GROUP interaction on alpha activity indices and TBR  . All these effects were present at the follow-up session only for the iNFT_EMG group .Mixed ANOVA on EEG indices also revealed significant main effect of TIME  Figure . Post-hoF = 4.09, p < 0.05, η2 = 0.026) and TIME × NFT_GROUP interaction  , and this effect were also present at the follow-up session  (Figure Mixed ANOVA on muscle tension as measured with EMG showed significant main effect of TIME (Individual variances of the EEG profile may confound the neurofeedback training, if ignored. Previous electroencephalographic studies attribute persistent increase in slow wave activity during resting state mostly to increase in theta power in ADHD (Chabot and Serfontein, Our study replicated most of the previous findings regarding the electrophysiological profile of ADHD. We have found decreased alpha and beta powers in agreement with the literature (Bresnahan and Barry, Hyperactivity is also characterized by redundant motoric elements; i.e., patient perform more movements than necessary for a given motor task. This contextual redundancy reflects the inefficiency of inhibitory processes in the sensorimotor coordination (Sterrnan and Friar, Sensorimotor integration is a key for optimal learning, and increase in alpha-2 activity with a simultaneous decrease in forehead EMG is proved to be the most reliable markers of the efficient learning (Sammler et al., By means of group comparison followed by regression analysis, we identified individualized alpha peak frequency, alpha1/alpha2 ratio and forehead muscle tension as the most powerful predictors of ADHD symptoms.We confirmed the lack of efficiency of TBR NFT when using standard bands, as well as its efficiency when EEG bands has been individually adjusted. We further demonstrated that combining NFT with muscle tension control training could lead to a longer lasting training effect. These research findings supports our claim that efficiency of NFT can be improved by considering individual characteristics of the EEG and the muscle tension.OB had substantial contributions to the conception of the work, analysis, interpretation of data for the work and revising it critically for important intellectual content and final approval of the version to be published. She provided of agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. TA had substantial contributions to the analysis, interpretation of data for the work and revising it critically for important intellectual content and final approval of the version to be published. ES had a contributions to the design, acquisition, analysis and interpretation of data for the work. She was drafting the work and revising it critically for important intellectual content.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.