Blastomyces, Coccidioides and Histoplasma). These introns are the most biochemically reactive group II introns ever reported, and they self-splice rapidly under near-physiological conditions without protein cofactors. Moreover, we demonstrated the small molecule targetability of these introns by showing that they can be inhibited by the FDA-approved drug mitoxantrone in vitro. Taken together, our results highlight the utility of structure-based informatic searches for identifying riboregulatory elements in pathogens, revealing a striking diversity of reactive self-splicing introns with great promise as antifungal drug targets.Fungal pathogens represent an expanding global health threat for which treatment options are limited. Self-splicing group II introns have emerged as promising drug targets, but their development has been limited by a lack of information on their distribution and architecture in pathogenic fungi. To meet this challenge, we developed a bioinformatic workflow for scanning sequence data to identify unique RNA structural signatures within group II introns. Using this approach, we discovered a set of ubiquitous introns within thermally dimorphic fungi (genera of  Coccidioides) upon temperature change. It is estimated that three thermally dimorphic fungi endemic in North America  cause >650 000 new infections annually, 50 000 of which are life-threatening  gene leads to potent and selective growth inhibition of this fungus  . These ms fungus .However, it has been difficult to extrapolate and generalize this pharmacological approach because we know little about the location, structures and subtypes of group II introns in therapeutically important fungi. The identification of novel group II introns within pathogen genomes has been hampered by the fact that group II introns do not display extensive sequence conservation. For this reason, conventional group II intron search strategies have focused on identification of reverse-transcriptase (RT) proteins known as ‘maturases’ that are encoded within certain group II intron subtypes . While tHere, we describe an RNA structure-guided approach for discovering novel group II introns in fungal organisms and for defining their functional architecture. This approach has enabled us to discover structurally well-defined, biochemically reactive group II introns in various human pathogenic fungi. Furthermore, we show that these reactive introns are readily inhibited by a small molecule that targets RNA tertiary structure. Our results reveal a diverse and previously invisible intron landscape within human pathogenic fungi, thereby facilitating the future development of group II introns as novel antifungal drug targets for the treatment of severe systemic fungal infections.https://megasun.bch.umontreal.ca/cgi-bin/RNAweasel/RNAweaselInterface.pl) , and the annotations were further subject to manual inspection to validate intron boundaries and flanking gene identity.Reference mitochondrial genomes of human pathogenic fungi were retrieved from NCBI GenBank database  . For mitThe secondary structures were predicted using the mfold webserver  with conB.d.LSU.I1, C.i.LSU.I3 and C.i.SSU.I1 introns, the original intron domain 4 sequence (containing intronic ORF sequence) was reduced to a simple stem-loop capped with UUCG tetraloop  and cloned into the pUCminusMCS vector. For H.c.LSU.I1 intron, pLTS103 for C.i.LSU.I3 intron, pLTS104 for C.i.SSU.I1 intron and pLTS105 for B.d.LSU.I1 intron) were linearized using BamHI (New England Biolabs) to generate the DNA template for in vitro transcription.The plasmids containing the sequences of the intron self-splicing constructs  and 1 mM of UTP along with 50 μCi of [α-32P]-UTP (PerkinElmer) were added for the transcription. The reaction was incubated at 37°C for 1.5 h, followed by purification on a 5% denaturing polyacrylamide gel. The band corresponding to precursor RNA was cut and eluted overnight in a gel elution buffer . The RNA transcripts were ethanol precipitated and resuspended in a RNA storage buffer (6 mM MES-NaOH pH 6.0). The RNA stock solution was aliquoted and stored frozen.Radiolabeled precursor RNA transcripts were prepared using 5 μg of linearized plasmid and T7 RNA polymerase (expressed and purified in-house) in a transcription buffer containing 40 mM Tris-HCl pH 8.0, 10 mM NaCl, 15 mM MgCl4-HEPES pH 7.5 at 90°C for 1 min, followed by incubation at 37°C for 10 min. Monovalent salt stock solution was then added. For reaction with PEG-8000, 50% (w/v) stock solution was also added to the final concentration of 10% (w/v). After incubation at 37°C for 10 min, the splicing reaction was initiated by adding 2 μl of 10× MgCl2 stock solution  to a final volume of 20 μl and incubated at 37°C. To monitor reaction time courses, 1 μl was removed from the reaction mixture at specific time points and quenched by mixing with 2× formamide loading buffer (72% (v/v) formamide, 10% sucrose, 0.2% bromophenol blue dye, 0.2% xylene cyanol dye and 50 mM EDTA) and placing on ice. The timepoint samples were then loaded on to a 5% denaturing polyacrylamide gel to resolve individual bands.For the self-splicing assay, body-labeled precursor RNA  was incubated in 40 mM NH4-HEPES pH 7.5 and 2 mM MgCl2 was used for the assay involving the C.i.LSU.I3 and C.i.SSU.I1 introns and the buffer containing 40 mM NH4-HEPES pH 7.5, 150 mM NH4Cl and 10 mM MgCl2 was used for the H.c.LSU.I1 intron. Total reaction volume was 20 μl and the reaction was incubated 37°C. Time points were taken and analysis was done as aforementioned.For the small molecule inhibition assay, body-labeled intron precursor RNA  was incubated with 2 μl of 10× small molecule stock solution ). The reaction buffer containing 40 mM NHGels containing the separated reaction products were dried and exposed to phosphor screens overnight. The screens were scanned using Typhoon FLA9500 phosphorimager  or Typhoon RGB Biomolecular imager (Cytiva). Individual bands were quantified using ImageQuant 8.2 software . The band intensity was corrected for the uridine content of corresponding species and internally calibrated by calculating the fraction of each species in the reaction.fprecursor is the fraction of precursor, factive is the fraction of actively converting precursor, kobs is the observed rate and finactive is the fraction of non-converting precursor.The precursor depletion time course data were analyzed and plotted using Kaleidagraph 4.5.4 software (Synergy Software). Reactions with monophasic kinetic behavior were fitted into Equation .(1)\docufprecursor is the fraction of precursor, ffast is the fraction of fast converting precursor, kfast is the observed rate of fast converting precursor, fslow is the fraction of slowly converting precursor and kslow is the observed rate of slowly converting precursorReactions with biphasic kinetics were fitted into Equation .(2)\docuAll reaction time courses were performed in triplicates and error bars in the kinetic plots were reported as standard errors of the mean (S.E.M.).Ki value for small molecule inhibition, the observed rate constant (kobs) was obtained from the precursor depletion time course, plotted against small molecule concentration and fitted to the noncompetitive inhibition model  and dematiaceous fungi   . The intronic ORF location was also found to be variable, as it was located in D4 for the first mtSSU  intron in C. immitis (C.i.SSU.I1) and in D3 for the second mtSSU intron (C.i.SSU.I2).Having established the intron mining workflow, we then employed it to probe the presence of novel group II introns within the reference mitochondrial genomes of important human pathogenic fungi . In addientified ,15, we ua) Table . Howevera) Table  and therrasitica . Thereforasitica . The GC equence) ,27. MoreH. capsulatum. In the African strain , the intron is ORF-less while in the North American strain , the intron contains the ORF encoding for LHE . By contrast, the SSU introns have two insertion sites  and represent a unique lineage lacking the IBS2–EBS2 interaction, as previously noticed in other fungi  and the two introns from C. immitis represent the LSU and SSU intron lineage respectively. Hence, we selected them for downstream in vitro biochemical characterization.Four introns, namely in vitro. Self-splicing precursor molecules were designed and synthesized from DNA templates using T7 RNA polymerase. After purification and isolation by electrophoresis, these precursor molecules were subject to the pilot self-splicing assay to evaluate the magnesium ion dependence of self-splicing  for further investigation. The B.d.LSU.I2 intron was not subject to additional biochemical characterization as it has high degree of sequence similarity and demonstrates nearly identical biochemical behavior to the H.c.LSU.I1 intron, which is line with the close phylogenetic distance between H. capsulatum and B. dermatitidis  and 10% PEG-8000  at 37°C. The magnesium ion concentration was titrated from 0 to 5 mM . As a comparison, the observed rate constant of DEAD-box helicase Mss116-promoted ai5γ (LE) intron splicing is 0.052 ± 0.0059 min–1   , which iin vitro biochemical reactions are typically performed in a highly diluted solution environment devoid of those factors. To recapitulate the in vivo reaction conditions, crowding agents such as PEG (polyethylene glycerol) have been employed . The precursor depletion time courses . PEGs with shorter length, such as PEG-2000 and PEG-4000, can also promote the efficiency of self-splicing (H.c.LSU.I1 intron precursor RNA with and without PEG-8000 (C.i.LSU.I3 and C.i.SSU.I1 introns achieves 2.00 ± 0.22 min–1 and 2.94 ± 0.18 min–1 (fast species rate), respectively, in the presence of PEG-8000. To the best of our knowledge, these are the fastest rate constants ever observed for a group II intron self-splicing reaction, and it underscores the importance of stable folding and molecular crowding in promoting catalytic efficiency of group II introns.We then examined the effect of crowding agent PEG-8000 on the self-splicing kinetics. Unlike a cellular environment containing osmolytes and macromolecules that affect RNA folding , many inemployed ,35. One ribozyme , so we ss Figure –C revealsplicing  but to aPEG-8000 . Little 4-HEPES pH 7.5 buffer with no additional ammonium salt), self-splicing of C.i.LSU.I3 and C.i.SSU.I1 introns occurs even under conditions of sub-millimolar magnesium ion  were determined to be 0.64 ± 0.08 μM, 0.18 ± 0.03 μM and 0.15 ± 0.01 μM for the H.c.LSU.I1, C.i.LSU.I3 and C.i.SSU.I1 introns, respectively , as it might serve as a selection pressure against intron degeneration or loss. It is known that group II introns can act as temperature sensors for post-transcriptional response to temperature cues (In addition to a possible role in host adaption, it is interesting to postulate the potential involvement of group II intron splicing in the mitochondrial regulatory network of thermally dimorphic fungi that are endemic in North America (ure cues ,47. Thesin vitro and in murine infection models (From a therapeutic perspective, targeting fungal mitochondrial function has become a promising new paradigm in the development of antifungal drugs. A clinical stage mitochondrial functional inhibitor, T-2307, displays potent inhibitory activity against a wide array of pathogenic fungi both n models ,49. In pn models . Here weCryptococcus contains an intein within its central spliceosomal protein Prp8 and small molecules inhibiting specific intein splicing might lead to potent anti-Cryptococcus activity (Beyond autocatalytic introns, the targeting of other selfish genetic elements also emerges as a new concept in the continuous fight against microbial human pathogens. For example, the fungal pathogen activity ,52. TakeAll data are available in the main text or the supplementary materials. Additional data related to this paper may be requested from the corresponding author.gkab1077_Supplemental_FilesClick here for additional data file.


Tearful/sad and Talked spontaneously, and a significant increase in the items Enjoying self, active or alert, and Relaxed, content or sleeping appropriately. Interact scores during the sessions reflected a significant decrease in the speech-related items. Both physiological parameters changed positively from before to after sessions. Our results suggest that BLT provides immediate positive effects on mood, stimulation level, and physiological parameters, as well as a trend toward decreased speech. More robust research is needed to further explore the immediate impact of BLT. This study is registered with Clinicaltrials.gov (NCT04949984).Bright light therapy (BLT) has demonstrated positive short- and long-term effects in people with cognitive impairment or dementia; however, the immediate impact of BLT sessions has been scarcely investigated. In this study, we aimed to explore the immediate effects of BLT on behavior, mood, and physiological parameters (oxygen saturation/heart rate) in a sample of institutionalized older adults with moderate to very severe dementia, with a median age of 85.0 , being higher in men  than in women . The BLT protocol consisted of 30-min morning sessions of 10,000 lux, Monday through Friday, for 4 weeks. The physiological parameters were recorded immediately before and after each session by pulse oximetry. Mood and behavior were assessed before, after, and during the sessions using the Interact scale. Post-session Interact scores showed a significant decrease in the items  Dementia is one of the main causes of disability and dependence among older adults worldwide, constituting a public health priority due to its significant human and financial costs to society . OxidatiTreatment development for BPSD includes both pharmacological and nonpharmacological therapies. In clinical settings, pharmacological agents are frequently used in the management of these symptoms but show modest efficacy and significant serious side-effects ,14, inclIn this study, we focus on bright light therapy (BLT). This therapy consists of the controlled application of certain levels of light that can be administered in different ways, including outdoor sunlight, light boxes, light visors worn on the head, ceiling lights, or dawn-dusk simulation . BLT is This study was designed as a randomized controlled trial. Participants were stratified according to their cognitive status and were subsequently randomly assigned to the experimental group (BLT) or control group. In the analysis and exploitation of results, we only considered the response of the BLT group with regard to the stated objective since the control group did not undergo the intervention needed to complete Interact assessment during the study.n = 64, with a mean age of 88.4 ± 8.0 years and a median age of 89.0 ); 29.7% were men, with a mean age of 88.5 ± 9.4 years and a median age of 91.0 , and 70.3% were women, with a mean age of 88.4 ± 7.5 years and a median age of 88.0 . To delimit the sample, before the recruitment process, inclusion and exclusion criteria were established according to the existing literature. As inclusion criteria, participants were required to satisfy the conditions of being 65 years or older, diagnosed with dementia, scoring ≥4 points on the global deterioration scale (GDS) [Participants were recruited from among the residents of a gerontological complex specializing in dementia (78.7% with cognitive impairment) and located in A Coruña, Spain. The gerontological complex has 70 older people in a day care-setting and 64 institutionalized older people in a nursing home. We selected all institutionalized participants (le (GDS) , and havle (GDS) , individle (GDS) .The research protocol (code 2017/408) received favorable authorization from the Galician Research Ethics Committee of Xunta de Galicia, Spain, and was developed in accordance with the Declaration of Helsinki. The participants and their legal guardians were informed about the study and signed the corresponding informed consent. All the information transmitted was adapted to the level of comprehension of the participants to facilitate their understanding and comfort throughout the study.The study was retrospectively registered with ClinicalTrials.gov (NCT04949984) on 2 July 2021. The study protocol was based on the implementation guidelines that we described in a recent review . The BLTIn every session, the researchers supervised the participants to ensure full compliance with the treatment and evaluated the physiological parameters, mood, and behavior of the participants. Once in the room, the investigators measured the heart rate (beats per minute) and blood oxygen saturation (SpO2) of each participant using a mobile finger pulse oximeter before and after the session.Mood and behavior were assessed during the sessions and in the 10 min periods immediately before and after each session using the Interact scale  and its p < 0.05. The normal distribution of the variables was tested using the Shapiro–Wilk test. For subsequent analyses, we applied parametric or nonparametric tests depending on whether the assumption of normality was met or not for each measured variable. The Wilcoxon signed-rank test or paired t-test were employed to measure significant changes between the Interact short scores before and after the intervention sessions for each of the assessed mood and behavior items. Likewise, these same tests were used to analyze the evolution of the Interact during scores by comparing the average scores of the first week with those of the fourth week. In addition, the evolution of mood and behavior scores throughout the four weeks of treatment was analyzed with the Friedman test for related samples. The paired t-test was also used to determine the existence of any differences between before and after the sessions in the physiological parameters investigated. In the variables in which statistically significant differences were found, Cohen’s d or r values were used to report the effect size (ES) of these changes. The interpretation of the importance of the ES was made according to the benchmarks defined by Cohen [All data were analyzed using the SPSS statistical software package (version 26.0)  and statistical significance was set at by Cohen  as folloAfter applying inclusion and exclusion criteria, the total sample was reduced from 64 to 39 institutionalized older people (20 participants assigned to the control group and 19 to the BLT group). Tearful/sad item (p = 0.044) with a medium effect size (r = −0.32). The results of the paired t-test showed significant changes in the score of the Talked spontaneously item (p = 0.035) with a medium effect size (d = 0.52). Moreover, two items of the Stimulation level construct showed a significant increase in scores: Enjoying self, active or alert (p = 0.034) and Relaxed, content or sleeping appropriately (p = 0.001), with medium (d = −0.52) and large (d = −0.94) effect sizes, respectively.Significant effects were detected between before and after the intervention sessions in 4 of the 12 items evaluated in the Interact short see . The resComments or questions about activities/objects item of the Relating to the environment construct. The results did not differ when analyzing the evolution of the four weeks versus the evolution between only the first and last week, with the same variables being significant in both comparisons.To analyze the significance of the changes in the evolution of behavioral and psychological symptoms during the sessions, a comparison was made between the mean/median scores of the Interact during items of the four weeks of intervention. As can be seen in Regarding the type of experience felt by the participants during the sessions, the evaluators recorded most of the sessions as leisure (32.98%), followed by relaxing (34.23%), stimulating (23.35), arousing curiosity (16.18%), and improving communication (6.43%). The researchers only perceived 6.32% of the sessions as unpleasant for the participants.p < 0.001, p < 0.001, There were significant changes between before and after the sessions in both physiological parameters see . ParticiThe purpose of this study was to examine the immediate effects of a four-week BLT intervention program on the behavior, mood, oxygen saturation, and heart rate of institutionalized older patients with moderate to very severe dementia. The main results revealed promising evidence of the benefits of BLT on specific aspects of mood and behavior in participants both during and after the sessions, as well as positive effects on the physiological parameters analyzed.As previously stated, mood and behavior were assessed using the Interact scale . AlthougTearful/sad and Talked spontaneously, and, on the other hand, a significant change in their stimulation level—specifically in the items Enjoying self, active or alert, and Relaxed, content or sleeping appropriately. Therefore, participants were less sad and less spontaneously talkative immediately after BLT sessions, which in turn could be related to the fact that they were also more relaxed, content, or sleeping appropriately. Concurring with some of these findings, other authors [The Interact short scores obtained by the participants before and after BLT sessions revealed, on the one hand, a significant decrease in the items of  authors  investig authors ,36,37, wMaking comments or asking questions about the activity item, which makes sense due to the habituation of the participants to the intervention program as it progressed. Scores on the Interact during also reflected that as the weeks of intervention progressed, the participants talked less clearly, sensibly, and spontaneously and with shorter sentences, i.e., an overall decrease in speech during the sessions. These results may also be linked to the lower post-session scores on the Talked spontaneously item of the Interact short. None of the existing studies on BLT in the literature address the immediate effects that occur within sessions, so we cannot discuss our results from the perspective of previous studies.The Interact during showed a significant decrease in the score of the Regarding physiological parameters, the measurements showed positive changes between before and after the sessions in the two analyzed parameters, with a significant increase in mean SpO2 and a significant reduction in mean heart rate. These changes may be related to the fact that participants were more relaxed, as shown by the Interact scores, since these biological responses are considered physiological indicators of a relaxation response ,39. ConsTo the best of our knowledge, the immediate impact of BLT sessions on mood and behavior has been virtually unexamined previously, so the present study provides novel and relevant data for clinical practice. However, the results of this work should be regarded as preliminary and interpreted with caution due to certain existing limitations. This study is one part of a larger and more comprehensive BLT investigation. The current study only analyzed the immediate effects during and after BLT sessions, and the long-term effects should be further established. Therefore, these limitations stem mainly from the small sample size and the use of a single-arm intervention with no control group, both of which limit the generalizability of the results found. Additionally, mood and behavior were measured based on the observations of unblinded researchers, which may have resulted in researcher bias. Future research should address these limitations by employing a double-blind design in controlled studies with larger sample sizes. Another physiological parameter (determination of blood pressure at least three times during the sessions) could also be used to further assess the impact of bright light therapy.The results of the present study suggest that a bright light therapy intervention program of 30-min sessions provides promising outcomes and immediate positive effects on mood, stimulation level, blood oxygen saturation, and heart rate. On the other hand, there was a tendency for a decrease in speech both during and after the intervention sessions. Further research is needed to strengthen these findings and to explore in depth the possible immediate effects of BLT.


The synergistic effect of oxygen vacancy as the center of a trap and p–n heterojunction forming an electric potential field at the interface is explained, and the mechanism of improving photocatalysis and gas sensitivity is analyzed. This work will provide an innovative vision for dual-performance oxygen vacancy modification of heterojunctions through photocatalysis.In this paper, ZnO/NiO composites rich in oxygen vacancies are prepared by the solvothermal method and reduction method. In the test, through the use of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscope (TEM), diffuse reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL), and electron paramagnetic resonance (EPR), we effectively prove the existence of phase, morphology and oxygen vacancies in the material. Through the photocatalysis test and gas sensitivity test, it is found that 10% Ni doped OZN-10 has the best photocatalytic activity and gas sensitivity characteristics. The degradation rate of methylene blue (MB) was 98%. The gas sensitivity test shows that OZN-10 has good selectivity, good response performance  and excellent response recovery time  for saturated NH Nanoparticles have attracted much attention because of their versatility, which can be used for photoelectric sensing, photocatalysis and gas sensor. Due to their large surface-to-volume ratio ,2,3,4, t5O2I/ZnO n–n heterojunction formed by calcination, which expanded the light response to the visible region and improved the separation efficiency of electron–hole pairs [2O nanoparticles and ZnO nanorods on the nickel foam (AZN) by combining hydrothermal and precipitation methods, successfully constructed three-dimensional mesh composites, and evaluated their photocatalytic performance under simulated sunlight. A series of photochemical test results show that the charge separation efficiency of AZN is significantly improved, which is attributed to the synergistic effect of direct Z-type heterojunction, matched band structure and three-dimensional porous structure [ZnO is an N-type semiconductor with a band gap of 3.37 eV. Therefore, it acts as a photocatalyst under UV irradiation ,7,8,9. Ile pairs . Song ettructure .O) and zinc (VZn) vacancies deserve special attention for a variety of reasons. First, they are considered to be the defects with the lowest formation energy in ZnO, so their presence in ZnO is likely and observable [−2 to produce superoxide radicals, which can oxidize NO to the final product nitrate [2 and ZnO effectively amplified the resistance changes caused by oxygen adsorption changes. Two-dimensional (2D) porous structures also play an important role in excellent sensing performance due to excellent electron transport capacity and abundant gas diffusion channels [Among the various defects observed in ZnO, oxygen , nickel nitrate hexahydrate (Ni(NO3)2·6H2O), caustic potash (KOH), ethanol, sodium borohydride, tert-butanol, isopropanol, and potassium iodide were obtained from the Macklin company .Ethylene glycol (EG), zinc acetate dihydrate (Zn(Ac)2 at a heating rate of 5 °C/min at 400 °C for 70 min. Then, the calcined powder was added to 1000 mL of deionized water. It was stirred well to dissolve the unreacted sodium borohydride and by-products. Finally, the precipitate was centrifuged, washed, and dried at 60 °C under vacuum to obtain OZN-5, OZN-10, and OZN-15. Afterwards, pure ZnO samples were prepared under the same conditions.The synthesis of nanosized oxygen vacancy zinc oxide/nickel oxide spherical particles is based on a previously reported modification strategy with ulterior motives. The specific synthesis process is shown in 2) and was used as the light source to test the photocatalytic activity of the prepared photocatalyst to decompose MB in XPA-7 photochemical reactor. A photoelectric integrated test platform was used to test the gas sensitivity performance . As shown in 2O2. Through the conversion of ppm and mass fraction, a certain amount of saturated liquid was injected into a 500 mL conical bottle and put into a drying oven for natural volatilization until complete, and then the bottle was removed. Both ends of the electrode piece were clamped with an electrode clamp, and the performance of the electrode piece at room temperature and standard atmospheric pressure was tested by the CGS-MT instrument, a rubber plug was used to maintain a high concentration of 3000 ppm in the conical bottle. The electrode was quickly inserted into the bottle for response recovery test and the change of the current resistance of the sample was observed.The morphological characteristics of the object were observed by scanning electron microscope ; a photoluminescence (PL) spectrometer  was used to judge the electron directional movement and electron-hole recombination; a transmission electron microscope  was used to determine the sample morphology, sample phase and sample 7 diffraction pattern; X-ray diffractometry  was used for the analysis of the sample phase; a UV-visible spectrophotometer  was used for liquid and solid UV analysis; and X-ray photoelectron spectroscopy  was used for elemental and valence band analysis. EPR strength was measured using an electron paramagnetic resonance spectrometer . Electrochemical impedance spectroscopy (EIS) was measured by ZAHNER-Im6ex  electrochemical workstation. The workstation adopts a three-electrode mode with 1m KOH solution as electrolyte, Ag/AgCl as reference electrode, sample as working electrode and platinum as counter electrode. Photocurrent was measured using a three-electrode system, electrochemical workstation  and xenon lamp . The photocatalytic workstation is equipped with a 350 W xenon lamp , (203) and (103), while the 2 inner rings are mainly characteristic crystal planes of nickel oxide (200) and (111). The above analysis confirmed the successful synthesis of nano-ZnO/NiO particle structure.3/2 and Zn 2p1/2, which are consistent with the state of Zn2+ in ZnO. We observed the strongest Zn 2p peak in pure ZnO, and the addition of nickel led to the weakening of the Zn 2p peak. It may be caused by the partial NiO covering on ZnO nanoparticles. In 3/2 852.87 eV indicates the presence of Ni3+. The remaining peaks indicate the presence of Ni2+, and the comparison between ZN and OZN shows that Ni3+ is also reduced to Ni2+ after the reduction in NaBH4. Compared with the Ni 2p peaks (2p3/2 and 2p1/2) of ZN nanoparticles, the Ni 2p peaks of OZN move towards the lower binding energy, which is about 0.6 eV. Traditionally, binding energy shifts in XPS spectra have been explained by two mechanisms: different electronegativity of metal ions and strong interactions between nanocrystals. The electronegativity of Ni2+ is about 1.91, which is about 0.26 than that of Zn2+. Ni2+ can absorb electrons from Zn2+, so the shielding effect of electrons on Zn2+ is reduced, but the shielding effect on Ni2+ is increased [O or VZn in the ZnO lattice accompanied by the doping of metal ions. The free competitive growth pattern of Zn–O and Ni–O bonds at the Zn–O–Ni interface leads to a large number of oxygen vacancies, and the lattice perturbation and reconstruction are induced by doping. In addition, the ionic radii of zinc and nickel are different, and the addition of Ni to ZnO nanoparticles leads to the destruction of the local equilibrium of the crystal structure. This causes an increase in internal stress in the main lattice, and in order to release the stress, oxygen vacancies need to be formed. In OZN-10, the strongly reductive NaBH4 was calcined in an N2 atmosphere. Compared with the previous two figures, we successfully introduced a large number of oxygen vacancies in ZnO/NiO. These data are in good agreement with previous reports on ZnO. Oxygen vacancies are introduced to the surface at high temperatures, hypoxia and reductive materials.The chemical composition and elemental states of pure ZnO, ZN-10 and OZN-10 samples were measured by X-ray photoelectron spectroscopy (XPS). ZN-10 and OZN-10 samples showed the presence of Zn, O, Ni and C in the whole XPS spectrum, and no other elements were found. The presence of component C is mainly attributed to its absorption in the atmosphere before XPS measurement. Zn 2p, O 1s, and Ni 2p in the high-resolution XPS are shown in ncreased . Thus, tncreased . As can αhv)2 = A(hv − Eg), with which the bandgap energy (Eg) is calculated, where α, hv and A are absorption coefficients, photon energy and constants. Therefore, the calculated band gaps of pure ZnO, ZN-5, ZN-10, ZN-15, OZN-5, OZN-10 and OZN-15 are 3.21, 3.18, 3.12, 3.17, 3.07, 2.88 and 2.92 eV, respectively. The order of band gap is consistent with the previous analysis; the band gap of OZN series is smaller than that of ZN series, and the introduction of oxygen vacancy is beneficial to enhance the light absorption [Diffuse ultraviolet-visible spectroscopy is used to study the optical adsorption performance of ZnO samples, and the corresponding spectra are shown in sorption . The add2+ doping, the emission of ZN and OZN is greatly inhibited. It is possible to increase the electron transfer rate between ZnO nanoparticles and Ni2+, thereby improving the interface interaction between them. Thus, the Ni2+ and oxygen defects inhibit electron–hole pair recombination and accelerate electron transfer.Photoluminescence spectroscopy is an effective method to study the electronic structure and optical properties of semiconductor nanomaterials. It can reveal the structural properties of materials, such as surface oxygen vacancy and defect, surface states, and separation and recombination of photogenerated carriers, thus providing a strong basis for the development and preparation of high-performance semiconductor functional materials. In 0) × 100%, where C0 is the initial MB concentration and absorbance before illumination, respectively, and C is the MB concentration and absorbance at t (min) after illumination, respectively. 0) = kt, where t is time (min). The rate constants k of pure ZnO, ZN-5, ZN-10, ZN-15, OZN-5, OZN-10 and OZN-15 are 0.22 × 10−2, 0.56 × 10−2, 0.67 × 10−2, 0.55 × 10−2, 0.65 × 10−2, 1.2 × 10−2, 0.8 × 10−2, respectively, and the reaction rate with OZN-10 was 1.2 × 10−2 min−1, which was about six times that of pure ZnO sample. The linear relationship confirmed that the photocatalytic behavior of MB was completely consistent with the quasi-first-order kinetics under these reaction conditions. This enhanced ability is attributed to the reduction in the recombination ability of electron hole pairs due to the potential plant of heterojunction generation. Additionally, it can be attributed to the narrow band gap extending the light response to the visible region. OZN has a small particle size in its structure, which can provide a large reaction space and numerous active sites. Because of the formation of surface oxygen vacancy defects, it has a good electron hole separation efficiency and long excitation life.Pure ZnO, ZN-5, ZN-10, ZN-15, OZN-5, OZN-10, and OZN-15 nanoparticles were used to degrade MB dye in order to evaluate the photocatalytic performance of the prepared ZN series and OZN series catalysts. We prepared 30 mg/L methylene blue solution and added 10 mg photocatalyst to it for reaction. The photodegradation rate was calculated by using the equation: D(%) =  and OH−/•OH (1.99 eV NHE), it can be concluded that the valence band potential of OZN-10 can cause H2O or OH− to produce •OH. On the other hand, the valence band conduction potential of OZN-10 is −0.23 eV, which is positive than O2/•O2− (−0.33 eV NHE), so •O2− cannot be formed, but is negative than O2/H2O2 (+0.69 eV NHE), so the reaction can be carried out. Under the excitation of visible light, H2O or OH− in the liquid produces •OH, and O2 reacts to generate H2O2 [2− and h+ were captured by isopropanol (IPA), p-benzoquinone (BQ) and potassium iodide (KI), respectively. After the addition of scavengers in the photocatalytic reaction system, the photodegradation rate of MB of KI and IPA decreased most evidently, and the photocatalytic activity of OZN-10 was inhibited. As it can be seen from the figure, the photocatalytic degradation efficiency of MB decreased by about 90% when holes and captured, indicating that holes and •OH are the main free radical substances in OZN-10 system, which matches the chemical potential analysis.According to the tangent line of data line obtained in ate H2O2 . Such do2−, which is very helpful in the depolymerization of intermediates into valuable products due to its moderate redox potential. On the other hand, because photoelectrons are captured effectively, electrons and holes are separated effectively. At the same time, the photogenic hole reacts with OH− in the solution to form •OH. Because •OH exhibits a high oxidation potential, it cannot selectively oxidize MB to intermediates and further oxidize to CO2 and H2O. In addition, photogenic holes can also oxidize MB directly into intermediates and further oxidize CO2. On the other hand, the introduction of oxygen vacancies not only improves the separation efficiency of optical carriers as trap centers, but also produces defect-related states near the valence band, resulting in a narrower band gap and enhanced light absorption. In fact, the doping of Ni2+ and the appropriate oxygen vacancy concentration promote the production of •O2− to a certain extent [2 and H2O [Based on the above discussion and previous studies, the degradation mechanism of MB by OZN-10 photocatalyst is shown in n extent . It is g and H2O . It is a3 gas was accurately measured at room temperature and standard atmospheric pressure to explore the role of oxygen vacancy and NiO doping, as shown in 2O2, were tested to explore the selectivity of the sensor. As shown in 3 is low, which is 0.2% of the response of saturated NH3. This can be attributed to the similar characteristics of the electrons of NH3. The other mentioned systems can be ignored and hardly affect the detection of NH3. OZN-10 showed good selectivity for ammonia gas. VO acts as the preferred adsorption site for NH3 molecules. It causes the extraction or capture of electrons from the conduction band, resulting in a change in resistivity. The more oxygen vacancies are produced, the more sensitive the gas is, because a higher concentration of NH3 molecules can be adsorbed. Oxygen vacancies provide additional electrons to participate in the response and recovery process, thus improving the adsorption of ZnO to gas molecules. Moreover, the formation of a p–n heterojunction at the interface between n-type ZnO and p-type NiO plays an important role in improving the performance. Due to the difference in band gap and Fermi level between the p-type NiO and n-type ZnO, they form a p–n heterojunction at the interface through charge carrier transport, thus increasing the barrier height and generating an additional depletion region [In order to prove that adding NiO and oxygen vacancy into ZnO nanoparticles is an effective method to enhance the gas sensitivity of ZnO-based gas sensors, the gas sensitivity of pure ZnO, ZN-10, OZN-10 and OZN-15 sensors were tested. Surveys were conducted separately. The sensor response to saturated NHn region . As a re3 were also found through gas sensitivity tests. The adopted synthesis strategy opens up interesting perspectives for the design of a p–n heterojunction and oxygen vacancy composite nanostructures for different types of applications, from selective sensor devices to high-performance photocatalysts.In conclusion, ZnO/NiO nanoparticles containing oxygen vacancy defects were prepared by the solvothermal reduction and high temperature reduction. The small particle size and large specific surface area of nanoparticles can greatly improve their optical, photocatalytic and gas sensitive properties. OZN-10 showed excellent photocatalytic performance driven by solar energy and almost completely degraded methylene blue. The degradation efficiency of OZN-10 is the highest among all the analyzed samples, and the amount of degradation within the same time is about twice of that of pure ZnO, which is related to the heterojunction structure and surface oxygen vacancy defects of OZN-10. In addition, the good response and selectivity of the material to NH


The underlying mechanism for the abnormal electrical performance was further demonstrated by X-ray photoelectron spectroscopy (XPS) detection and first-principles calculations. The analysis found that chemical bonds were formed between the oxide (O) of amorphous ZnO and the carbon (C) of graphene and that the transfer of the π electrons was restricted by C=O and C-O-C bonds. Given the above, this study further clarifies the mechanism affecting the photoelectric properties of amorphous composite films.Research on the preparation and performance of graphene composite materials has become a hotspot due to the excellent electrical and mechanical properties of graphene. Among such composite materials, zinc oxide/graphene (ZnO/graphene) composite films are an active research topic. Therefore, in this study, we used the vacuum thermal evaporation technique at different evaporation voltages to fabricate an amorphous ZnO/graphene composite film on a flexible polyethylene terephthalate (PET). The amorphous ZnO/graphene composite film inherited the great transparency of the graphene within the visible spectrum. Moreover, its electrical properties were better than those of pure ZnO but less than those of graphene, which is not consistent with the original theoretical research (wherein the performance of the composite films was better than that of ZnO film and slightly lower than that of graphene). For example, the bulk free charge carrier concentrations of the composite films (0.13, 1.36, and 0.47 × 10 Zinc oxide (ZnO) films underpin the development of solar cells ,2, gas sThe properties of ZnO/graphene composite films are different from those of the individual constituent materials. Experimental studies have been conducted on graphene composites with ZnO nanoparticles or nanorods ,28,29,30To understand the underlying mechanism of performance change, some scholars have studied crystalline ZnO/graphene via density functional theory (DFT). The results showed that by changing the layer spacing of ZnO/graphene, the carrier mobility of the system could be modulated , and theMost studies have focused on crystalline ZnO/graphene composite films, but amorphous ZnO/graphene composite films remain to be explored. Thus, there is the question as to whether an amorphous ZnO/graphene composite film would retain the high transparency and conductivity of graphene. In this work, through the vacuum thermal evaporation technique, an amorphous ZnO layer was deposited onto graphene/PET to form an ultrathin flexible composite film. There are many ways to prepare composite ZnO/graphene films. The cost of magnetron sputtering technology is high, the efficiency of chemical vapor deposition is low, and wastewater treatment by electrochemical plating is difficult and pollutes the environment. However, the vacuum thermal evaporation method has the advantages of low cost, fast evaporation rate, and environmental friendliness. Therefore, the evaporation method is the best choice .After preparation, we carried out relevant detection techniques and the optical and electrical properties of the amorphous ZnO/graphene composite film were characterized to clarify the unexpected results, i.e., the significantly lower electrical properties of the composite films compared with those of the graphene sheet. The interfacial chemical effect of amorphous ZnO/graphene was investigated and analyzed via X-ray photoelectron spectroscopy (XPS) and DFT calculations.−1 and 90%, respectively. Zinc oxide powder  was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., Shanghai, China.Graphene/PET composite film was purchased from 2D Carbon Graphene Material Co., Ltd., Changzhou, China . Double-layer graphene was grown via the chemical vapor deposition (CVD) of graphene on a PET substrate with 125 μm thickness. The sheet resistance and visible transparency of the graphene/PET were 157 Ω·sq−4 Pa at room temperature. Zinc oxide powder was placed onto a tungsten (W) boat, which was 160 mm below the substrate. Amorphous ZnO layers with different thicknesses of 40, 75, and 160 nm were thermally evaporated under different evaporation voltages , i.e., the voltage applied on the tungsten boat as a heating source, and the rate of voltage increase was 5 V/min. A schematic diagram of the parallel resistance of amorphous ZnO/graphene composite film and the technological parameter graph of the deposition process are shown in The fresh graphene/PET flexible substrate was transferred into the vacuum chamber for ultrathin ZnO layer evaporation at a pressure of 8 × 102 samples in a square shape. The electrical properties of the composite films were measured using a HALL 8800 Hall-effect measurement device, which was carried out in four-point mode with gold electrodes by DC voltage in a 4800-gauss magnetic field. The transmittance of composite films was measured using a CARY 5000 UV–VIS–NIR spectrometer in the wavelength region of 175–3300 nm (test coverage: 200–800 nm).The samples were cut into 10 × 10 mm+ sputtering gun at 1 kV with an etching rate of 3 nm/min for standard SiO2.The thicknesses of the ZnO layers were measured using a KLA-Tencor Alpha-Step D-100 profilometer at a speed of 0.03 mm/s and stylus force of 0.03 mg. The roughness of the substrate was measured by atomic force microscopy (AFM CSPM5500), and the roughness was analyzed using Imager software. The samples were scanned in contact mode using a Tap300Al-G probe under ambient atmosphere. The surface morphologies of the film were obtained using a SIGMA high-definition field-emission scanning electron microscope, which was operated at 15 kV. The X-ray diffraction (XRD) patterns of the composite film were recorded using an X’Pert powder X-ray diffractometer with monochromatized Cu Kα radiation. The tube was operated at a scanning speed of 0.05°/s from 20° to 60°. The structures of graphene and ZnO/graphene composite film were characterized by transmission electron microscopy (TEM) at 200 kV. The TEM samples were prepared by scratching the ZnO and graphene layers and placing the minimal debris onto amorphous carbon-coated cooper grids. The element distribution and the interfacial chemical bonds were analyzed via a PHI Quantera SXM scanning photoelectron spectrometer, using an ArThe Vienna ab initio simulation package (VASP) code was used to calculate the electron localization function (ELFCAR) of the interfacial models of amorphous ZnO and graphene. In VASP, the interactions of electrons and ions were described by their projector-augmented wave (PAW) potentials. The generalized gradient approximation parametrized by Perdew–Burke–Ernzerhof was used for the electron exchange–correction function.6 was obtained after structural optimization. Similar models have been mentioned in other studies [In this study, the initial structures of the amorphous ZnO/graphene interface model were investigated. A cluster model of (ZnO)n was selected to represent the amorphous ZnO model. To better match the (ZnO)n clusters and graphene, n was chosen to be 6, so that the model had 6 Zn atoms and 6 O atoms. The cluster model of (ZnO) studies ,42,43.104s2, O 2s2p4, and C 2s22p2.The structure of crystalline ZnO (2 × 2 × 1) was obtained from the Materials Project database, with code number 2133; the crystalline ZnO had a P63mc space group symmetry. The structure of graphene (2 × 2) was obtained from the Materials Project database, with the code number 990448; the graphene had a P6/mmm space group symmetry. The valence electron configurations were Zn 3dThe two interface models were established. −5 eV, and the width of the Gaussian smearing was 0.05 eV. A Monkhorst-Pack 5 × 5 × 5 k-point mesh was used for the Brillouin zone integration to compute the electron localization function.The cut-off energy in this calculation was 500 eV. The convergence threshold for self-consistent-field iteration was set at 10The surface morphological structures of the bare graphene and amorphous ZnO/graphene composite films are displayed in It is worth mentioning that the range of ZnO particle sizes of the film with 40 nm thickness was from 10 nm to over 50 nm. The roughnesses of the graphene and the films with thickness of 40, 75, and 160 nm were 5, 46, 49, and 77 nm, respectively. This proved that the ZnO film with 40 nm thickness was un-continuous. The ZnO films with thicknesses of 75 nm and 160 nm were dense and continuous.The phase structures of the bare graphene and ZnO/graphene composite film were characterized by XRD, and the results are shown in From the X-ray diffractometer (XRD) patterns a, the inIn addition, there is no (002) diffraction peak at 34.40° in The transparent spectra of the graphene/PET and amorphous ZnO/graphene/PET are displayed in 5Ω·sq−1, while the carrier concentration and mobility are as low as 1017 cm−3 and 6-10 cm2·v−1·s−1, respectively.t = 1/RZnO + 1/Rgraphene [17–18 cm−3) were remarkably lower than that of bare graphene (1020 cm−3). To determine the mechanism of the loss of free charge carriers in the ZnO/graphene composite film, we focused on the interfacial chemical effect of amorphous ZnO/graphene. The continuous and dense ZnO layer makes relatively little contribution to the sheet resistance of the composite film. The parallel resistance of the graphene and ZnO layers was equivalent to that of a single resistor; that is, 1/Rgraphene . Accordigraphene . HoweverThe above mentioned amorphous ZnO/graphene/PET films exhibited unexpectedly deteriorative electrical properties. The amorphous ZnO/graphene/PET sample with ZnO thickness of 75 nm was selected for XPS analysis, which provided the elemental composition and bonding information.+ ion bombardment did not damage the graphene hexahedral structure [The distributions of C, O, and Zn elements at different depths of the ZnO/graphene/PET composite film are shown in tructure ,50,51; tThe XPS C1s and O1s spectra were fitted by the Gaussian–Lorenzian (GL30) functions to reveal the chemical bonding state of the carbon and oxygen a–f. CasaThe binding energies of O1 at 530.0–531.6 eV overlapped and were identified as C=O and C-O bonds; the binding energies of O2 and O3 at 532.4–533.3 eV were identified as C-OH . The two−4 Pa; that is, the oxygen not bonded with the C of the graphene was pumped away. Third, the oxygen atoms in the chamber were only provided by ZnO molecules.One may argue that the oxygens of C=O and C-O came from pollution of the graphene surface because the graphene was used as received, without surface cleaning by the sputtering process. Although it is possible that the oxygen came from surface pollution, the possibility is low, due to the following reasons: First, the graphene was kept in a vacuum bag before use. Second, the fresh graphene was placed in a vacuum chamber, the pressure of which was as low as 10When the ZnO powder was evaporated by the vacuum thermal technique, there were ZnO molecules or clusters between the hot tungsten boat and cold graphene/PET substrate. There was not enough energy for ZnO molecules to crystalize, and therefore, the films remained amorphous. The oxide (O) in ZnO molecules was attracted by the carbon (C) in graphene according to the first-principles calculations, which resulted in the formation of C=O and C-O-C bonds.In general, the formation of C=O and C-O-C bonds at the interface of amorphous ZnO/graphene caused the bonding of the π electrons of the graphene and thereby limited their mobility. In other words, the formation of C=O and C-O-C bonds should be responsible for the decrease in the bulk free charge carriers in the amorphous ZnO/graphene composite film, which is contradictory to earlier studies on crystalline ZnO/graphene composites. Therefore, we believe that the amorphous structure of the ZnO layer is the cause of the formation of the C=O and C-O-C chemical bonds.The electron localization functions (ELFs) were calculated to further investigate the bonding natures at the crystal a and amo18 cm−3 corresponding to composite films with thickness of 40, 75, and 160 nm) were remarkably lower than that of bare graphene (964 × 1018 cm−3) and better than that of ZnO (0.10 × 1018 cm−3). The results from XPS analysis showed the formation of C=O and C-O-C bonds between O from ZnO and C from graphene at the interface of ZnO and graphene. The first-principles calculations revealed that the oxide from amorphous ZnO tended to be attracted by C from graphene to form strong, dense localized electron clouds. The electrical properties of the composite films deteriorated because of the formation of the C=O and C-O-C chemical bonds at the interface of amorphous ZnO/graphene, which restrained the transfer of the π electrons from graphene. This discovery is still helpful for the development of transparent conductive films.In this study, amorphous ZnO layers on flexible graphene/PET substrates were prepared via vacuum thermal evaporation at room temperature. With the increase in the amorphous ZnO layer thickness, the morphological structure of the layer changed from loose un-continuous granular, to relatively dense granular, to continuous and dense. The transparency of the composite films within the visible spectrum was comparable to that of graphene/PET. Its electrical properties were better than those of the pure ZnO but less than those of graphene. For example, the bulk free charge carrier concentrations of the composite films (0.13, 1.36, and 0.47 × 10


A hybrid structure composed of periodic monolayer graphene nanoribbons and a dielectric multilayer structure was designed to generate a Fano resonance (FR). The strong interaction between the surface plasmon resonance of graphene and the dielectric waveguide mode results in the FR. The finite element method is utilized to investigate the behaviors of the FR, and it matches well with the theoretical calculations using rigorous coupled wave theory. The results demonstrate that the profile of the FR can be passively tuned by the period of the graphene nanoribbons and actively tuned by the Fermi level of the graphene. The decoupled nature of the FR gives it potential applications as a self-calibrated refractive index biosensor, and the sensitivity can reach as high as 4.615 μm/RIU. Thus, this work provides a new idea for an excellent self-referencing refractive index biosensor. The surface plasmon polariton (SPP), a surface evanescent wave formed by the interaction of free electrons and photons on the surface of a metal or an insulator, has been regarded as the information carrier in micro-nano optics with the most potential. As the SPP can break through the diffraction limit in traditional optics and support the propagation of light in acceptable wavelengths, it has promoted the development and manufacturing of optical devices ,2. In adGraphene, emerging as a promising plasmon material, has been studied intensively due to its excellent photoelectric properties, including low losses, tight field localization, broad response spectrum, and flexible tunability. The extraordinary plasma properties of graphene make it active in various coupling systems, such as plasmon-induced transparency ,5 and FaIn this work, we proposed a hybrid structure constructed by periodic monolayer graphene nanoribbons and a dielectric waveguide to realize an active tunable FR, where the waveguide mode supports the narrow resonance, and the graphene plasmon provides the broad resonance. An FR with a high-quality factor can be observed when the graphene SPR is coupled with the waveguide mode. The finite element method  was utilized to simulate the behaviors of the FR. To confirm the accuracy of the results, the results were also calculated by rigorous coupled wave theory (RCWA) ,25. The 2, with the refractive index n1 = 1.3; the PWG core is set to be Ge with the refractive index n2 = 4. The thickness of each layer is set to be d1 = 1.2 μm and d2 = 2.8 μm, respectively. Then, the FR can be excited at the response wavelengths when the transverse magnetic (TM) light is incident on the structure with an incident angle θ. For the experimental fabrication of this structure, the dielectric multilayer can be prepared by the electron beam deposition method. The monolayer graphene can be grown by chemical vapor deposition (CVD) and transferred onto the planar waveguide. Then, the monolayer graphene can be utilized to fabricate the graphene nanoribbons by the atomic-force-microscope- (AFM) based lithography method [y method .ω is the angular frequency, ε0 is the vacuum permittivity, dg = 0.34 nm is the thickness of the monolayer graphene, and σ is the surface conductivity of the graphene constructed by intraband σintra and interband σinter, described as [Bk is the Boltzmann constant, ћ is the reduced Planck constant, T expresses the absolute temperature of the environment, e is the elementary charge, and the carrier relaxation time τ is expressed as fv, the carrier mobility μ, and the Fermi energy FE. In this work, the Fermi velocity was set to be 2/Vs.As is mentioned above, the FR is achieved by the coupling between a broad resonance and a narrow resonance. In this hybrid structure, the graphene nanoribbons were utilized to excite a surface plasmon resonance as the broad resonance. In ribed as (1)σintrk0 is the wave vector of the plane incident wave in free space, β is the propagating constant, and m is the mode order of PWG. By solving equation (3) and neff = β/k0, the effective refractive index was obtained and was plotted as the red solid line in β = k0sinθ ± 2nπ/Λ. Hence, the theoretical resonant wavelength of the waveguide mode could be easily derived. With the incident angle θ = 0°, the period Λ = 4 μm, the waveguide mode order m = 0, and the diffraction mode order of grating n = 1, the resonant wavelength was calculated to be 13.24 μm, which was depicted in The narrow resonance was provided by the waveguide mode in this coupled system. In order to make the waveguide mode couple with the GSPR, we calculated the dispersion of the PWG mode to obtain the resonance wavelength of the waveguide mode, and the dispersion is expressed as (3)n22k0FE of the graphene was tuned from 0.95 eV to 0.99 eV. The reflection spectra were simulated by the FEM (black solid line) and theoretically calculated by the RCWA (red dash line), as seen in λ = 13.164 μm, indicating the graphene SPP. As seen in To investigate the dynamic tunability of the FR in the proposed structure, the Fermi energy n from 1 to 1.02, as shown in n, while the wavelength of the right resonance was almost fixed. It promises a potential application for self-referencing RI sensors. In this sensing system, the right resonance works as a reference signal, and the absolute RI can be measured according to the calibration curve when the calibration samples are introduced. We plotted the change curve of the resonant wavelength versus n in S = Δλ/Δn, can be as high as 4.615 μm/RIU, which is significantly better than the sensors presented in Refs. [According to the previous studies ,12, FRs in Refs. ,27,28. TIn summary, we proposed an actively tuned FR constructed by periodic monolayer graphene nanoribbons hybridized on a distributed planar waveguide. In this structure, the periodic monolayer graphene nanoribbons can not only excite the graphene SPPs, but can also work as a grating to provide the momentum-matching condition for exciting the waveguide mode. The FR can be observed when these two modes are coupled with each other. The influences of the period and groove of the periodic monolayer graphene nanoribbons on the shape of the FR were discussed and it was found that the period and groove of the periodic monolayer graphene nanoribbons played a crucial role in the FR shape. In addition, the studies have shown that the shape of the FR can be tuned dynamically by the Fermi energy of graphene. Finally, we applied the results to the self-referenced RI sensor, and its sensitivity could reach 4.615 μm/RIU. Thus, this work provides a new idea for an excellent self-referencing RI sensor.


These results are in agreement with EARL reference values for fluorine-18 PET. The results in this work showed that accurate quantitative scandium-43/44 PET/CT is achievable in commercial devices. This may promote the future introduction of scandium-43/44-labelled radiopharmaceuticals into clinical use.Scandium-44 has been proposed as a valuable radionuclide for Positron Emission Tomography (PET). Recently, scandium-43 was introduced as a more favorable option, as it does not emit high-energy γ-radiation; however, its currently employed production method results in a mixture of scandium-43 and scandium-44. The interest in new radionuclides for diagnostic nuclear medicine critically depends on the option for image-based quantification. We aimed to evaluate and compare the quantitative capabilities of scandium-43/scandium-44 in a commercial PET/CT device with respect to more conventional clinical radionuclides . With this purpose, we characterized and compared quantitative PET data from a mixture of scandium-43/scandium-44 (~68% scandium-43), scandium-44, fluorine-18 and gallium-68, respectively. A NEMA image-quality phantom was filled with the different radionuclides using clinical-relevant lesion-to-background activity concentration ratios; images were acquired in a Siemens Biograph Vision PET/CT. Quantitative accuracy with scandium-43/scandium-44 in the phantom’s background was within 9%, which is in agreement with fluorine-18-based PET standards. Coefficient of variance (COV) was 6.32% and signal recovery in the lesions provided RC In this regard, the availability, transport, dosimetry, and safety are critical aspects to be addressed FDG.From the images obtained, it can be seen that the noise , noise (COV) and effect of scatter corrections were initially evaluated, as well as in the average residual lung error. For the COV, with similar activity ratio between spheres and background (rSC, gallium-68 with aSC, scandium-43/44 with rSC, scandium-43/ 44 with aSC, scandium-44 with rSC and scandium-44 with aSC, respectively. All levels were <15%, as recommended for fluorine-18 [With regard to the PET/CT capabilities, the device quantification (background calibration—ckground , all radorine-18 ,13,14,17BGcal, based on the acceptable deviation of 10% between measured and known background activity concentration [aSC and scandium-44 with rSC were outside tolerance levels. Interestingly, in contrast to Lima et al., the Biograph Vision produced acceptable results for scandium-44 when using aSC compared to their results with the Biograph mCT. As discussed by Lima et al. and confirmed by the current results (SC overcorrects the scatter contribution, due to the presence of the high-energy γ-radiation (SC. Overall, using the optimal SC, a BGcal below 10% was achieved with 2.7%, 3.1%, 8.0% and 2.9% for fluorine-18 and gallium-68 with rSC, for scandium-43/44 with rSC and for scandium-44 with aSC, respectively.Regarding the ntration , only sc results , relativadiation , which rCOV results, aSC tended to under correct for scatter events. This was also observed in the average residual lung error, where all reconstructions with aSC showed an increased lung error in comparison with the rSC. Notably, even for the worst results, which were obtained for the scandium-43/44 mixture with aSC, the average residual lung error was <15%, which is comparable to acceptable performance for fluorine-18 [Additionally, the impact of these corrections was evaluated in the lung region of the phantom. Knowing that there is no activity in the lung region, measurements of average residual lung error provide an assessment on the impact of the scatter and attenuation corrections in the final image. As shown previously in the meanRC and maxRC were superior when using fluorine-18 compared to the other radionuclides. This can be explained by the pure positron emissions and corrections tailored to this radionuclide. Comparing the scandium-43/44 mixture to pure scandium-44, the RC results were comparable to gallium-68—a more widely used radionuclide.As a final parameter, the recovery coefficients obtained for all radionuclides were investigated. Both COV and RCs.Although having differences in phantom preparation and data analysis between the current measurements and NEMA or EARL, namely, the activity concentration between background and lesions, it is felt that the comparison is still meaningful for 177Lu or 90Y-labeled counterparts. Importantly, delivery of scandium-44 and scandium-43 to PET centers without a cyclotron will be feasible over long distances and, thus, be of particular interest in countries in which the hospitals are far away from the production centers. The final optimization step refers to the use of a mixture of scandium-43/44 versus the use of scandium-44 only, as it can add to the reduction of an unnecessary dose to the producing personnel as well as the patient. Based on the current investigation, there is no obvious disadvantage of using a mixture of scandium radioisotopes. Hence, the concept could be translated to clinics without concern.In this work, the PET/CT quantification capabilities for scandium-43/44 mixture in relation to radioisotopically pure scandium-44, fluorine-18 and gallium-68 were evaluated using a high-end SiPM PET/CT device. It was demonstrated that it could be achieved with either a mixture of scandium-43/44 or pure scandium-44 using a SiPM similar quantitative performance to clinically used radionuclides such as gallium-68 and fluorine-18. This situation will not only enable the clinical translation of scandium-44; it also raises hopes that scandium-43 can be used clinically, in spite of the fact that it cannot easily be prepared in radionuclidically pure form. Scandium radioisotopes benefit from longer half-lives than conventionally used PET nuclides such as gallium-68 and fluorine-18, which may benefit from clinical evaluation where a scan start can occur at later time points when background activity is already cleared. Moreover, scandium may be used for prospective dosimetry prior to therapy with


Purpose: Ketamine is an anesthetic in clinical, but it has also been used as an abusing drug due to its low price and hallucinogenic effects. It is proved that ketamine abusing would cause multiple system damage including the urinary system, which is called ketamine-induced cystitis (KIC). Bladder fibrosis is late stage in KIC and threaten abusers’ life. This study aimed to investigate the molecular mechanism of ketamine-induced bladder fibrosis.Methods: Female Sprague Dawley (SD) rats were randomly divided into 3 groups. 2 groups were treated with tail vein injection of ketamine  for 12 weeks, whereas the control group was treated with normal saline solution. In each group, rat bladders were extracted and samples were examined for pathological and morphological alterations via hematoxylin and eosin (HE) staining, Masson’s trichrome staining and immunohistochemistry (IHC). SV-HUC-1 cells were treated with different concentrations of ketamine solution . Rat bladder and SV-HUC-1 cells were extracted protein and RNA for Western blot and RT-PCR detection. Metadherin (MTDH) siRNAs and overexpression plasmids were used to knock down and overexpress the relative genes. P38 mitogen-activated protein kinase (MAPK) inhibitor was utilized to inhibit the MAPK pathway.Results: Rats in the ketamine group exhibited fibrosis compared to rats of the control group and fibrosis were also markedly upregulated in SV-HUC-1 cells after treated with ketamine, which were ketamine concentration-dependent. After treating with ketamine in SV-HUC-1 cells, there was an increase expression of MTDH, epithelial-mesenchymal transition (EMT) markers, P38 MAPK. MTDH knockdown would suppresses P38 MAPK/EMT pathway to inhibit fibrosis, however, MTDH overexpression could promote the pathway in SV-HUC-1 cells.Conclusion: In rats and SV-HUC-1 cells ketamine-treated models, MTDH can regulate EMT through the P38 MAPK pathway to regulate the process of bladder fibrosis. Ketamine, also known as K powder, is an N–methyl–D–aspartate receptor antagonist . KetaminMetadherin (MTDH), which is also known as astrocyte upregulation factor −1 (AEG-1), was found in primary human fetal astrocytes after being treated with TNF-α or infected with HIV-1 . As a muThe function of MTDH is gradually being recognized in fibrotic diseases. In the study of the unilateral ureteral occlusion (UUO) model, it was found that MTDH can promote renal fibrosis by regulating the EMT . PreviouThe specific mechanism of bladder fibrosis after ketamine abuse is unknown. We hypothesize that MTDH is a key regulatory molecule, and it can regulate the process of bladder fibrosis by regulating EMT. In this study, the expression of MTDH and EMT marker proteins were detected in human bladder cell biochemistry Pillon (SV-HUC-1) cells and bladder tissue of rat models. Then, the expression of MTDH was regulated to study its regulatory effect. We provided evidence that the pro-fibrosis effect of MTDH is partly attributable to the promotion of the EMT by activating the P38 MAPK signaling pathway.All the experimental animals were performed on specific pathogen-free (SPF) female Sprague Dawley (SD) rats  weighing between 200 and 250 g. A total of 24 SD rats were randomly distributed into three groups, eight rats per group, and received tail vein injection of normal saline solution (control group), tail vein injection of 25 mg/kg/day ketamine hydrochloride solution  (low dose ketamine group), tail vein injection of 50 mg/kg/day ketamine hydrochloride solution (high dose ketamine group) for 12 weeks. The rats were weighed weekly to adjust the dosage of ketamine hydrochloride solution. Animals were raised at the Experimental Animal Center of Central South University  and the animal experiments were approved by ethical review of experimental animal welfare in Central South University (NO: 2018sydw0225).The bladder tissue which was removed from the rats in the ketamine group and control group was fixed in 4% paraformaldehyde overnight, embedded in paraffin blocks, and sliced into a 4 μm section. Hematoxylin and eosin (H&E) and Masson trichrome staining (MTS) were performed to carry out the histopathologic evaluation such as the morphology and inflammatory cell infiltration of the bladder, the distribution of collagen. Immunohistochemical staining (IHC) was performed to evaluate the fibrosis, MTDH expression, EMT markers of the bladder in ketamine group rats compared with the control group. Briefly, embedded bladder tissue was first deparaffinized and then subjected to a microwave oven for antigen retrieval in citrate buffer. The sections were incubated overnight at 4°C in rabbit MTDH antibody , mouse E-cadherin , mouse vimentin , rabbit fibronectin antibody , and rabbit collagen I antibody  after being blocked with 3% H2O2. And then the sections were incubated with biotinylated secondary antibody  for 30 min at room temperature, and development was achieved with 3,3′-diaminobenzidine.The human bladder cell biochemistry Pillon (SV-HUC-1) was obtained from Guangzhou Cellcook Biotech Co., Ltd.  and cultured in F-12K medium  containing 10% fetal bovine serum  at 37°C constant temperature and 5% CO2. SV-HUV-1 was stimulated with ketamine solution  diluted by medium for 48 h. The SB203580  was treated with SV-HUC-1 in the corresponding group.® INC., Suzhou, China) and C1000 Touch Thermal Cycler, CFX96 Real-Time System (Bio-Rad) according to manufacturer’s instructions. The results were calculated by the 2−ΔΔCt method and data are expressed as a ratio of the control gene GAPDH.Total RNA was extracted from SV-HUV-1 cell lines using RNAiso Plus reagent  and cDNA was synthesized using PrimeScript™ RT reagent kit . The primers designed details were shown in ® software.The SV-HUV-1 cells and bladder tissues were lysed with RIPA  containing protease cocktail  to obtain the total protein. The protein was separated and transferred via cataphoresis using 10% SDS-PAGE gel electrophoresis and PVDF membranes. The primary antibodies against rabbit MTDH antibody , mouse E-cadherin , mouse vimentin , rabbit P38 , rabbit P-P38 , rabbit fibronectin , rabbit collagen Ⅰ , rabbit α-SMA , mouse Flag-Tag  and GAPDH  were incubated with the membranes overnight at 4°C. After incubating, blots were detected by secondary antibody and visualized by the ECL assay (Milliporesigma) and the bands were analyzed with Image JSV-HUC-1 was seeded in a 6-well cell culture cluster. MTDH siRNA and MTDH overexpression plasmid were bought from Sangon Biotech  and the details of the sequence are in SV-HUC-1 cells were inoculated into 96-well plates (1 × 104 cells/well) for 24 h, and then stimulated with ketamine solution (0.1–2 mmol/L) diluted by medium for 48 h. After ketamine treatment, CCK-8 solution  was added to the 96-well (10 ul/well) and incubated with SV-HUC-1 for 2 h, the absorbance at 450 nm was detected via a microplate reader .The urination spot test spot test was performed in a metabolic cage. The test paper used for urine spots was a customized test paper that turns red when exposed to urine, which could accurately indicate the liquid infiltration. Twelve weeks after the injection of ketamine and 0.9% saline, the rats in the experimental group and the control group were moved into a metabolic cage to collect urine. The urine spot test was carried out from 8 am to 12 o’clock in the morning.After anesthesia, the rats were fixed in the supine position, and 75% ethanol was used to disinfect the skin of the abdomen and perineum. After connecting each end of the cystometry tube and the three-way tube and venting the air, they were inserted into the bladder along the urethra of the rat. Gently press the rat’s abdomen to empty the bladder of residual urine. After the computer point signal was reset to zero, the micro-injection pump was turned on, and the normal saline preheated to 37°C was continuously perfused at a rate of 6 ml/h. Observe the urinary interval by observing the fluid outflow interval of the external urethra; by observing the number of times the water pressure is higher than the baseline 10 cm water column within 3 min before the leakage of urine to obtain the frequency of unstable contraction of the bladder detrusor.p < 0.05 or less was considered to be statistically significant.SPSS 20.0  was utilized to perform the statistical analyses. Data were shown as mean ± standard error of the mean (SEM) according to the results of three independent repeated experiments. Two-way analysis of variance (ANOVA) was used to analyze the differences. in vitro. After 48 h of treatment, the viability of SV-HUC-1 cells cultured with 1.5 mmol/L ketamine was significantly decreased (p = 0.01). And the urodynamics test showed that in the ketamine-induced cystitis rat model group, the frequency of urination increased, the interval between urination was shortened, and the unstable contraction increased  on SV-HUC-1 cells using a CCK-8 kit to evaluate the cytotoxicity of ketamine ecreased , indicatecreased . With thecreased . And we ecreased , the resecreased . Compareecreased . And we ecreased . In addincreased . The aboTo elucidate the underlying mechanism of ketamine-induced fibrosis, MTDH and EMT markers expression were investigated. Compared with the control group, the protein and RNA expression of MTDH and vimentin were increased, and the expression of E-cadherin was decreased in SV-HUC-1 cells after ketamine treatment . SimilarWe further investigated the role of MTDH in ketamine-induced bladder fibrosis by MTDH knockdown or overexpression. Successful MTDH knockdown was confirmed by WB analysis. MTDH expression in SV-HUC-1 cells was shown an obvious decrease following the knockdown . Small iTo investigate whether MTDH regulates EMT through the P38 MAPK pathway to promote bladder fibrosis, we measured the expression of P38 and phosphorylated (P)-P38 protein in SV-HUC-1 and rat bladder after ketamine treatment. In comparison with the control group, the expression levels of P-P38 protein were shown to be significantly increased in the ketamine treatment group, while there was no significant changes in the expression of P38 protein . When P3In the present study, underlying mechanisms of ketamine-induced bladder fibrosis were studied using SD rats and SV-HUC-1 cells. Our results suggested that EMT is an important process of bladder fibrosis. Furthermore, we also found that a novel pro-fibrotic molecule MTDH can regulate EMT through the P38 MAPK signaling pathway involved in bladder fibrosis induced by ketamine. MTDH might be a potential biomarkers in detection ketamine induced bladder fibrosis.Since it was first reported in 2007, a large number of the literature revealed that long-term use of ketamine can cause damage to the urinary system . DecreasEMT is involved in a variety of biological processes, such as tissue repair and pathology, including cancer and cataract . It alsoMost of the current research on MTDH focuses on its role in tumors. Previous studies have shown that MTDH can activate several classic cancer-promoting signaling pathways, such as EMT, NF- κ B and MAPK to enhance tumor progression and metastasis . It has Studies have found that P38 MAPK is closely related to myocardial fibrosis, pulmonary fibrosis, and liver fibrosis . Pirfeniin vitro, but in vivo, we did not study the mechanism of MTDH as a key molecule of ketamine induced bladder fibrosis and its possible target for the treatment. However, we revealed that MTDH might be a vital biomarker and treatment target of ketamine induced bladder fibrosis.In this study, we demonstrated that ketamine induced bladder fibrosis involves pathway MTDH/P38 MAPK/EMT. But the study has limitations as follows (I) Clinical investigation and data were not included in the present study. And the expression level of MTDH/P38 MAPK/EMT pathway markers were not detected in clinical bladder samples and this awaits further studies (II) We mainly verified the MTDH/P38 MAPK/EMT pathway In conclusion, we revealed that in rats and SV-HUC-1 cells models, MTDH can regulate EMT through the P38 MAPK pathway to partly regulate the process of bladder fibrosis. MTDH may serve as a novel biomarker and therapeutic target in bladder fibrosis induced by ketamine abuse.


To determine the international reliability and validity of the modified Radiographic Union Scale for Tibial fracture (mRUST) scoring method for open tibial shaft fractures based on ratings of radiographs by separate groups of North American and Tanzanian surgeons.Seven North American and 9 Tanzanian surgeons viewed 100 pairs of AP and lateral radiographs of open tibial shaft fractures obtained in Dar Es Salaam, Tanzania. The radiographs showed 25 patients’ fractures at 4 time points postfracture after treatment with either external fixation or intramedullary nailing. Surgeons evaluated each fracture using the mRUST scoring method and indicated their confidence that the fracture was healed on a scale from 1 to 10. Reliability of mRUST was determined using inter-rater agreement among North American and Tanzanian surgeons. Validity was determined via analysis of correlation between mRUST scores and EQ-5D-3L index scores at each time point postfracture.mRUST scores demonstrated strong reliability overall (ICC = 0.64) as well as within each group of North American (ICC = 0.72) and Tanzanian (ICC = 0.69) surgeons. Reliability was stronger for external fixation than for intramedullary nailing cases. mRUST scores were significantly correlated with overall healing confidence at all time points and with quality of life at 6 months and 1 year postfracture. mRUST scores also correlated significantly with patients’ quality of life scores (EQ-5D index) at 6 months and 1 year postfracture.North American and Tanzanian surgeons exhibited strong agreement in rating open tibial shaft fractures. Using mRUST scores is a valid means of assessing radiographic healing of tibial fractures in austere environments like Tanzania. A crucial consideration in treatment of tibial fractures is evaluation of fracture healing. However, defining and measuring healing status remains controversial. Currently, there are no universally accepted “gold standard” measures of union or nonunion. This contributes to significant variability among surgeons in terms of the methods they use to determine nonunion and how quickly they elect to perform corrective surgery for nonhealed fractures. The lack of consensus about healing assessment makes it difficult for physicians to make accurate and unbiased assessments of fracture healing status.Approximately half a million patients suffer from tibial fractures in the US every year. and modified RUST (mRUST) scoring tools to assess healing status of tibial fractures using radiographic analysis. These tools use the presence of bridging callus and obliteration of fracture lines on anteroposterior (AP) and lateral radiographs in order to assign a numerical value for a healing tibial shaft fracture. In the standard RUST instrument, raters are asked to score each of 2 cortices visible on both AP and lateral radiographs of a tibial fracture. Each of the 4  cortices is scored based on the following guidelines: 1 = no callus, 2 = bridging callus, 3 = remodeled. For mRUST, a fourth option  was added to the rating scale to differentiate between nonbridging and bridging calluses. This corresponds to a rating system of 1 = no callus, 2 = callus present, 3 = bridging callus, 4 = remodeled. Scores range from 4 to 12 (for standard RUST) and 4 to 16 (for mRUST), with lower scores indicating a less healed fracture and higher scores suggesting a more advanced stage of healing. The reliability (agreement in scoring among surgeons) and validity (correlation between scores and patient-relevant outcomes) of RUST and mRUST have been demonstrated in several studies.,6,7More recently, researchers developed the standard Radiographic Union Scale for Tibial fractures (RUST)However, important gaps in the literature remain. First, the mRUST scoring system has never been validated internationally, as studies to date have focused on North American surgeons’ assessments of fractures. Secondly, evidence linking mRUST scores to clinically relevant patient outcomes remains limited. Finally, a minimum mRUST score threshold below which fractures can be considered “not healed” with confidence has not yet been established. This lower threshold could inform surgeons’ decisions about whether or not to perform surgery. Moreover, because clinical trials typically follow nonunions as endpoints in fracture repair studies, a nonunion threshold is also useful for research purposes. which randomized patients with Gustilo-Anderson type I-IIIA open tibia fractures to treatment with either definitive external fixation or intramedullary nailing. The purpose of the present study was to evaluate the reliability of mRUST scoring of open tibial shaft fractures between North American and Tanzanian surgeons, and to correlate mRUST scores with both patients’ health-related quality of life and surgeons’ overall assessment of fracture healing, at 4 time points after fracture stabilization. Additionally, we sought to identify upper and lower mRUST score thresholds that correspond with healed fractures and not healed fractures, respectively.This study addresses these gaps in the literature using data from a recently completed randomized control trial in Tanzania,2In this study, AP and lateral radiographs of open tibial shaft fractures were evaluated by 16 experienced orthopaedic trauma surgeons practicing at major urban medical centers in either North America (n = 7) or Tanzania (n = 9). For each pair of radiographs, surgeons determined the mRUST score and provided a rating of confidence that the fractures were healed. Surgeons were recruited by email to participate in the study, which involved completing a 20-minute online survey. Data from surgeons’ assessments of radiographs and from quality-of-life surveys were then used to assess the reliability and validity of mRUST. Informed consent was obtained from all surgeons prior to their participation in the study, and the study was approved by the IRB at UCSF. The UCSF IRB # is 14-14792, PI is Dr. Saam Morshed. This repository of images from patients with fractures was selected because of the standardization and intervals of acquisition for the parent trial, and the great variance of open [versus closed] fracture healing expected at any given time of follow-up. Patients had been treated with either external fixation (n = 14) or intramedullary nailing (n = 11). For each patient, AP and lateral radiographs and quality-of-life surveys were acquired at 4 time points postfracture . Radiographs were included in the study based on the availability of complete data and high-quality radiographs for each patient at all 4 time points postfracture. Seventy-three patients in the study had received both AP and lateral radiographs at each time point. A picture of each radiograph was taken and uploaded electronically for evaluation. All radiographs associated with these patients were then evaluated by a 4th-year orthopaedic surgery resident (HJR) for image quality. The quality of each image was assessed as “Good,” “Poor,” or “Obstructed,” indicating that the view of the fracture was obstructed . Data was excluded from 48 patients whose radiographic images were assessed as “Poor” or “Obstructed” at 1 or more time points. Twenty-five patients were included who had high-quality radiographs available at all 4 time points, yielding a total of 100 pairs of AP and lateral radiographs.Surgeons evaluated 100 pairs of AP and lateral radiographs of 25 patients with Gustilo-Anderson type I-IIIA open tibial shaft fractures who had participated in a recent randomized control trial in Dar es Salaam, Tanzania.The online survey was designed and presented using Qualtrics survey software . After a live tutorial on mRUST scoring, each surgeon viewed a randomly selected subset of 25 pairs of AP and lateral radiographs, presented in random order. Each pair of images was displayed on a separate page of the survey. For each pair of radiographs, surgeons were asked to evaluate the fracture with the mRUST score and estimates of confidence that fractures were healed. For mRUST scoring, surgeons rated each cortex of the fracture as “no callus,” “callus present,” “bridging callus,” or “remodeled,” with each respective choice receiving an associated score of 1–4. Aggregation of scores for the 4 cortices yielded a total mRUST score for each fracture ranging from 4 to 16. Healing confidence was evaluated by asking surgeons to rate their confidence, on an incremental scale from 1 to 10, that the fracture was “not healed” (lower anchor) or “healed” (upper anchor).–11 at each of the 4 time points postfracture. Patients rated 5 dimensions of their health on 3-level scales , as well as their overall health status using a 100-point visual analogue scale. An overall index score was then calculated for each patient and time point using the “eq5d” package in R. Scores were adjusted for country using the package's built-in parameters for Zimbabwe, since no parameters are currently available for Tanzania in the package.Patients in the randomized control trial completed EQ-5D-3L quality-of-life surveys which estimates ICCs and confidence intervals using the variance components from a one-way ANOVA while accounting for intra-rater and intra-patient measurement groupings. Results of ICC calculations were interpreted based on the work of Landis and Koch and following the example of Litrenta et al. ICC values below 0.2 were defined as “slight agreement,” 0.21–0.40 as “fair agreement,” 0.41–0.60 as “moderate agreement,” 0.61–0.8 as “substantial agreement,” and values above 0.81 as “nearly perfect agreement.”,15 Validity of mRUST was evaluated using linear regression models to determine the correlation between mRUST scores and patients’ quality of life (EQ-5D index) scores and surgeons’ evaluations of healing status at each time point postfracture.Inter-rater reliability was assessed using intraclass correlation coefficients (ICCs) of mRUST scores. ICCs were calculated using the “ICC” package in R,3Results of mRUST reliability analyses, stratified by country and treatment type, are displayed in Tables P = .014, r2adj = 0.280) and 1 year  postfracture. However, no significant correlations were found between mRUST scores and EQ-5D index scores at 6 weeks and 3 months postfracture.Table Correlations between mRUST scores and surgeons’ reported confidence of fracture healing are displayed in Table 4 both overall and within each subgroup of North American and Tanzanian orthopaedic trauma surgeons. Reliability was higher for fractures treated with external fixation compared to those treated with intramedullary nailing. In terms of validity, mRUST scores at later time points (6 months and 1 year) postfracture were significantly associated with patients’ self-reported general health (EQ-5D index scores). Finally, mRUST scores correlated significantly with surgeons’ estimated confidence that a fracture had healed at all 4 time points postfracture.While the mRUST scoring system has previously been validated in the North American context, this study is the first to evaluate the reliability and validity of mRUST in surgeons and patients from under-resourced countries. In the present analysis, inter-rater reliability values fell within the range of “substantial” agreement, according to the criteria outlined by Landis and Koch,,15,16 The present results build on this prior research. Mitchell et al and Litrenta et al identified overall ICC values of 0.71 and 0.68, respectively, for mRUST scoring of lower extremity fractures by North American trauma surgeons. By comparison, the overall ICC value of 0.64 identified here suggests that the reliability of mRUST scoring is relatively stable for surgeons operating in vastly different cultural contexts. However, inter-rater reliability was slightly higher within each subgroup of North American and Tanzanian surgeons than for the overall group of raters, which hints at possible differences across medical institutions and cultures in how surgeons applied the mRUST scoring technique for this study.The reliability of mRUST has previously been validated among North American surgeons and patients. found greater reliability in mRUST score distributions for distal femur fractures treated with intramedullary nailing (ICC = 0.74) compared with those treated with plate fixation (ICC = 0.59). Mitchell et al also found that tibial fractures treated with intramedullary nailing were associated with more reliable mRUST score distributions (ICC = 0.75) than those treated with external fixation (ICC = 0.62). By comparison, the results of our study indicate that mRUST scores were more reliable for fractures treated with external fixation (ICC = 0.72) compared with intramedullary nailing (ICC = 0.57). This discrepancy in findings, while unexpected, may be due in part to differential effects of image exposure levels on the visibility of radiographs depicting fractures treated by intramedullary nailing versus external fixation.Several previous studies have also investigated the reliability of mRUST across different treatment modalities. Litrenta et alCompared to reliability measures, validity measures of mRUST have received relatively less attention in the literature. Here, construct validity of mRUST was assessed by comparing average mRUST scores for a given patient and time point with health-related quality of life as assessed by the EQ-5D score at the same time point. The EQ-5D index score is a relevant clinical outcome measure designed to assess a patient's self-reported health and wellness at various points in the recovery process. The direct link that we discovered between a reasonably “objective” clinical tool (mRUST) and self-reported patient health at 6 months and 1 year postfracture is compelling evidence of construct validity because there is currently no gold standard method of assessing the healing status of open tibial fractures. However, we also found that mRUST scores were not significantly associated with EQ-5D index scores at earlier time points (6 weeks and 3 months). This negative finding may stem from the fact that many tibial fractures, and particularly those that are open, may take more than 3 months to show radiographic signs of healing. Meanwhile, quality-of-life measures at earlier time points may depend less on fracture stability than other factors such as wound healing or regaining range of motion.Another important finding of this study was that mRUST scores correlated significantly with surgeons’ estimated confidence that a fracture had healed at all 4 time points postfracture. These data support the content or face validity of the instrument. Furthermore, mRUST scores explained an incrementally greater proportion of variance in “healed” confidence ratings at each successive time point postfracture, suggesting a stronger association between these 2 methods of assessment of union at later time points. The confidence intervals displayed in Table This study had several important limitations. First, the radiographs available in our database were of varying quality (compared with North American standards), which could have affected the consistency of mRUST scores. We addressed this shortcoming by having an orthopaedic surgery resident (HJR) exclude poor-quality images and those in which the view of the fracture was obstructed. While this method resulted in greater consistency in image quality across the stimuli, it could have introduced some degree of selection bias into our findings. Another important limitation was that many of the surgeons who evaluated the radiographs had limited prior familiarity with the mRUST scoring method beyond the brief training that was administered at the start of each survey. This limitation could have yielded lower reliability scores than might be expected if the study were administered to surgeons with more prior training in the mRUST scoring method. Finally, our sample size was limited by the number of patients (25) who received complete radiographs at all 4 time points postfracture, due to loss to follow-up.In conclusion, this was the first study to validate the mRUST scoring method outside of the North American context. While no “gold standard” exists for evaluating the radiographic healing status of tibial fractures, our findings suggest that mRUST is reliable in diverse clinical contexts and aligns closely with patient-relevant clinical outcomes, particularly at later stages in the healing process. This work paves the way for further research into mRUST and other tools that can improve surgeons’ assessments of fracture healing in diverse and international clinical contexts.