TA15 Ti-alloy is widely used to form key load-bearing components in the aerospace field, where excellent service performance is needed. Near-β forging technology provides an attractive way to form these complicated Ti-alloy components but subsequent heat treatment has a great impact on the final microstructure and mechanical properties. Therefore evaluation and determination of the heat treatment route is of particular significance. In this paper, for the near-β forged TA15 alloy, the formation and evolution of microstructures under different subsequent heat treatment routes  were studied and the cooling mode after forging was also considered. Then, the type and characteristics of the obtained microstructures were discussed through quantitative metallographic analysis. The corresponding mechanical properties  and effects of microstructural characteristics were investigated. Finally, for a required microstructure and performance a reasonable heat treatment route was recommended. The work is of importance for the application and development of near-β forging technology. Ti-alloys, such as TA15, have been widely used to form key load-bearing components in the aerospace field, which are typical hard-to-form components due to the complex in shape and hard-to-deform Ti-alloys used . Near-β p), secondary α phase (αs), and transformed β matrix [p [p improves the impact toughness and plasticity within the volume fraction of 20% [p is related to the highest heating and holding temperature in forging or subsequent heat treatment. The secondary αs determines the fracture toughness, creep properties, and fatigue crack propagation behavior [s would improve the tensile strength, creep properties, and fracture toughness [The mechanical properties of Ti-alloy components are determined by the final microstructure, in general which consists of the primary equiaxed α phase , grain boundary Widmanstätten α (αWGB), which nucleated on the formed αGB, and intragranular Widmanstätten α (αWI), which nucleated in the β grains [s are very complex due to a variety of growth behaviors [s is through complicated interplay between the chemical driving force  and the interfacial energy between α and β grain, etc. [s and equiaxed αp, and further to meet the required performance.However the secondary αβ grains ,11. The ehaviors , diverseehaviors . The varin, etc. . Therefop, and thickness of lamellar αs were investigated by changing annealing temperature [For Ti-alloy, the one-step heat treatment , dual or multiple heat treatment routes  after forging were applied ,6,8,9,15perature , holdingperature , and cooperature ,19,20,21Generally, solution and aging, and toughening and strengthening after forging were adopted to obtain a certain kind of microstructure in a near-α or α + β alloy. Meanwhile the functions of each step heat treatment can be performed. In recent years, the dual or multiple heat treatment routes for Ti-alloy were considered by Zhu et al. ,23 and Sp was controlled to about 10% and 15% through near-β forging and increased to about 20% during subsequent heat treatments. A certain number and aspect ratio of lamellar αs originating from the decomposition of the martensite formed during water quenching after forging, were obtained during toughening, and thin Widmanstätten α precipitated from β matrix during strengthening. The toughening temperature is neither too high nor too low in the two-phase field, otherwise the lamellar αs meeting the requirements in the tri-modal microstructure can not be achieved. Sun et al. [s and transformed β matrix, were formed during solution, and the aging was only used to stabilize the microstructure. Therefore the solution temperature must be appropriate, and the aging temperature should be much lower than the recrystallization temperature. However for the TA15 alloy components after near-β forging, it has still not been resolved as to what kind of subsequent heat treatment route should be adopted.By considering the nearing-β forging before subsequent heat treatments, Zhou et al.  obtainedn et al.  also gotp was mainly determined by near-β forging in these methods [s depend on the whole hot processing . In addition to the grain boundaries, intracrystalline places with high-energy defects  caused by deformation provide the possible nucleation sites for αs, which affect not only the nucleation rate of αs, but also atomic migration [s. Thus, revealing the formation and evolution of primary equiaxed αp and secondary αs under combined action of near-β forging and subsequent heat treat routes is the first problem to be solved.Although the volume fraction of equiaxed α methods ,25, its igration ,27. The In this paper, for the near-β forged TA15 alloy, the microstructure evolution under different heat treatment routes  was studied, then the difference in microstructure and the corresponding mechanical properties were discussed. The work is of importance for determination of a reasonable heat treatment route matched with near-β forging.p in microstructure) equiaxed αp, with an average diameter of 11 μm (average length of lines passing through the centroid of αp per 2 degrees), and residual transformed β matrix, as shown in The TA15 Ti-alloy used in the experiments was from Western Superconducting Technologies Inc. . The chemical composition of the as-received material with a β transus temperature of 980–985 °C is listed in −1 was selected and the reduction of height was 40%, 60%, or 65%. After the forging, three kinds of cooling methods were adopted, air cooling (AC), water quenching (WQ), and a short time of AC combined with WQ , which was used to consider the temperature drop during forging transfer—the forgings were transferred from press to water tank for quenching. Three kinds of subsequent heat treatment routes, annealing , solution and aging (SA), and toughening and strengthening (TS) were considered; a detailed experiment scheme is given in Before near-β forging, the specimens were heated to 970 °C at a heating rate of 5 °C/s and held to obtain a homogeneous microstructure with a holding time of 5 min/mm in diameter. According to the actual forging production, a strain rate of 0.1 sAfter the experiment for the specimens the metallographic observation was implemented by an optical microscope  and quantitative metallographic analysis was carried out using an Image-Pro Plus 6.0 image analysis system . Meanwhile the typical mechanical properties required by aeronautic forgings, such as room and high temperature tensile properties, impact toughness, and fracture toughness, were measured according to the industry standards—“Metal test method”, HB5143-80, HB5195-81, HB5144-80, HB5142-80 , respect−1/65%) and cooled by different modes  resulted in martensite transformation and the reservation of the distortion energy and defects caused by forging. Air cooled for a short time and then water quenched after near-β forging, the microstructure, which is shown in p, grain boundary α (αGB), grain boundary Widmanstätten α (αWGB), intragranular Widmanstätten α (αWI) and residual martensite. β→α phase transformation occurred at a low cooling rate, and the precipitated α phase preferred to nucleate at β grain boundaries, then on the formed αGB and defects in β grains [WGB within the same or different β grains can be observed in GB and αWGB [W (αWGB and αWI) with an interlaced distribution, a small amount of equiaxed αp and residual β, and very few αGB. Since there existed lots of defects in the β grains after forging, the αWI was the main component of secondary αs in nt modes b–d. The β grains . Only paand αWGB . When aiGB or static recrystallization of αp [W appeared, as shown in W preferentially nucleated and grew on the existing αGB due to a low supercooling degree [W during air cooling after forging. When annealed, some formed αW (little ones) dissolved, while some grew both in length and width direction during heating and holding. In succedent AC, the existing αW thickened a bit, and it already had lots of α phase (αW and αp) which consumed a large amount of α-stablized elements, hence only seldom αW was formed. Short and thin disordered αW presented in W in subsequent heat treatment [W [W precipitated both on formed αGB (αWGB) and inside β grains (αWI) in a disordered manner during subsequent annealing.The optical micrographs of TA15 alloy after near-β forging (AC or WQ) and subsequent low-temperature annealing (LTA) (830 °C/1 h/AC) are exhibited in on of αp . When aig degree , meanwhireatment . Moreovetment [W . As a re−1/65%/WQ) specimen, the typical tri-modal microstructure was obtained  and in β grains simultaneously and grew rapidly. As holding time was prolonged, some thin αs dissolved and others thickened through merging [s thickened further, and tertiary lamellar αs precipitated from β to form the transformed β matrix.obtained a after S merging . In subsp, scattered thick lamellar αs, and very thin tertiary αWI, was obtained after near-β forging  and SA treatment, as shown in s, which originated from the decomposition of the martensite, was insufficient because it was consumed partially during the short time of AC after forging, and the formed αs thickened and lengthened. For equiaxed αp, on one hand the growth of already-nucleated grains, meta-dynamic and static recrystallization of αp occurred and resulted in very small α, as marked by red ellipses in p coarsened through the Ostwald ripening effect or attached-growth of α phase , the martensite decomposed to form αs and β phase. Some scattered thin interlaced tertiary αW formed through β→α phase transformation during air cooling [p were restrained. During the subsequent strengthening process, due to a relative low temperature (800 °C) the driving force for the equiaxed αp coarsening was insufficient, which resulted in small equiaxed αp.tructure a. Compartructure a, more s cooling . Due to −1/60%/(AC + WQ) + 950 °C/1 h/WQ + 800 °C/5 h/AC. Compared with that in s were obtained but a large amount of thin tertiary Widmanstätten αW appeared. Meanwhile the equiaxed αp was coarse. The main reason was that short AC before WQ after forging changed the formation stage and source of lamellar αs. For near-β forged (AC + WQ) specimen, the final lamellar αs came from the residual Widmanstätten αW formed during AC and decomposition of residual martensite during high temperature toughening, but for near-β forged (WQ) specimen, it only came from the decomposition of martensite.−1/65%/AC + 970 °C/1.5 h/WQ + 850 °C/1.5 h/AC , about 20% equiaxed αp and a large amount of Widmanstätten αW appeared , the Widmanstätten αW nucleated on β GBs and α/β interface preferentially and grew into a clustered morphology. Meanwhile for martensite the massive transformation, which may have been caused by the composition inhomogeneity of the material, occurred as marked by the blue ellipse in When the toughening temperature was equal or higher than the forging temperature, an interesting phenomenon was discovered. For TA15 alloy after 965 °C/0.1 s1.5 h/AC c, a bimoribution c. The reappeared d. Held aBased on the analysis above, for the near-β forged TA15 alloy after the heat treatment routes involved, three types of microstructures were obtained, which were bimodal c, quasi-p changed between 18.2% and 21.6%, and average grain size (diameter) between 6.26 and 7.20 μm . For type A3  combined with SA  or HTA , consist–1.15 μm .p (6.20–6.40 μm) and 46.2%–47.8% thick lamellar αs (1.20–1.35 μm) (s appeared but for type C1 (near-β forging/WQ + SA) αs was thicker (1.33 μm) and longer (p was large (8.98 μm) and there were about 15.2% moderately thick lamellar αs  and SA , and aft1.35 μm) . For micd longer . For typellar αs , but a lmR = 1000.0–1040.0 MPa, pR0.2 = 910.0–960.0 MPa) and plasticity . As shown in mR = 1098.0 MPa, pR0.2 = 1049.0 MPa). G. Lutjering [s, the effective slip length decrease to the width of a single lamellae plate, which is benefit for the properties aforementioned. Meanwhile ductility is improved with the increase of equiaxed αp content within 20% [p (14.5%), therefore, it possessed the lowest plasticity . Research showed that equiaxed αp contents above 20% contributed little to the increase of ductility, but had detrimental effects on other performances [mR = 981.3 MPa, pR0.2 = 822.0 MPa) but the highest elongation (A = 23%). Quasi tri-modal microstructure of type B  but the highest percentage reduction of area (Z = 53%). On the one hand disordered lamellar αs contained in this kind of microstructure is good for the decrease of the α colony size, on the other hand a large amount of transformed β matrix increase the effective slip length. The interactions of these two effects led to the lowest room-temperature strength.Bimodal microstructures of types A1–A4 possessed moderate room-temperature tensile strength  but type C2 possessed a low impact toughness (aku = 45.0 J·cm−2). Microstructures of type B possessed the highest fracture toughness (K1C = 101.3 MPa·m1/2) but low impact toughness (aku = 49.0 J·cm−2). Types A1–A4 had moderate fracture toughness (K1C = 80.8–85.5 MPa·m1/2) and impact toughness (aku = 55.4–60.0 J·cm−2). This is because the fracture toughness increased with the increase of the effective slip length [As shown in p length .W in the microstructure  and near-β toughening + strengthening (NTS), bimodal microstructures were obtained, which possessed moderated comprehensive properties , types A2–A4 in tructure b, which tructure .For near-β forged (WQ) specimen the subsequent SA treatment could result in a tri-modal microstructure a and excWhen the near-β forged specimen was air cooled for a short time and then water quenched, the subsequent SA resulted in a quasi tri-modal microstructure b and higFor near-β forged (WQ) specimen subsequent TS treatment could also result in a tri-modal microstructure a and a s(1)W, while water quenching led to thin (0.45 μm) interlaced αW.Bimodal microstructure, possessing moderate low and high temperature tensile properties, fracture and impact toughness, was obtained through near-β forging combined with low-temperature annealing (830 °C/1 h/AC) or near-β toughening and strengthening treatment (970 °C/1.5 h/WQ + 850 °C/1.5 h/AC). Air cooling after near-β forging resulted in thicker (0.75 μm) clustered α(2)After near-β forging (AC + WQ) combined with solution + aging (930 °C/1 h/AC + 550 °C/5 h/AC) or high-temperature annealing (930 °C/1 h/AC), a quasi tri-modal microstructure with low room and high temperature tensile strength and impact toughness but high fracture toughness was obtained.(3)p (6.20–6.40 μm) and thick lamellar αs (1.20–1.35 μm), possessing good comprehensive performance matching.A tri-modal microstructure was obtained after near-β forging (WQ) and solution + aging (930 °C/1 h/AC + 550 °C/5 h/AC), or after near-β forging (WQ) and toughening + strengthening (950 °C/100 min/WQ + 800 °C/8 h/AC), consisting of small equiaxed α(4)For near-β forged TA15 alloy, when moderate mechanical properties were required, water quenching after near-β forging and subsequent low-temperature annealing were recommended; when excellent comprehensive performance was needed, solution and aging treatment was recommended; and when high fracture toughness was considered, high-temperature annealing treatment was recommended.


This study aimed to explore the neuro-cognitive deficits of alcohol-induced psychotic disorder as compared to the cognitive deficits of uncomplicated alcohol dependence.Participants were recruited from the acute psychiatric admission wards of the Department of Psychiatry, University of Stellenbosch and Stikland and Tygerberg Academic Hospitals in the Western-Cape, South Africa. Participants who met DSM IV TR criteria (American Psychiatric Association. Diagnostic and statistical manual of mental disorders. American Psychiatric Association, Washington, DC, The groups were matched demographically with similar period of abstinence prior to assessment. The alcohol-induced psychotic disorder group experienced first psychotic symptoms at age 35. The results reflected statistically significant differences on tasks measuring immediate memory; recall upon delay; exaggeration of memory difficulty and abstract thinking.This study concurs with earlier literature that some cognitive deficits are greater in alcohol-induced psychotic disorder compared to uncomplicated alcohol dependence. The understanding of alcohol-induced psychotic disorder (AIPD) as an illness phenomenon is becoming is increasingly important for the clinician. AIPD is often described as a “rare complication”  of alcohRecent research , 6 concuThere are inconsistent reports regarding the outcome of this disorder , 5. SomeThe age of onset of alcoholism reported in AIPD varied between 21.4  with theAlthough a number of reports , 14, 15 The present introductory study compared the neuropsychological functioning of patients who were diagnosed with AIPD with the neuropsychological functioning of alcohol dependent patients in order to differentiate between these two conditions from a neuropsychological perspective. Additionally, this paper aims to expose the associated brain region which is potentially at the genesis of AIPD. Understanding the underlying pathophysiology may lead to more effective treatment of AIPD and prevent relapse, including recurrent re-admissions and possibly the development of more severe pathology.The susceptibility to acquire neuropsychological deficits resulting from alcohol use or abuse is multifactorial . In addiAlcohol misuse may cause diffuse brain damage therefore most domains of neuropsychological assessment may be affected . Even alVocabulary is usually not affected by alcohol abuse , 23, butAlcohol abuse is often detrimental to memory function , 25, 26.A number of authors , 23, 26 Neuropsychological deficits of uncomplicated alcohol use disorders include mild cognitive deficits in executive functions . SpecifiAlthough numerous studies elaborated on the complexity and diversity of the neuro-cognitive fall-out associated with alcohol use, there has been very little focus on AIPD. Earlier reports by Bleuler 1916  generallThis introductory study formed part of a larger study aimed at differentiating alcohol-induced psychotic disorder (AIPD) from uncomplicated AD and Schizophrenia . In partTwo groups (AIPD and AD) of study participants were recruited. The AIPD group (n = 13) were recruited from the acute psychiatric admission wards of the Department of Psychiatry, University of Stellenbosch and Stikland and Tygerberg Academic Hospitals in the Western-Cape, South Africa. The AD group (n = 16) was recruited from an alcohol rehabilitation unit at Stikland Hospital.Before the neuropsychological assessments were completed, a structured interview using the Mini International Neuropsychiatric Interview (Version 4.4) , 36, wasThe severity of alcohol dependence questionnaire (SADQ) was used to determine the severity of alcohol dependence in both groups , 38. AltWe assessed the severity of psychotic symptoms by applying the positive and negative syndrome scale for schizophrenia (PANSS) , 39 on pNeuropsychological assessments were performed and supervised by two clinical psychologists at either Tygerberg or Stikland Hospital.The following neuropsychological test battery was administered:The Controlled Oral Word Association Task (COWAT) is a measure of verbal fluency through assessing the ability of a person to generate as many words as possible in a minute. Performance on the verbal fluency task involves short term immediate memory, cognitive flexibility, and initiation .The Trail Making Test (TMT) A and B provides information regarding visual scanning, speed of hand eye co-ordination and information processing. The TMT B assessed the ability to alternate between different sets of stimuli (shifting) and is useful in detecting executive and cerebral dysfunction , mental Rey Auditory Verbal Learning Test (RAVLT) trails I–V and the delayed recall was administered to assess verbal memory and learning .Visual reproduction (VR) Trails I and II involves a ten second exposure to a shape, followed by immediate response. This test is considered sensitive to right hemisphere injury .Rey Complex Figure-Copy measures visuospatial constructional ability and visual memory for complex visual stimuli . It demoRey 15 Item assesses the participants’ effort when completing a memory task and the extent to which memory problems are exaggerated , 43.Similarities subtest of the South African Weschler Adult Intelligence Scale (Sim-SAWAIS) gauges abstract thinking by asking the patient to describe similarities between objects .The Clock Drawing Test (CDT) evaluates visuospatial and constructional abilities. The clock is drawn on a blank sheet; the time on the clock should reflect 10 past 11 and the test is scored out of 10 .The two groups (AD and AIPD) were compared with respect to the continuous variables by using pooled T tests, or equivalently ANOVA. The variances of the variable Rey Fifteen Item Test (RFIT) differed between the two groups, so this T test was done by using the Satterthwaite  approachEthical approval was obtained from the Committee for Human Research of the Faculty of Health Sciences at the University of Stellenbosch. Permission to conduct the study was obtained from the relevant Hospital authorities. All participants gave informed consent to participate in the study prior to the start thereof. Due consideration was given to the privacy, confidentiality and anonymity of the participants. The research was conducted in accordance with the prescripts of the declaration of Helsinki .Table Upon initial ANOVA, the AD group had a statistically significant higher level of education (HLOE) than the AIPD group. Upon further comparative analysis with HLOE as a covariate, HLOE did not influence the findings. Even though the AD group reported more severe alcohol dependence than the AIPD group (SADQ), the difference did not reach statistical significance.Patients with AIPD presented mainly with auditory hallucinations, delusions (with predominant persecutory themes) and anxiety in the presence of a clear consciousness. The mean scores on the PANSS scales were: 20.1 , 16.7 , 37.5  and 74.3 .Table This study demonstrated statistically significant deficit in immediate verbal memory, increased effort when completing a memory task and impaired abstract verbal reasoning skills in patients with AIPD when compared to patients with uncomplicated AD. Memory, specifically explicit memory, short term memory and learning, may be impaired by the chronic use of alcohol. Our results do not support the observations of Bleuler  of intacBoth groups performed above the cut-off score on the task measuring effort when completing a memory task and the extent to which memory problems are exaggerated which lends further support for more severe memory difficulties in the AIPD group compared to the AD group. On delayed verbal recall, the AIPD group performed in the below average range, while the AD group performed within the average range but the difference did not reach statistical significance. Delayed verbal recall, as measured by the RAVLT, refers to recall of words after a 2–45 min delay . ImpaireWith reference to impairment on the task assessing abstract verbal reasoning skills, in the AIPD group, the similarities subtest is reportedly sensitive to cognitive pathology that affect verbal abstraction which is connected to left temporal and frontal involvement . This maThe findings concur with previously reported research suggesting cognitive impairments such as difficulty with attention and concentration are found in AIPD , 24. TheBoth groups demonstrated ability for new learning with a positive, but fluctuating learning curve. New learning for the AIPD group fell within the below average range while new learning for the AD group was marginally better and was in the average range but the difference also did not reach statistical significance.On tasks assessing visual memory (immediate and delayed), both groups scored within the average range with the AD group’s score better but again no statistically significant difference recorded. In terms of visuospatial assessment, both groups demonstrated average ability.It is interesting that the AIPD group’s average of reported drinking severity (SADQ) was lower than that of the AD group. However, this may be misleading as it could be explained by recall bias in the AIPD group due to greater memory impairment, associated impairment of insight or to deliberate under reporting .The study has a number of limitations. It is a cross-sectional study with a small number of participants. The participants were selected from two different clinical populations within one institution. The AD group was selected from a program that requires a certain level of education which increased the possibility of selection bias. The scope of neuropsychological exploration needs to be expanded to include all the major neuropsychological domains, such as attention and concentration, all aspects of visual and verbal memory, speech and language functioning, motor control and all aspects of executive functions. Furthermore, a detailed analysis of predisposing factors needs to be performed to rule out their association with the cognitive deficits. It therefore remains to be determined to what extent the cognitive deficits in AIPD demonstrated in this study suggests pre-existing vulnerability rather than primary effect of alcohol. These limitations, together with the fact that we did not correct for multiple comparisons, mean that our results should be regarded as preliminary.In conclusion, this study concurs with an earlier  that som


The participants viewed a video with discharge instructions on MTBI and filled out a questionnaire that measured their attitude towards the use of a video as part of discharge instructions.The objective of this study was to determine the attitude of patients, healthcare professionals, and noninjured lay persons towards adding a video with discharge instructions to patient care for patients with mild traumatic brain injury (MTBI). A survey was conducted at the emergency department (ED). Participants consisted of MTBI patients  and 70% of the noninjured lay persons considered the video to be a valuable addition to oral discharge instructions. For 84% of patients, verbal information from the doctor is of importance. And, 50% of patients would like to receive additional video discharge instructions.The majority of noninjured lay persons and healthcare professionals and half of the MTBI patients consider a video with discharge instructions to be a valuable addition to patient care. Video discharge instructions are a relative low-cost measure that could enhance patient care at the ED, provided that this does not compromise the personal contact between patient and healthcare professional. Mild traumatic brain injury (MTBI), or concussion, often leads to persistent symptoms. These symptoms, such as headaches, mild cognitive problems, and dizziness, may last for weeks or even months after the concussion –3.Evidence suggests that providing patients with discharge instructions containing adequate educational information on MTBI can help reduce or even prevent post-concussion symptoms, particularly early after the injury . PatientAn important step in finding the most effective way of providing patient information on MTBI is to assess the feasibility and acceptability of an online video with discharge instructions.The objective of this study was to determine the attitude of patients, healthcare professionals, and noninjured lay persons towards adding a video with discharge instructions to patient care for patients with MTBI.A survey study was conducted at the ED of a tertiary center in Rotterdam, the Netherlands, between November 2014 and July 2015. The aim was to include 50 MTBI patients, 50 healthcare professionals, and 50 noninjured lay persons. The study subjects consisted of a convenience sample of MTBI patients, healthcare professionals, and noninjured lay persons. The noninjured lay persons were recruited from a social network by contacting them personally or by email. Snowball sampling was used for the recruitment strategy, i.e., participants were asked to recruit future participants among their contacts. The selection criterion was that the noninjured lay persons were not engaged in any medical profession. The healthcare professionals consisted of nurses and doctors. Selection criteria for the healthcare professionals were that they had to be entrusted with the care for MTBI patients and were not involved in the study. Healthcare professionals were recruited during their shift at the ED or the neurology department. The selection criteria for MTBI patients were treatment at the ED, aged 18 years and older, a Glasgow Coma Scale  greater than 13 at first contact, and post-traumatic loss of consciousness of less than 30 min (indicated in the history of the patients). MTBI patients were excluded if they did not master the Dutch language, had an intracranial abnormality on the CT-scan, a focal neurological deficit, or if they were unable to give informed consent. Patients were recruited by one of the researchers according to a rotating schedule representing all shifts and days of the week.https://drive.google.com/file/d/0B90l2el_JbUtVlhWdk1TM3ltdkE/edit?usp=sharing). The information in this video is based on the national guideline for management of mild head injury which includes advisory information for patients. The discharge instructions shown in the video provided background information on MTBI, information about common symptoms, typical course of recovery, advice about how to manage or cope with symptoms, gradual reintegration to regular activities, and when to contact a medical expert. Healthcare professionals and noninjured lay persons either watched the video on a research computer  or at home through the online link. Hereafter the healthcare professionals and noninjured lay persons filled out the questionnaire individually, on paper, or digitally. Patients watched the video at the ED after their treatment was finished, before discharge from the ED when they had a GCS of 15. They filled out the questionnaire immediately after watching, at the ED. The questionnaire administered to the MTBI patients and noninjured lay persons which was developed in agreement with a psychologist and an emergency physician, consisted of questions on age, sex, and educational level (high education level: finished at least higher secondary education) and nine questions concerning the video and their attitude towards the applicability and value of the use of adding the video with discharge instructions to patient care. The questionnaire administered to the healthcare professionals consisted of questions on age, sex, position, and 11 questions on the video and their attitude towards the applicability and value of the use of adding the video with discharge instructions to patient care. The questionnaire also included open ended questions which asked the participants to explain their answer. Ethical approval was obtained from the research ethics committee of the study center before the initiation of the study (MEC-2015-175). All MTBI patients gave written informed consent before inclusion.Once participants decided to participate in the study, they were shown a video with discharge instructions for MTBI  in statistical package for social sciences (SPSS) 21.0.n = 31) would like to receive additional written, telephone, or video discharge instructions 68.0% (n = 34) stated that they would watch the video at home. Half of the patients  indicated that they preferred the video to be part of their discharge instructions  were willing to participate in the study. The median age of the MTBI patients was 46.5 years range: 18–93] (Table 8–93 (Tabn = 47) considered the video to be a valuable addition to their discharge instructions and all would advise patients to watch the video  was in favor of giving patients the link to the online video so they can watch the video at home. No statistically significant difference was found in preference for video discharge instructions for gender or age of the healthcare professionals.Fifty healthcare professionals participated in the study. The median age was 30.5 years [range 23–61] (Table n = 35) considered the video to be a valuable part of discharge instructions .Fifty noninjured lay persons were included with a median age of 48.0 years range 21–87] (Table –87 (TablThis study showed that the majority of healthcare professionals and noninjured lay persons consider a video with discharge instructions to be a valuable addition to patient care.Half of the of MTBI patients believed that a video could be a valuable part of their discharge instructions. Our study showed that 84% of the patients indicated that they wanted to receive oral discharge instructions, with or without additional alternative methods. We speculate that the main reason for not wanting a video may be that they place high value on personal contact with medical professionals.Remarkable is that compared to other studies, we found less patients would be content with the video as part of their discharge instructions . An impoA necessary condition for offering online video with diagnosis-specific discharge instructions is internet access among the target group. In the Netherlands, 97% of the inhabitants have internet access [Important to note is that the video used in this study showed a doctor explaining MTBI and the consequences and some parts included written text, but the video did not contain animations. This may have affected our results. A recent study concluded that spoken animations may be the best way to explain complex health information to people with low health literacy . Hence, The majority of noninjured lay persons and healthcare professionals, and half of the MTBI patients consider a video with discharge instructions to be a valuable addition to patient care. Video discharge instructions are a relative low-cost measure that could enhance patient care at the ED, provided that this does not compromise the personal contact between patient and healthcare professional.From a professional perspective, video discharge instructions could enhance patient care at the ED, but this should be embedded in counseling approaches tailored to different preferences of patients.


Australia has a maternal mortality ratio of 6.8/100000 live births, a rate akin to other developed countries and consistent with the high level care provided within the Australian health care system. With maternal mortality at very low levels assessment of severe maternal morbidity is increasingly being used as an indicator of quality of care and to identify areas for improvement in maternity services. The WHO maternal ‘near miss’ criteria is a standardised tool has been increasingly used worldwide to assess maternal morbidity and standards of maternity care. The aim of this study was to determine the rate and aetiology of maternal ‘near misses’ at King Edward Memorial Hospital (KEMH) using the WHO near miss criteria.Cases of maternal ‘near miss’ were prospectively identified at KEMH using the WHO near miss criteria over a period of 6 months (1st December 2014 to 31st May 2015). A descriptive analysis of the results was undertaken.During the study there were 2773 live births with 19 women who had ‘near miss’ presentations. There were no maternal deaths. The maternal ‘near miss’ index rate was 7/1000 live births. The main causes of obstetric ‘near miss’ were obstetric haemorrhage, pre-eclampsia and early pregnancy complications.The rate of maternal ‘near miss’ at KEMH was 7/1000 live births and post-partum haemorrhage was identified as the most common aetiology, consistent with other studies in developed countries. Further research comparing currently utilised local, state and national morbidity systems would allow further validation of the WHO near miss criteria in Australian settings.The study presented in this publication was undertaken at King Edward Memorial Hospital, 374 Bagot Rd., Subiaco WA 6008.The online version of this article (10.1186/s12884-018-1862-6) contains supplementary material, which is available to authorized users. Maternal mortality in Australia has decreased significantly over the last century, from 41.2 per 100,000 women giving birth in 1964–1966 period, to 7.1 per 100,000 women in the years 2008–2012 [One of the mainstays of addressing deficiencies of maternal care in the health system has been a maternal death audit both at the level of the facility and also nationally through confidential enquiries of maternal deaths . These hMaternal near miss and maternal deaths share many characteristics and pathological processes . MoreoveIn 2009 the WHO published near miss criteria to provide a standardised approach to identify near miss in both individual institutions and larger health care systems . The subThe aim of this study was the application of the WHO near miss criteria and to assess its utility in identifying cases of severe maternal morbidity in a developed tertiary hospital setting.maternity hospital, is located in Perth, Western Australia (WA). It provides pregnancy and neonatal care within the greater Perth Metropolitan area and is the main referral centre for complex, tertiary maternity care for the state population of 2.6 million people [King Edward Memorial Hospital for Women (KEMH), Western Australia’s largest n people , which iAmong the clinical audit sytems in use at KEMH is the Clinical Incidence Monitoring System (CIMS), a hospital database incorporating reporting of clinical cases where adverse maternal outcomes or deviations of care from standard protocol occur. CIMS reporting is strongly encouraged but is not mandatory. Any health professional can place a clinical incident into the system, and is then presented to the appropriate clinical incident review expert panel committee at KEMH Some of these cases relate to severe life threatening scenarios, but also include less life threatening morbidity such as 4th degree tears or deviations from standard practice of care e.g. caesarean section for a second twin.This prospective observational study included all maternal ‘near misses’ and deaths at KEMH between 1st Dec 2014 and 31 May 2015. During this period, all women admitted to KEMH during pregnancy or within 42 days of its termination were eligible for inclusion. A form consisting of clinical and biochemical parameters indicative of severe obstetric morbidity was broadened to include specific disease entities and interventions, thus allowing easy identification of potential ‘near miss’ cases  was calculated by the number of maternal near-miss cases per 1000 live births . PrimaryDuring the 6-month study period there were 2773 live births: 19 cases of near miss and no maternal deaths. The MNMR was 7/1000. Three cases required transfer to Intensive Care Unit of a nearby general tertiary hospital while all the rest were managed within the setting of the High Dependency Unit (HDU) at KEMH.Most cases of severe maternal outcome were from direct causes with the most common aetiology being postpartum haemorrhage, pre-eclampsia and early pregnancy complications Table . IndirecThe mean age of the near miss case was 29, while the median parity was 1. The majority (14 women) were residing in metropolitan areas while 5 women came from rural or remote locations. The mean age of the background cohort was 30, while the median parity was 1. 14.6% of women admitted to KEMH were from rural and regional areas during the 2014/2015 year.Near miss cases were more common in the third trimester with 67% of cases. Complications during the first and second trimester accounted for 22 and 11% of cases respectively.The ‘near miss’ rate of 7 per 1000 live-births was consistent with other studies on severe maternal morbidity in Australia and in developed countries internationally –18. AustMaternal near miss: mortality ratio (MNM:MR) and MMR were not able to be calculated for this cohort as no deaths were present in the study. The MNM:MR tends to reflects quality of care within the health facility with a low ratio indicating poorer care with large number of near miss cases progressing onto maternal deaths. Near miss studies undertaken in developing countries in the region have highlighted this, though consideration must also be given to the late presentation of such patients where limited care can only be provided to those in such moribund states. The last death at KEMH was more than 7 years ago, reflecting the rarity of maternal mortality in an individual obstetric unit in a well-resourced setting.Unsurprisingly, all cases of severe Obstetric morbidity received critical care support consistent with the capacity of tertiary maternity hospitals in well-resourced settings. Studies in Cairns and Darwin also showed high levels of critical care admission/support well above the 70% recommended by the WHO , 7, 11.This audit found that post-partum haemorrhage (PPH), pre-eclampsia and early pregnancy complications (ectopic pregnancies and miscarriage) were common contributors to severe morbidity, consistent with national and international surveillance reports , 21, 22.There were many clinical incidents reported during the 6-month study but none of the near misses were Severity Assessment Code 1 (SAC1) cases, which reflect the most severe cases systemic issues leading to adverse outcomes. Our study indicated the CIMS is not geared to singularly identify maternal near miss or severe obstetric morbidity and relies on accurate reporting by staff members which is a significant limitation of voluntary databases. A recent near miss study in Darwin  showed sThe WHO criteria classified five of the cases not fulfilling CIMS criteria as true near misses. The cases were related to criteria of decreased platelets (< 50), use of vasoactive agents and increased respiratory rate. Acute thrombocytopenia is one of the more common laboratory findings meeting criteria for WHO near miss  and as nThis raises the question of whether certain criteria e.g. increased RR and decreased platelets should be incorporated as individual entities in the maternal near miss criterion or rather be utilised as an adjunct to other WHO near miss criteria. Additionally, six cases were included based on the transfusion of more than 5 units of blood. The availability of blood is variable between different settings but there are also differing thresholds among clinicians in the provision of blood transfusion . TherefoThere was a significant effort in attaining cases of potential near miss and then reviewing those cases to identify true WHO near miss criteria. Regular diligent review of clinical areas by the authors and supporting staff was required and as such it is possible, but unlikely that there were cases that were missed. However, it must be emphasised that such a prospective collection requires a significant input of manpower and time. It is hoped that as the WHO ‘near miss’ tool develops and is adapted into practice, software may be developed to automatically identify near misses using routinely collected parameters minimising the error of missing cases.The short audit time also limited the number of cases attained during the study. A longer study period would provide a more accurate trend of near miss at KEMH and allow more robust comparison of the WHO near miss tool to currently utilised morbidity systems in Australia. In particular comparisons of the WHO near miss system to validated tools such as Maternal Morbidity Outcome Indicator (MMOI)  developeA longer audit period would also have facilitated epidemiological analysis of cases with attention to identifying risk factors e.g. age, parity and areas for clinical improvement within the health facility. Our study showed a relatively low parity among our cases with 5 women from rural/regional areas though any meaningful analysis would require larger number of clinical cases. Studies have indicated that age, SES status and rurality among other factors as significant risk factors for morbidity and a larger cohort would allow identification of whether these are apparent , 20.Though review of clinical management of near miss cases was outside the scope of this study, the study of near miss cases provides a unique opportunity to not only objective access institutional care but to understand the circumstances which may have led to the near miss from the perspective of recovered patients and their families.. An in-depth review of a larger cohort of cases may show avenues for clinical improvement and a greater comprehension of issues important to patients experiencing near misses.The WHO near miss rate of 7/1000 at KEMH is consistent with studies in other similar developed economy settings. The WHO near miss criteria was able to identify cases of severe morbidity and may provide a suitable framework for determining cases of maternal near miss in an Australian setting. However, further refinement of the WHO criteria to the Australian context along with comparisons to other morbidity collections systems in Australia is required.Additional file 1:King Edward Memorial Hospital Maternal ‘Near Miss’ collection form. Data collection tool for the collection of maternal near miss cases at KEMH. (DOCX 19 kb).Additional file 2:WHO near miss criteria. WHO near miss criteria is illustrated and divided into 3 main categories: clinical, laboratory and management based criteria. (DOCX 85 kb).


Aims and method The acute psychiatric in-patient service in Christchurch, New Zealand, recently changed from two locked and two unlocked wards to four open wards. This provided the opportunity to evaluate whether shifting to an unlocked environment was associated with higher rates of adverse events, including unauthorised absences, violent incidents and seclusion. We compared long-term adverse event data before and after ward configuration change.Results Rates of unauthorised absences increased by 58% after the change in ward configuration (P = 0.005), but seclusion hours dropped by 53% (P = 0.001). A small increase in violent incidents was recorded but this was not statistically significant.Clinical implications Although unauthorised absences increased, the absence of statistically significant changes for violent incidents and a reduction in seclusion hours suggest that the change to a less restrictive environment may have some positive effects. Other studies are considerably older3 and were largely positive in their findings, with the exception of the study by Molnar et al,4 which reported an increase in the frequency of ‘elopement’ (unauthorised absence) from 2.5 to 7% of admissions in the context of changing ward policy to allow a largely unlocked environment.The locking of psychiatric institutions is an important topic because detention involves significant restrictions on human rights, ensconced in the Universal Declaration of Human Rights. However, studies that have evaluated the impact of unlocking a psychiatric ward are rare; we were only able to identify four such studies spanning 7-decade-long assessing in this area. Lang 5 and emphasises a duty to provide psychiatric care in the least restrictive environment. A desire to provide least restrictive care created the impetus for our local psychiatric service to shift from an acute in-patient environment consisting of two locked wards and two unlocked wards to four largely unlocked wards. It also provided the opportunity to evaluate the impact of the change through reporting of long-term data detailing adverse events, such as unauthorised absences, ward violence and rates of seclusion, prior to and following the changes in ward environment.Any consideration of locked psychiatric wards must be viewed in the context of emerging policy that recommends minimising the use of locked psychiatric wardsData for this study were taken from the acute in-patient service in Christchurch, New Zealand. The service is the sole provider of acute in-patient services to adults aged 18–65 in the city of Christchurch, outlying towns and rural areas, with the exception of forensic patients, patients with an intellectual disability and in-patients requiring planned detoxification from substances, who are admitted elsewhere. The acute in-patient service receives admissions from community and emergency psychiatric services when care in the community is no longer feasible, with a typical case mix consisting of patients with affective disorders, psychotic disorders and personality disorders.The service underwent major architectural change in 2013. Before, the service was configured with two locked wards , two wards  that were predominantly unlocked except overnight, and a seclusion area with 3 seclusion rooms. In response to service development initiatives and the desire to provide less restrictive care, the wards were reconfigured into 4 largely unlocked 16-bed wards (except overnight when the wards remain locked). At the end of each ward is a zone called the ‘high care area’, which is quieter than the general ward and provides care for up to three of the more unwell patients. Each high care area is continuous with its adjacent ward and can be designated ‘high care’ when doors are closed or locked, or be regarded as part of the general ward when extra clinical input is not required. The décor and bedrooms of the high care area are identical to the adjacent ward, but an additional lounge, bathroom and courtyard are provided in order for the high care area to act as a self-sufficient unit when required. All wards, including the high care areas, are intended to be unlocked as much as possible but each ward or high care area can be locked separately in order to detain a patient if this is deemed necessary. The high care area bedrooms were not outfitted for seclusion but the seclusion area remained unaltered and could still be used if required. In addition to these structural changes, nursing staff numbers increased, from 27 nurses routinely rostered on the wards to 34 nurses. However, if a nurse was required to provide one-to-one supervision after the change, this needed to occur within existing staff levels, whereas previously this was not the case. The frequency of one-to-one supervision pre- and post-change was not systematically recorded and is not readily available for review.The acute in-patient service routinely records data on unauthorised absences, seclusions and violent incidents. Unauthorised absences include patients who are under involuntary mental health legislation and leave the ward without permission or fail to return from authorised leave, and voluntary patients who leave the ward outside of their agreed treatment parameters or fail to return from agreed leave. Nursing staff follow procedures when absences occur, including filling out a form documenting the absence which is then collated in a central database.Violent incidents are assessed clinically and categorised into a number of subcategories including verbal abuse, threats of violence and assaults; all are recorded and collated centrally.6 seclusion reduction initiatives became embedded into the routine care environment of the acute in-patient service from 2010 and the goal of reducing seclusion occurred alongside the plan to provide a less restrictive environment through the ward redevelopment. Although seclusion rates are likely to be reduced by the seclusion reduction initiatives, the change in ward environment had the potential to hinder or assist the goal of reducing seclusion. As a consequence, we report seclusion rates which are collated centrally on a database and are therefore available for review.Seclusion is initiated by nursing staff as an intervention of last resort for managing a situation of imminent or actual violence. In response to international and New Zealand initiatives,U-test was used to compare the 18 months prior to the change with the 18 months following the change. The change in ward environment was staggered during June and July 2013; this time period was therefore not included in any data analysis as our goal was to examine a longer-term impact of the policy change as opposed to short-term effects during and following the transition.The AWOL (absent without leave), violent incidents and seclusion databases have all collected data over an extended period. In de-identified form, they provided the opportunity to examine rates of unauthorised absences, seclusions and violent incidents for 18 months prior to the change in ward configuration and compare this to 18 months following the change. The mean rates and standard deviations of the monthly adverse events were calculated for the pre- and post-change 18-month intervals. As the data were non-parametric in nature, the Mann-Whitney We also report frequency and duration of the use of environmental restraint to clarify whether or not the intended change to a largely unlocked environment was successful or resulted in frequent locking of the newly configured wards. The frequency of Safety Assessment Code (SAC) 1 and 2 incidents  involving psychiatric in-patients is also provided pre- and post-change and examined for the possibility of a change in more serious adverse events that would not be detected by previous methods.U-test.Ward occupancy data are routinely collected by means of a census taken at midnight every 24 hours. Admission data to the acute in-patient service and the forensic service are also recorded daily. Forensic in-patients are predominantly admitted from forensic out-patient services, courts and prisons, and not from general out-patient services. However, we examined admission and occupancy data for these services to test for the possibility that changes in outcome data were confounded by variations in occupancy or transfer to the more secure environment of the forensic service. The rate of monthly admissions pre- and post-change was compared using the Mann-Whitney Although this was a study of group data and individual files were not accessed, ethics approval was sought and granted by the local University of Otago ethics committee (reference number HD 14/21).P = 0.005). As some literature suggests unauthorised absences may be seasonal, means were also calculated for the year pre- and post-change to ensure identical calendar months were compared, and the results were similar (16.6 (s.d. = 9.1) v. 29.6 (s.d. = 7.5), respectively).Longitudinal data on monthly unauthorised absences are presented in P = 0.696). With regard to physical assaults, the mean difference of 2.8 assaults/month, from 11.5 (s.d. = 5.9) before to 14.3 (s.d. = 10.1) after, was also not statistically significant (P = 0.628)  .P = 0.001).Another assessed variable was the longitudinal data on monthly seclusion hours over the study period as well as the mean rates of monthly seclusion (hours/month) . The meaP=0.071). The mean number of monthly admissions to the forensic service increased from 3.1 before the new ward configuration to 4.4 after; however, the increase was not caused by in-patients from the acute in-patient service as a total of 3 patients were transferred from the acute in-patient service to the forensic service for the 18 months prior to the ward change compared with 4 patients in the 18 months following the change.Occupancy was recorded according to bed nights/month and converted to a percentage of available bed nights. Occupancy varied between 80 and 101%, with a mean occupancy of 91% over the study period. It is likely that the single month that experienced more than 100% occupancy was very busy and included extra persons in rooms  being entered in the census data. Percentage occupancy data were largely stable over the study period and were without systematic trends that could account for the significant increases in unauthorised absences or significant reduction in seclusion hours. In keeping with the occupancy data, the rate of new admissions to the acute in-patient service was also largely stable over the study period  revealed that, on average, there were 16 times per month when either a high care area or a whole ward was locked following the change in ward configuration. This meant that on average, each of the four wards had 4 periods each month in which part or the whole of the ward was locked. The frequency of locked periods/month varied from 0 for some wards to a maximum of 19, when the high care area of one ward was locked on multiple occasions in response to a single patient's multiple attempts to leave. In 37% of the environmental restraints, just the high care areas were locked as opposed to whole wards (affecting only 1–3 patients at a time). The mean time an area was locked was 120 minutes, and the range varied from 1 minute to 920 minutes. These results can be compared with the period prior to the new ward configuration, which had two wards (affecting up to 20 patients) constantly locked and occasional periods when the two open wards were locked in response to clinical pressure.The total number of SAC1 and SAC2 events involving in-patients was 14 over the study period. Of these, 10 occurred before the change in ward configuration, 0 occurred during the transition period, and 4 occurred after the changes were made. For SAC1 incidents resulting in the death of a patient, 7 occurred prior to the ward changes  and 4 deaths occurred following the ward changes (3 on the ward and 1 while on granted leave). No SAC2 incidents occurred for patients who were on leave in the community or during an unauthorised absence.This study examined a range of adverse indicators over an extended time period in order to clarify whether or not a change in ward environment from two locked and two unlocked wards to a largely unlocked environment was associated with an increase in adverse events. The principal finding was that a significant increase in unauthorised absences occurred. However, significant decreases in the use of seclusion and non-significant increases in violent outcomes were also observed, although the reduction in seclusion occurred alongside national and local initiatives to minimise the use of seclusion.The new ward configuration still made provision for the locking of wards. However, this was only done for relatively short periods (mean 120 min) and less often than prior to the ward redevelopment, when 2 wards affecting 20 patients were continuously locked. In addition, in 37% of the occasions when locking occurred, only a high care area was locked, meaning that 3 or fewer patients were affected. These numbers suggest that the unlocking of two wards and the change in ward environment did not result in wide-spread or prolonged locking of the new ward configuration.The occupancy and admission data were without systematic trends to explain the changes noted. In addition, there was minimal flow of patients from the acute in-patient service to the forensic service, suggesting that more difficult patients who may be over-represented in adverse incident data were not transferred to forensic services after the wards were reconfigured.7 Although the low base rate of these events makes analysis difficult, it is reassuring for those considering a transition to the provision of a largely unlocked environment that of the 14 SAC1 and SAC2 events occurring over the study period, 10 occurred prior to the ward change and only 4 occurred afterwards. In addition, of the adverse events resulting in the death of a patient, 7 occurred before the ward changes and 4 afterwards. Although total numbers of unauthorised absences increased, there was only one death involving a patient who had left the ward without being granted leave, and it occurred prior to the ward change. All other community deaths over the study period involving in-patients occurred for patients who had been granted leave.Previous studies of unauthorised absences from psychiatric wards have raised concerns about rare but serious adverse events that have occurred while patients are absent.One strength of the study was the routine collection of outcome data by hospital staff who were unaware that the data would later be used for study purposes. As a consequence, changes in reporting behaviour could not arise as a result of study influences because of the retrospective nature of the study conception and design. A further strength is the longitudinal nature of the data-set that allowed us to make before-and-after comparisons and consider longer-term effects, as opposed to solely focusing on the transition period during which staff are adapting to changes. These longer-term effects were thought to be more important in evaluating the impact of the change in environment and can be taken into account by service leaders in other locations considering similar changes. Although the longer-term outcomes were our primary area of interest, it is also reassuring that the transition period did not coincide with any SAC1 or SAC2 events, or a spike in the other adverse events evaluated by the study.Our main limitation was that the study design was not experimental in nature. As the study was uncontrolled, our methodology allows comments to be made on associations between adverse events and the ward changes, but demonstrating causation is not possible. In particular, there was a service initiative to reduce seclusion that started prior to the study period. There were also increases in the numbers of routinely rostered nursing staff on the acute in-patient service after the ward change. This means that the relative influences of the change in ward configuration, the seclusion-reducing initiatives and the changes in nursing numbers on the adverse event rates are hard to quantify. It is therefore possible that increases in seclusion might have been observed if the changes in ward configuration had occurred in isolation. However, it is also reassuring to note that no such increases were seen in the presence of the seclusion reduction focus and nursing number changes that also occurred over the study period.et al4 study also identified an increase in unauthorised absences following changing ward policy. However, after the initial increase, the rate subsequently decreased following an intervention to better manage risk and absconding.4Studies such as ours that have evaluated the impact of unlocking psychiatric wards are rare. We were only able to identify 4 previous studies over 7 decades in our literature review. These studies were largely supportive of unlocking psychiatric wards, although the Molnar 8 in the presence of administrative and clinical support, and scrutiny of seclusion practice. It is likely that the reduction of seclusion hours demonstrated in this study occurred largely as a result of nursing and management strategies already in place to reduce seclusion in our service. However, seclusion hours continued to fall despite the change in ward configuration, meaning that the less restrictive environment did not have a negative impact on seclusion rates or supported the continued reduction of seclusion. Further support for the ability of service improvement initiatives to minimise adverse outcomes is given by the studies of Bowers et al,10 who trialled anti-absconding interventions in acute psychiatric wards with positive results, and the study by Nijman,11 who demonstrated a reduction in aggressive incidents through a systematic focus on aggression alongside an intervention to reduce aggression. These studies suggest the importance of nursing practice interventions in addition to any environmental measures for reducing rates of absconding and aggression.As stated, the unlocking of our in-patient ward should not be viewed in isolation. Although the findings were mixed with respect to adverse outcomes, we suggest that clinical attention and adaptations to nursing practice and clinical care have the ability to mitigate adverse outcomes when changes in environment occur. This conjecture is supported by the ability of some psychiatric units to markedly reduce seclusion ratesAdverse outcomes varied after the change to a largely unlocked environment, with increases in absconding, reductions in seclusion and non-significant increases in violent incidents. The real-world nature of this study does not allow clear inferences to be made regarding whether or not the unlocking of the ward was causally linked to these changes in adverse outcome rates. However, the longer-term nature of the database, with the ability to scrutinise the adverse outcomes pre- and post-change in ward configuration, strengthened the ability of this study to examine the change. The change to a largely unlocked environment was stimulated by a desire to provide care in the least restrictive way possible. Our findings constitute a cautious endorsement of this approach. Although unauthorised absences increased, other adverse outcomes were stable or improved. Thus, providing acute in-patient psychiatric care in a largely unlocked environment appears feasible, particularly in the presence of other service improvement strategies.


The structures reveal new intermediate solvent states of hCA II that provide crystallographic snapshots during restoration of the proton-transfer water network in the active site.Ultrahigh-resolution crystallographic structures of human carbonic anhydrase II (hCA II) cryocooled under CO 2/HCO3−. Although hCA II has been extensively studied to investigate the proton-transfer process that occurs in the active site, its underlying mechanism is still not fully understood. Here, ultrahigh-resolution crystallographic structures of hCA II cryocooled under CO2 pressures of 7.0 and 2.5 atm are presented. The structures reveal new intermediate solvent states of hCA II that provide crystallographic snapshots during the restoration of the proton-transfer water network in the active site. Specifically, a new intermediate water (WI′) is observed next to the previously observed intermediate water WI, and they are both stabilized by the five water molecules at the entrance to the active site (the entrance conduit). Based on these structures, a water network-restructuring mechanism is proposed, which takes place at the active site after the nucleophilic attack of OH− on CO2. This mechanism explains how the zinc-bound water (WZn) and W1 are replenished, which are directly responsible for the reconnection of the His64-mediated proton-transfer water network. This study provides the first ‘physical’ glimpse of how a water reservoir flows into the hCA II active site during its catalytic activity.Human carbonic anhydrase II (hCA II) is a zinc metalloenzyme that catalyzes the reversible hydration/dehydration of CO The remaining three isoforms lack catalytic activity and are referred to as carbonic anhydrase-related proteins (CARPs). Among these isozymes, human CA II (hCA II) is expressed in most cell types, with involvement in many physiological processes  and hydrophobic residues . The ‘hydrophobic’ side sequesters and positions the CO2 for nucleophilic attack by OH−   CO2 pressure  for different time intervals  to decrease the internal CO2 pressure  immediately replace the vacated space as CO2 leaves the active site. In addition, WI (intermediate water), which is only observed in fully CO2-bound hCA II  in close proximity to residue His64 was observed to gradually disappear, whereas His64 concurrently rotated from the ‘out’ to the ‘in’ rotameric conformation. Despite the structural changes observed, the rapid changes taking place with the crystal incubation method left some of the key questions unanswered, such as how the proton-transfer water network is restored during hCA II catalytic activity.Previously, the capture of CO2 pressures of 7.0 atm (0.9 Å resolution) and 2.5 atm (1.0 Å resolution), which are hereafter referred to as ‘7.0 atm CO2 hCA II’ and ‘2.5 atm CO2 hCA II’, respectively. These two structures were compared with the three previous structures , 50 s  and 1 h . The structural comparison reveals that 7.0 atm CO2 hCA II and 2.5 atm CO2 hCA II are previously unknown intermediate states between 15 atm CO2 hCA II and 15 atm CO2 hCA II – 50 s. Together, these studies provide a view of how hCA II utilizes a water reservoir to fill the void in the active site as CO2 is released.In this study, we present ultrahigh-resolution structures of hCA II from crystals cryocooled under CO2.2.1.Escherichia coli BL21 (DE3) pLysS transformed with a plasmid encoding the hCA II gene benzenesulfonamide, which binds to hCA II. The protein on the resin was eluted with 400 mM sodium azide in 100 mM Tris–HCl pH 7.0. The azide was removed by extensive buffer exchange against 10 mM Tris–HCl pH 8.0.The zinc-containing hCA II was expressed in a recombinant strain of 2.2.M sodium citrate, 100 mM Tris–HCl pH 7.8) at room temperature (∼20°C)  glycerol. The crystals were then coated with mineral oil to prevent dehydration and loaded into the base of high-pressure tubes. Once in the pressure tubes, the crystals were pressurized with CO2 gas to two different pressures (7.0 and 2.5 atm) at room temperature. After 10 min, the crystals were cryocooled to liquid-nitrogen temperature (77 K) without releasing the CO2 gas. Once the CO2-bound crystals had been fully cryocooled, the crystal-pressurizing CO2 gas was released and the crystal samples were stored in a liquid-nitrogen dewar until X-ray data collection. Note that once cryocooled, the CO2-bound hCA II crystals were handled just like normal protein crystals and were flash-cryocooled at ambient pressure.CO2.4.2 hCA II data set (0.9 Å resolution), an initial data set consisting of 180 images was collected with 1 s exposures to cover diffraction resolution up to 1.1 Å. The detector was then offset to cover diffraction resolution up to 0.88 Å, and a second data set consisting of 360 images was collected with 10 s exposures. For the 2.5 atm CO2 hCA II data set (1.0 Å resolution), a single data set consisting of 360 images was collected with 10 s exposure for each image. For each X-ray data set, the estimated absorbed X-ray dose was ∼2 × 107 Gy. No significant diffraction resolution decay was observed up to this X-ray dose. Indexing, integration, merging and scaling were performed using HKL-2000  under a nitrogen cold stream (100 K). Data were collected using the oscillation method in intervals of 1° on an ADSC Quantum 270 CCD detector (Area Detector Systems Corporation) with a crystal-to-detector distance of 100 mm. For the 7.0 atm CO2.5.2 pressures of 7.0 and 2.5 atm were determined using the CCP4 program suite , 5yuj (superseding 5dsj) and 5yuk (superseding 5dsn). Details of the structural analysis of the bound water molecules are given in the Supporting Information. All structural figures were rendered with PyMOL (Schrödinger).The structures of hCA II at CO3.3.1.2 hCA II and the other four structures  are 0.14, 0.12, 0.10 and 0.13 Å, respectively. Although changes in the zinc-coordinating histidines  are negligible between the structures, the electron densities for the CO2 binding site differ significantly, as expected , deterioration of electron density for the CO2 site occurs in the 2.5 atm CO2 hCA II structure, represented by sparsely connected lobes . When the density is modelled and refined with only CO2, the CO2 occupancy is at most 0.7. This difference suggests that the CO2 site is occupied by both CO2 and two waters (deep waters WDW and W′DW) at a pressure of 2.5 atm. The manifestation of WDW at this pressure is supported by the extended electron-density connection from CO2 to WI . In 15 atm CO2 hCA II – 50s, the electron density for the CO2 binding site is further shifted towards Zn and WZn, which correlates with the known positions of WDW and W′DW . This argues that 2.5 atm CO2 hCA II has a higher internal CO2 pressure than 15 atm CO2 hCA II – 50s. Finally, in 15 atm CO2 hCA II – 1h, the electron density of the CO2 binding site splits into two distinct lobes, indicating that the CO2 site is completely replaced by WDW and W′DW .Structural examinations show that the five structures are very similar. The all-protein-atom r.m.s.d.s between 15 atm COed Fig. 2. While 1es Fig. 2c. When DW Fig. 2d. This DW Fig. 2e.2 molecule which is 15–16 Å away from the active-site CO2 molecule was reported in a hydrophobic pocket created by Val223 and Phe226 . Interestingly, in the lower pressured 7.0 atm CO2 hCA II, the subdued electron density for the secondary CO2 results in dual conformations of the Phe226 side chain . In the cases of 2.5 atm CO2 hCA II and 15 atm CO2 hCA II – 50s, the secondary CO2 was not present and the Phe226 side chain sits in the position observed in the CO2-free 15 atm CO2 hCA II – 1h . Hence, the observation of the secondary CO2 and the dual conformations of the Phe226 side chain in 7.0 atm CO2 hCA II imply that 7.0 atm CO2 hCA II has a higher internal CO2 pressure than 15 atm CO2 hCA II – 50s.Previously, the binding of a secondary CO3.2.2 binding sites suggest that both 7.0 atm CO2 hCA II and 2.5 atm CO2 hCA II have a higher internal CO2 pressure than 15 atm CO2 hCA II – 50 s. Furthermore, 7.0 atm CO2 hCA II intuitively has a higher internal CO2 pressure than 2.5 atm CO2 hCA II, hence leading to the conclusion that the internal CO2 pressure decreases in the sequence 15 atm CO2 hCA II, 7.0 atm CO2 hCA II, 2.5 atm CO2 hCA II, 15 atm CO2 hCA II – 50s, 15 atm CO2 hCA II – 1h. Such an interpretation ascertains that 7.0 atm CO2 hCA II and 2.5 atm CO2 hCA II are intermediate states that fill the gaps between the 15 atm pressurized CO2 hCA II and the earliest time point of CO2 release (15 atm CO2 hCA II – 50s) observed in the previous study , the electron density of His64 infers that it occupies dual ‘out’ and ‘in’ positions as the internal CO2 pressure decreases . However, in the CO2-free 15 atm CO2 hCA II – 1h, His64 is observed to primarily occupy the ‘in’ position . In concert with His64 moving from the ‘out’ to the ‘in’ position, the density for W2′  is observed to gradually dissipate.Although the side chain of His64 lies predominantly in the ‘out’ position in 15 atm COII Fig. 3a, the eon Fig. 3e. In co2 is fully bound in the 15 atm CO2 hCA II structure, WI but not W1 is observed  necessary for the proton-transfer wire was presumed to be broken when CO2 fully binds to the active site. In this study, we observed the dynamic replacement of WI with W1 as the internal CO2 pressure decreases, since dually occupied positions of W1 and WI are seen for 7.0 and 2.5 atm CO2 hCA II . The reduction of electron density for WI is observed in the order 15, 7.0 and 2.5 atm CO2 hCA II, with complete disappearance in 15 atm CO2 hCA II – 50s and 15 atm CO2 hCA II – 1h  was observed in the structures of 7.0 and 2.5 atm CO2 hCA II . When the previously reported structures were compared, W′I existed in the 15 atm CO2 hCA II and 15 atm CO2 hCA II – 50s structures, but was overlooked because of its faint electron density . Compared with WI, W′I is located farther away from the active site and more towards the entrance that connects the active site of hCA II to bulk solvent. Because the entrance is near the active site where water, substrate and product (CO2/bicarbonate) can interchange/interact with bulk solvent, we will refer to it as the ‘entrance conduit’  that are ordered along the surface of the entrance conduit in the CO2-free 15 atm CO2 hCA II – 1h , WEC2 (W′EC2) and WEC5 (W′EC5) exist in the different internal CO2 pressure structures. Tight hydrogen-bonding networks stabilize WEC1, WEC2, WEC3, WEC4 and WEC5, which are mediated by residues lining the entrance conduit . For instance, the side-chain amide N atom of Gln92 binds to WEC2, and the main-chain carbonyl O atom of Pro201 and the side-chain hydroxyl O atom of Thr200 bind to WEC5, which are conserved throughout all of the internal CO2 pressure structures. Hydrogen-bonding interactions also exist in all of the structures between the five WEC waters .A close inspection of the structures further identified five water molecules . Among the WEC waters, WEC2, WEC3 and WEC5 participate in stabilizing WI, W′I and W1 within all of the structures. For example, hydrogen-bonding interactions with W′I are observed for WEC2, WEC3 and WEC5, while hydrogen-bonding interactions with WI and W1 are observed for WEC2.The intermediate waters WEC waters are present regardless of the different internal CO2 pressures, some perturbations of WEC1 (near to the proton-shuttling His64) and WEC2  were observed during the internal CO2 pressure decrease, which are manifested by multiple alternate positions  in CO2-bound apo CA II in Kim et al. (2016EC1 (named W′EC1 in this study) in 15 and 7.0 atm CO2 hCA II . In these structures, the distances between W3b, W3b′, WEC1 and W′EC1 are so close  that they organize into a continuous tube of electron density . These results suggest that the waters in the proton-transfer network (W1/W2/W2′/W3a/W3b/W3b′), the intermediate waters W′I/WI and the water network of the entrance conduit (WEC1/WEC2/WEC3/WEC4/WEC5) all act interdependently with their motions correlated.Although all five Wns Fig. 5. The dyn al. 2016] was obsty Fig. 5. W3b′ an3.4.2 pressure in hCA II crystals, we captured additional intermediate states, including dual occupied positions of W1 and WI, an active site partially occupied with CO2, WDW and W′DW, a new intermediate water W′I and an alternate position of W3b (W3b′). By realizing that WI and W′I are transiently stabilized by several entrance-conduit water molecules and that they rearrange during the restoration of the proton-transfer water network, we propose the sequential events in the formation of the water network that replenishes WZn and the consequential connection of the His64-mediated proton-transfer wire during the catalytic turnover of hCA II. Although these events have been postulated from the observations during CO2 release in this study, these mechanisms may also account for restoration of the water network after bicarbonate release, assuming that both CO2 and bicarbonate molecules do not directly mediate the water-network restoration process.By lowering the COI, and not W1, is observed near the active site of hCA II in the fully CO2-bound state . Because the distance between WI and W2 is ∼4.8 Å, the lack of W1 suggests that the hydrogen-bonded water network from WZn to His64 (charged and in the ‘out’ position) is disrupted. In fact, when hCA II is fully CO2-bound, the proton transfer should have already happened to result in the deprotonation of WZn to OH−, which is necessary for the nucleophilic CO2 attack . This directional branching movement of WI is predictable since the distance between WI and W1 is 2.0 Å and the distance between WI and WDW is 2.4 Å. This interpretation is further supported by the observation that the electron density of W1 emerges as that of WI disappears , as well as by the observation that the electron density of WI is fused to the electron density of WDW . Subsequently, W1 can move to WZn (the distance between W1 and WZn is 2.6 Å), and WDW can shift to either WZn or W′DW . Judging by the distance from WI to WZn (2.6 Å), WI can also directly flow into the WZn position .It is likely that WDW Fig. 6b. This on Fig. 6b.I replenishes multiple water positions (W1/WDW/W′DW/WZn), it is important that the bulk solvent supplies the WI position rapidly (acting as a water reservoir), a process that seems to be facilitated by W′I. W′I is separated from WI by 2.2 Å, is located closer to the bulk solvent and is transiently stabilized by the dynamic motions of water molecules in the entrance conduit, which take place in concert with the changes of solvent in the active site . In addition, the dynamic motions of water molecules in the entrance conduit decrease as the water network is restored in the active site  via W1/W2/W2′ .As Wte Fig. 5, which c2′ Fig. 6c.4.2 and during its release reveal intermediate snapshots during the water-network rearrangement in the active site as the waters fill the void following CO2 liberation. Based on our observations, insight into the water-network restoration prior to proton transfer is proposed. While previous studies of the catalytic activity of hCA II have mainly focusing on the CO2 binding site (Zn/WZn/WDW) and the proton-transfer water network (W1/W2/W3a/W3b), our results indicate that the intermediate and alternate waters  and the entrance-conduit waters  are critically involved in catalysis by hCA II. The substrate CO2 enters via the hydrophobic half of the active site, while the product HCO3−, being a charged molecule, exits by perturbing the ordered waters that fill the hydrophilic half of the active site . Molecular dynamics simulations on this extended water network may reveal further insights into the bioenergetic mechanisms utilized by hCA II to generate ordered water networks from the surrounding disordered bulk solvent (Riccardi et al., 2006Structural comparisons between hCA II in complex with CO2 hCA II, 5y2r2.5 atm COPDB reference: 2 hCA II, 5y2s7 atm COPDB reference: 2 hCA II, re-refined, 5yui15 atm COPDB reference: 2 hCA II – 50s, re-refined, 5yuj15 atm COPDB reference: 2 hCA II – 1h, re-refined, 5yuk15 atm COPDB reference: 10.1107/S2052252517017626/mf5021sup1.pdfSupplementary information, figures and table.. DOI:


It is found Mg2+ ion doping affects the crystal field symmetry around RE3+ ions and enhance the upconversion emission intensity. Bright white-light is obtained when the Mg2+ ion concentration is 0.5 mol% in the melt. And the CIE coordinates are hardly changed with Mg2+ ion doping. In addition, the upconversion mechanism is discussed in detail. It is observed the longer lifetimes of intermediate levels result in the lower upconversion photon numbers, which are beneficial to the upconversion process. Therefore, Mg2+ ion doped Ho3+/Yb3+/Tm3+/LiNbO3 single crystals would have potential applications in stable white-light devices and photoelectric instruments.A strategy to enhance the upconversion white-light intensity via Mg As known, upconversion is an anti-stokes process which can convert two or more low-energy photons into a high-energy photon. To avoid the intrinsic color balance, device complication and high cost problems when using multiphosphors, the blue, green and red emissions are expected to be generated simultaneously in a host material. The single white-light phosphors are pursued8. At present, many researches focus on the tri-doped Yb3+, Ho3+ and Tm3+ system in different host materials11, where the Yb3+ ions act as sensitizers to efficiently absorb the pump photons and transfer their energy to Tm3+ or Ho3+ ions. As a result, the blue emission (Tm3+), green and red emissions (Ho3+) are achieved, which can further produce the white-light emission.Recently, trivalent rare earths  in RE3+ ions doped upconverting materials19. Luitel et al. have studied the effects of M+  ion in CaMoO4:RE3+,Yb3+  phosphors20. Guo et al. revealed that the Li+ doping could enhance the emission intensity of Yb3+/Ho3+ codoped Lu6O5F8 nanoparticles21. Many researches show that the codoping of non-luminous ions into RE3+ ions doped upconverting materials is a promising way to increase the intensity of upconversion emission. But the relative studies are still limited, to the best of our knowledge, few reports concerned about the influence of non-luminous ions on upconversion white-light properties in RE3+ ions doped materials to date.Worthy of notice, in addition to the presence of RE3 single crystal was used as host material, its lower phonon energy guarantees the higher upconversion efficiency. Mg2+ ion was introduced into Ho3+/Yb3+/Tm3+ tri-doped LiNbO3 single crystals due to its small ionic radius. Here, we represent a new strategy to improve the properties of upconversion white-light emission. Under 980 nm excitation, the influences of Mg2+ ion on the intensity and color tunability of upconversion white-light emission were demonstrated and the rational explanation was given. Preferably, the multi-function of LiNbO3 single crystal will create sufficient conditions for opening up new perspectives to the studies of integration and tiny devices.In this article, LiNbO2+ doped Ho3+/Yb3+/Tm3+/LiNbO3 crystals. It can be seen that the Mg2+ and RE3+ ions are introduced into the crystals successfully. With increasing Mg2+ ion concentrations in the melt, Mg2+ ion concentrations in the crystals are increased evidently. However, the total concentrations of RE3+ ions in the crystals are decreased slightly with increasing Mg2+ ion concentrations, which could be considered as unchanged. In addition, Fig. 3 and Ho3+/Yb3+/Tm3+/LiNbO3 single crystals doped with different Mg2+ ion concentrations. As shown, all the diffraction peaks of the samples can be well indexed to the standard LiNbO3 phase (JCPDS file no. 20-0631), no secondary phases were identified. It can be concluded that the doping ions do not alter the phase structure of host material, and the ionic radius differences between doping ions and host ions result in the variations of diffraction peak intensities. To further investigate the effect of Mg2+ ions on the structure of Ho3+/Yb3+/Tm3+/LiNbO3 single crystal, the main diffraction peak is amplified, as shown in Fig. 3+ ions with larger ionic radius  will enter into the LiNbO3 crystals in the form of lattice substitution. So the host lattice is expanding, which could lead to the shift of the main diffraction peak towards smaller angle, as shown in Fig. 2+ ions with smaller ionic radius (rMg2+ = 0.66 Å) may enter into the crystals in the form of lattice substitution or interstitial. For lattice substitution, the host lattice shrinking is induced since the ionic radius of Mg2+ ion is smaller than that of Li+ or Nb5+ ions, corresponding to the shift of the main diffraction peak towards larger angle. By contrast, for the interstitial, the host lattice expanding occurs, resulting in the shift of the main diffraction peak towards smaller angle. Based on the above mentioned, the site occupancy of Mg2+ ion is mainly indentified by the shift of the main diffraction peak. It can be seen from Fig. 2+ ion concentrations, the main diffraction peak shifts gradually towards smaller angles, which means the lattice is expanding and the Mg2+ ions enter into the crystals in the form of interstitial. As a result, the occupation of interstitial site for Mg2+ ion can tailor the local crystal field around RE3+ ions in the host lattice, which will affect its luminescence properties.Table 3+/Yb3+/Tm3+/LiNbO3 single crystals doped with various Mg2+ ion concentrations under 980 nm excitation are shown in Fig. 3+: 1G4 → 3H6 transition; the green emission band centered around 549 nm is contributed to Ho3+: 5S2, 5F4 → 5I8 transition; and the red emission has luminescence peaks at 652 nm and 665 nm originating from Tm3+: 1G4 → 3F4 transition and Ho3+: 5F5 → 5I8 transition, respectively. From Fig. 2+ ion concentrations. The optimum Mg2+ ion concentration is 0.5 mol% in the melt, corresponding to 0.66 mol% in the single crystal. In our case, we argue that Mg2+ ion with small ionic radius can be doped into the host lattice easily in the form of interstitial according to the XRD results, and this will break the symmetry of the crystal field around the rare earth ions. If the rare earth ions are placed at a low symmetry site, the forbidden transitions will be weakened, leading to the enhancement of upconversion emission. The similar phenomena are also found in the research reports, such as refs23. But when the Mg2+ ion concentration is above optimum concentration, the doped ions may cause the lattice distortion around the rare earth ions, resulting in the quenching of the upconversion emission. To investigate the color tunability, Fig. 3+/Yb3+/Tm3+/LiNbO3 single crystals doped with various Mg2+ ion concentrations. It can be seen that the CIE coordinates of samples undoped and doped Mg2+ ion are located in the white-light region basically. Moreover, the CIE coordinates have the trend of shift towards green/red region first and then tend to shift towards blue region with increasing the Mg2+ ion concentrations. But it should be noted that it shows little color tunability under Mg2+ ion doping. So the Mg2+ ion doped Ho3+/Yb3+/Tm3+/LiNbO3 single crystals may be suitable for making the non-tunable white-light display devices.The upconversion emission spectra of Ho2+ ions doped Ho3+/Yb3+/Tm3+/LiNbO3 single crystal, the dependences of upconversion emission intensities on pump powers are measured under 980 nm excitation, as shown in Fig. 2+ ion doping, the slopes of blue, green, and red emissions for Ho3+/Yb3+/Tm3+/LiNbO3 single crystal are 2.30, 1.78, and 1.63, respectively. It can be obtained that the blue emission is a three-photon process, the green and red emission are two-photon processes. When the Mg2+ ion concentration in the melt is 0.5 mol%, the slopes of blue, green, and red emissions are 1.52, 1.02, and 0.96, respectively. And when the Mg2+ ion concentration in the melt reaches up to 4.0 mol%, the above values are 1.65, 1.14, and 1.01, respectively. As known, the slopes deviating from the integer values (3 or 2 or 1) are attributed to the competition between the linear decay and the upconversion processes for the depletion of the intermediate excited states and the local thermal effect25. These results indicate that the blue emission is a two-photon process, the green and red emission are one-photon processes with Mg2+ ion doping. As a supplement, the luminescence decay behaviors of Ho3+: 5I6 → 5I8 (λem = 1150 nm), Ho3+: 5I7 → 5I8 (λem = 2000 nm), and Tm3+: 3F4 → 3H6 (λem = 1800 nm) are investigated, as shown in Fig. 26.I(t) is the fluorescence intensity at time t, I0 stands for the background fluorescence intensity, τs and τf represent slow fluorescence lifetime and fast fluorescence lifetime, As and Af are the weight factor of slow fluorescence lifetime and fast fluorescence lifetime, respectively. The lifetime of fluorescence level τ can be calculated according to the fitting results by equation , the lattice distortion plays an important role in upconversion process, so the upconversion luminescence is not emitted effectively though the lifetime of its intermediate level is long, the upconversion emission intensity is decreased consequently. Furthermore, the decay curve analysis of the excited levels involved in the following upconversion emission processes Tm3+: 1G4 → 3H6 (λem = 477 nm), Ho3+: 5F4, 5S2 → 5I8 (λem = 550 nm), and Ho3+: 5F5 → 5I8 (λem = 665 nm) are performed and calculated, the obtained lifetime values are shown in Table 2+ ion incorporation modifies the crystal field and results in the fast emitting of upconversion luminescence, and hence the upconversion emission intensity is enhanced. But the excessive Mg2+ ion concentration is detrimental to the enhancement of upconversion emission intensity.The obtained lifetime values are shown in Table 2+ ions doped Ho3+/Yb3+/Tm3+/LiNbO3 system under 980 nm excitation have been described in Fig. 3+ ions act as sensitizers to absorb laser photons and transfer their energy to Ho3+ and Tm3+ ions effectively. Through two successive energy transfer processes from Yb3+ ions to Ho3+ ions, the 5F4, 5S2 levels and 5F5 levels of Ho3+ ions are populated, which generate the upconversion green and red emissions, respectively. Similarly, through three successive energy transfer processes from Yb3+ ions to Tm3+ ions, the upconversion blue emissions and weak red emissions are obtained originating from the 1G4 → 3H6 and 1G4 → 3F4 transitions of Tm3+ ions. In the upconversion processes, Mg2+ ion is not the luminescent ion. The doping Mg2+ ions can impact the lifetimes of excited levels, and further influence the upconversion emission intensity.The Schematics of populating and upconversion luminescence processes for the blue, green and red emissions in the Mg2+-doped Ho3+/Yb3+/Tm3+/LiNbO3 single crystals have been successfully prepared by Czochralski method. Bright upconversion white-light emission is achieved under 980 nm excitation at room temperature. It is found that Mg2+ and RE3+ ions could not alter the phase structure of host material, Mg2+ ions enter into the single crystals in the form of interstitial. The intensities of upconversion emissions are increased firstly and decreased subsequently with increasing Mg2+ ion concentrations. The optimum Mg2+ ion concentration is 0.5 mol% in the melt. The red, green and blue emissions in this system can be ascribed to Ho3+: 5F5 → 5I8, Tm3+: 1G4 → 3F4; Ho3+: 4S2, 5F4 → 5I8 and Tm3+: 1G4 → 3H6 transitions, respectively. The research results indicate that Mg2+ ion doping could not change the upconversion processes of Ho3+, Yb3+, and Tm3+ ions in LiNbO3 single crystals. The enhancement of upconversion emission intensity is mainly attributed to the increase of lifetimes for intermediate levels and the decrease of lifetimes for luminescent levels. Besides, it can be obtained that the CIE coordinates of upconversion emissions are almost unchanged with Mg2+ ion doping, which show ideal non-tunable white-light emissions. Such excellent white-light in Mg2+ ion doped Ho3+/Yb3+/Tm3+/LiNbO3 single crystals make it have potential applications in stable white-light devices and photoelectric instruments. This method would stimulate the further discovery to enhance the upconversion white-light intensity and fabricate other stable white-light materials.Mg3+/Yb3+/Tm3+/LiNbO3 single crystals doped with different Mg2+ ion concentrations were grown by the Czochralski method. The concentrations of Ho3+, Yb3+ and Tm3+ ions in the melts were 0.025 mol%, 2.0 mol% and 0.2 mol%, respectively. And the Mg2+ ion concentrations in the melts are 0.0 mol%, 0.2 mol%, 0.5 mol%, 2.0 mol% and 4.0 mol%. The single crystals doped with different Mg2+ ion concentrations in the melt are denoted as 0.0 Mg, 0.2 Mg, 0.5 Mg, 2.0 Mg and 4.0 Mg in this article. The raw materials were Li2CO3, Nb2O5, Ho2O3, Yb2O3, Tm2O3 and MgO with 4 N purity. Firstly, the doped LiNbO3 polycrystals were prepared by high temperature solid state method. The raw materials were weighed and thoroughly mixed for 48 h, underwent a heat treatment of 750 °C for 2 h to resolve Li2CO3 into Li2O and CO2, and then sintered at 1150 °C for 10 h to form polycrystals. Secondly, the doped LiNbO3 single crystals were grown along the [0 0 1] direction using a diametercontrolled Czochralski apparatus. To grow crystals with good quality, the following optimum growth conditions were selected: the temperature gradient above the melt was 25 °C/mm, the pulling rate was 0.2 mm/h, and the seed rotation rate was 28 rpm. After growth, the crystals were cooled down to room temperature at a speed of 30 °C/h. For phase structure analyses, the samples were grinded into powder using an agate mortar. And for optical tests, Y-cut plates of the samples were cut and polished.The HoThe datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.2+ ions and rare earth ions (RE3+) in the single crystals. To identify the crystallization phase, X-ray diffraction spectra of Mg2+ ion doped Ho3+/Yb3+/Tm3+/LiNbO3 single crystals were measured by an XRD-6000 diffractometer using a copper Kα radiation source. The upconversion luminescence spectra were recorded by Zolix-SBP300 grating spectrometer equipped with CR131 photomultiplier under 980 nm excitation. In the measurement of luminescence decay dynamics, the continuous wave from 980 nm laser diode was tuned into pulsing by a signal generator, and the luminescence decay curves were measured by a digital phosphor oscilloscope (Tektronix DPO 4140). The CIE chromaticity coordinate for the upconversion fluorescence of Mg2+-doped Ho3+/Yb3+/Tm3+/LiNbO3 single crystal was calculated based on the 1931 CIE standard and marked in the CIE standard chromaticity diagram.The Inductively Coupled Plasma Mass Spectrometry (ICP-MS) with Optima-7500 type was used to measure the mass fractions of Mg