bluuebunny/crossref_metadata_2025 huggingface dataset:
Associations Between Gender-Specific Substance Use Patterns and Mental Health Among Adolescents in the Republic of Korea
Authors: Lee Haein , Lee Bo Gyeong
Published: September 2023

Purpose

Although gender differences in adolescent substance use are complex and substance use accompanies mental health problems, most previous studies have focused on gender-specific association between single substance use and mental health. This study aimed to investigate gender-specific substance use patterns and to examine their association with mental health characteristics.

Methods

Nationally representative data from the Korea Youth Risk Behavior Survey collected in 2018 were analyzed. To identify substance use patterns among male adolescents (n = 30,463) and female adolescents (n = 29,577), multiple-group latent class analysis was conducted using eight substance use indicators. In addition, we conducted a latent class analysis with covariates to examine the association between substance use patterns and mental health characteristics.

Results

Among both gender samples, the four-class model best fit the data: nonusers (86.4%), frequent smokers (2.9%), risky drinkers (7.1%), and heavy tobacco and alcohol users with lifetime heated tobacco product use (3.6%) for male adolescents, and nonusers (89.8%), frequent smokers (0.5%), risky drinkers (8.0%), and heavy tobacco and alcohol users with a drunkenness episode (1.7%) for female adolescents. Depression, suicidal plans, and suicidal attempts predicted the latent class model for both genders. In addition, stress level predicted the latent class model for female adolescents.

Conclusions

The findings indicate that homogeneous patterns of substance use by gender are differentially associated with mental health problems. Therefore, health professionals should develop interventions tailored to gender-specific substance use patterns, taking into account the mental health characteristics of each pattern.
Prescription Stimulant Misuse Among Nursing Students
Authors: Magnotti Sebastian , Beatty Avery , Bickford Erek , Channell Isabella , Weyandt Lisa
Published: September 2023

Nonmedical prescription stimulants are used to reduce symptoms of inattention, impulsivity, and hyperactivity in children and adults with attention-deficit hyperactivity/disorder. They are Schedule II controlled substances because of their high potential for dependence, and individuals who misuse them without a valid prescription are subject to criminal charges. Stimulant medications are also associated with common side effects (e.g., insomnia) as well as more serious but less common side effects (e.g., arrhythmias). Despite the potential health and legal consequences, misuse of prescription stimulants has become a public health crisis on college campuses in the United States. Neurocognitive enhancement is the primary reason that college students report misusing prescription stimulants, despite no enhancement of cognitive functioning when taken by healthy adults. Nursing students may be at risk for misuse because of their high levels of academic and clinical demands and because many start misusing in nursing school. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, the databases PubMed, Science Direct, EBSCOhost, and Academic OneFile were systematically searched to investigate the (a) percentage of prescription stimulant misuse studies that have included nursing students, (b) prevalence of prescription stimulant misuse among nursing students, (c) motivations for prescription stimulant misuse among nursing students, and (d) demographic factors associated with increased use among nursing students. Results revealed that of the 197 studies conducted within the past decade (2010–2021), only 1.02% (two) included nursing students. Future studies must investigate the prevalence and nature of prescription stimulant misuse among nursing students.
The impact of serum estradiol and progesterone levels during implantation on obstetrical complications and perinatal outcomes in frozen embryo transfer
Authors: Lin Yi-Lun , Ho Chung-Han , Chung Ming-Ting , Lin Liang-Yin , Hsiao Tsun-Wen , Chen Yi-Ting , Wen Jen-Yu , Tsai Yung-Chieh
Published: September 2023

Background:

This study sought to evaluate obstetric complications and perinatal outcomes in frozen embryo transfer (FET) using either a natural cycle (NC-FET) or a hormone therapy cycle (HT-FET). Furthermore, we investigated how serum levels of estradiol (E2) and progesterone (P4) on the day of and 3 days after embryo transfer (ET) correlated with clinical outcomes in the two groups.

Methods:

We conducted a retrospective, single-center study from January 1, 2015, to December 31, 2019. The study included couples who underwent NC-FET or HT-FET resulting in a singleton live birth. Serum levels of E2 and P4 were measured on the day of and 3 days after ET. The primary outcomes assessed were preterm birth rate, low birth weight, macrosomia, hypertensive disorders in pregnancy, gestational diabetes mellitus, postpartum hemorrhage, and placenta-related complications.

Results:

A total of 229 singletons were included, with 49 in the NC-FET group and 180 in the HT-FET group. There were no significant differences in obstetric complications and perinatal outcomes between the two groups. The NC-FET group had significantly higher serum levels of P4 (17.2 ng/mL vs 8.85 ng/mL; p < 0.0001) but not E2 (144 pg/mL vs 147 pg/mL; p = 0.69) on the day of ET. Additionally, 3 days after ET, the NC-FET group had significantly higher levels of both E2 (171 pg/mL vs 140.5 pg/mL; p = 0.0037) and P4 (27.3 ng/mL vs 11.7 ng/mL; p < 0.0001) compared with the HT-FET group.

Conclusion:

Our study revealed that although there were significant differences in E2 and P4 levels around implantation between the two groups, there were no significant differences in obstetric complications and perinatal outcomes. Therefore, the hormonal environment around implantation did not appear to be the primary cause of differences in obstetric and perinatal outcomes between the two EM preparation methods used in FET.
Four Assessment Tools for Predicting Mortality and Adverse Events in Surgical Patients With Sepsis and Septic Shock: A Comparative Study
Authors: CHU Yi-Chin , LIU Yi , WENG Shih-Feng , CHEN Chao-Wen
Published: September 2023

Background

The mortality rate for sepsis and septic shock in surgical patients is approximately 36%, which is higher than that of other medical patients. Predisposition, infection/injury, response, and organ dysfunction (PIRO) is currently the most widely used tool for assessing patients with surgical sepsis. However, it is not a standardized assessment tool for surgical patients in general.

Purpose

The purposes of this study were to (a) create a modified PIRO (mPIRO) that adds a count of platelets and does not include a body temperature reading; (b) test the sensitivity and specificity of the mPIRO for predicting mortality and adverse events among patients with surgical sepsis; and (c) compare the predictive accuracy of the mPIRO, sequential organ failure assessment (SOFA), quick SOFA, and PIRO tools.

Methods

A retrospective observational cohort study was conducted. Two thousand fifty-five patient medical records were reviewed, with 103 identified as meeting the inclusion criteria.

Results

Compared with the other tools, mPIRO ≥ 4 achieved better sensitivity (90.5%) in predicting mortality and high sensitivity (72%) and specificity (80%) in predicting adverse events. mPIRO was the most accurate predictor of mortality (area under the receiver operating characteristic curve [AUC] = 0.83) among the tools considered. SOFA and mPIRO were the first and second most accurate predictor of adverse events, respectively, with respective AUC values of 0.86 and 0.82.

Conclusions/Implications for Practice

mPIRO, which employs an easy-to-use scoring system, is a valid assessment tool with good sensitivity and AUC for predicting both mortality and adverse events in patients with surgical sepsis. We recommend using mPIRO ≥ 3 as an indicator of potential adverse events.
Multimodal Management With Immunotherapy, Radiation, and Surgery of Histiocytic Sarcoma Following Acute Lymphoblastic Leukemia: An Unusual Presentation of a Rare Disease
Authors: Ahmad Hufsa , Vallance Kelly , Sharma Ishna , Berry Stacey , Orr Kaci , Ray Anish
Published: September 2023

Histiocytic sarcoma (HS) is a rare neoplasm with no known cause. This sarcoma is characterized by morphology similar to that demonstrated by mature tissue histiocytes and mostly afflicts adults. HSs typically have a poor prognosis due to a rapidly progressive clinical course. Our patient’s case was unique due to its presentation four years after completion of treatment for B-cell acute lymphoblastic leukemia. The patient experienced progression with initial therapy for HS. With dual immunotherapy and radiation, however, the patient has remained clinically stable without detectable disease. Immunotherapy may be a successful and tolerable therapeutic option for histiocytic disease.
Pediatric Optic Pathway Gliomas: A Report From Northern Greece
Authors: Panagopoulou Paraskevi , Athanasiadis Dimitrios , Αnastasiou Αthanassia , Zafeiriou Dimitrios , Papakonstantinou Εvgenia
Published: September 2023

Optic pathway gliomas (OPGs) are the most common pediatric optic nerve tumors. Their behavior ranges between rapid growth, stability, or spontaneous regression. Τhey are characterized by low mortality albeit with significant morbidity. We present the characteristics, management, and outcome of 23 OPG patients (16 females, median age: 4.8 y) managed in a Pediatric Oncology Department in Northern Greece over a 25-year period. Overall, 57% had a background of neurofibromatosis type 1. Diagnosis was based on imaging (10 patients) or biopsy (13 patients). Presenting symptoms were mostly visual impairment/squint (52%). Proptosis/exophthalmos, raised intracranial pressure, and headache were also noted. In 2 occasions, it was detected with surveillance magnetic resonance imaging in the context of neurofibromatosis type 1. Eight patients had unilateral and 2 bilateral optic nerve tumors (Modified Dodge Classification, stage 1a/1b), 3 had chiasmatic (stage 2a/b), and 10 had multiple tumors (stage 3/4). Predominant histology was pilocytic astrocytoma (77%). Management included: observation (4), chemotherapy only (9), surgery only (3), or various combinations (7). Chemotherapy regimens included vincristine and carboplatin, vinblastine, or bevacizumab with irinotecan. Most patients demonstrated a slow disease course with complete response/partial response to chemotherapy and/or surgery, whereas 39% presented ≥1 recurrences. After a median follow-up of 8.5 years (range to 19 y), 20 patients (87%) are still alive with stable disease, in partial/complete remission, or on treatment.
Dyadic Hair Cortisol Self-Collection Procedure
Authors: Anderson Alison R. , Mahajan Ishika , Ford Jodi L. , Wright Kathy D. , Mackos Amy R. , Rose Karen M. , Monroe Todd B. , Moss Karen O.
Published: September 2023

Background

At-home self-collection of specimens has become more commonplace because of measures taken in response to the coronavirus pandemic. Self-collection of hair cortisol is important because chronic stress is present in many populations, such as older adults living with Alzheimer’s disease and their family caregivers. For the evaluation of chronic stress, scalp hair can be used as a predictive biomarker because it examines the cumulative, retrospective stress from previous months.

Objectives

The aim of the paper is to provide a study procedure for at-home, scalp hair self-collection for cortisol concentration analysis from dyads consisting of a person living with Alzheimer’s disease and their family caregiver.

Methods

After informed electronic consent is obtained, a package containing the necessary tools for self-collection of hair samples from the dyad is mailed to the participant’s home. Participants are provided detailed print and video multimedia guides outlining how to obtain the hair samples. Ideally, the hair samples are obtained during the virtual data collection meeting with research personnel. Participants mail back the hair sample in a prepaid package to the biomedical laboratory for analysis.

Discussion

At-home, self-collection of hair provides potential advantages such as reduced participant burden, especially for vulnerable populations where transportation and different environments are challenging. At-home sample collection options may increase research participation and can be applied to multiple research foci. Research considerations for dyads, such as people living with Alzheimer’s disease and their caregivers, are discussed.
Comprehensive Clinical-Pathologic Assessment of Malignant Phyllodes Tumors
Authors: Turashvili Gulisa , Ding Qingqing , Liu Yi , Peng Limin , Mrkonjic Miralem , Mejbel Haider , Wang Yihong , Zhang Huina , Zhang Gloria , Wang Jigang , Wei Shi , Li Xiaoxian
Published: September 2023

The latest World Health Organization classification of breast tumors recommends diagnosing malignant phyllodes tumors (MPTs) when all 5 morphologic features are present: permeative borders, marked stromal cellularity, marked stromal cytologic atypia, ≥10 mitoses per 10 high-power fields (HPF), and stromal overgrowth. We assessed the performance of this recommendation to capture MPTs and features predictive of distant metastasis in a multi-institutional retrospective study. Of 65 MPTs, most cases had at least focally permeative borders (58, 89%), with marked stromal cellularity in 40 (61.5%), marked atypia in 38 (58.5%), ≥10 mitoses per 10 HPF in 50 (77%), and stromal overgrowth in 56 (86%). Distant metastases were observed in 20 (31%) patients (median follow-up 24.5 mo, 1 to 204). Only 13 of 65 (20%) cases had all 5 morphologic features, while only 7 of 20 (35%) cases with distant metastases had all 5 features. In univariate analysis, only marked stromal atypia (P=0.004) and cellularity (P=0.017) were associated with decreased distant metastasis-free survival. In multivariate Cox regression, the combination of stromal overgrowth, marked stromal cellularity, and atypia (C-index 0.721, 95% CI: 0.578, 0.863) was associated with decreased distant metastasis-free survival. The current World Health Organization recommendation will miss a significant number of MPTs with distant metastases. We propose refined diagnostic criteria for MPTs: (1) stromal overgrowth combined with ≥1 feature(s) (marked cellularity, marked atypia, or ≥10 mitoses per 10 HPF), or (2) in the absence of stromal overgrowth, marked cellularity combined with ≥1 feature(s) (permeative borders, marked atypia, or ≥10 mitoses per 10 HPF).
Improved Reverse Postauricular Island Flap for Repair of Lower Conjunctival Fornix Retraction
Authors: Fan Jincai , Guo Rui
Published: September 2023

Repair of lower conjunctival fornix retraction is a great challenge for plastic surgeons in the aspects of orbital prosthesis retaining and cosmetic appearance. Hereby, a 25-year-old woman, suffering from lower conjunctival fornix retraction after the removal of retinoblastoma and radiotherapy, was undertaking the treatment with an improved reverse postauricular island flap for expansion of the lower conjunctival fornix, and volume augmentation of the anophthalmic socket in one stage. The flap was based on the parietal branch of the superficial temporal artery and its vascular architecture to the postauricular vascular system, and successfully transferred by passing through a subcutaneous tunnel. The satisfactory result indicated that the mentioned technique may be a good option in surgical rehabilitation of the stable depth of the lower conjunctival fornix, not only from the reliable blood supply and the suitable thickness of the flap but also from the less donor morbidity without an exposed unsightly scar.

Level of Evidence:

Level V.
An ACS-NSQIP Data Analysis of 30-Day Outcomes Following Surgery for Bell’s Palsy
Authors: Knoedler Samuel , Knoedler Leonard , Hoch Cosima C. , Kauke-Navarro Martin , Kehrer Andreas , Friedman Leigh , Prantl Lukas , Machens Hans-Guenther , Orgill Dennis P. , Panayi Adriana C.
Published: September 2023

Background:

There exists a paucity of large-scale, multi-institutional studies that investigate the outcomes of surgery for Bell’s palsy (BP). Here, we utilize a large, multi-institutional database to study the risk factors and early-stage outcomes following surgical procedures in BP.

Methods:

We reviewed the American College of Surgeons National Surgical Quality Improvement Program database (2008–2019) to identify patients who underwent surgery for the diagnosis of BP. We extracted data on comorbidities and preoperative blood values, and 30-day postoperative outcomes.

Results:

Two hundred fifty-seven patients who underwent surgery for BP symptoms over the 12-year review period were identified. Muscle grafts (n=50; 19%) and fascial grafts (n=48; 19%) accounted for the majority of procedures. The most common comorbidities were hypertension (n=89; 35%) and obesity (n=79; 31%). Complications occurred in 26 (10.1%) cases. Additionally, length of hospital stay was significantly associated with both surgical and medical complications (3.9±4.7 versus 1.5±2.0; P<0.01) and (3.2±3.8 versus 1.4±2.0; P<0.01), respectively. Preoperative creatinine, blood urea nitrogen, and alkaline phosphatase were identified as potential predictors of poor postoperative outcomes.

Conclusion:

Based on multi-institutional analysis, complication rates following surgery for BP were found to be overall low and seen to correlate with length of hospital stay. Reoperations and readmissions were the most frequent complications after surgery for BP. The preoperative evaluation of routine laboratory values may help refine patient eligibility and risk stratification. In addition, our findings call for future large-scale prospective studies in the field of facial palsy surgery to further improve the quality of care and optimize perioperative protocols.
INITIATION TIMING OF VASOPRESSOR IN PATIENTS WITH SEPTIC SHOCK: A SYSTEMATIC REVIEW AND META-ANALYSIS
Authors: Ye Enci , Ye Hui , Wang Shengyao , Fang Xiangming
Published: September 2023

Background:Vasopressor plays a crucial role in septic shock. However, the time for vasopressor initiation remains controversial. We conducted a systematic review and meta-analysis to explore its initiation timing for septic shock patients.Methods:PubMed, Cochrane Library, Embase, and Web of Sciences were searched from inception to July 12, 2023, for relevant studies. Primary outcome was short-term mortality. Meta-analysis was performed using Stata 15.0.Results:Twenty-three studies were assessed, including 2 randomized controlled trials and 21 cohort studies. The early group resulted in lower short-term mortality than the late group (OR [95% CI] = 0.775 [0.673 to 0.893],P= 0.000,I2= 67.8%). The significance existed in the norepinephrine and vasopressin in subgroup analysis. No significant difference was considered in the association between each hour’s vasopressor delay and mortality (OR [95% CI] = 1.02 [0.99 to 1.051],P= 0.195,I2= 57.5%). The early group had an earlier achievement of target MAP (P< 0.001), shorter vasopressor use duration (P< 0.001), lower serum lactate level at 24 h (P= 0.003), lower incidence of kidney injury (P= 0.001), renal replacement therapy use (P= 0.022), and longer ventilation-free days to 28 days (P< 0.001).Conclusions:Early initiation of vasopressor (1–6 h within septic shock onset) would be more beneficial to septic shock patients. The conclusion needs to be further validated by more well-designed randomized controlled trials.
Metabolomic and Proteomic Changes in Trauma-induced Hypocalcemia
Authors: Schaid Terry R. , LaCroix Ian , Cohen Mitchell J. , Hansen Kirk C. , Moore Ernest E. , Sauaia Angela , Cralley Alexis L. , Thielen Otto , Hallas William , Erickson Christopher , Mitra Sanchayita , Dzieciatkowska Monika , Silliman Christopher C. , D’Alessandro Angelo
Published: September 2023

Background

Trauma-induced hypocalcemia is common and associated with adverse outcomes, but the mechanisms remain unclear. Thus, we aimed to characterize the metabolomic and proteomic differences between normo- and hypocalcemic trauma patients to illuminate biochemical pathways that may underlie a distinct pathology linked with this clinical phenomenon.

Methods

Plasma was obtained on arrival from injured patients at a Level 1 Trauma Center. Samples obtained after transfusion were excluded. Multiple regression was used to adjust the omics data for injury severity and arrival base excess prior to metabolome- and proteome-wide comparisons between normo- (ionized Ca2+ > 1.0 mmol/L) and hypocalcemic (ionized Ca2+ ≤ 1.0 mmol/L) patients using partial least squares-discriminant analysis. OmicsNet and Gene Ontology were used for network and pathway analyses, respectively.

Results

Excluding isolated traumatic brain injury and penetrating injury, the main analysis included 36 patients (n = 14 hypocalcemic, n = 22 normocalcemic). Adjusted analyses demonstrated distinct metabolomic and proteomic signatures for normo- and hypocalcemic patients. Hypocalcemic patients had evidence of mitochondrial dysfunction (TCA cycle disruption, dysfunctional fatty acid oxidation), inflammatory dysregulation (elevated DAMPs, activated endothelial cells), aberrant coagulation pathways, and proteolytic imbalance with increased tissue destruction.

Conclusions

Independent of injury severity, hemorrhagic shock, and transfusion, trauma-induced hypocalcemia is associated with early metabolomic and proteomic changes that may reflect unique pathology in hypocalcemic trauma patients. This study paves the way for future experiments to investigate mechanisms, identify intervenable pathways, and refine our management of hypocalcemia in severely injured patients.
Predictive value of neutrophil extracellular traps components for 28-day all-cause mortality in patients with cardiac arrest: A pilot observational study
Authors: Li Peijuan , Liang Shuangshuang , Wang Ling , Guan Xiaolan , Wang Jin , Gong Ping
Published: September 2023

Background

Ischemia–reperfusion after cardiac arrest activates peptidyl arginine deiminase and citrullinates histone H3 (CitH3), which leads to the formation of neutrophil extracellular traps (NETs). This study attempted to determine the alterations in NET components in post-cardiac arrest patients as well as analyze the association of NETs with 28-day all-cause mortality.

Methods

In this study, 95 patients with return of spontaneous circulation (ROSC) after cardiac arrest were included. They were categorized into the survivor group (n= 32) and the nonsurvivor group (n= 63) according to their 28-day survival statuses. The control group comprised 20 healthy individuals. The blood samples were collected from the patients on Days 1, 3, and 7 after ROSC and from the control subjects at the time of enrollment. The serum cell-free DNA (cfDNA) level was determined using the fluorescent labeling method, and the serum concentrations of NETs components, including CitH3, myeloperoxidase (MPO), neutrophil elastase (NE), and nucleosomes, were estimated using the enzyme-linked immunosorbent assay.

Results

Compared with the control group, the serum NET components were significantly increased in the patients 1 week after ROSC (allP< 0.05). These components were significantly higher in the nonsurvivor group than in the survivor group (allP< 0.05). Spearman’s correlational analysis revealed that the components were positively correlated with APACHE II scores (bothP< 0.05). Binary logistic regression analysis indicated that serum cfDNA, CitH3, and nucleosomes on Days 1 and 3 after ROSC were independent predictors of 28-day all-cause mortality. Furthermore, these parameters on Day 1 after ROSC had the biggest areas under the ROC curves (0.876, 0.862, and 0.861, respectively).

Conclusions

Elevated serum levels of cfDNA, CitH3, MPO, NE, and nucleosomes were positively correlated with disease severity after ROSC. However, only serum CitH3, cfDNA, and nucleosomes on Day 1 after ROSC showed a good predictive value for 28-day all-cause mortality.
Changes of Serum C-Reactive Protein Level in Patients With Depressive Disorders After Treatment With Agomelatine Combined With Aerobic Exercise and Its Significance
Authors: Sun Zhuping , Chen Silu , Zhang Hui , Gu Xiaoqing , Ge Haiyan , Chen Jinglei
Published: September 2023

Objective

Depressive disorders constitute a series of debilitating diseases. This study investigated the therapeutic effect of agomelatine (AG) combined with aerobic exercise (AE) on patients with moderate-severe depression (MSD) and the changes of the serum C-reactive protein (CRP) level in patients after treatment as well as its significance.

Methods

A total of 178 MSD patients were randomly assigned to the AG group (N = 90) and AG + AE group (N = 88). The severity of depressive disorders and anhedonia was assessed using the Hamilton Rating Scale for Depression (HAM-D), Beck Depression Inventory, and Snaith-Hamilton Pleasure Scale scores. The serum CRP level in MSD patients was detected by turbidity assay. Patients were defined as remitters, responders, and nonresponders according to the HAM-D17score, and the treatment efficacy was analyzed, followed by evaluation of the serum CRP level in patients with different treatment responses. Finally, the adverse reactions of patients during treatment were statistically analyzed.

Results

After treatment, the HAM-D, Beck Depression Inventory, and Snaith-Hamilton Pleasure Scale scores and the serum CRP level of the 2 groups were reduced, and changes in the AG + AE group was more significant than that in the AG group. The clinical efficacy of the AG + AE group was better than that of the AG group. After treatment, the serum levels of CRP in remitters and responders were reduced, but not significantly in nonresponders. The incidence of adverse events in the AG + AE group was lower than that in the AG group.

Conclusion

AG + AE reduced the serum level of CRP in MSD patients and had good therapeutic effects on MSD patients.
Burnout and Its Consequences among Vascular Surgeons and Trainees: A Danish National Survey
Authors: Møller Cecilie M , Clausen Thomas , Aust Birgit , Budtz-Lilly Jacob W , Eiberg Jonas P
Published: September 2023

Background:

Burnout among physicians has widespread negative consequences. Little is known about burnout among European vascular surgeons (VS). A previously published study found that 82% of VS and vascular surgical trainees (VST) in Denmark experience burnout symptoms. The present study aimed to investigate work- and health-related consequences of burnout.

Study Design:

An electronic survey was distributed to all VS/VST in Denmark in January 2020. Validated assessment tools were used to measure burnout, mental health and psychosocial work environment aspects.

Results:

Of 104 invited VS/VST, 82% (n=85) completed the survey. VS accounted for 72% (n=61) of the respondents, and 40% (n=33) were female. Statistically significant associations were found between higher levels of burnout and a range of work- and health-related outcomes, including a sense of meaning at work, workplace commitment, conflicts between work and private life, work stress, sick leave, and depressive symptoms. VS/VST using pain medication daily or weekly had significantly higher burnout scores than respondents who rarely or never use pain medication. A significant association between burnout and job satisfaction and retention was found, with respondents indicating an intention to stay within the specialty having significantly lower burnout scores than those who considered leaving within five years. Among those who indicated leaving the specialty, 35% (n=13) attributed this to their current working conditions.

Conclusion:

Burnout among VS/VST in Denmark is negatively associated with various work- and health-related outcomes. The work environment seems to play an essential role in these associations, and alterations workplace organization may remedy this situation.
Molecular interactions in short-chain perfluoroalkyl carboxylic acids and aqueous solutions
Authors: Benmore Chris J. , Wang Yuqin , Darling Seth B. , Chen Junhong
Published: September 2023

The presence of short-chain per- and polyfluoroalkyl substances in water poses a major health and environmental challenge. Here, we have performed high-energy small- and wide-angle X-ray scattering measurements on CF
3
[CF
2
]

n

COOH (where
n
 = 1, 2, 3 represents the chain length) and their aqueous solutions at 10% mole concentrations to characterize their molecular interactions at the atomic and nanometer length scales. The experimental wide-angle structure factors have been modelled using Empirical Potential Structural Refinement. The oxygen–oxygen partial X-ray pair distribution functions show that the coordination number between the hydroxyl oxygen on the acid and surrounding oxygen water molecules increases significantly with acid chain length, rising from 3.2 for
n
 = 1 to 4.1 for
n
 = 3. The small-angle scattering is dominated by a sharp, high-intensity peak at
Q
1
 ∼ 0.2 Å
−1
and a smaller peak at
Q
2 
= 1.2 Å
−1
for
n
 = 3, both of which decrease with decreasing chain length. The
Q
2
peak is attributed to groups of adjacent non-bonded acid molecules, and
Q
1
has contributions from both correlations between acid molecules and water–water interactions. In all cases, the models show nanoscale aggregation occurs in the form of denser channels of winding hydrogen-bonded chains, approximately 20 water molecules in length, surrounding clusters of acid molecules.

This article is part of the theme issue 'Exploring the length scales, timescales and chemistry of challenging materials (Part 2)'.
Methanol diffusion and dynamics in zeolite H-ZSM-5 probed by quasi-elastic neutron scattering and classical molecular dynamics simulations
Authors: Matam Santhosh K. , Silverwood Ian P. , Boudjema Lotfi , O'Malley Alexander J. , Catlow C. Richard A.
Published: September 2023

Zeolite ZSM-5 is a key catalyst in commercially relevant processes including the widely studied methanol to hydrocarbon reaction, and molecular diffusion in zeolite pores is known to be a crucial factor in controlling catalytic reactions. Here, we present critical analyses of recent quasi-elastic neutron scattering (QENS) data and complementary molecular dynamics (MD) simulations. The QENS experiments show that the nature of methanol diffusion dynamics in ZSM-5 pores is dependent both on the Si/Al ratio (11, 25, 36, 40 and 140), which determines the
Brønsted
acid site density of the zeolite, and that the nature of the type of motion observed may vary qualitatively over a relatively small temperature range. At 373 K, on increasing the ratio from 11 to 140, the observed mobile methanol fraction increases and the nature of methanol dynamics changes from rotational (in ZSM-5 with Si/Al of 11) to translational diffusion. The latter is either confined localized diffusion within a pore in zeolites with ratios up to 40 or non-localized, longer-range diffusion in zeolite samples with the ratio of 140. The complementary MD simulations conducted over long time scales (1 ns), which are longer than those measured in the present study by QENS (≈1–440 ps), at 373 K predict the occurrence of long-range translational diffusion of methanol in ZSM-5, independent of the Si/Al ratios (15, 47, 95, 191 and siliceous MFI). The rate of diffusion increases slightly by increasing the ratio from 15 to 95 and thereafter does not depend on zeolite composition. Discrepancies in the observed mobile methanol fraction between the MD simulations (100% methanol mobility in ZSM-5 pores across all Si/Al ratios) and QENS experiments (for example, ≈80% immobile methanol in ZSM-5 with Si/Al of 11) are attributed to the differences in time resolutions of the techniques. This perspective provides comprehensive information on the effect of acid site density on methanol dynamics in ZSM-5 pores and highlights the complementarity of QENS and MD, and their advantages and limitations.

This article is part of the theme issue ‘Exploring the length scales, timescales and chemistry of challenging materials (Part 2)’.
The local ordering of polar solvents around crystalline carbon nitride nanosheets in solution
Authors: Wilding Martin C. , Benmore Chris , Headen Thomas F. , Di Mino Camilla , Miller Thomas S. , Suter Theo M. , Corà Furio , Clancy Adam J. , Sella Andrea , McMillan Paul , Howard Christopher A.
Published: September 2023

The crystalline graphitic carbon nitride, poly-triazine imide (PTI) is highly unusual among layered materials since it is spontaneously soluble in aprotic, polar solvents including dimethylformamide (DMF). The PTI material consists of layers of carbon nitride intercalated with LiBr. When dissolved, the resulting solutions consist of dissolved, luminescent single to multilayer nanosheets of around 60–125 nm in diameter and Li+ and Br− ions originating from the intercalating salt. To understand this unique solubility, the structure of these solutions has been investigated by high-energy X-ray and neutron diffraction. Although the diffraction patterns are dominated by inter-solvent correlations there are clear differences between the X-ray diffraction data of the PTI solution and the solvent in the 4–6 Å
−1
range, with real space differences persisting to at least 10 Å. Structural modelling using both neutron and X-ray datasets as a constraint reveal the formation of distinct, dense solvation shells surrounding the nanoparticles with a layer of Br
−
close to the PTI-solvent interface. This solvent ordering provides a configuration that is energetically favourable underpinning thermodynamically driven PTI dissolution.

This article is part of the theme issue 'Exploring the length scales, timescales and chemistry of challenging materials (Part 2)'.
Nanomechanical properties of SSTSAA microcrystals are dominated by the inter-sheet packing
Authors: Meersman Filip , Quesada-Cabrera Raúl , Filinchuk Yaroslav , Dmitriev Vladimir , McMillan Paul F.
Published: September 2023

Amyloid fibrils have been associated with human disease for many decades, but it has also become apparent that they play a functional, non-disease-related role in e.g. bacteria and mammals. Moreover, they have been shown to possess interesting mechanical properties that can be harnessed for future man-made applications. Here, the mechanical behaviour of SSTSAA microcrystals has been investigated. The SSTSAA peptide organization in these microcrystals has been related to that in the corresponding amyloid fibrils. Using high-pressure X-ray diffraction experiments, the bulk modulus K, which is the reciprocal of the compressibility
β
, has been calculated to be 2.48 GPa. This indicates that the fibrils are tightly packed, although the packing of most native globular proteins is even better. It is shown that the value of the bulk modulus is mainly determined by the compression along the
c
-axis, that relates to the inter-sheet distance in the fibrils. These findings corroborate earlier data obtained by AFM and molecular dynamics simulations that showed that mechanical resistance varies according to the direction of the applied strain, which can be related to packing and hydrogen bond contributions. Pressure experiments provide complementary information to these techniques and help to acquire a full mechanical characterization of biomolecular assemblies.

This article is part of the theme issue ‘Exploring the length scales, timescales and chemistry of challenging materials (Part 2)’.
Photo-induced enhanced Raman spectroscopy as a probe for photocatalytic surfaces
Authors: Ben-Jaber Sultan , Glass Daniel , Brick Thomas , Maier Stefan A. , Parkin Ivan P. , Cortés Emiliano , Peveler William J. , Quesada-Cabrera Raúl
Published: September 2023

Photo-induced enhanced Raman spectroscopy (PIERS) has emerged as a highly sensitive surface-enhanced Raman spectroscopy (SERS) technique for the detection of ultra-low concentrations of organic molecules. The PIERS mechanism has been largely attributed to UV-induced formation of surface oxygen vacancies (V
o
) in semiconductor materials, although alternative interpretations have been suggested. Very recently, PIERS has been proposed as a surface probe for photocatalytic materials, following V
o
formation and healing kinetics. This work establishes comparison between PIERS and V
o
-induced SERS approaches in defected
noble-metal-free
titanium dioxide (TiO

2-
x

) films to further confirm the role of V
o
in PIERS. Upon application of three post-treatment methods (namely UV-induction, vacuum annealing and argon etching), correlation of V
o
kinetics and distribution could be established. A proposed mechanism and further discussion on PIERS as a probe to explore photocatalytic materials are also presented.

This article is part of the theme issue ‘Exploring the length scales, timescales and chemistry of challenging materials (Part 2)’.
Canyon Diablo lonsdaleite is a nanocomposite containing c/h stacking disordered diamond and diaphite
Authors: Németh Péter , Garvie Laurence A. J. , Salzmann Christoph G.
Published: September 2023

In 1967, a diamond polymorph was reported from hard, diamond-like grains of the Canyon Diablo iron meteorite and named lonsdaleite. This mineral was defined and identified by powder X-ray diffraction (XRD) features that were indexed with a hexagonal unit cell. Since 1967, several natural and synthetic diamond-like materials with XRD data matching lonsdaleite have been reported and the name lonsdaleite was used interchangeably with hexagonal diamond. Its hexagonal structure was speculated to lead to physical properties superior to cubic diamond, and as such has stimulated attempts to synthesize lonsdaleite. Despite numerous reports, several recent studies have provided alternative explanations for the XRD, transmission electron microscopy and Raman data used to identify lonsdaleite. Here, we show that lonsdaleite from the Canyon Diablo diamond-like grains are a nanocomposite material dominated by subnanometre-scale cubic/hexagonal stacking disordered diamond and diaphite domains. These nanostructured elements are intimately intergrown, giving rise to structural features erroneously associated with h diamond. Our data suggest that the diffuse scattering in XRD and the hexagonal features in transmission electron microscopy images reported from various natural and laboratory-prepared samples that were previously used for lonsdaleite identification, in fact arise from cubic/hexagonal stacking disordered diamond and diaphite domains.

This article is part of the theme issue 'Exploring the length scales, timescales and chemistry of challenging materials (Part 2)'.
Quantification of fragmentation capture materials and an assessment of the viability of economical alternatives: a preliminary study
Authors: Read James , Ritchie Thomas , Brown Laura , Bloodworth-Race Susie , Thawani Bonny , Critchley Richard , Hazael Rachael
Published: September 2023

High pressure, high-temperature events need to be quantified experimentally. Where fragmentation occurs, i.e. against personal protective equipment, there is a requirement for both a reliable and repeatable measurement of numerous experimental metrics. Typically, the most critical is calculating the energy absorbed by the target material, to characterize target performance. This is achieved by detonating a device and capturing a proportion of the fragmentation in a suitable material that can achieve successful recovery of all fragmentation produced. Therefore, allowing the estimation of the target's response using the depth of penetration within the capture material which allows the calculation of energy absorption. The current standardized fragmentation capture material used within the UK is known as strawboard. Although effective, this material is both expensive and limited in its availability. This study explores the classification of strawboard to provide a suitable baseline to compare against medium density fibreboard (MDF) and flooring underlay, which represent two more economically friendly alternatives on the openmarket. It was found that the uniformity of response for the MDF material was better than that of strawboard, due to its reproducibility between batches and velocity ranges. To further explore this phenomena, high explosive trials were conducted, further demonstrating MDF to be a viable, reliable and cheaper alternative.

This article is part of the theme issue 'Exploring the length scales, timescales and chemistry of challenging materials (Part 2)'.
Exploring the length scales, timescales and chemistry of challenging materials (Part 2)
Authors: Wilding Martin C. , Sella Andrea , Howard Christopher A. , Sobrido Ana Jorge , Catlow C. R. A.
Published: September 2023

This themed issue explores the different length and timescales that determine the physics and chemistry of a variety of key of materials, explored from the perspective of a wide range of disciplines, including physics, chemistry materials science, Earth science and biochemistry. The topics discussed include catalysis, chemistry under extreme conditions, energy materials, amorphous and liquid structure, hybrid organic materials and biological materials. The issue is in two parts, with this second set of contributions exploring hybrid organic materials, catalysis low-dimensional and graphitic materials, biological materials and naturally occurring, super-hard material as well as dynamic high pressure and new developments in imaging techniques pressure.

This article is part of the theme issue 'Exploring the length scales, timescales and chemistry of challenging materials (Part 2)'.
Exploring the Microbial Communities in Green Honey from Banggi Island, Sabah, Malaysia using Amplicon Sequencing Analysis
Authors: Ullah Saeed , Abdul Wahab Roswanira , Oyewusi Habeebat Adekilekun , Abdul Hamid Azzmer Azzar , Naim Mohamad Mohd Azrul , Huyop Fahrul
Published: September 2023

The green honey food product from honeybee is produced in the forest's subsurface region on Banggi Island, Because of its uniqueness, the product attracts a great market price. Naturally the honey doesn’t acquire microorganisms due to strong chemical property and dormant nature. Major causes of microbial contamination are probable to include pollen, the digestive tracts of honeybees, sources that are extremely difficult to control include earth, air, dust, and nectar. This study was carried out to determine the microbial diversity of green honey using amplicon sequencing method, we targeted 16S rRNA V3-V4 region for bacterial species and ITS1 region for fungal diversity. Result revolved that; Bacteria include the largest number of identified taxa (256) and read (136856400), total of (118) different bacteria species identified and validated with seven distinct phyla, namely protobacteria, Firmicutes, Actinobacteriota, Bacteriodata, fusobacteriota, chloroflexota, and some unclassified phylum. Among other identified species only 11 bacterial species relative abundance is higher than one percent. Fungi is the second largest with 08 taxa identified and number of read (16217100). Six different species of fungi and only two species of yeast were identified, all the identified species were belong to two different phyla Ascomycota and Basidiomycota. Among other identified genera genus Zygosaccharomyces have relative abundance (99%) as compared to other species identified, it reflects the very high abundance of Zygosaccharomyces in green honey sample.
High fusion and cytopathy of SARS-CoV-2 variant B.1.640.1
Authors: Bolland William , Michel Vincent , Planas Delphine , Hubert Mathieu , Guivel-Benhassine Florence , Porrot Françoise , Staropoli Isabelle , N’Debi Mélissa , Rodriguez Christophe , Fourati Slim , Prot Matthieu , Planchais Cyril , Hocqueloux Laurent , Simon-Lorière Etienne , Mouquet Hugo , Prazuck Thierry , Pawlotsky Jean-Michel , Bruel Timothée , Schwartz Olivier , Buchrieser Julian
Published: September 2023

SARS-CoV-2 variants with undetermined properties have emerged intermittently throughout the COVID-19 pandemic. Some variants possess unique phenotypes and mutations which allow further characterization of viral evolution and spike functions. Around 1100 cases of the B.1.640.1 variant were reported in Africa and Europe between 2021 and 2022, before the expansion of Omicron. Here, we analyzed the biological properties of a B.1.640.1 isolate and its spike. Compared to the ancestral spike, B.1.640.1 carried 14 amino acid substitutions and deletions. B.1.640.1 escaped binding by some anti-NTD and -RBD monoclonal antibodies, and neutralization by sera from convalescent and vaccinated individuals. In cell lines, infection generated large syncytia and a high cytopathic effect. In primary airway cells, B.1.640.1 replicated less than Omicron BA.1 and triggered more syncytia and cell death than other variants. The B.1.640.1 spike was highly fusogenic when expressed alone. This was mediated by two poorly characterized and infrequent mutations located in the spike S2 domain, T859N and D936H. Altogether, our results highlight the cytopathy of a hyper-fusogenic SARS-CoV-2 variant, supplanted upon the emergence of Omicron BA.1.

Importance

Our results highlight the plasticity of SARS-CoV-2 spike to generate highly fusogenic and cytopathic strains with the causative mutations being uncharacterized in previous variants. We describe mechanisms regulating the formation of syncytia and the subsequent consequences in cell lines and a primary culture model, which are poorly understood.