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BACKGROUND: Manganese (Mn) plays a significant role in both human health and global industries. Epidemiological studies of exposed populations demonstrate a dose-dependent association between Mn and neuromotor effects ranging from subclinical effects to a clinically defined syndrome. However, little is known about the relationship between early life Mn biomarkers and adolescent postural balance. OBJECTIVES: This study investigated the associations between childhood and adolescent Mn biomarkers and adolescent postural balance in participants from the longitudinal Marietta Communities Actively Researching Exposures Study (CARES) cohort. METHODS: Participants were recruited into CARES when they were 7-9 y old, and reenrolled at 13-18 years of age. At both time points, participants provided samples of blood, hair, and toenails that were analyzed for blood Mn and lead (Pb), serum cotinine, hair Mn, and toenail Mn. In adolescence, participants completed a postural balance assessment. Greater sway indicates postural instability (harmful effect), whereas lesser sway indicates postural stability (beneficial effect). Multivariable linear regression models were conducted to investigate the associations between childhood and adolescent Mn biomarkers and adolescent postural balance adjusted for age, sex, height--weight ratio, parent/caregiver intelligence quotient, socioeconomic status, blood Pb, and serum cotinine. RESULTS: CARES participants who completed the adolescent postural balance assessment (n=123) were 98% White and 54% female and had a mean age of 16 y (range: 13-18 y). In both childhood and adolescence, higher Mn biomarker concentrations were significantly associated with greater adolescent sway measures. Supplemental analyses revealed sex-specific associations; higher childhood Mn biomarker concentrations were significantly associated with greater sway in females compared with males. DISCUSSION: This study found childhood and adolescent Mn biomarkers were associated with subclinical neuromotor effects in adolescence. This study demonstrates postural balance as a sensitive measure to assess the association between Mn biomarkers and neuromotor function. https://doi.org/10.1289/EHP13381, Introduction Manganese (Mn) is an element that exists ubiquitously in the environment, often in combination with other elements. (1) Mn plays a significant role in both human health and global [...]

Germanium substitution in the well-known photovoltaic material Cu2ZnSnS4 has been previously shown to improve power conversion efficiencies, but detailed information about the local structure within solid solutions Cu2ZnSn1−xGexS4 has so far been lacking. Given the many ways the metal cations can be distributed, several structural models for the site distribution are possible. In conjunction with powder X-ray diffraction, multinuclear magnetic resonance spectroscopy (63/65Cu, 67Zn, 73Ge, and 119Sn) was applied to evaluate these models because these nuclei are sensitive to variations in the coordination environments around specific atoms. The 67Zn NMR spectra indicate that Zn atoms are in lower symmetry environments in Cu2ZnGeS4 than in Cu2ZnSnS4, as their different quadrupole coupling constants suggested. The 73Ge and 119Sn NMR spectra show gradual changes in chemical shift, indicating that Ge and Sn atoms are randomly mixed in tetrahedral sites within the entire range of solid solubility. The 63/65Cu NMR spectra collected at high field (21.1 T) reveal two distinct Cu sites for all members of Cu2ZnSn1−xGexS4, consistent with the structure model in space group I4¯, as also supported by DFT calculations of NMR parameters. Ge substitution increases the experimental band gap from 1.5 eV in Cu2ZnSnS4 to 2.0 eV in Cu2ZnGeS4 because the conduction band minimum is raised to higher energy, as shown by electronic structure calculations. [ABSTRACT FROM AUTHOR]

In this interview, Bangladeshi Anglophone poet, translator, and critic Kaiser Haq discusses diverse aspects of his writings and concerns. First of all, he talks about his recently published poetry collection, The New Frontier & Other Odds and Ends in Verse and Prose. Then, he dwells upon the charms and challenges of conquering new frontiers during his long poetic journey, his distinguished career as an academician, his role as an essayist and his work as a translator. He gives his opinion about the tradition of Bangladeshi Anglophone poetry and sheds light on his stance as a poet-witness and as a social critic. His representation of aberrant figures, debt to Bengal's rich folk heritage, transformation of mundane observations to socio-political musings, and exploration of issues like identity and the environment come to the fore in course of the conversation. He spells out his poetic standpoint on issues like tradition and modernity, love and sex, religion and ethnicity, and diversity and unity. He takes pains to explain how his poetry testifies to Bangladesh's evolution over the years through all the ups and downs. He points out how exposure to other climes and cultures and love for his own country and country people complement each other to create his poetic credo. Later, he elaborates on his attitude to memory and the media. He reveals his perspectives on poetic craftmanship and stylistic innovation. The interview wraps up with an enduring message from Kaiser Haq the poet for his readers. [ABSTRACT FROM AUTHOR]

Global fire activities, which are getting worse due to climate change, cause both environmental and human health hazards. Firefighters, being the first responders, are frequently exposed to heat which may impact their immune system and overall health. However, the nature of the impact of chronic heat exposure on immune function has not been studied in-depth in firefighters. In this study, 22 firefighters exposed to "heavy-smoke fires (structural fires)", categorized as the "high-exposure group" (>0.15 structural fires/week) and "low-exposure group" (<0.15 structural fires/week), were sampled. Peripheral blood was examined for immune cell profile based on total and differential cell counts, immune function based on the transcriptional expression of drivers of innate and adaptive immunity and key inflammation mediators, and heat stress marker HSP70. The white blood cell (WBC) count, mean corpuscular volume, mean corpuscular hemoglobin, and absolute and segmented neutrophil counts decreased below the normal range in both exposure groups. The gene transcript levels for toll-like receptors (TLR2, TLR4, but not TLR7) and their adaptor protein MYD88 were lower whereas those for T-cell transcription factors (RORC/RORγ, FoxP3) and inflammatory mediators (TNF-α, Granzyme-B) were higher in the "high-exposure group", indicating mixed response; however, the ratios between pro-inflammatory and anti-inflammatory transcription factors of adaptive immunity, namely T-bet/FoxP3 (Th1/Treg) and RORC/FoxP3 (Th17/Treg), were lower. Collectively, decreased immune cell landscape, downregulated key innate immunity receptors, and Tregs' dominance suggested that chronic heat exposure in firefighters dysregulated innate and adaptive immunity, skewed towards an overall immunosuppressive condition with inflammation. [ABSTRACT FROM AUTHOR]

Objectives: Schizophrenia is a persistent and incapacitating psychiatric condition characterized by symptoms with positive, negative, affective, and cognitive domains. Sleep disturbances represent an important facet of this disorder, impacting both the quality of life and influencing its overall outcome. In the cross-sectional study, we intended to investigate the polysomnographic findings of patients with schizophrenia showing predominantly positive symptoms as opposed to those presenting with predominantly negative symptoms and also as compared to normal population. Methods: This study had a cross-sectional design, involving the recruitment of 60 medication-naive patients diagnosed with schizophrenia according to the ICD-10 criteria and 30 study participants representing normal population. The cases were subdivided into two groups: one characterized by predominantly positive symptoms and the other characterized by predominantly negative symptoms. Both the groups received overnight polysomnography, and study variables were recorded. Results: All the sleep parameters were deranged in patients with schizophrenia as compared to normal controls in the general population, with significantly more pronounced differences found in those with predominant positive symptoms for most variables (p < 0.001). The only exception was the duration of N3 (slow-wave sleep) which was significantly decreased in patients with negative symptoms compared to those with positive symptoms (p < 0.001). But no significant differences were found between the negative and positive symptom domain groups in mean rapid eye movement (REM) latency, duration of N1 and N2 sleep, and total percentage of REM sleep. Conclusion: This study highlights substantial variations in sleep patterns between the negative and positive symptom domains of schizophrenia and also as compared to the general population. Further study is imperative to explore the link between circadian integrity and symptoms of the various domains of schizophrenia. [ABSTRACT FROM AUTHOR]

Objectives. Postural imbalance can result from hyperthermia-mediated muscular fatigue and is a major factor contributing to injuries from falling. The objective of this study was to investigate the effect of exercise-induced hyperthermia and the impact of cooling on postural balance while wearing fire-fighters' protective clothing (FPC) in a hot environment. Methods. A portable force platform measured postural balance characterized by postural sway patterns using center of pressure metrics. Twelve healthy, physically fit males were recruited to stand on the force platform once with eyes open and once with eyes closed before and after treadmill exercise (40% ...O2max) inside an environmental chamber under hot and humid conditions (30 °C and 70% relative humidity) while wearing FPC. Subjects participated in two randomly assigned experimental phases: control and cooling intervention. Results. A significant increase in physiological responses and postural balance metrics was observed after exercising in the heat chamber while wearing FPC. Cooling resulted in a significant effect only on postural sway speed after exercise-induced hyperthermia. Conclusions. Hyperthermia can negatively alter postural balance metrics, which may lead to an increased likelihood of falling. The utilization of body cooling reduced the thermal strain but had limited impact on postural balance stability. [ABSTRACT FROM AUTHOR]

Introduction: Schizophrenia is a severe mental disorder characterised by positive symptoms such as delusions and hallucinations, as well as negative symptoms including anhedonia, asociality, avolition, and affective blunting. It may also be associated with cognitive deficits. Sleep disturbances are commonly encountered in schizophrenia, and there may be variations in sleep patterns among its different subtypes. These differences in sleep patterns could have prognostic implications for the various subtypes of schizophrenia. Effective management of sleep disturbances could contribute to the recovery and wellbeing of individuals diagnosed with schizophrenia. Aim: To compare the differences in sleep architecture between the various subtypes of schizophrenia and to compare them with socio-demographically matched healthy volunteers. Materials and Methods: A cross-sectional study was conducted at the Institute of Psychiatry-Centre of Excellence, Kolkata, West Bengal, India over a duration of one year (May 2016 to June 2017). The study included 60 medication-naïve patients diagnosed with schizophrenia according to International Classification of Diseases (ICD)-10 criteria, and a control group of 30 demographically matched healthy volunteers. All study participants were aged between 18 and 60 years and free from any co-morbid illnesses. Patients with schizophrenia were further classified into four groups based on the ICD-10 subtypes: paranoid, hebephrenic, catatonic, and undifferentiated. Overnight polysomnography was performed to assess sleep parameters, including total record time, total sleep time, sleep onset latency, Rapid Eye Movement (REM), sleep latency, sleep efficiency, durations of Total Non Rapid Eye Movement (NREM) Sleep, Total REM sleep, and the different phases of NREM sleep. Statistical analysis was performed using Statistical Package for the Social Sciences (SPSS) version 20.0. Analysis of Variance (ANOVA), Chi-square, and t-test were used as applicable, with a p-value <0.05 considered statistically significant. Results: The results showed a decrease in sleep efficiency, total sleep time, and shorter duration of mean N1, N2, and N3 sleep in schizophrenia patients compared to the control group. There was a significant difference in N3 sleep duration, reduced duration of total NREM and REM sleep, reduced REM latency, increased sleep onset latency, and the number of awakenings during sleep in schizophrenia patients. Statistically significant differences (p-values <0.05) were also noted in some sleep parameters among the various subtypes of schizophrenia. The paranoid subtype had the shortest REM latency, while the catatonic subtype had the longest. The hebephrenic subtype had the lowest percentage of REM sleep and sleep efficiency, while the catatonic subtype had the highest. The duration of Slow Wave Sleep (SWS) was lowest in the undifferentiated subtype and highest in the catatonic subtype. Conclusion: This study reveals significant differences in sleep patterns between patients with schizophrenia and the control group, as well as among the various subtypes of schizophrenia. These distinctions provide insight into the relationship between schizophrenia subtypes, sleep irregularities, and clinical consequences. Further investigation is necessary to explore differences in sleep architecture among the various subtypes of schizophrenia and yield clinically meaningful results. [ABSTRACT FROM AUTHOR]

Aliovalent substitution of the B component in ABX3 metal halides has often been proposed to modify the band gap and thus the photovoltaic properties, but details about the resulting structure have remained largely unknown. Here, we examine these effects in Bi-substituted CsSnBr3. Powder X-ray diffraction (XRD) and solid-state 119Sn, 133Cs and 209Bi nuclear magnetic resonance (NMR) spectroscopy were carried out to infer how Bi substitution changes the structure of these compounds. The cubic perovskite structure is preserved upon Bi-substitution, but with disorder in the B site occurring at the atomic level. Bi atoms are randomly distributed as they substitute for Sn atoms with no evidence of Bi segregation. The absorption edge in the optical spectra shifts from 1.8 to 1.2 eV upon Bi-substitution, maintaining a direct band gap according to electronic structure calculations. It is shown that Bi-substitution improves resistance to degradation by inhibiting the oxidation of Sn. All-inorganic lead-free halide perovskites are highly promising photovoltaic materials, but higher-valent substitution of the divalent metal in such structures is poorly investigated. Here, the authors study the effects of substituting tin with bismuth in CsSnBr3 and find that the parent perovskite structure is preserved, while the absorption edge shifts, and degradation resistance is increased. [ABSTRACT FROM AUTHOR]