A metastable pentagonal 2D material synthesized by symmetry-driven epitaxy.

Most two-dimensional (2D) materials experimentally studied so far have hexagons as their building blocks. Only a few exceptions, such as PdSe2, are lower in energy in pentagonal phases and exhibit pentagons as building blocks. Although theory has predicted a large number of pentagonal 2D materials, many of these are metastable and their experimental realization is difficult. Here we report the successful synthesis of a metastable pentagonal 2D material, monolayer pentagonal PdTe2, by symmetry-driven epitaxy. Scanning tunnelling microscopy and complementary spectroscopy measurements are used to characterize this material, which demonstrates well-ordered low-symmetry atomic arrangements and is stabilized by lattice matching with the underlying Pd(100) substrate. Theoretical calculations, along with angle-resolved photoemission spectroscopy, reveal monolayer pentagonal PdTe2 to be a semiconductor with an indirect bandgap of 1.05 eV. Our work opens an avenue for the synthesis of pentagon-based 2D materials and gives opportunities to explore their applications such as multifunctional nanoelectronics.

Impact of reducing iodinated intravenous contrast volume in brain CT on image diagnostic quality.

PURPOSE: To investigate whether reducing the volume of intravenous iodinated contrast material injected during brain computed tomography (CT) provides reliable and accurate imaging without compromising diagnostic accuracy. METHODS: This prospective study enrolled patients undergoing enhanced brain CT at a single tertiary hospital. Subjects who agreed to participate received a reduced dose of 60 ml contrast. The images were compared to an age and gender-matched control group who received the conventional 80 cc dose. Neuroradiologists assessed image quality and interpretation using a 5-point Likert scale with six specific domains. Based on ICC, inter-rater reliability was high at 0.873. Multiple linear regression predicted overall diagnostic accuracy based on contrast dose, age, and gender. Visual Grading Characteristics (VGC) analysis was also performed to quantify regional brain enhancement differences between the two contrast groups. RESULTS: The study included 47 patients in the 60 cc group and 55 in the 80 cc control group. The results showed the 80 cc group had significantly higher enhancement ratings compared to 60 cc for all six structures assessed. The differences between groups ranged from -0.241 to -0.433 (p < 0.001) on the 5-point scale.The VGC analysis confirmed significantly greater brain parenchymal enhancement in the 80 cc group compared to the 60 cc group. CONCLUSION: The findings indicate that reducing the intravenous iodinated contrast material volume during brain CT from 80 cc to 60 cc leads to a statistically significant reduction in image quality and diagnostic accuracy. Further research with larger cohorts is needed to confirm these findings and assess the clinical impact of these differences.

Evaluating GenAI systems to combat mental health issues in healthcare workers: An integrative literature review.

BACKGROUND: Mental health issues among healthcare workers remain a serious problem globally. Recent surveys continue to report high levels of depression, anxiety, burnout and other conditions amongst various occupational groups. Novel approaches are needed to support clinician well-being. OBJECTIVE: This integrative literature review aims to explore the current state of research examining the use of generative artificial intelligence (GenAI) and machine learning (ML) systems to predict mental health issues and identify associated risk factors amongst healthcare professionals. METHODS: A literature search of databases was conducted in Medline then adapted as necessary to Scopus, Web of Science, Google Scholar, PubMed and CINAHL with Full Text. Eleven studies met the inclusion criteria for the review. RESULTS: Nine studies employed various machine learning techniques to predict different mental health outcomes among healthcare workers. Models showed good predictive performance, with AUCs ranging from 0.82 to 0.904 for outcomes such as depression, anxiety and safety perceptions. Key risk factors identified included fatigue, stress, burnout, workload, sleep issues and lack of support. Two studies explored the potential of sensor-based technologies and GenAI analysis of physiological data. None of the included studies focused on the use of GenAI systems specifically for providing mental health support to healthcare workers. CONCLUSION: Preliminary research demonstrates that AI/ML models can effectively predict mental health issues. However, more work is needed to evaluate the real-world integration and impact of these tools, including GenAI systems, in identifying clinician distress and supporting well-being over time. Further research should aim to explore how GenAI may be developed and applied to provide mental health support for healthcare workers.

The Effect of Neurodevelopmental Disorders Characteristics on Aspects of Social Functioning.

AIM: The purpose of this study was to estimate the extent to which neurodevelopmental disorders (NDD's) symptoms (motor, sensory, attention and executive function) are associated with aspects of social function among school aged children. METHODS: This cross-sectional study included 39 children aged 6-9 years old (71.8% boys) who were referred to child development centers due to motor, sensory, and/or cognitive difficulties. The parents completed NDD's symptoms questionnaires: Developmental Coordination Disorder Questionnaire; Child Sensory Profile-2; Attention Deficit Hyperactive Disorder (ADHD) Rating Scale and the Behavior Rating Inventory of Executive Function. They also completed the Social Skills Improvement System and a social participation measure. RESULTS: Analysis demonstrated low to moderate correlations between social functioning aspects and the majority of NDD's symptoms. Executive functioning was the only predictor of social skills and social participation and accounted for most of the variability of behavioral problems, alongside a small contribution of ADHD symptoms. CONCLUSION: The findings contribute to the accumulating body of knowledge regarding social abilities of children with NDD's and suggest new information as to the effect of executive functions in this domain. Along with conducting a routine evaluation of social skills among children suspected to have NDD's, executive functions should also be comprehensively evaluated.

Photoluminescence Induced by Substitutional Nitrogen in Single-Layer Tungsten Disulfide.

The electronic and optical properties of two-dimensional materials can be strongly influenced by defects, some of which can find significant implementations, such as controllable doping, prolonged valley lifetime, and single-photon emissions. In this work, we demonstrate that defects created by remote N2 plasma exposure in single-layer WS2 can induce a distinct low-energy photoluminescence (PL) peak at 1.59 eV, which is in sharp contrast to that caused by remote Ar plasma. This PL peak has a critical requirement on the N2 plasma exposure dose, which is strongest for WS2 with about 2.0% sulfur deficiencies (including substitutions and vacancies) and vanishes at 5.6% or higher sulfur deficiencies. Both experiments and first-principles calculations suggest that this 1.59 eV PL peak is caused by defects related to the sulfur substitutions by nitrogen, even though low-temperature PL measurements also reveal that not all the sulfur vacancies are remedied by the substitutional nitrogen. The distinct low-energy PL peak suggests that the substitutional nitrogen defect in single-layer WS2 can potentially serve as an isolated artificial atom for creating single-photon emitters, and its intensity can also be used to monitor the doping concentrations of substitutional nitrogen.

COVID-19 morbidity in an ethnic minority: changes during the first year of the pandemic.

OBJECTIVES: During the COVID-19 pandemic, ethnic minorities have been more susceptible to infection and demonstrated poorer outcomes. This study describes COVID-19 morbidity and mortality by ethnic group, represented by Arab and Jewish localities in Israel, during the different waves of the outbreak and addresses sociocultural aspects of the pandemic. STUDY DESIGN: A retrospective national archive study was conducted in Israel. METHODS: Data were obtained from the Ministry of Health's database, including daily information on Arab, Jewish or mixed localities, from February 2020 to February 2021. RESULTS: During the first wave of the pandemic, the incidence of COVID-19 in Arab compared with Jewish localities was 67% lower and mortality was 85% lower, in addition to lower rates of severe disease requiring hospitalisation. During the second and third waves, these trends reversed, with the proportion of positive tests, incidence and mortality in Arab localities reaching and then surpassing rates in Jewish localities. By September 2020, COVID-19 mortality was twice as high in Arab compared with Jewish localities. CONCLUSIONS: After low morbidity during the first wave of the COVID-19 pandemic, a surge in infections occurred in the Arab population during subsequent waves, to match and surpass the high incidence seen in the Jewish population. This unique pattern highlights the changing experiences of a minority group as the pandemic progressed and demonstrates how COVID-19 exacerbates existing disparities.

Evaluation of Artificial Intelligence-Powered Identification of Large-Vessel Occlusions in a Comprehensive Stroke Center.

BACKGROUND AND PURPOSE: Artificial intelligence algorithms have the potential to become an important diagnostic tool to optimize stroke workflow. Viz LVO is a medical product leveraging a convolutional neural network designed to detect large-vessel occlusions on CTA scans and notify the treatment team within minutes via a dedicated mobile application. We aimed to evaluate the detection accuracy of the Viz LVO in real clinical practice at a comprehensive stroke center. MATERIALS AND METHODS: Viz LVO was installed for this study in a comprehensive stroke center. All consecutive head and neck CTAs performed from January 2018 to March 2019 were scanned by the algorithm for detection of large-vessel occlusions. The system results were compared with the formal reports of senior neuroradiologists used as ground truth for the presence of a large-vessel occlusion. RESULTS: A total of 1167 CTAs were included in the study. Of these, 404 were stroke protocols. Seventy-five (6.4%) patients had a large-vessel occlusion as ground truth; 61 were detected by the system. Sensitivity was 0.81, negative predictive value was 0.99, and accuracy was 0.94. In the stroke protocol subgroup, 72 (17.8%) of 404 patients had a large-vessel occlusion, with 59 identified by the system, showing a sensitivity of 0.82, negative predictive value of 0.96, and accuracy of 0.89. CONCLUSIONS: Our experience evaluating Viz LVO shows that the system has the potential for early identification of patients with stroke with large-vessel occlusions, hopefully improving future management and stroke care.

A Library of Atomically Thin 2D Materials Featuring the Conductive-Point Resistive Switching Phenomenon.

Non-volatile resistive switching (NVRS) is a widely available effect in transitional metal oxides, colloquially known as memristors, and of broad interest for memory technology and neuromorphic computing. Until recently, NVRS was not known in other transitional metal dichalcogenides (TMDs), an important material class owing to their atomic thinness enabling the ultimate dimensional scaling. Here, various monolayer or few-layer 2D materials are presented in the conventional vertical structure that exhibit NVRS, including TMDs (MX2 , M = transitional metal, e.g., Mo, W, Re, Sn, or Pt; X = chalcogen, e.g., S, Se, or Te), TMD heterostructure (WS2 /MoS2 ), and an atomically thin insulator (h-BN). These results indicate the universality of the phenomenon in 2D non-conductive materials, and feature low switching voltage, large ON/OFF ratio, and forming-free characteristic. A dissociation-diffusion-adsorption model is proposed, attributing the enhanced conductance to metal atoms/ions adsorption into intrinsic vacancies, a conductive-point mechanism supported by first-principle calculations and scanning tunneling microscopy characterizations. The results motivate further research in the understanding and applications of defects in 2D materials.

Observation of single-defect memristor in an MoS2 atomic sheet.

Non-volatile resistive switching, also known as memristor1 effect, where an electric field switches the resistance states of a two-terminal device, has emerged as an important concept in the development of high-density information storage, computing and reconfigurable systems2-9. The past decade has witnessed substantial advances in non-volatile resistive switching materials such as metal oxides and solid electrolytes. It was long believed that leakage currents would prevent the observation of this phenomenon for nanometre-thin insulating layers. However, the recent discovery of non-volatile resistive switching in two-dimensional monolayers of transition metal dichalcogenide10,11 and hexagonal boron nitride12 sandwich structures (also known as atomristors) has refuted this belief and added a new materials dimension owing to the benefits of size scaling10,13. Here we elucidate the origin of the switching mechanism in atomic sheets using monolayer MoS2 as a model system. Atomistic imaging and spectroscopy reveal that metal substitution into a sulfur vacancy results in a non-volatile change in the resistance, which is corroborated by computational studies of defect structures and electronic states. These findings provide an atomistic understanding of non-volatile switching and open a new direction in precision defect engineering, down to a single defect, towards achieving the smallest memristor for applications in ultra-dense memory, neuromorphic computing and radio-frequency communication systems2,3,11.

Empathy, social relationship and co-occurrence in young adults with DCD.

Empathy is defined as an emotional or cognitive response to another's emotional state. It is considered essential for navigating meaningful social interactions and is closely linked to prosocial behavior. Developmental coordination disorder (DCD) is characterized by an impairment of motor coordination that has a marked impact on both academic and day-to-day living activities. Children and adolescents with DCD have been shown to have less developed social support and friendships. The research linking empathy and DCD is scarce. The aims of this study are to gain an understanding of the relationship between DCD and empathy in young adults with DCD only, and with DCD coupled with other neurodevelopmental disorders, in comparison with typically developing adults. METHODS: The study included 212 young adults aged 18-40 years. The subjects in this study were from mainstream populations in the UK. The study groups included: (a) "DCD only" with 42 individuals; (b) "DCD + ASD" with 21 individuals; (c) "DCD + ADHD" with 45 individuals; (d) "DCD + ASD + ADHD" with 29 individuals; and (e) the control group of 75 individuals. RESULTS: ANOVA on the Empathy Questionnaire (EQ) showed a statistically significant difference between groups (F [4,257] = 35.63; p < 0.001; ηp2 = 0.409). No significant differences were found between the DCD-only and the control. MANOVA was performed to assess differences in the Socialising and Friendship Questionnaire (SAF-Q) scores. The results showed a statistically significant difference between groups (F [8,257] = 9.98; p < 0.001; η = 0.162). Pearson correlation coefficients were performed, revealing significant high correlations between the EQ and the two parts of the SAF-Q ("past" and "currently"). CONCLUSION: The results of this study indicate that social difficulties in the DCD-only group are not due to lack of empathy, but may be driven by an accumulation of external factors. In this study we also concluded that DCD does not appear to be the factor that reduces the ability to empathize, but rather the presence of ADHD and/or ASD.

Emergency department mortality: Fair and square.

OBJECTIVE: This study explored the therapeutic approaches used for end-of-life (EOL) patients admitted to the emergency department (ED) and examined whether the decision to perform life-extending treatment (LET) or to allow natural death (AND) depends on patient characteristics, medical staff variables, and ED setting. METHODS: A retrospective archive study was conducted from January 2015 to December 2017 in the ED of a tertiary hospital. The study sample were 674 EOL patients who had died in the ED. For each patient, data were collected and measured for dying process (LET vs. AND), patient characteristics, ED-setting variables, and medical-staff characteristics. RESULTS: The proportion of EOL patients undergoing LET increased from 18.1% in 2015 to 25.9% in 2016 and to 30.3% in 2017 (p = .010), and a quarter of them were treated by emergency medical services. Males tended to receive LET more than females (p < .001). An association was found between Jewish physicians and nurses and AND (p = .001). Heavier workload in the ED and greater severity of the triage classification predicted more LET (OR-1.67, CI = 1.05-1.76, p = .003 and OR = 1.42, CI-0.60-0.81, p < .001, respectively). Receiver operating characteristic analysis showed that patient characteristics contributed most crucially to the therapeutic approaches (C statistic 0.624-0.675, CI-0.62-0.71). CONCLUSIONS: The therapeutic approach used for EOL patients in the ED depends on variables in all three treatment layers: patient, medical staff, and ED setting. Applicable national programs should be developed to ensure that no external factors influence the dying-process decision.

Detection of the Spin-Chemical Potential in Topological Insulators Using Spin-Polarized Four-Probe STM.

We demonstrate a new method for the detection of the spin-chemical potential in topological insulators using spin-polarized four-probe scanning tunneling microscopy on in situ cleaved Bi_{2}Te_{2}Se surfaces. Two-dimensional (2D) surface and 3D bulk conductions are separated quantitatively via variable probe-spacing measurements, enabling the isolation of the nonvanishing spin-dependent electrochemical potential from the Ohmic contribution. This component is identified as the spin-chemical potential arising from the 2D charge current through the spin momentum locked topological surface states (TSS). This method provides a direct measurement of spin current generation efficiency and opens a new avenue to access the intrinsic spin transport associated with pristine TSS.

Isoelectronic Tungsten Doping in Monolayer MoSe2 for Carrier Type Modulation.

Carrier-type modulation is demonstrated in 2D transition metal dichalcogenides as n-type monolayer MoSe2 is converted to nondegenerate p-type monolayer Mo1-x Wx Se2 through isoelectronic doping. Although the alloys are mesoscopically uniform, the p-type conduction in monolayer Mo1-x Wx Se2 appears to originate from the upshift of the valenceband maximum toward the Fermi level at highly localized "W-rich" regions in the lattice.

High-throughput electrical measurement and microfluidic sorting of semiconductor nanowires.

Existing nanowire electrical characterization tools not only are expensive and require sophisticated facilities, but are far too slow to enable statistical characterization of highly variable samples. They are also generally not compatible with further sorting and processing of nanowires. Here, we demonstrate a high-throughput, solution-based electro-orientation-spectroscopy (EOS) method, which is capable of automated electrical characterization of individual nanowires by direct optical visualization of their alignment behavior under spatially uniform electric fields of different frequencies. We demonstrate that EOS can quantitatively characterize the electrical conductivities of nanowires over a 6-order-of-magnitude range (10(-5) to 10 S m(-1), corresponding to typical carrier densities of 10(10)-10(16) cm(-3)), with different fluids used to suspend the nanowires. By implementing EOS in a simple microfluidic device, continuous electrical characterization is achieved, and the sorting of nanowires is demonstrated as a proof-of-concept. With measurement speeds two orders of magnitude faster than direct-contact methods, the automated EOS instrument enables for the first time the statistical characterization of highly variable 1D nanomaterials.

Differentiation of Surface and Bulk Conductivities in Topological Insulators via Four-Probe Spectroscopy.

We show a new method to differentiate conductivities from the surface states and the coexisting bulk states in topological insulators using a four-probe transport spectroscopy in a multiprobe scanning tunneling microscopy system. We derive a scaling relation of measured resistance with respect to varying interprobe spacing for two interconnected conduction channels to allow quantitative determination of conductivities from both channels. Using this method, we demonstrate the separation of 2D and 3D conduction in topological insulators by comparing the conductance scaling of Bi2Se3, Bi2Te2Se, and Sb-doped Bi2Se3 against a pure 2D conductance of graphene on SiC substrate. We also quantitatively show the effect of surface doping carriers on the 2D conductance enhancement in topological insulators. The method offers a means to understanding not just the topological insulators but also the 2D to 3D crossover of conductance in other complex systems.

Contactless Determination of Electrical Conductivity of One-Dimensional Nanomaterials by Solution-Based Electro-orientation Spectroscopy.

Nanowires of the same composition, and even fabricated within the same batch, often exhibit electrical conductivities that can vary by orders of magnitude. Unfortunately, existing electrical characterization methods are time-consuming, making the statistical survey of highly variable samples essentially impractical. Here, we demonstrate a contactless, solution-based method to efficiently measure the electrical conductivity of 1D nanomaterials based on their transient alignment behavior in ac electric fields of different frequencies. Comparison with direct transport measurements by probe-based scanning tunneling microscopy shows that electro-orientation spectroscopy can quantitatively measure nanowire conductivity over a 5-order-of-magnitude range, 10(-5)-1 Ω(-1) m(-1) (corresponding to resistivities in the range 10(2)-10(7) Ω·cm). With this method, we statistically characterize the conductivity of a variety of nanowires and find significant variability in silicon nanowires grown by metal-assisted chemical etching from the same wafer. We also find that the active carrier concentration of n-type silicon nanowires is greatly reduced by surface traps and that surface passivation increases the effective conductivity by an order of magnitude. This simple method makes electrical characterization of insulating and semiconducting 1D nanomaterials far more efficient and accessible to more researchers than current approaches. Electro-orientation spectroscopy also has the potential to be integrated with other solution-based methods for the high-throughput sorting and manipulation of 1D nanomaterials for postgrowth device assembly.

Hipofisitis linfocitaria: fisiopatología y utilidad de los anticuerpos antipituitarios para su diagnós / Lymphocytic Hypophysitis: Pathophysiology and Utility of Anti-Pituitary Antibodies for Diagnosis

La hipofisitis linfocitaria (HL) es un proceso autoinmune caracterizado por infiltración linfocitaria difusa de la glándula pituitaria con grados variables de destrucción. Los niveles elevados de prolactina y la caída de los estrógenos en el posparto son factores predisponentes para su desarrollo por lo que esta patología se presenta principalmente en mujeres jóvenes durante el embarazo o el puerperio. Se desconoce el antígeno implicado en su patogenia. En los últimos años se ha investigado la existencia de anticuerpos antipituitarios (APA) que permitan realizar un diagnóstico certero, de manera sencilla, con una sensibilidad y especificidad aceptables, que faciliten una adecuada interpretación clínica y un tratamiento acorde. Los autores declaran no poseer conflictos de interés.

Lymphocytic hypophysitis (HL) is an autoimmune condition characterized by diffuse lymphocytic infiltration of the pituitary gland with varying degrees of destruction. It occurs mainly in young women during pregnancy or the postpartum period secondary to elevated levels of prolactin (PRL) associated with a drop in estrogen levels in the postpartum period. The antigen involved in its pathogenesis is still unknown. In recent years, the existence of antipituitary antibodies (APA) has been investigated to allow a simple, accurate diagnosis, with acceptable sensitivity and specificity that enables an adequate clinical interpretation and treatment.

Relación entre circunferencia de cintura y factores de riesgo metabólicos en mujeres argentinas / Relationship Between Waist Circumference and Metabolic Risk Factors in Argentine Women

Introducción: El síndrome metabólico (SM) agrupa factores de riesgo para enfermedad cardiovascular. Dentro de estos factores se encuentra la obesidad central, evaluada generalmente a través de la circunferencia de la cintura (CC) Objetivo: Analizar el comportamiento de las distintas variables que agrupan el SM (definición ATP III) en relación a los cambios en la CC. Sujetos: Se incluyeron 253 mujeres que concurrieron al Servicio de Endocrinología. Se evaluaron medidas antropométricas y presión arterial, así como glucemia en ayunas y lipidograma. Las pacientes fueron agrupadas por quintilos por CC: Q1 (56-80 cm), Q2 (80.1-89 cm), Q3 (89.1-96 cm), Q4 (96.1-103 cm) y Q5 (103.1-150 cm. Resultados: Existe una correlación positiva entre la CC y el IMC (p < 0,0001, r: 0,87).Asimismo, se observa una correlación positiva entre la CC y los valores de triglicéridos (p <0,0001, r: 0,28), glucemia (p = 0,0001, r: 0,24), presión arterial (PA) sistólica (p < 0,0001, r: 0,27) y diastólica (p < 0,0007, r: 0,21) y una correlación negativa entre la CC y los niveles de HDL (p < 0,0001, r: -0,25). Conclusiones: A medida que aumenta la CC, aumentan los factores de riesgo cardiovasculares (presión arterial diastólica, glucemia, triglicéridos, descenso del HDL).

Introduction: Metabolic syndrome (MS) is a group of risk factors for cardiovascular disease. These factors include central obesity, usually assessed through waist circumference (WC). Objective: To analyze the behavior of the different MS variables (ATP III definition) in relation to changes in WC. Subjects: We included 253 women who attended the Service of Endocrinology. We performed anthropometric, blood pressure, fasting glucose and lipid profile measurements. Patients were grouped into quintiles by WC: Q1 (56-80 cm), Q2 (80.1-89 cm), Q3 (89.1-96 cm), Q4 (96.1-103 cm) and Q5 (103.1-150 cm. Results: There is a positive correlation between WC and BMI (p < 0.0001, r = 0.87). In addition, there is a positive correlation between WC and triglyceride levels (p < 0.0001, r: 0.28), glucose (p = 0.0001, r = 0.24), systolic blood pressure (BP) (p < 0.0001, r = 0.27) and diastolic BP (p <0.0007, r: 0.21) and a negative correlation between WC and HDL levels (p < 0.0001, r = -0.25). Conclusions: As WC increases, cardiovascular risk factors (diastolic blood pressure, blood glucose, triglycerides, decreased HDL) increase.

LPS-sensory peptide communication in experimental cystitis.

Stimulation of sensory nerves can lead to release of peptides such as substance P (SP) and consequently to neurogenic inflammation. We studied the role of bacterial lipopolysaccharide (LPS) in regulating SP-induced inflammation. Experimental cystitis was induced in female mice by intravesical instillation of SP, LPS, or fluorescein-labeled LPS. Uptake of fluorescein-labeled LPS was determined by confocal analysis, and bladder inflammation was determined by morphological analysis. SP was infused into the bladders of some mice 24 h after exposure to LPS. In vitro studies determined the capacity of LPS and SP to induce histamine and cytokine release by the bladder. LPS was taken up by urothelial cells and distributed systemically. Twenty-four hours after instillation of LPS or SP, bladder inflammation was characterized by edema and leukocytic infiltration of the bladder wall. LPS pretreatment enhanced neutrophil infiltration induced by SP, increased in vitro release of histamine, tumor necrosis factor-alpha, and interferon-gamma, and significantly reduced transforming growth factor-beta1 release. These findings suggest that LPS amplifies neurogenic inflammation, thereby playing a role in the pathogenesis of neurogenic cystitis.