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Heavy-fermion metals are prototype systems for observing emergent quantum phases driven by electronic interactions1-6. A long-standing aspiration is the dimensional reduction of these materials to exert control over their quantum phases7-11, which remains a significant challenge because traditional intermetallic heavy-fermion compounds have three-dimensional atomic and electronic structures. Here we report comprehensive thermodynamic and spectroscopic evidence of an antiferromagnetically ordered heavy-fermion ground state in CeSiI, an intermetallic comprising two-dimensional (2D) metallic sheets held together by weak interlayer van der Waals (vdW) interactions. Owing to its vdW nature, CeSiI has a quasi-2D electronic structure, and we can control its physical dimension through exfoliation. The emergence of coherent hybridization of f and conduction electrons at low temperature is supported by the temperature evolution of angle-resolved photoemission and scanning tunnelling spectra near the Fermi level and by heat capacity measurements. Electrical transport measurements on few-layer flakes reveal heavy-fermion behaviour and magnetic order down to the ultra-thin regime. Our work establishes CeSiI and related materials as a unique platform for studying dimensionally confined heavy fermions in bulk crystals and employing 2D device fabrication techniques and vdW heterostructures12 to manipulate the interplay between Kondo screening, magnetic order and proximity effects.
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BACKGROUND: During a COVID-19 pandemic, it is imperative to investigate the outcomes of all non-COVID-19 diseases. This study determines hospital admissions and mortality rates related to non-COVID-19 diseases during the COVID-19 pandemic among 41 million Iranians. METHOD: This nationwide retrospective study used data from the Iran Health Insurance Organization. From September 23, 2019, to Feb 19, 2022, there were four study periods: pre-pandemic (Sept 23-Feb 19, 2020), first peak (Mar 20-Apr 19, 2020), first year (Feb 20, 2020-Feb 18, 2021), and the second year (Feb 19, 2021-Feb 19, 2022) following the pandemic. Cause-specific hospital admission and in-hospital mortality are the main outcomes analyzed based on age and sex. Negative binomial regression was used to estimate the monthly adjusted Incidence Rate Ratio (IRR) to compare hospital admission rates in aggregated data. A logistic regression was used to estimate the monthly adjusted in-hospital mortality Odds Ratio (OR) for different pandemic periods. RESULTS: During the study there were 6,522,114 non-COVID-19 hospital admissions and 139,679 deaths. Prior to the COVID-19 outbreak, the standardized hospital admission rate per million person-month was 7115.19, which decreased to 2856.35 during the first peak (IRR 0.40, [0.25-0.64]). In-hospital mortality also increased from 20.20 to 31.99 (OR 2.05, [1.97-2.13]). All age and sex groups had decreased admission rates, except for females at productive ages. Two years after the COVID-19 outbreak, the non-COVID-19 hospital admission rate (IRR 1.25, [1.13-1.40]) and mortality rate (OR 1.05, [1.04-1.07]) increased compared to the rates before the pandemic. The respiratory disease admission rate decreased in the first (IRR 0.23, [0.17-0.31]) and second years (IRR 0.35, [0.26-0.47] compared to the rate before the pandemic. There was a significant reduction in hospitalizations for pneumonia (IRR 0.30, [0.21-0.42]), influenza (IRR 0.04, [0.03-0.06]) and COPD (IRR 0.39, [0.23-0.65]) during the second year. There was a significant and continuous rise in the hematological admission rate during the study, reaching 186.99 per million person-month in the second year, reflecting an IRR of 2.84 [2.42-3.33] compared to the pre-pandemic period. The mortality rates of mental disorders (OR 2.15, [1.65-2.78]) and musculoskeletal (OR 1.48, [1.20-1.82), nervous system (OR 1.42, [1.26-1.60]), metabolic (OR 1.99, [1.80-2.19]) and circulatory diseases (OR 1.35, [1.31-1.39]) increased in the second year compare to pre-pandemic. Myocardial infarction (OR 1.33, [1.19-1.49]), heart failure (OR 1.59, [1.35-1.87]) and stroke (OR 1.35, [1.24-1.47]) showed an increase in mortality rates without changes in hospitalization. CONCLUSIONS: In the era of COVID-19, the changes seem to have had a long-term effect on non-COVID-19 diseases. Countries should prepare for similar crises in the future to ensure medical services are not suspended.
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COVID-19 , Hospitalización , Mortalidad , Femenino , Humanos , COVID-19/epidemiología , Hospitalización/estadística & datos numéricos , Irán/epidemiología , Pueblos de Medio Oriente/estadística & datos numéricos , Infarto del Miocardio/epidemiología , Pandemias/estadística & datos numéricos , Estudios Retrospectivos , Estudios Longitudinales , Mortalidad/tendencias , MasculinoRESUMEN
Head computed tomography (CT) is the preferred imaging modality for mild traumatic brain injury (mTBI). The routine use of head CT in low-risk individuals with mild TBI offers no clinical benefit but also causes notable health and financial burden. Despite the availability of related guidelines, studies have reported considerable rate of non-indicated head CT requests. The objectives were to provide an overall estimate for the head CT overutilization rate and to identify the factors contributing to the overuse. A systematic review of PubMed, Scopus, Web of Science, and Embase databases was conducted up to November 2023, following PRISMA and MOOSE guidelines. Two reviewers independently selected eligible articles and extracted data. Quality assessment was performed using a bias risk tool, and a random-effects model was used for data synthesis. Fourteen studies, encompassing 28,612 patients, were included, with 27,809 undergoing head CT scans. Notably, 75% of the included studies exhibited a moderate to high risk of bias. The overutilization rate for pediatric and adult patients was 27% (95% CI: 5-50%) and 32% (95% CI: 21-44%), respectively. An alternative rate, focusing on low-risk pediatric patients, was 54% (95% CI: 20-89%). Overutilization rates showed no significant difference between teaching and non-teaching hospitals. Patients with mTBI from falls or assaults were less likely to receive non-indicated scans. There was no significant association between physician specialty or seniority and overuse, nor between patients' age or sex and the likelihood of receiving a non-indicated scan. Approximately one-third of head CT scans in mTBI cases are avoidable, underscoring the necessity for quality improvement programs to reduce unnecessary imaging and its associated burdens.
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Conmoción Encefálica , Tomografía Computarizada por Rayos X , Humanos , Conmoción Encefálica/diagnóstico por imagenRESUMEN
OBJECTIVE: Pain often accompanies carpal tunnel syndrome and affects patients' health-related quality of life. The aim was to develop and validate a predictive model for the pain intensity of carpal tunnel syndrome using demographic, clinical, electrophysiological, and ultrasound findings. METHODS: We conducted a secondary analysis of data from a large sample of patients (May 2017 to December 2022) with carpal tunnel syndrome. A total of 520 (53.0â¯%) mild, 276 (28.1â¯%) moderate, and 186 (18.9â¯%) severe syndromes were included in the complete data set of 982 hands (61.1â¯% female). The mean age was 57.8 (10.7) years and the median duration [interquartile range] of the symptoms was 4 [2,10] months. A regression model was developed and validated to predict pain intensity on a numerical rating scale using a tree-based machine learning algorithm. RESULTS: The validation of the regression model showed good performance with a root mean squared error, R-squared, and mean absolute error of 1.35, 0.42, and 1.05, respectively. Overall, the top significant predictors of pain intensity were compound motor nerve action potential latency, nocturnal pain, and thenar weakness. These were followed by the cross-sectional area of the median nerve, sensory nerve action potential, bowing of the flexor retinaculum, disease duration, and body mass index. We did not find strong associations between the median nerve transcarpal latency, age, sex, and diabetes with the pain intensity of carpal tunnel syndrome. CONCLUSION: Our model showed good performance in predicting the subjective pain intensity of carpal tunnel syndrome, even in the context of non-linear relations.
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Síndrome del Túnel Carpiano , Dimensión del Dolor , Humanos , Síndrome del Túnel Carpiano/fisiopatología , Femenino , Persona de Mediana Edad , Masculino , Anciano , Dimensión del Dolor/métodos , Adulto , Dolor/fisiopatología , Dolor/etiologíaRESUMEN
OBJECTIVES: Metastatic prostate cancer is the most common malignant cancer and the second leading cause of death due to various types of cancer among men after lung cancer. This study aimed to analyze the cost-effectiveness of triptorelin, goserelin, and leuprolide in the treatment of the patients with metastatic prostate cancer from the societal perspective in Iran in 2020. METHODS: This is a cost-effectiveness study in which a 20-year Markov transition modeling was applied. In this study, local cost and quality-of-life data of each health state were gathered from cohort of patients. The TreeAge pro 2020 and Microsoft Excel 2016 software were used to simulate cost-effectiveness of each treatment in the long term. The one-way and probabilistic sensitivity analyses were also performed to measure robustness of the model outputs. RESULTS: The findings indicated that the mean costs and utility gained over a 20-year horizon for goserelin, triptorelin, and leuprolide treatments were $ 13 539.13 and 6.365 quality-adjusted life-years (QALY), $ 18 124.75 and 6.658 QALY, and $ 26 006.92 and 6.856 QALY, respectively. Goserelin was considered as a superior treatment option, given the estimated incremental cost-effectiveness ratio. The one-way and probabilistic sensitivity analyses confirmed the robustness of the study outcomes. CONCLUSIONS: According to the results of the present study, goserelin was the most effective and cost-effective strategy versus 2 other options. It could be recommended to policy makers of the Iran healthcare system to prioritize it in clinical guidelines and reimbursement policies.
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Antineoplásicos Hormonales , Goserelina , Leuprolida , Neoplasias de la Próstata , Años de Vida Ajustados por Calidad de Vida , Pamoato de Triptorelina , Anciano , Humanos , Masculino , Persona de Mediana Edad , Antineoplásicos Hormonales/uso terapéutico , Antineoplásicos Hormonales/economía , Análisis de Costo-Efectividad , Goserelina/uso terapéutico , Goserelina/economía , Goserelina/administración & dosificación , Irán , Leuprolida/uso terapéutico , Leuprolida/economía , Leuprolida/administración & dosificación , Cadenas de Markov , Metástasis de la Neoplasia , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/economía , Calidad de Vida , Pamoato de Triptorelina/uso terapéutico , Pamoato de Triptorelina/economía , Pamoato de Triptorelina/administración & dosificaciónRESUMEN
Neurological disorders are a heterogeneous group of central or peripheral nervous disorders of which the main symptoms include impaired walking and balance. One of the main interventions for neurological disorders is the use of assistive devices, and it is necessary to consider the psychosocial effects of these devices on users. The psychometric properties of the Persian version of the Psychosocial Impact of Assistive Devices Scale (PIADS) were evaluated in patients with neurological disorders. After translating the scale into Persian based on IQULA, face and content validity were determined. The divergent validity of the scale was examined through its relationship with the Orthotics and Prosthetics Users' Survey (OPUS). Reliability of the tool was evaluated using an internal consistency and test-retest method over two weeks with 50 patients with neurological disorders and a history of using assistive devices for at least six months. The face and content validity of the PIADS was confirmed. The ICC for all subscales was higher than 0.78, which indicates a good correlation. However, the divergent validity of the scale with the OPUS scale was not confirmed. The Persian version of PIADS is a valid and reliable measure for patients with neurological disorders in Iran.
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BACKGROUND: Different populations and areas of the world experienced diverse COVID-19 hospitalization and mortality rates. Claims data is a systematically recorded source of hospitalized patients' information that could be used to evaluate the disease management course and outcomes. We aimed to investigate the hospitalization and mortality patterns and associated factors in a huge sample of hospitalized patients. METHODS: In this retrospective registry-based study, we utilized claim data from the Iran Health Insurance Organization (IHIO) consisting of approximately one million hospitalized patients across various hospitals in Iran over a 26-month period. All records in the hospitalization dataset with ICD-10 codes U07.1/U07.2 for clinically/laboratory confirmed COVID-19 were included. In this study, a case referred to one instance of a patient being hospitalized. If a patient experienced multiple hospitalizations within 30 days, those were aggregated into a single case. However, if hospitalizations had longer intervals, they were considered independent cases. The primary outcomes of study were general and intensive care unit (ICU) hospitalization periods and case fatality rate (CFR) at the hospital. Besides, various demographic and hospitalization-associated factors were analyzed to derive the associations with study outcomes using accelerated failure time (AFT) and logistic regression models. RESULTS: A total number of 1 113 678 admissions with COVID-19 diagnosis were recorded by IHIO during the study period, defined as 917 198 cases, including 51.9% females and 48.1% males. The 61-70 age group had the highest number of cases for both sexes. Among defined cases, CFR was 10.36% (95% CI: 10.29-10.42). The >80 age group had the highest CFR (26.01% [95% CI: 25.75-26.27]). The median of overall hospitalization and ICU days were 4 (IQR: 3-7) and 5 (IQR: 2-8), respectively. Male patients had a significantly higher risk for mortality both generally (odds ratio (OR) = 1.36 [1.34-1.37]) and among ICU admitted patients (1.12 [1.09-1.12]). Among various insurance funds, Foreign Citizens had the highest risk of death both generally (adjusted OR = 2.06 [1.91-2.22]) and in ICU (aOR = 1.71 [1.51-1.92]). Increasing age groups was a risk of longer hospitalization, and the >80 age group had the highest risk for overall hospitalization period (median ratio = 1.52 [1.51-1.54]) and at ICU (median ratio = 1.17 [1.16-1.18]). Considering Tehran as the reference province, Sistan and Balcuchestan (aOR = 1.4 [1.32-1.48]), Alborz (aOR = 1.28 [1.22-1.35]), and Khorasan Razavi (aOR = 1.24 [1.20-1.28]) were the provinces with the highest risk of mortality in hospitalized patients. CONCLUSION: Hospitalization data unveiled mortality and duration associations with variables, highlighting provincial outcome disparities in Iran. Using enhanced registry systems in conjunction with other studies, empowers policymakers with evidence for optimizing resource allocation and fortifying healthcare system resilience against future health challenges.