The role of collisional ionization in heavy ion acceleration by high intensity laser pulses.

We present here simulation results of the laser-driven acceleration of gold ions using the EPOCH code. Recently, an experiment reported the acceleration of gold ions up to 7 MeV/nucleon with a strong dependency of the charge-state distribution on target thickness and the detection of the highest charge states [Formula: see text]. Our simulations using a developmental branch of EPOCH (4.18-Ionization) show that collisional ionization is the most important cause of charge states beyond Z = 51 up to He-like Au.

Real-Time Electron Solvation Induced by Bursts of Laser-Accelerated Protons in Liquid Water.

Understanding the mechanisms of proton energy deposition in matter and subsequent damage formation is fundamental to radiation science. Here we exploit the picosecond (10^{-12} s) resolution of laser-driven accelerators to track ultrafast solvation dynamics for electrons due to proton radiolysis in liquid water (H_{2}O). Comparing these results with modeling that assumes initial conditions similar to those found in photolysis reveals that solvation time due to protons is extended by >20 ps. Supported by magnetohydrodynamic theory this indicates a highly dynamic phase in the immediate aftermath of the proton interaction that is not accounted for in current models.

Wavelet threshold based on Stein's unbiased risk estimators of restricted location parameter in multivariate normal.

In this paper, the problem of estimating the mean vector under non-negative constraints on location vector of the multivariate normal distribution is investigated. The value of the wavelet threshold based on Stein's unbiased risk estimators is calculated for the shrinkage estimator in restricted parameter space. We suppose that covariance matrix is unknown and we find the dominant class of shrinkage estimators under Balance loss function. The performance evaluation of the proposed class of estimators is checked through a simulation study by using risk and average mean square error values.

Relationship between blood group and risk of infection and death in COVID-19: a live meta-analysis.

The relationship between ABO blood group and the incidence of coronavirus disease 2019 (COVID-19) infection and death has been investigated in several studies. The reported results were controversial, so the objective of the present study was to assess the relationship between different blood groups and the onset and mortality of COVID-19 infection using a meta-analysis method. We searched relevant databases using appropriate MeSH terms. We screened articles on the bases of titles, abstracts and full text, and articles that met the inclusion criteria were selected. Quality assessment was done with the Newcastle-Ottawa scale checklist. The estimated frequency of COVID-19 infection and death in terms of ABO blood group and the overall estimate of the odds ratio between blood group with COVID-19 infection and death was calculated with 95% confidence interval. The pooled frequency of blood groups A, B, O and AB among COVID-19-infected individuals was estimated as 36.22%, 24.99%, 29.67% and 9.29% respectively. The frequency of blood groups A, B, O and AB among patients who died of COVID-19 infection was estimated as 40%, 23%, 29% and 8% respectively. The odds ratio of COVID-19 infection for blood group A versus the other blood groups was estimated as 1.16 (95% confidence interval (CI), 1.02-1.33). The corresponding figures for blood groups O and AB versus other blood groups were estimated as 0.73 (95% CI, 0.60-0.88) and 1.25 (95% CI, 0.84-1.86) respectively. This meta-analysis showed that individuals with blood group A are at higher risk for COVID-19 infection while those with blood group O are at lower risk. Although the odds ratio of death for AB blood group was nonsignificant, it was considerable.

Time-resolved diffraction with an optimized short pulse laser plasma X-ray source.

We present a setup for time-resolved X-ray diffraction based on a short pulse, laser-driven plasma X-ray source. The employed modular design provides high flexibility to adapt the setup to the specific requirements (e.g., X-ray optics and sample environment) of particular applications. The configuration discussed here has been optimized toward high angular/momentum resolution and uses K α -radiation (4.51 keV) from a Ti wire-target in combination with a toroidally bent crystal for collection, monochromatization, and focusing of the emitted radiation. 2 × 10 5 Ti-K α1 photons per pulse with 10 - 4 relative bandwidth are delivered to the sample at a repetition rate of 10 Hz. This allows for the high dynamic range (104) measurements of transient changes in the rocking curves of materials as for example induced by laser-triggered strain waves.

Acute Hepatic Allograft Rejection in Pediatric Recipients: Effective Factors.

BACKGROUND: Acute cellular rejection (ACR), a reversible process, can affect the graft survival. OBJECTIVE: To evaluate the relation between ACR and clinical factors in recipients of allograft liver transplantation. METHODS: 47 recipients of liver were consecutively enrolled in a retrospective study. Their information were retrieved from their medical records and analyzed. RESULTS: Of the 47 recipients, 38 (81%) experienced acute rejection during 24 months of the transplantation. None of the studied factors for occurring transplant rejection, i.e., blood groups, sex, age, familial history of disease, receiving drugs and blood products, type of donor, Child score, and Child class, was not found to be significant. CONCLUSION: During a limited follow-up period, we did not find any association between ACR and suspected risk factors.

Acute Hepatic Allograft Rejection in Pediatric Recipients: Independent Factors.

BACKGROUND: Acute cellular rejection (ACR) has a reversible effect on graft and its survival. OBJECTIVE: To evaluate the relation between ACR and clinical factors in recipients of liver transplant allografts. METHODS: 47 consecutive liver recipients were retrospectively studied. Their data were extracted from records and analyzed. RESULTS: 38 (81%) of the 47 recipients experienced ACR during a 24-month follow-up. The rate of rejection was associated with none of the studied factors-recipient's blood group, sex, age, familial history of disease, drugs and blood products received, type of donor, and Child score and class. CONCLUSION: During a limited follow-up period, we did not find any association between ACR and suspected risk factors.

Prevalence of Non-alcoholic Fatty Liver Disease and Its Related Factors in Iran.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease in developing and developed countries. Estimating the total prevalence of NAFLD by means of appropriate statistical methods can provide reliable evidence for health policy makers. OBJECTIVE: To determine the prevalence of NAFLD in Iran using a systematic review and meta-analysis. METHODS: We identified relevant studies by searching national and international databases. Standard error of the prevalence reported in each study was calculated assuming a binomial distribution. The heterogeneity between the results of the studies was determined using Cochran's Q and I square indices. We used a random effect model to combine the prevalence rates reported in the studies. RESULTS: We entered 23 eligible studies in this systematic review investigated NAFLD among 25,865 Iranian people. The total prevalence of NAFLD, prevalence of mild, moderate and severe fatty liver disease were estimated at 33.9% (95% CI 26.4%-41.5%), 26.7% (95% CI 21.7%-31.7%), 7.6% (95% CI 5.7%-9.4%), and 0.5% (95% CI 0.1%-0.9%), respectively. The majority of studies reported that NAFLD was more common among men (seven of eight studies), obese person (15 of 15 studies), older people (10 of 10 studies), patients with systolic hypertension (5 of 8 studies), patients with diastolic hypertension (7 of 9 studies), patients with hypertriglyceridemia (14 of 16 studies), patients with high HOMA level (4 of 4 studies), patients with metabolic syndrome (4 of 4 studies), and those with elevated serum ALT (8 of 12 studies). CONCLUSION: Our study showed that the prevalence of NAFLD in Iran was relatively high and male gender, old age, diabetes, metabolic syndrome, systolic/diastolic hypertension, high serum ALT, and hypertriglyceridemia may be determinants of NAFLD.

Predictive factors of death in patients with tuberculosis: a nested case-control study.

Tuberculosis is one of the main causes of death worldwide. This study aimed to determine predictive factors for death in patients with tuberculosis to set priorities for public heath interventions to reduce mortality in these patients. This nested case-control study was carried out in Mazandaran province of Islamic Republic of Iran among tuberculosis patients who were treated during 2002-2009. Each deceased patient was individually matched with a control patient according to sex, age, area of involvement and time of follow-up. Potential risk factors for death were evaluated using multivariate conditional logistic regression models. From 2206 patients 376 cases and 376 matched controls were selected. Only positive serology for HIV (OR = 19.1), history of kidney disease (OR = 6.81) and use of immunosuppressant drugs (OR = 3.96) significantly increased the risk of death in tuberculosis patients. These potentially modifiable risk factors could be taken into account in preventive interventions for tuberculosis patients in our country.

Predictive factors of death in patients with tuberculosis:a nested case-control study

Tuberculosis is one of the main causes of death worldwide. This study aimed to determine predictive factors for death in patients with tuberculosis to set priorities for public heath interventions to reduce mortality in these patients. This nested case–control study was carried out in Mazandaran province of Islamic Republic ofIran among tuberculosis patients who were treated during 2002–2009. Each deceased patient was individually matched with a control patient according to sex, age, area of involvement and time of follow-up. Potential risk factors for death were evaluated using multivariate conditional logistic regression models. From 2206 patients 376 cases and 376 matched controls were selected. Only positive serology for HIV (OR = 19.1), history of kidney disease (OR = 6.81) and use of immunosuppressant drugs (OR = 3.96) significantly increased the risk of death in tuberculosis patients. These potentially modifiable risk factors could be taken into account in preventive interventions for tuberculosis patients in our country.

La tuberculose est l'une des principales causes de décès dans le monde. La présente étude avait pour objectif de déterminer les facteurs prédictifs de décès chez des patients atteints de tuberculose afin de fixer des priorités pour les interventions de santé publique visant à réduire la mortalité chez ces patients. Laprésente étude cas-témoin nichée dans une cohorte a été menée dans la province de Mazandaran (République islamique d’Iran) auprès de patients tuberculeux ayant été traités entre 2002 et 2009. Chaque patient décédé a été individuellement apparié à un patient témoin pour le sexe, l'âge et le site de la lésion ainsi que la période de suivi. Des facteurs de risque potentiels de décès ont été évalués à l'aide de modèles de régression logistique conditionnelle multivariée. Sur un total de 2206 patients, 376 cas et 376 témoins appariés ont été sélectionnés. Seuls une sérologie positive pour le VIH (OR = 19,1), des antécédents d'insuffisance rénale (OR = 6,81) et le recours à des immunosuppresseurs (OR = 3,96) augmentaient ignificativement le risque de décès chez ces patients atteints de tuberculose. Ces facteurs de risque potentiellement modifiables pourraient être pris en compte dans des interventions préventives visant les patients atteints de tuberculose dans notre pays.