An optical model analysis of the available data for A = 8 (
8
He,
8
Li and
8
B) projectiles on different targets with light, medium and heavy mass has been performed. A systematic potential set based ...on a Woods–Saxon Potential shape was obtained. This potential describes the elastic scattering angular distributions quite well. A more physical model within the framework of a semi-microscopic approach, where the nuclear matter density distributions of the
8
B,
8
Li and
8
He projectiles have been calculated by using a microscopic self-consistent relativistic mean field (RMF) theory, was also considered. The agreement of the calculated angular distributions with the data was reasonable. An improvement of the agreement could be achieved by changing the imaginary diffuseness parameter, which is a sensitive parameter in these calculations.
We present a review of the formalism and give some of the applications of polarization potentials in heavy ion scattering, placing special attention on the contributions of Prof. Mahir Hussein to the ...field. In particular, we discuss Feshbach’s formalism and show its applications to the case of coupling to rotational and vibrational states, in both the quantum mechanical and semiclassical cases.
We establish a relationship between the nucleon-nucleon interaction potential and the nuclear fusion reaction cross-sections at low energies. The axially deformed self-consistent relativistic mean ...field is used with the non-linear NL3* interaction parameter set. The Wong formula is used to estimate the fusion cross-section for 58Ni + 58Ni and 48Ca + 238U systems, which are known to display fusion hindrance phenomena. The results of the application of the nucleus-nucleus optical potential for the fusion cross-section from the recently developed effective relativistic NN-interaction (R3Y) potential is compared with the well-known, phenomenological M3Y potential. The results obtained from our present calculation for the R3Y interaction are reasonable good as compared to the M3Y potential concerning the available experimental at barrier energies. The present analysis pursues a full microscopic studies of fusion process at low energies by taking the R3Y potential along with the relativistic mean field density instead of taking the M3Y interaction within the double folding approach.
As genome sequencing becomes better integrated into scientific research, government policy, and personalized medicine, the primary challenge for researchers is shifting from generating raw data to ...analyzing these vast datasets. Although much work has been done to reduce compute times using various configurations of traditional CPU computing infrastructures, Graphics Processing Units (GPUs) offer opportunities to accelerate genomic workflows by orders of magnitude. Here we benchmark one GPU-accelerated software suite called NVIDIA Parabricks on Amazon Web Services (AWS), Google Cloud Platform (GCP), and an NVIDIA DGX cluster. We benchmarked six variant calling pipelines, including two germline callers (HaplotypeCaller and DeepVariant) and four somatic callers (Mutect2, Muse, LoFreq, SomaticSniper).
We achieved up to 65 × acceleration with germline variant callers, bringing HaplotypeCaller runtimes down from 36 h to 33 min on AWS, 35 min on GCP, and 24 min on the NVIDIA DGX. Somatic callers exhibited more variation between the number of GPUs and computing platforms. On cloud platforms, GPU-accelerated germline callers resulted in cost savings compared with CPU runs, whereas some somatic callers were more expensive than CPU runs because their GPU acceleration was not sufficient to overcome the increased GPU cost.
Germline variant callers scaled well with the number of GPUs across platforms, whereas somatic variant callers exhibited more variation in the number of GPUs with the fastest runtimes, suggesting that, at least with the version of Parabricks used here, these workflows are less GPU optimized and require benchmarking on the platform of choice before being deployed at production scales. Our study demonstrates that GPUs can be used to greatly accelerate genomic workflows, thus bringing closer to grasp urgent societal advances in the areas of biosurveillance and personalized medicine.
High rates of mental health symptoms such as depression, anxiety, and posttraumatic stress disorder (PTSD) have been found in patients hospitalized with traumatic injuries, but little is known about ...these problems in patients hospitalized with acute illnesses. A similarly high prevalence of mental health problems in patients hospitalized with acute illness would have significant public health implications because acute illness and injury are both common, and mental health problems of depression, anxiety, and PTSD are highly debilitating.
In patients admitted after emergency care for Acute Illness (N = 656) or Injury (N = 661) to three hospitals across the United States, symptoms of depression, anxiety, and posttraumatic stress were compared acutely (Acute Stress Disorder) and two months post-admission (PTSD). Patients were ethnically/racially diverse and 54% female. No differences were found between the Acute Illness and Injury groups in levels of any symptoms acutely or two months post-admission. At two months post-admission, at least one symptom type was elevated for 37% of the Acute Illness group and 39% of the Injury group. Within racial/ethnic groups, PTSD symptoms were higher in Black patients with injuries than for Black patients with acute illness. A disproportionate number of Black patients had been assaulted.
This study found comparable levels of mental health sequelae in patients hospitalized after emergency care for acute illness as in patients hospitalized after emergency care for injury. Findings of significantly higher symptoms and interpersonal violence injuries in Black patients with injury suggest that there may be important and actionable differences in mental health sequelae across ethnic/racial identities and/or mechanisms of injury or illness. Routine screening for mental health risk for all patients admitted after emergency care could foster preventive care and reduce ethnic/racial disparities in mental health responses to acute illness or injury.
Friction stir processing (FSP) improves the mechanical properties of metals by refining grains to submicron scale. It also introduces significant basal texture in ultrafine grained magnesium alloy by ...tilting the basal poles by various degrees with respect to the depth in the nugget. This texture results in much higher tensile stress and ductility, but lower uniform strain in the transverse direction, than in the processing direction. This paper discusses the effect of FSP-induced texture on anisotropy in mechanical behavior.
Nucleon-induced pre-equilibrium reactions are important in many applications of nuclear physics. About 20% of the particles emitted in such reactions are composites, such as deuterons and alpha ...particles. Deuterons are produced through emission from the compound nucleus, as well as through two important direct reaction mechanisms - "pick-up" and coalescence. Iwamoto and Harada developed a semi-classical pre-equilibrium model that describes both direct mechanisms as a generalization of coalescence. We have implemented the Iwamato and Harada unified model of deuteron emission in Blann and Chadwick's hybrid Monte Carlo model. This implementation was made in order to analyse data of reactions of the type (p,d), that is, proton induced reactions having deuterons as emitted particles, but our previous results were not satisfactory. In order to find a new approach for the deuteron emission, we are investigating an eikonal approximation to the phase space of Iwamoto and Harada model. We are also comparing our angular distributions with the experimental ones using DWUCK4. Nevertheless, our results are not satisfactory yet and our work is under development.
We present calculations of deuteron elastic and nonelastic breakup cross sections and angular distributions at deuteron energies below 100 MeV obtained using the post-form DWBA approximation. The ...elastic breakup cross section was extensively studied in the past. Very few calculations of nonelastic breakup have been performed, however. We compare two forms of the elastic DWBA breakup amplitude but conclude that neither provides a correct description of the inclusive proton emission cross section.
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