Atomistic study of an ideal metal/thermoelectric contact: the full-Heusler/half-Heusler interface

Half-Heusler alloys such as the (Zr,Hf)NiSn intermetallic compounds are important thermoelectric materials for converting waste heat into electricity. Reduced electrical resistivity at the hot interface between the half-Heusler material and a metal contact is critical for device performance, however this has yet to be achieved in practice. Recent experimental work suggests that a coherent interface between half-Heusler and full-Heusler compounds can form due to diffusion of transition metal atoms into the vacant sublattice of the half-Heusler lattice. We study theoretically the structural and electronic properties of such an interface using a first-principles based approach that combines {\it ab initio} calculations with macroscopic modeling. We find that the prototypical interface HfNi$_2$Sn/HfNiSn provides very low contact resistivity and almost ohmic behavior over a wide range of temperatures and doping levels. Given the potential of these interfaces to remain stable over a wide range of temperatures, our study suggests that full-Heuslers might provide nearly ideal electrical contacts to half-Heuslers that can be harnessed for efficient thermoelectric generator devices.Comment: 8 pages, 8 figure

Changes in clinical and CT manifestations related to liver abscesses in patients with vs. without basic diabetes mellitus before and after CT-guided interventional therapy: An observational study

Purpose: To explore differences in the changes of clinical and CT manifestations related to liver abscess before and after CT-guided interventional therapy between patients with and without Diabetes Mellitus (DM). Materials and methods: Fifty-eight consecutive patients with liver abscesses were retrospectively enrolled in this study. All patients underwent upper abdominal contrast-enhanced CT scans before and after CT-guided interventional therapy. They were divided into two groups including the DM group (n=30) and the Non-DM group (n=28) if the liver abscess occurred in patients with and without DM, respectively. The changes in the clinical and CT manifestations related to liver abscess after CT-guided interventional therapy in both groups were statistically analyzed. Results: After CT-guided interventional therapy, the length of hospital stay, white blood cell recovery time and drainage tube removal time in the DM group were longer than in the Non-DM group (all p-values < 0.05). The incidence of postoperative complications in the DM group was higher than in the Non-DM group (p < 0.05). As shown on CT, the postoperative reduced percentage of maximum diameter of abscess cavity and the reduction rate of edema band surrounding the liver abscess in the DM group were smaller than in the Non-DM group (both p-values < 0.05). The time intervals of the previous characteristic changes on CT before and after interventional therapy in the DM group were longer than in the Non-DM group (all p-values < 0.05). Conclusions: The liver abscesses patients with DM could not have a faster recovery and better therapeutic effect than those without DM after the CT-guided interventional therapy

A novel compound heterozygous variant of ECEL1 induced joint dysfunction and cartilage degradation: a case report and literature review

BackgroundDistal arthrogryposis type 5D (DA5D) represents a subtype of distal arthrogryposis (DA) characterized by congenital joint contractures in the distal extremities. DA5D is inherited in a rare autosomal recessive manner and is associated with the ECEL1 gene. In this report, we describe a case of an infant with bilateral knee contractures and ptosis, caused by a novel compound heterozygous mutation of ECEL1.Case presentationWe conducted DNA extraction, whole-exome sequencing analysis, and mutation analysis of ECEL1 to obtain genetic data on the patient. We subsequently analyzed the patient’s clinical and genetic data. The proband was a 6 months-old male infant who presented with significant bilateral knee contracture disorders and bilateral ptosis. MRI demonstrated cartilage degradation in knee joint. Whole-exome sequencing of the patient’s DNA revealed a compound heterozygous mutation of c.2152-15C>A and c.110_155del in ECEL1. Analysis with the MutationTaster application indicated that c.110_155del was pathogenic (probability = 1), causing frameshift mutations affecting 151 amino acids (p.F37Cfs*151). The truncated protein lost the substructure of a transmembranous site based on the predicted protein crystal structure AF-O95672-F1. The variant of c.2152-15C>A of ECEL1 was also predicted to be disease-causing (probability = 0.98) as it impaired the methylation of ECEL1 serving as an H3K27me3 modification site, which led to the dysfunction of the second topological domain. Therefore, we concluded that the compound heterozygous mutation caused the pathogenic phenotype of this proband.ConclusionThe present case highlights the usefulness of molecular genetic screening in diagnosing unexpected joint disorder. Identification of novel mutations in the ECEL1 gene broadens the mutation spectrum of this gene and adds to the genotype-phenotype map of DA5D. Furthermore, rapid whole-exome sequencing analysis enabled timely diagnosis of this rare disease, facilitating appropriate treatment and scheduled follow-up to improve clinical outcomes

Hydrogenation of Mg film and Mg nanoblade array on Ti coated Si substrates

The hydrogenation of Mg film and Mg nanoblade array fabricated on Ti coated Si substrates has been studied and compared. The nanoblades start to absorb hydrogen at a temperature between 250 and 300 degrees C, which is much lower than 350 degrees C for Mg film. However, the saturated total hydrogen uptake in nanoblades is less than half of that in the film, resulting from MgO formation by air exposure. The nanoblade morphology with large surface area and small hydrogen diffusion length, and the catalytic effect of Ti layer, are two main reasons for the nanoblade hydrogenation behavior

Design Of Electronic Stability Control (ESC) Systems For Car-Trailer Combinations

This paper presents the design of an electronic stability control (ESC) system based on trailer differential braking for increasing safety and improving handling performance of car-trailer combinations. Numerical simulations were performed using CarSim software to assess the performance of the proposed control strategies of the ESC system. To validate the virtual design of the ESC system for car-trailer combinations, a small scaled physical prototype (1:10) of a car-trailer combination was fabricated and tested. The prototype consists of an aluminum frame, accelerometer, and two wheels equipped with an electromagnetic differential braking. Numerical simulation and prototype testing demonstrated the effectiveness of the proposed ESC system for car-trailer combinations