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A comparison of computers codes used to solve the semi-classical Boltzmann equation that represents electron transport in silicon helps generate a transport simulation scheme that provides approximate solutions to the Boltzmann transport equation. The Monte Carlo particle technique, the basis of most of the codes, helps evaluate transport characteristics such as impact ionization and average electron energy. Variations are seen in input parameters and physical models developed to simulate estimated transport characteristics.

Impurity scattering limited mobility is examined in a quantum wire. Carriers and cylindrical symmetry of the wire are assumed, and a comparison of the computed mobility with that of approximations of the Dirac wave-function reveals that the wave function shape determines mobility. Similar outputs are observed in both models at increased temperatures. A large spacer employed in quantum wires enhances the properties demonstrated by electron-transport.

III-V heterostructure characteristics of parallel high-field transport are modeled using a Monte Carlo model which assumes the satellite valley quantization, impact of nonparabolicity, secondary well existence within the barriers and electron states of a two-dimensional nature. Heterostructure electron transport is affected by band structure. Schrodinger and Poisson equations lead to the computation of eigenenergies and wave functions. Saturation of velocity, negative differential mobility and peak velocity are also assessed in double heterojunction structures.

Impurity scattering limited mobility in quantum wells was investigated using wave-function modeling. The results showed that Dirac and sine wave functions for an infinite square quantum well produced the same evolutions of the mobility with temperature, carrier density and well width. The presence of electrons inside the doped barrier exerted a strong influence on the mobility.

Presents a study which presented a model of properties in a ferroelectric lead-zirconium-titanium-oxide thin film and applied it to the study of the influence of space charges on hysteresis properties. Model description; Results and discussion; Conclusion.

A two dimensional lattice model for investigating ferroelectric states in thin film materials is presented. This model makes it possible to take account of surface effects. It was found that, in general, including surface effect in the calculations also needs the taking into account of the field induced by the bound charges.

Gymnastics is a closed-skill sport, and the repeatability of a specific technique is accepted as a valuable indicator of a performer's level of expertise. The circle movement, defined as a gyrating movement in the horizontal plane, is a key component of all contemporary pommel horse exercises. The aims of this study were to determine the spatial consistency of the circle movement and to assess the influence of expertise on the repeatability of this skill performed on the pedagogic pommel horse. Six expert gymnasts and six nonexperts performed 10 circles on this apparatus. A 3-dimensional analysis system recorded the trajectories of 6 markers fixed on the right and left ankles, hips, and shoulders. The spatiotemporal consistency was assessed by the SD of the marker trajectories during the circle sequence. The results showed that the shoulder and trajectories were more consistent than the ankle trajectory (P < 0.05); the marker trajectories were less consistent in the sagittal plane (P < 0.05); and the expert gymnasts showed better repeatability of the ankle trajectory than the nonexpert gymnasts did (P < 0.05). In this context, the use of the SD of the ankle trajectory during the circle sequence could be an interesting tool for trainers to quantify objectively the positional errors of the legs during circular swings and to measure the improvement in movements after specific training. [ABSTRACT FROM AUTHOR]

We have studied the polarization switching in ferroelectric particles by using a time dependent Ginzburg Landau model. The surface effect is described by considering the polarization enhancement towards the surface. The influence of this phenomena and related bound charges field on switching properties is extensively discussed and their implication on the local switching mechanism has been elucidated. In particular, we have demonstrated that the effect of the bound charges field strongly depends on the location inside the particle and on the moment of the switching process. [ABSTRACT FROM AUTHOR]

Aims and Objectives: Initiation of palliative care early in the disease trajectory is beneficial for patients with a life-limiting disease. However, palliative care is still introduced rather late or not at all. Therefore, this study aims to explore barriers and facilitators to early initiation of palliative care as perceived by nurses working on pneumology and nephrology., Methods: A descriptive interview-based study was conducted from a critical realist perspective until data sufficiency was reached. Fifteen nurses presented and discussed a patient for whom palliative care was initiated too late. Template analysis was conducted to develop themes and subthemes., Results: Five key themes were extracted: (1) communication, (2) fear, (3) personal beliefs about life and death, (4) ambiguity in terminology and (5) workload and time pressure. Barriers related to poor interdisciplinary communication were therapeutic obstinance, hierarchy, unawareness of the patient's wishes and fear of saying something inappropriate. Other barriers were patients' religious beliefs which often hindered the use of sedatives or morphine and led to discomfort and time restraints. A palliative support team in hospital and advance care planning (ACP) were enablers for early palliative care., Study Limitations: This study started from a negative experience, leading to identification of a lot of barriers and only a few facilitators. The limited sample size and the restriction to two wards within one single hospital limit the diversity of perspectives and the generalisability of the findings., Conclusion: More attention is needed for ACP and interdisciplinary communication. Palliative care, including ACP, and interdisciplinary communication should be included in the basic curricula of all healthcare professional courses. Further research is needed to explore barriers and facilitators to early initiation of palliative care in other healthcare settings and patient populations. This is crucial in order to develop and implement sustainable interventions for specific groups of patients., (© 2024 Nordic College of Caring Science.)

The evolutionary origins of Bilateria remain enigmatic. One of the more enduring proposals highlights similarities between a cnidarian-like planula larva and simple acoel-like flatworms. This idea is based in part on the view of the Xenacoelomorpha as an outgroup to all other bilaterians which are themselves designated the Nephrozoa (protostomes and deuterostomes). Genome data can provide important comparative data and help understand the evolution and biology of enigmatic species better. Here, we assemble and analyze the genome of the simple, marine xenacoelomorph Xenoturbella bocki , a key species for our understanding of early bilaterian evolution. Our highly contiguous genome assembly of X. bocki has a size of ~111 Mbp in 18 chromosome-like scaffolds, with repeat content and intron, exon, and intergenic space comparable to other bilaterian invertebrates. We find X. bocki to have a similar number of genes to other bilaterians and to have retained ancestral metazoan synteny. Key bilaterian signaling pathways are also largely complete and most bilaterian miRNAs are present. Overall, we conclude that X. bocki has a complex genome typical of bilaterians, which does not reflect the apparent simplicity of its body plan that has been so important to proposals that the Xenacoelomorpha are the simple sister group of the rest of the Bilateria., Competing Interests: PS, PN, DL, HR, FL, FM, BF, LB, FS, EH, AZ, PK, KH, SM, MM, HM, RC, RK, PS, MT No competing interests declared, (© 2024, Schiffer et al.)

Genome-wide chromatin conformation capture assays provide formidable insights into the spatial organization of genomes. However, due to the complexity of the data structure, their integration in multi-omics workflows remains challenging. We present data structures, computational methods and visualization tools available in Bioconductor to investigate Hi-C, micro-C and other 3C-related data, in R. An online book ( https://bioconductor.org/books/OHCA/ ) further provides prospective end users with a number of workflows to process, import, analyze and visualize any type of chromosome conformation capture data., (© 2024. The Author(s).)

The European flat oyster ( Ostrea edulis L.) is a native bivalve of the European coasts. Harvest of this species has declined during the last decades because of the appearance of two parasites that have led to the collapse of the stocks and the loss of the natural oyster beds. O. edulis has been the subject of numerous studies in population genetics and on the detection of the parasites Bonamia ostreae and Marteilia refringens. These studies investigated immune responses to these parasites at the molecular and cellular levels. Several genetic improvement programs have been initiated especially for parasite resistance. Within the framework of a European project (PERLE 2) that aims to produce genetic lines of O. edulis with hardiness traits (growth, survival, resistance) for the purpose of repopulating natural oyster beds in Brittany and reviving the culture of this species in the foreshore, obtaining a reference genome becomes essential as done recently in many bivalve species of aquaculture interest. Here, we present a chromosome-level genome assembly and annotation for the European flat oyster, generated by combining PacBio, Illumina, 10X linked, and Hi-C sequencing. The finished assembly is 887.2 Mb with a scaffold-N50 of 97.1 Mb scaffolded on the expected 10 pseudochromosomes. Annotation of the genome revealed the presence of 35,962 protein-coding genes. We analyzed in detail the transposable element (TE) diversity in the flat oyster genome, highlighted some specificities in tRNA and miRNA composition, and provided the first insight into the molecular response of O. edulis to M. refringens . This genome provides a reference for genomic studies on O. edulis to better understand its basic physiology and as a useful resource for genetic breeding in support of aquaculture and natural reef restoration., Competing Interests: The authors declare no conflicts of interest., (© 2022 The Authors. Evolutionary Applications published by John Wiley & Sons Ltd.)

Over the last decade, genomic proximity ligation approaches have reshaped our vision of chromosomes 3D organizations, from bacteria nucleoids to larger eukaryotic genomes. The different protocols (3Cseq, Hi-C, TCC, MicroC [XL], Hi-CO, etc.) rely on common steps (chemical fixation digestion, ligation…) to detect pairs of genomic positions in close proximity. The most common way to represent these data is a matrix, or contact map, which allows visualizing the different chromatin structures (compartments, loops, etc.) that can be associated to other signals such as transcription, protein occupancy, etc. as well as, in some instances, to biological functions.In this chapter we present and discuss the filtering of the events recovered in proximity ligation experiments as well as the application of the balancing normalization procedure on the resulting contact map. We also describe a computational tool for visualizing normalized contact data dubbed Scalogram.The different processes described here are illustrated and supported by the laboratory custom-made scripts pooled into "hicstuff," an open-access python package accessible on github ( https://github.com/koszullab/hicstuff )., (© 2022. Springer Science+Business Media, LLC, part of Springer Nature.)

Bdelloid rotifers are notorious as a speciose ancient clade comprising only asexual lineages. Thanks to their ability to repair highly fragmented DNA, most bdelloid species also withstand complete desiccation and ionizing radiation. Producing a well-assembled reference genome is a critical step to developing an understanding of the effects of long-term asexuality and DNA breakage on genome evolution. To this end, we present the first high-quality chromosome-level genome assemblies for the bdelloid Adineta vaga , composed of six pairs of homologous (diploid) chromosomes with a footprint of paleotetraploidy. The observed large-scale losses of heterozygosity are signatures of recombination between homologous chromosomes, either during mitotic DNA double-strand break repair or when resolving programmed DNA breaks during a modified meiosis. Dynamic subtelomeric regions harbor more structural diversity (e.g., chromosome rearrangements, transposable elements, and haplotypic divergence). Our results trigger the reappraisal of potential meiotic processes in bdelloid rotifers and help unravel the factors underlying their long-term asexual evolutionary success.