Smooth Particle Hydrodynamics-Based Characteristics of a Shaped Jet from Different Materials

The liner material is one of the key factors in the design of armor-piercing ammunition that effect the penetration efficiency. The performance of a shaped jet formed by the charge liner is determined by different properties of the material under the blasting action, in particular for the target with explosive reactive armor, which diminishes the penetration power by dispersing the shaped jet. The performance of shaped jet elements from different materials is studied, AUTODYN finite element software and smooth particle hydrodynamics method are employed to simulate the formation of shaped jet elements from the three materials: Cu, PTFE, and PTFE/Cu and their penetration into target plates, which was verified in the experiment. A shaped jet for a Cu liner is shown to be formed under the action of a detonation wave, while PTFE and PTFE/Cu materials generate a dispersive particle jet. The head velocity of a Cu jet is found to be the lowest, the penetration depth is the deepest, and the penetration hole size is the smallest; the velocity of a PTFE particle jet is the highest and the penetration depth is the shallowest, the penetration hole size takes the mid-position; the head velocity and penetration depth of a PTFE/Cu jet take the mid-position, while the penetration hole is the largest. The PTFE/Cu jet possesses higher penetration performance as compared to the PTFE jet, and its hole-opening capability is improved as compared to the Cu jet.Облицовочный материал один из ключевых факторов при создании бронебойных боеприпасов, оказывающий влияние на эффективность внедрения. Работоспособность кумулятивного заряда, формируемого его облицовкой, определяется различными свойствами материала в условиях взрывной нагрузки, в частности для мишени с элементами динамической защиты, которые уменьшают проникающую способность, рассеивая кумулятивный заряд. Изучены рабочие характеристики элементов кумулятивного заряда из различных материалов. Конечноэлементное программное обеспечение AUTODYN и метод гидродинамики гладких частиц используются при моделировании формирования этих элементов и их внедрении в пластинымишени из трех материалов: Cu, ПТФЭ и ПТФЭ/Сu, что было проверено экспериментально. Показано, что кумулятивный заряд для медной облицовки формируется под действием детонационной волны, тогда как ПТФЭ и ПТФЭ/Cu материалы генерируют струю распыленных частиц. Установлено, что в головной части скорость струи частиц Сu наименьшая, глубина внедрения наибольшая, а размер отверстий наименьший, скорость струи частиц ПТФЭ наибольшая, глубина внедрения наименьшая, размер отверстий занимает среднее положение, скорость и глубина внедрения струи частиц ПТФЭ/Сu занимают среднее положение, тогда как отверстия имеют наибольший размер. Струя частиц ПТФЭ/Сu обладает более высокой эффективностью внедрения по сравнению со струей ПТФЭ, а ее проникающая способность выше, чем струи Cu.Облицювальний матеріал - один з ключових чинників при створенні бронебійних боєприпасів, який впливає на ефективність заглиблення. Працездатність кумулятивного заряду, який формується його облицюванням, визначається різними властивостями матеріалу в умовах вибухового навантаження, зокрема для мішені з елементами динамічного захисту, які зменшують проникаючу здатність, розсіюючи кумулятивний заряд. Вивчено робочі характеристики елементів кумулятивного заряду з різних матеріалів. Скінчнноелементне програмне забезпечення AUTODYN і метод гідродинаміки гладких частинок використовуються при моделюванні формування цих елементів і їх впровадженні в пластини-мішені з трьох матеріалів: Cu, ПТФЕ і ПТФЕ / Cu, що було перевірено експериментально. Показано, що кумулятивний заряд для мідного облицювання формується під дією детонаційної хвилі, тоді як ПТФЕ і ПТФЕ / Cu матеріали генерують струмінь розпорошених частинок. Встановлено, що в головній частині швидкість струменя частинок Cu найменша, глибина заглиблення найбільша, а розмір отворів менший, швидкість струменя частинок ПТФЕ найбільша, глибина заглиблення найменша, розмір отворів займає середнє положення, швидкість і глибина заглиблення струменя частинок ПТФЕ / Cu займають середнє положення, тоді як отвори мають найбільший розмір. Струмінь частинок ПТФЕ / Cu володіє більш високою ефективністю заглиблення в порівнянні зі струменем ПТФЕ, а її проникаюча здатність вище, ніж струменя Cu

Kondo lattice model with a direct exchange interaction between localized moments

We study the Kondo lattice model with a direct antiferromagnetic exchange interaction between localized moments. Ferromagnetically long-range ordered state coexisting with the Kondo screening shows a continuous quantum phase transition to the Kondo singlet state. We obtain the value of the critical point where the magnetizations of the localized moments and the conduction electrons vanish. The magnetization curves yield a universal critical exponent independent of the filling factors and the strength of the interaction between localized moments. It is shown that the direct exchange interaction between localized moments introduces another phase transition from an antiferromagnetic ordering to a ferromagnetic ordering for small Kondo exchange interaction. We also explain the local minimum of the Kondo temperature in recent experiments.Comment: 6 pages, 5 figures, final versio

Phase diagram for morphological transitions of wetting films on chemically structured substrates

Using an interface displacement model we calculate the shapes of thin liquidlike films adsorbed on flat substrates containing a chemical stripe. We determine the entire phase diagram of morphological phase transitions in these films as function of temperature, undersaturation, and stripe widthComment: 15 pages, RevTeX, 7 Figure

Platelet-activating factor (PAF) mediates NLRP3-NEK7 inflammasome induction independently of PAFR

The role of lipids in inflammasome activation remains underappreciated. The phospholipid, platelet-activating factor (PAF), exerts multiple physiological functions by binding to a G protein-coupled seven-transmembrane receptor (PAFR). PAF is associated with a number of inflammatory disorders, yet the molecular mechanism underlying its proinflammatory function remains to be fully elucidated. We show that multiple PAF isoforms and PAF-like lipids can activate the inflammasome, resulting in IL-1β and IL-18 maturation. This is dependent on NLRP3, ASC, caspase-1, and NEK7, but not on NLRC4, NLRP1, NLRP6, AIM2, caspase-11, or GSDMD. Inflammasome activation by PAF also requires potassium efflux and calcium influx but not lysosomal cathepsin or mitochondrial reactive oxygen species. PAF exacerbates peritonitis partly through inflammasome activation, but PAFR is dispensable for PAF-induced inflammasome activation in vivo or in vitro. These findings reveal that PAF represents a damage-associated signal that activates the canonical inflammasome independently of PAFR and provides an explanation for the ineffectiveness of PAFR antagonist in blocking PAF-mediated inflammation in the clinic

Nitric oxide and cyclic nucleotides: Their roles in junction dynamics and spermatogenesis

Spermatogenesis is a highly complicated process in which functional spermatozoa (haploid, 1n) are generated from primitive mitotic spermatogonia (diploid, 2n). This process involves the differentiation and transformation of several types of germ cells as spermatocytes and spermatids undergo meiosis and differentiation. Due to its sophistication and complexity, testis possesses intrinsic mechanisms to modulate and regulate different stages of germ cell development under the intimate and indirect cooperation with Sertoli and Leydig cells, respectively. Furthermore, developing germ cells must translocate from the basal to the apical (adluminal) compartment of the seminiferous epithelium. Thus, extensive junction restructuring must occur to assist germ cell movement. Within the seminiferous tubules, three principal types of junctions are found namely anchoring junctions, tight junctions, and gap junctions. Other less studied junctions are desmosome-like junctions and hemidesmosome junctions. With these varieties of junction types, testes are using different regulators to monitor junction turnover. Among the uncountable junction modulators, nitric oxide (NO) is a prominent candidate due to its versatility and extensive downstream network. NO is synthesized by nitric oxide synthase (NOS). Three traditional NOS, specified as endothelial NOS (eNOS), inducible NOS (iNOS), and neuronal NOS (nNOS), and one testis-specific nNOS (TnNOS) are found in the testis. For these, eNOS and iNOS were recently shown to have putative junction regulation properties. More important, these two NOSs likely rely on the downstream soluble guanylyl cyclase/cGMP/protein kinase G signaling pathway to regulate the structural components at the tight junctions and adherens junctions in the testes. Apart from the involvement in junction regulation, NOS/NO also participates in controlling the levels of cytokines and hormones in the testes. On the other hand, NO is playing a unique role in modulating germ cell viability and development, and indirectly acting on some aspects of male infertility and testicular pathological conditions. Thus, NOS/NO bears an irreplaceable role in maintaining the homeostasis of the microenvironment in the seminiferous epithelium via its different downstream signaling pathways

Application of a risk-management framework for integration of stromal tumor-infiltrating lymphocytes in clinical trials

Stromal tumor-infiltrating lymphocytes (sTILs) are a potential predictive biomarker for immunotherapy response in metastatic triple-negative breast cancer (TNBC). To incorporate sTILs into clinical trials and diagnostics, reliable assessment is essential. In this review, we propose a new concept, namely the implementation of a risk-management framework that enables the use of sTILs as a stratification factor in clinical trials. We present the design of a biomarker risk-mitigation workflow that can be applied to any biomarker incorporation in clinical trials. We demonstrate the implementation of this concept using sTILs as an integral biomarker in a single-center phase II immunotherapy trial for metastatic TNBC (TONIC trial, NCT02499367), using this workflow to mitigate risks of suboptimal inclusion of sTILs in this specific trial. In this review, we demonstrate that a web-based scoring platform can mitigate potential risk factors when including sTILs in clinical trials, and we argue that this framework can be applied for any future biomarker-driven clinical trial setting

Measurement of the View the tt production cross-section using eμ events with b-tagged jets in pp collisions at √s = 13 TeV with the ATLAS detector

This paper describes a measurement of the inclusive top quark pair production cross-section (σtt¯) with a data sample of 3.2 fb−1 of proton–proton collisions at a centre-of-mass energy of √s = 13 TeV, collected in 2015 by the ATLAS detector at the LHC. This measurement uses events with an opposite-charge electron–muon pair in the final state. Jets containing b-quarks are tagged using an algorithm based on track impact parameters and reconstructed secondary vertices. The numbers of events with exactly one and exactly two b-tagged jets are counted and used to determine simultaneously σtt¯ and the efficiency to reconstruct and b-tag a jet from a top quark decay, thereby minimising the associated systematic uncertainties. The cross-section is measured to be: σtt¯ = 818 ± 8 (stat) ± 27 (syst) ± 19 (lumi) ± 12 (beam) pb, where the four uncertainties arise from data statistics, experimental and theoretical systematic effects, the integrated luminosity and the LHC beam energy, giving a total relative uncertainty of 4.4%. The result is consistent with theoretical QCD calculations at next-to-next-to-leading order. A fiducial measurement corresponding to the experimental acceptance of the leptons is also presented

Search for TeV-scale gravity signatures in high-mass final states with leptons and jets with the ATLAS detector at sqrt [ s ] = 13TeV

A search for physics beyond the Standard Model, in final states with at least one high transverse momentum charged lepton (electron or muon) and two additional high transverse momentum leptons or jets, is performed using 3.2 fb−1 of proton–proton collision data recorded by the ATLAS detector at the Large Hadron Collider in 2015 at √s = 13 TeV. The upper end of the distribution of the scalar sum of the transverse momenta of leptons and jets is sensitive to the production of high-mass objects. No excess of events beyond Standard Model predictions is observed. Exclusion limits are set for models of microscopic black holes with two to six extra dimensions