Unusual presentation of Kaposi sarcoma in an HIV-negative woman

Kaposi sarcoma typically presents as violaceous macules and papules in immunocompromised, specifically HIV-positive, patients. Its distinct clinical features often facilitate rapid diagnosis. In this article, we report a case of Kaposi sarcoma presenting as a concerning yet nondescript lesion in an HIV-negative woman. Although Kaposi sarcoma is frequently part of the differential diagnosis for skin lesions affecting HIV-positive patients, it is less frequently considered in HIV-negative individuals. Additionally, this case differs from the classic clinical presentation of Kaposi sarcoma by resembling a squamous cell carcinoma or superficial basal cell carcinoma. Therefore, it illustrates the importance of suspicious lesion biopsies to ensure accurate diagnosis and appropriate treatment

Calibration Of The Johnson–Cook Model At High Temperatures For An Ultra-High Strength CrNiMoV Steel

This paper presents a study on the thermo-mechanical behavior of an ultra-high strength CrNiMoV steel at high temperatures and medium strain rates through hot tensile tests. The material was examined in two conditions: as-cast/heat-treated (AC/HT) and as-rolled (AR). Tensile tests were conducted at temperatures of 800,900,1000,1100, and 1200°C, and strain rates of 0.1,1, and 10s−1. Inclusion and porosity analysis was also performed on the tensile specimens. The results revealed that the flow stress decreased by approximately 70% on average from 800°C to 1200°C, while increasing by approximately 32% on average from 0.1s−1 to 10s−1 in strain rate. The elongation exhibited an increase from 16.5% at 800°C to 33% at 1200°C. However, the ductility transition was slower than expected, particularly for the AC/HT conditions. The AC/HT samples exhibited higher levels of inclusions and porosity compared to the AR samples, with porosity significantly affecting the elongation to failure and ultimate tensile strength (UTS) at a strain rate of 1s−1. Furthermore, calibrated Johnson–Cook parameters were reported and compared, demonstrating excellent agreement between predicted and experimental values with less than 20% variation. The calibrated Johnson–Cook model can be effectively employed for modeling purposes within the studied temperature range, and its application can even be extrapolated for higher strain rates

The electric double layer has a life of its own

Using molecular dynamics simulations with recently developed importance sampling methods, we show that the differential capacitance of a model ionic liquid based double-layer capacitor exhibits an anomalous dependence on the applied electrical potential. Such behavior is qualitatively incompatible with standard mean-field theories of the electrical double layer, but is consistent with observations made in experiment. The anomalous response results from structural changes induced in the interfacial region of the ionic liquid as it develops a charge density to screen the charge induced on the electrode surface. These structural changes are strongly influenced by the out-of-plane layering of the electrolyte and are multifaceted, including an abrupt local ordering of the ions adsorbed in the plane of the electrode surface, reorientation of molecular ions, and the spontaneous exchange of ions between different layers of the electrolyte close to the electrode surface. The local ordering exhibits signatures of a first-order phase transition, which would indicate a singular charge-density transition in a macroscopic limit

Key dimensions of women’s and their partners’ experiences of childbirth: A systematic review of reviews of qualitative studies

Background The World Health Organization 2018 intrapartum guideline for a positive birth experience emphasized the importance of maternal emotional and psychological well-being during pregnancy and the need for safe childbirth. Today, in many countries birth is safe, yet many women report negative and traumatic birth experiences, with adverse effects on their and their families’ well-being. Many reviews have attempted to understand the complexity of women’s and their partners’ birth experience; however, it remains unclear what the key dimensions of the birth experience are. Objective To synthesize the information from reviews of qualitative studies on the experience of childbirth in order to identify key dimensions of women’s and their partners’ childbirth experience. Methods Systematic database searches yielded 40 reviews, focusing either on general samples or on specific modes of birth or populations, altogether covering primary studies from over 35,000 women (and >1000 partners) in 81 countries. We appraised the reviews’ quality, extracted data and analysed it using thematic analysis. Findings Four key dimensions of women’s and partners’ birth experience (covering ten subthemes), were identified: 1) Perceptions, including attitudes and beliefs; 2) Physical aspects, including birth environment and pain; 3) Emotional challenges; and 4) Relationships, with birth companions and interactions with healthcare professionals. In contrast with the comprehensive picture that arises from our synthesis, most reviews attended to only one or two of these dimensions. Conclusions The identified key dimensions bring to light the complexity and multidimensionality of the birth experience. Within each dimension, pathways leading towards negative and traumatic birth experiences as well as pathways leading to positive experiences become tangible. Identifying key dimensions of the birth experience may help inform education and research in the field of birth experiences and gives guidance to practitioners and policy makers on how to promote positive birth experiences for women and their partners

To respond or not to respond - a personal perspective of intestinal tolerance

For many years, the intestine was one of the poor relations of the immunology world, being a realm inhabited mostly by specialists and those interested in unusual phenomena. However, this has changed dramatically in recent years with the realization of how important the microbiota is in shaping immune function throughout the body, and almost every major immunology institution now includes the intestine as an area of interest. One of the most important aspects of the intestinal immune system is how it discriminates carefully between harmless and harmful antigens, in particular, its ability to generate active tolerance to materials such as commensal bacteria and food proteins. This phenomenon has been recognized for more than 100 years, and it is essential for preventing inflammatory disease in the intestine, but its basis remains enigmatic. Here, I discuss the progress that has been made in understanding oral tolerance during my 40 years in the field and highlight the topics that will be the focus of future research

Entropy-driven liquid-liquid separation in supercooled water

Twenty years ago Poole et al. (Nature 360, 324, 1992) suggested that the anomalous properties of supercooled water may be caused by a critical point that terminates a line of liquid-liquid separation of lower-density and higher-density water. Here we present an explicit thermodynamic model based on this hypothesis, which describes all available experimental data for supercooled water with better quality and with fewer adjustable parameters than any other model suggested so far. Liquid water at low temperatures is viewed as an 'athermal solution' of two molecular structures with different entropies and densities. Alternatively to popular models for water, in which the liquid-liquid separation is driven by energy, the phase separation in the athermal two-state water is driven by entropy upon increasing the pressure, while the critical temperature is defined by the 'reaction' equilibrium constant. In particular, the model predicts the location of density maxima at the locus of a near-constant fraction (about 0.12) of the lower-density structure.Comment: 7 pages, 6 figures. Version 2 contains an additional supplement with tables for the mean-field equatio

A Twisted Kink Crystal in the Chiral Gross-Neveu model

We present the detailed properties of a self-consistent crystalline chiral condensate in the massless chiral Gross-Neveu model. We show that a suitable ansatz for the Gorkov resolvent reduces the functional gap equation, for the inhomogeneous condensate, to a nonlinear Schr\"odinger equation, which is exactly soluble. The general crystalline solution includes as special cases all previously known real and complex condensate solutions to the gap equation. Furthermore, the associated Bogoliubov-de Gennes equation is also soluble with this inhomogeneous chiral condensate, and the exact spectral properties are derived. We find an all-orders expansion of the Ginzburg-Landau effective Lagrangian and show how the gap equation is solved order-by-order.Comment: 28 pages, 13 figs; v2: new appendix on Eilenberger eq and refs; version in PR

Watson–Crick and Sugar-Edge Base Pairing of Cytosine in the Gas Phase: UV and Infrared Spectra of Cytosine·2-Pyridone

While keto-amino cytosine is the dominant species in aqueous solution, spectroscopic studies in molecular beams and in noble gas matrices show that other cytosine tautomers prevail in apolar environments. Each of these offers two or three H-bonding sites (Watson–Crick, wobble, sugar-edge). The mass- and isomer-specific S1 ← S0 vibronic spectra of cytosine·2-pyridone (Cyt·2PY) and 1-methylcytosine·2PY are measured using UV laser resonant two-photon ionization (R2PI), UV/UV depletion, and IR depletion spectroscopy. The UV spectra of the Watson–Crick and sugar-edge isomers of Cyt·2PY are separated using UV/UV spectral hole-burning. Five different isomers of Cyt·2PY are observed in a supersonic beam. We show that the Watson–Crick and sugar-edge dimers of keto-amino cytosine with 2PY are the most abundant in the beam, although keto-amino-cytosine is only the third most abundant tautomer in the gas phase. We identify the different isomers by combining three different diagnostic tools: (1) methylation of the cytosine N1–H group prevents formation of both the sugar-edge and wobble isomers and gives the Watson–Crick isomer exclusively. (2) The calculated ground state binding and dissociation energies, relative gas-phase abundances, excitation and the ionization energies are in agreement with the assignment of the dominant Cyt·2PY isomers to the Watson–Crick and sugar-edge complexes of keto-amino cytosine. (3) The comparison of calculated ground state vibrational frequencies to the experimental IR spectra in the carbonyl stretch and NH/OH/CH stretch ranges strengthen this identification

Запозичення як фактор розвитку базових концептів англійської мови (на прикладі концепту dwelling)

Розвиток лексичної та концептуальної систем англійської мови в значній мірі визначається роллю запозиченого матеріалу. Особливий інтерес становить трансформація цих систем в давньоанглійський період, який характеризується використанням запозичених одиниць на мовному рівні та зіткненням двох етносів, отже, двох концептуальних світів – на культурологічному і когнітивному. Об’єктом дослідження статті є базовий концепт антропології повсякденності dwelling, що відображує як загально-специфічні, так і культурно-специфічні особливості етносу, що запозичує.Развитие лексической и концептуальной систем английского языка во многом определяется ролью заимствованного материала. Особый интерес представляет собой трансформация данных систем в древнеанглийский период, характеризующийся использованием заимствованных единиц на языковом уровне и столкновением двух этносов, следовательно, двух концептуальных миров – на культурологическом и когнитивном. Объектом исследования в данной статье является базовый концепт антропологии повседневности dwelling, отражающий как обще-специфичные, так и культурноспецифичные особенности заимствующего этноса.The development of the English language lexical and conceptual systems is determined by the role of the borrowed material. The particular interest lies in the transformation of these systems in the old English period that is characterized by the usage of the borrowed units on the lexical level and by the interaction of two ethnoses, i.e. two conceptual worlds – on the cultural and cognitive levels. The object of the investigation in the given article is represented by the basic concept of everyday anthropology ‘dwelling’, reflecting both generally specific and culturally specific peculiarities of the borrowing ethnos

Management of colorectal cancer presenting with synchronous liver metastases

Up to a fifth of patients with colorectal cancer (CRC) present with synchronous hepatic metastases. In patients with CRC who present without intestinal obstruction or perforation and in whom comprehensive whole-body imaging confirms the absence of extrahepatic disease, evidence indicates a state of equipoise between several different management pathways, none of which has demonstrated superiority. Neoadjuvant systemic chemotherapy is advocated by current guidelines, but must be integrated with surgical management in order to remove the primary tumour and liver metastatic burden. Surgery for CRC with synchronous liver metastases can take a number of forms: the 'classic' approach, involving initial colorectal resection, interval chemotherapy and liver resection as the final step; simultaneous removal of the liver and bowel tumours with neoadjuvant or adjuvant chemotherapy; or a 'liver-first' approach (before or after systemic chemotherapy) with removal of the colorectal tumour as the final procedure. In patients with rectal primary tumours, the liver-first approach can potentially avoid rectal surgery in patients with a complete response to chemoradiotherapy. We overview the importance of precise nomenclature, the influence of clinical presentation on treatment options, and the need for accurate, up-to-date surgical terminology, staging tests and contemporary management options in CRC and synchronous hepatic metastatic disease, with an emphasis on multidisciplinary care