Histological study of the sex-change in the skunk clownfish <i>Amphiprion akallopisos</i>

Sex change in the protandrous fish Amphiprion akallopisos Bleeker, 1853 (F.Pomacentridae) has been analysed. Experiments consisted of placing males together after being separated from their mates, and observe changes in gonad histology at different periods, in order to identify signs of the sex change process. The presence of a first invagination on the male gonad wall, and the observation of the first cortical alveoli oocytes as an indication of the beginning of the vitellogenesis process, was the first symptom of the sex change, which has been detected after 18 days in one of the males. Period needed for the sex changing process was size independent. The process by which wall invagination is converted into ovarian lumen in the future mature ovary is also described

Small and large intestine (II): Inflammatory bowel disease, short bowel syndrome, and malignant tumors of the digestive tract

The small intestine is key in the digestion and absorption of macro and micronutrients. The large intestine is essential for the absorption of water, to allow adequate defecation, and to har-bor intestinal microbiota, for which their nutritional role is as important as it is unknown. This article will describe the causes and consequences of malnutrition in patients with inflammatory bowel diseases, the importance of screening and replacement of micronutrient deficits, and the main indi-cations for enteral and parenteral nutrition in these patients. We will also discuss the causes of short bowel syndrome, a complex entity due to anatomical or functional loss of part of the small bowel, which can cause insufficient absorption of liquid, electrolytes, and nutrients and lead to complex management. Finally, we will review the causes, consequences, and management of malnutrition in patients with malignant and benign digestive tumors, including neuroendocrine tumors (present not only in the intestine but also in the pancreas). © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Development of the Fetal Vermis: New Biometry Reference Data and Comparison of 3 Diagnostic Modalities-3D Ultrasound, 2D Ultrasound, and MR Imaging

Normal biometry of the fetal posterior fossa rules out most major anomalies of the cerebellum and vermis. Our aim was to provide new reference data of the fetal vermis in 4 biometric parameters by using 3 imaging modalities, 2D ultrasound, 3D ultrasound, and MR imaging, and to assess the relation among these modalities. A retrospective study was conducted between June 2011 and June 2013. Three different imaging modalities were used to measure vermis biometry: 2D ultrasound, 3D ultrasound, and MR imaging. The vermian parameters evaluated were the maximum superoinferior diameter, maximum anteroposterior diameter, the perimeter, and the surface area. Statistical analysis was performed to calculate centiles for gestational age and to assess the agreement among the 3 imaging modalities. The number of fetuses in the study group was 193, 172, and 151 for 2D ultrasound, 3D ultrasound, and MR imaging, respectively. The mean and median gestational ages were 29.1 weeks, 29.5 weeks (range, 21-35 weeks); 28.2 weeks, 29.05 weeks (range, 21-35 weeks); and 32.1 weeks, 32.6 weeks (range, 27-35 weeks) for 2D ultrasound, 3D ultrasound, and MR imaging, respectively. In all 3 modalities, the biometric measurements of the vermis have shown a linear growth with gestational age. For all 4 biometric parameters, the lowest results were those measured by MR imaging, while the highest results were measured by 3D ultrasound. The inter- and intraobserver agreement was excellent for all measures and all imaging modalities. Limits of agreement were considered acceptable for clinical purposes for all parameters, with excellent or substantial agreement defined by the intraclass correlation coefficient. Imaging technique-specific reference data should be used for the assessment of the fetal vermis in pregnanc

The Sunyaev-Zeldovich effect in superclusters of galaxies using gasdynamical simulations: the case of Corona Borealis

[Abridged] We study the thermal and kinetic Sunyaev-Zel'dovich (SZ) effect associated with superclusters of galaxies using the MareNostrum Universe SPH simulation. We consider superclusters similar to the Corona Borealis Supercluster (CrB-SC). This paper is motivated by the detection at 33GHz of a strong temperature decrement in the CMB towards the core of this supercluster. Multifrequency observations with VSA and MITO suggest the existence of a thermal SZ effect component in the spectrum of this cold spot, which would account for roughly 25% of the total observed decrement. We identify nine regions containing superclusters similar to CrB-SC, obtain the associated SZ maps and calculate the probability of finding such SZ signals arising from hot gas within the supercluster. Our results show that WHIM produces a thermal SZ effect much smaller than the observed value. Neither can summing the contribution of small clusters and galaxy groups in the region explain the amplitude of the SZ signal. When we take into account the actual posterior distribution from the observations, the probability that WHIM can cause a thermal SZ signal like the one observed is <1%, rising up to a 3.2% when the contribution of small clusters and galaxy groups is included. If the simulations provide a suitable description of the gas physics, then we conclude that the thermal SZ component of the CrB spot most probably arises from an unknown galaxy cluster along the line of sight. The simulations also show that the kinetic SZ signal associated with the supercluster cannot provide an explanation for the remaining 75% of the observed cold spot in CrB.Comment: Accepted for publication in MNRAS. 14 pages, 9 figure

Loop Model with Generalized Fugacity in Three Dimensions

A statistical model of loops on the three-dimensional lattice is proposed and is investigated. It is O(n)-type but has loop fugacity that depends on global three-dimensional shapes of loops in a particular fashion. It is shown that, despite this non-locality and the dimensionality, a layer-to-layer transfer matrix can be constructed as a product of local vertex weights for infinitely many points in the parameter space. Using this transfer matrix, the site entropy is estimated numerically in the fully packed limit.Comment: 16pages, 4 eps figures, (v2) typos and Table 3 corrected. Refs added, (v3) an error in an explanation of fig.2 corrected. Refs added. (v4) Changes in the presentatio

Process Tomography for Systems in a Thermal State

We propose a new method for implementing process tomography that is based on the information extracted from temporal correlations between observables, rather than on state preparation and state tomography. As such, the approach is applicable to systems that are in a mixed state, and in particular to thermal states. We illustrate the method for an arbitrary evolution described by Kraus operators, as well as for simpler cases such as a general Gaussian channels, and qubit dynamics

How selective are real wage cuts? : a micro-analysis using linked employer-employee data

Using linked employer–employee panel data for Germany, this paper investigates whether firms implement real wage reductions in a selective manner. In line with insider–outsider and several strands of efficiency wage theory, we find strong evidence for selective wage cuts with high-productivity workers being spared even when controlling for permanent differences in firms’ wage policies. In contrast to some recent contributions stressing fairness considerations, we also find that wage cuts increase wage dispersion among peers rather than narrowing it. Notably, the same selectivity pattern shows up when restricting our analysis to firms covered by collective agreements or having a works council

Tunable few-electron double quantum dots and Klein tunnelling in ultra-clean carbon nanotubes

Quantum dots defined in carbon nanotubes are a platform for both basic scientific studies and research into new device applications. In particular, they have unique properties that make them attractive for studying the coherent properties of single electron spins. To perform such experiments it is necessary to confine a single electron in a quantum dot with highly tunable barriers, but disorder has until now prevented tunable nanotube-based quantum-dot devices from reaching the single-electron regime. Here, we use local gate voltages applied to an ultra-clean suspended nanotube to confine a single electron in both a single quantum dot and, for the first time, in a tunable double quantum dot. This tunability is limited by a novel type of tunnelling that is analogous to that in the Klein paradox of relativistic quantum mechanics.Comment: 21 pages including supplementary informatio

Synthesis of Carboxymethyl Starch for increasing drilling mud quality in drilling oil and gas wells

This paper describes the impact of carboxymethyl starch preparation conditions on physicochemical properties of polysaccharide reagent, widely used as fluid loss reducing agent in drilling mud. Variation of the main parameters of carboxymethylation is researched in the experiment. The following conditions such as temperature and reaction time, amount of water, as well as ratio of NaOH to monochloracetic acid define the characteristics of carboxymethyl starch. The degree of substitution is defined for polysaccharides, as well as the characteristics of samples have been studied by infrared spectroscopy. Rheological characteristics and fluid loss indicator have been investigated to study the impact of the reagents on drilling mud quality