The use of immunocytochemical markers for the diagnosis of malignancy in serious effusions

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Weighted exponential approximation and non-classical orthogonal spectral measures

A long-standing open problem in harmonic analysis is: given a non-negative measure $\mu$ on $\mathbb R$, find the infimal width of frequencies needed to approximate any function in $L^2(\mu)$. We consider this problem in the "perturbative regime", and characterize asymptotic smallness of perturbations of measures which do not change that infimal width. Then we apply this result to show that there are no local restrictions on the structure of orthogonal spectral measures of one-dimensional Schrodinger operators on a finite interval. This answers a question raised by V.A.Marchenko.Comment: footnote 4 is corrected; some changes are made in the proof of Theorem 2.1

Improved carrier selectivity of diffused silicon wafer solar cells

The majority of commercial solar cells are fabricated on crystalline silicon wafers with diffused homojunctions. This is forecast to continue into the near future. This thesis explores how improving the carrier selectivity of homojunction solar cells can achieve higher conversion efficiencies, by reducing the losses at the contacted and non-contacted surfaces. The carrier conductivity at the metal-silicon contact was investigated for both heavily doped n+ and p+ silicon. For diffused n+ electron collectors, it was shown that thin layers (<5 nm) of aluminium oxide (AlOx) deposited between the silicon nitride (SiNx) and screen-printed silver paste can improve contact resistivity, whereas thicker layers increased the contact resistivity. Through simulation and cell fabrication, this effect was shown to be beneficial for solar cells limited by contact resistance, whereas the adverse effects of thicker layers were mitigated by changing the paste formulation. For diffused p+ hole collectors, a method of electroless plating nickel seed layers to boron diffused silicon was developed which demonstrated contact resistivity’s < 1 mΩ.cm2 for lightly diffused p+ silicon. However, it was found that the contact recombination and contact resistivity was higher for the electroless nickel plated contacts in comparison to aluminium evaporated references. Regarding the non metallised, heavily doped silicon surfaces, improved understanding of the recombination rate at diffused inverted surfaces was achieved through modelling of the injection level dependent lifetime behaviour with technology computer-aided-design (TCAD) simulations. This resulted in the development of a novel contactless method of extracting the interface charge (Q) and surface recombination velocity parameters from passivated and diffused silicon surfaces. This addresses a current limitation of existing interface characterisation techniques, and allows the study of the electronic properties of these highly relevant surfaces. This method was demonstrated on a range of dielectric passivated n+ and p+ surfaces, and the extracted Q values were comparable to results obtained using conventional techniques. Finally, the findings were implemented in TCAD simulations of state-of-the-art homojunction interdigitated back contact (IBC) solar cells, demonstrating the technology potential. This work highlights novel technologies and methods to improve the next generation of diffused silicon wafer solar cells

Searching for the Genus Epidemicus in Chinese Patients: Findings from the Clificol COVID-19 Clinical Case Registry.

BACKGROUND  The Clificol COVID-19 Support Project is an innovative international data collection project aimed at tackling some of the core questions in homeopathy. This paper reports on the further investigation of the genus epidemicus concept during the first wave of the pandemic in the Chinese population. METHODS  The design is an observational clinical case registry study of Chinese patients with confirmed or suspected coronavirus disease 2019 (COVID-19). The symptoms were prospectively collected via a 150-item questionnaire. The concept of genus epidemicus, including the role of treatment individualization, was investigated by analyzing whether presenting symptoms clustered into distinct groups. Two standard statistical analysis techniques were utilized: principal component analysis for extracting the most meaningful symptoms of the dataset; the k-means clustering algorithm for automatically assigning groups based on similarity between presenting symptoms. RESULTS  20 Chinese practitioners collected 359 cases in the first half of 2020 (766 consultations, 363 prescriptions). The cluster analysis found two to be the optimum number of clusters. These two symptomatic clusters had a high overlap with the two most commonly prescribed remedies in these sub-populations: in cluster 1 there were 297 prescriptions, 95.6% of which were Gelsemium sempervirens; in cluster 2 there were 61 prescriptions, 95.1% of which were Bryonia alba. CONCLUSION  This is the first study to investigate the notion of genus epidemicus by using modern statistical techniques. These analyses identified at least two distinct symptom pictures. The notion of a single COVID-19 genus epidemicus did not apply in the studied population

Inkjet Patterned Anodic Aluminum Oxide for Rear Metal Contacts of Silicon Solar Cells

AbstractLocal rear metal contacting through passivating dielectric layers has the ability to increase silicon solar cell efficiencies to over 20%. To-date most contact schemes have involved the formation of localised aluminium-alloyed regions through patterned AlOx or SiNx passivating layers. Recently electrochemically-formed anodic aluminium oxide (AAO) layers have been shown to enhance minority carrier lifetimes of phosphorus–diffused p-type CZ wafers when formed over an intervening layer of SiO2 or SiNx, suggesting that these layers may find applications as passivation layers for cells. We report here on the inkjet patterning of AAO layers formed over a thermally-grown thin oxide layer on p-type silicon surfaces. The process, which involves the inkjet printing of 50% (w/w) phosphoric acid, was used to form well-resolved arrays of holes with a diameter as small as 20-40μm in the dielectric stack. Alloying of aluminium, which was evaporated over the patterned dielectric stack, resulted in the formation of localised back surface field (BSF) regions having a thickness up to 8μm. Future work will focus on adapting this process for use in local rear metal contacting of silicon solar cells

Antenatal Steroid Therapy for Fetal Lung Maturation and the Subsequent Risk of Childhood Asthma: A Longitudinal Analysis

This study was designed to test the hypothesis that fetal exposure to corticosteroids in the antenatal period is an independent risk factor for the development of asthma in early childhood with little or no effect in later childhood. A population-based cohort study of all pregnant women who resided in Nova Scotia, Canada, and gave birth to a singleton fetus between 1989 and 1998 was undertaken. After a priori specified exclusions, 80,448 infants were available for analysis. Using linked health care utilization records, incident asthma cases developed after 36 months of age were identified. Extended Cox proportional hazards models were used to estimate hazard ratios while controlling for confounders. Exposure to corticosteroids during pregnancy was associated with a risk of asthma in childhood between 3–5 years of age: adjusted hazard ratio of 1.19 (95% confidence interval: 1.03, 1.39), with no association noted after 5 years of age: adjusted hazard ratio for 5–7 years was 1.06 (95% confidence interval: 0.86, 1.30) and for 8 or greater years was 0.74 (95% confidence interval: 0.54, 1.03). Antenatal steroid therapy appears to be an independent risk factor for the development of asthma between 3 and 5 years of age

UNIT project: Universe NN-body simulations for the Investigation of Theoretical models from galaxy surveys

We present the UNIT $N$-body cosmological simulations project, designed to provide precise predictions for nonlinear statistics of the galaxy distribution. We focus on characterizing statistics relevant to emission line and luminous red galaxies in the current and upcoming generation of galaxy surveys. We use a suite of precise particle mesh simulations (FastPM) as well as with full $N$-body calculations with a mass resolution of $\sim 1.2\times10^9\,h^{-1}$M$_{\odot}$ to investigate the recently suggested technique of Angulo & Pontzen 2016 to suppress the variance of cosmological simulations We study redshift space distortions, cosmic voids, higher order statistics from $z=2$ down to $z=0$. We find that both two- and three-point statistics are unbiased. Over the scales of interest for baryon acoustic oscillations and redshift-space distortions, we find that the variance is greatly reduced in the two-point statistics and in the cross correlation between halos and cosmic voids, but is not reduced significantly for the three-point statistics. We demonstrate that the accuracy of the two-point correlation function for a galaxy survey with effective volume of 20 ($h^{-1}$Gpc)$^3$ is improved by about a factor of 40, indicating that two pairs of simulations with a volume of 1 ($h^{-1}$Gpc)$^3$ lead to the equivalent variance of $\sim$150 such simulations. The $N$-body simulations presented here thus provide an effective survey volume of about seven times the effective survey volume of DESI or Euclid. The data from this project, including dark matter fields, halo catalogues, and their clustering statistics, are publicly available at http://www.unitsims.org.Comment: 12 pages, 9 figures. This version matches the one accepted by MNRAS. The data from this project are publicly available at: http://www.unitsims.or

The Merging of a Coronal Dimming and the Southern Polar Coronal Hole

We report on the merging between the southern polar coronal hole and an adjacent coronal dimming induced by a coronal mass ejection on 2022 March 18, resulting in the merged region persisting for at least 72 hr. We use remote sensing data from multiple co-observing spacecraft to understand the physical processes during this merging event. The evolution of the merger is examined using Extreme-UltraViolet (EUV) images obtained from the Atmospheric Imaging Assembly on board the Solar Dynamic Observatory and Extreme Ultraviolet Imager, which is on board the Solar Orbiter spacecraft. The plasma dynamics are quantified using spectroscopic data obtained from the EUV Imaging Spectrometer on board Hinode. The photospheric magnetograms from the Helioseismic and Magnetic Imager are used to derive the magnetic field properties. To our knowledge, this work is the first spectroscopical analysis of the merging of two open-field structures. We find that the coronal hole and the coronal dimming become indistinguishable after the merging. The upflow speeds inside the coronal dimming become more similar to that of a coronal hole, with a mixture of plasma upflows and downflows observable after the merging. The brightening of the bright points and the appearance of coronal jets inside the merged region further imply ongoing reconnection processes. We propose that component reconnection between the coronal hole and coronal dimming fields plays an important role during this merging event because the footpoint switching resulting from the reconnection allows the coronal dimming to intrude onto the boundary of the southern polar coronal hole

RORγ is a targetable master regulator of cholesterol biosynthesis in a cancer subtype.

Tumor subtype-specific metabolic reprogrammers could serve as targets of therapeutic intervention. Here we show that triple-negative breast cancer (TNBC) exhibits a hyper-activated cholesterol-biosynthesis program that is strongly linked to nuclear receptor RORγ, compared to estrogen receptor-positive breast cancer. Genetic and pharmacological inhibition of RORγ reduces tumor cholesterol content and synthesis rate while preserving host cholesterol homeostasis. We demonstrate that RORγ functions as an essential activator of the entire cholesterol-biosynthesis program, dominating SREBP2 via its binding to cholesterol-biosynthesis genes and its facilitation of the recruitment of SREBP2. RORγ inhibition disrupts its association with SREBP2 and reduces chromatin acetylation at cholesterol-biosynthesis gene loci. RORγ antagonists cause tumor regression in patient-derived xenografts and immune-intact models. Their combination with cholesterol-lowering statins elicits superior anti-tumor synergy selectively in TNBC. Together, our study uncovers a master regulator of the&nbsp;cholesterol-biosynthesis program and an attractive target for TNBC

Understanding the Relationship between Solar Coronal Abundances and F10.7 cm Radio Emission

Sun-as-a-star coronal plasma composition, derived from full-Sun spectra, and the F10.7 radio flux (2.8 GHz) have been shown to be highly correlated (r = 0.88) during solar cycle 24. However, this correlation becomes nonlinear during increased solar magnetic activity. Here we use cotemporal, high spatial resolution, multiwavelength images of the Sun to investigate the underlying causes of the nonlinearity between coronal composition (FIP bias) and F10.7 solar index correlation. Using the Karl G. Jansky Very Large Array, Hinode/EIS (EUV Imaging Spectrometer), and the Solar Dynamics Observatory, we observed a small active region, AR 12759, throughout the solar atmosphere from the photosphere to the corona. The results of this study show that the magnetic field strength (flux density) in active regions plays an important role in the variability of coronal abundances, and it is likely the main contributing factor to this nonlinearity during increased solar activity. Coronal abundances above cool sunspots are lower than in dispersed magnetic plage regions. Strong magnetic concentrations are associated with stronger F10.7 cm gyroresonance emission. Considering that as the solar cycle moves from minimum to maximum, the sizes of sunspots and their field strength increase with the gyroresonance component, the distinctly different tendencies of radio emission and coronal abundances in the vicinity of sunspots is the likely cause of saturation of Sun-as-a-star coronal abundances during solar maximum, while the F10.7 index remains well correlated with the sunspot number and other magnetic field proxies