Event Structure at RHIC from p-p to Au-Au

Several correlation analysis techniques are applied to p-p and Au-Au collisions at RHIC. Strong large-momentum-scale correlations are observed which can be related to local charge and momentum conservation during hadronization and to minijet (minimum-bias parton fragment) correlations.Comment: 6 pages, 6 figures, 20th Winter Workshop on Nuclear Dynamics, Trelawny Beach, Jamaica, March 15-20, 200

Cholesteatoma and family history: An international survey

Objective To explore the relative frequency of a family history of cholesteatoma in patients with known cholesteatoma, and whether bilateral disease or earlier diagnosis is more likely in those with a family history. Associations between cleft lip or palate and bilateral disease and age of diagnosis were also explored. Design An online survey of patients with diagnosed cholesteatoma was conducted between October 2017 and April 2019. Participants The sample consisted of patients recruited from two UK clinics and self‐selected respondents recruited internationally via social media. Main outcome measures Side of cholesteatoma, whether respondents had any family history of cholesteatoma, age of diagnosis and personal or family history of cleft lip or palate were recorded. Results Of 857 respondents, 89 (10.4%) reported a positive family history of cholesteatoma. Respondents with a family history of cholesteatoma were more likely to have bilateral cholesteatoma (P = .001, odds ratio (OR) 2.15, 95% confidence interval (CI) 1.35‐3.43), but there was no difference in the age of diagnosis (P = .23). Those with a history of cleft lip or palate were not more likely to have bilateral disease (P = .051, OR 2.71, CI 1.00‐7.38), and there was no difference in age of diagnosis (P = .11). Conclusion The relatively high proportion of respondents that reported a family history of cholesteatoma offers supporting evidence of heritability in cholesteatoma. The use of social media to recruit respondents to this survey means that the results cannot be generalised to other populations with cholesteatoma. Further population‐based research is suggested to determine the heritability of cholesteatoma

Dopamine receptor genetic polymorphisms and body composition in undernourished pastoralists: An exploration of nutrition indices among nomadic and recently settled Ariaal men of northern Kenya

<p>Abstract</p> <p>Background</p> <p>Minor alleles of the human dopamine receptor polymorphisms, DRD2/TaqI A and DRD4/48 bp, are related to decreased functioning and/or numbers of their respective receptors and have been shown to be correlated with body mass, height and food craving. In addition, the 7R minor allele of the DRD4 gene is at a higher frequency in nomadic compared to sedentary populations. Here we examine polymorphisms in the DRD2 and DRD4 genes with respect to body mass index (BMI) and height among men in two populations of Ariaal pastoralists, one recently settled (n = 87) and the other still nomadic (n = 65). The Ariaal live in northern Kenya, are chronically undernourished and are divided socially among age-sets.</p> <p>Results</p> <p>Frequencies of the DRD4/7R and DRD2/A1 alleles were 19.4% and 28.2%, respectively and did not differ between the nomadic and settled populations. BMI was higher in those with one or two DRD4/7R alleles in the nomadic population, but lower among the settled. Post-hoc analysis suggests that the DRD4 differences in BMI were due primarily to differences in fat free body mass. Height was unrelated to either DRD2/TaqI A or DRD4/48 bp genotypes.</p> <p>Conclusion</p> <p>Our results indicate that the DRD4/7R allele may be more advantageous among nomadic than settled Ariaal men. This result suggests that a selective advantage mediated through behaviour may be responsible for the higher frequency of the 7R alleles in nomadic relative to sedentary populations around the world. In contrast to previous work, we did not find an association between DRD2 genotypes and height. Our results support the idea that human phenotypic expression of genotypes should be rigorously evaluated in diverse environments and genetic backgrounds.</p

Picking out polymorphs: H-bond prediction and crystal structure stability

A methodology has been developed to predict the propensity for hydrogen bonds to form in crystal structures, treating each potential H-bond as a binary response variable, and modelling its likelihood using a set of relevant chemical descriptors [1]. Modelling is tailored to a target using chemically similar known structures, from e.g. the Cambridge Structural Database [2], making it accessible to the complete spectrum of organic structures, including solvates, hydrates and cocrystals. Recent work has developed the approach to predicting interand intramolecular H-bonds when either type can occur. By way of a comparison between possible and observed H-bonds, the method has been applied to assess structural stability, which shows much promise in the domain of polymorph screening in the pharmaceutical industry. We will introduce the methodology and illustrate its application using a selection of pharmaceutical compounds, one of which will be Abbott’s wellpublicised anti-HIV medication ritonavir (Norvir™). Owing to a hidden, more stable form II with much lower bioavailability, ritonavir was temporarily withdrawn from the market with significant financial impact [3]. Our method quickly suggests a real threat of polymorphism in this compound, and strongly supports the relative stability of form II over form I. For all examples, the high predictivity of the method is emphasised

Modeling of Ni Diffusion Induced Austenite Formation in Ferritic Stainless Steel Interconnects

Ferritic stainless steel interconnect plates are widely used in planar solid oxide fuel cell (SOFC) or electrolysis cell (SOEC) stacks. During stack production and operation, nickel from the Ni/YSZ fuel electrode or from the Ni contact component diffuses into the IC plate, causing transformation of the ferritic phase into an austenitic phase in the interface region. This is accompanied with changes in volume and in mechanical and corrosion properties of the IC plates. In this work, kinetic modeling of the inter-diffusion between Ni and FeCr based ferritic stainless steel was conducted, using the CALPHAD approach with the DICTRA software. The kinetics of inter-diffusion and austenite formation was explored in full detail, as functions of layer thickness, temperature, time, and steel composition. The simulation was further validated by comparing with experimental results. Growth of the austenite phase in commercial interconnect materials is predicted to take place under practical stack operation conditions.</jats:p

Latent Positional Information is in the Self-Attention Variance of Transformer Language Models Without Positional Embeddings

The use of positional embeddings in transformer language models is widely accepted. However, recent research has called into question the necessity of such embeddings. We further extend this inquiry by demonstrating that a randomly initialized and frozen transformer language model, devoid of positional embeddings, inherently encodes strong positional information through the shrinkage of self-attention variance. To quantify this variance, we derive the underlying distribution of each step within a transformer layer. Through empirical validation using a fully pretrained model, we show that the variance shrinkage effect still persists after extensive gradient updates. Our findings serve to justify the decision to discard positional embeddings and thus facilitate more efficient pretraining of transformer language models.Comment: Accepted by ACL 202

Liposomal Co-Entrapment of CD40mAb Induces Enhanced IgG Responses against Bacterial Polysaccharide and Protein

Background Antibody against CD40 is effective in enhancing immune responses to vaccines when chemically conjugated to the vaccine antigen. Unfortunately the requirement for chemical conjugation presents some difficulties in vaccine production and quality control which are compounded when multivalent vaccines are required. We explore here an alternative to chemical conjugation, involving the co-encapsulation of CD40 antibody and antigens in liposomal vehicles. Methodology/Principal Findings Anti-mouse CD40 mAb or isotype control mAb were co-entrapped individually in cationic liposomal vehicles with pneumococcal polysaccharides or diphtheria and tetanus toxoids. Retention of CD40 binding activity upon liposomal entrapment was assessed by ELISA and flow cytometry. After subcutaneous immunization of BALB/c female mice, anti-polysaccharide and DT/TT responses were measured by ELISA. Simple co-encapsulation of CD40 antibody allowed for the retention of CD40 binding on the liposome surface, and also produced vaccines with enhanced imunogenicity. Antibody responses against both co-entrapped protein in the form of tetanus toxoid, and Streptococcus pneumoniae capsular polysaccharide, were enhanced by co-encapsulation with CD40 antibody. Surprisingly, liposomal encapsulation also appeared to decrease the toxicity of high doses of CD40 antibody as assessed by the degree of splenomegaly induced. Conclusions/Significance Liposomal co-encapsulation with CD40 antibody may represent a practical means of producing more immunogenic multivalent vaccines and inducing IgG responses against polysaccharides without the need for conjugation