67 research outputs found

    Determination of nutrient values of the bivalve Anodonta cygnea in Selkeh area of the Anzali Lagoon during autumn and spring

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    Anzali Lagoon is one of the most important aquatic ecosystems of Iran which was registered as a Ramsar Convention site in 1999. This valuable ecosystem is located in the south west shores of the Caspian Sea, in Guilan Province. We randomly collected 30 and 20 samples of the bivalve Anodonta cygnea in autumn 2004 and spring 2005 respectively. The Selkeh area was chosen for the sampling because of its availability during autumn. The area receives water from the southern part of the lagoon basin. Nutrient content of the soft tissue of the bivalve was measured. Live sampled bivalves were transferred to laboratory and their length, width, height; total body weight and wet weight of the internal soft part were measured. Moisture, ash, protein, T.V.N, lipid and amino acid contents in soft tissue were also determined. Moisture content in spring and autumn samples were 84.84% and 83.6%, respectively. Ash content in autumn samples was higher than spring samples, being 4% and 2.32%, respectively. Assessment showed protein content in the autumn samples to be 12% while in spring samples this was 10.5%. T.V.N content in autumn and spring samples were 0.031 and 0.003% respectively. Measurements showed that autumn bivalves had 4% lipid content whereas this value in spring samples was 3%. We found Sixtheen amino acids, including seven essential ones in the samples

    Comparison of qualitative characteristics of fish paste produced from minced kilka (Clupeonella cultriventris) and silver carp (Hypophthalmichthys molitrix)

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    The aim of this study was to determine the qualitative characteristics of ready-made fish paste made from minced meat (Clupeonella cultriventris) and silver carp (Hypophthalmichthys molitrix) and its shelf-life at a refrigerated temperature.This compilation was performed in five treatments including amounts 100, 75, 50 and 25 percent of processed fish meat were cured. The treatments were packed in heat-resistant glass after pasteurization. Samples were stored at 4oC for 40 days.The amount of TVB-N in the experimental treatments during the course of the change was increased that this factor varied between15.25-31.25 mg/100 g of meat in experimental treatments. This factor was in the 100% rolled silver carp treatment until the end of the shelf life in the standard range. The amount of tybarbibacteric acid increased during storage period varied between 0.13- 2.11mg malondialdehyde/1000g in experimental treatments, but this factor was in the 100% treatment of silver carp paste after the end of the maintenance period in the standard range (less than 1.8 mg/100gr), in other treatments, after 30 days, was more than standard limitation. The pH changes in treatments did not significantly decrease (P>0.05), this factor varied between 5.05 to 5.93 in the experimental period. Total bacterial counts, psychrophilic bacteria and coliform and molds were not observed in experimental treatments during storage period. Microbial contamination was not observed during the storage period in the refrigerator in the experimental treatments. The taste and texture in silver carp treatment (100%) were better than other treatments. The ash, protein and fat in 5 treatments did not significantly change during storage (p>0.05). The moisture content was not significantly increased in all five treatments during storage (p>0.05). Results showed treatment of processed carp (100%) was better than other treatments (p<0.05)

    Toward Evidence-Based Antiracist Policymaking: Problems and Proposals for Better Racial Data Collection and Reporting

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    The study of data concerning racial and ethnic inequities and disparities allows us to better understand experiences of racism, and to see more clearly how and where racism manifests. Studying the effects of racism, in turn, allows us to more easily identify racist policies, so that we can craft antiracist interventions. Existing race and ethnicity data collection efforts are riddled with gaps and errors, including missing and incomplete data, insufficiently disaggregated data, lack of meaningful longitudinal data, infrequently updated data, non-standardized methodologies, and other problems. These deficiencies significantly hinder evidence-based antiracist policymaking. This policy report examines the state of racial and ethnic demographic data collection and reporting in the U.S., and offers policy recommendations to improve such systems. In particular, this report demonstrates the need for a standardized and nation-wide system of racial data collection and reporting. This report is based on the experiences of two teams of researchers that collected racial and ethnic data between March 2020 and August 2021: The COVID Racial Data Tracker (CRDT) and the Racial Data Tracker (RDT). The CRDT, a collaboration between The Atlantic’s COVID Tracking Project and the BU Center for Antiracist Research (the Center), was the first public database containing racial demographic data about COVID-19 cases, hospitalizations, and deaths across the U.S. The RDT, a Center initiative, collects racial and ethnic data in several other policy areas, including houselessness, criminal arrests, and police violence. The CRDT and RDT teams’ experiences, described in this Report, demonstrate the current challenges of obtaining racial and ethnic data across different jurisdictions, levels of government, and policy areas, and offer critical insight as to how to reform racial and ethnic data collection and reporting practices in the U.S

    Inverse Hall Petch Like Mechanical Behaviour in Nanophase Al-Cu-Fe Quasicrystals: A New Phenomenon

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    The structural and mechanical stability of quasicrystals are important issues due to their potential for possible applications at high temperatures and stresses. The aim of the present work is, therefore, to review the earlier works on conventional crystalline and quasicrystalline materials and also to report the results and the analysis on the Hall Petch and inverse Hall Petch like behavior of nanoquasicrystalline Al62.5Cu25Fe12.5 alloys. It was observed that, at large grain sizes, the hardness increases with decreasing grain size, exhibiting the conventional Hall Petch relationship, whereas for smaller grains, inverse Hall Petch behavior was identified. The inverse Hall Fetch behavior in the nanoquasicrystalline phase could be attributed to thermally activated shearing of the grain boundaries, leading to grain boundary sliding in nanostructures of quasicrystalline grains. These results were analyzed based on the dislocation pile-up model as well as the grain boundary shearing models applicable to nanomaterials

    Contribution of Somatic Ras/Raf/Mitogen-Activated Protein Kinase Variants in the Hippocampus in Drug-Resistant Mesial Temporal Lobe Epilepsy

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    Importance: Mesial temporal lobe epilepsy (MTLE) is the most common focal epilepsy subtype and is often refractory to antiseizure medications. While most patients with MTLE do not have pathogenic germline genetic variants, the contribution of postzygotic (ie, somatic) variants in the brain is unknown. Objective: To test the association between pathogenic somatic variants in the hippocampus and MTLE. Design, Setting, and Participants: This case-control genetic association study analyzed the DNA derived from hippocampal tissue of neurosurgically treated patients with MTLE and age-matched and sex-matched neurotypical controls. Participants treated at level 4 epilepsy centers were enrolled from 1988 through 2019, and clinical data were collected retrospectively. Whole-exome and gene-panel sequencing (each genomic region sequenced more than 500 times on average) were used to identify candidate pathogenic somatic variants. A subset of novel variants was functionally evaluated using cellular and molecular assays. Patients with nonlesional and lesional (mesial temporal sclerosis, focal cortical dysplasia, and low-grade epilepsy-associated tumors) drug-resistant MTLE who underwent anterior medial temporal lobectomy were eligible. All patients with available frozen tissue and appropriate consents were included. Control brain tissue was obtained from neurotypical donors at brain banks. Data were analyzed from June 2020 to August 2022. Exposures: Drug-resistant MTLE. Main Outcomes and Measures: Presence and abundance of pathogenic somatic variants in the hippocampus vs the unaffected temporal neocortex. Results: Of 105 included patients with MTLE, 53 (50.5%) were female, and the median (IQR) age was 32 (26-44) years; of 30 neurotypical controls, 11 (36.7%) were female, and the median (IQR) age was 37 (18-53) years. Eleven pathogenic somatic variants enriched in the hippocampus relative to the unaffected temporal neocortex (median [IQR] variant allele frequency, 1.92 [1.5-2.7] vs 0.3 [0-0.9]; P =.01) were detected in patients with MTLE but not in controls. Ten of these variants were in PTPN11, SOS1, KRAS, BRAF, and NF1, all predicted to constitutively activate Ras/Raf/mitogen-activated protein kinase (MAPK) signaling. Immunohistochemical studies of variant-positive hippocampal tissue demonstrated increased Erk1/2 phosphorylation, indicative of Ras/Raf/MAPK activation, predominantly in glial cells. Molecular assays showed abnormal liquid-liquid phase separation for the PTPN11 variants as a possible dominant gain-of-function mechanism. Conclusions and Relevance: Hippocampal somatic variants, particularly those activating Ras/Raf/MAPK signaling, may contribute to the pathogenesis of sporadic, drug-resistant MTLE. These findings may provide a novel genetic mechanism and highlight new therapeutic targets for this common indication for epilepsy surgery

    Schizophrenia-associated somatic copy-number variants from 12,834 cases reveal recurrent NRXN1 and ABCB11 disruptions

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    While germline copy-number variants (CNVs) contribute to schizophrenia (SCZ) risk, the contribution of somatic CNVs (sCNVs)—present in some but not all cells—remains unknown. We identified sCNVs using blood-derived genotype arrays from 12,834 SCZ cases and 11,648 controls, filtering sCNVs at loci recurrently mutated in clonal blood disorders. Likely early-developmental sCNVs were more common in cases (0.91%) than controls (0.51%, p = 2.68e−4), with recurrent somatic deletions of exons 1–5 of the NRXN1 gene in five SCZ cases. Hi-C maps revealed ectopic, allele-specific loops forming between a potential cryptic promoter and non-coding cis-regulatory elements upon 5′ deletions in NRXN1. We also observed recurrent intragenic deletions of ABCB11, encoding a transporter implicated in anti-psychotic response, in five treatment-resistant SCZ cases and showed that ABCB11 is specifically enriched in neurons forming mesocortical and mesolimbic dopaminergic projections. Our results indicate potential roles of sCNVs in SCZ risk

    Crystallization of polymorphs:the effect of solvent

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    The effect of solvent in crystallization of polymorphs has been studied using the drug sulphathiazole as a model compound. The solubilities of the four polymorphic forms of sulphathiazole were determined as a function of temperature in various solvents. Within the temperature ranges studied, the rank order of solubility of the polymorphs was the same in all solvent systems. On the basis of this knowledge of the temperature dependence of the solubilities, recrystallization experiments, in which the supersaturation was systematically varied, were carried out in an endeavour to isolate each of the polymorphic forms from each solvent system. These recrystallization experiments reveal that not all of the known polymorphic forms can be crystallized from any given solvent by varying the supersaturation. Indeed some solvents selectively favour the crystallization of a particular form or forms. We conclude that thermodynamic effects are not responsible for the selective behaviour of a solvent. A kinetic mechanism is proposed. It is considered that the solvent acts by selective adsorption to certain faces of some of the polymorphs, and thereby either inhibits their nucleation or retards their growth to the advantage of others

    Computer simulation of crystal-liquid interface:application to wettability of solids

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    Purpose. This study describes the development and application of a molecular simulation technique for investigating the solid-liquid interface. It attempts to relate the molecular and crystal structure to the observed wettability of solids. Method Molecular simulations have been carried out for the crystal-water interface of a series of N-n-alkyl-D-gluconamide crystals using the Monte Carlo technique. The molecular system simulated consisted of a layer of water bounded by two crystal slabs. The interfacial potential energies were calculated for the crystal-water interactions and compared with experimental enthalpy values obtained from contact angle measurements. Results. The simulations clearly reveal the distinct hydrophilic and hydrophobic nature of the respective (010) and (0(1) over bar0$) faces of these compounds. The distribution of water at the interface observed in the simulations is in accord with the nature of the crystal faces. The calculated interfacial potential energies are in the right ball park, but consistently higher than the experimental values. The disparity, however, is justifiable, resulting from the highly simplified model simulated. Conclusions. Using the developed molecular simulation technique one can calculate the wettability of a solid given the crystal structure. This approach represents an important step towards the goal of engineering crystals with desired wettability characteristics

    Dynamic, Cell-Type-Specific Roles for GABAergic Interneurons in a Mouse Model of Optogenetically Inducible Seizures

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    GABAergic interneurons play critical roles in seizures, but it remains unknown whether these vary across interneuron subtypes or evolve during a seizure. This uncertainty stems from the unpredictable timing of seizures in most models, which limits&nbsp;neuronal imaging or manipulations around the seizure onset. Here, we describe a mouse model for optogenetic seizure induction. Combining this with calcium imaging, we find that seizure onset rapidly recruits parvalbumin (PV), somatostatin (SOM), and vasoactive intestinal peptitde (VIP)-expressing interneurons, whereas excitatory neurons are recruited several seconds later. Optogenetically inhibiting VIP interneurons consistently increased seizure threshold and reduced seizure duration. Inhibiting PV+ and SOM+ interneurons had mixed effects on seizure initiation but consistently reduced seizure duration. Thus, while their roles may evolve during seizures, PV+ and SOM+ interneurons ultimately help maintain ongoing seizures. These results show how an optogenetically induced seizure model can be leveraged to pinpoint a new target for seizure control: VIP interneurons. VIDEO ABSTRACT
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