Miracle-dz/UniFAR-FTUs huggingface dataset:
Exploration of the role of reactive oxygen species in glutamate neurotoxicity in rat hippocampal neurones in culture

1 Exposure of hippocampal neurones to glutamate at toxic levels is associated with a profound collapse of mitochondrial potential and deregulation of calcium homeostasis. We have explored the contributions of reactive oxygen species (ROS) to these events, considered to represent the first steps in the progression to cell death. 2 Digital imaging techniques were used to monitor changes in cytosolic Ca2+ concentration ([Ca2+]c; fura‐2FF) and mitochondrial potential (Δψm; rhodamine 123); rates of ROS generation were assessed using hydroethidium (HEt); and membrane currents were measured with the whole‐cell configuration of the patch clamp technique. 3 Inhibitors of lipid peroxidation (trolox plus ascorbate) and scavengers of superoxide or hydrogen peroxide (manganese(III) tetrakis(4‐benzoic acid) porphyrin (MnTBAP) and TEMPO plus catalase), had only minimal impact on the mitochondrial depolarisation and the sustained increase in [Ca2+]c during and following a 10 min exposure to glutamate. 4 The antioxidants completely suppressed ROS generated by xanthine with xanthine oxidase. No significant increase in ROS production was detected with HEt during a 10 min glutamate exposure. 5 A combination of antioxidants (TEMPO, catalase, trolox and ascorbate) delayed but did not prevent the glutamate‐induced mitochondrial depolarisation and the secondary [Ca2+]c rise. However, this was attributable to a transient inhibition of the NMDA current by the antioxidants. 6 Despite their inability to attenuate the glutamate‐induced collapse of Δψm and destabilisation of [Ca2+]c homeostasis, the antioxidants conferred significant protection in assays of cell viability at 24 h after a 10 min excitotoxic challenge. The data obtained suggest that antioxidants exert their protective effect against glutamate‐induced neuronal death through steps downstream of a sustained increase in [Ca2+]c associated with the collapse of Δψm.
The relation between user intervention and user satisfaction for information recommendation

Although recommender systems have come to give recommendations with high precision, users are not always satisfied with the recommendations. User satisfaction is apparently influenced by many other factors. We specifically examined user intervention as one factor influencing user satisfaction. We tested two hypotheses: user intervention itself improves user satisfaction; and the more users intervene in the recommendation process, the more they are satisfied with the recommendations. We conducted an experiment incorporating user intervention of several kinds to reveal the relation between user intervention and user satisfaction.
The Suprachiasmatic Nucleus: A 25-Year Retrospective

The suprachiasmatic nuclei (SCN) of the anterior hypothalamus contain the master circadian pacemaker in mammals. On the occasion of the 25th anniversary of the discovery of the SCN as the circadian clock, Charles A. Czeisler and Steven M. Reppert organized a meeting to review milestones and recent developments in the study of the SCN. The discovery that the SCN contain tissue necessary for generation of circadian rhythmicity was established by lesion studies published in 1972. The second phase of study demonstrated unequivocally that the SCN contain an autonomous circadian pacemaker. The principal studies in this period showed the presence of metabolic and electrical activity rhythms in the SCN in vivo and progressed to studies showing that the SCN maintain rhythmicity in vitro, demonstrating that the transplanted SCN can restore circadian function following destruction of the host SCN and ultimately showing that single SCN “clock cells” exhibit independent rhythms in firing rate. The third phase of study, aimed at identifying the biochemical and molecular mechanisms responsible for rhythmicity within the SCN, has begun with the identification of circadian mutants (tau mutant hamsters and Clock mutant mice) and the isolation of the Clock gene. This report traces the important steps forward in our understanding of the suprachiasmatic circadian clock by recounting the information presented at the SCN Silver Anniversary Celebration.
Improved Opportunistic Sleeping Algorithms for LAN Switches

Network interfaces in most LAN computing devices are usually severely under-utilized, wasting energy while waiting for new packets to arrive. In this paper, we present two algorithms for opportunistically powering down unused network interfaces in order to save some of that wasted energy. We compare our proposals to the best known opportunistic method, and show that they provide much greater power savings inflicting even lower delays to Internet traffic.
Molecular mechanisms underlying activity-dependent regulation of BDNF expression.

Activity-dependent changes in synaptic strength, which appear to underlie cortical plasticity, require long-lasting biochemical changes in the postsynaptic neuron. An inductive event common to several forms of synaptic plasticity is an influx of calcium into the postsynaptic cell. Calcium acts as a second messenger to set into motion a cascade of biochemical signaling events that leads to new gene expression. Brain-derived neurotrophic factor (BDNF) is one such calcium-regulated gene that appears to be involved in activity-dependent cortical plasticity. Studies of the mechanism by which calcium influx induces BDNF expression have revealed that the BDNF promoter is regulated by two calcium response elements. One of the elements appears to be regulated by a novel transcription factor, while the other element is regulated by the previously characterized transcription factor CREB. The calcium signal is propagated to the CREB-mediated component of BDNF expression by CaM kinase IV. This signaling pathway, which links calcium influx to the induction of BDNF via CaM kinase IV and CREB, is likely to be centrally involved in mediating long-term activity-dependent plasticity.
Preparation and characterization of candidate reference materials for telomerase assays.

BACKGROUND Telomerase has been measured in body fluids of cancer patients, and clinical tests for telomerase may have utility as noninvasive, cost-effective methods for the early detection of cancer. However, telomerase activity measured by common methods such as the telomerase repeat amplification protocol (TRAP) and telomerase reverse transcriptase catalytic subunit (hTERT) mRNA by reverse transcription-PCR (RT-PCR) varies among laboratories. METHODS We prepared a CHAPS buffer lysate from cultured A549 cells and stored it at -80 degrees C. Telomerase activity was measured by TRAP/PCR and real-time TRAP/PCR in conjunction with RT-PCR measurements of hTERT mRNA. Activity measured with use of the robot-assisted TRAP (RApidTRAP) multicapillary electrophoresis system was compared with single-capillary and slab-gel measurements in the range 10 to 10 000 cell equivalents. RESULTS Preparations made after flash freezing and sonication of cells were approximately 3-fold more active. Although the slab-gel and capillary instruments detected telomerase activity, the multicapillary instrument was better suited for high-throughput studies. Measurements of telomerase by TRAP/real-time PCR and hTERT mRNA/RT-PCR yielded reproducible titrations in the range 10 to 10 000 cell equivalents (CVs, 1%-8% and 1%-3%, respectively). CONCLUSIONS We have prepared and characterized a candidate reference material that appears to be suitable for use in a wide range of assays of telomerase activity and expression.
Cognitive Impairment and Age-Related Vision Disorders: Their Possible Relationship and the Evaluation of the Use of Aspirin and Statins in a 65 Years-and-Over Sardinian Population

Neurological disorders (Alzheimer’s disease, vascular and mixed dementia) and visual loss (cataract, age-related macular degeneration, glaucoma, and diabetic retinopathy) are among the most common conditions that afflict people of at least 65 years of age. An increasing body of evidence is emerging, which demonstrates that memory and vision impairment are closely, significantly, and positively linked and that statins and aspirin may lessen the risk of developing age-related visual and neurological problems. However, clinical studies have produced contradictory results. Thus, the intent of the present study was to reliably establish whether a relationship exist between various types of dementia and age-related vision disorders, and to establish whether statins and aspirin may or may not have beneficial effects on these two types of disorders. We found that participants with dementia and/or vision problems were more likely to be depressed and displayed worse functional ability in basic and instrumental activities of daily living than controls. Mini mental state examination scores were significantly lower in patients with vision disorders compared to subjects without vision disorders. A closer association with macular degeneration was found in subjects with Alzheimer’s disease than in subjects without dementia or with vascular dementia, mixed dementia, or other types of age-related vision disorders. When we considered the associations between different types of dementia and vision disorders and the use of statins and aspirin, we found a significant positive association between Alzheimer’s disease and statins on their own or in combination with aspirin, indicating that these two drugs do not appear to reduce the risk of Alzheimer’s disease or improve its clinical evolution and may, on the contrary, favor its development. No significant association in statin use alone, aspirin use alone, or the combination of these was found in subjects without vision disorders but with dementia, and, similarly, none in subjects with vision disorders but without dementia. Overall, these results confirm the general impression so far; namely, that macular degeneration may contribute to cognitive disorders (Alzheimer’s disease in particular). In addition, they also suggest that, while statin and aspirin use may undoubtedly have some protective effects, they do not appear to be magic pills against the development of cognitive impairment or vision disorders in the elderly.
Effects of Feeding Varying Concentrations of Dry Distiller's Grains with Solubles to Finishing Steers on Feedlot Performance, Nutrient Management and Odorant Emissions

A study was conducted to determine the effects of feeding varying concentrations of dried distillers grains with solubles (DDGS) to finishing steers on feedlot performance, nutrient management, and odorant emissions. Prior to initiation of the trial, 192 steers (initial BW = 826 ± 18 lb) were blocked by receiving date, weighed, and randomly allotted to 16 dirt floor pens (48.2 ft x 113.8 ft; 5% slope). Pens were then randomly assigned to one of four dietary treatments. The control diet (CON) contained 82% cracked corn, 10% alfalfa hay, 4% molasses, 3.2% supplement, and 0.8% urea. In the remaining three treatment diets, all of the urea and portions of the cracked corn were removed and replaced with DDGS at 15% (15% DDGS), 25% (25% DDGS), and 35% (35% DDGS) of the diet DM. The diets were formulated to be isocaloric and to provide similar levels of crude protein (CP) for CON and 15% DDGS (13.2 and 13.3% CP, respectively) and a stepwise increase in CP for 25% and 35% DDGS (15.4 and 17.6%, respectively). Analysis of weekly feed samples collected throughout the trial determined that the CP concentrations were 11.4, 12.2, 14.3, and 16.5% for CON, 15% DDGS, 25% DDGS, and 35% DDGS, respectively.
Identifying the Viral Genes Encoding Envelope Glycoproteins for Differentiation of Cyprinid herpesvirus 3 Isolates

Cyprinid herpes virus 3 (CyHV-3) diseases have been reported around the world and are associated with high mortalities of koi (Cyprinus carpio). Although little work has been conducted on the molecular analysis of this virus, glycoprotein genes identified in the present study seem to be valuable targets for genetic comparison of this virus. Three envelope glycoprotein genes (ORF25, 65 and 116) of the CyHV-3 isolates from the USA, Israel, Japan and Korea were compared, and interestingly, sequence insertions or deletions were observed in these target regions. In addition, polymorphisms were presented in microsatellite zones from two glycoprotein genes (ORF65 and 116). In phylogenetic tree analysis, the Korean isolate was remarkably distinguished from USA, Israel, Japan isolates. These findings may be suitable for many applications including isolates differentiation and phylogeny studies.
Components of courage in chronically ill adolescents: a phenomenological study

Although courage is an important variable when clients successfully deal with hospitalization and illness, the concept is contradictory and ill-defined in nursing and other literature. The phenomenological approach and research method has been suggested as one means of concept clarification and theory development. Using the phenomenological approach, this study asked: What is the essential structure of the lived experience of courage in chronically ill adolescents? Nine chronically ill adolescents participated in an open-ended, audiotape-recorded interview, describing their subjective experiences of courage. The descriptions were analyzed phenomenologically. Significant statements were extracted, meanings formulated, and themes identified. Thirty-one theme clusters in nine categories emerged from which an essential structure of courage in chronically ill adolescents was derived.
Temperament: a consideration of concepts and methods.

This paper discusses conceptual issues and begins with a consideration of definitions of temperament. It is suggested that the purposes for which temperament has been studied have, to some degree, dictated methods used and inferences drawn. Those psychopathologists interested in the relationship between temperament and psychiatric disorder, or emotional and behavioural disturbance, have tended to use different methods from those more concerned with delineating the structure of personality. Some issues and problems are common to both approaches, e.g. the definition of behaviour reflecting temperament in terms of style rather than content. Other issues, such as the difficulty involved in drawing a clear distinction between temperamental attributes and mental disorders, are restricted to one approach. The relative contribution of gentic and environmental effects is of interest to both psychopathologists (who wish to examine this issue in relation to the development of the individual), and to psychologists (who are usually more concerned with populations or aggregate effects). The application of biometric genetic models might clarify this issue, and various suggestions are made regarding steps that need to be taken if such models are to be successfully applied.
Dietary antioxidants protect gut epithelial cells from oxidant-induced apoptosis

Background: The potential of ascorbic acid and two botanical decoctions, green tea and cat's claw, to limit cell death in response to oxidants were evaluated in vitro. Methods: Cultured human gastric epithelial cells (AGS) or murine small intestinal epithelial cells (IEC-18) were exposed to oxidants – DPPH (3 μM), H2O2 (50 μM), peroxynitrite (300 μM) – followed by incubation for 24 hours, with antioxidants (10 μg/ml) administered as a 1 hour pretreatment. Cell number (MTT assay) and death via apoptosis or necrosis (ELISA, LDH release) was determined. The direct interactions between antioxidants and DPPH (100 μM) or H2O2 (50 μM) were evaluated by spectroscopy. Results: The decoctions did not interact with H2O2, but quenched DPPH although less effectively than vitamin C. In contrast, vitamin C was significantly less effective in protecting human gastric epithelial cells (AGS) from apoptosis induced by DPPH, peroxynitrite and H2O2 (P < 0.001). Green tea and cat's claw were equally protective against peroxynitrite and H2O2, but green tea was more effective than cat's claw in reducing DPPH-induced apoptosis (P < 0.01). Necrotic cell death was marginally evident at these low concentrations of peroxynitrite and H2O2, and was attenuated both by cat's claw and green tea (P < 0.01). In IEC-18 cells, all antioxidants were equally effective as antiapoptotic agents. Conclusions: These results indicate that dietary antioxidants can limit epithelial cell death in response to oxidant stress. In the case of green tea and cat's claw, the cytoprotective response exceed their inherent ability to interact with the injurious oxidant, suggestive of actions on intracellular pathways regulating cell death. Introduction Epithelial apoptosis in the gastro-intestinal tract is normally restricted to superficial cells but in pathological states of inflammation or infection, apoptotic cell death can be far more expansive. Under these conditions apoptosis may result from the production of cytokines [1], cell Published: 10 December 2001 BMC Complementary and Alternative Medicine 2001, 1:11 Received: 6 April 2001 Accepted: 10 December 2001 This article is available from: http://www.biomedcentral.com/1472-6882/1/11 © 2001 Miller et al; licensee BioMed Central Ltd. Verbatim copying and redistribution of this article are permitted in any medium for any non-commercial purpose, provided this notice is preserved along with the article's original URL. For commercial use, contact info@biomedcentral.com
An elementary construction of constant-degree expanders

We describe a short and easy to analyze construction of constant-degree expanders. The construction relies on the replacement product, applied by [14] to give an iterative construction of bounded-degree expanders. Here we give a simpler construction, which applies the replacement product (only twice! ) to turn the Cayley expanders of [4], whose degree is polylog n, into constant degree expanders. This enables us to prove the required expansion using a new simple combinatorial analysis of the replacement product (instead of the spectral analysis used in [14]).
Model-driven automation for simulation-based functional verification

Developing testbenches for dynamic functional verification of hardware designs is a software-intensive process that lies on the critical path of electronic system design. The increasing capabilities of electronic components is contributing to the construction of complex verification environments that are increasingly difficult to understand, maintain, extend, and reuse across projects. Model-driven software engineering addresses issues of complexity, productivity, and code quality through the use of high-level system models and subsequent automatic transformations. Reasoning about verification testbench decomposition becomes simpler at higher levels of abstraction. In particular, the aspect-oriented paradigm, when applied at the model level, can minimize the overlap in functionality between modules, improving maintainability and reusability. This article presents an aspect-oriented model-driven engineering process and toolset for the development of hardware verification testbenches. We illustrate how this process and toolset supports modularized design and automatic transformation to verification environment-specific models and source code through an industry case study.
Design of quantizers for decentralized estimation systems

The authors consider parameter estimation in decentralized systems with distributed processors. They restrict the local processors to be quantizers and consider the optimal design of the systems to minimize the estimation error. They present necessary conditions for the optimal system based on the Bayes distortion functions and Fisher's information. The numerical results compare the resulting quantizers obtained by different distortion criteria. >
Claisen rearrangement of graphite oxide: a route to covalently functionalized graphenes.

The chemical modification of nano- or micro-molecular surfaces is widely used for the precise structural and/or electrical manipulation of bulk materials. [1] In particular, atomically thin graphitic molecules such as fullerene, carbon nanotubes, and graphene display pronounced physicochemical and electronic changes after synthetic derivatization of their surfaces. [2] In many cases these graphitic substrates can be imbued with a wide range of desirable attributes such as increased solubility in a specific solvent, enhanced mechanical properties, chemosensing, and conductance changes. Because of these attributes, numerous prepared graphitic derivatives have been utilized in a variety of academic and industrial applications. [3] Unfortunately, few synthetic methods currently exist to covalently functionalize the surface of graphene. [4] This deficiency is due to both the use of meta-stable colloidal suspensions of reduced graphite oxide (GO) as the starting material for many transformations, [5] as well as the decreased chemical reactivity of graphene in comparison to the more strained fullerene or carbon nanotubes. [6],[7] Herein we report the covalent functionalization of soluble, exfoliated graphite oxide through a Claisen rearrangement (Scheme 1). Specifically, the allylic alcohol functional groups found on the surface of GO, [8] are converted in-situ to vinyl allyl ethers, and allylically transposed in a sigmatropic-type fashion to form new carbon-carbon bonds. As a direct result of this transformation robust carbonyls are installed on the surface, which can undergo subsequent synthetic manipulations. The Eschenmoser-Claisen rearrangement variant was chosen as the proof of test reaction on GO (Scheme 1, where R = N(CH 3 ) 2 ). In this reaction allylic alcohols are converted to γ , δ unsaturated on graphite oxide, the allylic alcohol surface functional groups were directly converted to carbon-bound N,N-dimethylamide groups through the use of the reagent DMDA. [25] These amide groups, when saponified under strongly basic conditions, were converted to the corresponding carboxylates, which have been shown to dramatically increase the solubility of the graphene derivative in aqueous environments without the need of co-solvents or additives. [26] Current efforts are underway to expand the scope and application of this transformation and to investigate the possibility of additional Claisen rearrangements on graphitic substrates. A one-pot, oxygen to carbon bond allylic transposition reaction and chemical reduction of graphite oxide has been demonstrated. Utilizing N,N-dimethylacetamide dimethylacetal, the basal plane allylic alcohol functionality of graphite oxide can be converted to N,N-dimethylamide groups through an Eschenmoser-Claisen sigmatropic-type rearrangement. These groups can be subsequently saponified to the carboxylic acid, which, when deprotonated, electrostatically stabilizes the graphene sheets in an aqueous environment.