gebhart/patrepeval huggingface dataset:
A dynamic model of the cardiac ventricular action potential. I. Simulations of ionic currents and concentration changes. (1994)

A mathematical model of the cardiac ventricular action potential is presented. In our previous work, the membrane Na+ current and K+ currents were formulated. The present article focuses on processes that regulate intracellular Ca2+ and depend on its concentration. The model presented here for the mammalian ventricular action potential is based mostly on the guinea pig ventricular cell. However, it provides the framework for modeling other types of ventricular cells with appropriate modifications made to account for species differences. The following processes are formulated: Ca2+ current through the L-type channel (ICa), the Na(+)-Ca2+ exchanger, Ca2+ release and uptake by the sarcoplasmic reticulum (SR), buffering of Ca2+ in the SR and in the myoplasm, a Ca2+ pump in the sarcolemma, the Na(+)-K+ pump, and a nonspecific Ca(2+)-activated membrane current. Activation of ICa is an order of magnitude faster than in previous models. Inactivation of ICa depends on both the membrane voltage and [Ca2+]i. SR is divided into two subcompartments, a network SR (NSR) and a junctional SR (JSR). Functionally, Ca2+ enters the NSR and translocates to the JSR following a monoexponential function. Release of Ca2+ occurs at JSR and can be triggered by two different mechanisms, Ca(2+)-induced Ca2+ release and spontaneous release. The model provides the basis for the study of arrhythmogenic activity of the single myocyte including afterdepolarizations and triggered activity. It can simulate cellular responses under different degrees of Ca2+ overload. Such simulations are presented in our accompanying article in this issue of Circulation Research.
Computer‐based learning: Interleaving whole and sectional representation of neuroanatomy (2012)

The large volume of material to be learned in biomedical disciplines requires optimizing the efficiency of instruction. In prior work with computer-based instruction of neuroanatomy, it was relatively efficient for learners to master whole anatomy and then transfer to learning sectional anatomy. It may, however, be more efficient to continuously integrate learning of whole and sectional anatomy. A study of computer-based learning of neuroanatomy was conducted to compare a basic transfer paradigm for learning whole and sectional neuroanatomy with a method in which the two forms of representation were interleaved (alternated). For all experimental groups, interactive computer programs supported an approach to instruction called adaptive exploration. Each learning trial consisted of time-limited exploration of neuroanatomy, self-timed testing, and graphical feedback. The primary result of this study was that interleaved learning of whole and sectional neuroanatomy was more efficient than the basic transfer method, without cost to long-term retention or generalization of knowledge to recognizing new images (Visible Human and MRI).
Atomic Force Microscopy and Kelvin Probe Force Microscopy Evidence of Local Structural Inhomogeneity and Nonuniform Dopant Distribution in Conducting Polybithiophene (1996)

Direct evidence of local structural inhomogeneity and nonuniform doping-level distribution in conducting polymer film has been obtained using Kelvin probe force microscopy (KFM) and atomic force microscopy (AFM). The KFM data suggests that the polymer consists of grains that constantly differ in work function and thus in the dopant concentration from the grain peripheral regions. For the as-grown polymer, most of the doping charge is located at the grain tops, whereas the electrochemically doped polymer features relatively higher doped grain periphery and less doped grain tops. The AFM study reveals two different kinds of the polymer molecular structure dependent on whether the image was taken at the top of a grain or the grain periphery. This result confirms the inherent inhomogeneity of conducting polymers demonstrated with KFM.
Can renal dysfunction after infra-renal aortic aneurysm repair be modified by multi-antioxidant supplementation? (2002)

The results indicate that the diminished renal function after infrarenal aneurysm repair may be influenced by antioxidant therapy.
Plasma concentrations of testosterone, dihydrotestosterone, Δ4-androstenedione, dehydroepiandrosterone and oestradiol-17β in the crabeating monkey ( <i>Macaca fascicularis</i> ) from birth to adulthood (1985)

Plasma testosterone, 5 alpha-dihydrotestosterone (DHT), delta 4-androstenedione, dehydroepiandrosterone (DHA) and oestradiol-17 beta concentrations of crab-eating macaques after birth were analysed by RIA. The profiles of plasma testosterone and DHT exhibited four phases: (1) a neonatal phase (0 to 3-4 months of age) with considerable synthetic testicular activity; (2) a phase of 'infancy' (generally up to 29 months of age) during which the values of both androgens were low; (3) a prepubertal phase (generally up to 43 months of age) when circulating values oscillated with wider individual variations, and (4) a pubertal phase when the concentrations increased in parallel and concomittantly with the onset of meiosis and the establishment of spermatogenesis. The testosterone values continued to increase, reaching adult values at about 5-6 years of age, whereas DHT levels tended to stabilize from 4-5 years. Relatively high androstenedione values during the neonatal phase decreased progressively until puberty, then increased again slowly up to the adult stage when they plateaued at about neonatal levels. The DHA levels were high during the first months, decreased at about 1 year, remained stable during infancy and prepuberty and then declined again during puberty. At about 5 years, the values were 28% of those in neonates. There was no evidence of an adrenarche before the first signs of sexual maturity were observed. Oestradiol-17 beta concentrations were high at birth and until 3 months, then decreased and remained steady from 1 year of age until adulthood, except at the onset of puberty (27-30 months of age) when high values were again noted. Our results show that, during the neonatal period, the testis exhibited considerable secretory activity.
Research on Electronic Commercial (2014)

With the advent of the era of economic globalization and Internet information and the emergence of this emerging industry, e-commerce for modern business provides a completely new business platform, which has played a tremendous economic significance in promoting the potential engine of global growth for small and medium-sized enterprise's survival and development. The paper analyzed the current developing model and innovation of electronic commerce in our country’s small and medium-sized enterprises.
Distinct cortical migrations from the medial and lateral ganglionic eminences (2001)

Recent evidence suggests that projection neurons and interneurons of the cerebral cortex are generally derived from distinct proliferative zones. Cortical projection neurons originate from the cortical ventricular zone (VZ), and then migrate radially into the cortical mantle, whereas most cortical interneurons originate from the basal telencephalon and migrate tangentially into the developing cortex. Previous studies using methods that label both proliferative and postmitotic cells have found that cortical interneurons migrate from two major subdivisions of the developing basal telencephalon: the medial and lateral ganglionic eminences (MGE and LGE). Since these studies labeled cells by methods that do not distinguish between the proliferating cells and those that may have originated elsewhere, we have studied the contribution of the MGE and LGE to cortical interneurons using fate mapping and genetic methods. Transplantation of BrdU-labeled MGE or LGE neuroepithelium into the basal telencephalon of unlabeled telencephalic slices enabled us to follow the fate of neurons derived from each of these primordia. We have determined that early in neurogenesis GABA-expressing cells from the MGE tangentially migrate into the cerebral cortex, primarily via the intermediate zone, whereas cells from the LGE do not. Later in neurogenesis, LGE-derived cells also migrate into the cortex, although this migration occurs primarily through the subventricular zone. Some of these LGE-derived cells invade the cortical plate and express GABA, while others remain within the cortical proliferative zone and appear to become mitotically active late in gestation. In addition, by comparing the phenotypes of mouse mutants with differential effects on MGE and LGE migration, we provide evidence that the MGE and LGE may give rise to different subtypes of cortical interneurons.
<i>In vivo</i> nanomechanical imaging of blood-vessel tissues directly in living mammals using atomic force microscopy (2009)

Atomic force microscopy (AFM) is difficult to achieve in living mammals but is necessary for understanding mechanical properties of tissues in their native form in organisms. Here we report in vivo nanomechanical imaging of blood-vessel tissues directly in living mammalians by AFM combined with surgical operations. Nanomechanical heterogeneity of blood vessels is observed across the diverse microenvironments of the same tissues in vivo. This method is further used to measure the counteractive nanomechanical changes in real time during drug-induced vasodilation and vasoconstriction in vivo, demonstrating appealing potential in characterization of in vivo nanomechanical dynamics of native tissues.
Nonlinear effects in optical fibres and fibre devices (1987)

We review experimental and theoretical work on the effects of the Kerr nonlinearity in optical fibres. The nonlinear Schrodinger equation is introduced and its solutions are discussed. The effects of perturbations both to the initial pulse and to the equation demonstrate the stability of solitons. Applications of this work include pulse compression and the soliton laser. Finally we discuss recent work on the modification of the linear guiding properties at high intensities.
Maximum Entropy Inverse Reinforcement Learning (2018)

Recent research has shown the beneﬁt of framing problems of imitation learning as solutions to Markov Decision Problems. This approach reduces learning to the problem of re- covering a utility function that makes the behavior induced by a near-optimal policy closely mimic demonstrated behavior. In this work, we develop a probabilistic approach based on the principle of maximum entropy. Our approach provides a well-deﬁned, globally normalized distribution over decision sequences, while providing the same performance guarantees as existing methods. We develop our technique in the context of modeling real world navigation and driving behaviors where collected data is inherently noisy and imperfect. Our probabilistic approach enables modeling of route preferences as well as a powerful new approach to inferring destinations and routes based on partial trajectories.
Studies on the Chemical Stability and Functional Group Compatibility of the Benzoin Photolabile Safety-Catch Linker Using an Analytical Construct (2001)

A chemical stability study of the benzoin photolabile safety-catch linker (BPSC) has been carried out using a dual-linker analytical construct to establish its compatibility with a range of commonly employed solid-phase reaction conditions. As a result of this study, the dithiane-protected benzoin linker was shown to be reactive only toward strong acids and fluoride nucleophile. Furthermore, a scan of diverse functional groups thought to be unstable toward the safety-catch removal conditions has also been carried out. These data should provide assistance in future utilization of the BPSC for syntheses.
Mechanisms of Intermittent Ventricular Bigeminy (1955)

In order to analyze the cause for the appearance and disappearance of ventricular premature systoles giving rise to temporary bigeminal rhythm, the electrocardiographic material was divided into two major groups: group A, consisting of ectopic beats with fixed coupling occurring during grossly irregular dominant rhythms, and group B, consisting of ectopic beats with varying coupling occurring during regular dominant rhythms. Analysis of group A, the subject of the present report, shows a definite relationship between the duration of the ventricular cycle and the occurrence of ventricular premature systoles, in that long cycles favor their appearance whereas short cycles tend to preclude it. This "rule of bigeminy" is best explained on the basis of a re-entry mechanism of the ventricular premature systoles. Criteria are given for the differential diagnosis between ventricular premature systoles and aberrant ventricular conduction of supraventricular impulses which is prone to occur under similar circumstances. The analysis of group B is presented in a subsequent report.
Methods of high efficiency compression for transmission of spatial representation of motion scenes (2015)

The paper reports the hitherto obtained results of the research project that deals with scene representations that are suitable for free navigation around the scene. These scene representations are acquired from a limited number of cameras located around the scene. The project is aimed at the development of an efficient compression technology and the experimental environment for testing such technology. The paper reports some new multiview test sequences with the circular camera arrangement, including the hybrid ones that have been acquired using also the depth sensors. Finally, the paper also briefly reports the recent results of the new compression technology being under development. This technology outperforms the state-of-the-art 3D-HEVC.
The Signaling Network of Transforming Growth Factor β1, Protein Kinase Cδ, and Integrin Underlies the Spreading and Invasiveness of Gastric Carcinoma Cells (2005)

Integrin-mediated cell adhesion and spreading enables cells to respond to extracellular stimuli for cellular functions. Using a gastric carcinoma cell line that is usually round in adhesion, we explored the mechanisms underlying the cell spreading process, separate from adhesion, and the biological consequences of the process. The cells exhibited spreading behavior through the collaboration of integrin-extracellular matrix interaction with a Smad-mediated transforming growth factor beta1 (TGFbeta1) pathway that is mediated by protein kinase Cdelta (PKCdelta). TGFbeta1 treatment of the cells replated on extracellular matrix caused the expression and phosphorylation of PKCdelta, which is required for expression and activation of integrins. Increased expression of integrins alpha2 and alpha3 correlated with the spreading, functioning in activation of focal adhesion molecules. Smad3, but not Smad2, overexpression enhanced the TGFbeta1 effects. Furthermore, TGFbeta1 treatment and PKCdelta activity were required for increased motility on fibronectin and invasion through matrigel, indicating their correlation with the spreading behavior. Altogether, this study clearly evidenced that the signaling network, involving the Smad-dependent TGFbeta pathway, PKCdelta expression and phosphorylation, and integrin expression and activation, regulates cell spreading, motility, and invasion of the SNU16mAd gastric carcinoma cell variant.
Structure of a split yeast gene: complete nucleotide sequence of the actin gene in Saccharomyces cerevisiae. (1980)

The complete nucleotide sequence of the actin gene from Saccharomyces cerevisiae has been determined. The coding region is interrupted by a 304-base-pair intervening sequence that is located within the triplet coding for amino acid 4. DNA sequences of the intron-exon junctions are similar to those found in higher eukaryotes and can be aligned such that the intron starts with the dinucleotide 5'-G-T-3' and ends with 5'-A-G-3'. Regions fo homology within the sequences upstream from the initiation codon and those following the termination codon have been detected between the yeast iso-1-cytochrome c gene and the actin gene. As deduced from the nucleotide sequence, yeast actin has 374 amino acid residues. Its primary structure, especially the NH2-terminal third of the protein, is highly conserved during evolution.
Fast high‐resolution <i>T</i><sub>1</sub> mapping of the human brain (2005)

A sequence for the acquisition of high-resolution T1 maps, based on magnetization-prepared multislice fast low-angle shot (FLASH) imaging, is presented. In contrast to similar methods, no saturation pulses are used, resulting in an increased dynamic range of the relaxation process. Furthermore, it is possible to acquire data during all relaxation delays because only slice-selective radiofrequency (RF) pulses are used for inversion and excitation. This allows for a reduction of the total acquisition time, or scanning with a reduced bandwidth, which improves the signal-to-noise ratio (SNR). The method generates quantitative T1 maps with an in-plane resolution of 1 mm, slice thickness of 4 mm, and whole-brain coverage in a clinically acceptable imaging time of about 19 s per slice. It is shown that the use of off-center RF pulses does not result in imperfect inversion or magnetization transfer (MT) effects. In addition, an improved fitting algorithm based on smoothed flip angle maps is presented and tested successfully.
DIRECT AND ASSOCIATE EFFECTS OF BODY WEIGHT AND VIABILITY IN <i> DROSOPHILA MELANOGASTER</i> (1970)

HEN genotypes coexist in a common environment, the genotypes interaot W i n l a variety of ways. Probably the most frequently observed interaction is that of competition, where the success of some genotypes results in a failure of others. Competition among genotypes in Drosophila has been investigated by many workers. For example, DOBZHANSKY (1 950) found changes in adaptive values of different chromosome arrangements when the genotypes were reared together in crowded conditions; LEWONTIN (1955) and LEWONTIN and MATSUO (1963) found competition affecting larval viability among different genotypes in Drosophila melanogaster and Drosophila buskii, respectively; MATHER and COOK (1962) reponted competition among different lines of D. melanogaster affecting sternopleural chaetae numbers.
Apaf1 plays a negative regulatory role in T cell responses by suppressing activation of antigen-stimulated T cells (2018)

Apaf1 is a critical component of the apoptosome and initiates apoptosis downstream mitochondrial damages. Although the importance of Apaf1 in embryonic development was shown, the role of Apaf1 in immune responses, especially T cell responses, has yet to be elucidated. We generated T cell-specific Apaf1-deficient mice (Lck-Cre-Apaf1f/f mice) and examined the antigen-specific delayed-type hypersensitivity (DTH). Lck-Cre-Apaf1f/f mice exhibited exacerbation of DTH responses as compared with Apaf1-sufficient control mice. In Lck-Cre-Apaf1f/f mice, antigen-specific T cells proliferated more, and produced more inflammatory cytokines than control T cells. Apaf1-deficient T cells from antigen-immunized mice showed higher percentages of activation phenotypes upon restimulation in vitro. Apaf1-deficient T cells from naive (non-immunized) mice also showed higher proliferation activity and cytokine production over control cells. The impact of Apaf1-deficiency in T cells, however, was not restored by a pan-caspase inhibitor, suggesting that the role of Apaf1 in T cell responses was caspase-independent/non-apoptotic. These data collectively demonstrated that Apaf1 is a negative regulator of T cell responses and implicated Apaf1 as a potential target for immunosuppressive drug discovery.
Robust and Biocompatible Hybrid Matrix with Controllable Permeability for Microalgae Encapsulation (2016)

Hybrid beads with entrapped microalgae Chlamydomonas reinhardtii were synthesized for the sustainable production of high value metabolites via photosynthesis. Encapsulating the microalgae requires an exquisite control of material properties, which has been achieved by modifying the composition (alginate, polycation, and silica). A coating of PDADMAC precluded cell leakage as indicated by the OD750 value of the culture medium, and the homogeneous distribution of silica prevented bead shrinkage from the strong electronic force of PDADMAC, resulting in a robust and biocompatible matrix for the cells. Besides fabricating suitable porous beads for the diffusion of expected metabolites, the permeability can be controlled to a certain degree by applying different molecular weights of PDADMAC. The hybrid alginate+silica/CaCl2+PDADMAC beads possessed sufficient mechanical rigidity to sheer force under constant stirring and good chemical stability to chelating agents such as sodium citrate. Moreover, the encapsulated cells exhibited excellent long-term viability and cellular functionality, which retained about 81.5% of the original value after a 120 day encapsulation as observed by microscopy and oximetry measurement. This study is not only significant for understanding the critical role of polycations and silica involved in the synthesis of hybrid beads but also important for real-scale bioengineering applications.
Possibilities of immunotherapy and gene therapy for malignant melanoma. (1993)

Over the last decade, both immunotherapy and gene therapy have emerged as exciting new modalities in the treatment of malignant melanoma. The fact that many melanoma patients mount cellular and humoral responses against their tumors, and that melanomas express both HLA antigens and tumor-associated antigens (TAA), has led to an increased interest in the treatment of melanoma by manipulation of the immune system. Advances have occurred in several areas, including a) the use of monoclonal antibodies, alone or in combination with cytokines, b) tumor vaccines, using whole cell preparations or cloned melanoma antigens, c) adoptive immunotherapy, with tumor-infiltrating lymphocytes (TILs) and cytotoxic T lymphocytes (CTLs), and d) gene therapy, designed to increase the immunogenicity of the tumor, increase the effectiveness of the TILs, or alter the basic mechanisms of tumor cell growth and regulation. Some of the advances in these areas are discussed.