gebhart/patrepeval huggingface dataset:
Automated in vivo segmentation of carotid plaque MRI with Morphology‐Enhanced probability maps (2006)

MRI is a promising noninvasive technique for characterizing atherosclerotic plaque composition in vivo, with an end-goal of assessing plaque vulnerability. Because of limitations arising from acquisition time, achievable resolution, contrast-to-noise ratio, patient motion, and the effects of blood flow, automatically identifying plaque composition remains a challenging task in vivo. In this article, a segmentation method using maximum a posteriori probability Bayesian theory is presented that divides axial, multi-contrast-weighted images into regions of necrotic core, calcification, loose matrix, and fibrous tissue. Key advantages of the method are that it utilizes morphologic information, such as local wall thickness, and coupled active contours to limit the impact from noise and artifacts associated with in vivo imaging. In experiments involving 142 sets of multi-contrast images from 26 subjects undergoing carotid endarterectomy, segmented areas of each of these tissues per slice agreed with histologically confirmed areas with correlations (R(2)) of 0.78, 0.83, 0.41, and 0.82, respectively. In comparison, manually identifying areas blinded to histology yielded correlations of 0.71, 0.76, 0.33, and 0.78, respectively. These results show that in vivo automatic segmentation of carotid MRI is feasible and comparable to or possibly more accurate than manual review for quantifying plaque composition.
Securing inter-cluster communication in Personal Networks (2007)

A Personal Network (PN) is a new type of an overlay network consisting of all personal devices belonging to a user, be they remote or local. Such continuous and seamless connectivity of all personal devices belonging to a user enables the development of new applications and improved services. A Personal Network is an intelligent and user-centric network that assists the user in an unobtrusive way. In this paper we investigate means of securing communication between geographically distributed Personal Network clusters. Clusters are ad-hoc networks of co-located personal devices. Using Virtual Private Network (VPN) technology enables the creation of secure tunnels between gateways of different clusters, making it possible to transfer all types of intra-cluster traffic securely, over the insecure public network. The ad-hoc nature of clusters when coupled with the mobile and resource constrained nature of many personal devices makes enforcing security a challenging task. We investigate the suitability of existing VPN technologies to secure inter-cluster communication. Our contribution is in identifying aspects of existing solutions that render them unsuitable in their current form for constrained personal devices. We propose a modified framework based on IPSec and KINK that better satisfies the requirements of personal devices by reducing the cost of security.
Capacity of a mobile multiple-antenna communication link in Rayleigh flat fading (1999)

We analyze a mobile wireless link comprising M transmitter and N receiver antennas operating in a Rayleigh flat-fading environment. The propagation coefficients between pairs of transmitter and receiver antennas are statistically independent and unknown; they remain constant for a coherence interval of T symbol periods, after which they change to new independent values which they maintain for another T symbol periods, and so on. Computing the link capacity, associated with channel coding over multiple fading intervals, requires an optimization over the joint density of T/spl middot/M complex transmitted signals. We prove that there is no point in making the number of transmitter antennas greater than the length of the coherence interval: the capacity for M>T is equal to the capacity for M=T. Capacity is achieved when the T/spl times/M transmitted signal matrix is equal to the product of two statistically independent matrices: a T/spl times/T isotropically distributed unitary matrix times a certain T/spl times/M random matrix that is diagonal, real, and nonnegative. This result enables us to determine capacity for many interesting cases. We conclude that, for a fixed number of antennas, as the length of the coherence interval increases, the capacity approaches the capacity obtained as if the receiver knew the propagation coefficients.
An approach to the design of molecular solids. Strategies for controlling the assembly of molecules into two-dimensional layered structures (1993)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAn approach to the design of molecular solids. Strategies for controlling the assembly of molecules into two-dimensional layered structuresYuh Loo Chang, Mary Ann West, Frank W. Fowler, and Joseph W. LauherCite this: J. Am. Chem. Soc. 1993, 115, 14, 5991–6000Publication Date (Print):July 1, 1993Publication History Published online1 May 2002Published inissue 1 July 1993https://pubs.acs.org/doi/10.1021/ja00067a014https://doi.org/10.1021/ja00067a014research-articleACS PublicationsRequest reuse permissionsArticle Views675Altmetric-Citations153LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (2)»Supporting Information Supporting Information Get e-Alerts
Cell Signaling and Trafficking of Human Melanocortin Receptors in Real Time Using Two‐photon Fluorescence and Confocal Laser Microscopy: Differentiation of Agonists and Antagonists (2006)

Melanocortin hormones and neurotransmitters regulate a vast array of physiologic processes by interacting with five G-protein-coupled melanocortin receptor types. In the present study, we have systematically studied the regulation of individual human melanocortin receptor wild subtypes using a synthetic rhodamine-labeled human melanotropin agonist and antagonist, arrestins fused to green fluorescent protein in conjunction with two-photon fluorescence laser scanning microscopy and confocal microscopy. Stimulation of the melanocortin receptors by its cognate agonist triggered rapid arrestin recruitment and receptor internalization for all four human melanocortin receptors examined. Antagonists-bound melanocortin receptors, on the other hand, did not recruit beta-arrestins, and remained in the cell membrane even after long-term (30 min) treatment. Agonist-mediated internalization of all melanocortin receptor subtypes was sensitive to inhibitors of clathrin-dependent endocytosis, but not to caveolae inhibitors. In summary, agonist-mediated internalization of all subtypes of melanocortin receptors are dependent upon beta-arrestin-mediated clathrin-coated pits, whereas, beta-arrestin-2 conjugated green fluorescence protein (beta-arrestin-2-GFP) recruitment is not dependent on protein kinase A activation. Real time two-photon fluorescence laser scanning microscopy is a most powerful tool to study the dynamic processes in living cells and tissues, without inflicting significant and often lethal damage to the specimen.
Grounded Situation Models for Robots: Where words and percepts meet (2006)

Our long-term objective is to develop robots that engage in natural language-mediated cooperative tasks with humans. To support this goal, we are developing an amodal representation and associated processes which is called a grounded situation model (GSM). We are also developing a modular architecture in which the GSM resides in a centrally located module, around which there are language, perception, and action-related modules. The GSM acts as a sensor-updated "structured blackboard", that serves as a workspace with contents similar to a "theatrical stage" in the robot's "mind", which might be filled in with present, past or imagined situations. Two main desiderata drive the design of the GSM: first, "parsing" situations into ontological types and relations that reflect human language semantics, and second, allowing bidirectional translation between sensory-derived data/expectations and linguistic descriptions. We present an implemented system that allows of a range of conversational and assistive behavior by a manipulator robot. The robot updates beliefs (held in the GSM) about its physical environment, the human user, and itself, based on a mixture of linguistic, visual and proprioceptive evidence. It can answer basic questions about the present or past and also perform actions through verbal interaction. Most importantly, a novel contribution of our approach is the robot's ability for seamless integration of both language- and sensor-derived information about the situation: for example, the system can acquire parts of situations either by seeing them or by "imagining" them through descriptions given by the user: "There is a red ball at the left". These situations can later be used to create mental imagery and sensory expectations, thus enabling the aforementioned bidirectionality
A possible mechanism of psoralen phototoxicity not involving direct interaction with DNA. (1985)

Psoralens in combination with ultraviolet light (UVA; 320-400 nm) are used in the photochemical treatment of a variety of skin diseases including vitiligo, a skin depigmentational disorder, and psoriasis, a disease of accelerated epidermal cell proliferation. Although it is generally assumed that the major site of action of the psoralens is DNA, we have obtained evidence that another site may be the primary target for these compounds. We have identified specific, saturable, high-affinity binding sites for 8-methoxypsoralen on HeLa cells and have detected specific binding of 8-methoxypsoralen to four other human cell lines and five mouse cell lines. In HeLa cells, specific binding is reversible and independent of the ability of the compound to intercalate into DNA. In addition, binding sites become covalently modified by the psoralen after UVA exposure. Specific binding of 8-[methoxy-3H]methoxypsoralen constitutes 79% of the label bound to the cells. Scatchard analysis indicated two classes of psoralen binding sites: high-affinity sites with a Kd of 19 X 10(-9) M (1.8 X 10(5) sites per cell) and low-affinity sites with a Kd of 4 X 10(-6) M (7.1 X 10(6) sites per cell). Four structurally related psoralen analogs block 8-methoxypsoralen binding in a manner that parallels their biological activity. Based on these findings, we hypothesize that specific binding sites for psoralens on mammalian cells mediate, at least in part, psoralen-induced phototoxicity.
Lipopolysaccharide or Whole Bacteria Block the Conversion of Inflammatory Monocytes into Dendritic Cells In Vivo (2003)

Monocytes can develop into dendritic cells (DCs) that migrate to lymph nodes (LNs) and present antigens to T cells. However, we find that this differentiation is blocked when monocytes accumulate subcutaneously in response to bacteria or lipopolysaccharide (LPS). The inhibition of DC differentiation is mediated by the bacteria and in conjunction with inflammatory cells recruited at the site of injection. Inhibition of migratory DC development was reversed in Toll-like receptor (TLR)4-mutated mice when LPS, but not whole bacteria, was injected, suggesting that TLR4 is one but not the only mediator of the inhibition. The block imposed by bacteria was partly relieved by the absence of interleukin (IL)-12 p40, but not by individual absence of several cytokines involved in DC differentiation or in inflammation, i.e., IL-6, IL-10, IL-12 p35, and interferon gamma. Consistent with the inability of monocytes to yield migrating DCs, and the finding that other DCs had limited access to particulate or bacterial antigens, these antigens were weakly presented to T cells in the draining LN. These results illustrate that bacteria-associated signals can have a negative regulatory role on adaptive immunity and that local innate responses for containment of infectious bacteria can at least initially supersede development of adaptive responses.
Association of Avian Reovirus M and S Genes with Viral Behavior in vivo. II. Viral Pathogenicity (1987)

A group of avian reoviruses comprising serially passaged S1133 strains and their vaccine derivatives was examined biochemically to study the temporal evolution of the viruses and biologically to assess their relative pathogenicities. The strains fell into three groups of differing virulence, the viruses becoming less pathogenic the longer they were passaged. Protein and RNA profiles of the strains showed no distinct patterns of evolution nor any trend that could be correlated with pathogenicity. Nucleic acid hybridization studies of the strains indicated that all the genes were altered to some extent during passage. The S1 and M3 genes appeared to change the most during the first half of passage history, but later, as the virus was cold-adapted or passaged extensively, the M2, S2, and S3 genes also appeared to vary. When viruses were grouped according to virulence, the greatest changes were seen in the S1, M2, and M3 genes, suggesting that these may be associated with the virulence of a given avian reovirus strain.
Superabsorbent Polymers (1994)

Models developed to describe free radical crosslinking polymerizations may be divided into three classes: statistical models, kinetic descriptions, and kinetic gelation simulations. This paper provides a comparison of the three types of models by describing the approach, assumptions, strengths, and limitations of each when applied to lightly crosslinked systems. The greatest strength of the statistical approach arises from the wealth of post-gel structural information that can be obtained, however these models have difficulty accounting for history-dependent effects. Kinetic descriptions may properly describe history-dependent reaction non-idealities, but are unable to account for localized effects that are prevalent in highly crosslinked systems. The kinetic gelation simulations may describe topological constraints and localized effects but are of limited use for lightly crosslinked polymers due to their inability to accurately account for molecular motions.
Alkene Chemoselectivity in Ruthenium‐Catalyzed Z‐Selective Olefin Metathesis (2013)

Chelated ruthenium catalysts can facilitate highly chemoselective olefin metathesis. Terminal and internal Z olefins reacted selectively to form new Z olefins in the presence of internal E olefins. Chemoselectivity for terminal olefins was also observed over both sterically hindered and electronically deactivated alkenes.
Inhibition of Lymphocyte Proliferation by a Synthetic Peptide Homologous to Retroviral Envelope Proteins (1985)

The retroviral transmembrane envelope protein p15E is immunosuppressive in that it inhibits immune responses of lymphocytes, monocytes, and macrophages. A region of p15E has been conserved among murine and feline retroviruses; a homologous region is also found in the transmembrane envelope proteins of the human retroviruses HTLV-I and HTLV-II and in a putative envelope protein encoded by an endogenous C-type human retroviral DNA. A peptide (CKS-17) was synthesized to correspond to this region of homology and was examined for its effects on lymphocyte proliferation. CKS-17 inhibited the proliferation of an interleukin-2-dependent murine cytotoxic T-cell line as well as alloantigen-stimulated proliferation of murine and human lymphocytes. Four other peptides, representing different regions of virus proteins, were inactive. These results suggest that the immunosuppressive portion of retroviral transmembrane envelope proteins may reside, at least in part, in a-conserved sequence represented by the CKS-17 peptide.
Progressive Multifocal Leukoencephalopathy in a Patient Treated with Natalizumab (2005)

We describe the clinical course of a patient with multiple sclerosis in whom progressive multifocal leukoencephalopathy (PML), an opportunistic viral infection of the central nervous system, developed during treatment with interferon beta-1a and a selective adhesion-molecule blocker, natalizumab. The first PML lesion apparent on magnetic resonance imaging was indistinguishable from a multiple sclerosis lesion. Despite treatment with corticosteroids, cidofovir, and intravenous immune globulin, PML progressed rapidly, rendering the patient quadriparetic, globally aphasic, and minimally responsive. Three months after natalizumab therapy was discontinued, changes consistent with an immune-reconstitution inflammatory syndrome developed. The patient was treated with systemic cytarabine, and two months later, his condition had improved.
Serous Cystadenoma of the Pancreas (2005)

Large (>4 cm) serous cystadenomas are more likely to be symptomatic. Although the median growth rate for this neoplasm is only 0.6 cm/y, it is significantly greater in large tumors. Whereas expectant management is reasonable in small asymptomatic tumors, we recommend resection for large serous cystadenomas regardless of the presence or absence of symptoms.
Low density lipoprotein receptor-binding activity in human tissues: quantitative importance of hepatic receptors and evidence for regulation of their expression in vivo. (1990)

The heparin-sensitive binding of 125I-labeled low-density lipoprotein (LDL) to homogenates from 18 different normal human tissues and some solid tumors was determined. The binding to adrenal and liver homogenates fulfilled criteria established for the binding of LDL to its receptor--namely, (i) saturability, (ii) sensitivity to proteolytic destruction, (iii) inhibition by EDTA, and (iv) heat sensitivity. When the binding of 125I-labeled LDL was assayed at a constant concentration (50 micrograms/ml), the adrenal gland and the ovary had the highest binding of normal tissues. The highest binding per g of tissue overall was obtained in homogenates of a gastric carcinoma and a parotid adenoma. When the weights of the parenchymatous organs were considered, the major amount of LDL receptors was contained in the liver. To study the possible regulation of hepatic LDL-receptor expression, 11 patients were pretreated with cholestyramine (8 g twice a day for 3 weeks). Increased binding activity (+105%, P less than 0.001) was obtained in homogenates from liver biopsies from the cholestyramine-treated patients as compared with 12 untreated controls. It is concluded that the liver is the most important organ for LDL catabolism in humans and that the receptor activity in this organ can be regulated upon pharmacologic intervention. Further studies are needed to confirm the possibility that certain solid tumors can exhibit high numbers of LDL receptors.
Regulation of carotenoid formation during tomato fruit ripening and development (2002)

Carotenoid biosynthesis and its regulation during tomato fruit development and ripening is a complex process that occurs alongside the differentiation of chloroplasts into chromoplasts and changes to the organoleptic properties of the fruit. Unusually for plants, the ripe tomato fruit accumulates large amounts of lycopene, as the pattern of gene expression found in green fruit changes during fruit ripening. Although the control of gene expression is thought to be the main regulatory mechanism for these alterations in carotenoids, post-transcriptional regulation has also been reported, including feedback inhibition. The use of genetic manipulation of carotenogenesis in tomato has been used primarily for biotechnological reasons, but it has also facilitated investigations into these regulatory mechanisms, as well as into the effects of such perturbations on other isoprenoids such as gibberellins, tocopherols and sterols.
Heat and moisture exchangers. Structure and function. (1998)

A bewildering array of HMEs are available, suited to many different tidal volume and other clinical requirements. Choosing among the different devices depends on many attributes. Grouping different HMEs together to describe their performance may be inappropriate. Independent tests on HMEs provide information to help when choosing among different devices, but care should be exercised to prevent inappropriate comparisons being made between results from studies using different test procedures and protocols. The use of filters in anesthesia is recommended in some countries. Some HMEs have a high moisture-conserving performance, but the use of HMEs may be inappropriate for some patient groups, and other humidifying devices may be more suitable.
The Use of MPSS for Whole-Genome Transcriptional Analysis in Arabidopsis (2004)

We have generated 36,991,173 17-base sequence "signatures" representing transcripts from the model plant Arabidopsis. These data were derived by massively parallel signature sequencing (MPSS) from 14 libraries and comprised 268,132 distinct sequences. Comparable data were also obtained with 20-base signatures. We developed a method for handling these data and for comparing these signatures to the annotated Arabidopsis genome. As part of this procedure, 858,019 potential or "genomic" signatures were extracted from the Arabidopsis genome and classified based on the position and orientation of the signatures relative to annotated genes. A comparison of genomic and expressed signatures matched 67,735 signatures predicted to be derived from distinct transcripts and expressed at significant levels. Expressed signatures were derived from the sense strand of at least 19,088 of 29,084 annotated genes. A comparison of the genomic and expression signatures demonstrated that approximately 7.7% of genomic signatures were underrepresented in the expression data. These genomic signatures contained one of 20 four-base words that were consistently associated with reduced MPSS abundances. More than 89% of the sum of the expressed signature abundances matched the Arabidopsis genome, and many of the unmatched signatures found in high abundances were predicted to match to previously uncharacterized transcripts.