cssi/SciSciGPT-SciSciNet huggingface dataset:
Ca2+ Release from Sarcoplasmic Reticulum in Muscle

Publisher Summary This chapter discusses Ca 2+ release from sarcoplasmic reticulum (SR) in muscles. The chapter focuses on voltage-dependent mechanism, and excitation-contraction (EC) coupling, which has been most thoroughly studied in vertebrate striated muscle. The chapter discusses several related concepts, including isolation and structure of ryanodine receptors (RyRs), molecular cloning and expression of RyRs, and RyRs as high-conductance ligand-gated channels. It is mentioned that mechanical coupling mechanism, has been formulated and suggests that the SR Ca 2+ release channel is opened via a direct physical interaction with a voltage-sensing molecule in the T-tubule. The identification of [ 3 H] ryanodine as a specific probe has enabled the isolation and subsequent cloning of a family of large intracellular channel complexes composed of four ∼560–kDa polypeptides. The chapter discusses the studies carried out to determine the structural and functional features of the SR RyR/Ca 2+ release channel. The mammalian RyRs are encoded by three different genes and show a tissue-specific expression. The three RyR isoforms are mentioned as skeletal muscle (RyR1), cardiac muscle (RyR2), and brain (RyR3) RyRs. They share several properties, including an apparent sedimentation coefficient of 30S, the presence of a high-affinity ryanodine binding site, and a high-conductance mono- and divalent-cation pathway that can be modified by ryanodine in an essentially identical manner. RyR/Ca 2+ release channels constitute a rich target for controlling cellular functions. A large number of endogenous effectors regulate RyR function, including Ca 2+ , Mg 2+ , ATP and calmodulin. RyRs also contain phosphorylation sites and reactive thiols, which suggests that receptor phosphorylation and reactive nitrogen and oxygen species have a role in the in vivo regulation of channel activity.
Novel joining of dissimilar ceramics in the Si3N4–Al2O3 system using polytypoid functional gradients

A unique approach to crack-free joining of heterogeneous ceramics is demonstrated by the use of sialon polytypoids as Functionally Graded Materials (FGM) as defined by the phase diagram in the system, Si3N4-Al2O3. Polytypoids in the Al2O3-Si3N4 system offer a path to compatibility for heterogeneous ceramics. This paper describes successful hot press sintering of multilayered FGM's with 20 layers of thickness 500 mm each. Transmission Electron Microscopy was used to identify the polytypoids at the interfaces of different areas of the joint. It has been found that the 15R polytypoid was formed in the Al2O3-contained layers and the 12H polytypoid was formed in the Si3N4-contained layers.
Evolution, Cooperation, and Repeated Games

I discuss recent work that characterizes what outcomes correspond to evolutionarily stable strategies in two-player symmetric repeated games when players have a positive probability of making a mistake.
Ziprasidone and cognition: the evolving story.

Cognitive impairment, a central characteristic of schizophrenia, can profoundly limit patients' ability to acquire or maintain skills needed for adequate functioning. Thus, research on the efficacy of antipsychotic medications is increasingly focusing on the possible benefits of these agents on cognitive function. Although data are limited, it appears that atypical antipsychotics consistently improve cognitive function to a greater extent than do older, conventional agents. This review focuses on the atypical agent ziprasidone and its effects on cognitive function. The most recent data on the cognitive effects of ziprasidone come from a comparative trial with olanzapine (40-80 mg b.i.d. and 5-15 mg q.d., respectively) and from 3 studies in which patients were switched to ziprasidone (40-160 mg/day) because of suboptimal efficacy or tolerability with other antipsychotics. In general, ziprasidone-treated patients demonstrated significant improvements in multiple cognitive domains--such as episodic memory, attention/vigilance, executive function, and visuomotor speed--that are generally associated with improved functional outcome. In the switching studies, path analysis indicated that improvement on the Positive and Negative Syndrome Scale (PANSS) cognitive subscale directly affected changes on the PANSS anxiety-depression cluster and a PANSS "prosocial" subscale composed of items related to social engagement. Improvement in cognitive function observed with ziprasidone may have implications for long-term patient outcomes.
Link Modeling with Joint Fading and Distance Uncertainty

We introduce and discuss a novel link model that incorporates both uncertainty in the fading coefficients and the node distances for ad hoc networks with randomly placed nodes. The main result is the complete distribution of the received power for a transmission between a node and its n-th nearest neighbor. Several applications of the proposed fading model are discussed, including connectivity, opportunistic communication, and localization.
CLASS AND ATTITUDES TOWARD STRUCTURAL INEQUALITIES: An Empirical Comparison of Key Variables in Neo- and Post-Marxist Scholarship

This article addresses a key issue within radical social science scholarship-the importance of class in modern capitalist society. Two different perspectives on the issue are discussed: the neo-Marxist, which continues to view class as the central structural variable; and the post-Marxist, which contends that other variables such as race, sex, and authority are potentially either additional or alternative structural influences. After developing a model linking structural locations to attitudinal consequences for position incumbents, two hypotheses comparing the perspectives are tested using a national sample of respondents: (1) that structural locations influence the attitudes of position incumbents toward societal inequalities; and (2) that the impact of a particular structural variable depends, at least to some extent, upon the nature of the societal inequality in question. The results provide qualified support for both hypotheses. The implications of these findings are discussed. Debate continues over the extent to which Marx's original conceptualization of classes as "positions within productive relations" applies to modern capitalist society. Within radical scholarship, two divergent perspectives on this issue have emerged. The first continues to view class as the central structural variable influencing the life-chances of the citizens of modem capitalist society. The second argues that the saliency of class has
Reversed remanent magnetic configuration in epitaxial La 1-x Sr x MnO 3 films

The polar discontinuity which can occur at oxide interfaces can modify the properties of oxide thin films. In such a system, an unusual reversed orientation of the remanent magnetic state was observed recently for La0.7Sr0.3MnO3 on Nb-doped SrTiO3(0 0 1) deposited via pulsed laser deposition (Lee et al 2010 Phys. Rev. Lett. 105 257204). Here, we report on a similar effect for La0.7Sr0.3MnO3 grown via molecular beam epitaxy, a deposition method with different growth kinetics, onto both Nb-doped and undoped SrTiO3 (STO) substrates. The reversed magnetic state occurred in both samples, while enriched Mn3+ regions (intermediate layer) are slightly different. Intriguingly, the onset of the reversed remanent state occurred at different temperatures: ~125 K for the Nb : STO substrate and ~240 K for the undoped STO substrate. Our results point to an additional mechanism for controlling the magnetism in mixed-valence oxide films.
REAL‐D: A Schema for Data Warehouses

This article integrates McCarthy's REA (Resources‐Events‐Agents) model and the closely related REAL (Resources Events Agents Locations) model with general capabilities and requirements of data warehouses. REA/REAL contribute a theory for capturing information about events and a focus on control relationships. Data warehouses bring time‐period information and a focus on information facilitating the creation of value. Using aspects from both camps, a hybrid schema is developed called REAL‐D, REAL for Data warehouses. Existing data warehouse approaches lack theory, while REA/REAL are theory based. Unique demands on data warehouses, however, make additional requirements on REA/REAL, including (1) addition of time period as another dimension in order to allow rollups from hour to day to week to month to year, (2) addition of location to facilitate rollups from office to city to district, (3) change from a pure location dimension to a nonhomogeneous dimension that allows rollup from person to office, and (4) ch...
Top management support for management science

Abstract Two aspects of the relation between top managers and in-house management science units are considered in this paper. First, the impact of top management sponsorship and support on the progress and success of management science (MS) activities is considered. Secondly, the impact that an MS activity has had on the thinking and activities of top managers is discussed. The question of the role of the “professional” in an organization and the implications for client-professional perceptions of trust as these are influenced by the top manager are explored. Top management awareness and utilization of the management sciences are also reviewed.
Taphonomy and taxonomy of a vertebrate microsite in the mid-Cretaceous (Albian-Cenomanian) Blackleaf Formation, southwest Montana

The vertebrate fauna of the Cretaceous Blackleaf Formation of southwest Montana remains largely undocumented. A microsite (BL1) discovered in the Flood Member in the Lima Peaks area, Montana, consists of a green siltstone and yields taxa previously unreported from the formation, including several dinosaurs: a hypsilophodont, dromaeosaurid, tyrannosauroid, hadrosaurid and an ankylosaurian. Non-dinosaurian taxa include goniopholidid and Bernissartia crocodilians; Glyptops, cf. chelydrid and other turtles and at least two neopterygiian fish. This diversity corresponds well with the fluvial–deltaic–estuarine environment interpreted for the uppermost unit of the Flood Member. Taphonomic data and sedimentologic relationships suggest that this assemblage represents a floodplain depression accumulation. Comparisons with contemporaneous faunas from around the Western Interior of the USA suggest a remarkably consistent faunal makeup, at least at the family level, existed across western North America in the mid-Cret...
Framing Comparative Risk: A Preliminary Analysis

ABSTRACT The ways in which journalists frame stories about disparity and inequality help to shape the ways in which the general public understands social problems. Increasingly stories about racial disparity are framed in terms of comparative risk. These stories consistently present an image of African Americans who are more likely to be victims or losers in some societal game of chance. Through an analysis of stories submitted for competitions among investigative journalists and their publishers, this article reveals the ways in which systematic editorial constraints appear across a broad range of story types. Despite what might be assumed to be an attempt by journalists to win sympathy for African Americans, these stories tend to blame these victims for their status. Although charges of institutional racism are relatively rare, this analysis also reveals that stories about racial disparity in the area of finances are far more likely to be framed in terms of discrimination than are stories in the area of...
Wear Characteristics of Binder-Less Nano-Polycrystalline Diamond and Cubic Boron Nitride

Wear characteristics of binder-less (single-phase) nanopolycrystalline diamond (NPD) and cubic boron nitride (BL-PcBN) were investigated by rubbing them against various ceramics such as SiO2, Si3N4, Al2O3 and SiC. The wear rates of NPD and BL-PcBN against SiO2 and Si3N4 at high speed rubbing (280-360 m/min) at a loading pressure of 55 MPa (starting condition) were considerably high, indicating the main wear process is a chemical reaction. BL-PcBN specimens were found to be worn at much higher (more than ten times) rates than NPD, suggesting that cBN highly reacts with these ceramics in comparison with diamond under the experiment condition.
NMF and PLSI: equivalence and a hybrid algorithm

In this paper, we show that PLSI and NMF optimize the same objective function, although PLSI and NMF are different algorithms as verified by experiments. In addition, we also propose a new hybrid method that runs PLSI and NMF alternatively to achieve better solutions.
CSI-SF: Estimating wireless channel state using CSI sampling & fusion

One of the key features of high speed WLAN such as 802.11n is the use of MIMO (Multiple Input Multiple Output) antenna technology. The MIMO channel is described with fine granularity by Channel State Information (CSI) that can be utilized in many ways to improve network performance. Many complex parameters of a MIMO system require numerous samples to obtain CSI for all possible channel configurations. As a result, measuring the complete CSI space requires excessive sampling overhead and thus degrades network performance. We propose CSI-SF (CSI Sampling & Fusion), a method for estimating CSI for every MIMO configuration by sampling a small number of frames transmitted with different settings and extrapolating data for the remaining settings. For instance, we predict CSI of multi-stream settings using CSI obtained only from single stream packets. We evaluate the effectiveness of CSI-SF in various scenarios using our 802.11n testbed and show that CSI-SF provides an accurate, complete knowledge of the MIMO channel with reduced overhead from traditional sampling. We also show that CSI-SF can be applied to network algorithms such as rate adaptation, antenna selection and association control to significantly improve their performance and efficiency.
Opposing microtubule- and actin-dependent forces in the development and maintenance of structural polarity in retinal photoreceptors.

We have used embryonic cells grown in vitro to study the roles of microtubules and microfilaments in the development and maintenance of the polarized shape of retinal photoreceptors. After several days in culture, isolated cone photoreceptors displayed a highly elongated, compartmentalized morphology similar to that of photoreceptors in vivo. When treated with the microtubule-depolymerizing agent nocodazole, these elongated photoreceptors became progressively shorter, eventually losing their compartmentalized structure and becoming round. Conversely, treatment with the actin-depolymerizing agent cytochalasin D caused the elongated photoreceptors to lengthen even further. Computer-assisted, quantitative analysis showed that responses of individual cells to both nocodazole and Cytochalasin D were concentration-dependent, graded, and reversible. Immunocytochemical studies suggested the presence of longitudinally oriented actin filaments and microtubules in these photoreceptors, prominent in the region that undergoes the most pronounced length changes in response to cytoskeletal inhibitors. Prior to becoming elongated, photoreceptor precursors could be accurately identified in early retinal cultures. These round cells undergo a stereotyped sequence of morphogenetic transformations during in vitro development, including elongation and compartmentalization of the cell body as well as extension of a single neurite. Treatment with either cytochalasin D or nocodazole completely blocked morphogenetis. In addition, cytochalasin D caused the development of an abnormal, elongated cell process, which formed by a microtubule-dependent mechanism. These nocodazole and cytochalasin D effects also were reversible. Taken together, these data indicate that the complex developmental transformations leading to photoreceptor polarization occur in the absence of intercellular contacts, and are predominantly controlled by intracellular cytoskeletal forces. They suggest the existence of continuously active, oppositely directed, microtubule- and actin-dependent forces, the balance of which is a determining factor in the development as well as the maintenance of the elongated, compartmentalized organization of photoreceptor cells.
Transfer of Full-Length Dmd to the Diaphragm Muscle of Dmdmdx/mdx Mice through Systemic Administration of Plasmid DNA

Mutations in the gene encoding dystrophin, a large cytoskeletal protein in muscle, lead to Duchenne muscular dystrophy (DMD). Affected individuals often die of respiratory failure resulting primarily from diaphragm muscle degeneration. Here we report a new procedure to transfer the full-length dystrophin cDNA into the diaphragm muscle of Dmdmdx/mdx mice, which carry a mutation in the dystrophin gene (Dmd). Significant gene transfer was found after intravenous injection of naked plasmid DNA followed by a brief (eight second) occlusion of blood flow at the vena cava. This is the first demonstration of gene transfer into the diaphragm muscle through systemic administration of naked plasmid DNA. The approach has potential application for treatment of DMD.
Histological investigation of bone induction by demineralized allogeneic bone matrix: A natural biomaterial for osseous reconstruction

The objective of the study was to delineate the histological sequence of events associated with bone formation induced in extraosseous sites by implants of demineralized allogeneic bone matrix (DABM) in order to provide a more complete basis for the clinical use of the natural biomaterial for osseous reconstruction. The rat was the experimental animal model. Implants were prepared by demineralization of diaphyseal cortical rat bone in 0.6N HCl for 18–24 h. A total of 104 specimens, 4 mm square, were implanted both subcutaneously and intramuscularly in 26 rats for periods of 3 days to 22 weeks. Histological evaluation revealed a sequence of events that at 3 days displayed an inflammatory response to surgical trauma and after 6 weeks exhibited the formation of a mature lamellar ossicle with central marrow which was maintained through 22 weeks. Resorption of the DABM, first evident at 1 week, was accompanied by the appearance of chondroblasts in vascular canals and in crevices in the implant. Osteoblastic activity, initially seen at 2 weeks, appeared to be associated with capillary and blood vessel formation around the implant and within enlarged resorptive cavities within the specimens. Calcification occurred in the cartilaginous matrix and osteoid and within the implanted matrix. The osteoinductive process comprises (1) the inflammation / granulation / scar formation processes elicited by implantation of a material, (2) the resorptive response elicited by DABM, and (3) the process of induction of nonosseous mesenchymal cells to differentiate to chondroblasts and osteoblasts. The results of the present study support previous investigations demonstrating the bone-inducing property of DABM and provide further evidence for the potential value of this natural biomaterial for use in osseous reconstruction.
Reactivity of Pt and Pt-Sn alloy surfaces probed by activation of C5-C8 cycloalkanes via electron-induced dissociation (EID) of multilayers

The surface chemistry of cycloalkanes and cycloalkyl intermediates on Pt-Sn alloys is important to the function of selective hydrocarbon conversion catalysts, yet very little is known about this chemistry because cycloalkane decomposition is strongly suppressed under UHV conditions on Pt-Sn alloys and there are few other clean sources of these intermediates. Low-energy, electron-induced dissociation (EID) in multilayers of saturated hydrocarbons produces rather cleanly reactive intermediates formed by the selective cleavage of one C-H bond. This method was used to activate C 5 -C 8 cycloalkane multilayers and prepare monolayer coverages of cycloalkyl species on Pt(111) and two well-defined Pt-Sn alloy surfaces-the p(2 x 2)-Sn/Pt(111) and (√3x √3)R30°Sn/Pt(111) surface alloys formed by vapor deposition of Sn on a Pt(111) substrate. EID of the multilayers and subsequent thermal reactions of the intermediates on these surfaces were investigated by temperature-programmed desorption (TPD), Auger electron spectroscopy (AES), and low-energy electron diffraction (LEED). Adsorbed cycloalkyl species dehydrogenate facilely on both alloy surfaces, but alloying with Sn weakens the bonding to the surface of the cycloalkenes formed and strongly suppresses cycloalkene dehydrogenation. This chemistry leads to a much higher selectivity for the evolution of gas-phase cycloalkenes from the dehydrogenation of cycloalkyl intermediates compared to that on Pt(111).
A hierarchy of campsite attributes in dispersed recreation settings

Abstract Knowledge about preferences for campsite attributes is needed so that management strategies can be guided by users’ preferences for settings and experiences. However, results of campsite choice studies have shown great variability across settings. Reexamination of this research shows a hierarchical typology of attributes: most important are necessity attributes, which supply basic camping needs, followed by experience attributes, which enhance preferred experience outcomes, and finally amenity attributes, which are relatively minor but can improve site quality. A survey of Whitewater boaters confirmed the predicted order of attribute importance and generally supported the proposed definitions of attribute types. A tentative model of campsite choice is offered in which sites are evaluated first for their ability to provide necessity attributes, then experience attributes, and finally, if more than one potential site remains, amenity attributes. Constraints may cut the evaluation process short anyt...
Variability of trace-metal fluxes through the Strait of Gibraltar

Van Geen, A. and Boyle, A., 190. Variability of trace-metal fluxes through the Strait of Gibraltar. In: L.D. Labeyrie and C. Jeandel (Editors), Geochemical Variability in the Oceans, Ice and Sediments. Palaeogeogr., Palaeoclimatol., Palaeoecol. (Global Planet. Change Sect.), 89: 65-79.. Three water masses originating in the Atlantic and entering the Alboran Sea through the Strait of Gibraltar have recently been identified on the basis of salinity and Cu, Ni, Cd and Zn concentrations. The endmembers are (1) Atlantic surface water, (2) North Atlantic Central Water and (3) Spanish shelf water. Spanish shelf water is of particular relevance to the trace-metal composition of the inflow to the Mediterranean Sea because this water mass is highly enriched in Cu, Cd and Zn relative to Atlantic surface water. Here, a conservative mixing model is solved for the above Atlantic endmembers, (with the addition of (4) a Mediterranean deep-water endmember) by weighted least-squares and shown to be consistent with tracer data for 42 surface samples collected in April '86 within the Strait of Gibraltar. Sensitivity of the solution to errors in the data and the assumptions of the model are discussed in detail. Uncertainties in the proportions of metal-enriched Spanish shelf water and NACW are (at most) on the order of 6 and 16%, respectively, and often smaller depending on the composition of a given sample. The inversion shows that Spanish shelf water is present predominantly in the northern half of the Strait and contributes up to 55% to Alboran Sea surface samples. Determining a representative composition of the inflow is complicated, however, by rapid change in the proportion of the three Atlantic endmembers present in the Strait of Gibraltar: entrainment of Spanish shelf water through the Strait roughly doubles between April 11 and 17. We show that the timing of collection of these samples minimizes a potential bias in endmember distributions simply due to variable tidal currents. The increase in entrainment of Spanish shelf water from neap tide to spring tide could, therefore, reflect a significant shift to the north of source waters to the Atlantic inflow over the course of a week. The data show that entrainment of Spanish shelf water is a significant source of the increased Cu, Cd and Zn concentrations observed in the Mediterranean relative to open Atlantic surface water, and this source may even account for the greater part of the Mediterranean enrichments.
The minimum wage and tipped employees

Using data from theCensus of Retail Trade, I estimate that allowing restaurants to use servers’ tipped income to satisfy minimum wage requirements would create at least 360,000 new high-paying jobs and increase total income for tipped workers by at least 8 percent. Conversely, if the minimum wage were increased 10 percent, tipped workers would experience a 4 percent decrease in employment and a 6 percent reduction in hours worked, and all servers (tipped and non-tipped) would experience a 3 to 5 percent decrease in total income because the tipped jobs lost paid more than the minimum wage. By not allowing employers to use all of a worker’s tipped income to meet the minimum wage, state and federal minimum wage laws inhibit the creation of hundreds of thousands of new jobs paying well above the minimum wage. Total elimination of this credit would decrease employment at least 10 percent.
The mTOR inhibitor CCI-779 induces apoptosis and inhibits growth in preclinical models of primary adult human ALL

Acute lymphoblastic leukemia (ALL) in adult patients is often resistant to current therapy, making the development of novel therapeutic agents paramount. We investigated whether mTOR inhibitors (MTIs), a class of signal transduction inhibitors, would be effective in primary human ALL. Lymphoblasts from adult patients with precursor B ALL were cultured on bone marrow stroma and were treated with CCI-779, a second generation MTI. Treated cells showed a dramatic decrease in cell proliferation and an increase in apoptotic cells, compared to untreated cells. We also assessed the effect of CCI-779 in a NOD/SCID xenograft model. We treated a total of 68 mice generated from the same patient samples with CCI-779 after establishment of disease. Animals treated with CCI-779 showed a decrease in peripheral-blood blasts and in splenomegaly. In dramatic contrast, untreated animals continued to show expansion of human ALL. We performed immunoblots to validate the inhibition of the mTOR signaling intermediate phospho-S6 in human ALL, finding down-regulation of this target in xenografted human ALL exposed to CCI-779. We conclude that MTIs can inhibit the growth of adult human ALL and deserve close examination as therapeutic agents against a disease that is often not curable with current therapy.
Non-linear sigma model with CP violation

Abstract Some counterparts of the anomalous Ward identity of QCD in the effective theory proposed here are different from the previous ones and seem akin to the underlying QCD theory.
Transformer 2β homolog (Drosophila) (TRA2B) Regulates Protein Kinase C δI (PKCδI) Splice Variant Expression during 3T3L1 Preadipocyte Cell Cycle

Obesity is characterized by adipocyte hyperplasia and hypertrophy. We previously showed that PKCδ expression is dysregulated in obesity (Carter, G., Apostolatos, A., Patel, R., Mathur, A., Cooper, D., Murr, M., and Patel, N. A. (2013) ISRN Obes. 2013, 161345). Using 3T3L1 preadipocytes, we studied adipogenesis in vitro and showed that expression of PKCδ splice variants, PKCδI and PKCδII, have different expression patterns during adipogenesis (Patel, R., Apostolatos, A., Carter, G., Ajmo, J., Gali, M., Cooper, D. R., You, M., Bisht, K. S., and Patel, N. A. (2013) J. Biol. Chem. 288, 26834–26846). Here, we evaluated the role of PKCδI splice variant during adipogenesis. Our results indicate that PKCδI expression level is high in preadipocytes and decreasing PKCδI accelerated terminal differentiation. Our results indicate that PKCδI is required for mitotic clonal expansion of preadipocytes. We next evaluated the splice factor regulating the expression of PKCδI during 3T3L1 adipogenesis. Our results show TRA2B increased PKCδI expression. To investigate the molecular mechanism, we cloned a heterologous splicing PKCδ minigene and showed that inclusion of PKCδ exon 9 is increased by TRA2B. Using mutagenesis and a RNA-immunoprecipitation assay, we evaluated the binding of Tra2β on PKCδI exon 9 and show that its association is required for PKCδI splicing. These results provide a better understanding of the role of PKCδI in adipogenesis. Determination of this molecular mechanism of alternative splicing presents a novel therapeutic target in the management of obesity and its co-morbidities.
Cytokines regulate gelatinase A and B (matrix metalloproteinase 2 and 9) activity in cultured rat astrocytes

: Under a tightly regulated expression mechanism, matrix metalloproteinases degrade extracellular matrix proteins and are though to play a role in injury repair and tumor metastasis in peripheral tissues. Little is known about the function of matrix metalloproteinases or agents that regulate their production in adult brain; however, it has been shown that the activity of a calcium-dependent metalloproteinase is elevated in Alzheimer's hippocampus. The goals of this study were to determine whether cultured rat astrocytes produce matrix metalloproteinases and to identify agents that regulate protease activity. Enriched astrocyte cultures were prepared from brains of 1-day-old rat pups, and experiments were performed 13 days later. Gelatinase activity in astrocyte conditioned medium was determined using zymography with gelatin copolymerized with acrylamide in the gel. Under basal conditions after a 24-h incubation, rat astrocytes produce gelatinases of 58 and 66 kDa. On stimulation of astrocytes with lipopolysaccharide, interleukin-1α or -β, or tumor necrosis factor-α for 24 h, a dose-dependent increase in the activity of the 58- and 66-kDa gelatinases and the induction of a 94-kDa gelatinase occurred. All three astrocyte-derived proteases showed maximal activity in the presence of millimolar levels of Ca2+, their activity was inhibited in the presence of 1,10-phenanthroline, and their proenzymes were cleaved and activated after incubation with p-aminophenylmercuric acetate. Using immunoblotting, immunopositive bands at the respective molecular sizes indicated that the 58-kDa gelatinase was gelatinase A (matrix metalloproteinase 2) and the 94-kDa activity was gelatinase B (matrix metalloproteinase 9). Induction of the 94-kDa gelatinase by lipopolysaccharide was not influenced when interleukin-1 receptor antagonist was included during the 24-h incubation period; however, the antagonist completely blocked interleukin-1β-induced 94-kDa activity and diminished the activity of the 58- and 66-kDa gelatinases. Dexamethasone inhibited both lipopolysaccharide and interleukin-1β stimulation of the 94-kDa gelatinase. These results indicate that cytokines regulate matrix metalloproteinase expression in cultured rat astrocytes. Because astrocytes become “activated” (are hypertrophic and express increased levels of glial fibrillary acidic protein) in the presence of several inflammatory cytokines, it is possible that these astrocyte-derived enzymes contribute to the activation process and may participate in tissue remodeling after brain injury.
Undue inducements and reasonable risks: will the dismal science lead to dismal research ethics?

The concept of risk plays a prominent role in research ethics and though great pains are often taken to define “risk” as the product of the magnitude of a harm and the probability that it will occu...
Regulation of sexual differentiation in D. melanogaster via alternative splicing of RNA from the transformer gene

The transformer (tra) gene regulates female somatic sexual differentiation and has no known function in males. It gives rise to two sizes of RNA, one non-sex-specific and one female-specific. These two RNAs are shown to be present throughout the life cycle, and related by the use of alternative first intron splice acceptor sites. The non-sex-specific RNA has a 73 base first intron, while that in the female-specific RNA is 248 bases. The non-sex-specific RNA has no long open reading frame, while the female-specific RNA has a single long open reading frame beginning at the first AUG. Substitution of a heat shock promoter for the tra promoter still leads to female-specific differentiation of otherwise tra-females. We suggest a mechanism by which Sex-lethal controls itself and tra.
Transthyretin Interacts with Amyloid-β Oligomers to Delay Amyloid Aggregation

Protective effects of Transthyretin (TTR) ameliorate Alzheimer's pathology in mice models. This suggests a possible route for cellular defense mechanism against toxic effects of protein misfolding and aggregation. This view is further supported by the results from in vitro experiments showing direct interactions between TTR and amyloid-β (Aβ) peptides. However, the molecular mechanism of the TTR-Aβ interactions is currently unknown primarily due to heterogeneities associated with self-association of both TTR and Aβ. Here we investigate the mechanism of TTR-Aβ interactions by examining the effects of WT-human, a monomeric mutant and murine TTR on the kinetics of aggregation of both Aβ1-40 and Aβ1-42. The three of forms of TTR differ in terms of stability as tetramers or monomers, e.g., the WT-human and murine TTR are primarily tetramers but the tetramers of murine TTR are more stable. To monitor the aggregation of Aβ but not of TTR we use a recently developed aggregation assay based on the fluorescence quenching of tetramethyl rhodamine (TMR)-labeled Aβ. Our data indicate that all three TTR variants delay aggregation of both Aβ1-40 and Aβ1-42. However, the effects are strongest for the monomeric mutant and weakest for the murine TTR. Kinetic measurements of fluorescence resonance energy transfer between native tryptophan residues of TTR and the EDANS-labeled Aβ indicate that binding of TTR is dependent on the aggregation status of Aβ with maximal binding occurring to larger aggregates of Aβ. Additionally, the modulatory effects of TTR are stronger on Aβ1-42 than on Aβ1-40 consistent with the known higher oligomerization propensity for Aβ1-42. Taken together our results indicate that the tetramers of WT-human TTR dissociates to monomers to bind to the aggregation intermediates of Aβ to subsequently slow down the growth of these intermediates.
OBSERVATIONS ON THE MECHANISM OF ACTION OF ESTROGENS AT THE CELLULAR LEVEL

Evidence from many types of experiments leads to the conclusion that the prime effect of estrogens in the intact animal is the dif? ferential growth of certain tissues, the socalled target organs. Growth itself is a symphony of energy-requiring processes, involving the synthesis of nucleic acids, proteins, lipids, and other substances. In a particular tissue at a given moment, growth could be occurring at something less than the maximal rate if one of the substrates for protein, nucleic acid or lipid synthesis were present in lower than optimal concentrations, or if the activity of at least one enzyme in each of these biosynthetic pathways was depressed. A hormone then could stimulate growth in the tissue by increasing either the amount or the activity of one enzyme or a group of enzymes, or by increasing the amount of some substrate or cofactor, or by decreasing the concentration of an inhibitor or a repressor. When estrogen is administered to an in? tact animal, only some of its tissues, not all, respond with an increased rate of growth. The question of what distinguishes these responsive tissues from the unresponsive or the relatively less responsive tissues of the animal is part of the general problem of the biochemical basis of cell differentiation. According to current theories, each nu? cleus in a multicellular organism has the same genetic complement as every other nu? cleus, and contains the entire set of genetic information that every other cell has. The DNA in the nucleus is believed to mediate
Trauma experience comparison of army forward surgical team surgeons at Ben Taub Hospital and Madigan Army Medical Center

Far forward life-saving surgical care is the mission of an army forward surgical team (FST). Trauma skill maintenance is necessary to complete that mission. A new program has been developed for FST training using the resources of a Level 1 trauma center. We sought to compare the experience of FST surgeons at a major urban trauma center with the yearly trauma experience at an army Level 2 trauma center.General surgeons of the 250th FST prospectively tabulated data for trauma patients during a September 1999 unit deployment to Ben Taub Hospital (Houston, Texas). Data collected included nature and location of injury, hospital admission, and surgical intervention. During 1999, similar data were collected at Madigan Army Medical Center (MAMC) (Ft. Lewis, Washington), home station of the 250th and Level 2 trauma center since November 1998.The FST general surgeons observed 319 injuries. Of those injured, 104 were admitted and 19 underwent urgent operation. Direct participation by FST general surgeons in the operative procedures varied. In 1999, MAMC general surgeons treated 455 trauma victims in direct supervision of Army general surgery residents. Madigan Army Medical Center general surgeons admitted 304 and urgently operated on 57 trauma patients, while 107 patients were transferred to another institution for definitive management of orthopedic and nonoperative neurosurgical injuries.CONCLUSIONS:The volume of trauma surgical cases at MAMC during 1999 was 3 times that seen in the 1-month rotation at Ben Taub. General surgeons performed more trauma and abdominal surgery at MAMC with significantly more direct involvement in patient care and operative procedures. The experience of the 250th FST does not justify trauma sustainment deployments for surgeons from military trauma centers.
Unilateral headache and ptosis in a 30-year-old woman

A 30-year-old woman developed left-sided headaches and ipsilateral oculosympathetic paresis (Horner's syndrome) secondary to carotid dissection. Although she initially denied preceding trauma, further questioning revealed a pattern of physical abuse by her boyfriend, including an attempted strangulation shortly before onset of symptoms. This case highlights the need for increased awareness of domestic violence among health care providers.
How Do Commercial Institutions Promote Peace

commitment problems in international bargaining. The statistical results show empirical support for only the third explanation. Commercial institutions with more organs for high-level state leaders demonstrate a substantively strong and statistically significant effect in reducing the outbreak of military conflict. But commercial institutions with deeper economic integration and nested military-security structures are not associated with less military conflict. Together, these results suggest that the observed commercial institutional peace does not stem from economic integration per se, but rather from certain institutional structures that often accompany the regional integration process. Thus, the commercial institutional peace appears more related to the third leg of the Kantian tripod (international organizations) than to the second leg (international commerce).
Correctness proof for the majority consensus algorithm

Abstract We give a formal proof of correctness of the Thomas majority consensus algorithm using temporal logic.
Investigation on Lippmann photographs: materials, processes, and color rendition

Reality of holographic image can be effectively improved by multicolor reconstruction. This fact is applicable to real-time 3D display by computer generated hologram (CGH). However, generating CGH for multicolor imaging in real-time is quite difficult because a CGH contains huge amount of information and it is multiplexed by the number of primary colors for multicolor imaging. Moreover, an optical system for multicolor reconstruction tends to be rather complicated. This paper presents a new method to reconstruct 3D multicolor images from CGH. In this method, three sub-holograms reconstructing primary color images are sampled respectively to reduce the amount of computation and realize the simple optical system. Fringe patterns are displayed on only one spatial light modulator and color crosstalk images are eliminated with color filtering system to ensure that each sub-hologram is illuminated only with the light of the appropriate color. As the experimental results, multicolor images from CGH using this method and the improvement of calculation time to generated multicolor images are shown.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Quality assurance of treatment plans for interstitial and intracavitary high-dose-rate brachytherapy

PURPOSE: Quality assurance for complex high-dose-rate (HDR) treatment planning has always been a challenge to the physics community because of the time constraint between HDR planning and the delivery of the treatment. This study proposes an efficient, precise, and easy method for checking the complex computer calculation. METHODS AND MATERIALS: Posttreatment, three-dimensional dose-volume study was per- formed for 98 patients with 128 new treatment plans along with 30 library plans. Volumes covered by the 100% isodose line, source activity (Ci), total dwell time (s), and the prescription dose (100%) were recorded. Variation of RV defined as (irradiated timeactivity/elongation factorprescribed dose) with volume was studied for different catheter systems. RESULTS: Parametric fit of RV with volume for three different systems that cover most of the in- terstitial and intracavitary brachytherapy implants agrees within G6%. CONCLUSIONS: The excellent agreement of RV derived from this simplistic point source model with three-dimensional dose calculations for individual HDR treatment plans clearly establishes that for an implant with known number of catheters, the time needed to deliver a prescribed dose to a given prescription volume can be easily predicted. 2006 American Brachytherapy Society. All rights reserved.
Takayasu’s arteritis: Operative results and influence of disease activity

Objectives To determine the short- and long-term outcomes of patients treated operatively for Takayasu's arteritis and the effect of disease activity on results. Methods Forty-two (17%) of the 251 patients enrolled in our Takayasu's arteritis registry between 1975 and 2002 required operation for symptomatic disease. Data were obtained from the registry, patient records, phone correspondence, and written surveys. Results There were 38 females and 4 males with a median age of 29 years (range, 12 to 56 years), and 32 (76%) were white. Sixty operations were performed for symptomatic disease. The mean duration of symptoms before operation was 5.6 months (range, 0 to 25 months). Thirteen (31%) patients had active disease and underwent operation for acute presentation or failure of medical management. Thirty-nine patients (93%) had operation for occlusive disease. Twenty-two (52%) patients had involvement of both the great and abdominal aortic branch vessels; 10 (24%) had great vessel disease alone; 9 (21%) had involvement of abdominal arteries; and 1 (2%) had coronary artery disease. There was no operative death, myocardial infarction, major stroke, or renal failure. Three patients had early graft thrombosis, two had a minor stroke, and two developed hyperperfusion syndrome. The median follow-up was 6.7 years (range, 1 month to 19.3 years). Eleven (26%) patients required 15 graft revisions; five of the patients had active disease at the time of initial operation. All early revisions ( Conclusions The minority of patients with Takayasu's arteritis require operation. In our predominantly white female patient population, occlusive symptoms were the most common indication for operation. Operation for these selected patients was safe, with no operative mortality, myocardial infarction, major stroke, or renal failure. Patients with active disease requiring operation are more likely to require revision or develop progressive symptomatic disease at another site. Long-term survival is excellent, regardless of disease activity at the time of operation.
HYDROGEN-MINERAL REACTIONS AND THEIR APPLICATION TO THE REMOVAL OF IRON FROM SPODUMENE

Pegmatitic deposits contain three distinctly different types of spodumene: 1. (1) Phenocrystic spodumene in unzoned pegmatites. This type is high-iron spodumene, with Fe2O3 = 0.6 − 0.9%. 2. (2) Zonal spodumene. Large laths in central zones; it contains 0.01–0.03% Fe2O3. 3. (3) Spodumene plus quartz aggregates pseudomorphous after petalite; Fe2O3 = 0.007 − 0.03%. Only Type 1 generally occurs in deposits sufficiently large and uniform to be economically exploitable. Two processes are presently available for iron removal. Both require initial inversion of the (a) spodumene to its β-dimorph: 1. (1) The chlorine process in which the isomorphous iron is converted to bon chloride and 2. (2) The hydrogen process in which the Fe3+ ion is reduced to metallic iron. Hydrogen-mineral reactions, such as hydrogen-carbonate reactions, are potential sources of lime, methane and iron. They also are important for the benefication of such ceramic materials as spodumene and feldspar.
Is There a Molecular Logic That Sustains Neuronal Functional Integrity and Survival? Lipid Signaling Is Necessary for Neuroprotective Neuronal Transcriptional Programs

A challenge to civilization is the growing incidence in the loss of sight and cognition due to increased life expectancy. Therefore, we are confronted with a rise in the occurrence of photoreceptor- and neuronal-survival failure, as reflected mainly by age-related macular degeneration (AMD) and Alzheimer’s disease (AD). Nervous system development is driven by neuronal apoptotic cell death, and thereafter, for the entire lifespan of an organism, neurons are postmitotic cells. In neurodegenerative diseases, apoptosis and other forms of cells death lead to selective neuronal loss. Although age is the main risk factor, not everyone develops these diseases during aging. Despite decades of important findings about neuronal cell death, the specific mechanisms that regulate neuronal survival remain incompletely understood.
Expression, purification, and PC1-mediated processing of human proglucagon, glicentin, and major proglucagon fragment

Abstract To examine the cleavage specificity of different members of the furin/propeptide convertase (PC) family of enzymes, we have selected proglucagon (PG) as a model substrate. PG was selected because it is subject to differential processing in vivo. PG is thought to be cleaved initially at an interdomain site to produce glicentin and the major proglucagon fragment (MPGF). These intermediates are subsequently cleaved, most likely by the convertases PC2 and PC1, respectively. To determine the exact sites within PG that are cleaved by PC1 and PC2, we attempted to produce milligram quantities of human PG, glicentin, and MPGF for use in an in vitro conversion assay. A methionine residue was added to the N-terminus of each protein to initiate translation. Purification was achieved using cation exchange and reversed-phase chromatography, and the integrity of the methionylated proteins was confirmed by both electrospray ionization-mass spectrometry and amino acid analysis. The combined expression and purification scheme is fast, efficient, and results in milligram quantities of ⩾95% pure proglucagon, ⩾95% pure MPGF, and ⩾93% pure glicentin. These prohormones are cleaved by PC1 to produce product peptides consistent with the processing of PG observed in vivo, and should therefore be suitable for further analysis of the post-translational processing of PG.