cssi/SciSciGPT-SciSciNet huggingface dataset:
Cardiovascular Risk and Resilience Among Black Adults: Rationale and Design of the MECA Study

Background Cardiovascular disease incidence, prevalence, morbidity, and mortality have declined in the past several decades; however, disparities persist among subsets of the population. Notably, blacks have not experienced the same improvements on the whole as whites. Furthermore, frequent reports of relatively poorer health statistics among the black population have led to a broad assumption that black race reliably predicts relatively poorer health outcomes. However, substantial intraethnic and intraracial heterogeneity exists; moreover, individuals with similar risk factors and environmental exposures are often known to experience vastly different cardiovascular health outcomes. Thus, some individuals have good outcomes even in the presence of cardiovascular risk factors, a concept known as resilience. Methods and Results The MECA (Morehouse-Emory Center for Health Equity) Study was designed to investigate the multilevel exposures that contribute to "resilience" in the face of risk for poor cardiovascular health among blacks in the greater Atlanta, GA, metropolitan area. We used census tract data to determine "at-risk" and "resilient" neighborhoods with high or low prevalence of cardiovascular morbidity and mortality, based on cardiovascular death, hospitalization, and emergency department visits for blacks. More than 1400 individuals from these census tracts assented to demographic, health, and psychosocial questionnaires administered through telephone surveys. Afterwards, ≈500 individuals were recruited to enroll in a clinical study, where risk biomarkers, such as oxidative stress, and inflammatory markers, endothelial progenitor cells, metabolomic and microRNA profiles, and subclinical vascular dysfunction were measured. In addition, comprehensive behavioral questionnaires were collected and ideal cardiovascular health metrics were assessed using the American Heart Association's Life Simple 7 measure. Last, 150 individuals with low Life Simple 7 were recruited and randomized to a behavioral mobile health (eHealth) plus health coach or eHealth only intervention and followed up for improvement. Conclusions The MECA Study is investigating socioenvironmental and individual behavioral measures that promote resilience to cardiovascular disease in blacks by assessing biological, functional, and molecular mechanisms. REGISTRATION URL: https://www.clini​caltr​ials.gov. Unique identifier: NCT03308812.
Does the neighbourhood matter for neighbourhood satisfaction? A meta-analysis:

Urbanists are keenly interested in individuals’ satisfaction with their neighbourhoods, and especially in the determinants of satisfaction. To the extent that we all want to be satisfied with our n...
Through-thickness regional variation in the mechanical characteristics of the lumbar facet capsular ligament

The human lumbar facet capsule, with the facet capsular ligament (FCL) that forms its primary constituent, is a common source of lower back pain. Prior studies on the FCL were limited to in-plane tissue behavior, but due to the presence of two distinct yet mechanically different regions, a novel out-of-plane study was conducted to further characterize the roles of the collagen and elastin regions. An experimental technique, called stretch-and-bend, was developed to study the tension-compression asymmetry of the FCL due to varying collagen fiber density throughout the thickness of the tissue. Each healthy excised cadaveric FCL sample was tested in four conditions depending on primary collagen fiber alignment and regional loading. Our results indicate that the FCL is stiffest when the collagen fibers (1) are aligned in the direction of loading, (2) are in tension, and (3) are stretched − 16% from its off-the-bone, undeformed state. An optimization routine was used to fit a four-parameter anisotropic, hyperplastic model to the experimental data. The average elastin modulus, E, and the average collagen fiber modulus, ξ, were 13.15 ± 3.59 kPa and 18.68 ± 13.71 MPa (95% CI), respectively.
Does Wall Street Understand Fed Speak? Monetary Policy Communication and Corporate Conference Calls

We uncover a tone transmission channel of monetary policy wherein the linguistic tone of press releases by the Fed shapes the linguistic tone of macro-related dialogues in corporate conference calls occurring days after such releases. Applying machine-learning techniques to a granular dataset of dialogues between managers and equity analysts during conference calls, we find that the tone of macro-related dialogues is reflected in both contemporaneous stock market reactions as well as subsequent equity analysts' stock recommendations. Critically, the semantic content of monetary policy releases is consistently observed in macro dialogues between managers and analysts. A large sample analysis suggests that the effect of monetary policy tone on corporate conference calls is stronger in more recent years and for major unconventional monetary policy announcements. Taken together, our results shed light on how economic agents interpret "Fed Speak,'' underscoring non-transitory effects of monetary policy communication.
Reliability Evaluation of PhotoVoltaic and Energy Storage Integrated Systems with Frequency Security Constraint

The increasing integration of solar power into the grid impacts the system reliability and stability due to its generation intermittency and low inertia. One of the major problems with increasing photovoltaic power integration is the reduction in system frequency stability as low inertia photovoltaic systems become more competitive with conventional generators in economic and environmental sectors. In this paper, a frequency security constraint based dynamic integration limit assessment technique is presented for solar power integrated system. This assessment technique will limit the integration of photovoltaic power based on system inertia while considering system status changes. Based on the dynamic integration limit assessment, a coordinated strategy for the energy storage system is formulated in order to improve the system reliability. The energy storage system is designed to maximize the renewable energy utilization in the system, smooth the photovoltaic power output and minimize system outage while considering the system frequency stability. The effectiveness of the proposed method is demonstrated using the modified IEEE RTS-79 system.
A variable gain high linearity low power baseband filter for WLAN

This paper presents a 4/sup th/ order low-pass baseband filter for WLAN applications, implemented in a 1.5V 3V 0.15/spl mu/m CMOS process. The active-RC configuration uses single amplifier biquads (SABs) to save power and has resistor and capacitor arrays to provide variable gain and bandwidth trimming. The biquads are implemented using three-stage opamps and a hybrid /spl pi/-to-tee transformation network for the resistor arrays, so that higher linearity than conventional Sallen-Key circuits may be obtained. The filter achieves a measured THD of -72 dB at 1 MHz.
Threonine Deaminase of Clostridium tetanomorphum II. DISSOCIATION TO SUBUNITS

Abstract Dissociation of the threonine deaminase of Clostridium tetanomorphum occurs upon exposure to heat, to alkaline pH, or to denaturing agents, or when preparations are diluted or allowed to age at -20°. Dissociation in the presence of urea, detergents, or an alkaline pH may be prevented by addition of adenosine diphosphate, threonine, phosphate buffer at pH 7.0, or monovalent or divalent cations. Association of isolated lower molecular weight materials, obtained in partially purified form by gel filtration, is promoted by ADP and threonine. The ability to be aggregated by ADP may be lost by prolonged exposure to dissociating agents. ADP is more efficient than threonine in preventing dissociation or promoting association. At least eight molecular species, detected by a sucrose gradient centrifugation and gel filtration, have been derived from purified preparations of the enzyme. Seven of these are enzymatically active; the smallest forms, produced by alkylation following treatment with urea and β-mercaptoethanol, are enzymatically inactive. The kinetic properties and heat stability of the fully polymerized enzyme and three of the dissociated forms have been compared.
Resistance to neutralization by broadly reactive antibodies to the human immunodeficiency virus type 1 gp120 glycoprotein conferred by a gp41 amino acid change.

A neutralization-resistant variant of human immunodeficiency virus type 1 (HIV-1) that emerged during in vitro propagation of the virus in the presence of neutralizing serum from an infected individual has been described. A threonine-for-alanine substitution at position 582 in the gp41 transmembrane envelope glycoprotein of the variant virus was responsible for the neutralization-resistant phenotype (M.S. Reitz, Jr., C. Wilson, C. Naugle, R. C. Gallo, and M. Robert-Guroff, Cell 54:57-63, 1988). The mutant virus also exhibited reduced sensitivity to neutralization by 30% of HIV-1-positive sera that neutralized the parental virus, suggesting that a significant fraction of the neutralizing activity within these sera can be affected by the amino acid change in gp41 (C. Wilson, M. S. Reitz, Jr., K. Aldrich, P. J. Klasse, J. Blomberg, R. C. Gallo, and M. Robert-Guroff, J. Virol. 64:3240-3248, 1990). It is shown here that the change of alanine 582 to threonine specifically confers resistance to neutralizing by antibodies directed against both groups of discontinuous, conserved epitopes related to the CD4 binding site on the gp120 exterior envelope glycoprotein. Only minor differences in binding of these antibodies to wild-type and mutant envelope glycoproteins were observed. Thus, the antigenic structure of gp120 can be subtly affected by an amino acid change in gp41, with important consequences for sensitivity to neutralization. Images
Abstract T P223: Post-stroke Body Weight Loss Predicts Acute Stroke Outcome In Mice

Background and Purpose: Longitudinal imaging studies in stroke demonstrated that infarct development is a dynamic process and it matures over several days, even weeks depending on the severity of stroke. However, due to high cost and multiple exposure of anesthesia associated with repeated imaging, infarct volume has been typically measured at a fixed time point in preclinical studies, which prevent further assessment of behaviors during stroke recovery. In identifying a non-invasive physiological parameter that predicts the extent of stroke-induced brain injury, the study investigated whether acute body weight loss predicts the extent of brain injury and swelling. Methods: C57 male mice (10-12 wk old, 25-30 gr) were subjected to the proximal middle cerebral artery (MCA) occlusion for 30 min. Body weight was recorded daily. Infarct volume corrected with swelling (IVInd) and percent hemispheric swelling (%SW) were determined at 1, 3 and 7d after MCAO. In a retrospective study, we analyzed correlations between 3d %body weight reduction (%BWred) and stroke outcomes (IVInd & %SW) in C57 male animals that were subjected to MCAO by 3 different individuals over 8 years (n=91-96). Results: Stroke induced acute BW loss (%BWred; 1d, 88.9±3.3; 3d, 84.5±8.6; 5d, 86.8±10.6; 7d, 88.9±8.9). Correlation analyses in the post-ischemic time points showed IVind and %SW were significantly correlated with only at 3d BW reduction, but not 1d and 7d (Fig.1). A retrospective analysis in C57 mice also showed a significant correlation between 3d %BWred and IVInd & %SW (Fig.2). Conclusions: The study showed that acute post-stroke BWred is a simple and suitable index to predict the extent of stroke injury in C57 mice. Whether the prediction can be generalized across different strains and in comorbid conditions warrant further investigation. ![][1] [1]: /embed/graphic-1.gif
Controller Design for Uncertain Systems via Lyapunov Functions

We present a controller design methodology for uncertain systems which is based on the constructive use of Lyapunov functions. The uncertainties, which are deterministic, are characterized by certain structural conditions and known bounds. As a consequence of the Lyapunov approach, the methodology is not restricted to linear systems. The robustness of these controllers in the presence of singular perturbations is considered. The situation in which the full state of the system is not available for measurement is also considered. These controllers are illustrated by application to the tracking control of a Manutec r3 robot which has an uncertain payload.
Analysis of pulse coherence property of actively mode-locked inhomogeneously broadened lasers using space-time analogy

Inhomogeneously broadened lasers have weak spectral narrowing and can generate potentially ultrashort laser pulses. However, the coherence of the actively mode-locked pulses depends on the modulation strength and often is not guaranteed. In this paper an analysis of the pulse coherence property of actively mode-locked inhomogeneously broadened lasers using the space-time analogy in optics is presented. The analytic formulation determines the coherence property of the actively mode-locked laser pulses, and theoretical calculations are in agreement with experimental observations.
Graph-Based Robust Resource Allocation for Cognitive Radio Networks

Cognitive radio (CR) technology is promising for next generation wireless networks. It allows unlicensed secondary users to use the licensed spectrum bands as long as they do not cause unacceptable interference to the primary users who own those bands. To efficiently allocate resources in CR networks, stable resource allocation based on graph theory is investigated, which takes all users' preferences into account. In this paper, we focus on improving robustness of the stable matching based resource allocation. A truncated scheme generating almost stable matchings is first investigated. Based on the properties of the truncated scheme, two types of edge-cutting algorithms, called direct edge-cutting (DEC) and Gale-Shapley based edge-cutting (GSEC), are developed to improve resource allocation robustness to the channel state information variation. To mitigate the problem that certain secondary users may not be able to find suitable resources after edge-cutting, multi-stage (MS) algorithms are then proposed. Numerical results show that the proposed algorithms are robust to the channel state information variation.
Fatty Acids of Myxococcus xanthus

Fatty acids were extracted from saponified vegetative cells and myxospores of Myxococcus xanthus and examined as the methyl esters by gas-liquid chromatography. The acids consisted mainly of C14 to C17 species. Branched acids predominated, and iso-pentadecanoic acid constituted half or more of the mixture. The other leading component (11–28%) was found to be 11-n-hexadecenoic acid. Among the unsaturated acids were two diunsaturated ones, an n-hexadecadienoic acid and an iso-heptadecadienoic acid. No significant differences between the fatty acid compositions of the vegetative cells and myxospores could be detected. The fatty acid composition of M. xanthus was found to be markedly similar to that of Stigmatella aurantiaca. It is suggested that a fatty acid pattern consisting of a large proportion of iso-branched C15 and C17 acids and a substantial amount of an n-16:1 acid is characteristic of myxobacteria.
Optimizing Caching DSM for Distributed Software Speculation

Clusters with caching DSMs deliver programmability and performance by supporting shared-memory programming and tolerate remote I/O latencies via caching. The input to a data parallel program is partitioned across the cluster while the DSM transparently fetches and caches remote data as needed. Irregular applications, however, are challenging to parallelize because the input related data dependences that manifest at runtime require use of speculation for correct parallel execution. By speculating that there are no input related cross iteration dependences, private copies of the input can be processed by parallelizing the loop, the absence of dependences is validated before committing the computed results. We show that while caching helps tolerate long communication latencies in irregular data-parallel applications, using a cached values in a computation can lead to misspeculation and thus aggressive caching can degrade performance due to increased misspeculation rate. We present optimizations for distributed speculation on caching based DSMs that decrease the cost of misspeculation check and speed up the re-execution of misspeculated recomputations. Optimized distributed speculation achieves speedups of 2.24x for coloring, 1.71x for connected components, 1.88x for community detection, 1.32x for shortest path, and 1.74x for pagerank over unoptimized speculation.
Investigation of High Performance Heat Sink Characteristics in Forced Convection Cooling of Power Electronic Systems

This study presents the experimental performance of a high fin density heat sink for semiconductor power modules — such as IGBTs. As a case study a commercially available extruded heat sink has been chosen. By analyzing the steady-state maximum temperatures as well as various geometric orientations, Nusselt number correlations were found experimentally, which can be used to predict the performance of the heat sink. It was found that the experimental Nusselt number correlations can predict the performance of the heat sink to within a 10%. Furthermore, steady-state maximum temperature results showed that for low fan speeds (2 m/s–3 m/s), the device junction temperatures achieved a value no higher than 80°C, which is well below the junction temperature limit for 125°C for silicon power semiconductor devices. Furthermore, it was shown that for two heat sinks in series forced convection tests, gap spacing between the devices has a minimal effect on the overall performance. Also, a numerical simulation study using COMSOL Multiphysics simulation software to study flow and temperature fields has been conducted. These modeling results the thermal behavior of heat sink are validated by experimental measurements.Copyright © 2011 by ASME
Imaging of neuroendocrine tumors: accuracy of helical CT versus SRS

Background: We retrospectively compared the accuracy of somatostatin receptor scintigraphy (SRS) with that of helical computed tomography (CT) in the detection and localization of primary and metastatic neuroendocrine tumors. Methods: A medical record search identified 27 patients with known or clinically suspected neuroendocrine tumors who underwent helical CT and SRS within 3 months of one another at our institution. CT images were evaluated retrospectively by two blinded radiologists who used consensus reading. Images were evaluated for the presence or absence of primary tumor and hepatic and extrahepatic metastases. CT results were compared with the SRS report as interpreted by the nuclear medicine physicians. The results of the surgical, clinical follow-up, and pathologic findings were considered as the gold standard. Sensitivity, specificity, and accuracy were calculated for both imaging techniques. In addition, McNemar analysis was performed to determine statistically significant differences between CT and SRS. Results: Helical CT was more sensitive than SRS in the detection of extrahepatic metastases, and the difference between the two imaging modalities was statistically significant (p = 0.0312) as determined by the McNemar chi-square test. However, the difference between CT and SRS in detecting primary neuroendocrine tumors, hepatic metastasis, and combined hepatic and extrahepatic metastasis was not statistically significant (p = 0.625, 1.000, and 1.000, respectively). Conclusion: Helical CT and SRS have similar sensitivity, specificity, and accuracy in detecting primary neuroendocrine tumor and hepatic metastasis. However, helical CT appears to be more sensitive in detecting extrahepatic metastasis from primary neuroendocrine tumors.
The Dynamics of Party Identification

This article presents a model of individuals' party identification that contrasts with previous models. Past models, with the few recent exceptions noted, assume a hierarchical relationship either from identification to other aspects of political behavior, such as the perception and evaluation of issues and candidates, or from these behaviors to party identifications. The model discussed here places party within a dynamic concept of the electoral process and tests several hypotheses about factors producing changes in identifications. The first factor, consistent with the spatial-type issue voting models, estimates the effects of the relative proximity of each party to the individual's own policy preferences. Second, we examine the effect of the actual voting decision on subsequent identifications, with the expectation that if votes differ from previous identifications, there is a resulting shift in partisanship. Finally, we examine the hypothesis that identifications become less susceptible to change as people age and accumulate political experience. When combined with other research, the results indicate a model of the electoral process in which party identifications are both influenced by circumstances specific to each election and influence other behaviors. This nonrecursive model has a number of implications for the development and evolution of individual and aggregate partisanship. These implications are discussed at the end of the article.
A Coordination Chemist's View of Surface Science

Structure, a necessary element for an understanding of chemistry, has not been precisely defined, in molecular detail, for the surface species formed at a solid-gas interface. Dramatic advances in theory, instruments and experimental procedures have now provided the surface scientists with an impressive arsenal of structural and electronic probes. Chemistry in the form of the classic displacement reaction can also provide an insight to the structure of surface compounds. In fact, many of the experimental procedures and systematics of the coordination and organometallic chemist can be effectively utilized in a complementary fashion with surface physics techniques to gain a more definitive picture of chemisorption states and or reactions at a surface.
A π-Helix Switch Selective for Porphyrin Deprotonation and Product Release in Human Ferrochelatase

Ferrochelatase (protoheme ferrolyase, E.C. 4.99.1.1) is the terminal enzyme in heme biosynthesis and catalyzes the insertion of ferrous iron into protoporphyrin IX to form protoheme IX (heme). Due to the many critical roles of heme, synthesis of heme is required by the vast majority of organisms. Despite significant investigation of both the microbial and eucaryotic enzyme, details of metal chelation remain unidentified. In this work we present the first structure of the wild-type human enzyme, a lead-inhibited intermediate of the wild-type enzyme with bound metallated porphyrin macrocycle, the product bound form of the enzyme, and a higher resolution model for the substrate-bound form of the E343K variant. These data paint a picture of an enzyme that undergoes significant changes in secondary structure during the catalytic cycle. The role that these structural alterations play in overall catalysis and potential protein-protein interactions with other proteins, as well as the possible molecular basis for these changes, is discussed. The atomic details and structural rearrangements presented herein significantly advance our understanding of the substrate binding mode of ferrochelatase and reveal new conformational changes in a structurally conserved π helix that is predicted to have a central role in product release.
Qualitative analysis of radiating breathers

Perturbed sine-Gordon equations are investigated numerically to see if they have breather solutions. It is shown that breathers radiate, blow up, and split into kink-antikink pairs under most perturbations. The two perturbations proven by Birnir, McKean, and Weinstein not to produce radiation, of the first order in the perturbation parameter, a sin(u) + b ucos(u) and 1+3cos(u) - 4cos(u/2) + 4cos(u)log(cos(u/4)), stop radiating first-order radiation after adjusting the initial breather by the emission of such radiation. The first perturbation is a scaling of the breather, the second is shown to give a quasi-periodic orbit, which is a two-breather, on a torus. © 1994 John Wiley & Sons, Inc.
An Experimental Study of the Formation of Perfluoroisobutene

Abstract This paper presents an experimental study that focuses on the formation of perfluoroisobutene (i-C4Fg). Experiments were carried out at atmospheric pressure in a quartz flow tube reactor over the temperature range of 823 to 1273K and an initial reactant feed concentration of 2% with the balance nitrogen. Reactants studied include chlorodifluoromethane (CHF2Cl), 1,1,1,2-tetrafluoro-2-chloroethane (CF3CHFCl), trifluoromethane (CHF3), perfluoropropene (C3F6), and mixtures of these species. Effluent gas concentrations were obtained using a water cooled gas sampling probe, and analysis of products was performed via on line gas chromatography with flame ionization detection and gas chromatography with mass selective detection. C3F6 pyrolysis produced more than 22% i-C.F, yield, while mixtures with CHF2Cl and CHF3 resulted in i-C4Fg yields of 14% and 28%, respectively. The pyrolysis of CF3CHFCI resulted in slightly greater than 6% i-C4Fg yield, and CHF2Cl decomposition produced up to 6% i-C4Fg yield, wh...
Photosynthesis by isolated chloroplasts V. Phosphorylation and carbon dioxide fixation by broken chloroplasts

Abstract 1. 1. Photosynthetic esterification of inorganic phosphate into adenosine triphosphate, and reduction of CO2 to the level of carbohydrate, hitherto found to occur only in whole chloroplasts, have now been observed with chloroplasts broken by treatment with water. 2. 2. Broken chloroplasts retained only two of the three groups of enzymes contained in whole chloroplasts, namely, those controlling the photolysis of water and photosynthetic phosphorylation. At least some of the enzymes concerned in reduction of CO2 were leached out by treating the chloroplasts with water, with the result that CO2 fixation was completely abolished. 3. 3. On addition of the requisite cofactors, the capacity of broken chloroplasts for photosynthetic phosphorylation was the same as that of whole chloroplasts. 4. 4. The restoration to broken chloroplasts of the full capacity for photosynthetic CO2 fixation of whole chloroplasts required the addition of pyridine nucleotides, adenosine triphosphate, and the soluble enzymes removed by water treatment of whole chloroplasts. 5. 5. An additional several-fold increase in the rate of CO2 fixation by the reconstituted broken chloroplast system was obtained by the further addition of one of several compounds, principally phosphorylated sugars. This has resulted in a level of CO2 fixation by broken chloroplasts which is much higher than that obtained with whole chloroplasts.
Temporal patterns of seed use and availability in a guild of desert ants

. 1 Temporal patterns of seed use were studied from late winter to autumn in three species of seed-harvesting ants in the Sonoran Desert. Measures of effective foraging activity, dietary niche breadth and dietary niche overlaps were obtained each month and were tested for correlation with estimates of the available seed resource. 2 Seeds were the only numerically important type of food in the diets of all species. 3 The ants partitioned the resource according to both seed species and seed size, although there was considerable overlap. 4 Pheidole xerophila had the smallest forager body size and is a specialist on small seeds because it harvested them in greater proportion than their rank in the soils and expanded its diet to larger seeds only when the abundance of small seeds declined. 5 When the abundance of the small seeds of Bouteloua barbata decreased, the middle-sized ant, Veromessor pergandei, showed a decrease in foraging activity, increase in niche breadth, and a decrease in overlap with P.xerophila. 6 Seed size preferences of V.pergandei did not vary seasonally, except that during the month of highest seed abundance, V.pergandei showed no size preference. 7 Pogonomyrmex rugosus was the largest ant; it preferred larger seeds and was inactive when small seeds were most abundant. Seasonal foraging activity and niche parameters were random in relation to seed abundance. 8 We suggest that nocturnal foraging by P.rugosus during the summer months was a response to interference with diurnal foraging by either predation frorn horned lizards or competition from V.pergandei. 9 Seasonal abundance of small seeds explains most of the seasonal foraging patterns of P.xerophila and V.pergandei. The summertime abundance of larger seeds during years of adequate precipitation may account for the seasonal activity patterns of P.rugosus.
Prescribing home oxygen therapy. What the primary care physician needs to know.

Physicians who prescribe home oxygen therapy often find it difficult and time-consuming to complete the required certification of medical necessity because of a lack of in-depth knowledge concerning the Medicare requirements and treatment options. The Health Care Financing Administration (HCFA) now mandates that the physician or an employee of the physician complete the form to certify medical necessity (form HCFA-484); otherwise, the home oxygen supplier cannot be reimbursed for equipment and service. Since long-term oxygen therapy is essential to increase survival and to improve the quality of life for patients with hypoxemia due to chronic pulmonary disease, it is imperative that the primary care physician understand the indications and requirements for therapy and be able to order the most appropriate equipment for the therapeutic needs. This article is intended to provide the physician with the information needed to properly prescribe home oxygen therapy. ( Arch Intern Med . 1992;152:746-748)
Historical and Dialectical Perspectives on the Archaeology of Complexity in the Siin-Saalum (Senegal): Back to the Future?

Drawing on recent critiques of evolutionism, this article reviews the history of Iron Age studies in Siin-Saalum (Senegal) to examine the construction of African archaeological knowledge. From the 19th century to the 1980’s, analyses of complexity in Senegal have been animated by developmentalist views that have portrayed the regional past as a stagnant backwater. In the past 25 years, however, archaeological research has sought to redress these inaccuracies by exploring the diversity and idiosyncracy of African histories, and the processes behind sociopolitical change. These critical agendas can help us exploit the analytic potential of material culture to reincorporate African societies into the stream of world history, and to use the African past to reevaluate current scenarios of complexity and their applicability to various regions of the globe. To achieve these goals, however, and develop a fully self-reflexive archaeology in Senegal, researchers must eschew moral celebrations of African distinctness and strive instead to document how local pasts owe their particular qualities to complex political-economic articulations with other world societies. Concurrently, we must also attend to the dynamics of historical production in and out of guild circles, and consider our entanglement in the making of contemporary ‘culture wars.’ Because it is ideally suited to probe the historical and material depth of cultural differences and inequalities, archaeology must take a leading role in dispelling essentialist readings of Africa and promoting democratic knowledges about the continent.
Androgenic effects of oral contraceptives: Implications for patient compliance

Androgenic disorders have many negative physical effects. These effects may be caused by excess androgen (exogenous or endogenous) or by end-organ sensitivity to normal levels of androgens. Historically, androgenic progestins in oral contraceptives have also been associated with some of these negative effects. The most apparent signs of androgen excess are the external manifestations, including oily skin, acne, hirsutism, android obesity, and androgenic alopecia. Of equal concern are the potential metabolic disturbances associated with hyperandrogenicity. Unfavorable lipid profiles and increased incidence of diabetes and hypertension are very real threats to long-term health. In oral contraceptive users, external manifestations of androgenicity often lead to poor compliance, decreased efficacy, and discontinuation of oral contraceptive use, especially in the younger patient. With the introduction of the newer oral contraceptive formulations containing less androgenic progestins (norgestimate, desogestrel, gestodene), androgen-related effects have been reduced and better compliance is anticipated.
Ignition behavior of a fuel spray flowing in a tube

The ignition behavior of a spray flowing in a tube is numerically investigated. The ignition process is initiated by a localized heat source or a flame kernel. An hybrid finite-difference scheme is used to solve the two-phase equations. A consistent ignition criterion is obtained, which is shown to provide a sufficient ignition condition for all the cases considered. Results indicate the existence of an optimum droplet size and an optimum equivalence ratio for the minimum ignition energy. The optimum values vary with the mixture conditions such as droplet size, equivalence ratio, and fuel volatility. This is a significant result since the conclusions of earlier studies for the initially quiescent sprays are validated for the flowing situations.
An iterated estimation of the motion parameters of a rigid body from noisy displacement vectors

Concerns the estimation of the motion parameters of a rigid body from noisy point matches made on perspective views. A minimization problem which permits relatively robust parameter estimation and helps overcome poor zoom estimation when the field-of-view is small is formulated. It is assumed that the motion has a small rotary component, interframe differences are small, and the errors in the system are due to independently distributed errors in the components of the displacement vectors. A fast procedure for minimization is exposited, in which the parameter set is partitioned and conditional generalized least-squares formulas identified. Recursive application of these provides the search space for the minimization problem. Comparative results are presented using simulated data and displacement vectors obtained from an intensity-based matching algorithm. >
Analysis of metabolic flux phenotypes for two Arabidopsis mutants with severe impairment in seed storage lipid synthesis.

Major storage reserves of Arabidopsis (Arabidopsis thaliana) seeds are triacylglycerols (seed oils) and proteins. Seed oil content is severely reduced for the regulatory mutant wrinkled1 (wri1-1; At3g54320) and for a double mutant in two isoforms of plastidic pyruvate kinase (pkpβ1pkpα; At5g52920 and At3g22960). Both already biochemically well-characterized mutants were now studied by 13C metabolic flux analysis of cultured developing embryos based on comparison with their respective genetic wild-type backgrounds. For both mutations, in seeds as well as in cultured embryos, the oil fraction was strongly reduced while the fractions of proteins and free metabolites increased. Flux analysis in cultured embryos revealed changes in nutrient uptakes and fluxes into biomass as well as an increase in tricarboxylic acid cycle activity for both mutations. While in both wild types plastidic pyruvate kinase (PKp) provides most of the pyruvate for plastidic fatty acid synthesis, the flux through PKp is reduced in pkpβ1pkpα by 43% of the wild-type value. In wri1-1, PKp flux is even more reduced (by 82%), although the genes PKpβ1 and PKpα are still expressed. Along a common paradigm of metabolic control theory, it is hypothesized that a large reduction in PKp enzyme activity in pkpβ1pkpα has less effect on PKp flux than multiple smaller reductions in glycolytic enzymes in wri1-1. In addition, only in the wri1-1 mutant is the large reduction in PKp flux compensated in part by an increased import of cytosolic pyruvate and by plastidic malic enzyme. No such limited compensatory bypass could be observed in pkpβ1pkpα.
Strain-specific modification of lethality in fucose-deficient mice

The FX locus encodes an essential enzyme in the de novo pathway of GDP-fucose biosynthesis. Mice homozygous for a targeted mutation of the FX gene manifest a host of pleiotropic abnormalities including a lethal phenotype that is almost completely penetrant in heterozygous intercrosses on a mixed genetic background. Here we have investigated genetic suppression of FX-mediated lethality. Reduced recovery of heterozygous mice was observed while backcrossing the null FX allele to C57BL/6J (B6), but was less dramatic in an outcross to CASA/Rk and absent in an outcross to 129S1/SvImJ, indicating that genetic background modifies survival of FX+/) progeny. Substantial strain-specific differences in pre- and postnatal survival of FX)/) progeny were also detected in heterozygous crosses of C57BL/6J congenic, 129S1B6F1, and B6CASAF1 mice. Specifically, intrauterine survival of FX)/) mice was greatly increased during a heterozygous intercross on a uniform C57BL/6J genetic background compared with survival on a hybrid genetic background consisting of a mixture of C57BL/6J and 129S2/SvPas. In addition, statistically significant clustering of FX)/) progeny into litters and specific breeding cages was noted during a B6CASAF1 FX+/) intercross, suggesting a rare mechanism for modifier gene action in which parentally expressed genes define the phenotype, in this case the survival potential, of mutant offspring. Our results disclose that lethality in FX mutant mice is determined by one or more strainspecific modifier loci.
Specifying the Relationship Between Crime and Prisons

There is no scholarly consensus as to the proper functional form of the crime equation, particularly with regard to one critical, explanatory variable—prison population. The critical questions are whether crime and prison rates must be differenced, whether they are cointegrated, and whether they are simultaneously determined—whether crime and prison cause one another. To determine the proper specification, different researchers have applied unit-root, cointegration, and Granger tests to very similar data sets and obtained very different results. This has led to very different specifications and predictably different implications for public policy. These differences are more likely to be due to the methods used, rather than to real differences among the data sets. When the best available methods are used to identify the proper specification for a panel of U.S. states, results are fairly clear. Crime rates and prison populations are close to unit-root; crime and prison are not cointegrated; crime clearly affects subsequent prison populations. Thus the best specification of the crime equation must rely on differenced data and instrumental variables. Alternative specifications run a substantial risk of spurious results.
Morphological changes in the thalamus and neocortex of the cat brain after a restricted unilateral fetal neocortical lesion

In order to study the response of the brain to injury during early development, the neocortex of ten fetal kittens was lesioned at age E43-48, in either the frontal (n = 8) or parieto-occipital (n = 2) areas. The thalamus and neocortex of the lesioned animals were analyzed using quantitative morphometry and compared to intact control cats (n = 10). Ipsilaterally, the volumes of the remaining neocortex and of the thalamus were 26.5% and 25.7% smaller, respectively (P < 0.05). Contralaterally, the neocortex did not change in volume, whereas the thalamus tended to be smaller by a mean of 11.1%. Ipsilaterally, in all four thalamic nuclei studied, the neuronal and glial cell packing densities (NCPD and GCPD) and the cross sectional area of neuronal somata did not differ between lesioned and intact animals except for the principal ventromedial nucleus, where the GCPD was significantly lower (P < 0.05) in lesioned animals. Contralaterally, the NCPD and GCPD did not show any differences between groups, except for the principal ventromedial nucleus, in which the GCPD was lower in lesioned cats (P < 0.05). Furthermore, in the contralateral basal ventromedial nucleus, the cross sectional area of the neuronal somata was smaller in lesioned than in intact animals (P < 0.01). These results indicate loss of neurons and glia in the ipsilateral thalamus and probably in the neocortex. Since, at the time of the cortical resection, transient reciprocal thalamosubplate connections have been established in the cat, the lesion-induced deprivation of subplate target neurons and cortical inputs probably precluded the survival of a substantial number of developing thalamic neurons. In the cortex the hypothetical loss of neurons may, at least partly, be attributed to lesion-induced elimination of target neurons before establishment of corticocortical connections.
Frequency analysis of accommodation: single sinusoids.

We present an experimental frequency analysis of a neurological control system, the accommodation system, using single sinusoids. Also, by means of continual experimental calibration and full coverage of one subject's dynamic range, we demonstrate an AC nonlinearity saturation, which probably lies in the motor-response portion of the system; in contrast to the switching-mode nonlinearity, which probably lies in the sensory-processing portion. We offer our findings as a basis for further models. In addition, our results can be compared with studies using multiple sinusoids and transients to document how the different aspects of the accommodation system are realized given their different input conditions.
Stimulation of protein synthesis in cytochalasin B-enucleate human fibroblasts by dexamethasone and insulin.

Abstract Enucleation of human diploid fibroblasts with cytochalasin B (CB) was used to study the relative roles of cytoplasm and nucleus in cellular responses to dexamethasone and insulin. Cultures which contained a large fraction of enucleate cells responded to both of these hormones by an increase in protein synthesis similar to that observed in controls. Quantitative autoradiography indicated that individual enucleated cells displayed significantly increased protein synthesis in response to both insulin and dexamethasone, but not to estradiol. The results suggest that specific steroids may exert effects upon cell cytoplasm independent of nuclear involvement. It is suggested that the observed enhancement of protein synthesis by dexamethasone may be due to stimulation of membrane transport processes.
Cognitive abilities profiles of Caucasian vs Japanese subjects in the Hawaii family study of cognition

Abstract General intelligence (the unrotated first principal component) was partialled out of the cognitive abilities factors—verbal ability, spatial ability, perceptual speed, and visual memory—obtained for the 15 tests of cognitive abilities used in the Hawaii Family Study of Cognition (HFSC). The resulting cognitive abilities profiles indicated that HFSC subjects of Caucasian ancestry scored higher relative to subjects of Japanese ancestry on the verbal and visual memory factors, but lower on the spatial and perceptual speed factors. This ethnic group difference in the shape of the cognitive abilities profiles was found to be highly consistent across sexes and generations, in spite of the large mean differences across these groups in factor scores.
Integrated model-based retargeting and optical proximity correction

Conventional resolution enhancement techniques (RET) are becoming increasingly inadequate at addressing the challenges of subwavelength lithography. In particular, features show high sensitivity to process variation in low-k1 lithography. Process variation aware RETs such as process-window OPC are becoming increasingly important to guarantee high lithographic yield, but such techniques suffer from high runtime impact. An alternative to PWOPC is to perform retargeting, which is a rule-assisted modification of target layout shapes to improve their process window. However, rule-based retargeting is not a scalable technique since rules cannot cover the entire search space of two-dimensional shape configurations, especially with technology scaling. In this paper, we propose to integrate the processes of retargeting and optical proximity correction (OPC). We utilize the normalized image log slope (NILS) metric, which is available at no extra computational cost during OPC. We use NILS to guide dynamic target modification between iterations of OPC. We utilize the NILS tagging capabilities of Calibre TCL scripting to identify fragments with low NILS. We then perform NILS binning to assign different magnitude of retargeting to different NILS bins. NILS is determined both for width, to identify regions of pinching, and space, to locate regions of potential bridging. We develop an integrated flow for 1x metal lines (M1) which exhibits lesser lithographic hotspots compared to a flow with just OPC and no retargeting. We also observe cases where hotspots that existed in the rule-based retargeting flow are fixed using our methodology. We finally also demonstrate that such a retargeting methodology does not significantly alter design properties by electrically simulating a latch layout before and after retargeting. We observe less than 1% impact on latch Clk-Q and D-Q delays post-retargeting, which makes this methodology an attractive one for use in improving shape process windows without perturbing designed values.
LIFE REINSURANCE POOLS

THE GREATER part of the reinsurance ceded by American life insurance companies is assumed by eight American companies that aggressively seek this type of business.' A relatively small percentage of the total, which is nevertheless a considerable volume of insurance' is reinsured under reciprocal agreements entered into by twenty life insurance companies that do not seek to assume reinsurance from any other companies. The twenty companies are divided into four groups. These groups through which the participating companies mutually agree to cede reinsurance to each other and to assume reinsurance from each other are known as reinsurance "pools."3 It is the purpose of this paper to present the factors that lead life insurance companies to cede and assume reinsurance through reinsurance pools, to summarize the essential characteristics of the twenty life insurance companies4 in the United States that are members of reinsurance pools, and to illustrate the nature of the operations of life reinsurance pools by describing the operations of one of the four pools.