cssi/SciSciGPT-SciSciNet huggingface dataset:
The role of social support in the association between childhood trauma and depression among HIV-infected and HIV-uninfected individuals.

Childhood trauma (CT) – emotional, physical or sexual abuse, or emotional or physical neglect – has been associated with HIV infection and can lead to poor health outcomes and depression in adultho...
Won't You Be My Neighbor? Muscle Stem Cells Recruit Endothelial Cells to Their Niche.

The maintenance of a pool of quiescent satellite cells (muscle stem cells) is necessary for long-term muscle health. In this issue of Cell Stem Cell, Verma et al. (2018) show that satellite cells recruit endothelial cells to create a vascular niche and that cross-talk between endothelial and satellite cells is vital for replenishment and maintenance of quiescent satellite cells.
Confidential Sourcing and Anonymous Documents

Confidential sources and confidential documents can be critical to high-quality journalism when there are too few transparent sources to adequately inform a news story. Moreover, the legal protections that U.S. journalists receive from most state’s “shield laws” are one of the most symbolic aspects of professionalization (or professionalism) that journalists possess because of their similarity to established professions’ confidentiality protections such as doctor-patient confidentiality and attorney-client privilege. Nonetheless, good journalists typically limit their use of confidential sources and documents because their audience loses transparency and because sources often have ulterior motives that pose significant risks to the effects of the reporting. The purpose of this chapter is to clarify the guiding principles justifying the use of confidential sources and documents, while also considering limitations.
Adopting tipping-point theory to transcriptome profiles unravels disease regulatory trajectory

Tipping-point models have had success identifying transcriptional critical-transition signal (CTS) in tumor phenotypes using time-course data. Can these mathematical models be adopted to cross-sectional transcriptome profiles? Furthermore, can the CTS analysis that characterizes tumor progression be applied to lncRNA-expression patterns? This study introduces a novel network-perturbation signature (NPS) scoring scheme to model a phenotype-defined tumor regulatory system. Applying NPS to neuroblastoma transcriptome of two patient populations yielded two CTSs that reproducibly identified a critical system transition between the low-risk and a high-risk state. The coherent expression pattern of one specific CTS, consisting of mRNA and lncRNA components, showed prognostic significance. Associating GWAS-scans with the CTS unveiled four overlooked intergenic loci and five genes with promising clinical significance. Additionally, a new mechanism of CTS-amplifier is proposed, modeling how CTS-transcript fluctuation response to complex master regulators such as c-MYC and HNF4A uniquely in the transition state. Overall, NPS is a powerful computational approach that provides a breakthrough in phenomenological analysis of collective regulatory trajectory by applying tipping-point theory to -omics data.nnHighlightsO_LIWe adopt tipping-point theory to identify distribution-transition in disease regulatory statesnC_LIO_LICritical transcriptional transition happens between low-risk and a high-risk neuroblastoma statesnC_LIO_LIA critical transition signal (CTS) based on coherent expression of genes and lncRNAs shows prognostic significancenC_LIO_LIGWAS-scans with the CTS unveiled five overlooked genes and four lncRNAs with promising clinical implicationsnC_LIO_LIWe propose a CTS-amplifier model that unveils complex but mastering trans-regulation in diseasenC_LI
Concordant Validity of a Digital Peak Cough Flow Meter to Assess Voluntary Cough Strength in Individuals with ALS.

Peak cough flow represents an important metric directly related to the physiologic ability of an individual to defend the airway or expel tracheal aspirate. Given the high prevalence of dysphagia and dystussia in individuals with amyotrophic lateral sclerosis (ALS) and recent findings that the expiratory phase of voluntary cough is significantly impaired in ALS individuals, we aimed to determine the reproducibility of an affordable, portable peak cough flow (PCF) meter for the assessment of cough production in individuals with ALS. 109 individuals with ALS completed voluntary cough testing using both the research cough spirometry equipment and a digital peak cough flow meter. Maximum peak expiratory cough flow rates were obtained from each device. Analyses included paired t test, Pearson’s correlation, and Lin’s concordance correlation to determine the degree of agreement and reproducibility between cough measurement devices (alpha = 0.05). Mean differences between peak cough flow test values (L/min) across instruments were not statistically significant (mean difference = − 2.93; 95% CI − 18.67, 12.82; p = 0.713). PCF values obtained from the digital peak cough flow meter and the research cough spirometry equipment were strongly associated (r = 0.826, p < 0.000) and demonstrated a high level of agreement and reproducibility (ρc = 0.824, 95% CI 0.754, 0.876). These data validate the use of an inexpensive and portable digital peak cough flow device to index peak cough flow strength in individuals with ALS. This assessment could easily be incorporated into a multidisciplinary ALS clinical setting to index the physiologic ability of an individual to protect the airway.
Adversarial tensor factorization for context-aware recommendation

Contextual factors such as time, location, or tag, can affect user preferences for a particular item. Context-aware recommendations are thus critical to improve both quality and explainability of recommender systems, compared to traditional recommendations that are solely based on user-item interactions. Tensor factorization machines have achieved the state-of-the-art performance due to their capability of integrating users, items, and contextual factors in one unify way. However, few work has focused on the robustness of a context-aware recommender system. Improving the robustness of a tensor-based model is challenging due to the sparsity of the observed tensor and the multi-linear nature of tensor factorization. In this paper, we propose ATF, a model that combines tensor factorization and adversarial learning for context-aware recommendations. Doing so allows us to reap the benefits of tensor factorization, while enhancing the robustness of a recommender model, and thus improves its eventual performance. Empirical studies on two real-world datasets show that the proposed method outperforms standard tensor-based methods.
Vancomycin dosing in hospitalized children by weight status: a systematic review

Purpose In children, providers commonly use total body weight for calculating the appropriate medication dose. However, variability in body composition may cause inaccurate dosing. Children with obesity have greater fat mass, higher total body water percentage, and greater fat-free mass than children at a normal weight. Vancomycin is a commonly prescribed medication in hospitalized pediatric patients that carries potential for significant harm with both overdosing or underdosing. This study aimed to determine whether children having overweight or obesity have increased vancomycin levels compared with children …
Pulse Timing Jitter Estimated From Optical Phase Noise in Mode-Locked Semiconductor Quantum Dash Lasers

The determination of timing jitter obtained from optical phase noise measurements is investigated in InAs/InP quantum dash Fabry–Perot mode-locked coherent comb lasers with different pulse repetition rates. The results are compared with those determined through a direct measurement of the first harmonic of the RF power spectrum. Very good agreement is achieved. The ability to measure the timing jitter from optical phase noise is not restricted by the repetition rate of the laser being studied, allowing it to be applied to extremely high repetition rate lasers. Using these lasers we demonstrate 5.4 Tbit/s (PAM-4 48 × 28 GBaud PDM) and 10.3 Tbit/s (16 QAM 56 × 23 GBaud PDM) aggregate data transmission capacity. The ultra-low timing jitter exhibited by these devices make them excellent sources for multi-terabit optical networks.
Hypohidrosis as an immune-related adverse event of checkpoint inhibitor therapy.

Background: Immune checkpoint blockade therapies including cytotoxic-T-lymphocyte antigen 4 (CTLA-4) and programmed cell death protein-1 (PD-1) inhibitors have become indispensable tools for treating melanoma and other cancers. An increasing number of diverse cutaneous adverse reactions to immunotherapy have been documented in the literature and have been reported to affect up to 40% of patients treated with targeted therapies. Method & results: Herein, we report a case of a patient with metastatic melanoma treated with checkpoint inhibitor therapy who developed vitiligo, gastritis and hepatitis, all identified as adverse immune events and attributable to his immunotherapy regimen. He subsequently developed acquired idiopathic generalized hypohidrosis with biopsy of lesional skin demonstrating a peri-eccrine lymphocytic infiltrate. Conclusion: These findings suggest this acquired generalized hypohidrosis represents a lymphocyte-mediated adverse immune event related to this patient's checkpoint inhibitor therapy.
Accuracy of Touch-Based Registration During Robotic Image-Guided Partial Nephrectomy Before and After Tumor Resection in Validated Phantoms.

Aim: Image-guided surgery (IGS) allows for accurate, real-time localization of subsurface critical structures during surgery. No prior IGS systems have described a feasible method of intraoperative...
Comparison of FEA simulations and experimental results for as-built additively manufactured dogbone specimens

Parts built using fused deposition modeling (FDM—an additive manufacturing technology) differ from their design model in terms of their microstructure and material properties. These differences lead to a certain amount of ambiguity regarding the structure, strength, and stiffness of the final FDM part. Increasing use of FDM parts as end use products necessitates accurate simulations and analyses during part design. However, analysis methods such as finite element analysis, are used for analysis of continuum models, and may not accurately represent the non-continuous non-linear FDM parts. Therefore, it is necessary to determine the accuracy and precision of FEA for FDM parts. The goal of this study is to compare FEA simulations of the as-built geometries with the experimental tests of actual FDM parts. Dogbone geometries that include different infill patterns are tested under tensile loading and later simulated using FEA. This study found that FEA results are not always an accurate or reliable means of predicting FDM part behaviors.
CENTRORADIALIS maintains shoot meristem indeterminacy by antagonizing THORN IDENTITY1 in Citrus.

Summary Differential regulation of stem cell activity in shoot meristems contributes to the wide variation in shoot architecture. 1 , 2 , 3 In most Citrus species, a thorn meristem and a dormant axillary meristem co-localize at each leaf base, offset from each other in a spiral phyllotactic pattern. We recently identified THORN IDENTITY1 (TI1) and THORN IDENTITY2 (TI2), encoding TEOSINTE BRANCHED1/CYCLOIDEA/PCF (TCP) transcription factors, as necessary for the termination of meristem proliferation and concomitant thorn production in Citrus. 4 However, how the dormant axillary meristem at the same leaf axil maintains stem cell activity is still unknown. The phosphatidylethanolamine-binding protein (PEBP)-type transcription factors CENTRORADIALIS (CEN) and TERMINAL FLOWER1 (TFL1) maintain inflorescence meristem indeterminacy in many plant species by antagonizing floral meristem identity regulators. 5 , 6 , 7 , 8 , 9 Here, we show that, in Citrus, Citrus CEN (CsCEN) maintains vegetative axillary meristem indeterminacy by antagonizing TI1. CsCEN is expressed in the axillary meristem, but not in the thorn meristem. Disruption of CsCEN function results in termination of the stem cell activity and conversion of dormant axillary meristems into thorns, although ectopic overexpression of CsCEN represses TI1 expression and converts thorns into dormant buds, a phenotype similar to the ti1 mutant. We further show that CsCEN interacts with Citrus FD (CsFD) to repress TI1 expression. CsCEN activity depends on the function of TI1 and TI2, as mutations in TI1 and TI2 rescue the cscen mutant phenotype. We suggest that the antagonistic roles of CsCEN and TI1 define the pattern of axillary meristem determinacy, which shapes vegetative Citrus tree shoot architecture.
Hands-On Exploration of Ocean Acidification with a Living Calcifier

This hands-on lab allows students to explore concepts and quantify effects of ocean acidification. Many laboratory activities simplify ocean acidification through computer simulations or dripping acid on nonliving materials (e.g., sea shells) but do not provide adequate opportunities for students to measure, inquire, or see real consequences for living organisms. Thus, we developed this low-cost, easily accessible experiment to imitate ocean acidification on living, calcifying organisms.
Pure-Chance Jobs vs. A Labor Market: The Impact on Careers of a Random Serial Dictatorship for First Job Seekers

Does a worker's first job affect her long-run career? Do any such "first job effects" vary across workers of different types? If so, can policy improve upon a "free" labor market by altering initial matches with employers? We begin to study the impact of market design on the performance of entry-level labor markets, by comparing 20 years when Norway assigned doctors to their first job---residencies---through a Random Serial Dictatorship, with the post-2013 era when the RSD mechanism was replaced with decentralized job-finding. We first estimate the consequences for long-run earnings of different employers for male and female workers. We do so by exploiting RSD-generated random, individual level variation in workers' initial choice set over employers. We then decompose preferences over employers into a component that is due to first job effects and another that is due to the "amenity value" workers of a given type associate with employers of a given type. Finally, we show how realized first job effects, amenity values, and overall worker welfare differ, for each group and in total, in a decentralized labor market compared to a randomized-choice-sets system, by describing how worker-employer matches changed after 2013.
Introspective Faculty Assessment of Self Leadership

This article describes a faculty self-leadership study and its impact on outcomes—extra effort, effectiveness, and satisfaction. The research questions asked faculty’s perceptions of classroom lead...
Dietary Intake and Energy Expenditure in Breast Cancer Survivors: A Review

Many breast cancer survivors (BCS) gain fat mass and lose fat-free mass during treatment (chemotherapy, radiation, surgery) and estrogen suppression therapy, which increases the risk of developing comorbidities. Whether these body composition alterations are a result of changes in dietary intake, energy expenditure, or both is unclear. Thus, we reviewed studies that have measured components of energy balance in BCS who have completed treatment. Longitudinal studies suggest that BCS reduce self-reported energy intake and increase fruit and vegetable consumption. Although some evidence suggests that resting metabolic rate is higher in BCS than in age-matched controls, no study has measured total daily energy expenditure (TDEE) in this population. Whether physical activity levels are altered in BCS is unclear, but evidence suggests that light-intensity physical activity is lower in BCS compared to age-matched controls. We also discuss the mechanisms through which estrogen suppression may impact energy balance and develop a theoretical framework of dietary intake and TDEE interactions in BCS. Preclinical and human experimental studies indicate that estrogen suppression likely elicits increased energy intake and decreased TDEE, although this has not been systematically investigated in BCS specifically. Estrogen suppression may modulate energy balance via alterations in appetite, fat-free mass, resting metabolic rate, and physical activity. There are several potential areas for future mechanistic energetic research in BCS (e.g., characterizing predictors of intervention response, appetite, dynamic changes in energy balance, and differences in cancer sub-types) that would ultimately support the development of more targeted and personalized behavioral interventions.
Circulating Sex Hormones and Risk of Colorectal Adenomas and Serrated Lesions in Men.

Background Sex hormones have been implicated in the etiology of colorectal neoplasia in women for over 40 years, but there has been very little investigation of the role of these hormones in men. Methods Using data from an adenoma chemoprevention trial, we conducted a secondary analysis to examine serum hormone levels (testosterone, androstenedione, dehydroepiandrosterone-sulfate (DHEA-S) and sex hormone-binding globulin (SHBG) and risk of colorectal precursors in 925 men. Multivariable logistic regression models were fit to evaluate adjusted associations between hormone levels and risk of "low" (single tubular adenoma 2 adenomas of any size). Results Overall, levels of free testosterone, total testosterone, androstenedione, DHEA-S or SHBG were not associated with either "low" or "high-risk" early precursor lesions in the colorectum. Conclusions These findings do not support the role of sex hormones in early colorectal neoplasia among men. Impact This large prospective study address a missing gap in knowledge by providing information on the role of sex hormones in colorectal neoplasia in males.
DNA-alkylating events associated with nitrogen mustard based anticancer drugs and the metabolic byproduct Acrolein

Abstract The nitrogen mustard anticancer drugs are widely used for treating many forms of cancer. However, a number of toxic side effects, including secondary tumors, limit their clinical utility. There is strong evidence that the effectiveness for killing cancer cells (cytotoxicity) of these drugs is directly related to the ability of their metabolites to form interstrand DNA crosslinks. These crosslinks are formed by the sequential alkylation of two bases on complementary DNA strands. Other products, including monoalkylated adducts and intrastrand crosslinks are much less cytotoxic, and can mutate the DNA in normal cells leading to the formation of secondary tumors. The nitrogen mustards have a complex DNA-alkylation chemistry. They form monoalkylation adducts at a number of different sites on DNA and the predominant lesions vary between mustards and are strongly modulated by conjugation with DNA-targeting groups including intercalators, minor groove binders, and triplex-forming DNA oligomers. Only a small fraction of the DNA-alkylation events proceed to the formation of the therapeutically useful, highly cytotoxic crosslinks. For this reason there is considerable ongoing research to improve the efficiency of crosslink formation, and reduce the mutagenic effects of the other mustard-induced lesions. The phosphoramide mustard prodrugs including cyclophosphamide and ifosfamide, produce acrolein as a metabolic byproduct. Like the mustards themselves, acrolein has a complex DNA-alkylation chemistry, leading to a diversity of DNA adducts.
THE ACUTE RESPIRATORY DISTRESS SYNDROME IN CHILDREN: RECENT UMMC EXPERIENCE

The acute respiratory distress syndrome (ARDS) is now well recognized as a cause of respiratory failure in children and is associated with a high mortality rate. We retrospectively reviewed all cases of ARDS managed in our multidisciplinary pediatric intensive care unit (PICU) from 1994 to 1998 in order to identify predisposing conditions, outcomes, complications, recent trends in therapy, and resource utilization. Twenty-seven children were identified representing approximately 1% of all intensive care admissions. Sepsis was the most common predisposing illness and air leak complicated treatment in 60%. Mortality was 30% and was most often due to non-respiratory causes. High-frequency oscillatory ventilation (HFOV) was frequently utilized and felt to be beneficial in most cases. On average, survivors required mechanical ventilation for five weeks and hospitalization for nine weeks. We conclude that despite our comparatively low mortality rate, ARDS remains a significant challenge to the pediatric intensivist. We speculate that HFOV may be an important factor in reducing mortality.
The Face of Controversy

Neuroscientists have long puzzled over whether our brains process and represent information according to modules (precise brain areas respond to separate and specific stimuli) or in a distributed fashion (different brain areas cooperate to represent the same stimulus). In an enlightening Perspective, [Cohen and Tong][1] discuss two fascinating neuroimaging studies that identify areas of the human brain that represent the perception of human faces and other parts of the human body ([ Downing et al .][2], [ Haxby et al .][3]). As the Perspective authors explain, one group invokes modularity and the other group invokes distributed representation to explain their results, raising the debate about modularity versus distributed representation to new heights. [1]: http://www.sciencemag.org/cgi/content/full/293/5539/2405 [2]: http://www.sciencemag.org/cgi/content/short/293/5539/2470 [3]: http://www.sciencemag.org/cgi/content/short/293/5539/2425
Improvements to the IBM speech activity detection system for the DARPA RATS program

In this paper we describe improvements to the IBM speech activity detection (SAD) system for the third phase of the DARPA RATS program. The progress during this final phase comes from jointly training convolutional and regular deep neural networks with rich time-frequency representations of speech. With these additions, the phase 3 system reduces the equal error rate (EER) significantly on both of the program's development sets (relative improvements of 20% on dev1 and 7% on dev2) compared to an earlier phase 2 system. For the final program evaluation, the newly developed system also performs well past the program target of 3% P miss at 1% P fa with a performance of 1.2% P miss at 1% P fa and 0.3% P fa at 3% P miss .
Purification of an ultraviolet-inducible, damage-specific DNA-binding protein from primate cells.

A UV-inducible, damage-specific DNA-binding (DDB) protein with high affinity for double-stranded UV-irradiated DNA has been identified recently in monkey kidney (CV-1) cells (Hirschfeld, S., Levine, A. S., Ozato, K., and Protic, M. (1990) Mol. Cell. Biol. 10, 2041-2048). We have now purified the DDB protein from extracts of CV-1 cells using hydroxylapatite, phosphocellulose, Mono S, and DNA-affinity column chromatography. The DDB activity, either from mock-treated or UV-induced cells, is heterodisperse in column chromatography, and separation of three forms of the protein was obtained on a phosphocellulose column. Analysis of purified preparations by sodium dodecyl sulfate-polyacrylamide gel electrophoresis demonstrated that greater than 90% of all three forms is a protein of approximately 126 kDa. The size of the native DDB protein was deduced from gel filtration and native polyacrylamide gel electrophoresis to be approximately 210 kDa, which suggests that the native DDB protein in solution is a homodimer. Preparations of partially purified DDB protein from UV-treated cells have enhanced levels of DDB activity and the protein when compared with similar preparations from mock-treated cells. This damage-recognition protein, alone or in conjunction with other subunits, may be of general importance for the initial recognition of DNA damage in mammals.
Bilateral simultaneous tubal pregnancy

Abstract Attention is called to some points of difficulty in verifying reported cases of multiple simultaneous tubal pregnancy. The few requirements for acceptance of cases are stated. The source material of 76 verifiable cases is given. A third case is presented of simultaneous twin pregnancy in one tube and a single pregnancy in the other tube.
High Speed Data Bus Active Coupler

The author discusses the Unisys HSDB (high speed data bus) active coupler which provides a typical 13-dB power margin for HSDB systems installed in military aircraft. This high-power margin ensures reliable HSDB operation through fiber-optic component degradation. The active coupler performs optical amplification and active reshaping functions such that an incoming signal is modified only in amplitude. Signal distortion and jitter are removed by a retiming ASIC (application-specific integrated circuit). The active coupler is modular in design, and plug-in growth for a 38*38 user interface is available. The active coupler achieves better than -27 dBm sensitivity at 5*10/sup -11/ bit error rate and outputs -8 to -12 dBm optical power. The active coupler unit weighs only 6.25 lbs and has a predicted mean time between failure of over 21000 h. >
Distribution and density of monoamine receptors in the primate visual cortex devoid of retinal input from early embryonic stages

Developmental mechanisms that regulate the areal and laminar distribution of various macromolecules, including neurotransmitter receptors in the cerebral cortex, are not known. In the present study, we examined the development of monoaminergic receptors in the rhesus monkey striate and peristriate visual cortex in the absence of input from the retina. Binocular enucleation was performed between embryonic days E60 and E81, prior to the ingrowth of geniculocortical fibers into the cortical plate and before genesis of the granular and supragranular layers of the visual cortex. The animals were delivered at term (E165) and sacrificed at 2 or 12 months of age, and their brains frozen and the occipital lobes cut at 20 microns in the coronal plane. Cortical binding of 3H-clonidine, 125I-pindolol, 3H-5-HT, 3H-ketanserin, 3H- spiperone, 3H-SCH23390, and 3H-prazosin that label various monoamine receptors were autoradiographically visualized and quantified using a computer imaging system. All radioligands displayed specific laminar patterns in the striate and prestriate areas in both groups of animals. The areal and laminar distribution in the anophthalmic monkeys was similar to that in the controls. Significantly, in all enucleated animals, just as in the controls, a particularly high density of 3H- clonidine and 3H-prazosin was observed in the sublayers of layer IV involved in color vision. The present results show that the monoamine receptors in primate visual cortex can establish and maintain distinct laminar and areal patterns in the absence of activity or molecular cues originated from the retina, and provide new insight into the cortical consequences of secondary congenital anophthalmia.
Crystal Structure and Amide H/D Exchange of Binary Complexes of Alcohol Dehydrogenase from Bacillus stearothermophilus: Insight into Thermostability and Cofactor Binding

The crystal structure of NAD + -dependent alcohol dehydrogenase from Bacillus stearother- mophilus strain LLD-R (htADH) was determined using X-ray diffraction data at a resolution of 2.35 A. The structure of homotetrameric htADH is highly homologous to those of bacterial and archaeal homotetrameric alcohol dehydrogenases (ADHs) and also to the mammalian dimeric ADHs. There is one catalytic zinc atom and one structural zinc atom per enzyme subunit. The enzyme was crystallized as a binary complex lacking the nicotinamide adenine dinucleotide (NAD + ) cofactor but including a zinc- coordinated substrate analogue trifluoroethanol. The binary complex structure is in an open conformation similar to ADH structures without the bound cofactor. Features important for the thermostability of htADH are suggested by a comparison with a homologous mesophilic enzyme (55% identity), NAD + -dependent alcohol dehydrogenase from Escherichia coli. To gain insight into the conformational change triggered by NAD + binding, amide hydrogen-deuterium exchange of htADH, in the presence and absence of NAD + , was studied by HPLC-coupled electrospray mass spectrometry. When the deuteron incorporation of the protein-derived peptides was analyzed, it was found that 9 of 21 peptides show some decrease in the level of deuteron incorporation upon NAD + binding, and another 4 peptides display slower exchange rates. With one exception (peptide number 8), none of the peptides that are altered by bound NAD + are in contact with the alcohol-substrate-binding pocket. Furthermore, peptides 5 and 8, which are located outside the NAD + -binding pocket, are notable by displaying changes upon NAD + binding. This suggests that the transition from the open to the closed conformation caused by cofactor binding has some long- range effects on the protein structure and dynamics.
Invisible Houston: The Black Experience in Boom and Bust

Houston was Boomtown USA in the 1970s, growing through tremendous immigration of people and through frequent annexation of outlying areas. But in the shadow of the high-rise "petropolis" was another city ignored by and invisible to Houston municipal boosters and the national media. Black Houston, the largest black community in the South, remained largely untouched by the benefits of the boom but bore many of the burdens. Robert D. Bullard systematically explores major demographic, social, economic, and political factors that helped make Houston the "golden buckle" of the Sunbelt. He then chronicles the rise of Houston's black neighborhoods and analyzes the problems that have accrued to the black community over the years, concentrating on the boom era of the 1970s and the dwindling of the economy and of government commitment to affirmative action in the late 1980s. Case studies conducted in Houston's Third Ward--a microcosm of the larger black community--provide data on housing patterns, discrimination, pollution, law enforcement, and leadership, issues that the author discusses and relates to the larger ones of institutional racism, poverty, and politics. During Houston's rapid growth, freeways were built over black neighborhoods and municipal services were stretched away from the inner city and poverty pockets to the new, far-flung, and mostly white city limits. Businesses thrived, but many jobs called for advanced education and skills, while black youth still suffered from inadequate schools, inexperienced teachers, and, later, unemployment rates nearly double those of whites. When the oil-based economy collapsed in the early eighties, many blacks again bore a heavier share of the burdens. Invisible Houston describes the rich cultural history of the South's largest black community and analyzes the contemporary issues that offer the chance for black Houston to become visible to itself, to the larger community, and to the nation.
Proliferation of cardiomyocytes derived from human embryonic stem cells is mediated via the IGF/PI 3-kinase/Akt signaling pathway

Cardiomyocytes from common experimental animals rapidly exit the cell cycle upon isolation, impeding studies of basic cell biology and applications such as myocardial repair. Here we examined proliferation of cardiomyocytes derived from human and mouse embryonic stem (ES) cells. While mouse ES cell-derived cardiomyocytes showed little proliferation, human cardiomyocytes were highly proliferative under serum-free conditions (15-25% BrdU+/sarcomeric actin+). The cells exhibited only a small serum dose-response, and proliferation gradually slowed with increasing differentiation of the cells. Neither cell density nor different matrix attachment factors affected cardiomyocyte proliferation. Blockade of phosphatidylinositol 3-kinase (PI 3-kinase) and Akt significantly reduced cardiomyocyte proliferation, whereas MEK inhibition had no effect. Antibody blocking of the insulin-like growth factor-1 (IGF-1) receptor significantly inhibited cardiomyocyte proliferation, while addition of IGF-1 or IGF-2 stimulated cardiomyocyte proliferation in a dose-dependent manner. Thus, cardiomyocytes derived from human ES cells proliferate extensively in vitro, and their proliferation appears to be mediated primarily via the PI 3-kinase/Akt signaling pathway, using the IGF-1 receptor as one upstream activator. This system should permit identification of regulatory pathways for human cardiomyocyte proliferation and may facilitate expansion of cardiomyocytes from human ES cells for therapeutic purposes.
Sedimentary environments within a glaciated estuarine-inner shelf system: Boston Harbor and Massachusetts Bay

Abstract Three modern sedimentary environments have been identified and mapped across the glaciated Boston Harbor estuary and adjacent inner shelf of Massachusetts Bay by means of an extensive set of sidescan sonar records and supplemental bathymetric, sedimentary, subbottom and bottom-current data. 1. (1) Environments of erosion and nondeposition appear on the sonographs either as patterns with isolated reflections (caused by outcrops of bedrock, glacial drift, and coastal plain rocks) or as patterns of strong backscatter (caused by coarse-grained lag deposits). Sediments in these environments range from boulder fields to gravelly sands with megaripples. Inside the harbor, areas of erosion or nondeposition are found primarily near mainland and insular shores and within constricted tidal channels, whereas, on the shelf, they are present over extensive areas of hummocky topography near the coast and atop local bathymetric highs offshore. 2. (2) Environments of sediment reworking are characterized on the sonographs by patterns with patches of strong to weak backscatter caused by a combination of erosional and depositional processes. These environments have diverse grain sizes that range from sandy gravels to muds. Within the harbor, the locations of reworked sediments are uncorrelated with the bottom topography, but, on the shelf, they are found on the lower flanks of bathymetric highs, within broad lows and in relatively deep water (30–50 m). 3. (3) Environments of deposition are depicted on the sonographs as uniform patterns of weak backscatter. These areas contain relatively fine-grained muddy sands and muds. Inside the harbor, depositional environments are found over extensive subtidal flats and within sheltered depressions, whereas, on the shelf, they are restricted to broad lows mainly in deep water. The extreme patchiness of modern sedimentary environments within the Boston Harbor-Massachusetts Bay system reflects the interaction between the irregular bottom topography and both geologic and oceanographic processes. The estuarine part of the system is an effective trap for fine-grained detritus because of its protected nature, low wave climate, and large supply of sediments. The open shelf, however, is largely mantled by winnowed and sorted sediments as a result of erosion during past sea-level fluctuations, sediment resuspension and transport by modern waves and currents, and a spatially variable supply of fine-grained sediments.
Automated determination of fluoride using silicone-facilitated diffusion

An automated procedure for the determination of fluoride in biological fluids that uses silicone-facilitated diffusion at room temperature to separate fluoride from other sample constituents is described. Fluoride is measured by its ability to quench the fluorescence of a morin-thorium complex. The procedure appears to be free of significant interferences and is capable of measuring fluoride in the submicromolar range.
Thalamic connections with limbic cortex. II. Corticothalamic projections

The corticothalamic projections from the cat limbic cortex have been investigated with anterograde and retrograde axonal transport techniques. Five limbic cortical areas—the anterior limbic area, the cingular area, the granular and dysgranular retrosplenial areas, and the presubiculum—were identified on the basis of their cytoarchitecture. Emphasis was placed on determining the laminar distribution of the cells of origin of the efferent projections, the projection pathways, and the sites of termination within the thalamus. Projections to the thalamus originate in layers V and VI of limbic cortex. In the cingular region the cells of origin are predominantly in layer V and to a lesser extent in layer VI, while the majority of cells projecting from the more caudal retrosplenial areas and presubiculum are in layer VI. There are two fiber pathways from each cortical area to the thalamus. One system of fibers passes through the internal capsule and lateral thalamic peduncle, and a second system travels in the cingulate fasciculus before piercing the corpus callosum to join the postcommissural fornix. The lateral dorsal nucleus and the anterior nuclear group, including the anterior dorsal, anterior ventral, and anterior medial nuclei, are the major thalamic recipients of projections from limbic cortex. Corticothalamic projections also terminate sparsely in the midline and intralaminar nuclear complex, including the central lateral, central dorsal, paracentral, central medial, rhomboid, and reuniens nuclei. Projections from the anterior limbic area project predominantly to the anterior medial, centrall lateral, and paracentral nuclei. The anterior ventral nucleus, anterior medial nucleus, and lateral dorsal nucleus are the major thalamic recipients of projections from the cingular area, the granular and dysgranular retro-splenial areas, and the presubiculum. It appears that the anterior dorsal nucleus receives afferents only from the dysgranular retrosplenial area. Bilateral corticothalamic projections were found in the anterior medial, dorsal medial, central lateral, central medial, paracentral, and reuniens nuclei.
Role of catalysts in the surface synthesis of single-walled carbon nanotubes

We demonstrate the role of catalysts in the surface growth of single-walled carbon nanotubes (SWNTs) by reviewing recent progress in the surface synthesis of SWNTs. Three effects of catalysts on surface synthesis are studied: type of catalyst, the relationship between the size of catalyst particles and carbon feeding rates, and interactions between catalysts and substrates. Understanding of the role of catalysts will contribute to our ability to control the synthesis of SWNTs on various substrates and facilitate the fabrication of nanotube-based devices.
Adaptive hysteresis-band current controller

One of the most complicated control problems in variable speed AC drives is the difficulty of processing feedback signal of the outer loop in the presence of harmonics. However, conventional fixed band hysteresis controller has a variable switching frequency throughout the fundamental period. A variable-hysteresis-band controller comes as a solution to reach an optimal ripple current. An improved implementation of the constant frequency hysteresis current control of three phase voltage-source inverters is presented. A simple, self-adjusting analogue prediction of the hysteresis band is added to the phase-locked-loop control to ensure constant switching frequency, even at a high rate of output voltage change. This allows high accuracy in tracking highly distorted current waveforms and minimises the ripple in multiphase systems. In this paper, the basic principles are described, and a detailed stability analysis is done. The control performance is illustrated, both by simulated and experimental results.
Preemption of compliance costs and the voluntary adoption of SFAS No. 123(R)

Purpose – This paper aims to study a preemption proposition for the compliance costs associated with stock option expensing under SFAS 123(R) by examining whether early adopters used their discretion over option pricing model inputs to mitigate the adoption effect. Design/methodology/approach – The paper uses a matched sample approach of firms that voluntarily adopted stock option expensing during the 2002-2004 period and similar firms that waited until the mandatory expensing. The paper empirically examines some determinants of voluntary adoption, and the changes in option pricing model inputs during the period leading to mandatory expensing. Findings – The paper reports evidence that voluntary adopters of stock option expensing during the 2002-2004 period have used the period leading to mandatory expensing to preempt its compliance cost effect. The authors exercised their discretion by decreasing estimates for stock price volatility and time-to-maturity to preempt or minimize the reduction in earnings b...
Improving university facilities services using Lean Six Sigma: a case study

Purpose – The purpose of this paper is to present a case study on the use of Lean Six Sigma principles and tools to study the improvement in design and construction services at a university. The quality of facilities services at universities has been criticized by users calling for improvement. Design/methodology/approach – Quality of facilities services at universities has been criticized by users calling for improvement. The purpose of this paper is to present a case study on using Lean Six Sigma principles and tools to study improving design and construction services at a university. Findings – It was found that non-value-added general improvement review form (GIRF) process steps involving revisions and rework for the design and construction result in time delays, cost increases and quality deficiencies and render cost estimates unreliable; these are unnecessary and should be minimized or eliminated. It was additionally noted that administrative reviews and approvals embedded in GIRF processes slow dow...
PORTAL AND CUBITAL SERUM INSULIN DURING ORAL, PORTAL AND CUBITAL GLUCOSE TOLERANCE TESTS

Oral, intracubital, and intraportal glucose tolerance tests have been performed on 7 non-obese non-diabetics, and glucose and insulin concentrations have been followed in the peripheral and portal blood. A significant rise in portal glucose and insulin was found 1/2-2 min after oral glucose intake. There was no lag between the rise in insulin and glucose concentrations. The portal glucose concentration after oral glucose intake was significantly higher than after cubital glucose infusion for 45 min, although the peripheral glucose concentrations were identical. In the cubital vein the insulin concentration after oral glucose intake was significantly higher than after i.v. glucose infusion, but in the portal blood there was no difference. After portal glucose infusion the cubital insulin concentration did not differ significantly from the concentration after i.v. glucose infusion. Thus, it seems unlikely that a high portal glucose concentration is responsible for the higher peripheral insulin concentration after oral glucose intake. A high portal glucose concentration does not seem to influence the hepatic uptake or release of glucose.
Parent involvement in early intervention for disadvantaged children: Does it matter?

Abstract This study investigated the association between parent involvement in early intervention and children's later school competence. Parents ( N = 704) of children participating in the Chicago Longitudinal Study were interviewed retrospectively about their school involvement in preschool and kindergarten. Parents reported on the activities in which they participated and their frequency of program participation. Results indicated that even after controlling for family background, the number of activities in which parents participated in preschool and kindergarten was significantly associated with higher reading achievement, with lower rates of grade retention at age 14 (eighth grade), and with fewer years in special education. The frequency of parent involvement was only marginally associated with reading achievement but was associated with lower rates of grade retention and fewer years in special education. A confirmatory analysis indicated that teacher ratings of parent involvement in first and second grade were significantly associated with higher reading achievement in eighth grade, lower grade retention rates, and lower rates of special education placement through eighth grade. Findings support the benefits of parent involvement in early childhood programs.
Cognitive Demands and Second-Language Learners: A Framework for Analyzing Mathematics Instructional Contexts

The issues involved in teaching English language learners mathematics while they are learning English pose many challenges for mathematics teachers and highlight the need to focus on language-processing issues related to teaching mathematical content. Two realistic-type problems from high-stakes tests are used to illustrate the complex interactions between culture, language, and mathematical learning. The analyses focus on aspects of the problems that potentially increase cognitive demands for second-language learners. An analytical framework is presented that is designed to enable mathematics teachers to identify critical elements in problems and the learning environment that contribute to increased cognitive demands for students of English as a second language. The framework is proposed as a cycle of teacher reflection that would extend a constructivist model of teaching to include broader linguistic, cultural, and cognitive processing issues of mathematics teaching, as well as enable teachers to develo...
Numerical simulation of quasi-periodic solutions of the sine-Gordon equation

Abstract Analytic solutions of the sine-Gordon equation corresponding to periodic boundary conditions can be complicated, especially if initial values are chosen in the vicinity of homoclinic orbits. For such initial values it has been demonstrated that numerical solutions develop instabilities and may become chaotic. Because of the analytical complexities one cannot easily calculate the accuracy of the numerical solutions and therefore compare different numerical schemes in a straightforward manner. In this note we evaluate numerical methods in terms of the nonlinear spectrum. In particular, it provides one with a means of comparing symplectic and nonsymplectic integrators for integrable infinite dimensional Hamiltonian systems.
Developing a video game metadata schema for the Seattle Interactive Media Museum

As interest in video games increases, so does the need for intelligent access to them. However, traditional organizational systems and standards fall short. To fill this gap, we are collaborating with the Seattle Interactive Media Museum to develop a formal metadata schema for video games. In the paper, we describe how the schema was established from a user-centered design approach and introduce the core elements from our schema. We also discuss the challenges we encountered as we were conducting a domain analysis and cataloging real-world examples of video games. Inconsistent, vague, and subjective sources of information for title, genre, release date, feature, region, language, developer and publisher information confirm the importance of developing a standardized description model for video games.
PAMAM dendrimers on controlled pore glass: The effect of tethered dendrimer size and tethered affinity groups NTA and terpy on metal ion and indicator dye uptake

Abstract PAMAM dendrimer monolayers were covalently immobilized onto controlled pore glass (CPG) particles as platforms to graft the metal ion affinity groups nitrilotriacetic acid (NTA) and terpyridine (terpy). Functional end group analyses, metal ion loading capacities and indicator dye complexation to metal affinity sites were measured as a function of dendrimer size. Metal ions were efficiently extracted from 5 ppm solutions flowing through a packed column of modified CPG and loading capacities increased linearly with immobilized dendrimer size at pH 7.2 as determined by atomic absorption spectroscopy. The dendrimer tethered terpy affinity group was surprisingly effective in aqueous solution for extraction of Zn, Cu and Pb ions, but not as effective for Ni ions when compared to tethered NTA. Metal ion indicator dyes bind to the immobilized metal affinity sites showing a generational dependence. Subsequent addition of pyrophosphate releases dye back into solution as a demonstration of an immobilized indicator displacement assay.