cssi/SciSciGPT-SciSciNet huggingface dataset:
The determinants of the number of rooms occupied by compound dwellers in Kumasi, Ghana: does working at home mean more rooms?

Abstract This paper focuses on the number of rooms occupied by compound dwellers in Kumasi, Ghana, testing the hypothesis that households using their homes for income generation occupy more rooms. The study uses data collected from a 596-household survey in Kumasi in 1996. About a quarter of the sample households used their home for income generation. Using logistic regression to examine the determinants of number of rooms occupied by sample households showed that the use of housing for income generation is a statistically significant determinant of the number of rooms occupied by compound dwellers.
Tumor targeting of a cell penetrating peptide by fusing with a pH-sensitive histidine-glutamate co-oligopeptide

Cell penetrating peptides (CPPs) have been well established as potential carriers for intracellular delivery of protein/peptide therapeutics. However, their lack of selectivity impedes their application in vivo. In order to increase their specificity, a highly pH-sensitive histidine-glutamate (HE) co-oligopeptide was fused with a CPP, i.e. model amphipathic peptide (MAP), and was expressed as a fusion protein with glutathione S-transferase (GST) acting as a cargo protein. Compared with two other fusion proteins containing either HE or MAP, only the fused peptide (HE-MAP) could effectively deliver the cargo GST protein to cells at pH 6.5 or below, while maintaining low delivery to cells at pH 7.0 and above. Using a xenograft mouse model of human breast cancer, fluorescent imaging showed that only HE-MAP could effectively target GST to the tumor site, while reducing non-specific association of MAP in other organs. The data presented in this report demonstrate the diagnostic and/or therapeutic potential of the fused peptide, HE-MAP, for targeting the acidic tumor microenvironment. The concise design for this pH-sensitive peptide offers a simple way to overcome CPP's lack of selectivity, which could lead to increased application of CPPs and macromolecular therapeutics.
Color Displays And The Color Deficient Operator

The increased use of multi-color displays in C31 applications has raised the question of color deficient operators. By screening operators who are involved in critical color discriminations and by the proper design and testing of the developed product, this concern can be eliminated.
Lasers in general surgery

Laser technology has wide application in general surgery. The CO2 laser functions as a scalpel sealing small blood vessels in the process of dividing tissues. The YAG laser has been especially useful in the performance of liver resection and the coagulation of large vascular tumors. The utility of lasers in various types of general surgical procedures is discussed.
Pediatric rheumatic disease: Vaccination in pediatric rheumatic disease--risks and benefits.

In an age in which immunosuppression is the standard of care for many pediatric rheumatic diseases, balancing the risks and benefits of vaccinations is forefront. Three main issues—addressed in new guidelines—surround vaccination practices in these patients: safety, immunogenicity and effects of the vaccine on the underlying rheumatic disease.
On hobbits and the growth of APL

When J. R. R. Tolkien was in the process of writing The Lord of the Rings, the unfolding of the take was apparently as much a process of discovery as of definition or creation. That is, as each part of the tale unfolded, it has to "fit" with the rest of what was known and felt about Middle Earth and its inhabitants. While an elaboration or extension would open up new vistas for the author and his readers, it could not be put down unless it had a sense of rightness, and a "ring of truth". The books are characterized by integrity, courtesy, a sure sense of what will bring pleasure to readers, and a sense of what will motivate them to read further, as well as bring them back for second and third readings. These values have captured the imagination of millions of readers, young and old. Not only do these enthusiasts buy books and records for themselves, they proselytize others.
Optimized Germanium co-implant with B2H6 PLAD for better advanced PMOS device performance

This work demonstrates that the sequence of a Ge co-implant with a B 2 H 6 PLAD in the source/drain is very critical in order to improve advanced PMOS performance. Locating the Ge co-implant after the B 2 H 6 PLAD resulted in higher total retained B dose and less implant damage. PMOS performance was significantly improved compared to B 2 H 6 PLAD without the Ge co-implant or Ge co-implant before B 2 H 6 PLAD. The Ge implant energy was optimized to locate the Ge peak around the B deposition layer/Si substrate interface for a better knocking effect and less implant damage. With the optimized Ge implant conditions the source/drain contact resistance and sheet resistance were significantly reduced, while the junction leakage current was not degraded. As a result, PMOS I ds improved by 12%, transconductance KL improved by 14%, and I OFF variation improved by 33% without significant change in mean I OFF . This process helps overcome technical challenges of B 2 H 6 PLAD, providing a path for continued scaling of PMOS junction depth with improved device performance.
The feasibility of large refracting telescopes for solar coronal research

Measuring magnetic fields in the solar corona requires a large aperture telescope with exceptionally low levels of scattered light. For internally-occulted coronagraphs the main source is scattering from dust or microroughness on the primary lens or mirror. We show refracting primaries offer significantly lower levels for both sources. To observe magnetic fields in the solar corona with scientifically interesting spatial and temporal resolutions, a 1 meter aperture or larger is required. For a long time such large-scale refractors have been deemed impractical or impossible to construct due to gravitational deformation of the lens. We present the results of finite-element and optical analyses of the gravitational deformation, stress-induced birefringence, and absorptive heating of a (see manuscript)1.5 meter f/5 fused silica lens. These studies demonstrate the traditional objections to large refractors are unfounded and large refracting primaries have unique capabilities.
Performance of emergency physicians utilizing a video-assisted semi-rigid fiberoptic stylet for intubation of a difficult airway in a high-fidelity simulated patient: a pilot study

This study was designed to evaluate emergency physician success and satisfaction using a video-assisted semi-rigid fiberoptic stylet, the Clarus Video System (CVS), during a simulated difficult airway scenario. Emergency physicians (EPs) of all levels were first shown a brief slide show and three example videos, and then given 20 min to practice intubating a mannequin using both the CVS and standard direct laryngoscopy (DL). The mannequin was then placed in a c-collar and set to simulate an apneic patient with an edematous tongue and trismus. Each EP was given up to three timed attempts with each technique. They rated their satisfaction with the CVS, usefulness for their practice, and the effectiveness of the tutorial. Direct laryngoscopy had a 65% success rate on the first attempt, 20% on the second, and 15% required three or more. The CVS had a 100% success rate with a single attempt. Average time for independent DL attempts was 43.41 s (SD = ±26.82) and 38.71 s (SD = ±34.14) with CVS. Cumulative attempt times were analyzed and compared (DL = 74.55 ± 68.40 s and CVS = 38.71 ± 34.14 s; p = 0.028). EPs rated their satisfaction with, and usefulness of, the CVS as ≥6 out of 10. Emergency physicians were able to successfully intubate a simulated difficult airway model on the first attempt 100% of the time. Emergency physicians were satisfied with the CVS and felt that it would be useful in their practice.
Dynamic techniques for yield enhancement of field programmable logic arrays

Two techniques are presented to increase the effective yield of field programmable logic arrays (FPLAs). In the first technique, a reconfiguration scheme is proposed to dynamically alter the product-term allocation of the mask PLA onto the product lines of the raw FPLA once a type-two fault is diagnosed. This technique does not require any extra product lines to obtain a usable destination FPLA. The second technique utilizes the often unused product lines within the FPLA. It is shown that once an error is detected during the programming procedure, a product line can always be desensitized from the rest of the FPLA. The intended product term is then simply reprogrammed onto one of the extra product lines. >
Bilateral pyosalpinx in a peripubescent female with Hirschsprung's disease: a case report

This is a case report of bilateral pyosalpinx in a peripubescent female with a history of Hirschsprung's disease. Bilateral pyosalpinx is a rare condition in non-sexually active females. The presence of this disease in a patient with a history of Hirschsprung's disease is concerning for an association of the two processes.
Urinary Excretion of 3-Hydroxyisovaleryl Carnitine Is an Early and Sensitive Indicator of Marginal Biotin Deficiency in Humans

Mounting evidence indicates that marginal biotin deficiency is not rare, contrary to previous assumptions. Accordingly, robust indicators of biotin status would be useful. In a study of 10 healthy adults, we recently provided evidence that abnormally increased plasma concentration of 3-hydroxyisovaleryl carnitine (3HIA-carnitine) is a sensitive indicator of marginal biotin deficiency. We sought to determine whether urinary excretion of 3HIA-carnitine (expressed as the ratio to urinary creatinine) significantly increases in marginal biotin deficiency. Marginal, asymptomatic biotin deficiency was induced experimentally in the same 10 healthy adults (8 women) by feeding undenatured egg white with meals for 28 d. Biotin status was repleted by a mixed general diet plus biotin supplementation. Urinary excretion of 3HIA-carnitine was determined by liquid chromatography-tandem MS on d 0, 14, and 28 (depletion) and on d 35 and 50 (repletion). Mean urinary 3HIA-carnitine concentration increased with depletion (P < 0.0001; d 0 vs. 28) and decreased with repletion (P = 0.0002; d 28 vs. 50). Urinary 3HIA-carnitine excretion was greater than the upper limit of normal in 9 of 10 participants by d 14 and decreased to within normal limits by d 50 in all participants. This study provides evidence that urinary excretion of 3HIA-carnitine is an early and sensitive indicator of marginal biotin deficiency. The ease of collection of untimed urine samples and application of a new analytical method with simplified sample preparation suggest that urinary 3HIA-carnitine is likely to be a useful indicator for large population studies.
Does alleviating poverty affect mothers’ depressive symptoms? A quasi-experimental investigation of Mexico’s Oportunidades programme

Background Depression is a major cause of disability, particularly among women; poverty heightens the risk for depression. Beyond its direct effects, maternal depression can harm children’s health and development. This study aimed to assess the effects of a large-scale anti-poverty programme in Mexico (Oportunidades) on maternal depressive symptoms. Methods In 2003, 5050 women living in rural communities who had participated in Oportunidades since its inception were assessed and compared with a group of 1293 women from matched communities, whose families had received no exposure to Oportunidades at the time of assessment but were later enrolled. Self-reported depressive symptoms were measured using the Center for Epidemiologic Studies Depression Scale (CES-D). Ordinary least squares regressions were used to evaluate the treatment effect of programme participation on depression while adjusting for covariates and clustering at the community level. Results Women in the treatment group had lower depressive symptoms than those in the comparison group (unadjusted mean CES-D scores: 16.9 ± 9.8 vs 18.6 ± 10.2). In multivariable analyses, programme participation was associated with lower depression whilst controlling for maternal age, education and household demographic, ethnicity and socio-economic variables [β = −1.7 points, 95% confidence interval (95% CI) −2.46 to −0.96, P < 0.001]. Reductions in perceived stress and increases in perceived control were mediators of programme effects on women. Conclusions Although Oportunidades did not target maternal mental health directly, we found modest but clinically meaningful effects on depressive symptoms. Our design permits stronger causal inference than observational studies that have linked poverty and depressive symptoms. Our results emphasize that the well-being of individuals is responsive to macro-level economic policies and programmes.
The Intervening Hand: Contemporary International Expansion Processes of the Regional Bell Operating Companies

A case study method was used to investigate the regional Bell operating companies (RBOCs) and to develop an inductive model based on their international expansion processes. The model consists of three phases, with two abrupt turning points during the companies' first 8 years of international expansion. The turning points are the result of deliberate top management interventions that provided forward thrust from one phase to the next. Those interventions highlight the role of strategic choice, which had been lacking in previous international expansion models. Given the prominent role of strategic choice, the authors link the international expansion model to the strategy-making process literature and address the larger issue of how new strategic directions are formed within organizations facing industry deregulation.
Use of fertility treatment modalities in a large United States cohort of professional women

Objective To evaluate the use of fertility treatments among a large cohort of women in the United States. Design Cohort study. Setting Nurses' Health Study II. Patient(s) Ten thousand thirty-six women who reported having used fertility treatment on biennial questionnaires from 1993–2009. Intervention(s) None. Main Outcome Measure(s) Data on patterns of treatment modality were collected via self-report from validated mailed questionnaires. Information on clomiphene, gonadotropin injections alone, and gonadotropin injections as part of intrauterine insemination (IUI) and in vitro fertilization (IVF) was queried. Result(s) Most women who reported fertility treatment used clomiphene (94%), with a large majority reporting clomiphene as their only form of treatment (73%). Of women who reported treatment more advanced than clomiphene, 13% had used gonadotropin injections alone, 11% IUI treatment, and 11% IVF. Several subgroups were more likely to use multiple treatment modalities and to initiate treatment with gonadotropins rather than clomiphene, including women living in states with insurance coverage of fertility procedures, with higher household income, younger in age, who remained nulliparous at the study close, and treated after 2000. Conclusion(s) Results should be interpreted cautiously, but to our knowledge, this represents the first study of fertility treatment patterns in the United States and could inform public health planning.
Redescription and first records from Brazil of Diacyclops uruguayensis Kiefer (Crustacea, Copepoda, Cyclopidae)

Diacyclops uruguayensis Kiefer, 1935 is redescribed from specimens from Santa Catarina and Ceara, Brazil. These new records represent a significant range extension from southern Uruguay.
B 74-30 Foundation of the Theory of Learning Systems

One important area in engineering cybernetics is that of learning systems—the analysis and synthesis of engineering systems which exhibit learning behavior. During the past decade there has been a considerable growth of research interest in problems of learning systems. Many different approaches have been proposed for the design of systems with learning capabilities. Engineering applications include pattern recognition, communication and antenna systems, and control and diagnostic problems. Recent progress has indicated that the research in learning systems has just gone through a transient period from discussions of general philosophy, concepts and formulations of the problem to studies of a possible unified theory. This progress is significant in the sense that, once a unified approach is successful, further research efforts can then be concentrated toward the depth of the theory and its applications. One of the major contributors in this direction is Prof. Tsypkin, the author of this book. Under a general approach of probabilistic iterative algorithms or stochastic approximation procedures, this book treats systematically a broad class of problems in learning systems. Many existing learning algorithms can be put under this same general formulation, and these are compared.
Pharmaceutical nanocarrier association with chondrocytes and cartilage explants: influence of surface modification and extracellular matrix depletion

Summary Objective To evaluate cartilage diffusion and isolated chondrocyte association of micelles and liposomes and to determine the effect of cell-penetrating peptide (CPP) surface functionalization and extracellular matrix depletion on chondrocyte association and cartilage diffusion, respectively. Methods Rhodamine-labeled micelles and liposomes were incubated with bovine chondrocytes and cell-associated fluorescence was quantified using flow cytometry. Rhodamine-labeled CPP-modified micelles and liposomes were incubated with chondrocytes and cell-associated fluorescence was compared to unmodified nanocarriers. Rhodamine-labeled micelles and liposomes were incubated with bovine cartilage explants for 1, 2 and 4 h and cartilage-associated fluorescence was compared across groups. Cartilage explants were treated with interleukin-1 alpha (IL-1α) or with 0.25% trypsin. Rhodamine-labeled micelles and liposomes were incubated with control, IL-1 and trypsin-treated explants and cartilage-associated fluorescence was compared across groups. Results Chondrocyte-associated fluorescence following treatment with micelles was significantly higher ( P P P Conclusion Micelles exhibit superior association with isolated chondrocytes compared to liposomes. Surface modification with a CPP enhances chondrocyte association of both nanocarriers. 15 nm diameter micelles are better than 138 nm diameter liposomes in penetrating articular cartilage and extracellular matrix depletion enhances micelle penetration.
HEAT‐INDUCED OFF‐FLAVOR IN AVOCADO FLESH

SUMMARY— The off-flavor induced in the Fuerte avocado by heating at 100°C for 20 min has been examined. Isolates which exhibited off-flavor were obtained by ethanol extraction of freeze-dried avocado puree. The ether-soluble portion of these extracts was separated by silicic acid column chromatography and thin-layer chromatography. The presence of off-taste in individual fractions was determined by a quantitative taste assay using ethanol-extracted pulp or filter paper as taste medium. Fraction II from a silicic acid column possessed the most dominant off-taste and represented 0.6% of the original avocado flesh. It was a mixture which varied in polarity between that of neutral lipid and phospholipid. Separation of Fraction II by TLC showed the presence of at least 12 components. Separation of the analogous fraction from unheated control samples showed the presence of the same components in similar amounts. Only pheophytins a and b, which were formed by heating, ware missing from the control. Attempts to isolate further by TLC and to characterize substances responsible for off-taste resulted in a significant reduction in off-taste intensity of heat-treated isolates as well as the appearance of similar off-taste in the analogous control. The attenuation is partially accounted for by a synergistic effect involving separated zones from the chromatogram. The over-all off-flavor involved most isolates, though substances responsible were present in quantities undetected by chromatographic techniques
Sideroblastic anemia secondary to zinc toxicity.

![Figure][1] A 52-year-old African-American woman with a history of allergic rhinitis and alcohol abuse presented with a presyncope. The following levels were found: hemoglobin, 3.7 g/dL; mean cell volume, 82 fL; white blood cell count, 9.2 × 103/μL; and platelets, 168 × 103/μL. The
Electrical impedance imaging with electrode models: initial in vivo experience in the breast

Electrical impedance imaging of the breast is potentially promising but faces a number of challenges related to improving the sensitivity and reliability of the technique. Electrode models have been accepted as important components of image reconstruction but little practical experience with their use during image reconstruction from in vivo data has been reported. In this paper, we describe our approach to electrode modeling and present representative image reconstructions of in vivo breast exams with and without the use of an electrode model. Incorporation of an electrode model is found to improve image quality, especially in terms of reducing near-surface artifacts and improving the sensitivity of the conductivity image component image; however, the effects are generally secondary to the dominant image trends that appear with or without the use of an electrode model.
Activation of Translation in Pituitary Gonadotrope Cells by Gonadotropin-Releasing Hormone

The neuropeptide GnRH is a central regulator of mammalian reproductive function produced by a dispersed population of hypothalamic neurosecretory neurons. The principal action of GnRH is to regulate release of the gonadotropins, LH and FSH, by the gonadotrope cells of the anterior pituitary. Using a cultured cell model of mouse pituitary gonadotrope cells, aT3‐1 cells, we present evidence that GnRH stimulation of aT3‐1 cells results in an increase in cap-dependent mRNA translation. GnRH receptor activation results in increased protein synthesis through a regulator of mRNA translation initiation, eukaryotic translation initiation factor 4E-binding protein, known as 4EBP or PHAS (protein, heat, and acid stable). Although the GnRH receptor is a member of the rhodopsin-like family of G protein-linked receptors, we show that activation of translation proceeds through a signaling pathway previously described for receptor tyrosine kinases. Stimulation of translation by GnRH is protein kinase C and Ras dependent and sensitive to rapamycin. Furthermore, GnRH may also regulate the cell cycle in aT3‐1 cells. The activation of a signaling pathway that regulates both protein synthesis and cell cycle suggests that GnRH may have a significant role in the maintenance of the pituitary gonadotrope population in addition to directing the release of gonadotropins. (Molecular Endocrinology 14: 1811‐1819, 2000)
Quadratic‐spline collocation methods for two‐point boundary value problems

A new collocation method based on quadratic splines is presented for second order two-point boundary value problems. First, O(h4) approximations to the first and second derivative of a function are derived using a quadratic-spline interpolant of u. Then these approximations are used to define an O(h4) perturbation of the given boundary value problem. Second, the perturbed problem is used to define a collocation approximation at interval midpoints for which an optimal O(h3-J) global estimate for the jth derivative of the error is derived. Further, O(h4-J) error bounds for the jth derivative are obtained for certain superconvergence points. It should be observed that standard collocation at midpoints gives O(h2-J) bounds. Results from numerical experiments are reported that verify the theoretical behaviour of the method.
A New Type of Single-phase Motor

This paper deals with the development of a constant speed a-c. motor for application to single-phase current. A description is given of the derivation of this new type of motor from the plain repulsion motor. The novel feature lies in the armature which consists of a combination of three elements, namely: a commutated winding, a squirrel cage of high reactance, and a commutating device consisting of shielding metal strips. It is shown that this motor in starting and acceleration possesses the characteristics of a series motor and when up to speed has the characteristics of a shunt motor. The changing over from the series to the shunt type is accomplished without the use of any automatic device, this change taking place due to the inherent qualities of the motor. An explanation is given of the high power-factor possessed by this motor and also an elementary theory of commutation, which has proved to be as good as that in a d-c. motor with commutating poles.
Toward a Functional Catalog of the Plant Genome. A Survey of Genes for Lipid Biosynthesis

Public databases now include vast amounts of recently acquired DNA sequences that are only partially annotated and, furthermore, are often annotated by automated methods that are subject to errors. Maximum information value of these databases can be derived only by further detailed analyses that frequently require careful examination of records in the context of biological functions. In this study we present an example of such an analysis focused on plant glycerolipid synthesis. Public databases were searched for sequences corresponding to 65 plant polypeptides involved in lipid metabolism. Comprehensive search results and analysis of genes, cDNAs and expressed sequence tags (ESTs) are available online (http://www.canr.msu.edu/lgc). Multiple alignments provided a method to estimate the number of genes in gene families. Further analysis of sequences allowed us to tentatively identify several previously undescribed genes in Arabidopsis. For example, two genomic sequences were identified as candidates for the palmitate-specific monogalactosyldiacylglycerol desaturase (FAD5). A candidate genomic sequence for 3-ketoacyl-acyl-carrier protein (ACP) synthase involved in mitochondrial fatty acid biosynthesis was also identified. Biotin carboxyl carrier protein (BCCP) in Arabidopsis is encoded by at least two genes, but the most abundant BCCP transcript so far has not been characterized. The large number (>165,000) of plant ESTs also provides an opportunity to perform “digital northern” comparisons of gene expression levels across many genes. EST abundance in general correlated with biochemical and flux characteristics of the enzymes in Arabidopsis leaf tissue. In a few cases, statistically significant differences in EST abundance levels were observed for enzymes that catalyze similar reactions in fatty acid metabolism. For example, ESTs for the FatB acyl-ACP thioesterase occur 21 times compared with 7 times for FatA acyl-ACP thioesterase, although flux through the FatA reaction is several times higher than through FatB. Such comparisons may provide initial clues toward previously undescribed regulatory phenomena. The abundance of ESTs for ACP compared with that of stearoyl-ACP desaturase and FatB acyl-ACP thioesterase suggests that concentrations of some enzymes of fatty acid synthesis may be higher than their acyl-ACP substrates.
Does Amount and Type of Activity Matter in Behavioral Activation? A Preliminary Investigation of the Relationship between Pleasant, Functional, and Social Activities and Outcome.

Background Accumulating evidence supports behavioral activation (BA) as an effective stand-alone treatment for improving depression and related conditions, though little is known about the factors that influence positive outcomes. Such research is ripe for future dissemination and implementation efforts, particularly among vulnerable older adult populations in need of such efficacious and transportable treatments. Aims Given the central but largely unexamined role that increasing activities plays in BA, we investigated the association between participation in weekly activities and treatment outcome. Method As a preliminary study of this research question, we report on a sample of 20 older adults with symptoms of depression and complicated bereavement who completed 5 weeks of BA, pre- and posttreatment measures, and weekly planners of BA activities. All activities were coded as either functional or pleasurable (by participants) and if they were social in nature (by trained coders). Results Overall, BA was associated with reductions in symptomatology. However, participants' total number of reported activities, and their relative proportion of functional, pleasurable, and social activities, did not significantly relate to their improvement in symptoms. Conclusion One interpretation of the findings suggests that countering avoidance more generally, potentially independent of the specific type or total amount of activation activities, may be associated with amelioration of symptomatology.
Coastal Mapping Handbook

A description is given of the Coastal Mapping Handbook distributed by the Government Printing Office. The handbook contains a complete but elementary description of the mapping process and includes examples of map products. Names and addresses of state and federal sources of technical assistance are also included in the handbook.
Focus on . . . The Social Security and Medicare Trustees' Reports

This article discusses the reports issued in May 2006 by the Social Security and Medicare Trustees.
Origins of Formal Structure

Mathematics, at the beginning, is sometimes described as the science of Number and Space—better, of Number, Time, Space, and Motion. The need for such a science arises with the most primitive human activities. These activities presently involve counting, timing, measuring, and moving, using numbers, intervals, distances, and shapes. Facts about these operations and ideas are gradually assembled, calculations are made, until finally there develops an extensive body of knowledge, based on a few central ideas and providing formal rules for calculation. Eventually this body of knowledge is organized by a formal system of concepts, axioms, definitions, and proofs. Thus Euclid provided an axiomatization of geometry, with careful demonstrations of the theorems from the axioms; this axiomatization was perfected by Hilbert about 1900, as we will indicate in Chapter III. Similarly the natural numbers arise from counting, with notation which provides to every number the next one—its successor, and with formal rules for calculating sums and products of numbers. It then turns out that all these formal rules can be deduced from a short list of axioms (Peano-Dedekind) on the successor function (Chapter II). Finally, the measurements of time and space eventually are codified in the axioms (Chapter IV) for the real numbers.
Using the Cognitive Pretesting Method to Gain Insight Into Participants’ Experiences: An Illustration and Methodological Reflection

Quantitative researchers traditionally use cognitive pretesting methods such as think-alouds to determine whether participants are interpreting close-ended survey items as intended. I applied this ...
Magic Squares, Finite Planes, and Points of Inflection on Elliptic Curves

Ezra (Bud) Brown (brown@math.vt.edu) has degrees from Rice and Louisiana State, and has been at Virginia Tech since the first Nixon Administration. His research interests include graph theory, the combinatorics of finite sets, and number theory?especially elliptic curves. In 1999, he received the MAA MD-DC-VA Section Award for Outstanding Teaching, and he loves to talk about mathematics and its history to anyone, especially students.
The Influence of Functionals on Density Functional Theory Calculations of the Properties of Reducible Transition Metal Oxide Catalysts

Reducible transition metal oxides (RTMOs) comprise an important class of catalytic materials that are used for the selective oxidation and electro- and photochemical splitting of water, and as supports for metal nanoparticles. It is, therefore, highly desirable to model the properties of these materials accurately using density functional theory (DFT) in order to understand how oxide structure and performance are related and to guide the search for materials exhibiting superior performance. Unfortunately, accurate description of the structural and electronic properties of RTMOs using DFT has proven particularly challenging. The M06-L density functional, which has been shown to be broadly accurate for calculations of gas phase clusters, has recently become available to researchers carrying out calculations in the solid state, but its performance in determining the properties RTMOs has been little investigated. The aim of this work was to assess the performance of the M06-L functional for describing the str...
Exploring the Relationship Between Deaf Identity Verification Processes and Self-Esteem

ABSTRACTPast research has found that self-esteem in deaf individuals is predicted by variables such as the age they become deaf, the type of school they attend, whether they use sign language or another mode of communication, their parents’ hearing status, and their family’s socioeconomic status. This study applies identity control theory and examines the relationship between Deaf identity verification processes and self-esteem. The results show that, when controlling for variables known to relate to self-esteem, deaf individuals’ education and the degree of difficulty they have in verifying self-meanings in social situations are the only significant predictors of variance in self-esteem. The article discusses the study findings and considers the implications for identity control theorists and Deaf studies scholars.
Nuclear localization of porcine reproductive and respiratory syndrome virus nonstructural protein 4

To demonstrate the function of porcine reproductive and respiratory syndrome virus(PRRSV)nonstructural protein 4(NSP4),the recombinant pEGFP-N1-nsp4 was constructed and transfected into Marc-145 cells.The localization of the NSP4 protein fused to an enhanced green fluorescent protein(NSP4-EGFP)was studied in Marc-145 cells using GFP protein as biomarker.Furthermore recombinant plasmids containing partial deleted or truncated portion of the nsp4 gene were designed according to the hydrophobicity of the NSP4 protein and transfected into Marc-145 in order to determine the region responsible for nuclear localization of the NSP4.The results showed that NSP4-EGFP was predominantly localized in cell nucleus.A hinge region(HR)was responsible for nuclear localization of NSP4 protein.The results suggested that NSP4 nuclear localization is an active import process,with that NSP4 may interact with a cellular protein through the HR region and be shuttled into nucleus.
Calcium influx in platelet activating factor-induced atrial natriuretic peptide release in rat cardiomyocytes.

Atrial natriuretic peptide (ANP) is released from the myocardium after the activation of protein kinase C and/or ischemia, events that are associated with an increase in platelet activating factor (PAF) production in this tissue. In this study we demonstrate that PAF, but not lyso-PAF, induces a concentration-dependent increase in ANP secretion in spontaneously beating neonatal rat cardiomyocytes, a response associated with increases in cellular adenosine 3',5'-cyclic monophosphate (cAMP) formation, calcium influx, and the mobilization of calcium from intracellular stores. cAMP formation and calcium influx appear to play major roles in PAF-induced ANP secretion in this system, insofar as PAF-induced ANP release was substantially reduced in the presence of the (R)-p-diastereoisomer of adenosine 3',5'-cyclic monophosphorothioate (10 microM), whereas both PAF-induced calcium influx and ANP secretion were abolished in the presence of the calcium channel antagonist nifedipine (0.1 microM). Consistent with thes...
A Gauss–Seidel type solver for the fast computation of input-constrained control systems

Abstract An important class of nonlinear control systems can be represented as the feedback interconnection of two parts: a linear time-invariant system and a block of decentralized nonlinearities. When the linear time-invariant part has a nontrivial feedthrough term or the nonlinearity has a feedback gain, control computation involves the online implementation of a multivariable algebraic loop which must be resolved at each sampling instant. The requirements for such online computation may result in several implementation issues, especially in real-time and embedded control applications. This paper considers the implementation of such algebraic loops arising from several input-constrained systems. The proposed solution algorithm is globally convergent for a very large class of feedthrough or feedback gains and shows promise for real-time and embedded control applications where a fast but approximate solution is of the essence.
Calculation Of Waiting Times For A Dynamic Token Passing Bus

Waiting times have been calculated for an explicit token passing LAN using a dynamic logical ring and a media access protocol which allows each station to transmit only one information packet during a token holding time. Additional delays associated with the maintenance of the dynamic ring as well as the ring entrance delays are included in the calculations of the waiting times. It is shown that the waiting time equation is controlled by the token rotation time. Because of the inherently convoluting properties of the logical ring, the token rotation time is approximately independent of the distribution of the packet lengths.
Finding the best ridge regression subset by genetic algorithms: applications to multilocus quantitative trait mapping

Genetic algorithms (GAs) are increasingly used in large and complex optimization problems. Here we use GAs to optimize fitness functions related to ridge regression, which is a classical statistical procedure for dealing with a large number of features in a multivariable, linear regression setting. The algorithm avoids overfitting, gracefully handles collinearity, and leads to easily interpretable results. We use the method to model the relationship between a quantitative trait and genetic markers in a mouse cross involving 69 F2 mice. The approach will be useful in the context of many genomic data sets where the number of features far exceeds the number of observations and where features can be highly correlated.
Entrepreneurial spawning and knowledge-based perspective: a meta-analysis

Entrepreneurial spawning is the transitory process by which employees of an existing firm leave their employment to initiate a new business venture. There is a lack of consensus regarding the predictors of entrepreneurial spawning. We used meta-analysis to analyze 28 studies (with 128 effect sizes) to examine the predictors of entrepreneurial spawning. Based on knowledge-based perspective, we hypothesize that employee characteristics (age, education, and job position) and parent firm characteristics (firm age, firm performance, and firm diversity) are significantly related to entrepreneurial spawning. We identified two inverted U-shaped relationships (age and tenure with entrepreneurial spawning) based on our meta-analytic hierarchical multiple regression analyses. Based on labor market rigidity perspectives, we also examined how country region (North America versus Europe) moderates the relationships between employee characteristics and entrepreneurial spawning and between parent firm characteristics and entrepreneurial spawning. Our paper provides theoretical and practical implications.
The emerging contribution of social wasps to grape rot disease ecology

Grape sour (bunch) rot is a polymicrobial disease of vineyards that causes millions of dollars in lost revenue per year due to decreased quality of grapes and resultant wine. The disease is associated with damaged berries infected with a community of acetic acid bacteria, yeasts, and filamentous fungi that results in rotting berries with high amounts of undesirable volatile acidity. Many insect species cause the initial grape berry damage that can lead to this disease, but most studies have focused on the role of fruit flies in facilitating symptoms and vectoring the microorganisms of this disease complex. Like fruit flies, social wasps are abundant in vineyards where they feed on ripe berries and cause significant damage, while also dispersing yeasts involved in wine fermentation. Despite this, their possible role in disease facilitation and dispersal of grape rots has not been explored. We tested the hypothesis that the paper wasp Polistes dominulus could facilitate grape sour rot in the absence of other insect vectors. Using marker gene sequencing we characterized the bacterial and fungal community of wild-caught adults. We used a sterilized foraging arena to determine if these wasps transfer viable microorganisms when foraging. We then tested if wasps harboring their native microbial community, or those inoculated with sour rot, had an effect on grape sour rot incidence and severity using a laboratory foraging arena. We found that all wasps harbor some portion of the sour rot microbial community and that they have the ability to transfer viable microorganisms when foraging. Foraging by inoculated and uninoculated wasps led to an increase in berry rot disease symptom severity and incidence. Our results indicate that paper wasps can facilitate sour rot diseases in the absence of other vectors and that the mechanism of this facilitation may include both increasing host susceptibility and transmitting these microbial communities to the grapes. Social wasps are understudied but relevant players in the sour rot ecology of vineyards.
Cow urine, Indian yellow, and art forgeries: An update

Abstract In a recent technical note in this Journal, de Faria et al., 2017 [1] reported the Raman spectrum of authentic Indian yellow artists’ pigment, correcting a decades old reference spectrum that has led to the misidentification of this pigment in artworks that actually contained tartrazine yellow. The present communication provides additional information and corrects important experimental details mentioned by de Faria et al. that should lead to further identifications of the authentic pigment in artworks. Despite their claim that the analysis of this naturally fluorescent colorant is only possible with Fourier transform (FT) instruments, the ready characterization of two authentic samples of historic Indian yellow pigment is demonstrated here using commonly available visible and near-infrared excitation sources on a dispersive Raman microspectrometer. To highlight the importance of the proper identification of dyes and colorants, the authentication and art historical implications of previous literature reports that have misidentified Indian yellow on historic documents are more thoroughly discussed here from a forensic science point of view. The numerous modern pigments that are sold as imitation Indian yellow are addressed and analyzed, allowing the ready noninvasive detection of anachronistic colorants in attempted forgeries. Finally, this unusual pigment is positively identified for the first time using non-invasive dispersive Raman microspectroscopy on a historic object of uncertain date, a highly decorative manuscript from the Indian subcontinent.
African-American Landscapes

This chapter largely deals with the contributions of enslaved Africans in building the American landscape—particularly in the Southern states, where the rural African-American population remains concentrated. It notes that Africans significantly contributed to the cultural landscape within the American South, including the introduction of certain crops from Africa. Many slaves and free persons of color came by way of various lands in the West Indies, resulting in distinct West Indian and Creole styles of architecture, particularly conspicuous in coastal cities along the Gulf of Mexico and the southern Atlantic. The African heritage shotgun house had similar origins and dispersed up the Mississippi and Ohio River Valleys. The post World War II development of African-American ghettos in Northern cities is described, resulting in several major cities having African-American majority populations. Development of middle class Black business districts and neighborhoods, such as Atlanta’s Auburn Avenue, have shaped Southern cities. Recent developments of African-American settlements within the former plantation South are also reviewed. This chapter also notes the recent patterns of immigration of blacks into the United States, both directly from Africa (many of whom are refugees) and from the West Indies, and it describes how their cultural landscapes may reshape our definition of what comprises an African-American.
Cigarette smoking quit rates among adults with and without alcohol use disorders and heavy alcohol use, 2002-2015: A representative sample of the United States population.

Background While the overall smoking quit rate has increased over time, it is not known whether the quit rate has also increased among persons with alcohol use disorders (AUDs) or heavy alcohol use (HAU). The current study examined quit rates among adults with and without AUDs and HAU over a 12-year period in a representative sample of US adults.
Response at Genetic, Metabolic, and Physiological Levels of Maize (Zea mays) Exposed to a Cu(OH)2 Nanopesticide

Nanopesticides are becoming more popular in modern agriculture to improve crop protection product efficacy. However, information on their implications for crop plants is needed. In this study, 3-week-old maize plants were exposed to different doses of Cu(OH)2 nanopesticide (0, 10, and 100 mg) for 7 days via foliar application. Gene expression of 9 antioxidant-related enzymes (CAT1, POD1, GST1, SOD-1A, SOD-B, GPX, APX1, HSP1, PER1) was determined using a quantitative real-time polymerase chain reaction. Using gas chromatography time-of-flight mass spectrometry, levels of 12 low-molecular-weight antioxidant compounds were measured. Results showed that a dose of 100 mg of Cu(OH)2 nanopesticide significantly decreased leaf chlorophyll content and biomass by 17–20%. In addition, potassium and phosphorus were up-regulated (14% and 13%, respectively) in response to this dose. Gene expression of POD1 and GST1 was significantly (p < 0.05) increased by 42.6% and 71.8%, respectively, at a dose of 10 mg, but declined...
Decreased Probability of Error in Template-Matching Classification Using Aspect-Diverse Bistatic SAR

We extend the concept of monostatic aspect diversity for improved automatic target recognition (ATR) to a bistatic synthetic aperture radar (SAR) platform. We derive the probability of error with respect to the number of aspects used for a simple two-target template-matching classification system. The validity of the error prediction is confirmed using simulated bistatic SAR images. Our results demonstrate the ATR benefits of supplementing monostatic SAR images with one or more bistatic SAR images.
Firing Rate Models

One of the most common ways to model large networks of neurons is to use a simplification called a firing rate model. Rather than track the spiking of every neuron, instead one tracks the averaged behavior of the spike rates of groups of neurons within the circuit. These models are also called population models since they can represent whole populations of neurons rather than single cells. In this book, we will call them rate models although their physical meaning may not be the actual firing rate of a neuron. In general, there will be some invertible relationship between the firing rate of the neuron and the variable at hand. We derive the individual model equation in several different ways, some of the derivations are rigorous and are directly related to some biophysical model and other derivations are ad hoc. After deriving the rate models, we apply them to a number of interesting phenomena, including working memory, hallucinations, binocular rivalry, optical illusions, and traveling waves. We also describe a number of theorems about asymptotic states as well as some of the now classical work on attractor networks.