cssi/SciSciGPT-SciSciNet huggingface dataset:
The relationship of dietary calcium to the maintenance of skeletal integrity in man—an interface of endocrinology and nutrition

Abstract Calcium restriction reliably produces osteoporosis in animals, but the impact of dietary calcium on age-related bone loss in man is controversial. The opinion that calcium intake is not clearly related to bone mass or to osteoporosis is well-entrenched in the nutrition literature, and has been influential in setting recommended intakes for the American public. This position rests on the poor correlation between habitual calcium intake and the incidence of osteoporosis in some non-Western countries, and on demonstrations that young men can achieve calcium balance on low intakes. However, such data neglect a variety of factors which determine calcium nutriture. These include the efficiency of mineral utilization, gonadal status, and the effect of dietary protein. It has recently been demonstrated that calcium requirements increase during adult life in women. This increase is attributable in large measure, but not completely, to estrogen deprivation associated with the menopause. In addition, the American diet is abundant in protein, a situation which may be deleterious to bone. Based on the evidence currently available, it is reasonable to propose that adolescent and young women consume one gram of calcium daily, and that this intake be increased to 1500 mg at the time of menopause.
Micelle growth and clustering in blends of polystyrene and styrene-butadiene diblock copolymer

Abstract This paper presents an investigation of the morphology of blends containing 5 wt% styrene-butadiene diblock copolymer in a high-molecular-weight polystyrene matrix. Different samples of these blends were prepared by melt compounding in an extruder and by solvent casting. Transmission electron microscopy was used to determine their morphology. The extruded blend contained well dispersed, disc-shaped micelles of the diblock. The morphology of the solvent-cast blend was strikingly different, with onion-skinned structures of diblock copolymer that spanned up to several micrometres. However, upon annealing at 200°C, the morphology of the extruded blend and of the solvent-cast blend evolved towards the same relaxed state. The micelles became more spherical, grew in size and slowly agglomerated into cluster formations. The kinetics of this evolution were observed for the extruded blend. Micelle growth and clustering rates at 200°C and also at 180°C were determined by characterizing their size, shape and spatial distribution. The micelles became more spherical quickly and formed clusters over a longer time period. The changes in micelle shape became apparent in blends annealed at 180°C for as little as 5 min. The micelle clustering, however, was only evident in the blends annealed at 200°C. The rate of clustering was quantified by plots of nearest-neighbour distributions at different times. Analysis of these plots indicates a diffusion mechanism for the clustering. The results seem to support theoretical assertions of Semenov on dynamics of block-copolymer micelles in a high-molecular-weight polymer matrix.
Selected factors associated with achievement of biology preparatory students and their follow-up to higher level biology courses

This study was undertaken to determine whether a biology preparatory course given at an urban community college was helping students to develop the proper skills and background necessary for them to successfully complete follow-up courses in biology. A group of students who enrolled in a biology preparatory course, and subsequently, a follow-up anatomy and physiology or general biology course (experimental group) was compared to a group of students who should have registered for the preparatory course, but who enrolled directly into the anatomy and physiology or general biology course (control group). It was shown that there was no significant difference in their anatomy and physiology or general biology grades. Furthermore, only 16% of the initial group of preparatory students enrolled in and passed a follow-up biology course. Examination of the preparatory group using discriminant analysis ascertained that mathematics score was the principle discriminator between pass/fail groups. A stepwise multiple regression analysis of the variables explaining the preparatory grade showed that mathematics score, reading score, and type of high school degree explained 33% of the variance. Of the students who did pass the preparatory course and enrolled in a follow-up biology class, their preparatory grade was a good predictor of their achievement (measured by follow-up course grade), as determined by multiple regression.
Combination trading with limit orders

We model the exchange of commodities that are contingent upon each other, when traders place mostly limit orders. Examples include: 1) a market of financial futures where future spreads are also traded, 2) a market of mutual funds and stocks, 3) a market of options and stocks, under the viewpoint that they are both combinations of Arrow-Debreu securities. We prove that consistent prices are optimal. We develop a fixed-point algorithm to compute an optimal price and allocation. The algorithm combines ideas from contraction mapping theory and from homotopy theory. It is much faster than a traditional linear programming approach.
Transonic wing flows using an Euler/Navier-Stokes zonal approach

Le champ d'ecoulement est divise en plusieurs zones. Les effets de paroi en soufflerie sont modelises. On obtient des solutions en bon accord avec l'experience
Probing nano-environments of peptide molecules on solid surfaces by highly charged ion secondary ion mass spectrometry

Abstract The ability to probe the chemical composition and molecular structure of solid surfaces with nanometer scale resolution through secondary ion mass spectrometry is limited by the probe beam size and by surface erosion during analysis. High secondary ion yields following the impact of individual highly charged ions allow the application of coincidence counting techniques. Statistical analysis of secondary ion emission events gives insight on the surface chemistry of single molecules. While not a direct imaging technique, coincidence analysis allows the characterization of surfaces on a length scale of a few nanometers, well beyond limits imposed by probe beam sizes. We apply this capability to the analysis of gramicidin S and its interaction with sodium impurities and 2,5-dihydroxybenzoic acid matrix molecules.
Viewpoint: Challenges in our understanding of neuroleptic induced parkinsonism

Parkinsonism remains a common and often overlooked adverse effect of almost all neuroleptic drugs, including the "atypical," or "second generation" antipsychotics. While neuroleptic induced parkinsonism (NIP) is often thought to be well understood in terms of its clinical course, pathophysiology, and treatment, this is clearly not the case, and almost all our current beliefs are based on data published decades ago of dubious merit, and recent studies which are confounded by design conflicts. This article attempts to highlight gaps in our knowledge. While there are data on the stigma associated with idiopathic Parkinson's disease, there are none on NIP, where the problem is most likely much greater. The natural course of NIP remains unknown, including the question of whether this is a risk factor for the later development of tardive dyskinesia. While treatment with anticholinergics or amantadine is the norm, there are weak and conflicting data on whether these have much value. Why quetiapine and clozapine do not worsen motor function in people with idiopathic PD, while all other neuroleptic do, remains uncertain. Neuroleptics are among the most widely prescribed medications in the United States, with 20% of nursing home residents taking them, with an increasing use for treating depression as well as psychosis, underscoring the importance of understanding NIP, the most important adverse motor effect of this class of drugs.
Identification and characterization of microRNAs and their targets in the bioenergy plant switchgrass (Panicum virgatum).

MicroRNAs (miRNAs) are a class of non-coding small endogenous RNAs with lengths of ~22 nucleotides (nt) that have been shown to regulate gene expression at the post-transcriptional levels by targeting mRNAs for degradation or by inhibiting protein translation. Although thousands of miRNAs have been identified in many species, miRNAs have not yet been identified in switchgrass (Panicum virgatum), one of the most important bioenergy crops in the United States and around the world. In this study, we identified 121 potential switchgrass miRNAs, belonging to 44 families, using a well-defined comparative genome-based computational approach. We also identified miRNA clusters and antisense miRNAs in switchgrass expressed sequences tags. These identified miRNAs potentially target 839 protein-coding genes, which can act as transcription factors, and take part in multiple biological and metabolic processes including sucrose and fat metabolism, signal transduction, stress response, and plant development. Gene ontology (GO) analysis, based on these targets, showed that 527 biological processes were involved. Twenty-five of these processes were demonstrated to participate in the metabolism of carbon, glucose, starch, fatty acid, and lignin and in xylem formation. According to pathway enrichment analysis based on Kyoto Encyclopedia of Genes and Genomes (KEGG), 118 metabolism networks were found. These networks are involved in sucrose metabolism, fat metabolism, carbon fixation, hormone regulation, oxidative stress response, and the processing of other secondary metabolites.
Classical and Alternate Pathway Activation of Complement in Pemphigus Vulgaris Lesions

Early oral and skin lesions from 6 patients with pemphigus vulgaris were examined for the presence of C1Q, C3, C3 proactivator (C3PA), and properdin, in addition to immunoglobulins (IgG, IgA, and IgM), using immunofluorescent techniques. IgG was deposited in the intercellular substance in both normal appearing areas of the lesions and pathologic areas of the lesions C1q, C3, and C3Pa, on the other hand, were deposited only an pathologic areas where acambolysis was evident. Properdin deposits were evident in 2 lesions only, and then only around individual acantholytic cells. IgA localization was seen in intercellular substance areas only in oral lesions. These studies further implicate the complement system in the pathogenesis of pemphigus vulgaris.
Human in vivo somatic mutation measured at two loci: individuals with stably elevated background erythrocyte glycophorin A (gpa) variant frequencies exhibit normal T-lymphocyte hprt mutant frequencies

Abstract A survey of glycophorin A ( gpa ) in vivo somatic cell mutation in a population of 394 healthy people from 8 to 77 years of age (mean age±SD 41±15 years) revealed a subset of 37 individuals with stably elevated allele-loss and/or allele-loss with duplication variant erythrocyte frequencies (V f ) exceeding 30×10 −6 . These 37 individuals with gpa outlier V f are significantly older ( p hprt mutant frequencies (M f ) in the peripheral blood T-lymphocytes of 27 of these individuals, together with 15 matched control individuals with unremarkable gpa V f , was undertaken to determine if these subjects also displayed elevated mutation frequencies at this independent locus indicative of globally elevated somatic mutation. The hprt M f in these 27 subjects (geometric mean 11.5×10 −6 (dispersion interval 5.8×10 −6 to 22.8×10 −6 )) was not significantly different from that observed in the 15 controls (geometric mean 12.1×10 −6 (dispersion interval 5.7×10 −6 to 25.5×10 −6 )). These M f are higher than typically reported values reflecting the older age distribution of these individuals (arithmetic mean age±SD 53±12 and 50±16 years for the subjects and controls, respectively). Taken together, these data suggest that several genetic mechanisms may be responsible for producing the gpa outlier V f observed in these subjects. The observation that hprt M f were not increased indicates that the majority did not arise by a genome-wide increased rate of somatic mutation detectable at both loci. The fixation and subsequent expansion of `jackpot' mutations at the gpa locus occurring early in embryonic/fetal development also does not appear to be a predominant mechanism. Some cases may result from a stable over-representation of gpa variant cells, perhaps associated with a marked age-dependent decrease in the number of contributing erythroid stem cells in the bone marrow. The subset that displays elevated allele-loss with duplication V f involving both gpa alleles may represent individuals with increased rates of somatic recombination. Elevations arising by this mechanism are not detected in the hprt assay, but could be confirmed using an autosomal locus in vivo somatic cell mutation endpoint such as the hla-a assay. Of primary biological significance, these results demonstrate that genetic/stochastic processes leading to the loss of heterozygosity of somatic cells occur ubiquitously in humans and in some individuals this level of somatic mosaicism can approach a frequency of 10 −3 at the gpa locus in erythroid lineage cells.
SNARE status regulates tether recruitment and function in homotypic COPII vesicle fusion.

In mammals, coat complex II (COPII)-coated transport vesicles deliver secretory cargo to vesicular tubular clusters (VTCs) that facilitate cargo sorting and transport to the Golgi. We documented in vitro tethering and SNARE-dependent homotypic fusion of endoplasmic reticulum-derived COPII transport vesicles to form larger cargo containers characteristic of VTCs (Xu, D., and Hay, J. C. (2004) J. Cell Biol. 167, 997-1003). COPII vesicles thus appear to contain all necessary components for homotypic tethering and fusion, providing a pathway for de novo VTC biogenesis. Here we demonstrate that antibodies against the endoplasmic reticulum/Golgi SNARE Syntaxin 5 inhibit COPII vesicle homotypic tethering as well as fusion, implying an unanticipated role for SNAREs upstream of fusion. Inhibition of SNARE complex access and/or disassembly with dominant-negative α-soluble NSF attachment protein (SNAP) also inhibited tethering, implicating SNARE status as a critical determinant in COPII vesicle tethering. The tethering-defective vesicles generated in the presence of dominant-negative α-SNAP specifically lacked the Rab1 effectors p115 and GM130 but not other peripheral membrane proteins. Furthermore, Rab effectors, including p115, were shown to be required for homotypic COPII vesicle tethering. Thus, our results demonstrate a requirement for SNARE-dependent tether recruitment and function in COPII vesicle fusion. We anticipate that recruitment of tether molecules by an upstream SNARE signal ensures that tethering events are initiated only at focal sites containing appropriately poised fusion machinery.
JAK2V617F and phenotype: questions galore

[Comment on Xu et al, page 339][1]The JAK2V617F mutation is associated with a range of hematologic disorders. Xu and colleagues find a surprisingly high prevalence of JAK2V617F in a large cohort of unselected patients. JAK2V617F shows a near-invariable association with polycythemia vera (PV), and
Rapamycin Suppresses Self-Renewal and Vasculogenic Potential of Stem Cells Isolated from Infantile Hemangioma

Infantile hemangioma (IH) is a common childhood vascular tumor. Although benign, some hemangiomas cause deformation and destruction of features or endanger life. The current treatments, corticosteroid or propranolol, are administered for several months and can have adverse effects on the infant. We designed a high-throughput screen to identify the Food and Drug Administration-approved drugs that could be used to treat this tumor. Rapamycin, an mTOR (mammalian target of Rapamycin) inhibitor, was identified, based on its ability to inhibit proliferation of a hemangioma-derived stem cell population, human vasculogenic cells, which we had previously discovered. In vitro and in vivo studies show that Rapamycin reduces the self-renewal capacity of the hemangioma stem cells, diminishes differentiation potential, and inhibits the vasculogenic activity of these cells in vivo. Longitudinal in vivo imaging of blood flow through vessels formed with hemangioma stem cells shows that Rapamycin also leads to regression of hemangioma blood vessels, consistent with its known anti-angiogenic activity. Finally, we demonstrate that Rapamycin-induced loss of stemness can work in concert with corticosteroid, the current standard therapy for problematic hemangioma, to block hemangioma formation in vivo. Our studies reveal that Rapamycin targets the self-renewal and vascular differentiation potential in patient-derived hemangioma stem cells, and suggests a novel therapeutic strategy to prevent formation of this disfiguring and endangering childhood tumor.
Atomic absorption analyses of eighteen elements from a single decomposition of aluminosilicate — A reply

Abstract Questions raised by Mr. Abbey's discussion of the original paper by Buckley and Cranston (1971) lack substantial significance and appropriate understanding. Trivial differences in values assigned to reference samples in no way detract from the overall precision, accuracy and convenience of the composite scheme.
Secreted effectors in Toxoplasma gondii and related species: determinants of host range and pathogenesis?

Summary Recent years have witnessed the discovery of a number of secreted proteins in Toxoplasma gondii that play important roles in host–pathogen interactions and parasite virulence, particularly in the mouse model. However, the role that these proteins play in driving the unique features of T. gondii compared to some of its nearest apicomplexan relatives (Hammondia hammondi and Neospora caninum) is unknown. These unique features include distinct dissemination characteristics in vivo and a vast host range. In this review we comprehensively survey what is known about disease outcome, the host response and host range for T. gondii, H. hammondi, and N. caninum. We then review what is presently known about recently identified secreted virulence effectors in these three genetically related, but phenotypically distinct, species. Finally we exploit the existence of genome sequences for these three organisms and discuss what is known about the presence, and functionality, of key T. gondii effectors in these three species.
Congenital protein hypoglycosylation diseases

Glycosylation is an essential process by which sugars are attached to proteins and lipids. Complete lack of glycosylation is not compatible with life. Because of the widespread function of glycosylation, inherited disorders of glycosylation are multisystemic. Since the identification of the first defect on N-linked glycosylation in the 1980s, there are over 40 different congenital protein hypoglycosylation diseases. This review will include defects of N-linked glycosylation, O-linked glycosylation and disorders of combined N- and O-linked glycosylation.
The United States Copper Industry and the Tariff

United States copper consumption increasing at a faster rate than production but not yet in excess of the latter, 142. — Apparent excess of consumption in 1930 due to decline in exports, 143. — Copper Exporters, Inc., organized in 1926, to regulate the foreign marketing of our copper, 145. — The Copper Institute, a trade association, formed in 1927, 146. — Prices rose to peak in April, 1929, were pegged at eighteen cents for a year, and fell below ten cents in October, 1930, 148. — Output restriction announced in November, 148. — Large potential new mine supply in next five years, 149. — Short-run outlook not bright, 151. — Long-run position sound, indicated by calculation of probable world demand in 1940 for primary copper, 152. — Conclusions as to future price, 154. — A tariff today would not help the industry, might in ten years, 155. — Real need is lower tariffs for United States and world, 156.
Acute kidney injury, hyperosmolality and metabolic acidosis associated with lorazepam

Background A 54-year-old male with a history of multiple admissions for alcohol intoxication was admitted to hospital with right flank pain. He received a high-dose lorazepam infusion for alcohol withdrawal during hospitalization and developed severe hyperosmolality, high anion gap metabolic acidosis, and acute kidney injury on his eighth day of hospitalization. Investigations Serum chemistries, arterial blood gas analysis, and measurement of serum propylene glycol, ethylene glycol and methanol levels. Diagnosis Propylene glycol toxicity. Management Discontinuation of lorazepam infusion, administration of fomepizole, hemodialysis for five consecutive days, hemodynamic support, and follow-up of serum osmolality as a measure of propylene glycol decay.
Negative intraventricular diastolic pressure in patients with mitral stenosis: evidence of left ventricular diastolic suction

Left ventricular diastolic pressure was evaluated in 15 patients with mitral stenosis and 16 patients with no significant heart disease to determine if a stenotic mitral valve can cause the left ventricle to produce a negative diastolic pressure, indicative of ventricular diastolic suction. The minimal level of diastolic pressure in patients with mitral stenosis ranged between 6 and −7 mm Hg; in normal subjects it did not fall below 0. The average value of minimal diastolic pressure in patients with mitral stenosis (−2 ± 1 mm Hg [mean ± standard error of the mean]) was significantly lower than in patients without significant heart disease (5 ± 1 mm Hg) (p
Protease production by cultured microglia: substrate gel analysis and immobilized matrix degradation.

The production of collagen-degrading proteases by cultured neonatal rat microglia was examined using an immobilized fibronectin-gelatin matrix coupled to a fluorescent marker and by substrate gel analysis. When microglia were plated onto the surface of the matrix and incubated under resting (nonstimulated) conditions, a small but visible amount of immobilized matrix was degraded. Treatment with lipopolysaccharide (LPS) or interleukin-1 (IL-1) significantly increased the number of microglia demonstrating substrate degradation. Substrate-SDS polyacrylamide gel electrophoresis of samples of supernatants from untreated cultured microglia indicated the presence of a 72 and a 92 kD metalloproteinase with characteristics corresponding to collagenases. Supernatants from untreated astrocyte cultures were shown to have primarily a 72 kD metalloproteinase. Proteinase activity increased on stimulation of the microglia with LPS and IL-1 in a dose-dependent fashion. These results indicate that cultured microglia release active proteases capable of degrading the extracellular matrix in a localized region. The production of proteases by activated microglia may have important physiological and pathophysiological consequences within the restricted extracellular matrix of the CNS. © 1993 Wiley-Liss, Inc.
Magnetic instabilities in ultrathin ferromagnets

We examine aspects of the dispersion relation of spin waves in ultrathin ferromagnetic films. When the easy axis is normal to the surfaces, and an external field is applied parallel to the surface, we find the state of uniform magnetization to be unstable, for magnetic fields in the near vicinity of that for which the magnetization just becomes parallel to the surface. We present results of a study of the temperature variation of the spin-wave dispersion relation, as a consequence of interactions between spin waves. From the structure of the result, we comment on the nature of the spin reorientation transition observed by Pappas, K\"amper, and Hopster. It is noted that an earlier study of temperature-dependent renormalization of thin film parameters reported by Pescia and Pokrovsky overestimates the magnitude of the temperature corrections.
Remineralization of Artificial Dentin Lesions via the Polymer-Induced Liquid-Precursor (PILP) Process

Acid-etched dentin samples with a zone of demineralized dentin were remineralized via the polymer-induced liquid-precursor (PILP) process. Poly-L-aspartic acid was used as the polymeric process-directing agent. Samples were incubated in the mineralization solution for 1- 4 weeks. Dentin samples remineralized by the PILP process presented a surface morphology very similar to the intact mineralized dentin’s architecture, in contrast to samples mineralized via the conventional nucleation and growth method (without polymer additive), which led to a superficial crust of randomly organized mineral crystals. Energy dispersive x-ray spectroscopy analysis of the PILP-mineralized samples showed the presence of calcium and phosphate ions at high levels. Since no hydroxyapatite (HA) clusters were observed on the surface of the PILP-mineralized samples, we could conclude the signal was produced from the mineral embedded within the dentin matrix. TEM and diffraction analyses suggest that both intrafibrillar and interfibrillar remineralization occurred in the demineralized dentin matrix.
Iron and Parkinson's disease: Chelators to the rescue?

The essential metal iron has long been implicated in the neuronal damage associated with Parkinson's disease. Recent findings show that iron chelation may prevent the reductions in dopamine and motor disturbances associated with this disease, and suggest the need to examine the role of dietary iron and the use of metal chelators in neurodegenerative disorders.
Qualitative case studies in operations management: Trends, research outcomes, and future research implications

Abstract Our study examines the state of qualitative case studies in operations management. Five main operations management journals are included for their impact on the field. They are in alphabetical order: Decision Sciences, International Journal of Operations and Production Management, Journal of Operations Management, Management Science, and Production and Operations Management . The qualitative case studies chosen were published between 1992 and 2007. With an increasing trend toward using more qualitative case studies, there have been meaningful and significant contributions to the field of operations management, especially in the area of theory building. However, in many of the qualitative case studies we reviewed, sufficient details in research design, data collection, and data analysis were missing. For instance, there are studies that do not offer sampling logic or a description of the analysis through which research out-comes are drawn. Further, research protocols for doing inductive case studies are much better developed compared to the research protocols for doing deductive case studies. Consequently, there is a lack of consistency in the way the case method has been applied. As qualitative researchers, we offer suggestions on how we can improve on what we have done and elevate the level of rigor and consistency.
The repolarization phase of the cardiac action potential: a comparative study of rate-induced changes in its waveform.

Abstract The rapidly equilibrating changes in the shape of the repolarization phase of the action potential of cardiac muscle (as reflected in changes in its area or voltage-time integral), which occur when the rate of stimulation (contraction) is suddenly changed, have been examined for the frog, guinea pig, chicken and rabbit heart and have been analyzed and compared. In frog and chicken heart these changes are of one kind, being describable mathematically in terms of a hypothetical variable, S , which decreases on excitation and which is regenerated with time between contractions in a simple way. In mammalian hearts, on the other hand, such changes, when they occur, mask more complex changes of another kind, a kind originally described for the rabbit heart (so-called N -type changes, 5 ), and which would seem to be a characteristic feature of action potential area-frequency relationships of mammals in general. In the guinea pig heart these N -type changes were demonstrable, although small in comparison to accompanying S -type changes. Similarly, in the rabbit heart, when cooled, the N -type changes, so characteristic of this heart, became largely obscured by the appearance of S -type changes that do not normally occur in this heart. The possible relationship between these differences in function to the abundance of well-differentiated couplings on the one hand and the relative sparsity of poorly-differentiated couplings on the other hand in these animals is discussed.
A maternal diet high in n − 6 polyunsaturated fats alters mammary gland development, puberty onset, and breast cancer risk among female rat offspring

We hypothesized that feeding pregnant rats with a high-fat diet would increase both circulating 17β-estradiol (E2) levels in the dams and the risk of developing carcinogen-induced mammary tumors among their female offspring. Pregnant rats were fed isocaloric diets containing 12% or 16% (low fat) or 43% or 46% (high fat) of calories from corn oil, which primarily contains the n − 6 polyunsaturated fatty acid (PUFA) linoleic acid, throughout pregnancy. The plasma concentrations of E2 were significantly higher in pregnant females fed a high n − 6 PUFA diet. The female offspring of these rats were fed with a laboratory chow from birth onward, and when exposed to 7,12-dimethylbenz(a)anthracene had a significantly higher mammary tumor incidence (60% vs. 30%) and shorter latency for tumor appearance (11.4 ± 0.5 weeks vs. 14.2 ± 0.6 weeks) than the offspring of the low-fat mothers. The high-fat offspring also had puberty onset at a younger age, and their mammary glands contained significantly higher numbers of the epithelial structures that are the targets for malignant transformation. Comparable changes in puberty onset, mammary gland morphology, and tumor incidence were observed in the offspring of rats treated daily with 20 ng of E2 during pregnancy. These data, if extrapolated to humans, may explain the link among diet, early puberty onset, mammary parenchymal patterns, and breast cancer risk, and indicate that an in utero exposure to a diet high in n − 6 PUFA and/or estrogenic stimuli may be critical for affecting breast cancer risk.
Behavior Traits, Semen Measurements and Fertility of White Leghorn Males

Abstract INTRODUCTION SELECTING breeding males that have a high fertilizing capacity is a matter of considerable economic importance, as pointed out by Parker (1949), who estimated that about 10 to 15 percent of all chicken eggs incubated are infertile. Hays and Sanborn (1939) indicated that the male may be largely responsible for infertility since by rotating males in pens that were low in fertility, fertility was increased considerably. Lamoreux (1940) and Sampson and Warren (1936) observed that artificial insemination of infertile females increased the fertility of these birds. It has been shown by some investigators that the libido of the male is related to fertility. Wood-Gush and Osborne (1956) selected the five cockerels highest in sex drive from a group and noted that they fertilized more females than the five lowest males. Craig, Casida and Chapman (1954) observed a strain of rats with low fertility and attributed the low fertility to …
A growth chamber study of the effect of soil concentration and plant age on the uptake of Sr and Cs by tumbleweed

Abstract Concentration ratios (CR values) for cesium and strontium were measured in tumbleweed shoots as a function of plant age and radionuclide concentration in a totally mixed soil and radionuclide system. At a given plant age, CR values were found to be independent of soil concentration over five orders of magnitude for Sr and three orders of magnitude for Cs. CR values for Sr in 4‐, 8‐, and 12‐week old plants were 10.8, 9.6, and 19, and for Cs were 0.025, 0.033, and 0.053, respectively. Based on shoot growth and tissue concentration data for Sr and Cs, the CR values appear to be dependent on shoot dry matter production, with the rate of uptake of Sr and Cs remaining relatively constant over the 12‐week period.
Shunt-Excited Flat-Plate Antennas with Applications to Aircraft Structures

A shunt-excited flat-plate antenna is a structure comprised of a thin rectangular plate and a shunt-feeding circuit formed by a wire lying in the plane of the plate parallel and close to one of its long edges, the extremities of the wire being electrically bonded to the plate, and the wire broken at its center to provide driving terminals. In this paper, the electrical characteristics of this structure are examined experimentally and in terms of a simplified mechanism by means of which these characteristics can be predicted in a qualitative manner. The effect on these characteristics of the various important geometrical parameters is illustrated by measured data, and shown to conform to the predicted behavior. Two ways in which this structure may be used as the basis for low-drag antennas for high-speed aircraft are discussed in some detail.
New Blind Multiuser Detection in DS-CDMA Using H-DE and ICA Algorithms

Hyper Differential Evolution (H-DE)is a new optimization technique. We develop a novel blind Detection algorithm based on H-DE in conjunction with Independent Component Analysis (ICA). We then apply the algorithm to the multi-user symbol estimation problem in Direct Sequence Code Division Multiple Access (DS-CDMA) systems. Blind detection is to estimate multiple symbol sequences associated with all users in the downlink of the DS-CDMA communication system using only the received wireless data and without any knowledge of the user spreading codes. Bit error rate (BER) simulation evidence of the improved performance of this novel algorithm are shown for different number of users, signal to noise ratio (SNR) and different number of symbols per user. The performance is compared with the traditional FAST ICA Detector. The results show that the proposed algorithm performs well and outperforms the FAST ICA Detector in estimating the symbol signals from the mixed CDMA received signals.
The Peruvian Agrarian Reform: Dissent from Below

This article describes the long-term reactions of two Quechua peasant communities in the Department of Cuzco in the Peruvian highlands to the major agrarian reform legislation of the past 20 years highlighting the 1969 Agrarian Reform Law of the military government of Juan Velasco Alvarado and government efforts to cooperativize expropriated haciendas. It incorporates a perspective seldom presented in discussions and analyses of government-sponsored agrarian reforms, that is, the viewpoint of some of the peasant "beneficiaries" of the reform. Peasant productive ideals expressed in the non-capitalist mode of production of the two communities are substantially at odds with the predominantly capitalist mode of production characterizing the Peruvian Agrarian Reform. The contrasting ideals of the government and the peasants are expressed as conflicts of productive ideals and rationality conflicts. The communities' decision to use the Agrarian Reform to expropriate the land from their respective hacendados and ...
Estimation of fracture compliance from tubewaves generated at a fracture intersecting a borehole

Understanding fracture compliance is important for characterizing fracture networks and for inferring fluid flow in the subsurface. In an attempt to estimate fracture compliance in the field, we developed a new model to understand tubewave generation at a fracture intersecting a borehole. Solving the dispersion relation in the fracture, amplitude ratios of generated tubewave to incident P-wave were studied over all frequency ranges. Based on the observations from the model, we propose that measuring amplitude ratios near a transition frequency can help constrain fracture compliance and aperture. The transition frequency corresponds to the regime where the viscous skin depth in the fracture is comparable to its aperture. However, measurements in the high frequency limit can place a lower bound on fracture compliance. Comparing the model to a previously published VSP dataset, we argue that compliance values of the order 10−10− 10−9 m/Pa may be possible in the field.
Apparent motion between shapes differing in location and orientation: a window technique for estimating path curvature.

When a shape is alternately presented in two positions differing in both location and orientation, apparent motion tends to be experienced over a curved path. The curvature provides evidence about principles of object motion that may have been internalized in the perceptual system. This study introduces a technique for estimating deviation from a straight path. A shape was alternately presented on the two sides of a visual partition with a “window” just wide enough to accommodate the shape. Observers adjusted the location of the window to maximize the illusion of smooth passage of the shape through the window. In accordance with theoretical expectations, estimated deviations from rectilinear motion increased with the separation between the stimuli in spatial location, angular orientation, and time.
Toward a Spiritual Praxis: The Role of Spirituality among Faculty of Color Teaching for Social Justice.

There is scant research literature on the interconnection between spirituality and the practices of faculty of color teaching social justice in the higher education classroom. This paper is based on a qualitative study that examined 15 spiritually minded activist scholars (who are all racially minoritized) in Canadian universities. The analysis focuses on how such scholars integrate spirituality into their teaching practices. This paper presents three themes: (a) responding to students in the classroom, (b) centering spirituality in the curriculum, and (c) the perils of incorporating a spiritually based pedagogy.
Whirlin, a cytoskeletal scaffolding protein, stabilizes the paranodal region and axonal cytoskeleton in myelinated axons

Myelinated axons are organized into distinct subcellular and molecular regions. Without proper organization, electrical nerve conduction is delayed, resulting in detrimental physiological outcomes. One such region is the paranode where axo-glial septate junctions act as a molecular fence to separate the sodium (Na+) channel-enriched node from the potassium (K+) channel-enriched juxtaparanode. A significant lack of knowledge remains as to cytoskeletal proteins which stabilize paranodal domains and underlying cytoskeleton. Whirlin (Whrn) is a PDZ domain-containing cytoskeletal scaffold whose absence in humans results in Usher Syndromes or variable deafness-blindness syndromes. Mutant Whirlin (Whrn) mouse model studies have linked such behavioral deficits to improper localization of critical transmembrane protein complexes in the ear and eye. Until now, no reports exist about the function of Whrn in myelinated axons. RT-PCR and immunoblot analyses revealed expression of Whrn mRNA and Whrn full-length protein, respectively, in several stages of central and peripheral nervous system development. Comparing wild-type mice to Whrn knockout (Whrn −/− ) mice, we observed no significant differences in the expression of standard axonal domain markers by immunoblot analysis but observed and quantified a novel paranodal compaction phenotype in 4 to 8 week-old Whrn −/− nerves. The paranodal compaction phenotype and associated cytoskeletal disruption was observed in Whrn −/− mutant sciatic nerves and spinal cord fibers from early (2 week-old) to late (1 year-old) stages of development. Light and electron microscopic analyses of Whrn knockout mice reveal bead-like swellings in cerebellar Purkinje axons containing mitochondria and vesicles by both. These data suggest that Whrn plays a role in proper cytoskeletal organization in myelinated axons. Domain organization in myelinated axons remains a complex developmental process. Here we demonstrate that loss of Whrn disrupts proper axonal domain organization. Whrn likely contributes to the stabilization of paranodal myelin loops and axonal cytoskeleton through yet unconfirmed cytoskeletal proteins. Paranodal abnormalities are consistently observed throughout development (2 wk-1 yr) and similar between central and peripheral nervous systems. In conclusion, our observations suggest that Whrn is not required for the organization of axonal domains, but once organized, Whrn acts as a cytoskeletal linker to ensure proper paranodal compaction and stabilization of the axonal cytoskeleton in myelinated axons.
Behavioral effects of prolonged ethanol consumption on temporal shock discrimination.

Abstract Rats were forced to drink either a 22.5% ethanol/5% saccharin solution (v/v) or a saccharin only solution for 147 days. After the termination of controlled drinking rats were trained on a free-operant lever press shock avoidance task. Rats given ethanol/saccharin were able to avoid footshocks as effectively as saccharin only treated rats. However, ethanol treated rats avoided footshocks by continually pressing the response lever as opposed to learning a temporal discrimination.
The impact of learning rate and constraints on production line performance

Learning curve theory has been an important consideration for capacity planning and bid preparation since the 1940's. Constraint theory is a relatively new approach to managing manufacturing systems. This paper examines the implications each of these theories has for the other. Several important relationships are identified using a deterministic simulation of a simple production line which is influenced by learning and the presence of a system constraint. The rate of improvement of several measures of system performance follows the learning rate, but because of the role played by the constraint, other measures of performance actually get worse.
Glutamate and Synaptic Plasticity at Mammalian Primary Olfactory Synapsesa

Glutamate is the transmitter at synapses from the olfactory nerve (ON) to mitral (Mi)/tufted cells, but very little is known about the functional properties of this synapse. This report summarizes in vitro physiological and computational modeling studies investigating glutamatergic neurotransmission at ON-->Mi cell synapses. Single ON shocks in rat main olfactory bulb (MOB) slices elicit distinct early and late spiking components triggered, respectively, by (RS)-alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA)/kainic acid (KA) and N-methyl-D-aspartate (NMDA) receptor activation. Modeling simulations showed that the placement of both AMPA/KA and NMDA receptors on Mi apical dendrites replicates the experimentally observed early and late Mi spiking responses to ON shocks. Brief, tetanic ON stimulation in vitro induced robust, selective long-term potentiation (LTP) of NMDA receptor-dependent spiking. Modeling experiments disclosed several potential mechanisms underlying the selective LTP of NMDA receptor-dependent spiking. These findings demonstrate that ON-->Mi cell transmission exhibits a novel form of plasticity whereby high frequency synaptic activity induces selective LTP of NMDA receptor-dependent spiking.
Data compression for communication networks: The delay-distortion function

The problem of data compression for communication networks is considered. The system performance criterion is the signal distortion resulting both from data compression and from average message delay through the network. The delay-distortion function is defined as the smallest message delay among all data-compression schemes that yield the given distortion value. The distortion-delay region is similarly defined. The capacity region is defined to include all incoming message rates for which there exists a set of data-compression schemes yielding a prescribed network distortion-delay value. The basic characteristics of these functions and regions are derived. In particular, it is shown that their evaluations can be performed by solving separately the source coding problem and the network's queuing problem. The distortion-delay functions and regions are explicitly derived for single channel systems.
Determination of Orthometric Height of NJI2 CORS Station

Many surveyors use the network of global positioning system (GPS) Continuously Operating Reference Stations (CORS) as accurate “free” control monuments in their projects. The National Geodetic Survey (NGS) publishes and maintains coordinates for these stations in terms of X, Y, Z, and latitude, longitude, and ellipsoidal heights. This information is very useful for horizontal positioning but not for vertical positioning. Establishing the orthometric heights of a CORS station will enhance its usefulness to surveyors and geodesists. In this paper, a method for determining orthometric heights for CORS is described and evaluated. The implementation of the proposed procedure at the NJI2 CORS station produced an orthometric height with a standard deviation of ±1 mm.
Developments in laser joining and welding of plastics using high-power laser diodes

Diode lasers are now being employed in industry for a range of applications, in particular they are starting to be used as alternatives to conventional techniques for thermal joining of plastics. This is being assisted by the use of improved reliability aluminum-free diodes and diode laser systems, partly due to a better understanding of failure mechanisms. The laser welding and related techniques are dependent on transmission of part of an infra-red beam through the upper layer of a joint and semi-quantitative assessment of this is required for specific applications. The technique is applicable not only to high average powers, but also to very low average power, in this regime delicate thin-walled components may be joined. Recent developments using derivatives of this technique have shown that a wide range of similar and dissimilar material combinations may be joined.
Public Policy Approaches to the Prevention of Heart Disease and Stroke

Those studying the causes of human disease have long recognized the important roles of social, economic, and environmental factors. Engel's1 biopsychosocial model emphasizes the importance of a hierarchy of systems from molecules to cells, to individuals and families, to societies, and to cultures in the causation of disease and its sequelae. Although specific diseases may vary in the contributions from each system, it is very clear that social and environmental factors contribute strongly to the risk of heart disease and stroke. Blackburn2 provides an extensive compendium of evidence for a significant sociocultural contribution to the cause of the major cardiovascular diseases and the need for intervention at community and societal levels. Such evidence led Rose et al3 to “seek a general change in behavioral norms and in the circumstances which facilitate their adoption.” Many of the interventions in clinical medicine constitute the “high-risk approach,” namely the clinical identification of individuals in that portion of the population at highest risk and their intensive treatment through behavioral or pharmacological means. For example, the detection and treatment of high blood cholesterol according to the Adult Treatment Panel guidelines seek to intensely treat the upper tail of the population distribution to move those high-risk individuals to more moderate levels of risk (Figure 1A).4 American Heart Association guidelines for the primary and secondary prevention of heart disease and stroke largely use the high-risk approach.5,6 In contrast, the population approach to cholesterol reduction seeks to shift the entire curve to a lower risk level through population-wide changes in diet, exercise, and weight management (Figure 1B).4 Both approaches are necessary, although analyses of the 20th century decline in coronary disease mortality suggest that the majority of the decline could be attributable to lifestyle changes in the American …