cssi/SciSciGPT-SciSciNet huggingface dataset:
Magnetic and magnetooptical properties of sputtered Fe 5 Si 3 films

Polycrystalline films of Fe 5 Si 3 have been prepared by RF sputtering from a sintered target composed of 62.5 at% Fe and 37.5 at% Si. The Faraday rotation and optical absorption were measured for these films in the visible and near infrared. At a wavelength of 6328A, room-temperature absorption (corrected for reflection) and specific Faraday rotation are 3.7 × 105cm-1and 1.3 × 105deg/cm, respectively. The rotation decreases with rising temperature and vanishes around 120°C, the Curie temperature of the films. From polar and in-plane hysteresis loop measurements the spontaneous magnetization is found to lie in the film plane. Square hysteresis loops are observed when the external field is applied in the plane of the film, and the in-plane coercive force decreases monotonically with temperature at an average rate of -2 Oe/°C as T c is approached.
Electrical and mechanical behaviors of carbon nanotube-filled polymer blends

Four carbon nanotube (CNT)-filled polymer blends, i.e., CNT-filled polyethylene terephthalate (PET)/polyvinylidene fluoride, PET/nylon 6,6, PET/polypropylene, and PET/high-density polyethylene blends, have been injection-molded and characterized in terms of their microstructures, electrical conductivities, and mechanical properties. The distribution of CNTs in the polymer blends has been examined based on their wetting coefficients and minimization of the interfacial energy. The electrical conductivity and mechanical properties have been related to the cocontinuous polymer blends, the conductive path formed by CNTs, the CNT distribution, and the intrinsic properties of the constituent polymers. It is found that to obtain a CNT-filled polymer composite with both high electrical conductivity and good mechanical properties, it is preferred that most CNTs distribute in one polymer phase, while the other polymer phase(s) remain neat. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 477–488, 2006
A quantitative assessment of the importance of barley seed α-amylase, β-amylase, debranching enzyme, and α-glucosidase in starch degradation

Extracts of germinated barley (Hordeum vulgare L.) seeds of 41 different genotypes were analyzed for their activities of alpha-amylase, beta-amylase, alpha-glucosidase, and debranching enzyme and for their abilities to hydrolyze boiled soluble starch, nonboiled soluble starch, and starch granules extracted from barley seeds with water. Linear correlation analysis, used to quantitate the interactions between the seven parameters, revealed that boiled soluble starch was not a good substrate for predicting activities of enzymes functioning in in vivo starch hydrolysis as the extracts' abilities to hydrolyze boiled soluble starch was not correlated with their abilities to hydrolyze native starch granules. Activities of alpha-amylase and alpha-glucosidase were positively and significantly correlated with the seed extracts' abilities to hydrolyze all three starches. beta-Amylase was only significantly correlated with hydrolysis of boiled soluble starch. No significant correlations existed between debranching enzyme activity and hydrolysis of any of the three starches. Interactions between the four enzymes as they functioned together to hydrolyze the three types of starch were evaluated by path coefficient analysis. alpha-Amylase contributed to hydrolyses of all three starches primarily by its direct effect (noninteractive component). This direct contribution increased as the substrate progressed from the completely artificial boiled soluble starch, to the most physiologically significant substrate, native starch granules. alpha-Glucosidase contributed to the hydrolysis of boiled soluble starch primarily by its direct effect (noninteractive) yet contributed to starch granule hydrolysis primarily via its interaction with alpha-amylase (indirect effect). The contribution of beta-amylase to hydrolysis of boiled soluble starch was direct and it did not contribute significantly to hydrolysis of native starch granules.
Intrathecal cannabilactone CB2R agonist, AM1710, controls pathological pain and restores basal cytokine levels

Spinal glial and proinflammatory cytokine actions are strongly implicated in pathological pain. Spinal administration of the anti-inflammatory cytokine interleukin (IL)-10 abolishes pathological pain and suppresses proinflammatory IL-1β and tumor necrosis factor alpha (TNF-α). Drugs that bind the cannabinoid type-2 receptor (CB(2)R) expressed on spinal glia reduce mechanical hypersensitivity. To better understand the CB(2)R-related anti-inflammatory profile of key anatomical nociceptive regions, we assessed mechanical hypersensitivity and protein profiles following intrathecal application of the cannabilactone CB(2)R agonist, AM1710, in 2 animal models; unilateral sciatic nerve chronic constriction injury (CCI), and spinal application of human immunodeficiency virus-1 glycoprotein 120 (gp120), a model of peri-spinal immune activation. In CCI animals, lumbar dorsal spinal cord and corresponding dorsal root ganglia (DRG) were evaluated by immunohistochemistry for expression of IL-10, IL-1β, phosphorylated p38-mitogen-activated-kinase (p-p38MAPK), a pathway associated with proinflammatory cytokine production, glial cell markers, and degradative endocannabinoid enzymes, including monoacylglycerol lipase (MAGL). AM1710 reversed bilateral mechanical hypersensitivity. CCI revealed decreased IL-10 expression in dorsal spinal cord and DRG, while AM1710 resulted in increased IL-10, comparable to controls. Adjacent DRG and spinal sections revealed increased IL-1β, p-p38MAPK, glial markers, and/or MAGL expression, while AM1710 suppressed all but spinal p-p38MAPK and microglial activation. In spinal gp120 animals, AM1710 prevented bilateral mechanical hypersensitivity. For comparison to immunohistochemistry, IL-1β and TNF-α protein quantification from lumbar spinal and DRG homogenates was determined, and revealed increased DRG IL-1β protein levels from gp120, that was robustly prevented by AM1710 pretreatment. Cannabilactone CB(2)R agonists are emerging as anti-inflammatory agents with pain therapeutic implications.
On building minimum cost communication networks

The notion of an „exact” test for improving network solutions is discussed. Computational results are presented which indicate the power of „exact” tests relative to current marginal pricing schemes. It is conjectured that each cycle in an optimal solution must contain at least links, where the cost of a link of length l and capacity y is proportional to 1·yα, 0 ≦ α ≦ 1. A simple „exact” test is presented for the one termianl TELPAK problem.
The quinoline pathway of tryptophan oxidation in Pseudomonas: synthesis of 7,8-dihydroxykynurenic acid and kynurenic acid-C14.

The enzymic synthesis of kynurenic acids-2- and 3-C14 from the correspondingly labeled tryptophans is described. The method utilized successive treatment with tryptophan pyrrolase, formamidase, and l-amino acid oxidase. 7,8-Dihydroxykynurenic acid has been synthesized by application of the Conrad-Limpach method to 2,3-dimethoxyaniline and diethyloxalacetate. These compounds are of importance in the elucidation of the pathway of tryptophan metabolism by certain bacteria of the Pseudomonas species group.
Synthesis and evaluation of estrogen receptor ligands with bridged oxabicyclic cores containing a diarylethylene motif: Estrogen antagonists of unusual structure

A new series of ligands for the estrogen receptor (ER) based on a three-dimensional structural motif consisting of a bridged oxabicyclic core (7-oxabicyclo[2.2.1]heptene or heptadiene) were synthesized and examined for their receptor binding activity and as regulators of transcription through the two ER subtypes, ER alpha and ER beta. The prototypical ligands also contain a 1,2-diarylethylene motif, common to many nonsteroidal estrogens, as an embellishment on the oxabicyclic core. Thus, these ligands bear peripheral groups typically found in ER ligands, built here upon an overall three-dimensional core topology that is unusual for these targets. Most of these compounds were conveniently synthesized by a Diels-Alder reaction of various 3,4-diarylfurans with a variety of dienophiles, neat and under mild conditions in the absence of catalysts. Some of the synthesized compounds display good binding affinity for the ER, and in transcription assays, the highest affinity compounds are antagonists on both ERs. Molecular modeling studies suggest a structural basis for the antagonist activity of these compounds. These compounds, based on the bicyclo[2.2.1]core system, expand the structural diversity of ligands that can be antagonists for the estrogen receptors.
The mechanics of splitting a strip through penetration with a sharp wedge

This paper deals with the mechanics involved in splitting a strip through penetration with a sharp wedge along the center line. First, a quasi-static problem is considered. The crack propagation can be associated with the loss in stability when the applied load reaches the critical value for bifurcation. Next, the static problem is extended to a dynamic case by including the inertia force of the wedge in the analysis. An initial value problem is formulated for the motion of the wedge. For any given weight of the wedge, the critical velocity of the wedge for indefinite crack propagation can be determined by means of the theory of dynamic stability. Finally, the case of splitting a strip under repeated applications of impulsive load is considered. The critical number of applications of impulsive load for indefinite crack propagation is determined numerically.
A Petri net approach to modeling and performance analysis of Fiber Data Distributed Interface (FDDI) network

This paper presents a Petri net approach to modeling and performance analysis of the Fiber Distributed Data Interface (FDDI) network. The service type described in the "Timed Token Rotation" protocol, supporting both synchronous and asynchronous traffic, is modeled using stochastic Petri nets, and its performance is conducted for both symmetric/asymmetric cases. In order to deal with large networks without creating very long Markov chains, a modified N station network is introduced. The correlation between the voice and data throughput rate, and the parameters of the system, such as the network load and the network speed are investigated. >
Effect of dietary fat and food consistency on gastroparesis symptoms in patients with gastroparesis.

Background Nutrition therapy for gastroparesis focuses on reducing meal size, fiber, fat intake, and increasing liquids intake relative to solid foods. Evidence to support these dietary interventions has been anecdotal. The aim of this study was to determine the effect of fat intake and solid/liquid meal consistency on symptoms in gastroparesis. Methods Twelve patients with gastroparesis were studied on four separate days receiving one of four meals each day in a randomized order: high-fat solid, high-fat liquid, low-fat liquid, and low-fat solid meal. At each visit, eight gastrointestinal symptoms were rated from 0 (none) to 4 (very severe) every 15 min, before and for 4 h after meal ingestion. Key Results There was an increase in the total symptom score in the following order: high-fat solid > low-fat solid > high-fat liquid > low-fat liquid. For the high-fat solid meal, symptoms remained elevated throughout the 4 h postprandial period. Severity of nausea more than doubled after the high-fat solid meal, whereas the low-fat liquid meal caused the least increase in nausea. Conclusions & Inferences A high-fat solid meal significantly increased overall symptoms among individuals with gastroparesis, whereas a low-fat liquid meal had the least effect. With respect to nausea, low-fat meals were better tolerated than high-fat meals, and liquid meals were better tolerated than solid meals. These data provide support for recommendations that low-fat and increased liquid content meals are best tolerated in patients with symptomatic gastroparesis.
Democracy and Gender Inequality in Education: A Cross-National Examination

This Research Note examines the role democracy plays in explaining the disparity in educational attainment between men and women in a cross-national context. Policies designed to improve education figure prominently in recent attempts by governments, international institutions and non-governmental organizations (NGOs) to stimulate economic development. The recent emphasis on education is grounded in a well-established literature in economics on the rate of return on investment in education and in a fairly new stream of research in economics – endogenous growth theory – that suggests knowledge is the generative force of economic growth. Although a majority of the work in both literatures focuses on aggregate levels of educational attainment (usually enrolment ratios or literacy rates), a growing body of evidence identifies women’s educational attainment relative to men’s as a crucial variable in explaining the wide variation in economic development throughout the world. In addition to its direct impact on economic growth, women’s education may indirectly affect economic performance in a number of important ways: through its impact on health, fertility and infant mortality. Previous empirical work shows that women’s education has a strong negative effect on fertility and infant mortality. Moreover, family health practices improve in direct proportion to female education. According to the World Bank, countries that achieved universal primary education for boys in 1965 but lagged far behind in educating girls had about twice the infant mortality and fertility rates in 1985 of countries with smaller gender gaps.
Experimental and numerical analysis of delamination growth in double cantilever laminated beams

Delamination crack growth in laminated composites is investigated using experiments and finite element (FE) models. Tests are performed on cross-ply graphite/epoxy specimens under static conditions. The load–displacement response is monitored in the tested coupons along with crack length. The FE models employ a cohesive layer that is used to simulate the debonding and crack propagation. The cohesive parameters are calibrated from the experimental load–displacement curves. Crack growth and strain measurements are compared with those from the FE models. The predicted results from the FE models are in good agreement with the test results. The same modeling approach is also used to simulate crack propagation in the transverse direction of a notched laminate. The proposed FE analysis with cohesive layers can simplify fracture toughness assessment in multilayered specimens. 2002 Elsevier Science Ltd. All rights reserved.
Weekend versus weekday admission and mortality from myocardial infarction.

BACKGROUND Management of acute myocardial infarction requires urgent diagnostic and therapeutic procedures, which may not be uniformly available throughout the week. METHODS We examined differences in mortality between patients admitted on weekends and those admitted on weekdays for a first acute myocardial infarction, using the Myocardial Infarction Data Acquisition System. All such admissions in New Jersey from 1987 to 2002 (231,164) were included and grouped in 4-year intervals. RESULTS There were no significant differences in demographic characteristics, coexisting conditions, or infarction site between patients admitted on weekends and those admitted on weekdays. However, patients admitted on weekends were less likely to undergo invasive cardiac procedures, especially on the first and second days of hospitalization (P<0.001). In the interval from 1999 to 2002 (59,786 admissions), mortality at 30 days was significantly higher for patients admitted on weekends (12.9% vs. 12.0%, P=0.006). The difference became significant the day after admission (3.3% vs. 2.7%, P<0.001) and persisted at 1 year (1% absolute difference in mortality). The difference in mortality at 30 days remained significant after adjustment for demographic characteristics, coexisting conditions, and site of infarction (hazard ratio, 1.048; 95% confidence interval [CI], 1.022 to 1.076; P<0.001), but it became nonsignificant after additional adjustment for invasive cardiac procedures (hazard ratio, 1.023; 95% CI, 0.997 to 1.049; P=0.09). CONCLUSIONS For patients with myocardial infarction, admission on weekends is associated with higher mortality and lower use of invasive cardiac procedures. Our findings suggest that the higher mortality on weekends is mediated in part by the lower rate of invasive procedures, and we speculate that better access to care on weekends could improve the outcome for patients with acute myocardial infarction.
Determinants and perfect matchings

We give a combinatorial interpretation of the determinant of a matrix as a generating function over Brauer diagrams in two different but related ways. The sign of a permutation associated to its number of inversions in the Leibniz formula for the determinant is replaced by the number of crossings in the Brauer diagram. This interpretation naturally explains why the determinant of an even antisymmetric matrix is the square of a Pfaffian.
Characteristics of Bacteroides fragilis lacking the major outer membrane protein, OmpA.

OmpA1 is the major outer membrane protein of the Gram-negative anaerobic pathogen Bacteroides fragilis. We identified three additional conserved ompA homologues (ompA2–ompA4) and three less homologous ompA-like genes (ompAs 5, 6 and 7) in B. fragilis. We constructed an ompA1 disruption mutant in B. fragilis 638R (WAL6 ΩompA1) using insertion-mediated mutagenesis. WAL6 ΩompA1 formed much smaller colonies and had smaller, rounder forms on Gram stain analysis than the parental strain or other unrelated disruption mutants. SDS-PAGE and Western blot analysis (with anti-OmpA1 IgY) of the OMP patterns of WAL6 ΩompA1 grown in both high- and low-salt media did not reveal any other OmpA proteins even under osmotic stress. An ompA1 deletant (WAL186ΔompA1) was constructed using a two-step double-crossover technique, and an ompA ‘reinsertant’, WAL360+ompA1, was constructed by reinserting the ompA gene into WAL186ΔompA1. WAL186ΔompA1 was significantly more sensitive to exposure to SDS, high salt and oxygen than the parental (WAL108) or reinsertant (WAL360+ompA1) strain. No significant change was seen in MICs of a variety of antimicrobials for either WAL6 ΩompA1 or WAL186ΔompA1 compared to WAL108. RT-PCR revealed that all of the ompA genes are transcribed in the parental strain and in the disruption mutant, but, as expected, ompA1 is not transcribed in WAL186ΔompA1. Unexpectedly, ompA4 is also not transcribed in WAL186ΔompA1. A predicted structure indicated that among the four OmpA homologues, the barrel portion is more conserved than the loops, except for specific conserved patches on loop 1 and loop 3. The presence of multiple copies of such similar genes in one organism would suggest a critical role for this protein in B. fragilis.
Differentiation of human fetal multipotential neural progenitor cells to astrocytes reveals susceptibility factors for JC virus

Viral infections of the central nervous system (CNS) are of increasing concern, especially among immunocompromised populations. Rodent models are often inappropriate for studies of CNS infection, as many viruses, including JC virus (JCV) and HIV, cannot replicate in rodent cells. Consequently, human fetal brain-derived multipotential CNS progenitor cells (NPCs) that can be differentiated into neurons, oligodendrocytes, or astrocytes have served as a model in CNS studies. NPCs can be nonproductively infected by JCV, while infection of progenitor-derived astrocytes (PDAs) is robust. We profiled cellular gene expression at multiple times during differentiation of NPCs to PDAs. Several activated transcription factors show commonality between cells of the brain, in which JCV replicates, and lymphocytes, in which JCV is likely latent. Bioinformatic analysis determined transcription factors that may influence the favorable transcriptional environment for JCV in PDAs. This study attempts to provide a framework for understanding the functional transcriptional profile necessary for productive JCV infection.
A time-dependent logistic hazard function for modeling variable age of onset in analysis of familial diseases.

The paper presents an extension of the regressive logistic models proposed by Bonney [Biometrics 42:611-625, 1986], to address the problems of variable age-of-onset and time-dependent covariates in analysis of familial diseases. This goal is achieved by using failure time data analysis methods, and partitioning the time of follow up in K mutually exclusive intervals. The conditional probability of being affected within the kth interval (k = 1...K) given not affected before represents the hazard function in this discrete formulation. A logistic model is used to specify a regression relationship between this hazard function and a set of explanatory variables including genotype, phenotypes of ancestors, and other covariates which can be time dependent. The probability that a given person either becomes affected within the kth interval (i.e., interval k includes age of onset of the person) or remains unaffected by the end of the kth interval (i.e., interval k includes age at examination of the person) are derived from the general results of failure time data analysis and used for the likelihood formulation. This proposed approach can be used in any genetic segregation and linkage analysis in which a penetrance function needs to be defined. Application of the method to familial leprosy data leads to results consistent with our previous analysis performed using the unified mixed model [Abel and Demenais, Am J Hum Genet 42:256-266, 1988], i.e., the presence of a recessive major gene controlling susceptibility to leprosy. Furthermore, a simulation study shows the capability of the new model to detect major gene effects and to provide accurate parameter estimates in a situation of complete ascertainment.
Evaluation of Corrosion Processes Affecting the Performance of Alloy 22 as a Proposed Waste Package Material

This paper presents recent work on evaluating localized corrosion and stress corrosion cracking, two corrosion processes that are important to the long-term performance of Alloy 22 (58Ni-22Cr-13Mo-3W-4Fe). This alloy is the material preferred by the U.S. Department of Energy (DOE) for the outer container of the waste package to be used in the proposed high-level radioactive waste repository at Yucca Mountain, Nevada. It was found that both welded and thermally aged materials are more susceptible to localized corrosion in chloride solutions at temperatures above 60 EC than the mill-annealed material. This observation suggests that welding and certain post-welding operations may decrease the estimated life of the waste packages. However, no stress corrosion crack growth was observed in concentrated chloride solutions and simulated, concentrated groundwater at 95 EC when precracked compact tension specimens were tested under both constant and cycling loading.
Doubly Recursive Multivariate Automatic Differentiation

system. That's right. The automatic differentiation system never formulates a symbolic expression for the derivative. Automatically calling on something like Mathematica to produce a symbolic derivative, and then plugging in a value for x is the wrong image entirely. Automatic differentiation is something completely different. Well OK, but so what? Symbolic algebra systems are so prevalent and powerful today, why should we be concerned with avoiding symbolic methods? There are two answers. The first is practical. Symbolic generation of derivatives can lead to exponential growth in the length of expressions. That causes computational problems in real applications. Accordingly, there is a practical applied side to the subject of automatic differentiation, as witnessed by the serious attention of computer scientists and numerical analysts [3, 4]. The second answer is more mathematical. It is a relatively easy task to create a single variable automatic differentiation system capable of evaluating first derivatives. In fact, writing in this MAGAZINE in 1986, Rall [10] gives a beautiful presentation of just such a system. What is mathematically interesting is an amazingly elegant extension of the one-variable/one-derivative system that handles essentially any number of variables and derivatives. The extension is recursively defined, employing an induction on both the number of variables and the number of derivatives, and using fundamental definitions that are virtually identical to the ones used in Rall's system. The purpose of this paper is to present the recursive automatic differentiation system. To set the stage, we will begin with a brief review of Rall's one-variable/onederivative system, followed by an example of the recursive system in action. Then the mathematical formulation of the recursive system will be presented. The paper will end with a brief discussion of practical issues related to the recursive system.
Effects of Mg-Fe (super 2+) substitution in calcite-structure carbonates; thermoelastic properties

In situ X-ray diffraction has been carried out on two siderite samples of different Fe contents simultaneously at high pressure and high temperature in a DIA-type, large-volume apparatus. Unit-cell volumes, measured up to 8.9 GPa and 1073 K have been analyzed using a Birch-Murnaghan equation of state. With K09 fixed at 4, the derived equation of state parameters are: K0 5 117(1) GPa, ()K/)T)P 52 0.031(3) GPa/K, and a(K 21 T for the Mg-Fe 21 solid solution with 60 mol% FeCO3. These results, along with results obtained previously on magnesite using the same experimental technique, indicate that Fe 21 substi- tution for Mg in the R3c carbonates results in a linear increase of the room-temperature bulk modulus and its temperature derivative with increasing Fe content. The bulk modulus increases by more than 10% from MgCO3 to FeCO3. This bulk modulus-composition re- lationship is mainly attributed to differences in the compressibility of the a axis with increasing Fe content, even though the c axis is more than twice as compressible as the a axis for a given composition. The bulk modulus-volume relationship in the Mg-Fe 21 car- bonates studied is consistent with trends reported in other ferromagnesian minerals, such as oxides, olivines, pyroxenes, silicate spinels, and garnets, in the sense that it deviates from the empirical prediction that the product of K0 and V0 is constant. In addition, these observations are consistent with previous suggestions that substitution of alkaline earth elements by the 3-d transition metals may yield a different bulk modulus-volume relationship.
Neuropsychological correlates of recollection and familiarity in normal aging

The dual-process model of recognition memory proposed by Jacoby (1991; see also Mandler, 1980) postulates the existence of two independent components of recognition memory: a conscious retrieval process (recollection) and an automatic component (familiarity). Older adults appear to be impaired in recollection, but findings with respect to familiarity have been mixed. Studies of the brain bases of these components, using neurological patients, have also been inconclusive. We examined recollection and familiarity, using the process dissociation procedure, in older adults characterized on the basis of both their frontal and their medial temporal lobe function. Findings suggest that only some older adults, depending on their neuropsychological status, are impaired in recollection and/or familiarity: Recollection seems to involve both frontal and medial temporal lobe function, whereas familiarity appears to be dependent only on function associated with the medial temporal lobes.
QUANTITATIVE DETERMINATION OF CALCITE AND DOLOMITE IN PURE CARBONATES AND LIMESTONES

Summary Calcite and dolomite were differentiated quantitatively from calcite-dolomite mixtures and limestones by a method based on the quantitative dissolution of calcite in pH 5.85N citrate buffer. The acidity and chelating ability of citrate favoured greatly the dissolution of calcite to that of dolomite. The method consisted of determination of citrate-soluble Ca and Mg which, in conjunction with a Ca and Mg analysis of the residue, or a determination of total CO3 in the system, allowed calculation of the calcite and dolomite contents of the sample. Analyses of artificially prepared mixtures and limestone samples gave essentially the same calcite and dolomite contents when determined by the residue and total CO3 methods. The residue method is to be preferred because error can be reduced by determination of the actual Ca:Mg ratio of the dolomite. However, the total CO3 method would be superior for heterogeneous systems, such as soils, since dissolution of dolomite in the residue by strong acid treatment may introduce errors from the dissolution of non-carbonate Ca and Mg minerals.
The Horse and Slave Trade Between the Western Sahara and Senegambia

Following the late fifteenth- and sixteenth-century cavalry revolution in Senegambia, the horse and slave trade became a major sector of the desert-edge political economy. Black African states imported horses from North Africa and the western Sahara in exchange for slaves. Over time, under conditions of increasing aridity, the zone of desert horse-breeding was pushed south, and through crossbreeding with the small disease-resistant indigenous horses of the savanna, new breeds were created. Although the savanna remained an epidemiologically hostile environment for the larger and more desirable horses bred in North Africa, in the high desert and along the desert fringe, Black African states continued to import horses in exchange for slaves into the period of French colonial rule.The evidence assembled on the horse trade into northern Senegambia raises the difficult issue of the relative quantitative importance of the Atlantic and Saharan/North African slave trades and calls into question the assumption that the Atlantic slave trade was the larger of the two. Most available evidence concerns the Wolof kingdoms of Waalo and Kajoor. It suggests that the volume of slaves exported north into the desert from Waalo in the late seventeenth century was probably at least ten times as great as the volume of slaves exported into the Atlantic slave trade. For both Waalo and Kajoor, this ratio declined during the first half of the eighteenth century as slave exports into the Atlantic markets increased. The second half of the eighteenth century saw an increase in predatory raiding from the desert which produced an additional flow of north-bound slaves. For Waalo and Kajoor – and probably for the other Black African states of northern Senegambia – the flow of slaves north to Saharan and North African markets probably remained the larger of the two export volumes over the eighteenth century. This northward flow of slaves continued strong after the abolition of the Atlantic slave trade and was only shut down with the imposition of French colonial authority.
Variable optical buffer using slow light in semiconductor nanostructures

A compact variable all-optical buffer using semiconductor quantum dot (QD) structures is proposed and analyzed. The buffering effect is achieved by slowing down the optical signal using an external control light source to vary the dispersion characteristic of the medium via an electromagnetically induced transparency effect. We present a theoretical investigation of the criteria for achieving slow light in semiconductor QDs. A QD structure in the presence of strain is analyzed with the inclusion of polarization-dependent intersubband dipole selection rules. Experimental methods to synthesize and the measurements of coherent properties in state-of-the-art QDs are surveyed. Slow-light effects in uniform and nonuniform QDs are compared. Finally, optical signal propagation through the semiconductor optical buffer is presented to demonstrate the feasibility for practical applications.
Influence of Crude Fiber in the Ration on Efficiency of Feed Utilization by Dairy Cows

Summary A feeding experiment has been carried out with different levels of crude fiber in the feed of dairy cows of Holstein-friesian breed. Except for fiber, other nutritive factors (digestible protein and T.D.N.) were kept alike in different rations. A sufficient supply of vitamins and minerals also was provided. Four different rations were tried, namely, A with 60 lb. Napier grass, B with 40 lb. Napier grass, C with 20 lb. Napier grass daily per cow and D with no Napier grass. The balance needed of protein and T.D.N. was made up of pineapple bran, soybean oil meal, meat meal, fish meal and molasses. The crude fiber content for different rations were in percentage of dry matter as follows: A, 22.7 per cent; B, 19.6 per cent; C, 16.1 per cent; and D, 12.0 per cent. The effect of the level of crude fiber in the feed upon milk production was highly significant. With increase over 16 per cent in crude fiber content of the feed, a drop in milk production occurred, regardless of the fact that equal amounts of T.D.N. and digestible protein were fed. The average daily yield of 4 per cent F.C.M. per cow for 12 wk. was 20.6 lb.on ration A, 21.7 lb. on ration B, 23.4 lb. on ration C, and 23.8 lb. on ration D. Pulse rates per minute for cows with no roughage were 62, and increased to 69 with roughage. The statistical significance of this influence of rations fell close to the 1 per cent point. For high milk production, the crude fiber level in the feed should not exceed 16 per cent when calculated on basis of dry matter content of the ration. This holds true for feeds such as mature Napier grass and pineapple bran as major constituents of the rations.
Chronology of Quaternary glaciations in East Africa

Abstract A new glacial chronology for equatorial East Africa is developed using in situ cosmogenic 36 Cl measured in 122 boulders from moraines on Mount Kenya and Kilimanjaro. The oldest deposits sampled on Kilimanjaro yield a limiting 36 Cl age of >360 calendar kyr (all 36 Cl ages are in calendar years, cal. kyr or cal. yr). On Mount Kenya, the oldest moraines give ages of 355–420 kyr (Liki I) and 255–285 kyr (Teleki). Given the uncertainty in our 36 Cl ages, the Liki I moraine may correspond to either marine isotope stage 10 or 12, whereas the Teleki moraine correlates with stage 8. There is no evidence for stage 6 on either mountain. The Liki II moraines on Mt. Kenya and moraines of the Fourth Glaciation on Kilimanjaro give ages of 28±3 kyr and 20±1 kyr, respectively. They represent the last glacial maximum (LGM) and correlate with stage 2 of the marine isotope record. A series of smaller moraines above the LGM deposits record several readvances that occurred during the late glacial. On Mt. Kenya, these deposits date to 14.6±1.2 kyr (Liki IIA), 10.2±0.5 kyr (Liki III), 8.6±0.2 kyr (Liki IIIA) and ∼200 yr (Lewis); the corresponding deposits on Kilimanjaro have mean ages of 17.3±2.9 kyr (Fourth Glaciation–Saddle), 15.8±2.5 kyr (Little Glaciation–Saddle), and 13.8±2.3 kyr (Fourth Glaciation–Kibo). These data indicate that the climate of the tropics was extremely variable at the end of the last glacial cycle.
Polymer-bonded magnets: Part I. Analytic thermogravimetry to determine the effect of surface modification on dispersion of Nd–Fe–B fillers

The degree of mixing is a critical factor in controlling the magnetic properties and mechanical properties of polymer-bonded magnets. Pretreatment of the NdFeB fillers with a silane coupling agent improved the degree of mixing of the fillers in the polymer matrix. The observed improvement in the degree of mixing of the silanetreated fillers was ascribed to good wetting as evidenced by viscosity reduction of the coupled polymer-bonded magnets. However, traditional materials characterization methods could not be used to quantitatively determine the degree of mixing of the polymer-bonded magnets. This paper describes use of thermogravimetric analysis to quantify the degree of mixing of polymer-bonded magnets. The intensity of segregation of the fillers was calculated from the measured weight change of the magnetic filler in the samples. The results of this work showed that the thermogravimetric analysis method was useful in determining the degree of mixing of NdFeB fillers in polymer-bonded magnets.
Allozymic relationships of Arceuthobium campylopodum and allies in California.

Abstract Allozyme electrophoresis was used to examine genetic variation among populations of the dwarf mistletoes parasitic on Pinus ponderosa ( Arceuthobium campylopodum ) and P. sabiniana, P. muricata and P. radiata ( A. occidentale ). Twenty-seven populations were sampled throughout California and genotypes at nine electrophoretic loci were determined. UPGMA cluster analysis from genetic distances and distance Wagner trees indicate the coastal taxon parasitic on bishop and Monterey pine is a distinct species ( A. littorum ) from populations of A. campylopodum and A. occidentale . Cluster analysis does not, however, segregate the ponderosa and digger pine dwarf mistletoes into distinct groups. In populations where both host species were parasitized, no significant genetic differentiation was noted between the two putative mistletoe taxa. The results of this allozyme analysis support the concept of a single biological species for A. campylopodum and A. occidentale .
Cognitive Function After the Initiation of Adjuvant Endocrine Therapy in Early-Stage Breast Cancer: An Observational Cohort Study

Purpose This report examines cognitive complaints and neuropsychological (NP) testing outcomes in patients with early-stage breast cancer after the initiation of endocrine therapy (ET) to determine whether this therapy plays any role in post-treatment cognitive complaints. Patients and Methods One hundred seventy-three participants from the Mind Body Study (MBS) observational cohort provided data from self-report questionnaires and NP testing obtained at enrollment (T1, before initiation of ET), and 6 months later (T2). Bivariate analyses compared demographic and treatment variables, cognitive complaints, depressive symptoms, quality of life, and NP functioning between those who received ET versus not. Multivariable linear regression models examined predictors of cognitive complaints at T2, including selected demographic variables, depressive symptoms, ET use, and other medical variables, along with NP domains that were identified in bivariate analyses. Results Seventy percent of the 173 MBS participants ...
A New Syllabication Strategy and Reading Achievement.

Abstract A new syllabication strategy was designed which did not require prior pronunciation of the word to be divided. This syllabication strategy was based on an analysis of the 405 most common polysyllabic words. Three rules accounted for correctly dividing 87 percent of these words. Fourteen classes of third and fourth graders were the subjects of this investigation. These subjects were given 15 minutes of instruction daily for 15 weeks. All instruction was carried out by the subjects' regular classroom teachers. Instruction was done with the shole class and this instruction replaced the syllabication instruction outlined in the basal reader used. In addition to the new syllabication strategy, subjects were given practice in comparing and contrasting unknown words to words already known and in pronouncing these words. A two‐way multivariate analysis of multiple covariance revealed no significant differences between the experimental and control groups on vocabulary or reading comprehension. This study ...
Genomic Prediction Accounting for Residual Heteroskedasticity

Whole-genome prediction (WGP) models that use single-nucleotide polymorphism marker information to predict genetic merit of animals and plants typically assume homogeneous residual variance. However, variability is often heterogeneous across agricultural production systems and may subsequently bias WGP-based inferences. This study extends classical WGP models based on normality, heavy-tailed specifications and variable selection to explicitly account for environmentally-driven residual heteroskedasticity under a hierarchical Bayesian mixed-models framework. WGP models assuming homogeneous or heterogeneous residual variances were fitted to training data generated under simulation scenarios reflecting a gradient of increasing heteroskedasticity. Model fit was based on pseudo-Bayes factors and also on prediction accuracy of genomic breeding values computed on a validation data subset one generation removed from the simulated training dataset. Homogeneous vs. heterogeneous residual variance WGP models were also fitted to two quantitative traits, namely 45-min postmortem carcass temperature and loin muscle pH, recorded in a swine resource population dataset prescreened for high and mild residual heteroskedasticity, respectively. Fit of competing WGP models was compared using pseudo-Bayes factors. Predictive ability, defined as the correlation between predicted and observed phenotypes in validation sets of a five-fold cross-validation was also computed. Heteroskedastic error WGP models showed improved model fit and enhanced prediction accuracy compared to homoskedastic error WGP models although the magnitude of the improvement was small (less than two percentage points net gain in prediction accuracy). Nevertheless, accounting for residual heteroskedasticity did improve accuracy of selection, especially on individuals of extreme genetic merit.
Cesarean Delivery in Adolescents

Abstract Study Objective To examine the effect of maternal age on indication for primary cesarean delivery in low-risk nulliparous women. Design Retrospective cohort study. Setting Urban academic tertiary care center. Participants Nulliparous women younger than 35 years of age delivering vertex-presenting singletons at term. Interventions Participants underwent spontaneous, operative or cesarean delivery. Main Outcome Measures Mode of delivery, indication, and timing of cesarean delivery. Results Adolescents were half as likely to undergo cesarean delivery overall (odds ratio [OR], 0.48; 95% confidence interval [CI], 0.43-0.54), and more than one-third less likely to undergo cesarean delivery in labor (OR, 0.59; 95% CI, 0.53-0.66). Adjustment for potential confounders did not alter the strength of these associations. Adolescents were half as likely to undergo cesarean delivery for failure to progress (OR, 0.49; 95% CI, 0.43-0.54). There was no difference in the odds of cesarean delivery for nonreassuring fetal status (OR, 0.91; 95% CI, 0.77-1.06), or genital herpes (OR, 1.44; 95% CI, 0.57-3.68). Induction, macrosomia, oxytocin augmentation, and any labor complication were all associated with increased risk of cesarean delivery. There was no difference in the duration of second stage for adolescents who delivered by cesarean delivery compared with adults (240.0 vs 237.7 minutes; P = .84), but adolescents who delivered vaginally had a second stage that was one-third shorter than adults (62.5 vs 100.3 minutes; P Conclusion Adolescents are half as likely to undergo primary cesarean delivery overall, and 40% less likely to undergo a primary cesarean delivery in labor, even after adjustment for multiple maternal, neonatal, and labor characteristics. This difference is not explained by differences in the duration of the second stage of labor.
Unreasonable Searches and Seizures: Rights and Liberties Under the Law, Chapter 4

Unreasonable Searches and Seizures examines the Fourth Amendment from its historical origins through its early development to current controversies. Through thorough and well-balanced research this book provides a rich and comprehensive source of information about search and seizure law. The book is clearly written, providing simple and precise explanations of complicated constitutional issues without obscuring the central and important problems which these issues present. This book serves as a basis for evaluating the question of the Fourth Amendments continuing relevance in seeking the balance between the protection of individual liberty and the demand for effective law enforcement. In accomplishing its purpose the book examines five distinct areas of search and seizure law. First, it discusses the role of search and seizure law in our society and its implications for the American political system. Secondly, the book reveals the origins and early development of search and seizure law by looking at the English, colonial, and revolutionary experiences from which it arose. Thirdly, it explores the evolution and devolution of Fourth Amendment protections from the late nineteenth century through the opening years of the twenty-first century by analyzing significant judicial decisions. Lastly, the book speculates on recent trends in search and seizure jurisprudence by examining the issues and controversies that have been most visible in the last decade, with particular emphasis on the potential adverse effects of the USA PATRIOT Act on Fourth Amendment protections.
Problem Posing as an Integral Component of the Mathematics Curriculum: A Study with Prospective and Practicing Middle-School Teachers

Details are presented of a study in which problem posing was an integral component of a mathematical modelling class for preservice and practicing middle-school teachers. One of the activities involved a project in which students individually planned and drafted mathematical modelling problems. Students then shared their draft problems with their peers before developing and presenting final versions of their problems to the class. Their personal reflections on the project formed an important part of the activity. Results are discussed in terms of an Active Learning Framework, and characteristics of a pedagogy for problem posing are proposed.
Management of the great mimicker: Meckel cave tumors

BACKGROUND: Meckel cave tumors are often asymptomatic and have a sufficiently characteristic magnetic resonance imaging/computed tomography signature that allows treatment/surveillance decisions to be made without biopsy confirmation. Radiographic diagnosis requires the surgeon to be fully aware of the plethora of unusual Meckel cave lesions that mimic benign tumors when they are malignant, inflammatory, or infectious and in need of a completely different and often timely intervention. When such a diagnosis is considered, it behooves the surgeon and benefits the patient to have a percutaneous biopsy technique available. OBJECTIVE: To use our recent experience with a patient with idiopathic inflammatory sensory neuropathy and another with Meckel cave lymphoma to review the management of tumors of the Meckel cave. METHODS: The technique of percutaneous biopsy of Meckel cave tumors through the foramen ovale with biopsy needles is detailed. CONCLUSION: Obtaining tissue biopsy percutaneously prevents patients with Meckel cave tumors best treated with nonsurgical management from undergoing open surgical resection with its concomitant morbidity.
Nonperturbative effective potential for lambdaphi$sup 4$ theory in the many- field limit

A $\ensuremath{\lambda}{\ensuremath{\varphi}}^{4}$ theory of self-interacting boson fields with $\mathrm{O}(N)$ symmetry is considered. A nonperturbative method is developed to compute the effective potential, which becomes exact in the large-$N$ limit. The stability of the vacuum and possible spontaneous symmetry breakdown of the theory are studied in this limit. The existence of a local mimimum requires $0l1+{(N\ensuremath{\lambda})}^{\ensuremath{-}1}96{\ensuremath{\pi}}^{2}$, which may be either a true bound or an indication of the breakdown of the ${N}^{\ensuremath{-}1}$ expansion. The function $\ensuremath{\beta}(\ensuremath{\lambda})$ that appears in the Callan-Symanzik equations is calculated in the large-$N$ limit of the massless theory without reference to a perturbation expansion in $\ensuremath{\lambda}$. It is observed that the presence of a nontrivial zero of $\ensuremath{\beta}(\ensuremath{\lambda})$ is a necessary condition for a spontaneously broken symmetry in the massless theory. On this basis, it is shown that this $\ensuremath{\beta}(\ensuremath{\lambda})$ is unlikely to have a nontrivial zero. The leading-logarithm approximation to the effective potential is discussed within the above framework.