cssi/SciSciGPT-SciSciNet huggingface dataset:
Chapter 1 Metal—molecule—semiconductor junctions:An ab initio analysis

Publisher Summary This chapter presents an ab initio analysis of metal–molecule–semiconductor junctions. The density functional theory (DFT) of quantum-chemistry is utilized to determine the electronic properties of molecules. A mathematical formalism based on the Green function (GF) is used to account for the effect of the contacts on the molecule keeping the realistic chemical nature of the sandwiched molecule. The DFT–GF formalism is used to calculate the conductance through metal–nitroOPE–phenylene–ethynylene (OPE)–metal junctions in several charge and conformational states. Two different metallic materials are evaluated: the commonly used gold and the promising carbon nanotube (CNT). The discrete electronic states of an isolate molecule are obtained by solving the Schrodinger equation. When the molecule is adsorbed on a contact tip, the continuous electronic states of bulk material modify the discrete electronic states of the molecule. The electronic properties of a molecular system can be calculated from its auxiliary wavefunction, which is built as a determinant of molecular orbitals (MOs).
Optimization of continuous heterogeneous models

A heterogeneous model consists of a solid model and a number of spatially distributed material attributes. Much progress has been made in developing methods for construction, design, and editing of such models. We consider the problem of optimization of a heterogeneous model, and show that its representation by a continuous function defined over a constructively represented domain naturally leads to simple and effective optimization procedures. Using minimum compliance optimization problem as an example, we show that the design sensitivities are directly obtainable in terms of material and geometric parameters, which can be used in any standard gradient-based optimization procedures. The proposed approach allows both local control of the material properties and global control of geometric variations, and can be used with many existing techniques for material modeling. Numerical experiments are given to demonstrate these representational advantages.
Influence of micronutrient and phoshorous levels and chelator to iron ratio on growth, chlorosis, and nutrition of Vaccinium ashei reade and V. elliottii chapman

Abstract ‘Tifblue’ (V. ashei Reade) and US 280 (V. elliotti Chapman) blueberry plants were exposed to 2×2×2 factorial treatments of high and low phosphate and micronutrients (Cu, Zn, Mn, and B) and excess or stoichiometric concentrations of a chelator (EDDHA) added to Fe(NO3)3 in pH 6.8 solution cultures. Phosphorous was applied at 20 (low) or 400 (high) μM levels, micronutrients at low or high levels and either a 1:1 or 10:1 ratio of chelator to Fe concentrations. Excess chelator in the nutrient solution always increased the severity of chlorosis except for US 280 plants grown under low P and stoichiometric chelator where neither micronutrient level resulted in chlorosis. Increased P concentration usually resulted in more severe chlorosis except for ‘Tifblue’ plants grown under low micronutrients and stoichiometric chelator where chlorosis did not develop with either P level. ‘Tifblue’ and US 280 differed in there response to excess solution Cu levels. Unlike highbush blueberries (V. corymbosum L.), thes...
Using word similarity to eradicate junk emails

Emails are one of the most commonly used modern communication media these days; however, unsolicited emails obstruct this otherwise fast and convenient technology for information exchange and jeopardize the continuity of this popular communication tool. Waste of valuable resources and time and exposure to offensive content are only a few of the problems that arise as a result of junk emails. In addition, the monetary cost of processing junk emails reaches billions of dollars per year and is absorbed by public users and Internet service providers. Even though there has been extensive work in the past dedicated to eradicate junk emails, none of the existing junk email detection approaches has been highly successful in solving these problems, since spammers have been able to infiltrate existing detection techniques. In this paper, we present a new tool, JunEX, which relies on the content similarity of emails to eradicate junk emails. JunEX compares each incoming email to a core of emails marked as junk by each individual user to identify unwanted emails while reducing the number of legitimate emails treated as junk, which is critical. Conducted experiments on JunEX verify its high accuracy.
Assessment of left ventricular function by the midwall fractional shortening/end-systolic stress relation in human hypertension

Objectives. This study examined left ventricular performance in relatively unselected hypertensive patients by use of physiologically appropriate midwall shortening/end-systolic stress relations. Background. Supranormal left ventricular function has been reported in hypertensive patients, possibly due to an artifact of mismatching endocardial rather than midwall fractional shortening to mean left ventricular end-systolic stress. Methods. Samples of 474 hypertensive patients (150 women, 324 men) and 140 normal subjects (68 women, 72 men) were drawn from a large urban employed population. The inverse relations (p < 0.0001) of both echocardiographic endocardial and midwall fractional shortening to end-systolic stress in normal subjects were used to calculate the ratios of observed to predicted endocardial and midwall fractional shortening in hypertensive patients. Midwall shortening was calculated from an elliptic model, taking into account the epicardial migration of the midwall during systole. Results. Use of midwall fractional shortening in hypertensive patients reduced the proportion of patients with function above the 95th percentile of normal from 22% to 4% (p < 0.0001) and fractional shortening as a percent of predicted from 107% (p < 0.001 vs. 100% in normotensive control subjects) to 95% (p < 0.0001; p < 0.001 vs. 101% in normotensive control subjects). Midwall shortening was below the 5th percentile of normal in 16% of hypertensive patients instead of 2% with endocardial shortening (p < 0.0001): They tended to be older than other hypertensive patients and had concentric left ventricular hypertrophy. Among hypertensive patients, these with concentric left ventricular hypertrophy or remodeling had reduced midwall shortening as a percent of predicted from end-systolic stress (p < 0.0001). Conclusions. Use of the physiologically more appropriate mid-wall shortening/end-systolic stress relation 1) markedly reduces the proportion of hypertensive subjects identified as having high endocardial left ventricular functions; and 2) identifies a substantial subgroup of patients with reduced left ventricular function who have concentric geometry of the left ventricle, a pattern associated with high cardiovascular risk.
Efficient allocation of resources to prevent HIV infection among injection drug users: the Prevention Point Philadelphia (PPP) needle exchange program

The objective of this study is to determine the allocation of resources within a multi-site needle exchange program (NEP) that achieves the largest possible reduction in new HIV infections at minimum cost. We present a model that relates the number of injection drug user (IDU) clients and the number of syringes exchanged per client to both the costs of the NEP and the expected reduction in HIV infections per unit time. We show that cost-effective allocation within a multi-site NEP requires that sites be located where the density of IDUs is highest, and that the number of syringes exchanged per client be equal across sites. We apply these optimal allocation rules to a specific multi-site needle exchange program, Prevention Point Philadelphia (PPP). This NEP, we find, needs to add 2 or 3 new sites in neighborhoods with the highest density of IDU AIDS cases, and to increase its total IDU client base by about 28%, from approximately 6400 to 8200 IDU clients. The case-study NEP also needs to increase its hours of operation at two existing sites, where the number of needles distributed per client is currently sub-optimal, by 50%. At the optimal allocation, the estimated cost per case of HIV averted would be $2800 (range $2300–$4200). Such a favorable cost-effectiveness ratio derives primarily from PPP's low marginal costs per distributed needle. Copyright © 2005 John Wiley & Sons, Ltd.
On the symmetry of the Smith normal form for (υ, k, λ) designs

It is shown in this paper (Theorems 5, 6, and 7) that ifS1,S2,Sv are the invariant factors of the incidence matrix for a (υ, k, λ) design with k and λ relatively prime, then
The reversible carbamate, (-)physostigmine, reduces the size of synaptic end plate lesions induced by sarin, an irreversible organophosphate

Pretreatment of rats with atropine and the reversible esterase inhibitor physostigmine [-)PHY), prior to injection of a lethal dose of the irreversible organophosphate sarin (0.13 mg/kg), protects 100% of the animals from lethality. We have used quantitative light and qualitative electron microscopy to show that damage to the end plate region of voluntary muscles is also strikingly limited by the same pretreatment. Drug effects on soleus motor end plates detectable 1 hr after treatment were (1) a single sublethal dose of sarin (0.08 mg/kg) produced large, blistered, and severely disrupted subjucntional regions. Damage extended from the end plate, in the form of myofiber necrosis and subsequent phagocytosis; (2) (-)PHY (0.1 mg/kg) itself had a selective effect in inducing irregularities of the subjunctional sarcomere band without any gross vacuolization; (3) the morphometric analysis done with light microscopy indicated that the combination of atropine (0.5 mg/kg) and (-)PHY (0.1 mg/kg) prior to a lethal dose of sarin (0.13 mg/kg) offered 86% reduction in the average area of the lesions, relative to the dimensions of damage induced by atropine/sarin alone. In most lesions induced by (-)PHY, recognizable changes were markedly less severe in degree and extent than those seen in sarin myopathy; there were few instances of extensive muscle damage and myofiber necrosis. The relationship of the (-)PHY dose to the level of protection against sarin suggested that (-)PHY pretreatment almost completely prevents the characteristic sarin-induced myopathy and, instead, imposes the characteristic PHY-induced subjunctional swelling. In all three experimental groups examined, the myopathic changes located extrajuctionally were reversible. The mechanism by which (-)PHY acts as a protective agent is discussed.
Pink Bollworm (Lepidoptera: Gelechiidae): Point Source Density and Its Relationship to Efficacy in Attracticide Formulations of Gossyplure

Tests with pink bollworm, Pecttnophora gossypiella (Saunders), were done to determine the effects of point source emission rates of gossyplure and the effects of density of point sources on the ability of male pink bollworm to orient to individual point sources within a mating disruption system. Results showed that, although a significantly greater percentage of available point sources were contacted by males in lower density Nomate pheromone applications (1, 2, or 4 fibers per m2 in wind tunnels and 0.012, 0.025, and 0.05 fibers per m2 in small plots), higher density treatments (16 fibers per m2 in wind tunnels and 1 fiber per m2 in small plots) caused significantly higher mortality in male populations as a result of increased contact between males and point sources. Samples from an aerial application of three densities of Hereon Disrupt flakes on 1.3-ha plots at 11,856, 23,712, and 47,424 flakes per ha indicated that plots treated with 11,856 flakes per ha had a significantly higher percentage (52.1) of the sampled flakes with moth scales than did plots treated with 23,712 (39.2%) and 47,424 (22.0%) flakes per ha. However, projecting the number of male! flake encounters based on the percentage of sampled flakes with moth scales from the three rates indicated that the high-density rate (47,242) received 10,434 male encounters compared with 9,295 and 6,177 encounters by males to flakes in plots treated with 23,712 and 11,856 flakes per ha. These data suggest that, within the density and emission ranges examined, synthetic sources did not cause adaptation or habituation. Maximum male response to point sources occurred at the highest point source density examined.
Conformational transitions of the lac repressor from Escherichia coli.

Temperature-jump studies of the lac repressor were performed monitoring the intrinsic tryptophan fluorescence of the protein. A single relaxation process with a time constant of 1·36×104 s−1 was observed for lac repressor solutions at pH 7·5 in the absence of inducer. The relaxation time is independent of the concentration of lac repressor indicating a conformational transition between two states of the repressor (R*гR). Although the binding of an inducer, isopropyl-β- d -thiogalactoside, is too slow (as shown by stopped-flow studies) to influence the rate of the rapid interconversion between these two states of the lac repressor, the relaxation amplitude decreases with increasing IPTG † concentration. The rate of this conformational transition is altered by protonation of the repressor. Temperature-jump data obtained for lac repressor at various pH values can be analyzed in terms of a concerted mechanism in which a proton binds preferentially to one of the two states of lac repressor (R). We propose that IPTG also binds selectively to the R state. This is consistent with our observation that addition of 10−3 m -IPTG shifts the pK of a specific group of amino acid residues in the lac repressor. Furthermore, the mechanism provides satisfactory explanations for previous reports that the bimolecular rate-constant for the IPTG-lac repressor interaction is extremely low and that the inducer binding may exhibit various degrees of co-operativity at different pH values. Thus the allosteric transition of lac repressor effected by proton and inducer may play a significant role in the regulation of lac transcription.
Fluorescent probes attached to Cys 35 or Cys 84 in cardiac troponin C are differentially sensitive to Ca2+-dependent events in vitro and in situ

The goal of the current study was to generate recombinant cTnC proteins with single Cys residues as sites for attachment of fluorescent probes that can distinguish between the structural effects of myosin cross bridges and direct Ca2+ binding to cTnC (cardiac and slow skeletal troponin C) in skinned fibers. We anticipated that cTnC proteins which retain the endogenous Cys 35 (cTnC(C35)) or Cys 84 (cTnC(C84)) would provide fluorescent probes with distinct microenvironments, since these residues are on opposite sides of the globular regulatory domain. In vitro experiments that showed IAANS (2-(4'-(iodoacetamido)anilino)naphthalene-6-sulfonic acid) coupled to Cys 35 can induce unwanted structural perturbations as evidenced by a decreased affinity of site II for Ca2+ when IAANS-labeled cTnC(C35) is bound to cTnI. Important structural features involving Cys 35 in the inactive site I are suggested by a Ca(2+)-dependent increase in reactivity of Cys 35 with sulfhydryl specific reagents when cTnC(C35) is associated with cTnI. These characteristics are not seen for cTnC(C84). When incorporated in situ into skinned cardiac muscle fibers, native cTnC with IAANS bound to both Cys 35 and Cys 84 showed a pCa50 of fluorescence which preceded that of force, while the pCa50 values of both force and fluorescence were coincident for IAANS-labeled cTnC(C84). Disruption of force-producing myosin cross bridges had no effect on the pCa50 of fluorescence for IAANS-labeled cTnC(C84), but induced a rightward shift in the pCa50 of fluorescence for IAANS-labeled native cTnC. These data can be interpreted to indicate that cTnC with IAANS bound to both Cys 35 and C84 senses either myosin cross bridges or direct Ca2+ binding and myosin-induced cooperativity, while IAANS bound to Cys 84 alone senses conformations that are tightly coupled with force generation.
Calcium-binding protein biosynthesis in the rat: regulation by calcium and 1,25-dihydroxyvitamin D3.

Abstract Vitamin D-replete rats on high or low calcium diets received by intraperitoneal injection varying doses (62.5–750 ng/animal) of 1,25-dihydroxyvitamin D 3 (1,25-(OH) 2 -D 3 ). The animals on the high calcium diet showed a progressive, dose-dependent response to the vitamin D metabolite; their duodenal levels of the cytosolic calcium-binding protein increased from about 50 nmol Ca bound /g mucosa to nearly 100 nmol Ca bound /g mucosa. The animals on the low calcium diet, whose calcium-binding protein base levels were about 100 nmol Ca bound /g mucosa, showed no response to the metabolite and their calcium-binding protein levels remained unchanged even with high doses of 1,25-(OH) 2 -D 3 . Vitamin D-deficient animals on a high calcium diet from weaning gave the same quantitative response to progressive doses of 1,25-(OH) 2 -D 3 as the replete animals, but the time and rate at which calcium-binding protein reached its maximum level in the intestine differed in the two groups. In the replete animals the calcium-binding protein response to 1,25-(OH) 2 -D 3 was completed by 1 h after treatment, whereas in the deficient rats the maximum response was not attained until 16–20 h. Plasma calcium responses to exogenous 1,25-(OH) 2 -D 3 occurred before the calcium-binding protein response in D-deficient animals and after in replete animals. The plasma calcium response therefore is not an index of the molecular response to vitamin D. It is concluded that the extent of the calcium-binding protein response to exogenous 1,25-(OH) 2 -D 3 is a function of the calcium status of the D-replete animal and that there exists an upper limit of this response. The time and rate of the calcium-binding protein response, on the other hand, depend on prior vitamin D status and may reflect a post-transcriptional as well as a transcriptional role of the metabolite in the intestinal cell.
Prospective Study of Oral Contraceptives and Hypertension Among Women in the United States

Background Oral contraceptives induce hypertension in approximately 5% of users of high-dose pills that contain at least 50 μg estrogen and 1 to 4 mg progestin, and small increases in blood pressure have been reported even among users of modern low-dose formulations. However, neither the responsible hormone in the oral contraceptive nor particular subgroups of women who might be susceptible to the hypertensive effect of oral contraceptives have been identified. Methods and Results In a prospective cohort study in the United States, 68 297 female nurses aged 25 to 42 years and free of diagnosed hypertension, diabetes, coronary heart disease, stroke, and cancer at baseline were followed up for 4 years. During 231 006 person-years of follow-up, 1567 incident cases of hypertension were diagnosed. Compared with women who had never used oral contraceptives, the age-adjusted relative risk was 1.5 (95% CI=1.2 to 1.8) for current use and 1.1 (95% CI=0.9 to 1.2) for past use. After adjustment for age, body mass index, cigarette smoking, family history of hypertension, parity, physical activity, alcohol intake, and ethnicity, current users of oral contraceptives had an increased risk of development of hypertension (RR=1.8; 95% CI=1.5 to 2.3) compared with women who had never used them. The multivariate relative risk for past users was 1.2 (95% CI=1.0 to 1.4). There were no important modifying effects of age, family history of hypertension, ethnicity, or body mass index. Conclusions Current users of oral contraceptives had a significant, moderately increased risk of hypertension. However, among this group, only 41.5 cases per 10 000 person-years could be attributed to oral contraceptive use. Risk decreased quickly with cessation of oral contraceptives, and past users appeared to have only a slightly increased risk.
Intermediate range order in computer modeled a-As2S3

Abstract Features of intermediate range order [IRO] are important to the understanding of the properties of amorphous semiconductors. Specifically with respect to a-As2S3, photodarkening is an effect related to a change in the IRO of the glass. Unfortunately, IRO represents a relatively inaccessable experimental regime because of disordered broadening and a lack of symmetries in the glass. Modeling can be used to examine the IRO insofar as a realistic model can be constructed that can be both checked against existing experiments and examined for features of IRO. We chose to build models of a-As2S3 in order to study this order. We built our models such that they agree with all conceivable experimental results. With this agreement, we feel that we will have modeled the glassy state of the compound as closely as experimental comparison will allow. Models were generated with a program which placed atoms in the model and relaxed them to their lowest potential energy. Since the models were generated by a computer they could be made arbitrarily large and thus we could avoid finite size problems of other models. We have discovered order with respect to dihedral angle statistics and discuss this order in terms of local helical units. Furthermore, we have generated computer-graphic pictures of our models in order to examine subtler features of structure that visual inspection reveals and that other analyses cannot define.
Effect of tamoxifen on sex steroid concentrations in chicken ovarian follicles

The aim of the present investigation was to study the effect of tamoxifen (TAM), an oestrogen receptor antagonist, on the concentrations of sex hormones in chicken ovarian follicles. The experiment was carried out on Hy-line hens which were randomly divided into two groups (control and experimental). TAM was given at a dose of 4 mg/hen (per os) at first once a day for 7 consecutive days, and subsequently four times a day for the subsequent 6 days. Control hens received placebo. Birds were killed on the day after the last TAM treatment. From the dissected ovaries the following compartments were isolated: stroma with follicles < 1 mm, white non-hierarchical (1–4 mm and 4–8 mm) and yellow hierarchical follicles (F6–F1; 18–35 mm). The concentrations of the sex steroids progesterone (P4), testosterone (T) and oestradiol (E2) in the ovarian follicles were determined by radioimmunoassay. In the TAM-treated group, a gradual decrease in egg-laying rate was observed from the 4th day of the experiment. Eventually, egg laying stopped entirely on the 12th day of the experiment. TAM significantly decreased the weight of the ovary and affected the sex hormone concentrations in the ovarian follicles. Following TAM treatment (1) a significant increase in E2 and T concentrations in the stroma, white follicles and the F4 and F1 follicles, (2) a significant decrease in E2 and T concentrations in the F2 follicle, and (3) a significant decline of P4 in the F4 to F1 follicles were observed. The results indicate that the blockade of oestrogen receptors by TAM significantly modulates the process of chicken ovarian steroidogenesis.
Microstructural analysis and tensile properties of thick copper and nickel sputter deposits

Abstract Ultrafine-grained microstructures were formed in Cu and Ni sputter deposits 0.5-3 mm thick for a microstructure-mechanical property investigation. Grain sizes were as low as 0.06 μm in Cu and 0.031 μm in Ni. Columnar grains and twins were observed in transmission electron micrographs of both Cu and Ni deposits, but equiaxed structures either alone or mixed with columnar grains were also observed. The statistical distribution of twin spacings in the columnar grains was investigated and was found to follow a random distribution, which correlated well with low twin pair interaction energies calculated from pseudopotential theory. Tensile stress-strain data were obtained from the Cu and Ni sputter deposits for the correlation of yield strength with grain size. The small grain sizes produced in Cu permitted the well-known yield strength-reciprocal square-root grain size relationship to be extended to grain sizes 50 times smaller than previously investigated. Yield strengths for Ni were lower than expected from a linear extrapolation of previous data on non-sputtered Ni.
Nutritional stress due to habitat loss may explain recent honeybee colony collapses.

In spite of the tremendous public interest in the recent large honeybee losses attributed to colony collapse disorder, there is still no definitive explanation for the phenomenon. With the hypothesis that nutritional stress due to habitat loss has played an important role in honeybee colony collapse, I analyze the land use data in United States to show that the colony loss suffered by each state is significantly predicted by the extent of its open land relative to its developed land area. I provide further support for this hypothesis by showing that states with the largest areas of open land have a significantly higher honey yield on a per colony basis. I discuss how increasing loss of foraging resources could be synergistically acting with emerging diseases to stress honeybee populations and the importance therefore for preserving natural areas that act as important pollinator habitats.
The metabolic gradients of vertebrate embryos. II. The brook lamprey

Disintegration in killing agents was studied throughout development. In the unfertilized egg and cleavage stages the death gradient runs from animal to vegetal pole. In the late blastula stage the future dorsal surface and future point of gastrulation show heightened susceptibility. The gastrula has a gradient from anterior to posterior end along its dorsal surface, with a slight reverse gradient around the blastopore; lateral and ventral regions are least susceptible. Before and after the appearance of the neural groove, the dorsal surface shows increased susceptibility with gradient in it from anterior to posterior end. The neural tube is highly susceptible, with a death gradient from anterior to posterior end and a slight reverse gradient at its posterior end. During late stages and in the larva the double gradient is present; death begins at the two ends and progresses backward from head, forward from anus; from the former most rapidly. The least susceptible place is near the posterior end. The posterior reverse gradient is less developed in the lamprey than in other vertebrate embryos, due, probably, to its lack of a tail bud. Assuming that death differences indicate differences in rate of activity, it appears that such differences in activity may be causes and not results of developmental processes, for the development of certain parts (dorsal surface, blastopore, central nervous system) is indicated by heightened activity before it is evident morphologically.
Rewards for Good Marketing.

Have you developed and implemented an original marketing strategy/program that has effectively brought patrons onto your Web site, into your library, or through to your interactive virtual services...
Outdoor testing of nonceramic insulators

Nonceramic insulators (NCIs) are varied in design, but all essentially consist of three components: a resin bonded glass-fibre rod or tube; covered by a polymer weather shed; and metal end-fittings. Composite (nonceramic) long-rod insulators have been installed on overhead lines as replacements for conventional porcelain or glass cap-and-pin insulators for about twenty years. Unfortunately, problems associated with the early designs had cast doubts on the long-term electrical and mechanical performance of this type of insulator. Hence, composite insulators require two acceptance criteria, (i) suitable electrical properties, including insulation capability, and resistance to tracking or erosion during surface electrical discharges, and (ii) reliable long-term mechanical performance. Outdoor testing of NCIs is required to establish appropriate acceptance criteria, and guidelines for their application. The author discusses the electrical and mechanical properties required by NCIs and then discusses type approval tests being undertaken at the Dungeness Insulator Testing Station. (4 pages)
Cutaneous Mycobacterium haemophilum infection in iatrogenically immunocompromised patients without transplantation

Cutaneous Mycobacterium haemophilum infections are most often the result of HIV or transplantation-associated immunosuppression. Rarely, M haemophilum may infect healthy patients or iatrogenically immunosuppressed patients without transplantation. We herein report two cases of cutaneous M haemophilum infection in HIV-negative patients without transplantation undergoing iatrogenic immunosuppression. Our cases and a literature review highlight the various clinical contexts in which M haemophilum may arise in this patient population. Accordingly, we emphasize that a high index of suspicion is needed for diagnosis, which ultimately relies on skin biopsy, histopathologic examination, and culture.
Culture & Development: Lessons learnt from the Post-Election Violence in Kenya

Culture encompasses, without being reducible to, values and norms that underpin a people's way of thinking and doing things. Development on the other hand can be analyzed as any progression toward a goal. If this is the case then we instantly appreciate the nexus between the two concepts. A community will have a certain perception of the world (culture) and how it would like to transform that world to its own good (development) through various initiatives and processes. Some scholars argue that development should be anchored in a people's culture. It cannot be brought to them from the outside because that would be someone else' idea of development (Boukary 2003). Others might argue that development can be introduced from outside to create awareness, then the culture of the people accommodates and domesticates it. In market studies terms, development should be a felt need by a community to develop a product in the case of the first theory or a product introduced into the market that people learn to appreciate in the latter scenario. We believe the two models are complementary. This paper discusses the concepts of culture and development with respect to the post-election violence in Kenya that left 1,200 people dead and another 400,000 displaced from their homes. We recast the violence within the wider context of the history, cultural diversity and economics of Kenya. How can an island of peace for 45 years plunge into senseless killings overnight that negate a sound development record of 7% GDP growth? Key words : culture, development, violence, ethnicity, values
Computer aided instruction in speech science

Abstract The use of a computer based speech analysis and synthesis system for elementary instruction in speech science is described. System organization and the development of an interactive command language are covered. This approach, in which the student actively uses the computer, is contrasted with instructional use in which the computer determines the students behavior.
The effect of anions on the interaction of pyridoxal phosphate with glutamate apodecarboxylase.

Abstract The rate of binding of pyridoxal phosphate to Escherichia coli glutamate apodecarboxylase was measured by absorption spectroscopy and enzyme activity in pyridine buffers containing a variety of anions. The change in absorbance at 428 nm using 20 μ m , apoenzyme and 50 μ m pyridoxal-P follows second-order kinetics. The apparent second-order rate constants obtained vary according to the anion present. Halides enhance the rate of binding in the order fluoride > chloride > bromide. Sulfate is a very potent inhibitor of binding. Phosphate, its methyl, ethyl, and phenyl esters, and pyrophosphate also inhibit pyridoxal-P binding to the apoenzyme. Monocarboxylic acids inhibit the rate of binding of coenzyme to apoenzyme in 50 m m pyridine-chloride, pH 4.6. Acetate is the best inhibitor, and there is a progressive decrease in inhibition with increasing chain length up to heptanoate. Multiple inhibition studies show that phosphate, sulfate, and acetate as inhibitors of pyridoxal-P binding are all competing for the same site. This anion-binding site appears to bind divalent anions tighter than monovalent anions and is sterically hindered for binding long chain carboxylic acids and phenylphosphate. Chloride, an activator of coenzyme binding, and sulfate, an inhibitor of binding, have no effect on the size of glutamate apodecarboxylase as determined by gel filtration. The holoenzyme and the apoenzyme both have a Stokes radius of 57 A and a molecular weight of approximately 310,000 in 50 m m pyridine-chloride or 50 m m pyridine-ulfate, pH 4.6. However, chloride, nitrate, and sulfate do have different effects on the heat denaturation of the apoenzyme.
Spectroscopic studies on heme d in the visible and infrared.

Abstract Heme d has been isolated from the terminal oxidase complex of Escherichia coli strain MR43L F152 and purified by high-pressure liquid chromatography. The infrared spectrum indicated that carbonyls in the chlorin skeleton of this isolated heme existed as carboxylic acids. Earlier work on the iron-free chlorin had demonstrated the presence of a spirolactone substituent. This may have arisen from a cyclization reaction from a dicarboxylic acid, diol precursor. Although the free heme in extracts can exist as a diol, this does not prove that the diol as such is the precise form in the enzyme complex. Visible and fluorescence spectra are reported for a variety of derivatives and complexes of heme d to establish a spectral library that may be used to prove the presence of this structure in other enzymes or cells. Association constants have been measured for complexes of heme d with cyanide, imidazole, and pyridine and are contrasted to available data for protoheme.
Langston Hughes' message for the black masses

Langston Hughes, perhaps the leading Black literary figure of this century, had barely entered the mainstream of American literature at his death in 1967. Hughes claimed himself a social poet who wrote about the problems of Black people. He did so for his entire life, but for twenty‐two years he used the medium of the newspaper and a short story format to present his message to an audience. This essay explores the Simple columns, which were published in the Chicago Defender, for the messages, insights, and methods of resolving the problem of being Black in a White America.
Z-axis high-contrast resolution for multi- vs. single-slice CT

One aspect of image quality that should be considered when migrating scan protocols from single-slice helical CT (SSCT) to multi-slice CT (MSCT) is z-axis high-contrast resolution. The aim of this study was to compare z-axis high-contrast resolution of MSCT with that of a similarly designed SSCT for various combinations of slice thickness and pitch. A point response phantom was used to acquire slice sensitivity profiles (SSPs) and calculate z-axis resolution (10% of MTF). Additionally, a resolution pattern phantom was used to subjectively evaluate limiting z-axis resolution. Both analytical and subjective results revealed that the SSCT had higher z-axis resolution than the MSCT for nominal 5 mm slice thickness (at comparable pitches). However, for nominal 10 mm slice thickness the MSCT demonstrated z-axis resolution that was comparable or superior to SSCT. Additionally, notable differences in the shape of the SSP for axial scans were observed on the MSCT unit due to the presence of detector septa. Several conclusions can be drawn from these results including: (1) z-axis resolution is not necessarily 'better' for MSCT and should be evaluated prior to transferring scan protocols from single- to multi-slice CT, and (2) a simple acrylic plate resolution phantom may be used to quickly and effectively evaluate z-axis resolution.
Bik and Bak Induce Apoptosis Downstream of CrmA but Upstream of Inhibitor of Apoptosis

Recent studies have identified a number of cell death pathway components. In this study, we describe the role that two such components, Bik and Bak, play in initiating the apoptotic program. These Bcl-2 family members engage the death pathway downstream of the block imposed by the serpin CrmA, but upstream of the block initiated by cellular inhibitors of apoptosis, which are a family of molecules characterized by a conserved baculovirus inhibitor of apoptosis repeat motif. Distal death pathway components activated by Bik and Bak are similar to those activated by the CD-95 (Fas/Apo1) and tumor necrosis factor death receptors.
The role of external representation in the writing process: implications for the design of hypertext-based writing tools

The long-range goal of the research reported here is to study the role of hypertext-based external representations in augmenting performance on a cognitively complex task, in particular, on a synthesis writing task. The production of a written synthesis is a challenging task that requires managing large amounts of information over an extended period of time. Thus, synthesis writing is a task that is well-suited for testing the potential of hypertext technologies to support work on complex tasks.From a case study of experts and novices, we have developed a theory of the cognitive processes involved in producing a written synthesis. We have also developed a preliminary theory of the role of external representations in the writing process. We have drawn upon these two theories to design several hypertext-based external representations that we believe will augment writers' performance on a written synthesis task. The hypertext-based applications include a general graph object and a table object; these objects form the foundation for a set of specialized tools to support synthesis writing, namely, a summary graph, synthesis grid and synthesis tree.
On the inter-ring separation of the lowest excited and ionized states of [2.2]paracyclophane

Abstract The geometries of the ground state, the four lowest excited states and the lowest triplet state of [2.2] paracyclophane are obtained from SCF (STO-3G) calculations. The calculated structure for the ground state, 1 A g , is in very good agreement with experiment. The inter-ring separations in the lowest triplet (B 3g ) and singlet (B 2g ) states are calculated to be 0.20 and 0.31 A shorter than the same distance in the ground state, respectively. This observation is used to explain the large red-shift observed in the phosphorescence and fluorescence spectra. The inter-ring separation in the ground state radical cation has also been calculated and it is used in the comparison of the absorption spectrum of the cation with the photoelectron spectrum of neutral [2.2] paracyclophane.
Multiband anomaly detection using signal subspace processing

In the past, many researchers have approached the "Hyperspectral-imagery-anomaly-detection" problem from the point of view of classical detection theory. This perspective has resulted in the development of algorithms like RX (Reed-Xiaoli) and the application of processing techniques like PCA (Principal Component Analysis) and ICA (Independent Component Analysis--algorithms and techniques that are based primarily on statistical and probabilistic considerations. In this paper we describe a new anomaly detection paradigm based on an adaptive filtering strategy known as "signal subspace processing". The signal-subspace-processing (SSP) techniques on which our algorithm is based have yielded solutions to a wide range of problems in the past (e.g. sensor calibration, target detection, and change detection). These earlier applications, however, utilized SSP to relate reference and test signals that were collected at different times. For our current application, we formulate an approach that relates signals from one spatial region in a hyperspectral image to those from a nearby spatial region in the same image. The motivation and development of the technique are described in detail throughout the course of the paper. We begin by developing the signal subspace processing anomaly detector (SSPAD) and proceed to illustrate how it arises naturally from the adaptive filtering formulation. We then compare the algorithm with existing anomaly-detection schemes, noting similarities and differences. Finally, we apply both the SSPAD and various existing anomaly detectors to a hyperspectral data set and compare the results via receiver operating characteristic (ROC) curves.
The development of the folia in the human cerebellar vermis

The development of the folial patterns of the human cerebellar vermis has been studied in 44 mid sagittal sections of fetuses (14 weeks gestational age to term), infants (one to three months) and adults. The differentiation of each of the lobules of the vermis has been plotted as a function of age. The gestational age at which each lobule has attained half the adult average number of folia has been determined and varies between 24 and 37 weeks; the more anterior and posterior vermian lobules reach this half-way point first even though the largest lobules (culmen, declive and pyramis) form more folia per unit time. Thus, different criteria may be used to evaluate growth rates and yield different conclusions concerning the validity of the concept that ontogeny recapitulates phylogeny. The adult numbers of folia are not attained until more than two months after birth. The normative data reported in this study provide a baseline for comparison with other species or with abnormal developmental patterns in autopsy specimens of any fetal or post-natal age.
Use of photoproteins for in-vivo functional imaging

The relative opacity of mammalian tissue permits the transmission of light from internal biological light sources in small laboratory animals. As such internally expressed bioluminescence can be detected externally revealing spatiotemporal information about tagged biological functions. Enzymes that emit light, photoproteins, have been characterized photoproteins have been used as reporters in a variety of in vitro and ex vivo assays and are now being employed as sources of internal biological light that can be eternally monitored in living animals. Using this approach, spatiotemporal changes in patterns of gene expression, infectious disease and tumor cell growth can be revealed in real time. Monitoring light emissions from internal sources provides a powerful method for cellular and molecular analyses in living animals. This approach is particularly well suited for the evaluation of potential therapeutics including the efficacy of novel DNA-based therapies and vaccines.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Form Domains and Eigenfunction Expansions for Differential Equations with Eigenparameter Dependent Boundary Conditions

Form domains are characterized for regular 2n-th order differential equations subject to general self-adjoint boundary conditions depending afnely on the eigenparameter. Corresponding modes of convergence for eigenfunction expansions are studied, including uniform convergence of the rst n 1 derivatives.
The American Academy of Sleep Medicine Inter-scorer Reliability program: respiratory events

Study Objectives:The American Academy of Sleep Medicine (AASM) Inter-scorer Reliability program provides a unique opportunity to compare a large number of scorers with varied levels of experience t...
Rhinorrhea, cough and fatigue in patients taking sitagliptin

Sitagliptin is a dipeptidyl peptidase-4 (DPP IV, CD26) inhibitor indicated for treatment of Type II diabetes as a second line therapy after metformin. We report fifteen sitagliptin intolerant patients who developed anterior and posterior rhinorrhea, cough, dyspnea, and fatigue. Symptoms typically developed within 1 to 8 weeks of starting, and resolved within 1 week of stopping the drug. Peak expiratory flow rates increased 34% in 8 patients who stopped sitagliptin. Similar changes were found in 4 out of 5 persons who had confirmatory readministration. Chart review identified 17 patients who tolerated sitagliptin and had no symptomatic changes. The sitagliptin intolerant group had higher rates of clinically diagnosed allergic rhinitis (15/15 vs. 6/18; p = 0.00005), Fisher's Exact test) and angiotensin converting enzyme inhibitor - induced cough (6/13 vs. 1/18; p = 0.012). Nasal and inhaled glucocorticoids may control the underlying allergic inflammation and abrogate this new sitagliptin - induced pharmacological syndrome. Potential mucosal and central nervous system mechanisms include disruption of neuropeptides and/or cytokines that rely on DPP IV for activation or inactivation, and T cell dysfunction.
Gold(III) fluorosulfate as an initiator of the polymerization

Gold(III) fluorosulfate was shown to have potential for initiating the polymerization and graft copolymerization of tetrahydrofuran (THF) and similar monomers at room temperature. Addition to THF of either gold(III) fluorosulfate or of gold(III) fluorosulfate and acetyl chloride (a model for a reactive polymer backbone) led to high yields (60–70%) of polytetrahydrofuran. IR, NMR, HPLC, and other studies were used to determine the mechanism of initiation in each case. They showed that in the absence of halide, the gold salt led to hydrogen abstraction from THF and formation of protonic acid, which then initiated polymerization. In the presence of halide, concurrent initiation due to the formation of tertiary oxonium ion by acetylation occurred. Gold(III) chloride precipitated simultaneously.
A pulse-pileup correction procedure for rapid measurements of hydroxyl concentrations using picosecond time-resolved laser-induced fluorescence

The measurement of fluorescence lifetimes is important for determining minor-species concentrations in flames when using linear laser-induced fluorescence (LIF). Applications of LIF to turbulent flames require that the quenching rate coefficient be determined in less than ∼100 μs. Moreover, the measurement technique must be insensitive to the existence of relatively large backgrounds, such as occur from flame emission. To meet these goals, we have recently developed a rapid, gated photon-counting technique, termed LIFTIME. However, for ultimate application to turbulent time-series measurements, LIFTIME must be extended to photon count rates which unfortunately result in nonlinear discriminator operation. In this paper, a correction technique is derived to permit quantitative measurements of fluorescence lifetimes and concentrations at sampling rates up to 4 kHz. The technique was tested against liquid samples having a known lifetime and is further shown to reproduce previous hydroxyl concentration measurements in a series of laminar flames with total photon count rates of up to ∼35 million detected photoelectrons per second. The fluorescence lifetimes and hydroxyl concentrations are shown to be measured with ∼10% accuracy (68% confidence interval) for sampling times as low as 250 μs.
Competitors and fouling organisms in the hanging culture of the pacific oyster, crassostrea gigas (thunberg)

Generally speaking the “enemies”; of oysters can be divided ecologically into three classes: 1) “parasites”; which live within the body of the oyster and cause harm, 2) “competitors (fouling organisms)”; which occupy the same ecological niche as the oyster and cause harm indirectly by, contesting the available food and living space, 3) “predators”; which feed on the oyster. The sort of harm which can affect oysters differs widely with cultivation technique and habitat conditions. For instance, with the raft hanging method, long line method and other intensive cultivation practices which involve submersion in the sea, the harm from competitors such as Mytilus edulis gcdloprovincialis, tunicates and barnacles is most noticeable. On the other hand, with natural reproduction and sowing methods or the rack hanging method, in which the cultivation generally takes place in the littoral zone or on sea bottom, the most prevalent harm is caused by such bottom dwelling predators as drills (murices, naticids), sea st...