cssi/SciSciGPT-SciSciNet huggingface dataset:
Dipole and spin-dipole resonances in charge-exchange reactions on 12C.

The $^{12}\mathrm{C}$(n,p${)}^{12}$B reaction was studied using the white neutron source at the Los Alamos Meson Physics Facility/Weapon Neutron Research Center with a continuous incident neutron energy from 60 to 260 MeV. Double differential cross sections were measured in the angular range 11\ifmmode^\circ\else\textdegree\fi{}\ensuremath{\le}${\mathrm{\ensuremath{\theta}}}_{\mathrm{lab}}$\ensuremath{\le}37\ifmmode^\circ\else\textdegree\fi{}. Using the neutron time-of-flight facility at the Indiana University Cyclotron Facility, we also studied the $^{12}\mathrm{C}$(p,n${)}^{12}$N reaction at ${\mathit{E}}_{\mathit{p}}$=186 MeV and the $^{12}\mathrm{C}$(p\ensuremath{\rightarrow},n\ensuremath{\rightarrow}${)}^{12}$N reaction at ${\mathit{E}}_{\mathit{p}\ensuremath{\rightarrow}}$=160 and 186 MeV. Double differential cross sections were measured between ${\mathrm{\ensuremath{\theta}}}_{\mathrm{lab}}$=0\ifmmode^\circ\else\textdegree\fi{} and ${\mathrm{\ensuremath{\theta}}}_{\mathrm{lab}}$=50\ifmmode^\circ\else\textdegree\fi{} in 5\ifmmode^\circ\else\textdegree\fi{} steps. Spin observables ${\mathit{D}}_{\mathit{N}\mathit{N}}$, ${\mathit{A}}_{\mathit{Y}}$, and P were measured at ${\mathrm{\ensuremath{\theta}}}_{\mathrm{lab}}$=5\ifmmode^\circ\else\textdegree\fi{},9\ifmmode^\circ\else\textdegree\fi{},13\ifmmode^\circ\else\textdegree\fi{} with ${\mathit{E}}_{\mathit{p}\ensuremath{\rightarrow}}$=160 MeV and ${\mathrm{\ensuremath{\theta}}}_{\mathrm{lab}}$=15\ifmmode^\circ\else\textdegree\fi{},20\ifmmode^\circ\else\textdegree\fi{} with ${\mathit{E}}_{\mathit{p}\ensuremath{\rightarrow}}$=186 MeV. Angular distributions of differential cross section and spin observables for low-lying transitions in the residual nuclei are compared with disorted-wave impulse approximation (DWIA) calculations. A multipole decomposition analysis was performed to study the giant dipole and giant spin-dipole resonances. The contributions of the quasifree reaction in the giant resonance region was subtracted. The empirical results of energy distributions for dipole (\ensuremath{\Delta}L=1) transition are compared with DWIA calculations using nuclear structure information obtained with a conventional shell model and also with a random phase approximation.
Technology, power, and structure: Developing a model of the effects of automation on liberal arts college libraries

Abstract Based upon theories of organizational structure and power, especially the strategic contingencies theory of intraorganizational power, a model of organizational power and technology within liberal arts colleges is developed, tested, and modified. The model includes measures of subunit (library) power, environment, extent of automation, organizational structure, and bases of power. Data on 487 liberal arts college libraries collected from the 1982 HEGIS survey, the 1990 IPEDS survey, and two mailed questionnaires provided limited support for the proposed model of intraorganizational power. Changes in the amount of library automation caused changes in several of the bases of power of the libraries. Analyses of a modified model of intraorganizational power and technology showed that as automation and the environmental variables increased, subunit bases of power increased, and all of these directly increased library power. Thus, automation can be a change agent within organizations, causing changes in structure, in the bases of power, and in power itself.
Taste papillae of the blowfly

Each interpseudotracheal papilla on the oral surface of the labellum of the blowfly contains four bipolar neurons. An electrophysiological analysis has shown that one of these cells is a receptor which responds specifically to carbohydrates. The response consists of a rapid initial discharge which typically adapts to one-half maximum frequency in 300–400 msec. The response remains normal even in the presence of choline chloride (1.5–2.0 M), NaCl (0.01–2.0 M), and CaCl2 (0.01–1.0 M). The various sugars tested showed the following order of increasing effectiveness: sorbitol < sorbose < inositol < fucose < arabinose < glucose < sucrose < fructose. Mannose, a nutritive sugar, is non-stimulating. D-arabinose, an acceptable sugar, is more stimulating than L-arabinose, an unacceptable sugar. L-arabinose, in contrast to D-, also stimulates other neurons in the papilla. Another cell responds when the electrode contains salt or certain carbohydrates such as L-arabinose. It is believed that its activity initiates behavioral rejection of compounds. It does not exhibit a high initial discharge or adaptation but waxes and wanes randomly. Its response to monovalent and divalent cations is similar although the latter produces volleys of high frequency. Mechanical deformation causes an increase in frequency of a third spike. Mechanosensitive units may be classified by their responses into three classes: push, pull, or push-pull. No evidence for a water receptor was found.
Seasonal patterns of plant and soil water potential on an irregularly-flooded tidal marsh

Abstract Water potential ( ψ p ) of five plant species and soil water potential (ψ s ) in theie respective communities were measured before dawn once a week throughout the 1978 growing season on an irregularly flooded tidal marsh on the Rhode River of the Chesapeake Bay. The five species exhibited two different seasonal patterns of ψ p . Two species ( Scirpus olneyi Gray and Scirpus robustus Pursh) had pre-dawn ψ p ⩾ −5 bar throught the entire growing season; and three species ( Iva frutescens L., Spartina cynosuroides (L.) Roth and Panicum virgatum L.) had ψ p that ranged between −5 and −15 bar. Although there were consistent differences between the ψ s of the plant communities at 50 cm and within 10 cm of the marsh surface, these differences were small ( ψ s of all communities on the marsh was always higher than −8 bar. The correspondence between plant distribution, ψ p and ψ s was not as expected: species with the lowest ψ p were found in the communities having the highest ψ s .
Light Therapy for Insomnia in Older Adults

Exposure to bright light suppresses the production of melatonin and contributes to the regulation of the circadian rhythm. Because of environmental and medical conditions, older adults are less likely than younger adults to receive the prolonged, high intensity, daily bright light needed to promote a satisfactory sleep-wake cycle. The best available evidence for bright light therapy is in the management of seasonal affective disorder, which is relatively infrequent in the elderly population. For older adults with chronic insomnia, dementia, and nonseasonal depression, there is no consensus on the optimum treatment protocol for bright light therapy. However, in addition to sleep improvement, bright light therapy may be used to reduce unwanted behavioral and cognitive symptoms associated with dementia and depression in the elderly.
Post-reductionist protein science, or putting Humpty Dumpty back together again

In their native environments, proteins perform their biological roles in highly concentrated viscous solutions and in complex networks with numerous partners. Yet for many years, the normal practice has been to purify a protein of interest in order to characterize its structural and functional properties. In this Commentary, we discuss how protein scientists are now tackling the theoretical and methodological challenges of studying proteins in their physiological context.
Classification of environmentally induced genetic male sterile lines of rice based on their fertility responses to photoperiod and temperature

The use of environmentally induced genetic male sterile (EGMS) rice could alter the development of hybrid rice from a three-line system to a two-line system. It is critical for the utilization of EGMS rice to determine which are the main environmental factors influencing fertility changes. Fertility responses to photoperiod (P) and temperature (T) were studied in 101 EGMS rice lines under nine controlled regimes combining three photoperiods (15·0, 14·0 and 12·5 h)x three temperatures (30·1, 24·1 and 23·1 °C). According to the variance analysis of seed-setting data, 96% of the total EGMS lines studied could be divided into three types as follows: (1) photoperiod-sensitive genetic male sterility (PGMS) characterized statistically by significant (P < 0·05) P and P × T interaction effects but by a non-significant T effect on fertility, (2) thermosensitive genetic male sterility (TGMS) by a significant T effect, a non-significant P effect and by either a significant or a non-significant P × T interaction effect on fertility, and (3) photo-thermosensitive genetic male sterility (P-TGMS) by only a significant P × T interaction effect on fertility. Among the japonica EGMS lines studied, PGMS, TGMS and P-TGMS accounted for 32·3, 9·7 and 51·6%, respectively. However, among the indica EGMS lines, no PGMS lines were detected and most of them were TGMS or P-TGMS (61·4 and 35·7%, respectively). The results indicate that the selection of indica PGMS lines of rice might be very difficult. The availability of different types of EGMS rice in two-line system hybrid rice is evaluated and the selection of an ideal model of response to photoperiod and temperature for indica EGMS is discussed.
Postpartum Depression in an Online Community of Lesbian Mothers: Implications for Clinical Practice

A growing number of lesbians are choosing to conceive and raise children. Online communities for lesbian mothers are increasingly popular and discussion forums specific to postpartum depression (PPD) are emerging. Online ethnography (netnography) and content analysis were employed to assess the role of an online forum in PPD and to investigate how the shared experiences of lesbian birth mothers with PPD might inform clinical practice. Disclosure, coping, treatment-seeking, medications, perseverance, and comorbid conditions emerged as themes that characterize online messages and participant experiences. Findings have implications for assessing risks of PPD and for increasing help-seeking behavior among lesbian mothers.
A minimax policy for optimal portfolio choice

The optimal decision problem in portfolio theory considers a decision-maker (DM) who has to optimally invest a proportion of his wealth,x i, in a risky asseti, wherex i ⩾ 0 fori = 1, 2,…,m and ∑ i=1 m x i =l and the return\(\mathop {\tilde r}\nolimits_i \) is random. Any choice of vectorx′ =(x 1,x 2,…,x m ) that is feasible i.e. $$x \geqslant 0,e'x = 1$$ (1) wheree is anm ×l vector with each element unity and prime denotes transpose, is called a portfolio policy with a random return\({\tilde z}\): $$\tilde z = \tilde r'x,\tilde r' = (\mathop {\tilde r}\nolimits_1 ,\mathop {\tilde r}\nolimits_2 ,...\mathop {\tilde r}\nolimits_m$$ (2) With\(E(\tilde r) = \mathop {(\mu }\nolimits_1 ,\mathop \mu \nolimits_2 ,...\mathop \mu \nolimits_m )'\) and\(\operatorname{cov} (\tilde r) = V(\mathop u\nolimits_{ij} ),i,j = 1,2,...,m\)denoting the mean vector and the variance-covariance matrix of\({\tilde r}\) respectively, the mean and variance of return\({\tilde z}\) on a feasible portfolio policy are, respectively given by $$E(\tilde z) = \mu 'x,\operatorname{var} (\tilde z) = x'Vx$$ (3) Denoting the set of parameters byθ = (µ,V), the traditional optimal solution of the portfolio theory solves the following quadratic programming problem (QP): $$\begin{gathered}\min h = x'Vx \hfill \\x \in R \hfill \\\end{gathered}$$ (4) where $$R:\left\{ {x\left| {e'x = 1 \geqslant M,x} \right. \geqslant 0} \right\}$$ (5) M: a fixed positive number By varyingM parametrically, the whole set of optimal or efficient portfolios is determined according to Markowitz’s theory and its various extensions (Szego 1980).
Adapting menu layout to tasks

Abstract Menus are an increasingly popular style of user-system interface. Although many aspects of menu design can affect user performance (e.g. item names and selection methods), the organization of items in menus is a particularly salient aspect of their design. Unfortunately, empirical studies of menu layout have yet to resolve the basic question of how menus should be organized to produce optimal performance. Furthermore, a disturbingly common finding has been that any initial effects of menu layout disappear with practice. Thus it is tempting to conclude that menu organization is not important or that it only affects performance during learning. In this paper we present some reasons to doubt this conclusion. In particular, we have found persistent effects of layout with multiple-item selection tasks, in contrast with studies employing a single-item selection paradigm. The results of a controlled study comparing various menu designs (fast-food keyboards) show that the types of tasks to be performed by users must be considered in organizing items in menus and that there may be sustained effects of menu organization with some tasks. In addition, the results of this study support the use of a formal methodology based on user knowledge for menu design. By comparing the performance of subjects using menus designed using our methodology with the performance of subjects using “personalized” menus, we were able to demonstrate the general superiority of our method for designing menus, and for tailoring menus to meet task requirements as well.
Joint Engagement and the Emergence of Language in Children with Autism and Down Syndrome

Systematic longitudinal observations were made as typically developing toddlers and young children with autism and with Down syndrome interacted with their caregivers in order to document how joint engagement developed over a year-long period and how variations in joint engagement experiences predicted language outcome. Children with autism displayed a persistent deficit in coordinated joint attention; children with Down syndrome were significantly less able to infuse symbols into joint engagement. For all groups, variations in amount of symbol-infused supported joint engagement, a state in which the child attended to a shared object and to language but not actively to the partner, contributed to differences in expressive and receptive language outcome, over and above initial language capacity.
Heparin binding and augmentation of C1 inhibitor activity.

Abstract Heparin and other glycosaminoglycans have profound activity in vitro on the regulation of complement activity. The studies reported here examined the mechanism whereby heparin enhances C1 esterase inhibitor (C1INH) activity on C1 esterase (C1). The interaction of heparin and heparan sulfate with C1INH was first examined using surface plasmon resonance. Heparin was immobilized on a biosensor chip in two orientations, at its reducing end and in midchain, and heparan sulfate was immobilized at its reducing end. Heparin immobilized at its reducing end interacted with C1INH, giving an association constant ( K a ) value of 1.43 × 10 7 M −1 , whereas heparin immobilized in midchain afforded a K a value of 7 × 10 6 M −1 . No interaction between C1INH and heparan sulfate could be observed. Next, the augmentation of C1INH by heparin ( M r (av) 13,000), low-molecular-weight (LMW) heparin ( M r (av) 5000), and heparan sulfate ( M r (av) 11,000) was determined. C1INH alone was at least 10,000 times more active in inhibiting fluid phase C1 compared with erythrocyte-bound C1 (EAC1). When C1 was in the fluid phase, both heparin and LMW heparin were relatively ineffective at augmenting C1INH activity on C1. In contrast, when C1 was present as EAC1, heparin augmented C1INH activity at all C1INH concentrations examined and LMW heparin was up to 1.3 times more effective than heparin. This augmentation only occurred when both C1INH and heparin were present together with the EAC1. Hence, although surface plasmon resonance shows that heparin binds to C1INH, heparin augmentation of C1INH activity appears to require a terniary complex in which cell bound C1 interacts with both heparin and C1INH. This is the first report of LMW heparin augmenting C1INH activity. Heparan sulfate neither interacted with C1INH nor did it augment C1INH activity.
Probabilistic regulation of IL-4 production.

Among a population of uniformly differentiated TH2 cells, only a portion express IL-4 upon stimulation and those that do often express the product of only a single allele. We review the evidence for the basis of IL-4 monoallelism and argue that it depends upon probabilistic expression of the Il4 gene. Further, we argue that probabilistic expression may provide a powerful mechanism through which certain key functions of IL-4, such as immunoglobulin class switching and determination of macrophage phenotype, may be efficiently regulated.
BUOYANT PLUME CALCULATIONS.

Smoke from raging fires produced in the aftermath of a major nuclear exchange has been predicted to cause large decreases in surface temperatures. However, the extent of the decrease and even the sign of the temperature change, depend on how the smoke is distributed with altitude. We present a model capable of evaluating the initial distribution of lofted smoke above a massive fire. Calculations are shown for a two-dimensional slab version of the model and a full three-dimensional version. The model has been evaluated by simulating smoke heights for the Hamburg firestorm of 1943 and a smaller scale oil fire which occurred in Long Beach in 1958. Our plume heights for these fires are compared to those predicted by the classical Morton-Taylor-Turner theory for weakly buoyant plumes. We consider the effect of the added buoyancy caused by condensation of water-laden ground level air being carried to high altitude with the convection column as well as the effects of background wind on the calculated smoke plume heights for several fire intensities. We find that the rise height of the plume depends on the assumed background atmospheric conditions as well as the fire intensity. Little smoke is injected into the stratosphere unlessmore » the fire is unusually intense, or atmospheric conditions are more unstable than we have assumed. For intense fires significant amounts of water vapor are condensed raising the possibility of early scavenging of smoke particles by precipitation. 26 references, 11 figures.« less
Julia Kristeva and the Politics of Life

In her recent writings on the powers and limits of psychoanalysis, Julia Kristeva develops a theory of power and subjectivity that engages implicitly, if not explicitly, with biopolitical themes. Exploring these engagements, this paper draws on Kristeva to discuss the mute symptoms of homo sacer and the regulatory power of the spectacle. Staging an uncommon (and sometimes antagonistic) conversation between Kristeva, Agamben, and Foucault, I construct a field of inquiry that I term the “psychic life of biopolitics.”
Corpuscles of Stannius: lack of direct involvement in regulation of serum sodium, potassium, and chloride in the teleost, Fundulus heteroclitus.

Abstract Removal of the Stannius corpuscles of Fundulus heteroclitus adapted to freshwater, dilute seawater, or seawater, has little effect on serum sodium, potassium, or chloride. Injection of homogenate of Stannius corpuscles into intact or Stanniectomized fish also has no consistent effects on these electrolytes. In light of the marked effects of the operation or injection therapy on serum calcium levels, it is suggested that the physiological role of the corpuscles of Stannius is the maintenance of serum calcium and that observed minor effects on serum monovalent electrolytes are indirect ones.
A Modest Manuscript Within an Impressive Oeuvre: The Hague, Koninklijke Bibliotheek, MS 135 J 9, and the Master of the Guise Hours

MS 135 J 9, a French manuscript in the Koninklijke Bibliotheek [Royal Library] in The Hague, Netherlands, is placed in the framework of the career and oeuvre of the Master of the Guise Hours.
Two's complement extension of a parallel binary division by ten

A division of binary numbers by ten is extended to negative numbers in a two's complement form. The analysis of these negative remainder cases has allowed a more uniform, general approach to the remainder detection problem and should permit an extension to division by other constants.
Parasitoids and ecological risk assessment: Can toxicity data developed for one species be used to protect an entire guild?

Parasitoid wasps are important control agents for a suite of economically important arthropod pests. However, it is well known that hymenoptera in general are highly vulnerable to the effects of chemical pesticides, and so represent an opportunity to better understand the compatibility of biological and chemical control of pests. Closely related species are often used in trials aimed at assessing the effects of different chemical toxicants on hymenoptera. Most of these tests focus on acute toxicity, with few exploring longer-term population outcomes. Here, using a simple mathematical framework, we quantify the relative vulnerability of a suite of parasitoid species to the sublethal effects of a toxicant acting on fecundity. Using an equation that describes a critical extinction threshold, we calculate levels of reduction in fecundity above which parasitoid species important for biological control are driven to local extinction. We apply this framework to four economically important braconid biological control agents (Diachasmimorpha longicaudata, Psyttalia fletcheri, Fopius arisanus, and Diaeretiella rapae), and find that threshold levels vary widely among them. In particular, we find that D. rapae is far more robust to pesticide exposure than the other three species, suggesting that these four species are not interchangeable in terms of risk assessment. Our findings imply that caution should be exercised in assuming species even within the same functional guild may be used as surrogate species for one another.
A dynamic measure of order in structural glasses

Abstract Although some patterns of physical behavior are common in the glass transition and in the properties of supercooled liquids and glasses (characteristic viscoelasticity, temperature dependence of viscosity and relaxation times, property evolution through “physical aging”, difficulties in performing equilibrium measurements or simulations, etc.), it is difficult to arrive at a definition of the glass transition which distinguishes it from other phenomena exhibiting similar features. The present paper addresses this problem by defining a dynamical measure of order involving the average “shape” of particle trajectories in supercooled liquids. This dynamic order parameter should provide a measure of “closeness” to the glass transition and some indirect insights into the physical nature of supercooled liquids and glasses. Arguments are given that the proposed dynamic measure of order [“generalized capacity”, C(T)] is related to the temperature-dependent “effective hydrodynamic radius” RH(T) measured in supercooled liquids and model numerical calculations are given to support this view. Some consequences of the intermittent particle motion at low temperatures for stress relaxation are also discussed.
Evaluation of different methods of inactivation of Newcastle disease virus and avian influenza virus in egg fluids and serum

Viruses conveyed in shipments of eggs, viral diagnostic reagents, or avian serum samples are a potential hazard for susceptible poultry. Different methods of treatment of those materials to eliminate the hazard of virulent and avirulent strains of Newcastle disease virus (NDV) or avian influenza virus (AIV) were evaluated. The NDV strains tested were more thermostable than the AIV strains. The results suggest that standard pasteurization methods would not reliably inactivate the concentrations of NDV used. beta-Propiolactone (BPL) (greater than or equal to 0.025%) inactivated NDV or AIV in allantoic fluid, but higher concentrations were needed to inactivate virus diluted in serum. Hemagglutination (HA) of NDV and AIV and hemolysis (HL) activity of NDV were reduced or eliminated by 0.4% BPL. Formalin (greater than or equal to 0.04%) inactivated either virus but adversely affected HA and HL activity. NDV or AIV was inactivated by binary ethylenimine (BEI) (0.01 M) with no adverse effect on HA or HL. Heat (56 C) or BEI (0.01 M) had no apparent effect on hemagglutination-inhibition (HI) titers of NDV and AIV antisera, the effect of formalin (0.1%) was variable, and BPL (greater than or equal to 0.25%) depressed the HI titers of both antisera. The optimum method should achieve virus inactivation without harming the treated material.
CRT-24 Impact of Insurance Type in Patients with Acute Myocardial Infarction Treated with Percutaneous Coronary Intervention

The goal of this study is to investigate baseline risk factors, angiographic characteristics, interventional procedural information and hospital outcomes in patients with acute myocardial infarction (AMI) treated with percutaneous coronary intervention (PCI) according to insurance status. Recent
Is There a Link Between Fluoridated Water and Osteosarcoma

This study by Dr. Sheila McGuire and others not only refutes a link between fluoride ingestion and osteosarcoma formation, but also suggests that fluoride may protect against this cancer. To test the hypothesis that fluoride is a risk factor for osteosarcoma, a case control study compared the complete residential fluoride histories of osteosarcoma patients with matched hospital-based controls. Fluoridation was not found to be a risk factor for osteosarcoma in the study population. The trend in the data from this small sample study suggests the hypothesis that a protective effect may exist against the formation of osteosarcoma for individuals consuming fluoridated water.
Kinematic mobility analysis of peptide based nano-linkages

Abstract Given that proteins are the nano devices of choice for evolution, it is increasingly believed by scientists that the practical and viable approach to the design and fabrication of artificial nano devices and machines is to use polypeptide chains, protein building blocks found in nature. A peptide chain (building block of proteins) is an open loop serial linkage that in the process of folding is turned into a complex network of closed and open loops by hydrogen and disulphide bonds. Over-constrained closed loops form rigid structural domains in the proteins and therefore reduce the movement flexibility (mobility) of the protein molecules. The objective of this work is to identify the rigid domains and flexible regions in a peptide chain using only one of its native conformations. Protein molecules that exhibit conformation changes upon stimuli consist of rigid domains connected by flexible links. In order be able to design nano devices that will exhibit similar behavior, we need to predict the internal mobility of the molecules. To identify the rigid domains of the peptide chain, we use the Grubler–Kutzbach (GK) criterion to predict the mobility and degrees of freedom of the chain. The majority of the existing methods in the literature for identifying rigid domains involve the comparison of two conformations of a protein in order to identify the rigid domains in the molecule and, therefore, require atom coordinates in these configurations. These methods cannot be effective in the design process where predictive ability based on the structural characteristics of the chain, rather than experimental observations, is the aim. To be able to apply GK criterion, the following procedure is proposed. For any conformation of the peptide chain, hydrogen and disulphide bonds will be established based on the geometric and energy criteria reported in the literature; develop the connectivity matrix for all of the bond and atom connections; based on a search of the connectivity matrix, identify all of the independent loops of the chain; apply GK criterion to independent loops in order to identify the rigid regions as well as to identify the mobility (degrees of freedom) of the flexible regions. This procedure also identifies the flexible domains as well as their degree of flexibility. Identification of rigid domains significantly simplifies the motion modeling procedures that use dihedral angles of the protein chain as variables. The developed methodology is applied to two protein molecules and the results are presented.
Mechanism of corepressor-mediated specific DNA binding by the purine repressor

The modulation of the affinity of DNA-binding proteins by small molecule effectors for cognate DNA sites is common to both prokaryotes and eukaryotes. However, the mechanisms by which effector binding to one domain affects DNA binding by a distal domain are poorly understood structurally. In initial studies to provide insight into the mechanism of effector-modulated DNA binding of the lactose repressor family, we determined the crystal structure of the purine repressor bound to a corepressor and purF operator. To extend our understanding, we have determined the structure of the corepressor-free corepressor-binding domain of the purine repressor at 2.2 A resolution. In the unliganded state, structural changes in the corepressor-binding pocket cause each subunit to rotate open by as much as 23 degrees, the consequences of which are the disengagement of the minor groove-binding hinge helices and repressor-DNA dissociation.
On f-factors of a graph

Abstract This paper probes the relations between f -factors and subgraphs and their degree sequences in a graph when the graph has the odd-cycle property and contains no self-loop. Useful results are derived which greatly simplify tests of the existence of f -factors.
Digital Preservation and Access of Agricultural Materials

Historians and researchers depend on institutions to preserve the records and documents of the past. As the land-grant institution, Colorado State University (CSU) joined in a national, multi-phase National-Endowment-for-the-Humanities-supported grant project to identify and preserve significant materials documenting the history of the agricultural and rural life of the state. This article outlines the history of the grant project, details the challenges and successes of the digitization phase at Colorado State University Libraries, provides usage statistics, and offers a basis for emulation by other institutions by providing an example of a successful preservation and digitization project at a large public university.
Third ventricular glioblastoma multiforme: case report

Intraventricular neoplasms of the third ventricle represent a small minority of intracranial tumors. Furthermore, few cases of solitary, third ventricular glioblastoma multiforme were reported in the literature. The authors report a case of a fifty-nine year old man who presented with progressive gait disturbance, disorientation, diffuse headache, and vomiting. Computed tomography and magnetic resonance imaging (MRI) confirmed a solitary third ventricular ring-enhancing lesion and obstructive hydrocephalus. The final pathology of the lesion upon permanent section was glioblastoma multiforme (GBM). The clinical course, radiologic findings, the possible origin of this lesion, as well as possible treatment regimen are discussed.
Prevalence Estimate of Elevated Pediatric Blood Leads: Two Air Force Bases

After the occurrence of several cases of lead poisoning at Offutt and Randolph Air Force Bases, a cross-sectional study on all children of age 12 or younger was initiated to identify those children with possibly undue lead exposure. A total of 1102 and 784 children at these two bases, respectively, were tested for blood lead values. The aim of this study was to estimate the prevalence of elevated blood lead levels of young children living in on- or off-base housing at the two air force bases. To account for analytical errors and the within-person variability in blood lead measurements, a bivariate lognormal model was employed to estimate the true blood lead values of those children whose initial measurements were 10 micrograms/dL or greater. As a result of accounting for the analytical errors and within-person variance in blood lead measurements, many cases of elevated blood lead levels turned out to be false positives. It was also shown that the relative risk for young children at the two bases having elevated blood leads was the same regardless of where they lived and how old they were. By pooling together the cases, a point estimate for the prevalence of elevated blood leads among young children was 4.2 per 1000 children, with a 95% confidence interval of 1.8 to 8.4 children per 1000 children.
Analysis of Ni/Ti multilayers by X-ray diffraction

Abstract The chemical modulation, structure and strain in Ni/Ti multilayer thin films are analyzed using X-ray diffraction theories. The repeat period of the multilayers used in this study ranges from 1.3 × 10 −9 to 12.8 × 10 −9 m. The composition modulation is obtained by using a kinematical theory of X-ray diffraction. Interplanar spacings and the strain within each atomic layer are found by iteratively fitting the experimental X-ray diffraction curves with the simulated one from a dynamical theory of X-ray diffraction.
Carbonium ion-silane hydride transfer reactions IV. Structure and reactivity at silicon

Abstract Rates of hydride transfer from substituted silanes to the tris(2,6-dimethoxyphenyl)methyl cation were measured spectrophotometrically in acetic acid. For a series of triarylsilanes the value of p was −1.84 and for aryldimethylsilanes p was −1.01. For both series a better correlation was obtained for σ than for σ + . The primary kinetic-isotope effect k H / k D was measured for transfer from triphenylsilane and triphenyldeuteriosilane to the tris(2,6-dimethoxyphenyl)methyl cation, the 9- p -anisylxanthyl cation and the phenyl- p -tolyldeuteriomethyl cation and found to be between 1.51 and 1.89 for the three carbonium ions. The results indicate that the transition state for hydride transfer from silicon involves a four center array (trigonal bipyramid at silicon) in which nucleophilic participation by solvent aids in displacement of hydride from silicon.
A Prospective Study of Childhood and Adolescent Antecedents of Homelessness among a Community Population of African Americans

Much is known about contemporaneous correlates of homelessness from studies of homeless individuals. However, few studies have prospectively examined early antecedents and prevalence of homelessness in community populations. We use data from a 35-year study of a community population of African Americans to examine relationships between homelessness and prior structural, family, school, and behavioral influences. Nearly 22% of males and 16% of females reported homelessness between ages 15 and 42, providing a rare estimate within an African American urban community population. In bivariate analyses, lower school bonds, depressed mood, violent behavior, and running away in adolescence are predictive for both males and females. Teen parenting and angry mood are unique influences for females, while for males, poor first grade classroom conduct and adolescent substance use are unique risks. In multivariate analyses, poor classroom conduct and weaker school bonds predict homelessness among males, while teen parenting does so for females. Running away before age 15 is strongly predictive of later homelessness for both males and females. These results reveal the relative influence of multiple, interrelated early risks on homelessness and confirm our hypothesis that factors linked to other poor outcomes also relate to homelessness, underscoring another benefit to early prevention efforts.
Jamming a Rival′s Learning

Abstract Can a firm (F) cause a rival (R) to learn less about R? Does F care? I explore F′s ability and incentive to affect, or "jam," R′s private learning about R. The model developed does not have unobserved actions or ex ante asymmetric information which previous jamming models require. I find the F wants R not to learn and the more uncertain F believes R is, the more F wants to jam R′s learning. Entry deterrence increases with an entrant′s uncertainty, causing R to want F to believe that R is more certain about R′s beliefs than R really is. Journal of Economic Literature: D82, D83, L13.
Synthesis of optically active verrucarinic acid derivatives

Abstract Two syntheses of verrucarinic acid highlighting an oxidative cleavage of hydroxysulfides and use of mandelate esters for chromatographic resolution are reported.
Psychological Status of Student Drug Users.

The purpose of this study was to determine how a child's self-concept influences their drug attitudes and behaviors. In addition to identifying specific drug practices, students responded to four subscales of the California Test of Personality. “Anti-Social Tendencies” and “Family Relations” correlated significantly and negatively with the use of almost all substances and positively with drug attitude. “Feeling of Belongong” was related negatively to the use of the more dangerous drugs.
Effects of phencyclidine on spontaneous and excitatory amino acid-induced activity of ventral tegmental dopamine neurons: An extracellular in vitro study

Abstract Extracellular single-unit recordings in rat midbrain slices were used to assess the effects of phencyclidine (PCP) on the spontaneous and excitatory amino acid-induced firing of ventral tegmental (VTA) dopamine neurons. Perfusion with PCP concentrations from 10 nM to 100 μM resulted in only minimal decreases in firing rate. Neither excitatory effects nor changes in firing pattern were ever observed upon exposure to PCP. In contrast, PCP selectively antagonized the stimulatory effects of N-methyl-D-aspartate (NMDA), but did not alter α-amino-3-hydroxy-5-methyl-4-isoxazole proprionic acid (AMPA)- or kainate (KA)-induced excitations. These results are discussed in relation to the low-dose stimulatory effects of PCP on ventral tegmental A10 dopamine neurons in the whole animal preparation.
Time varying risk premia for real estate investment trusts: A GARCH-M model

Abstract This study employs the generalized autoregressive conditionally heteroskedastic in the mean (GARCH-M) methodology to investigate the return generating process of real estate investment trusts (REIT). The trade-off between excess returns and the conditional variance was positive for both equity and mortgage REITs but it was significant only for the latter. Changes in interest rates and their conditional variance were found to be inversely related to REIT excess returns. The 1986 tax law had a negative impact on the excess returns to both REIT sectors but the coefficient was significant only for mortgage REITs. The GARCH-M specification was determined to be more appropriate for the mortgage REIT portfolio than for the portfolio of equity REITs.
An origin state method for communication constrained cooperative localization with robustness to packet loss

This paper reports on an exact, real-time solution for server-client cooperative localization over a faulty and extremely bandwidth-limited underwater communication channel. Our algorithm, termed the origin state method, enables a 'server' vehicle to broadcast its navigation information to multiple 'client' vehicles over a bandwidth-limited and faulty communication channel. The server's broadcasted pose-graph can be used in conjunction with an estimator on the client to exactly reproduce the corresponding server-client centralized estimate. We present an evaluation over an extensive real-time field implementation of the proposed algorithm for a multi-agent autonomous underwater vehicle network using underwater acoustic modems to communicate in a synchronous-clock transmission framework.
Assessing the impacts of projected climate change on biodiversity in the protected areas of western North America

Protected areas are a fundamental component of many conservation strategies. They safeguard some of the best examples of unfragmented natural landscapes in many regions, provide important habitat for rare and threatened species, and serve as a refuge from a human-dominated world. As climates continue to change, species distributions, ecological communities, and ecosystems will be altered. An understanding of the trends in these changes can allow protected area managers to develop more effective climate-adaptation strategies. Here, we quantify the relative amount of projected potential climate-driven ecological change across a protected area network by calculating three metrics. We assessed future projected changes in temperature and precipitation, shifts in major vegetation types, and vertebrate species turnover for the protected areas of the Pacific Northwestern region of North America. In general, the degree of projected change in the three metrics followed a longitudinal gradient from the Pacific coast inland toward the continental interior. Protected areas expected to experience the least change are at low elevations near the coast and throughout the Coastal Mountains, whereas areas expected to experience the most change are found at higher elevations in the Rocky Mountains and Great Basin regions. The resulting spatial variation in these impact measures underscores the importance of developing appropriate, location-specific, climate-adaptation strategies in response to disparate trends in future environmental change.
Spindle Pole Organization in Drosophila S2 Cells by Dynein, Abnormal Spindle Protein (Asp), and KLP10A

Dynein is a critical mitotic motor whose inhibition causes defects in spindle pole organization and separation, chromosome congression or segregation, and anaphase spindle elongation, but results differ in different systems. We evaluated the functions of the dynein-dynactin complex by using RNA interference (RNAi)-mediated depletion of distinct subunits in Drosophila S2 cells. We observed a striking detachment of centrosomes from spindles, an increase in spindle length, and a loss of spindle pole focus. RNAi depletion of Ncd, another minus-end motor, produced disorganized spindles consisting of multiple disconnected mini-spindles, a different phenotype consistent with distinct pathways of spindle pole organization. Two candidate dynein-dependent spindle pole organizers also were investigated. RNAi depletion of the abnormal spindle protein, Asp, which localizes to focused poles of control spindles, produced a severe loss of spindle pole focus, whereas depletion of the pole-associated microtubule depolymerase KLP10A increased spindle microtubule density. Depletion of either protein produced long spindles. After RNAi depletion of dynein-dynactin, we observed subtle but significant mislocalization of KLP10A and Asp, suggesting that dynein-dynactin, Asp, and KLP10A have complex interdependent functions in spindle pole focusing and centrosome attachment. These results extend recent findings from Xenopus extracts to Drosophila cultured cells and suggest that common pathways contribute to spindle pole organization and length determination.
Origin and Continuity of Desmosomes

The problems of desmosome formation and maintenance are different from those of the other cell components discussed in this volume. Desmosomes, and other cell attachment devices, are not organelles but rather are modifications of the cell periphery. No specific chemical or ultrastructural components have been identified in desmosomes which are not common to the rest of the peripheral cytoplasm and membrane of the cell. The problem of desmosome origin, therefore, seems to be one of localization and organization of ubiquitous components, a process less well understood than the reproduction of true organelles.
Spanking in the home and children's subsequent aggression toward kindergarten peers

Although spanking of children is almost universal in U.S. society, its effects are not well understood. We examined the longitudinal relation between parental spanking and other physical punishment of preschool children and children's aggressive behavior toward peers later in kindergarten. A total of 273 boys and girls from diverse backgrounds served as subjects. The findings were consistent with a socialization model in which higher levels of severity in parental punishment practices are associated with higher levels of children's subsequent aggression toward peers. Findings indicated that children who had been spanked evidenced levels of aggression that were higher than those who had not been spanked, and children who had been the objects of violent discipline became the most aggressive of all groups. Patterns were qualified by the sexes of the parent and child and subtypes of child aggression (reactive, bullying, and instrumental). The findings suggest that in spite of parents' goals, spanking fails to promote prosocial development and, instead, is associated with higher rates of aggression toward peers.
Divine providence, simple foreknowledge, and the ‘Metaphysical Principle’

In this essay, I challenge David P. Hunt's defence of the utility of simple foreknowledge for divine providence against the 'Metaphysical Principle'. This principle asserts that circular causal loops are impossible. Hunt agrees with this principle but maintains that so long as the deity does not use simple foreknowledge in such a way that causal loops unfold, the Metaphysical Principle in not violated. I argue that Hunt's position still allows for the possibility of such causal loops and this itself is a breach of the Metaphysical Principle.
Detection of breast malignancy: diagnostic MR protocol for improved specificity.

PURPOSE: To prospectively determine if a combined magnetic resonance (MR) protocol that includes T1-weighted dynamic contrast agent–enhanced (DCE) MR imaging, hydrogen 1 (1H) MR spectroscopy, and T2*-weighted perfusion MR imaging improves specificity in the diagnosis of breast cancer. MATERIALS AND METHODS: The combined MR imaging–MR spectroscopy protocol was performed in 50 patients after positive findings at mammography but prior to biopsy. Single-voxel proton MR spectroscopy and perfusion MR imaging were conducted only if DCE MR images showed rapid contrast enhancement in the lesion. Biopsy results were used as the reference for comparison with MR results and for calculation of sensitivity and specificity in the detection of breast malignancy. RESULTS: DCE MR imaging alone showed 100% sensitivity and 62.5% specificity. The specificity improved to 87.5% with the addition of 1H MR spectroscopy and to 100% with the further addition of perfusion MR imaging. Twenty-eight patients underwent both MR spectrosc...
Estimating the relative reinforcing strength of (+/-)-3,4-methylenedioxymethamphetamine (MDMA) and its isomers in rhesus monkeys: comparison to (+)-methamphetamine.

(±)3,4-Methylenedioxymethamphetamine (MDMA) is an analog of methamphetamine (MA) and a drug of abuse. MA, MDMA, and its isomers release monoamine neurotransmitters with varying selectivities and would, therefore, be predicted to vary in their relative strength as reinforcers. This study compared self-administration of MA, MDMA, and its isomers using a progressive-ratio schedule in rhesus monkeys. Rhesus monkeys [n = 6, MA and MDMA; n = 5, (+)-MDMA and (−)-MDMA] were prepared with chronic i.v. catheters and allowed to self-administer cocaine or saline in daily baseline sessions. When responding was stable, MA (0.006–0.1 mg/kg per injection), MDMA (0.025–0.8 mg/kg injection), (+)-MDMA (0.025–0.8 mg/kg per injection), or (−)-MDMA (0.05–0.8 mg/kg per injection) was made available in test sessions. MA, MDMA, and (+)-MDMA functioned as positive reinforcers in all monkeys with a potency relationship of MA > (+)-MDMA > (±)-MDMA. Two of five monkeys took (−)-MDMA above saline levels. Dose–response relationships were biphasic for MA and (±)-MDMA, and asymptotic for (+)-MDMA. In terms of maximum number of injection per session, a measure of relative reinforcing strength, the order was MA > (+)-MDMA = (±)-MDMA > (−)-MDMA. MDMA and (+)-MDMA were consistent positive reinforcers, but weaker than MA, whereas (−)-MDMA was, at best, a weak reinforcer in some monkeys. The reinforcing strength of MDMA appears to derive primarily from (+)-MDMA. Because MDMA and its isomers have been shown to have relatively higher serotonin to dopamine releasing potency, these data support the hypothesis that increasing 5-HT releasing potency relative to DA is associated with weaker reinforcing effects.