cssi/SciSciGPT-SciSciNet huggingface dataset:
Atomistic Simulation of Dislocation-Defect Interactions in Cu

The mechanisms of dislocation-defect interactions are of practical importance for developing quantitative structure-property relationships, mechanistic understanding of plastic flow localization and predictive models of mechanical behavior in metals under irradiation. In copper and other face centered cubic metals, high-energy particle irradiation produces hardening and shear localization. Post-irradiation microstructural examination in Cu reveals that irradiation has produced a high number density of nanometer sized stacking fault tetrahedra. Thus, the resultant irradiation hardening and shear localization is commonly attributed to the interaction between stacking fault tetrahedra and mobile dislocations, although the mechanism of this interaction is unknown. In this work, we present a comprehensive molecular dynamics simulation study that characterizes the interaction and fate of moving dislocations with stacking fault tetrahedra in Cu using an EAM interatomic potential. This work is intended to produce atomistic input into dislocation dynamics simulations of plastic flow localization in irradiated materials.
Responses of the iguanid lizard Anolis carolinensis to four organophosphorus pesticides

Abstract Dose related mortality and cholinesterase effects of parathion, methyl parathion, azinphos-methyl and malathion on Anolis carolinensis were investigated. The comparative effects of the four compounds on fish, birds and mammals are well known, but the effects of organophosphates on reptiles have not been studied critically. Sensitivity and patterns of mortality from exposure to the pesticides resemble those of birds and mammals rather than those of other poikilothermic vertebrates. Possible symptoms of epinephrine accumulation were observed in exposed animals; this side effect is consistent with the known mechanisms of the pesticides. Our findings indicate that brain cholinesterase activity is related to dose, that 50% inhibition of cholinesterase is associated with death and that 40% inhibition indicates sublethal exposure. Anolis lizards are frequently exposed to pesticides in the field and they may be useful in monitoring the hazards posed to a variety of wildlife species.
Phenotypic divergence among the members of the African malaria mosquitoes and strategies of persistence throughout the dry season

Genetic heterogeneity in the African malaria mosquito, Anopheles gambiae, led to the recognition of chromosomal forms over 30 years ago by Prof Coluzzi and colleagues, who proposed that divergence between these populations was extensive and related to adaptation to mesic vs arid habitats as well as to particular types of larval habitats. Re-defined as “molecular forms,” genetic divergence among these populations has been elaborated by cutting-edge molecular studies, providing support for their status as distinct evolutionary units as well as against it, and fueling a lively debate that recently culminated in the elevation of the M and S forms to species, as A. coluzzii and A. gambiae, respectively. However, beyond geographical and seasonal observations, phenotypic differences between the forms have received far less attention. Surprisingly, minimal differences were found in adult body size, reproductive output, wet-season longevity, susceptibility to Plasmodium, desiccation resistance, and high-temperature tolerance; together, these results appear to undercut the implications of genetic divergence. Yet, evidence for differential predator-mediated developmental success of larvae supported adaptive divergence to distinct larval habitats, while additional studies showed that reproductive isolation across most of their ranges is maintained primarily by swarm segregation and possibly by within-swarm recognition based on flight pattern, sound, or chemical cues. More recently, studies have revealed striking divergence in dry-season persistence strategies between Sahelian populations of these species. Accordingly, A. coluzzii persists through the dry season in situ, by a form of dormancy (aestivation), whereas A. gambiae recolonizes the area by wind-assisted long-distance migration. These results reveal profound ecological (behavioral and physiological) divergence between these populations, lending substantial support for their status as distinct species. Additionally, they affirm Prof Coluzzi’s insights about the evolutionary forces that have led to their speciation. Although these findings provide strong clues as to the process of speciation in this complex, important gaps in this understanding remain, and hold promise for fresh scientific insights and for malaria control.
Effectiveness of the Dairy Cattle Feed Formulation System in Developing Lactating Rations

Abstract Thirty Virginia dairy herds were solicited as cooperator herds. The objective was to test in the field the Dairy Cattle Feed Formulation System, a computerized feeding management system. During 12 mo, 13 herds used recommendations of the system regularly, 5 herds were occasional users or made modifications to the recommendations, 11 herds followed other feeding recommendations, and one herd was dropped from the study. Increase in milk production during 12 mo averaged 354, 220, and −39 kg per cow for regular, occasional, and no formulation users. Milk fat test, body weight, and body condition were not affected by frequency of using the formulation system. Days open were reduced in herds which were regular users (−13.5, 6.8, and 2.1). The coefficient of variability for milk production within herds was 28%. When herds were divided into two groups of lactating cows or when herds used automatic (magnetic) feeders, daily milk yield averaged 28.1, 17.4, and 33.3 kg, for high and low groups or cows with access to automatic feeders. Coefficients of variability were 13, 22, and 10%.
Multiple flooding events in Martian outflow channels

[1] The large outflow channels of Chryse Planitia, Mars, are thought to have been carved by floodwaters discharged from an aquifer beneath a confining cryosphere. However, conventional models of groundwater flow require optimistically high permeabilities to produce, in a single flooding event, the discharge rates and volumes inferred from channel morphology. Additionally, discharge likely ceased upon refreezing of chaotic terrain fractures carrying it to the surface, further limiting the volume of water produced in a single flood. It is thus probable that multiple surface discharge events were required, and we quantify this hypothesis with regional groundwater simulations. Each discharge event is triggered by cryosphere disruption due to superlithostatic hydraulic head at the channel source region and is terminated by cryosphere fracture refreezing. Before the next event, head is allowed to recover with the aid of distal aquifer recharge constrained by previous global groundwater models. Our baseline model, which emulates the source region of Kasei Valles, yields a minimum of 2900 flooding events even for high depth-averaged aquifer permeabilities corresponding to near-surface values of 10−9 m2. Although fewer events are required for other circum-Chryse channels, formation by a single flood remains improbable. We suggest that unrealistically high numbers of floods may be circumvented by an alternative model involving the local ponding of surface discharge to form standing bodies of water. Episodic failure of these bodies produces flood outbursts which erode the channels.
Longitudinal evaluation of GCF IFN-gamma levels and periodontal status in HIV+ patients.

La perte du support parodontal et la perte des dents en relation sont des decouvertes regulieres parmi les patients HIV + . L'etiologie de cette destruction peut etre une augmentation des niveaux des cytokines pro-inflammatoires et une augmentation subsequente de l'activite de la maladie parodontale. Le but de cette etude a ete d'etudier les associations entre l'IFN-γ du fluide creviculaire gingival (GCF) et les mesures cliniques de la maladie parodontale chez les individus HIV + . Le IFN-γ du GCF et l'etat parodontal ont ete suivis de sites selectionnes chez 33 patients HIV + durant une periode de six mois. Les mesures cliniques incluaient l'indice gingival (GI), l'indice de plaque (PlI), le saignement au sondage (BOP), la profondeur de poche (PD), la perte d'attache (AL) et des echantillons de GCF ont ete preleves de quatre incisives inferieures et du sextant posterieur superieur droit chez chaque patient lors de l'examen initial et six mois apres au moyen de strips en papier sterile. Les teneurs en IFN-y du GCF ont ete determinees par ELISA en sandwich. Un site progressif etait defini comme un site qui avait 2 mm ou plus de perte d'attache durant le suivi des six mois. Vingt-cinq des 264 sites examines ont montre 2 mm ou plus de perte d'attache durant cette periode. Des teneurs superieures en IFN-y dans le GCF ont ete trouvees dans les sites progressifs que dans les sites ne progressant pas (p <0.001). Les teneurs en IFN-y du GCF etaient en forte correlation avec les mesures cliniques prises au moment de l'examen de depart et six mois apres (0.001<p<0.01). Ces donnees indiquent que les sites avec de hautes teneurs en IFN-y dans le GCF presentent un risque significativement plus important pour la progression de la parodontite chez les patients HIV + .
Photopigment and spectral sensitivity in the bioluminescent fish Porichthys notatus

Digitonin extracts from retinas of the marine fish Porichthys notatus, from California and Puget Sound (USA), contain a single photopigment with maximum absorbance at 498 nm. In the presence of hydroxylamine the final product of bleaching absorbs maximally at 367 nm, indicating that the photopigment is based on retinal. Spectral sensitivity measurements performed on intact eyes and eye-cup preparations in darkadapted and selectively light-adapted states yield curves which suggest that the retina of P. notatus contains at least 3 different types of receptors. In the darkadapted state, the spectral sensitivity curve has a broad peak, with a maximum between 480 and 500 nm. In the blue and red light-adapted states, in addition to depressing the sensitivity, the shape of the sensitivity curve also changes. Under these conditions new peaks appear which suggest the presence of at least two different types of cones, with sensitivity maxima in the blue and the green regions of the spectrum, respectively. Comparison of the spectral sensitivity curves with the in vivo bioluminescence emission spectrum of the fish gives an especially good correspondence and suggests that the fish is able to perceive the bioluminescence of its own species.
Random band models with lines of pure Doppler shape.

The behavior of random band models composed of lines of pure Doppler shape for several irradiance distribution functions is investigated. The particular irradiance distribution functions chosen are: (1) constant irradiance, (2) exponential distribution, (3) truncated S−1 distribution, and (4) the exponential-tailed S−1 distribution. The curves of growth for the first two models are found to have the asymptotic (log)12 behavior characteristic of an isolated Doppler line while the latter two models show a (log)32 dependence.
Sample sealing approaches for Mars Sample Return caching

Sealing methods for encapsulating samples in 1 cm diameter thin-walled sample tubes applicable to future proposed Mars Sample Return missions were investigated based on power requirements, operation in the Martian environment, dust tolerance, shock and vibration, maintenance of sample integrity, hermeticity, packaging requirements, mission risk, and ability for autonomy. Techniques implemented include a spring energized Teflon sleeve plug, a crimped tube seal, a heat-activated shape memory alloy plug, a shape memory alloy activated cap, a solder-based plug, and a solder-based cap. Testing will be performed on the prototypes to determine their sensitivity to particle contamination along the sealing surface, Helium leak rate, and survivability over a range of temperatures to help recommend sealing techniques for the proposed Mars Sample Return campaign.
Modeling and mitigating the effects of supply chain disruption in a defender–attacker game

The outcomes of a defender–attacker game depend on the defender’s resources delivered through military supply chains. These are subject to disruptions from various sources, such as natural disasters, social disasters, and terrorism. The attacker and defender are at war; the defender needs resources to defeat the attacker, but those resources may not be available due to a supply chain disruption that occurs exogenously to the game. In this paper, we integrate a defender–attacker game with supply chain risk management, and study the defender’s optimal preparation strategy. We provide analytical solutions, conduct numerical analysis, and compare the combined strategy with other protection strategies. Our results indicate that: (a) the defender benefits in a defender–attacker game by utilizing supply chain risk management tools; and (b) the attacker’s best response resource allocation would not be deterred by capacity backup protection and/or inventory protection. The feature of this paper is that the defender, being the downstream user of the supply chain, is involved in a strategic contest against the attacker. This model is different than game theory applied to private-sector supply chains because most game theoretic models of private sector supply chains usually explore relationships between suppliers and firms in the same supply chain or between multiple firms competing in the marketplace for customers. Therefore, supply chain risk management for such a military application imposes effects that have not been studied before.
Solid phase synthesis of peptidotriazoles with multiple cycles of triazole formation

Peptidotriazoles, unnatural oligomers with alternating amide and triazole linkages, are synthesized efficiently on solid support. The key transformations involve multiple cycles of 1,2,3-triazole formation, using soluble Cu(I) catalyst and conditions that do not generate precipitate on solid support nor require exclusion of oxygen. Our synthetic protocol will enable the preparation of other unnatural oligomers with multiple triazoles using solid phase methodologies.
Irradiated tumor cells adenovirally engineered to secrete granulocyte/macrophage-colony-stimulating factor establish antitumor immunity and eliminate pre-existing tumors in syngeneic mice

The specific aim of this study was to examine the prophylactic as well as the therapeutic efficacies of irradiated mouse CT26 colon cancer cells, infected with recombinant adenoviruses harboring cDNAs specific for granulocyte macrophage-colony-stimulating factor (GM-CSF), interferon (IFN-gamma) and monocyte chemotactic protein1 (MCP-1). Results showed that tumor cells secrete the respective cytokines for several days after infection and subsequent irradiation. Vaccination with irradiated GM-CSF-secreting CT26 cells protected 90% of syngeneic mice challenged with live parental cells. On the other hand, vaccination with irradiated IFNgamma or MCP-1-secreting CT26 cells totally failed to protect mice from tumor development after challenge with parental cells. None of the tumor-free mice initially vaccinated with irradiated GM-CSF-producing CT26 cells developed tumor upon repeated challenge with parental cells during the entire observation period. The establishment of specific and long-lasting antitumor immunity following vaccination with GM-CSF-producing tumor cells requires the simultaneous presence of GM-CSF and tumor antigen at the vaccine site. Depletion of CD8+ cells, but not CD4+ cells, blocked the vaccine efficacy of GM-CSF-producing tumor cells. Subcutaneous injection of irradiated GM-CSF-producing CT26 cells also effectively prevented the growth of a small load of parental tumor that was implanted 3 days earlier or the development of metastatic foci in the lung from intravenously injected parental cells either 7 days before or 3 days after vaccination. Our data thus show that, in these experimental tumor models, subcutaneous injection of irradiated tumor cells adenovirally, transduced with the GM-CSF gene leads not only to prevention of growth of subsequently implanted tumor but also to elimination of pre-existing and metastatic tumors.
Elevated Fos-like immunoreactivity in the brains of postpartum female prairie voles, Microtus ochrogaster.

This study investigated the expression of the protein product of the immediate early gene c-fos in the brains of female prairie voles (Microtus ochrogaster) in association with pregnancy and postparturient activities including maternal behavior, lactation and postpartum estrus. Fos expression was assessed in female voles that were late in pregnancy, nonpregnant or at one of three different times postpartum (0–8, 12–24, and 24–48 h, respectively). A significant increase in the number of cells displaying Fos immunoreactivity (Fos-ir) was observed during the 0–8 h and 12–24 h postpartum time periods in the accessory olfactory bulbs, medial preoptic area, hypothalamus (specifically, the supraoptic nucleus, ventromedial hypothalamus, and paraventricular nucleus), lateral septum, bed nucleus of the stria terminalis, and primary somatosensory area of the brain. The number of Fos-ir cells decreased after 24 h postpartum. There were no significant changes in Fos-ir cell numbers in the primary olfactory bulbs, hippocampus, or caudate putamen. The neural activation of the medial preoptic area, accessory olfactory bulbs, hypothalamus, and bed nucleus is consistent with reports in rats of Fos induction associated with the onset of maternal behavior. In voles postpartum estrous behavior begins and ends 0–12 h after parturition. Maternal behavior, including lactation, is initiated at the same time but persists for several weeks. The highest Fos-ir cell numbers reported here coincide with the timing of postpartum estrous behavior in this species.
320 EFFECT OF IN-UTERO INTRAVENOUS ADMINISTRATION OF THYROXINE AND OTHER HORMONES ON LUNG FLUID LECITHIN SPHINGOMYELIN (L/S) RATIO OF THE FETAL LAMB

Glucocorticoid hormones influence lung maturation, but their effect on the L/S ratio has not been clearly demonstrated. Prior to lung maturity 9 fetal lambs (mean 118 days) were chronically catheterized in-utero. Fetal lung fluid was diverted into an external drainage bag by a Foley catheter through a tracheotomy. A single dose of Cortisol 2.5-5.0 mg., Dexamethasone 200/ng, T4 500/ng, or T3 1-150/ng was administered via the jugular catheter for 3 days during the first treatment period beginning 3-12 days after surgery. An identical course of treatment was repeated 10 days later. Fetal blood pH and plasma level of the administered hormone were monitored daily. The L/S profile for each fetal lamb was compared to a mean curve derived from 7 control fetal lambs receiving saline solution at comparable periods. No change in the lung fluid L/S pattern was found after repeated administration of Cortisol or Dexamethasone in 3 fetal lambs. A sharp increase in the ratio was seen after 2 courses of T4 treatment in 2 fetal lambs while T4 treatment during the second period alone failed to produce this effect. Administration of 1-10/ng of T3 during the second period alone produced no change in the L/S ratio in the 3 remaining lambs. These preliminary data suggest that pharmacological doses of T4 can alter the lung fluid L/S ratio in fetuses previously primed with that hormone.
Unobtrusive Control in a Leadership Organization: Integrating Control and Resistance

This study examined decision making by members of a volunteer organization as a duality of unobtrusive control and resistance. A central premise of the organization—the need for aggressive economic development—was isolated from field observations of the organization's meetings. Grounded theory analysis of interviews with organizational alumni revealed that both the control and resistance features of the identification construct help to describe how they enacted or resisted the organization's premise in their political orientation. Findings revealed that the gap that occurs between individuals' understanding of the organization's premise and individuals' decisions based upon that premise is an opening in which other identifications may influence them. These influences result in decisions that may or may not be in the best interest of the organization.
The Politics of Casino Gambling Detroit Style

To recover from the effects of disinvestment in the auto industry, Detroit is being promoted as a tourist/convention center. Casinos have been suggested as revenue enhancers and as tourist magnets. Despite the poor reviews Atlantic City received from introducing casinos, three casino referenda have been attempted in Detroit. The 1988 anticasino campaign is reviewed in this article. The voters again rejected casinos in that campaign, but the important differences in the nature and character of the appeal reveal that status politics does matter when mobilizing the working class. The rejection of casinos is viewed as a setback with long-term implications.
Chronic caloric restriction preserves mitochondrial function in senescence without increasing mitochondrial biogenesis.

Caloric restriction (CR) mitigates many detrimental effects of aging and prolongs life span. CR has been suggested to increase mitochondrial biogenesis, thereby attenuating age-related declines in mitochondrial function, a concept that is challenged by recent studies. Here we show that lifelong CR in mice prevents age-related loss of mitochondrial oxidative capacity and efficiency, measured in isolated mitochondria and permeabilized muscle fibers. We find that these beneficial effects of CR occur without increasing mitochondrial abundance. Whole-genome expression profiling and large-scale proteomic surveys revealed expression patterns inconsistent with increased mitochondrial biogenesis, which is further supported by lower mitochondrial protein synthesis with CR. We find that CR decreases oxidant emission, increases antioxidant scavenging, and minimizes oxidative damage to DNA and protein. These results demonstrate that CR preserves mitochondrial function by protecting the integrity and function of existing cellular components rather than by increasing mitochondrial biogenesis.
Differential effects of μ and κ opioid analgesics on cerebral glucose utilization in the rat

Abstract The autoradiographic 2-deoxy- d -[1-14C]glucose ([14C]2-DG) method was used to map the effects of subcutaneous (s.c.) morphine (8.0 mg/kg), oxymorphone (0.4 mg/kg) and nalbuphine (16.0 mg/kg) on local cerebral glucose utilization (LCGU), and index of local brain function. At the dosages administered, effects of the opioid agonists on LCGU were very restricted. The μ agonists, injected 15 min before [14C]2-DG, decreased LCGU in thalamic nuclei, including some of those which have been implicated in somatosensory processing, and in the dorsal tegmental nucleus. Nalbuphine did not produce these effects, but stimulated LCGU in nuclei of the spinal tract of the trigeminal nerve and in the globus pallidus. All of the effects on LCGU were blocked by prior administration of naloxone (1.0 or 10.0 mg/kg, s.c., 5 min before morphine or nalbuphine, respectively). Our findings suggest that different supraspinal mechanisms are involved in the actions of μ vs κ opioids, and indicate that the [14C]2-DG procedure might be helpful in elucidating the anatomical areas involved.
Specificity of aminoglycoside antibiotics for the A-site of the decoding region of ribosomal RNA

Abstract Background: Aminoglycoside antibiotics bind to the A-site of the decoding region of 16S RNA in the bacterial ribosome, an interaction that is probably responsible for their activity. A detailed study of the specificity of aminoglycoside binding to A-site RNA would improve our understanding of their mechanism of antibiotic activity. Results: We have studied the binding specificity of several aminoglycosides with model RNA sequences derived from the 16S ribosomal A-site using surface plasmon resonance. The 4,5-linked (neomycin) class of aminoglycosides showed specificity for wild-type A-site sequences, but the 4,6-linked class (kanamycins and gentamicins), generally showed poor specificity for the same sequences. Methylation of a cytidine in the target RNA, as found in the Escherichia coli ribosome, had negligible effects on aminoglycoside binding. Conclusions: Although both 4,5- and 4,6-linked aminoglycosides target the same ribosomal site, they appear to bind and effect antibiotic activity in different manners. The aminoglycosides might recognize different RNA conformations or the interaction might involve different RNA tertiary structures that are not equally sampled in our ribosome-free model. These results imply that models of ribosomal RNA must be carefully designed if the data are expected to accurately reflect biological activity.
Optimal control of a boiling water reactor in load-following via multilevel methods

A multilevel method is applied to the load-following control of a boiling water reactor using a nodal reactor model with practical operational constraints and thermal limits. Due to the very large size of the problem, a decomposition is made using hierarchical control techniques. The optimization of the resulting subproblems is performed using the feasible direction method. An objective functional, of quadratic form, is defined to reflect the control objective, namely to achieve the desired thermal power (tracking) with minimum effort, returning to the initial xenon and iodine concentration as closely as possible. Nodal source equation and discretized Xe-I dynamic equations are formulated as equality constraints, while the linear heat generation rate and the rate of power increase are formulated as inequality constraints. Core flow and control rod position are the control variables. A simplified model of the core is used, with 4 x 4 fuel assemblies that have one control rod at the center.
Photovoltaics: More solar cells for less

A solar-cell design based on silicon microwires achieves efficient absorption of sunlight while using only 1% of the active material used in conventional designs.
Effects of GBR 12909 and cocaine on cocaine-maintained behavior in rhesus monkeys

The reinforcing effect of the high affinity dopamine reuptake inhibitor GBR 12909 (I-[Z-[bis(4-fluorophenyl)methoxy]ethyl)4(3_phenylpropyl)piperazine) was compared with that of cocaine, and the effects of both GBR 12909 and cocaine pretreatments were evaluated on behaviour maintained by cocaine in rhesus monkeys. Increasing dose per injection of intravenously-delivered GBR 12909 or cocaine led to increased rates of lever-press responding. Maximum cocaine-maintained rates were higher and occurred at a smaller dose than maximum rates of GBR 12909-maintained responding. Presession intravenous administration of either GBR 12909 or cocaine (0.32, 1.0 or 3.2 mg/kg) resulted in dose-dependent decreases in rates of cocaine-maintained responding when high doses of cocaine, which engendered high response rates, were available early in the session. Under these conditions, the decrease in response rates was associated primarily with decreases in running rate rather than with a lengthen ing in post-reinforcement pause times. The decreases in running rate produced by both cocaine and GBR 12909 probably reflect an unconditioned rate-disruptive effect of these drugs on cocaine-reinforced responding rather than a reduction in the reinforcing efficacy of cocaine.
Glycome analysis by oligosaccharide profiling using liquid chromatography/mass spectrometry

Liquid chromatography/mass spectrometry equipped with a graphitized carbon column is useful for the simultaneous analysis of oligosaccharides. By using capillary column and nanoelectrospray ion source, the method can be used for the oligosaccharide profiling of sub microgram quantities of glycoproteins. This oligosaccharide profiling is expected to be a powerful tool for the glycome analysis. We demonstrate a potential application of oligosaccharide profiling in glycomics with two examples, the structural analysis of N-linked oligosaccharides from a gel-separated glycoprotein, and the differential analysis of N-linked oligosaccharides in cells.
A satellite investigation of energy flux and inferred potential drop in auroral electron energy spectra

The relationship between auroral electron energy flux and the inferred accelerating potential drop for accelerated Maxwellian distributions is investigated on the basis of Atmospheric Explorer D spectral measurements. An analytical approximation for the total downward energy flux carried by an isotropic Maxwellian electron population accelerated by a field-aligned electrostatic potential drop is derived which is valid for values of the electron energy/characteristic accelerated Maxwellian distribution energy which are less than the difference between the ratio of the magnetic field strengths at the altitude of observation and the altitude of potential drop, and unity. Data from the Low Energy Electron Experiment on board AE D obtained on both the dayside and the nightside during periods of significant inverted-V type electron precipitation shows that the 455 energy spectra considered, 160 of them, obtained between 60 and 85 deg invariant latitude, could be fit to accelerated Maxwellian distributions. The 160 Maxwellian spectra are then shown to be in agreement with the predictions of the accelerated Maxwellian model. Finally, analysis of individual spectra suggests that the altitude of the inferred potential drop is at a maximum near the center of the inverted-V structures.
Milk protein expression and ductal morphogenesis in the mammary gland in vitro: hormone-dependent and -independent phases of adipocyte-mammary epithelial cell interaction.

Abstract Epithelial cell differentiation frequently occurs in situ in conjunction with supporting mesenchyme or connective tissue. In embryonic development the importance of the supporting mesenchyme for cytodifferentiation and morphogenesis has been demonstrated in several epithelial tissues, but the importance of epithelial-connective tissue interactions is less well studied in adult epithelial organs. We have investigated the interaction of adult mammary epithelial cells with adipocytes, which compose the normal supporting connective tissue in the mammary gland. Mammary epithelial cells from mice in various physiological states were cultured on cellular substrates of adipocytes formed from cells of the 3T3-L1 preadipocyte cell line. We found that there were two distinct phases to the interaction of epithelial cells with adipocytes. Cytodifferentiation of the epithelial cells and milk protein production were dependent on lactogenic hormones (insulin, hydrocortisone, and prolactin), whereas ductal morphogenesis was lactogenic hormone independent. When cultured on preadipocytes or adipocytes, mammary epithelial cells from never pregnant, pregnant, lactating, and involuting mice responded to lactogenic hormones rapidly by producing and secreting large amounts of α-, β-, and γ-casein and α-lactalbumin. This response was seen in individual as well as in clusters of epithelial cells, but was not seen if the same cells were cultured on tissue culture dishes without adipocytes, on fibroblasts (human newborn foreskin fibroblasts) or in the presence of adipocytes but in the absence of lactogenic hormones. Continued incubation of mammary epithelial cells on adipocytes in the presence or absence of lactogenic hormones resulted in the formation of a branching ductal system. Mammary epithelial cells in ducts that formed in the absence of lactogenic hormones produced no casein, but rapidly synthesized casein when subsequently exposed to these hormones. Ultrastructural studies revealed that the formation of a basement membrane occurs only in co-cultures of mammary epithelium with adipocytes or preadipocytes. Ultrastructural changes associated with secretion occurred only in the presence of lactogenic hormones. We propose that growth and formation of a ductal system in vitro can occur in the absence of lactogenic hormones, but that certain environment-associated events must occur if the epithelium is to become responsive to lactogenic hormones and undergo the cytodifferentiation associated with lactation.
Kinematics of Protostellar Objects in the ρ Ophiuchus A Region

We present the detection of infall, rotation and outflow kine matic signatures towards both a protostellar source, VLA 1623 and what was initially thought to be a pre-protostellar core, SM1N, in theOphiuchus A region. The kinematic signatures of early star formation were detected in the dense molecular gas surrounding the embedded sources using high signal-to-noise millimeter and submillimeter data. Centroid velocity maps made with HCO + J=4!3 and J=1!0 line emission exhibit the blue bulge signature of infall, w hich is predicted to be seen when infall motion dominates over rotational motion. Further evidence for infalling gas is found in the HCO + blue asymmetric line profiles and red asymmetric opacity pro files. We also performed CO J=3!2 and J=1!0 observations to determine the direction, orientation, an d extent of molecular outflows, and report the discovery of a new bipolar outflow possibly driven by SM1N. Subject headings:stars: circumstellar matter-ISM: clouds-stars: formatio n
Measurement of benzoylecgonine and cocaine in urine, separation of various cocaine metabolites using reversed-phase high-performance liquid chromatography

The application of reversed-phase high-performance liquid chromatography to the measurement of benzoylecgonine and cocaine in urine is described. Following a simple extraction and clean-up procedure, chromatography is performed using a column containing an octadecylsilica coated packing, elution with 17% acetonitrile in pH 2.7 phosphate buffer and ultraviolet detection at 200 or 235 nm. The detection limit is ca.0.1 microgram of drug per ml urine, and using the ethyl ester of benzoylecgonine as an internal standard, benzoylecgonine and cocaine are quantified with coefficients of variation of 7.0 and 2.8%, respectively. The procedure has been applied to urines from subjects receiving intranasal cocaine, and compared to the enzyme multiplied immunoassay technique. The chromatography procedure also permits the separation of norcocaine and benzoylnorecgonine.
The Gene for Nucleoside Diphosphate Kinase Functions as a Mutator Gene inEscherichia coli

Abstract Nucleoside diphosphate (NDP) kinase is a key enzyme in the control of cellular concentrations of nucleoside triphosphates, and has been shown to play important roles in various cellular activities such as developmental control, signal transduction and metastasis in eukaryotic systems. In this study, the gene for NDP kinase of Escherichia coli (ndk) was disrupted and surprisingly found to be dispensable without any discernible effects on cell growth or morphology. However, a mutator phenotype was found in ndk -disruption strains; frequencies of spontaneous mutations to rifampicin resistance and nalidixic acid resistant significantly increased. A higher frequency in reversion mutations was observed with use of an amber mutation in the kanamycin-resistance gene in an ndk -disruption strain. Imbalance in dNTP pools, in particular a significant increase of the dCTP content was observed, which is likely to result in the higher spontaneous mutation rates. These results suggest that NDP kinase, although not essential, plays an important role in the appropriate balance of intracellular dNTP pools to maintain a high DNA replication fidelity. Strains with ndk − pyk A − pyk F − as well as ndk − scs − were constructed without any discernible effect on cell growth, indicating that there is yet another enzyme(s) catalyzing nucleoside triphosphate synthesis, in addition to NDP kinase, pyruvate kinases and succinyl CoA synthetase.
Alignment of P Waves for Signal Averaging

Signal averaged atrial activity recorded from the body surface is finding increased use in assessing atrial arrhythmias. The process of signal averaging is critically dependent upon precise alignment of the waveform of interest. The alignment accuracy of wide (0.01-300 Hz) and narrow (10-300 Hz) bandpass filtered P waves recorded from the body surface were compared to atrial electrograms recorded from temporary pacing wires. The locations of the filtered P waves relative to the atrial electrogram were calculated beat-by-beat for 100 beats in 15 patients aged 1 month to 71 years. The standard deviation of the alignment error for the wide filtered surface P wave averaged 1.7 +/- 0.8 msec and for the narrow filtered P waves was 0.8 +/- 0.4 ms. These results demonstrate that high pass filtering will improve alignment accuracy, and therefore, improve frequency resolution for the analysis of signal averaged P waves.
ON THE CONVERGENCE AND BEHAVIOR OF THREE DIMENSIONAL NORMAL FORMS

Abstract Low codimensional bifurcations of control systems have been classified using the theory of normal forms. However, the normal form theory was developed as local results. To understand the behavior of control systems outside a local area of a bifurcation point, it is necessary to study the convergence of the normal forms if the vector fields are analytic. The convergence is a long time open problem. In this paper, we address the convergence problem of normal forms for three dimensional control systems. Bounded attractors are found for a family of such normal forms, which include the controlled Lorenz system as a special case.
Culture, instruction, and assessment

Instruction and assessment need to be understood and thought about within the cultural context in which they occur. Educators and educational researchers may make assumptions that apply in their home culture but not elsewhere. And even different subcultures within an overall mainstream culture may have different views on instruction and assessment, and what constitutes intelligent performance in each. In this article, I consider the relevance of culture to instruction and assessment. I describe studies that show the importance of understanding instruction and assessment in their cultural contexts, and conclude that education and its goals must be understood in such contexts.
Spherical caps in low Reynolds-number tube flow

Abstract The stability, velocity and additional pressure drop (in excess of the Poiseuille drop) associated with the motion of large, rigid, neutrally buoyant spherical caps (including hemispheres) in low Reynolds-number tube flow was studied. It was found that spherical caps were stable in an orientation in which they were centered in the tube with their spherical face forward and with their base plane perpendicular to the direction of flow. For spherical caps in this stable orientation, measurements of the velocity and the additional pressure drop revealed that both were relatively independent of cap thickness and cap spacing, but depended strongly on cap diameter. The experimental pressure-drop data for hemispheres when multiplied by two showed close agreement with theoretical results derived for spheres.
Cyclic temperature effects on growing-finishing swine

Abstract 1. 1.|Growing swine (average 15.8 kg) had increased rate of feed intake and feed required per unit of gain and rate of gain decreased at 5 compared to 20°C, while feed intake and feed conversion were not affected by cycling temperatures. 2. 2.|Rate of gain and feed conversion of finishing swine (65–100 kg) were negatively affected both by 5°C and by cycles of ± 12°C during the initial 4-wk period but not during the final 3 wk. 3. 3.|Evaluations of immune function through total leukocyte count, cell differentiation, skinfold response to mitogen injection and antibody formation to a foreign protein in the finishing swine displaced mixed response to temperature and cyclicity.
A helix-destabilizing protein substrate devoid of heterocyclic bases.

Summary A polynucleotide analog devoid of heterocyclic bases, poly(ribosylurea phosphate), was prepared by KMnO4 oxidation of poly(C). This analog binds effectively to seveal nucleic acid helix-destabilizing proteins, including gene 32 protein from T4 bacteriophage, UP1 from calf thymus, a protein from rat liver, and RNase A, which is a DNA helix-destabilizing protein. Binding was demonstrated by the ability of poly(ribosylurea phosphate) to inhibit protein-induced depression of polyd(A-T) Tm, as well as, in the case of the T4 and rat liver proteins, the quenching of intrinsic protein tryptophan fluorescence upon interaction with this polynucleotide analog. This substrate may prove useful in assessing the role that protein-ribose phosphate backbone interactions play in the binding specificity of helix-destabilizing proteins.
How do tissues respond to damage at the cellular level? The role of cytokines in irradiated tissues

The capacity of ionizing radiation to affect tissue function, control tumor growth and elicit pathological sequelae has been attributed in great part to its effects on cellular DNA, which, as the transmitter of genetic information, can both register damage and perpetuate it. Nonetheless, multicellular organisms function as the result of the cooperation of many cell types. What then occurs when individual cells are damaged by ionizing radiation? Is tissue response a sum of cellular effects such as cell death and DNA damage? Or does the tissue respond as a coherent unit to the damage of its parts? In this paper, data in support of the latter model that indicate a role for cytokines, in particular transforming growth factor beta1, as critical components of extracellular signaling pathways that mediate tissue response to radiation will be reviewed. The key to manipulating the consequences of radiation exposure lies in understanding the complex interplay of events initiated at the cellular level, but acting on the tissue.
City Museums and Urban Learning

(2013). City Museums and Urban Learning. Journal of Museum Education: Vol. 38, No. 1, pp. 3-8.
Electrical spin-injection into silicon from a ferromagnetic metal/tunnel barrier contact

The electron’s spin angular momentum is one of several alternative state variables under consideration on the International Technology Roadmap for Semiconductors (ITRS) for processing information in the fundamentally new ways that will be required beyond the ultimate scaling limits of silicon-based complementary metal–oxide–semiconductor technology1. Electrical injection/transport of spin-polarized carriers is prerequisite for developing such an approach2,3. Although significant progress has been realized in GaAs (ref. 4), little progress has been made in Si, despite its overwhelming dominance of the semiconductor industry. Here, we report successful injection of spin-polarized electrons from an iron film through an Al2O3 tunnel barrier into Si(001). The circular polarization of the electroluminescence resulting from radiative recombination in Si and in GaAs (in Si/AlGaAs/GaAs structures) tracks the Fe magnetization, confirming that these spin-polarized electrons originate from the Fe contact. The polarization reflects Fe majority spin. We determine a lower bound for the Si electron spin polarization of 10%, and obtain an estimate of ∼30% at 5 K, with significant polarization extending to at least 125 K. We further demonstrate spin transport across the Si/AlGaAs interface.
Exposure of Immunocompetent Adult Mice to Pneumocystis carinii f. sp. muris by Cohousing: Growth of P. carinii f. sp. muris and Host Immune Response

There has been emerging evidence that immunocompetent hosts can harbor Pneumocystis in their lungs. The purpose of this study was to determine the kinetics of Pneumocystis carinii f. sp. muris infection in adult immunocompetent mice and the host immune response to the organisms. To accomplish this, we exposed adult immunocompetent mice to SCID mice infected with P. carinii f. sp. muris by cohousing. We found that P. carinii f. sp. muris was detectable in the lungs of cohoused immunocompetent mice by PCR by 3 weeks after the beginning of cohousing. At about 4 weeks of cohousing, P. carinii f. sp. muris was readily detectable in the lungs of mice by microscopic techniques. Also at this time, P. carinii f. sp. muris-specific immunoglobulin G was found in the sera of the mice, and CD62low CD4- and CD8-positve T cells accumulated in the lungs. Shortly after this immune response, the P. carinii f. sp. muris organisms were cleared from the lungs. Adult mice cohoused for only 1 week also contained P. carinii f. sp. muris cysts detectable by silver staining at 5 and 6 weeks after the beginning of cohousing. We also found that the P. carinii f. sp. muris organisms grew to greater numbers in the lungs of BALB/c mice than in those of C57BL6 mice. This indicates that immunocompetent hosts develop a mild infection with P. carinii f. sp. muris which resolves in 5 to 6 weeks when there is a detectable immune response to the organism. Once an acquired immune response was initiated, the P. carinii f. sp. muris organisms were quickly eliminated without clinical signs of disease.
Indiscriminate friendliness and terror of strangers in infancy: Contributions from the study of infants in foster care

Une attitude excessivement et aveuglement amicale envers les etrangers et une anxiete severe envers les etrangers ont ete decrites dans le travail diagnostique sur les troubles de l'attachement (voir l'Association Americaine de Psychiatrie, 1994; Lieberman & Pawl, 1988; Zeanah, 1996; Zeanah, Mamman, & Lieberman, 1993). De maniere assez surprenante, peu de recherches se sont portees sur ces patterns de comportement anormaux. Dans cet article, nous presentons des etudes de cas de nourrissons places dans des familles adoptives d'accueil et qui ont fait preuve d'une attitude excessivement et aveuglement amicale, ainsi que d'une terreur des etrangers. Les enfants places en familles adoptives d'accueil ont endure des traumas lies a l'attachement allant bien au dela de l'experience de la plupart des bebes, y compris des modes de soin emotionnellement absents, des maltraitances physiques et sexuelles de la part des modes de soin, et l'interruption inevitable du mode de soin inherente au placement en familles d'accueil. Nous affirmons que dans certains cas de telles circonstances extremes forcent les enfants places en familles d'accueil a developper des mecanisms d'adaptation, particulierement dans des situations qui menacent le systeme d'attachement, comme par exemple l'approche d'un etranger. Cette population d'enfants permet donc malheureusement d'examiner des questions sur la maniere dont les troubles de l'attachement se developpent. Nous suggerons des explications possibles pour les phenomenes lies a une attitude excessivement et aveuglement amicale et a la terreur des etrangers.
A prospective study of dietary fiber types and symptomatic diverticular disease in men.

To examine prospectively dietary fiber calculated from food composition values based on analytic techniques and specific dietary fiber types in relation to risk of diverticular disease, we analyzed data from a prospective cohort of 43,881 U.S. male health professionals 40-75 y of age at base line; subjects were free of diagnosed diverticular disease, colon or rectal polyps, ulcerative colitis and cancer. The insoluble component of fiber was inversely associated with risk of diverticular disease relative risk (RR) = 0. 63, 95% confidence interval (CI), 0.44-0.91, P for trend = 0.02, and this association was particularly strong for cellulose (RR = 0.52, 95% CI, 0.36-0.75, P for trend = 0.002). The association between diverticular disease and total dietary fiber intake calculated from the AOACstandards method was not appreciably different from results using the Southgate or Englyst method [for AOAC method, RR = 0.60, 95% CI, 0.41-0.87; for Southgate method, RR = 0.61, 95% CI, 0.42-0. 88; for Englyst method, RR = 0.60, 95% CI, 0.42-0.87, for the highest quintiles]. Our findings provide evidence for the hypothesis that a diet high in dietary fiber decreases the risk of diverticular disease, and this result was not sensitive to the use of different analytic techniques to define dietary fiber. Our findings suggest that the insoluble component of fiber was significantly associated with a decreased risk of diverticular disease, and this inverse association was particularly strong for cellulose.