cssi/SciSciGPT-SciSciNet huggingface dataset:
Survival and Homeostatic Proliferation of Naive Peripheral CD4+ T Cells in the Absence of Self Peptide:MHC Complexes

TCR-self peptide:MHC interactions play a critical role in thymic positive selection, yet relatively little is known of their function in the periphery. It has been suggested that continued contact with selecting MHC molecules is necessary for long-term peripheral maintenance of naive T cells. More recent studies have also demonstrated a role for specific self peptide:MHC complexes in the homeostatic expansion of naive T cells in lymphopenic mice. Our examination of these processes revealed that, whereas self class II MHC molecules do have a modest effect on long-term survival of individual CD4+ T cells, interactions with specific TCR ligands are not required for peripheral naive CD4+ T cell maintenance. In contrast, selective engagement of TCRs by self-peptide:MHC complexes does promote proliferation of CD4+ T cells under severe lymphopenic conditions, and this division is associated with an activation marker phenotype that is different from that induced by antigenic stimulation. Importantly, however, the ability of naive T cells to divide in response to homeostatic stimuli does not appear to be stringently dependent on TCR-self peptide:MHC interactions. Therefore, these results show that the factors regulating survival and homeostatic expansion of naive T cells in the periphery are not identical. In addition, we provide evidence for a novel form of T cell proliferation that can occur independently of TCR signaling and suggest that this reflects another mechanism regulating homeostatic T cell expansion.
Titan's Organic Factory

Researchers have identified molecules in the atmosphere of one of Saturn's moons that are responsible for its smog-like haze.
Formation of functional tissue from transplanted adrenocortical cells expressing telomerase reverse transcriptase

We report the first use of human telomerase reverse transcriptase (hTERT) expression in experimental xenotransplantation. Previously, we showed that bovine adrenocortical cells can be transplanted into severe combined immunodeficient (SCID) mice, and that these cells form functional tissue that replaces the animals' own adrenal glands. We cotransfected primary bovine adrenocortical cells with plasmids encoding hTERT, SV40 T antigen, neo, and green fluorescent protein. These clones do not undergo loss of telomeric DNA and appear to be immortalized. Two clones were transplanted beneath the kidney capsule of SCID mice. Animals that received cell transplants survived indefinitely despite adrenalectomy. The mouse glucocorticoid, corticosterone, was replaced by the bovine glucocorticoid, cortisol, in the plasma of these animals. The tissue formed from the transplanted cells resembled that formed by transplantation of cells that were not genetically modified and was similar to normal bovine adrenal cortex. The proliferation rate in tissues formed from these clones was low and there were no indications of malignant transformation.
Multicultural Teacher Education: Developing a Hermeneutic Disposition

A colleague referred to multicultural teacher education as a set of those classes that preservice teachers take that help them to better hide their bigotry. The comment, though cynical, echoed a fairly pervasive sentiment that educators feel toward multicultural education and its function in teacher education. Preservice teachers, no matter the field, are required to complete multicultural teacher education (MTE) courses in preparation for teaching students from diverse backgrounds. However, a focus on skills-based training for cultural competency in handling diverse classrooms (for example, skills and competency building or field experiences) is inadequate, since it is not enough to learn to simply shield one’s bigotry by acquiring a skill set that helps one “deal” with people from other racial, ethnic, cultural, religious, and otherwise different groups.
Stabilizing health monitoring for wireless sensor networks

Wireless sensor networks (WSNs) comprised of low-cost devices tend to be unreliable, with failures a common phenomenon. Being able to accurately observe the network health status -- of nodes of each type and links of each type -- is essential to properly configure applications on WSN fabrics and to interpret the information collected from them. In this paper we study accurate network health monitoring in WSNs. Specifically, we reconsider the well-known problem of message-passing rooted spanning tree construction and its use in PIF (propagation of information with feedback) for the case of a WSN. We present a stabilizing protocol, Chowkidar, that is initiated upon demand; that is, it does not involve ongoing maintenance, and it terminates with accurate results, including detection of failure and restart during the monitoring process. Our protocol is distinguished from others in two important ways. Given the resource constraints of WSNs, it is message-efficient in that it uses only a few messages per node. And it tolerates ongoing node and link failure and node restart, in contrast to requiring that faults stop during convergence. We have implemented the protocol as part of enabling a network health status service that is tightly integrated with a remotely accessible wireless sensor network testbed, Kansei, at The Ohio State University. We report on experimental results.
Supreme Court Power Play: Assessing the Appropriate Role of the Senate in the Confirmation Process

The Bush Administration will likely have the opportunity to make a number of appointments to the Supreme Court, however such nominations may experience contentious confirmation hearings in the Senate. When such an appointment opportunity does present itself questions are bound to arise concerning the appropriate role of the United States Senate in the confirmation of Supreme Court nominees under the advice and consent provisions of article II of the United States Constitution. Disputes over the Senate's proper role and scope of inquiry have seemed to emerge whenever a nominee has faced the confirmation process, and have been a timeworn subject of legal debate. In this article we assess the proposition that the Senate should have an active role in the confirmation process which includes investigation into a nominee's ideological beliefs and constitutional philosophy. We begin by examining the background of the Constitution's advice and consent phraseology and consider early applications of the confirmation process by senators during the eighteenth and nineteenth centuries. We then discuss the struggle for judicial selection power between the Senate and the President and conclude by suggesting the need for an active Senate response to executive nominations.
The Utopian Function of the Enemy in the Thought of the Frankfurt School

The concept of the enemy, as Carl Schmitt tirelessly emphasized, is an essential political concept. For Schmitt, it even defines the essence of the political. Just as there can be no friends without the possibility of enemies, so too is there no politics without the possibility of hostility and antagonism. A world at peace, tolerant and free from conflict, may be a desideratum, but it can never be secured.Perhaps the most interesting response to Schmitt's politics of enmity is found in the work of the Frankfurt School, who always maintained an ambivalent relation to Schmitt's work. In Adorno and Horkheimer's great book, The Dialectic of Enlightenment, the concept of the enemy is subjected to a dialectic critique intent on disclosing the concept's ambiguous potential. They show, through an interpretation of German anti-Semitism, that under certain conditions the enemy is not only the enemy but is also, against all expectations, the friend. Under such conditions, the one who is feared - the Jew - is not only feared, but also desired. And this desire, Adorno and Horkheimer insist, is Utopian through and through.My paper "The Utopian Function of the Enemy in the Thought of the Frankfurt School" investigates the Utopian dimension of the enemy in the work of the critical theorists. Implicit in Adorno and Horkheimer's work on anti-Semitism is the claim not only that the enemy is often enough the desired friend, but that once this logic of reversal is uncovered, the enemy could emerge anew as the disavowed friend. Uncovering the Utopian current in the concept of the enemy is an important feature of the Utopian politics of the Frankfurt School, and it is their contribution to the politics of peace and reconciliation [also friendship, love, harmony] that Carl Schmitt never envisioned.
d_{x^2-y^2} Pair Domain Walls

Author(s): White, Steven R; Scalapino, DJ | Abstract: Using the density matrix renormalization group, we study domain wall structures in the t-J model at a hole doping of x=1/8. We find that the domain walls are composed of d_{x^2-y^2} pairs and that the regions between the domain walls have antiferromagnetic correlations that are pi phase shifted across a domain wall. At x=1/8, the hole filling corresponds to one hole per two domain wall unit cells. When the pairs in a domain wall are pinned by an external field, the d_{x^2-y^2} pairing response is suppressed, but when the pinning is weakened, d_{x^2-y^2} pair-field correlations can develop.
Positive control of sporulation-specific genes by the IME1 and IME2 products in Saccharomyces cerevisiae.

Abstract In the yeast Saccharomyces cerevisiae, meiosis and spore formation require the induction of sporulation-specific genes. Two genes are thought to activate the sporulation program: IME1 and IME2 (inducer of meiosis). Both genes are induced upon entry into meiosis, and IME1 is required for IME2 expression. We report here that IME1 is essential for expression of four sporulation-specific genes. In contrast, IME2 is not absolutely essential for expression of the sporulation-specific genes, but contributes to their rapid induction. Expression of IME2 from a heterologous promoter permits the expression of these sporulation-specific genes, meiotic recombination, and spore formation in the absence of IME1. We propose that the IME1 and IME2 products can each activate sporulation-specific genes independently. In addition, the IME1 product stimulates sporulation-specific gene expression indirectly through activation of IME2 expression.
Optimal risk transfer for agents with germs

Abstract We introduce a new class of risk measures called generalized entropic risk measures (GERMS) that allow economic agents to have different attitudes towards different sources of risk. We formulate the problem of optimal risk transfer in terms of these risk measures and characterize the optimal transfer contract. The optimal contract involves what we call intertemporal source-dependent quotient sharing , where agents linearly share changes in the aggregate risk reserve that occur in response to shocks to the system over time, with scaling coefficients that depend on the attitudes of each agent towards the source of risk causing the shock. Generalized entropic risk measures are not dilations of a common base risk measure, so our results extend the class of risk measures for which explicit characterizations of the optimal transfer contract can be found.
Peroxisome Proliferator-activated Receptor α Interacts with High Affinity and Is Conformationally Responsive to Endogenous Ligands

Abstract Although the peroxisome proliferator-activated receptor (PPARα) binds and is activated by a variety of synthetic xenobiotics, the identity of the high affinity endogenous ligand(s) is incompletely resolved. Likewise, it is not known how putative endogenous ligands alter PPARα conformation in order to affect transcriptional regulation. Direct fluorescence binding and fluorescence displacement assays showed for the first time that PPARα exhibits high affinity (1–14 nm Kd values) for unsaturated long chain fatty acyl-CoAs as well as unsaturated long chain fatty acids commonly found in mammalian cells. Fluorescence resonance energy transfer between PPARα aromatic amino acids and bound corresponding naturally occurring fluorescent ligands (i.e. cis-parinaroyl-CoA, trans-parinaric acid) yielded intermolecular distances of 25–29 A, confirming close molecular interaction. Interestingly, although PPARα also exhibited high affinity for saturated long chain fatty acyl-CoAs, regardless of chain length (1–13 nm Kd values), saturated long chain fatty acids were not significantly bound. In contrast to the similar affinities of PPARα for fatty acyl-CoAs and unsaturated fatty acids, CoA thioesters of peroxisome proliferator drugs were bound with 5–6-fold higher affinities than their free acid forms. Circular dichroism demonstrated that high affinity ligands (long chain fatty acyl-CoAs, unsaturated fatty acids), but not weak affinity ligands (saturated fatty acids), elicited conformational changes in PPARα structure, a hallmark of ligand-activated nuclear receptors. Finally, these ligand specificities and induced conformational changes correlated functionally with co-activator binding. In summary, since nuclear concentrations of these ligands are in the nanomolar range, long chain fatty acyl-CoAs and unsaturated fatty acids may both represent endogenous PPARα ligands. Furthermore, the finding that saturated fatty acyl-CoAs, rather than saturated fatty acids, are high affinity PPARα ligands provides a mechanism accounting for saturated fatty acid transactivation in cell-based assays.
Effects of System Dynamics and Applied Force on Adhesion Measurement in Colloidal Probe Technique

Abstract Dynamic pull-in/pull-off forces were quantitatively measured using an AFM colloidal probe technique. Two spherical colloids made of silicon dioxide (SiO 2 ) and gold (Au) that were attached to an AFM cantilever were approached to and retracted from a silicon wafer specimen, where the speed of tip approaching/retracting (i.e., vertical dynamics) and specimen sliding (i.e., horizontal dynamics) was controlled. First, when the vertical dynamics of colloidal tip was applied on the stationary silicon wafer specimen, it was observed that the slower tip approaching showed higher pull-in force, while the pull-off force was dependent on both the applied force and the retracting speed. For the two colloidal tips, it was found that the higher applied force and the faster tip retraction led to the higher pull-off force. Next, under the constant speed of tip approach and retraction, horizontal dynamics was applied to the silicon wafer specimen. It was observed that the horizontal motion of the specimen made the pull-off force lower, which could be attributed to the breakage of adhesive asperity junctions at the interface. The pull-off force was further decreased at faster horizontal motion of the specimen due to the longer sliding distance. Therefore, from the systematic experiments of dynamic adhesion measurement, it could be known that if a micro/nano-system is under dynamic surface interaction, its adhesive force cannot be fully described by a conventional quasi-static adhesion model but it should include the effects of applied system dynamics in both normal and tangential directions.
The Effects of Poverty on Children's Socioemotional Development: An Ecological Systems Analysis

Bronfenbrenner's process-person-context-time model is used to examine theories that explain the adverse effects of economic deprivation on children's socioemotional development. In his model, each of five structures of the ecological environment-microsystems, mesosystems, exosystems, macrosystems, and chronosystems-is subsumed within the next higher level. Theories of the effects of poverty on proximal processes in the microsystem of the family have the most research support, but processes in other microsystems such as the peer group and school and in other levels of the ecological environment may also explain the relation between economic deprivation and children's socioemotional functioning. Social work practice and policy implications are drawn from the analysis.
Peripheral Vein Infusion of Dextrose/Amino Acid Solutions ± 20% Fat Emulsion

The purpose of this study was to evaluate the incidence of phlebitis occurring during peripheral infusion of nutrient solutions with and without 20% fat emulsions. Eighty patients were randomly assigned to one of four groups: (1) dextrose/amino acids-630 mOsmol/liter; (2) dextrose/amino acids/fat emulsion-706 mOsmol/liter; (3) dextrose/amino acids-882 mOsmol/liter and; (4) dextrose/amino acids/fat emulsion-983 mOsmol/liter. The peripheral infusion site was examined daily and the number of changes in infusion sites were recorded and the degree of phlebitis encountered was graded. The four groups were similar in the mean number of iv site changes per patient and per day. The average grade of phlebitis was similar (0.23-0.27 events/day) among the four groups. Infiltration occurred more frequently with butterfly needle while phlebitis occurred more frequently with plastic angiocatheters. Patients appeared to tolerate peripheral infusion with high osmolar solutions just as well as lower osmolar solutions. Concurrent infusion with a 20% fat emulsion did not alter the number of iv site changes or the incidence or degree of phlebitis reported and thus, did not appear to have a protective effect on the vein when infused with dextrose/amino acid solutions.
Anterior segment optical coherence tomography (AS-OCT): a novel diagnostic instrument for conjunctivochalasis

Purpose To evaluate cross-sectional conjunctivochalasis area (CChA) and tear meniscus area (TMA) using Fourier-Domain-RTVue-100 optical coherence tomography (OCT) before and after conjunctival cauterization and to evaluate inter- and intraobserver reliability. Methods A total of twelve eyes of 7 patients with conjunctivochalasis aged 56 to 87 were evaluated. After topical anesthesia, conjunctival cauterization was performed on the inferior bulbar conjunctiva. All patients underwent anterior segment OCT (AS-OCT) imaging prior to and 4 weeks after the procedure. Cross-sectional TMA and CChA at 3 locations (nasal, center and temporal areas) were measured in all patients. Results Non-significant increases (p= 0.177) in TMA as a whole (3 locations combined) were observed at following cauterization. CChA measurements significantly decreased in all 3 locations after cauterization (p< 0.001). Mean CChA decreased from 0.247 ± 0.24 mm2 to 0.054 ± 0.79 mm2. For two measurements of TMA by examiner 1, intraclass correlation coefficients (ICC) ranged from 0.998 to 0.999. Among two examiners, Cronbach’s alpha reliability coefficients were as high as 0.993 and 0.997 before and after conjunctival cauterization. Regarding the CChA measurements, ICC values were similar to those of TMA, but Cronbach’s alpha reliability coefficients were slightly less. Conclusion This study indicates the AS-OCT is a useful and reproducible instrument to measure cross-sectional area of conjunctiva prolapsing into the tear meniscus of patients with conjunctivochalasis. The method can monitor effectiveness of thermo reduction of conjunctivochalasis.
Alcohol-induced modulation of the insulin-like growth factor system in early chick embryo cranial tissue

Background: Fetal alcohol exposure has been shown to reduce fetal/embryonic growth. The insulin-like growth factor (IGF) system plays a major role in normal growth and development of the embryo. The purpose of this study was to gain a better understanding of the effects of alcohol (ethanol, EtOH) exposure on the insulin-like growth factors, their binding proteins, and receptors during embryonic development. Methods: After the administration of either alcohol or chick Ringer's solution to individual eggs at the start of incubation, type-1 IGF receptors, IGF-binding proteins (IGFBPs) as well as IGF-1 and IGF-2 levels were measured in chick embryo craniums on days 5, 6, 7, and 8 of incubation. Results: Levels of the IGF-1 receptor protein were not significantly different between treatment groups on any day studied. In EtOH-treated embryos, the 30 kDa IGFBP levels were significantly higher than vehicle levels on days 5 and 6. On day 6, IGF-1 levels were significantly lower in the alcohol-treated embryos compared with levels in vehicle-treated embryos of the same age. By day 8 of incubation, IGF-1 levels were significantly higher and the 30 kDa IGFBP levels were significantly lower in the alcohol-treated group compared with vehicles. These results indicate an initial EtOH-associated reduction in the amount of IGF-1 available to bind to its receptor (bioavailability), followed by increased IGF-1 bioavailability by day 8. Conclusions: The elevated IGFBP levels and reduced IGF-1 levels on days 5 and 6 of incubation are congruent with an overall reduction in the bioavailability of IGF-1 during this period and correlate with the decreased embryo weight observed in the alcohol-treated embryos. An increased bioavailability of IGF-1 observed by day 8 may represent a rebound effect and is associated with increases in ornithine decarboxylase activity, a marker of increased growth.
On strong anticipation

We examine Dubois's [Dubois, D., 2003. Mathematical foundations of discrete and functional systems with strong and weak anticipations. Lecture Notes in Computer Science 2684, 110-132.] distinction between weak anticipation and strong anticipation. Anticipation is weak if it arises from a model of the system via internal simulations. Anticipation is strong if it arises from the system itself via lawful regularities embedded in the system's ordinary mode of functioning. The assumption of weak anticipation dominates cognitive science and neuroscience and in particular the study of perception and action. The assumption of strong anticipation, however, seems to be required by anticipation's ubiquity. It is, for example, characteristic of homeostatic processes at the level of the organism, organs, and cells. We develop the formal distinction between strong and weak anticipation by elaboration of anticipating synchronization, a phenomenon arising from time delays in appropriately coupled dynamical systems. The elaboration is conducted in respect to (a) strictly physical systems, (b) the defining features of circadian rhythms, often viewed as paradigmatic of biological behavior based in internal models, (c) Pavlovian learning, and (d) forward models in motor control. We identify the common thread of strongly anticipatory systems and argue for its significance in furthering understanding of notions such as ''internal'', ''model'' and ''prediction''.
Syntheses and X-Ray Crystal Structures of Cassiferaldehyde and Analogs

Abstract Cassiferaldehyde, a recently discovered naturally occurring tyrosinase inhibitor, and six of its analogs, in which the aldehyde group has been replaced by various other functionalities, have been synthesized by a short and simple sequence starting from 2,3-dihydroxybenzaldehyde. Single-crystal x-ray structures of cassiferaldehyde as well as its methyl ketone, nitrile, and carboxylic acid analogs are reported.
Nuclear magnetic resonance studies of 5-aminolevulinate demonstrate multiple forms in aqueous solution☆

Abstract 5-Aminolevulinic acid (ALA), the common precursor of heme and chlorophyll, can exist in a variety of forms at neutral pH. 13 C NMR studies of [3- 13 C]ALA, [4- 13 C]ALA, and [5- 13 C]ALA have been used to demonstrate that the predominant species in solution under physiologic conditions is the ketone. The mole fraction of the hydrate is about 0.6%. To further substantiate the existence of the hydrate, 13 C NMR was used to monitor 18 O exchange at C 4 of [4- 13 C]ALA with H 2 , 18 O. Confirmation of the existence of the hydrate was achieved through direct observation by 1 H NMR. The mole fractions of the enol forms of ALA are each below 0.3%. Although direct observation of the enol forms of ALA has not been achieved, enol formation has been indirectly demonstrated by monitoring hydrogen exchange at the C 3 and C 5 methylene groups by 1 H NMR in D 2 O. In neutral phosphate buffer, hydrogen exchange occurs readily at both C 3 and C 5 at a ratio of rates of 1:4. In N -tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid-KOH buffer the hydrogen exchange rates are more than an order of magnitude slower than in phosphate buffer, but the ratio of the exchange rates remains unchanged. The results suggest that phosphate catalyzes enolization at both C 3 and C 5 . To evaluate the role of the C 5 substituent in the proton exchange reactions, levulinate and 5-chlorolevulinate (5-CLA) were also monitored for proton exchange at C 3 and C 5 . For levulinate, the hydrogen exchange rates in phosphate buffer are two to three orders of magnitude slower than for ALA, and the rate of hydrogen exchange at C 5 is three times slower than hydrogen exchange at C 3 . The enolization rate at C 5 of 5-CLA is identical to ALA while enolization at C 3 is about threefold slower for 5-CLA than ALA. These NMR and kinetic studies suggest that under physiologic conditions, ALA rapidly equilibrates between the ketone, the hydrate at C 4 , and two or more different enols (C 3 C 4 and C 4 C 5 ). The alternative forms of ALA may be biologically significant as active site structures for ALA synthase, glutamate semialdehyde transaminase, or porphobilinogen synthase. These NMR studies have also elucidated the structures of condensation products of ALA which can be formed under physiologic conditions. The alternative forms of ALA, as well as the autocondensation products, may serve as the active toxin in porphyrias characterized by elevated ALA levels (e.g., lead poisoning).
Thirty-five-day Periodicity in Her X-1

THE binary neutron star X-ray source Her X-l displays a variety of complex phenomena as well as the well understood 1.24-s neutron star rotational period and the 1.7-d orbital period1. Notable and striking among these phenomena is a series of extended low periods during which the source is not seen. These lows last about 24 d and repeat with a period of 35 d. Here I propose an explanation of this behaviour in terms of eclipses produced by a precessing ring at the rim of an accretion disk surrounding the neutron star.
Cardiac Target Organ Damage in Hypertension: Insights from Epidemiology

Hypertension is an important risk factor implicated in the development of multiple common cardiac conditions, including coronary atherosclerosis, heart failure, and atrial fibrillation. Epidemiologic studies have provided insights into the shared pathogenesis of hypertension and subclinical as well as clinically evident cardiac diseases. The mechanistic common ground between chronic blood pressure elevation and cardiac disease likely begins early in life. Understanding these connections will aid ongoing efforts to identify individuals at risk, develop targeted therapeutics, and improve overall outcomes for individuals with elevated blood pressure in the population at large.
Unsaturated flow in anisotropic heterogeneous media: a centrifuge study

Anisotropic and heterogeneous flow in unsaturated porous media is dependent on saturation conditions, and currently there exist limited options that adequately model this phenomenon. Herein, a modified unsaturated flow apparatus (UFA) and scaled centrifuge tests are used to investigate variations in unsaturated hydraulic conductivity. The method is used to find the unsaturated hydraulic conductivities for a layered system comprised of porous media with different hydraulic conductivities, which is tested under elevated levels of gravitational acceleration. The procedure is useful in reducing model size and test time, resulting in a feasible setup for laboratory scale experiments. Steady state volumetric water content is achieved under each pair of applied inflow rate and centrifuge speeds, allowing the determination of a corresponding unsaturated hydraulic conductivity. The setup also allows for rotation of the layered system for measurement of both vertical and horizontal hydraulic conductivities. The obtained values of hydraulic conductivity show a good fit to theoretical models and the degrees of anisotropy obtained are consistent with the literature. Overall, the results obtained using the modified unsaturated flow apparatus (UFA) indicate a great potential for further studying unsaturated hydraulic conductivity in anisotropic heterogeneous media, especially those with very low hydraulic conductivities.
Variable Perfusion of the Lung in Bronchogenic Carcinoma as Measured by 133 Xenon

A case of bronchogenic carcinoma is reported in which the left lung was essentially nonperfused at resting levels of lung volume and became relatively well perfused at maximum inspiration. Air-containing alveoli in the involved lung were not in communication with major airways based on distribution of inhaled 133 xenon and clearance of perfused 133 xenon.
Effect of vinpocetine on age‐related differences in brain function of aged fischer rats

Vinpocetine, an eburnamenine derivative, is under clinical investigation as a cerebral activator for use in Alzheimer's and other diseases characterized by symptomatic cognitive and attentional deficits. In this study, vinpocetine was evaluated by examining its effect on the electrocorticogram (ECoG) of aged (26-month-old) Fischer-344 rats. Significant age-related differences were apparent for all ECoG parameters examined, suggesting a cerebral deficit in aged rats. Vinpocetine, administered orally (p.o.) over the dose range of 0.3 to 30 mg/kg/day p.o. for 5 days, diminished the age-related differences in the ECoG. These findings provide evidence that vinpocetine may serve as a useful therapeutic agent in diseases characterized by cerebral deficits.
Optical applications of silicon micromachining technology

To implement optical submodules or systems of the future we have identified a few key components and technologies necessary to build optical products at Hewlett Packard. To be competitive these optical assemblies must be smaller, cheaper and more functional, then current optical products while maintaining or exceeding the existing performance level. To accomplish this task we introduce the idea of a silicon micro- optical bench (SMOB). The focus of the micro-optical bench has been laser submounts and collimators. However, while making advances in these platform technologies, the importance of micro parts which can be used to augment and expand the optical functions has become apparent. In this paper the role of silicon as a micro-optical bench substrate is described along with implementations of micro-optical benches. Silicon is an excellent choice as a base platform for SMOB technology because of its availability and excellent material properties and advanced processing technology. Structures to aid in batch assembly processes are easily constructed from silicon wafers. We show how to create structures which allow placement of ball lenses and other three dimensional structures to 1 micrometer accuracy. This can be accomplished in a batch process with the potential for reductions in cost of assembly. We have built generic laser submounts and collimators with various sizes of ball lenses. We show how the performance of these submounts agrees with the theoretical predictions. For fiber to ball coupling Gaussian methods work well. However, for laser to fiber coupling via ball lenses it is necessary to use a Maxwell equation solver in spherical coordinates to correctly predict the spherical aberration effects. The ball lenses can collect the laser light with great efficiency at a fraction of the cost for convectional GRIN or aspheric lenses. Furthermore, the small size allows the whole optical part to fit within standard hermetic packages.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Quartz crystal size distribution of the Ordovician Millbrig K-bentonite

Abstract Crystal size distribution (CSD) analysis has been applied to quartz crystals of the Ordovician Millbrig K-bentonite, which represents one of the largest known fallout ash deposits in the Phanerozoic Era, to establish crystal growth histories and conditions in the magma chamber prior to eruption. Specific CSDs were examined for crystal growth conditions. All Millbrig samples exhibit lognormal concave-down shapes in agreement with previously reported CSDs on large silicic systems but in contrast to more mafic systems characterized by linear CSDs. Concave-down CSDs are possibly an intrinsic property of phenocryst growth in large volume silicic magmas as documented in the literature [Bindeman, I.N., 2003. Crystal sizes in evolving silicic magma chambers. Geology, 31: 367–370.]. Quartz crystals of the Millbrig must have been produced by surface-controlled, size-dependent growth with a minor Ostwald ripening component, which could have easily changed to supply-controlled growth due to a limited supply of nutrients, as the crystals grew larger. CSDs were also used to examine the possible origin of multiple ash beds in the Millbrig. These ash beds appear to be a product of a series of separate eruptions that represent separate magma layers or batches, each with slightly different crystal growth conditions.
Nasty or Nice?: Political Systems, Endogenous Norms, and the Treatment of Adversaries

A large amount of recent research points to the importance of domestic political institutions in shaping foreign policy, most of it turning on the distinction between democratic and nondemocratic regimes. However, fundamental characteristics differentiate regime types beyond the distinction between democratic and nondemocratic. Drawing a distinction between institutional differences that result from variation in the sizes of selectorates and winning coalitions, the authors consider the effect that regime type has on the prospects that a foreign leader will be removed from office following a military defeat, be it in a war or some lesser level of violence. The authors show that the distinction, now common in the literature, between democratic and nondemocratic regimes is not adequate for understanding the linkages between domestic and foreign affairs. A model is presented from which nine hypotheses are derived. A preliminary test of one hypothesis is presented, the results of which are consistent with the ...
Bispectral index in dogs anesthetized with isoflurane: comparison with sevoflurane.

Bispectral index (BIS) is a numerical value derived from the EEG that is used clinically by anesthesiologists to assess CNS depression in human beings. In a previous study, canine BIS values were inversely related to end-tidal sevoflurane (SEVO) concentration: BIS = 102.7 − (14.2 × [SEVO]); R2 = 0.754. The purpose of this study was to determine the relationship between BIS and end-tidal isoflurane (ISO) in the same dogs used in the SEVO study. ISO minimum alveolar concentration (MAC) was determined using the tail-clamp technique for six English pointer dogs (three males and three females) with a mean ± SD age and weight of 3.7 ± 2.0 years and 20.2 ± 4.8 kg, respectively. One week after MAC determination, BIS was measured at 0.8, 1.0, 1.5, and 2.0 MAC multiples of ISO. Ventilation was controlled and atracurium (0.2 mg kg−1 followed by 6 µg kg−1 minute−1 IV) was administered to eliminate EMG artefact from the EEG. The BIS was determined using an A-2000 monitor (Aspect Medical Systems Inc.). After a 15-minute equilibration period, BIS data were collected for 5 minutes and median BIS values were calculated. Heart rate, direct mean arterial blood pressure (MAP), esophageal temperature, and arterial blood gases were measured at each BIS collection period. End-tidal CO2 and percentage [ISO] were monitored using a calibrated infra-red gas analyzer. Data were analyzed using RM anova (p < 0.05). The mean ISOMAC value was 1.3 ± 0.2%. The BIS values were inversely related to [ISO]: BIS = 93.9 − (25.2 × [ISO]); R2 = 0.614. Mean ± SD BIS values at 0.8, 1.0, 1.5, and 2.0 MAC were 65 ± 8, 60 ± 7, 52 ± 3, and 15 ± 27, respectively. At 2 MAC, three dogs had burst suppression that prevented reliable BIS determination. The BIS values were significantly higher during SEVO at 0.8 and 1.0 MAC compared to ISO. Minor, yet statistically significant, differences between and within anesthetic groups were observed for cardiovascular and arterial blood gas data. We conclude that a predictive relationship exists between BIS and end-tidal [ISO]. However, BIS correlated with end-tidal [SEVO] better than with [ISO]. The BIS appears to be somewhat agent dependent in this group of six dogs. Clinical use of BIS monitoring in dogs may require evaluation of specific anesthetic drug combinations.
Nanoscale properties of melting at the surface of semiconductors

In this study, we use density-functional simulations to investigate how nanoscale surface coatings can alter the melting dynamics of semiconductor surfaces. We demonstrate that a single-monolayer coating of GaAs can dramatically reduce the diffusive motion of the surface atoms of a Ge(110) crystal and cause superheating of the bulk at temperatures well above the Ge melting point on the 10 ps time scale. In direct contrast, a single-monolayer coating of Ge will induce surface melting of a GaAs(110) structure 300 K below the GaAs melting point. We also identify a metallization of the band structure and bond alterations in the charge density near the melting transition. In addition, we suggest that the Ge monolayer causes the GaAs(110) surface to melt through transient penetration of the Ge atoms into the bulk, which locally initiates the collective diffusive motion of large groups of Ga and As atoms. These studies on the effect of coatings in semiconductors clearly point to the surface material as the dominant determinant of the melting characteristics of a hybrid structure. These simulations have important implications for high-temperature materials design while simultaneously probing the fundamental features of the melting transition.
Analysis of disinfection data from dilution count experiments

Abstract When disinfection experiments are conducted using dilution count methods (e.g. MPN tests or animal infectivity assays), inactivation parameters may be assessed in three distinct ways. First, the density of survivors may be determined by MPN tables and two-step linear regression (or “eyeball”) methods used to estimate Chick-Watson parameters. Second, the survivor density vs concentration and time may be used in a non-linear least squares procedure to estimate inactivation parameters. Third, a maximum likelihood estimation in which the actual numbers of positive and negative tubes as a function of experimental conditions and sample volume may be executed. Using Monte Carlo simulation, it is determined that the third method is optimal (in terms of bias and standard error) for Poisson, or nearly Poisson error distribution. For more overdisperse error structure, however, nonlinear regression performs more satisfactorily. An empirical test of overdispersion is proposed as a diagnostic tool for assessing the optimum method for data analysis.
Electrical Double-Layer Effects on the Brownian Diffusivity and Aggregation Rate of Laponite Clay Particles

Dynamic light scattering was used to study the Brownian translational diffusion and rate of Brownian aggregation of Laponite (RD) clay particles at low (millimolar) electrolyte concentrations. Laponite is a manufactured clay consisting of monodisperse disk-shaped particles with a 30-nm diameter and a 1-nm thickness. The stability ratio, defined as the ratio of the coagulation rate for Brownian spheres with no particle interactions to the observed coagulation rate, was quite large O(10(5)), suggesting that there was a large potential energy barrier to Brownian aggregation. The apparent potential energy barrier for face-edge aggregation was rationalized on the basis of a calculation of the electrostatic interactions between two disks with negative face charges and positive rim charges. The aggregation rate increased with increasing electrolyte concentration owing to the screening of the electrostatic repulsion associated with the net charge on the particle. The rate decreased with increasing pH because of the decreasing positive charge on the rim. The translational diffusivity of the individual particles before the onset of aggregation exhibited a strong dependence on the electrolyte concentration and was as much as 50% smaller than the diffusivity for an uncharged disk. This effect is attributed to the added drag resulting from the electroviscous effects in the deformed double layer. The electroviscous effect on the diffusion of the disk-like particles is much stronger than that on rods and spheres. Copyright 2001 Academic Press.
Carbon cycling in the upper waters of the Sargasso Sea: I. Numerical simulation of differential carbon and nitrogen fluxes

Abstract A complex ecosystem model is developed for the area around Bermuda in the Sargasso Sea. The model is physically driven by seasonal changes in spectral light, temperature, and water column mixing. Autotrophic growth is represented by four functional groups of phytoplankton. The groups have light and nutrient utilization characteristics that reflect those of Prochlorococcus , Synechococcus and Chromophycota species. The model includes differential carbon and nitrogen cycling, nitrification, and nitrogen fixation to effect realistic allochthonous and autochthonous nutrient sources to the euphotic zone. This simulation yields realistic seasonal and vertical (1) succession of phytoplankton functional groups’ biomass, productivity, and pigments; (2) profiles of dissolved inorganic carbon, nitrate, and ammonium; and (3) fluxes of carbon dioxide at the air–sea boundary and particulate carbon and nitrogen settling losses, when compared to the JGOFS BATS site. The addition of local nitrification, differential carbon and nitrogen remineralization, and nitrogen fixation removes the need for an unrealistically high upward vertical flux of nitrate to mimic the productivity and chlorophyll a stocks. The explicit numerical description of carbon and nitrogen utilization by heterotrophic bacteria simulated a population that was not nitrogen-limited in these waters. Instead, the heterotrophic bacteria community was limited by energy resources in the form of DOC, and was a nitrogen source for the autotrophic community through the excretion of excess NH 4 from the labile DOM energy source. Numerical descriptions of ecosystems based solely on nitrogen dynamics, or fixed carbon to nitrogen ratios, may yield an inaccurate prediction of carbon and nitrogen fluxes, and fail to properly predict the carbon cycle.
Effective learning and feedback to designers through design and wafer inspection integration

As design rules continue to shrink beyond the lithography wavelength, pattern printability becomes a significant challenge in fabrication for 45nm and beyond. Model-based OPC and DRC checkers have been deployed using metrology data such as CD to fine-tune the model, and to predict and identify potential structures that may fail in a manufacturing environment. For advanced technology nodes with tighter process windows, it is increasingly important to validate the models with empirical data from both product and FEM wafers instead of relying solely on traditional metrology and simulations. Furthermore, feeding the information back to designers can significantly reduce the development efforts.
A look to the future of animal clinical biochemistry: Implications for diagnostics and research

The changing environment in the medical biochemistry arena as a result of new and concerted pressures for cost containment will have and is having its inevitable effect on the field of animal clinical biochemistry. The animal clinical biochemist must be acutely aware of the changes engendered by these pressures and be prepared to respond in a meaningful way. First and foremost, the animal clinical biochemist must be positioned as a scientist with a unique capability to cross disciplinary lines as befits the needs to understand interspecies nuances. As a corollary, there is a need for the animal clinical biochemist to not only keep abreast of new developments but to be a generator of new knowledge in the field. This then implies that research and dissemination of new knowledge is an inherent responsibility of those in the field. In this way, the animal clinical biochemist is positioned as an independent scientist/principal investigator in a broad range of studies involving animals. This further implies that animal clinical biochemists must broaden their knowledge of clinical medicine to be able to converse freely in the “language of medicine”. Numerous new vistas are described and which can be exploited to advance the field and the scope of activities for animal clinical biochemists. Among these are the Point-of-Care systems, new approaches to diabetes management, thyroid disease, autoimmune disease and tumour markers. The list of additional areas is extensive; markers of inflammation, markers of nutritional disease or deficiency, DNA probes in inherited disease, DNA probes of infectious disease. All of these areas are ripe for new ideas and advances in knowledge needing only the imaginative efforts of the animal clinical biochemist.
The Measurement of Light Scattered by the Upper Atmosphere from a Search-Light Beam

Rayleigh scattering from atmospheric gases in the path of an intense search-light beam has been measured up to heights of 34 km. It is found that above a limit of haze, which varies on different days from four to ten km, the scattering agrees with that calculated upon the assumption of the usual atmosphere. Clouds have been occasionally observed at heights of 12 km. It is shown that the method can be extended to allow measurements up to heights of 70 to 90 km and to determine the distribution of ozone at low altitudes, as well as the study of other atmospheric problems.
A Qualitative Study of Incarcerated Mothers' Perceptions of the Impact of Separation on Their Children

Many incarcerated women are mothers, and their children exhibit various responses to the separation that incarceration commands. This exploratory qualitative study examines incarcerated women's perceptions of the consequences of their illegal activity, confinement, and separation from their children on their offspring. The results indicate that although mothers are concerned about their children, they are typically unable to recognize the negative consequences of their actions on their children and their relationship with their children until beginning intensive treatment. Effective treatment must focus on the woman's personal issues along with their parenting abilities and skills to repair these relationships and promote healthy family functioning.
Viewing community as responsibility as well as resource: deconstructing the theoretical roots of psychological sense of community

The field of scholarship surrounding the construct of psychological sense of community (PSOC) has been dominated by first-order learning processes attending to issues of measurement and prediction of the four-dimensional framework proposed by McMillan and Chavis (1976). This article seeks to contribute to the conceptual development of PSOC by clarifying the second-order assumptions of PSOC as it is represented in prevailing conception and measurement. We introduce human needs theory as a macro framework for representing the definition and study of PSOC to date. Second, we illuminate the limitations of a purely needs theory perspective of PSOC and propose the value of exploring alternative theoretically grounded perspectives. Third, we offer an alternative theoretical base for PSOC—a sense of community as responsibility—and highlight how this alternative theoretical lens can suggest new models for understanding the dynamic between PSOC, psychological well-being, and community engagement. © 2010 Wiley Periodicals, Inc.
A Continuously Operating, Flux Locked, Superfluid Interferometer

We report the characteristics of a flux locked, superfluid 4He interferometer that can continuously measure time-varying rotation rates. We describe the principles underlying the interferometer, including the dynamics of a superfluid chemical potential battery used to obtain continuous operation. We also discuss noise and drift issues and their possible amelioration.