cssi/SciSciGPT-SciSciNet huggingface dataset:
Learning Political Engagement from the Experts: Advocacy Groups, Neighborhood Councils, and Constituency Service

This article describes an uncommon approach to service learning. To dem onstrate points of access to the political system, I place students in my class with experts of the political advocacy process, not with charitable nonprofits. And to reach a wide spectrum of students, I inte grate the service-learning component in one section of the basic American and state government course, which is a gen eral education requirement for all college graduates in the state of California. This report explains the approach, evaluates the course based on student responses, identifies reasons for its success, and points out some of the limits encoun tered. The article follows the tradition of Battistoni (2000), Battistoni and Hudson (1997, 1), Zlotkowski (1998), and others by sharing insights into the theory and practice of service learning in political science, in the hopes of making transpar ent the advantages and limits of this form of experiential learning.1 After an activist start in the 1960s and 1970s, service learning in more recent years has, to a great extent, evolved into charitable work, as the testimonies by pioneers indicate (Stanton, Giles, and Cruz 1999) and the Campus Compact (2002a; 2003; 2004) surveys have docu mented. High school and college students are asked to volunteer in nonprofit orga nizations to help needy children and adults. That is the "service" part of the service-learning mission. In political sci ence courses, the instructor introduces the "learning" component by asking the students to reflect on the causes of pov erty or other deficiencies, to study the public policies that alleviate or fail to resolve the problems, and to devise strat egies of advocacy on behalf of the needy. Service learning is different than in ternships, even though the activities can overlap. Internships are intended to pre pare students for their future career and to provide some work experience. In contrast, the goal of service learning is citizenship education: to prepare young people for a responsible role as citizens, as well as to generate a sense of commu nity with social groups the students might otherwise not interact with. My wish to introduce students at the California State University, Los Angeles (CSULA) to political institutions that may be beyond the students' cognitive horizon has been the central reason for pursuing the service-learning project de scribed in this article. The project intro duces students to three pathways citizens have to influence the political process and governmental action:
Real-time modeling of primitive environments through wavelet sensors and Hebbian learning

Modeling the world through sensory input necessarily provides a unique perspective for the observer. Given a limited perspective, objects and events cannot always be encoded precisely but must involve crude, quick approximations to deal with sensory information in a real- time manner. As an example, when avoiding an oncoming car, a pedestrian needs to identify the fact that a car is approaching before ascertaining the model or color of the vehicle. In our methodology, we use wavelet-based sensors with self-organized learning to encode basic sensory information in real-time. The wavelet-based sensors provide necessary transformations while a rank-based Hebbian learning scheme encodes a self-organized environment through translation, scale and orientation invariant sensors. Such a self-organized environment is made possible by combining wavelet sets which are orthonormal, log-scale with linear orientation and have automatically generated membership functions. In earlier work we used Gabor wavelet filters, rank-based Hebbian learning and an exponential modulation function to encode textural information from images. Many different types of modulation are possible, but based on biological findings the exponential modulation function provided a good approximation of first spike coding of `integrate and fire' neurons. These types of Hebbian encoding schemes (e.g., exponential modulation, etc.) are useful for quick response and learning, provide several advantages over contemporary neural network learning approaches, and have been found to quantize data nonlinearly. By combining wavelets with Hebbian learning we can provide a real-time front-end for modeling an intelligent process, such as the autonomous control of agents in a simulated environment.
Interferon gamma (IFN-γ) production by gut-associated lymphoid tissue and spleen following oral Salmonella typhimurium challenge

Abstract Although IFN-γ has been shown to play an important role in protection against a systemic S. typhimurium challenge, the in vivo and in vitro production of this cytokine following S. typhimurium infection of the gastrointestinal tract has not been investigated. In this study, IFN-γ production by gut-associated lymphoid tissue and spleen was investigated in mice following oral challenge with S. typhimurium . Cells obtained from the Peyer's patches (PP), mesenteric lymph nodes (MLN) and spleen (Sp) of mice orally challenged with S. typhimurium were assessed for levels of IFN-γ mRNA after varying times following in vivo infection. RNA obtained from the above tissues was subjected to reverse transcription followed by PCR amplification using primers specific for murine IFN-γ. Elevated levels of IFN-γ mRNA were first detected in the PP at 6 h post-challenge. Elevated levels of IFN-γ mRNA were then detected in the MLN at 24 h and in the spleen at 4 days post-challenge. These in vivo results were in agreement with the ability of these lymphoid tissues to produce IFN-γ upon in vitro stimulation with killed S. typhimurium . Neutralization of endogenously produced IFN-γ by administration of mAb to IFN-γ completely abrogated resistance to an oral challenge of S. typhimurium . A significant difference in the percent mortality was observed between the antibody-treated and control groups. Evaluation of bacterial spread in the antibody treated group versus the control group at 4 days following oral challenge revealed higher numbers of bacteria in the spleen and liver of antibody treated mice. These results clearly show that IFN-γ is rapidly produced by gut-associated lymphoid tissue and spleen following oral S. typhimurium infection, and that endogenous production of IFN-γ is essential in host resistance to S. typhimurium .
Liquid and Solid Wastes from Mineral Processing Plants

Abstract Many liquid and solid substances, inorganic and organic, can be discharged from mineral processing plants. Many of these substances are toxic and must be either removed from various streams or rendered non toxic. Proper recycling of water and/or proper placement of wastes can reduce waste disposal problems. Remediation methods for liquid wastes and substances dissolved in water or other liquids includes the proper use of tailings ponds, use of solids reduction or removal processes, flocculation of fine solids, base or acid addition, precipitation and co-precipitation of metals from solution, adsorption, bioremediation methods, flotation, and oxidation/reduction processes. Proper solids disposal depends usually on the proper construction and management of tailings impoundments. Agglomeration and other physical binding treatment of solids are potential aids in the disposal of reactive wastes such as those containing sulfides. These various technologies are discussed and listings are made of approxi...
Computer Simulation of the Surface Free Energy of the Si(100) Surface and the Line Free Energies Associated with Steps on This Surface

Many atomic-level 0 K thermodynamic properties of silicon (100) surfaces have been calculated from classical potential energy surfaces or from quantum ground-state Born−Oppenheimer surfaces. We present an easy and accurate computer simulation method for determining surface thermodynamic properties at high temperatures where the dynamics may be described classically. The method is illustrated with calculations of the surface free energies of the 2 × 1 and c(2 × 2) reconstructed (100) surfaces at T = 1000 K using the Stillinger−Weber interaction model for silicon. We then use an extension of our simulation method to determine the line free energies associated with steps. Enough examples of line free energies are given to enable us to calculate the equilibrium concentration of single and double steps as a function of the surface miscut angle. We also deduce the activation free energy associated with the Si adatom hopping over simple steps.
Effects of lead structure in Bering Sea pack ice on the flight costs of wintering spectacled eiders

Abstract In polar regions, sea ice is critical habitat for many marine birds and mammals. The quality of pack ice habitat depends on the duration and spacing of leads (openings in the ice), which determine access to water and air for diving endotherms, and how often and how far they must move as leads open and close. Recent warming trends have caused major changes in the extent and nature of sea ice at large scales used in climate models. However, no studies have analyzed lead structure in terms of habitat for ice-dependent endotherms, or effects of climate on ice habitat at scales relevant to their daily movements. Based on observations from an icebreaker and synthetic aperture radar (SAR) images, we developed methods to describe the dynamics and thermodynamics of lead structure relative to use by spectacled eiders ( Somateria fischeri ) wintering in pack ice of the Bering Sea. By correlating lead structure with weather variables, we then used these methods to estimate changes in lead dynamics from 1945 to 2002, and effects of such changes on flight costs of the eiders. For 1991–1992, when images were available about every 3 days throughout winter, SAR images were divided among five weather regimes defined by wind speed, wind direction, and air temperature. Based on 12.5-m pixels, lead shape, compass orientation, and fetch across leads did not differ among the weather regimes. However, the five regimes differed in total area of open water, leads per unit area, and distance between leads. Lead duration was modeled based on air temperature, wind, and fetch. Estimates of mean daily flight time for eiders, based on lead duration and distance between neighboring leads, differed among regimes by 0 to 15 min. Resulting flight costs varied from 0 to 158 kJ day −1 , or from 0% to 11% of estimated field metabolic rate. Over 57 winters (1945–2002), variation among years in mean daily flight time was most influenced by the north–south wind component, which determined pack divergence (lead opening) during northerly winds or pack convergence (lead closing) during southerly winds. Mean daily flight time and flight cost during winter did not differ among proposed periods of decadal-scale climate shifts in the North Pacific Ocean. Although leads in mobile pack ice constantly open and close with variations in wind, under most conditions in the Bering Sea there appeared to be a shifting-mosaic steady-state of lead availability. Long-term trends in the extent and timing of Bering Sea pack ice may have affected spectacled eiders more by altering foodweb processes than by changing flight costs relative to lead structure.
Strategic Industrial Sourcing: The Japanese Advantage

The article reviews the book “Strategic Industrial Sourcing: The Japanese Advantage,” by Toshihiro Nishiguchi.
Heavy Duty Truck Fuel Consumption Prediction Based on Driving Cycle Properties

ABSTRACT A methodology originally developed to predict vehicle emissions was applied to prediction of fuel consumption for 56 over-the-road heavy-duty trucks recruited in southern California. The method employed measurements exercised over chassis dynamometer cycles and the properties of those cycles. Nine driving cycle properties and their combinations were used to predict fuel consumption over an “unseen” cycle, based on measurements from up to four different baseline driving cycles. The results showed that the use of average velocity and average positive acceleration was suitable for the translation of fuel consumption between cycles, producing the lowest prediction error among the cases considered.
Onset of 310-Helical Secondary Structure in Aib Oligopeptides Probed by Coherent 2D IR Spectroscopy

We have investigated the onset of the secondary structure and the evolution of two-dimensional infrared (2D IR) spectral patterns as a function of chain length with a study of 310-helical peptides. The results show that 2D IR is highly sensitive to peptide conformation, disorder, and size. An extensive set of 2D IR spectra of Cα-methylated homopeptides, Z-(Aib)n-OtBu (n = 3, 5, 8, and 10), in CDCl3 was measured in the amide-I region. The 2D spectral patterns of the tripeptide are quite different from those of the longer peptides. The spectral signatures begin to converge at the pentapeptide and become almost the same for the octa- and decapeptide. Simulations employing a vibrational exciton model were performed, with the local mode frequency shifts estimated from the intramolecular hydrogen bond electrostatic energies. The 2D spectra are well simulated using dihedral angle distributions around the average values (ϕ, ψ) ≈ (−57°, −31°) with a width of ∼21°. The simulated site-dependent amide-I local mode fr...
Design and Analysis of Transmission Spline and Key Profiles

Splines and keys are machinery components placed at the interface between shafts and hubs of power-transmitting elements. A spline (or key) is usually machined (or attached) onto the shaft of a power-transmitting pair, and the corresponding groove is cut into the hub. The influence of spline profiles on the performance of power transmission is investigated in this paper. The optimal design of spline profiles for three different design criteria is presented. The method of calculus of variation is used to determine profile functions for maximum value. Analytical results are successfully obtained. They show that the splines with involute profiles lead to uniform deformation on the hub, in addition they can carry the maximum transmission load capacity. On the other hand radial straight profiles result in optimum transmission efficiency. We think that these findings are worthy reporting and also believe that this approach could be used for the spline design with other performance criteria imposed.Copyright © 2005 by ASME
Effects of random fluctuations in ply mechanical properties on ultrasound propagation in a laminated solid layer

Abstract One-dimensional ultrasound propagation across a laminated solid layer which has alternating plies of two different materials is investigated. The velocities of the longitudinal wave in the ply materials are assumed to have random fluctuations from their mean values. The Furstenberg theorem and Monte Carlo simulation are employed to study the effects of the random fluctuations on the ultrasound propagation. It is shown that because of the random fluctuations, there is an exponential decay in the amplitude of the transmission coefficient at all frequencies, which increases with increasing frequency. Physically, the exponential decay is caused by the random fluctuations in the phase terms of the transfer matrices.
Nonalcoholic Fatty gallbladder disease: the influence of diet in lean and obese mice.

The obesity epidemic has contributed to an increased prevalence of gallstones and a higher percentage of chronic acalculous cholecystitis. Obesity is associated with Type II diabetes and hyperlipidemia in murine models. In addition, we have previously demonstrated that serum glucose, insulin, cholesterol, and triglycerides correlated with gallbladder contractility in murine models. However, the relative role of in sulin resistance and gallbladder fat infiltration in this phenomenon remain unclear. Therefore, we tested the hypothesis that gallbladder wall lipids are related to obesity and diet and are inversely correlated with gallbladder contractility. One hundred lean control (C7BL/6J) and 36 obese leptin-deficient (Lepob) 8-week-old female mice were fed either a chow diet or a 1.0% cholesterol, 15% butterfat (high-lipid) diet for four weeks. Pooled gallbladders were then analyzed for free fatty acids (FFA), phospholipids (PL), total cholesterol (TC), and triglycerides (TG). Cholesterol/phospholipid ratios were then calculated. The Lepob mice fed a chow diet had significantly higher (P<0.01) gallbladder lipids than the three other groups. The lean mice that were fed a high-lipid diet had increased (P<0.05) gallbladder TC compared to the lean mice on a chow diet. In addition, the cholesterol/phospholipid ratio was significantly in creased (P<0.01) in the lean mice fed a high-lipid diet compared to the other three groups. Finally, the high-lipid diet decreased gallbladder FFA (P<0.01), PL (P=0.08), and TC (P<0.05) in Lepob mice. These data suggest that (1) obese mice have increased gallbladder lipids; (2) a high-cholesterol, high-fat diet increases gallbladder lipids and the cholesterol/phospholipid ratio in lean mice; but (3) de creases gallbladder fatty acids, phospholipids, and cholesterol in obese mice. Prior studies have docu mented similarly decreased gallbladder response to neurotransmitters in obese mice on a chow diet, as well as lean and obese mice on a high-lipid diet. Therefore, we conclude that leptin-deficient obesity and/or a high-fat diet causes nonalcoholic fatty gallbladder disease, which is manifested by diminished gallbladder contractility.
PARTIAL MAINTENANCE OF THE ADRENAL CORTEX BY ANTERIOR PITUITARY GRAFTS IN FED AND STARVED GUINEA PIGS

Considerable interest has centered about the question of the nature of the stimulus to the anterior pituitary gland which leads to the release of adrenocorticotrophic hormone (Long, 1947; Sayers and Sayers, 1948). There are two phases to this problem; first, the stimulus which results in the release of adrenocorticotrophin in the normal animal and maintains adrenal cortical function at customary levels; and second, the stimulus which mobilizes the additional trophic hormone needed rapidly during conditions of stress in which there is increased utilization of cortical hormone. The mechanisms involved are not necessarily the same. Uotila (1939) and Dempsey and Searles (1943) have shown that whereas section of the hypophyseal stalk in the rat does not interfere with maintenance of the thyroid, the release of extra thyrotrophin in response to cold which occurs in the intact rat is absent in the stalk-sectioned animal.
Diffusion-weighted imaging in the evaluation of watershed hypoxic-ischemic brain injury in pediatric patients

The purpose of our study was to determine the usefulness of echo-planar diffusion-weighted imaging (EPDI) in the evaluation of watershed hypoxic-ischemic brain injury in pediatric patients. Eighteen patients ranging in age from 3 weeks to 12 years were evaluated for evidence of ischemic/infarction changes on conventional MR and EPDI. Included in the study group were five patients with sickle cell disease, four with congenital heart disease, four with hypotensive episodes with various etiologies, three with sepsis, and two with encephalitis or meningitis. Patients were examined 2 h to 6 days after the initial insult, with follow-up studies in four patients at 1 to 62 days after the initial examination. After conventional MR imaging (T1, FSE T2, and FLAIR), diffusion-weighted MR imaging was performed using high-speed, single-shot EP techniques with TR 6000, TE 144, matrix 96 × 128, FOV 23.3 × 31 and five b values of 0, 160, 360, 640, and 1,000 s/mm2. EPDI demonstrated abnormally increased signal in watershed ischemic/infarction zones in all initial cases. Apparent diffusion coefficients (ADC) were obtained in 59 lesions. When compared with radiographically normal (on EPDI) contralateral brain parenchyma, 45 demonstrated a relatively decreased ADC, while eight had normal ( ± 10 %) and six had increased ADC. In four cases, signal abnormalities on EPDI were not seen or exceeded that seen with conventional MR imaging. In the remaining cases, signal abnormalities were obvious on EPDI and more subtle on conventional MR imaging. Follow-up studies demonstrated resolution of abnormal EPDI signal with persistent abnormalities on conventional imaging in some cases, while others revealed an increase in size or number of EPDI signal abnormalities, suggesting ongoing acute ischemic/infarctive changes. EPDI is a rapid, sensitive technique for detecting watershed ischemic/infarction changes in pediatric patients with hypoperfusion episodes, at times before such changes are apparent on conventional MR images and/or are clinically apparent.
A legendre technique for solving time-varying linear quadratic optimal control problems

Abstract A method for the optimal control of linear time-varying systems with a quadratic cost functional is proposed. The state and control variables are expanded in the shifted Legendre series, and an algorithm is provided for approximating the system dynamics, boundary conditions and performance index. The necessary condition of optimality is then derived as a system of linear algebraic equations. Numerical examples are included to demonstrate the validitiy and applicability of the technique.
Foraging Behavior of the Blue Morpho and Other Tropical Butterflies: The Chemical and Electrophysiological Basis of Olfactory Preferences and the Role of Color

Inside a live butterfly exhibit, we conducted bioassays to determine whether the presence of color would facilitate the location of attractants by the butterflies. It was found that color facilitated odor attraction in some species that feed on flowers (Parthenos silvia, Heraclides thoas, Dryas julia, and Idea leuconoe), but not in the exclusively fruit-feeding species, such as Morpho helenor, hence demonstrating that species with different natural diets use different foraging cues. Green, ripe, and fermented bananas were evaluated for their attractiveness to butterflies together with honey and mangoes. The fermented bananas were determined to be the most attractive bait, and the electrophysiological responses to their volatiles were studied in Morpho helenor and Caligo telamonius. During GC-EAD evaluation, fifteen different aliphatic esters, such as isobutyl isobutyrate, butyl acetate, ethyl butanoate, and butyl butanoate (both fermentation products and fruit semiochemicals) were shown to be detected by the butterflies’ sensory apparatus located in the forelegs, midlegs, proboscis, labial palpi, and antennae. Legs, proboscis, and antennae of Morpho helenor and Caligo telamonius showed similar sensitivity, reacting to 11 chemicals, while labial palpi had a lower signal-to-noise ratio and responded to seven chemicals, only three of which produced responses in other organs.
Magnetic Field Effects on Bubble Growth in Boiling Liquid Metals

A theoretical analysis of bubble growth in superheated liquid metals shows that in the presence of a strong magnetic field, the growing bubble would assume an elongated shape and the volume would be less than that for the nonmagnetic case. As time progresses and for higher field strengths the bubble becomes more elongated. The analytical results are used to estimate the effect of strong magnetic fields on nucleate boiling heat transfer.
Does the Fact that a Client has Failed to Provide Requested Information Predict Severity of Suicidal Thinking?: A Criterion Validity Study of Missing Client Information

A study was conducted to investigate the validity of missing information on a client background questionnaire as an indicator of suicidal thinking. Method: Four hundred six responses on a client background questionnaire and on the Multi-Problem Screening Inventory were obtained and analyses conducted to test the relationship between missing client information on the background questionnaire and the severity of suicidal ideation. Results: Results suggested that missing information on education, income, and/or number of persons living with the respondent were valid indicators of the severity of suicidal thinking and that the relationship between depression and severity of suicidal ideation, and between aggression and severity of suicidal ideation, may be stronger for clients who fail to report their income than for those who do. Conclusion: Missing information on intake forms may be useful as both an early screening tool for suicidal thinking and as important information when conducting in-depth suicide ris...
DNA structure: evidence from electron microscopy

The contour lengths of phiX174 DNA duplex and RNA-DNA hybrid molecules were measured by several commonly used electron microscopic techniques. The countour length of the hybrid molecules corresponds to a rise of 2.5 to 2.6 angstroms per base pair, as expected for the A conformation, while the length of phiX174 duplex DNA similarly measured corresponds to a 2.9-angstrom rise, very different from 3.4 angstroms of the classic B form. Thus any chromatin structure parameter based on electron microscopy and a rise of 3.4 angstroms must be reappraised. The possibility that DNA in dilute solution also has a rise of 2.9 angstroms and a screw of 10.5 base pairs per turn is discussed.
A Carboxyl-terminal Domain Controls the Cooperativity for Extracellular Ca2+ Activation of the Human Calcium Sensing Receptor: A STUDY WITH RECEPTOR-GREEN FLUORESCENT PROTEIN FUSIONS *

Abstract Calcium sensing receptors are part of a growing G protein-coupled receptor family, which includes metabotropic glutamate, γ-aminoisobutyric acid, and pheromone receptors. The distinctive structural features of this family include large extracellular domains that bind agonist and large intracellular, carboxyl-terminal domains of as yet undefined function(s). We have explored the contribution(s) of the carboxyl terminus of the human calcium sensing receptor (CaR) by assessing extracellular Ca2+-mediated changes in intracellular Ca2+ in individual HEK-293 cells transfected with CaR clones. In-frame fusion of EGFP to the carboxyl terminus of CaR had no effect on either the dose response for extracellular Ca2+ activation or CaR desensitization. Carboxyl-terminal truncations, fused in-frame with EGFP (CaRΔ1024-EGFP, CaRΔ908-EGFP, CaRΔ886-EGFP, and CaRΔ868-EGFP), were assessed for alterations in Ca2+-dependent activation or desensitization. Significant effects on the dose-response relation for extracellular Ca2+ were observed only for the CaRΔ868 truncation, which exhibited a decreased affinity for extracellular Ca2+ and a decrease in the apparent cooperativity for Ca2+-dependent activation. The alterations in extracellular Ca2+ affinity and cooperativity observed with CaRΔ868 were recapitulated by a point mutation, T876D, in the full-length CaR-EGFP background. All truncations with wild type dose-response relations exhibited desensitization time courses that were comparable to the full-length CaR, whereas the CaRΔ868 receptor desensitized completely after two exposures to 10 mmCa2+. Interestingly, the CaR point mutation T876D exhibited desensitization comparable to wild type CaR, suggesting that this mutation specifically modifies CaR cooperativity. In conclusion, these studies suggest that amino acid residues between 868 and 886 are critical to the apparent cooperativity of Ca2+-mediated activation of G proteins and to CaR desensitization.
A randomized, double-blind, placebo-controlled study of verapamil and metoprolol in treatment of multifocal atrial tachycardia

Purpose Multifocal atrial tachycardia is a difficult arrhythmia to treat. Patients not showing a response to the correction of predisposing conditions present a therapeutic dilemma. To assess the efficacy of two agents reported to be effective in this condition, verapamil, metoprolol, or placebo was given intravenously in a randomized, doubleblind trial. Patients and methods Thirteen patients meeting inclusionary criteria were enrolled. Therapeutic response was defined as conversion to sinus rhythm, a decline in the ventricular rate of 15 percent or less, or a ventricular rate of less than 100 beats/minute. Four male and nine female patients having a mean age (± SD) of 81.9 ± 14.2 years were enrolled. Automated serum chemistries, complete blood cell count with differential, arterial blood gas values, and serum digoxin and theophylline levels were determined and a 12-Iead electrocardiogram was obtained at the start of the trial. Following the completion of each phase of the study, a repeat physical examination was performed, andarterial blood gas values and an electrocardiogram were obtained. The trial was designed to run for two days. Results Two of 10 (20 percent), four of nine (44 percent), and eight of nine (89 percent) showed a response to placebo, verapamil, or metoprolol, respectively. Mean slowing of ventricular rate was 3.4, 7.3, and 24.5 percent for placebo, verapamil, and metoprolol, respectively (p Conclusion We conclude that metoprolol appears to be more effective than verapamil in treating multifocal atrial tachycardia. However, careful patient selection is necessary in its use.
The effect of temperature on rapid dark adaptation in bullfrog photoreceptors--a difference between rods and cones.

Abstract The late receptor potential of the perfused bullfrog retina was isolated with sodium-aspartate. Rapid dark adaptation of the rods and of the cones was monitored independently of one another. In rods, decreasing the temperature both increased the latency of onset of rapid dark adaptation and decreased the rate of adaptation following onset. In cones, only the latency of onset of adaptation was found to be temperature dependent. We conclude that both the latency and recovery phases of the adaptation are enzymatically mediated in rods, but that in cones the actual recovery phase is dependent mainly on diffusion. The mechanistic basis of these observations is discussed.
AN IN SITU IMINIUM FORMATION-ALLYLATION APPROACH TOWARDS THE 1-AZA-4.5.0-SPIROBICYCLIC CORE OF HALICHLORINE AND PINNAIC ACID

Abstract A facile procedure for the formation and allylation α to the nitrogen of 1-azaspirobicyclic systems has been developed. In examining an approach towards the synthesis of the natural products halichlorine ( 1 ) and pinnaic acid ( 2 ), spontaneous condensation of an aldehyde-carbamate to form a spirobicyclic N -acylenamine was observed. Introduction of the C1–C5 moiety of the natural products was then initiated in a one pot procedure involving acid mediated enamine-imine conversion and treatment with allytrimethylsilane. This resulted in essentially a single diastereomeric product, which was determined to correspond to the C5 epimer of 1 and 2 .
Sequences in the Cratonic Interior of North America

The concept of major rock-stratigraphic units of interregional scope was introduced in 1948 (Longwell, 1949). It is now possible to restate the concept and to define more explicitly the sequences delimited by interregional unconformities in the continental interior of North America. The sedimentary record of the North American craton from late Precambrian to present is characterized by six major unconformities. These interregional unconformities subdivide the cratonic stratigraphic column into six sequences—major rock-stratigraphic units (of higher than group, megagroup, or supergroup rank) which can be identified, where preserved, in all cratonic interior areas. At the cratonic margins the bounding unconformities tend to disappear in continuous successions, and the cratonic sequences are replaced by others controlled by events in the marginal basins and eugeosynclinal borders. Although the time values of the unconformities vary widely because of differences in degree of nondeposition and amount of erosion, the approximate dates of the regressional maxima represented are: (1) very late Precambrian, (2) early Middle Ordovician, (3) early Middle Devonian, (4) “post-Elvira” Mississippian, (5) early Middle Jurassic, and (6) late Paleocene. A seventh major regression is now in progress.
Monoclonal antibody defines determinant between Theiler's virus and lipid-like structures.

Theiler's murine encephalomyelitis virus is known to cause a chronic demyelinating disease in mice. The contributions of immunologic factors, i.e. humoral and cellular responses to virus and/or myelin components, and direct virus-cell interactions leading to demyelination are still unclear. One important factor could be antibody initiation of myelin destruction. Here we describe four monoclonal antibodies that react with Theiler's murine encephalomyelitis virus. Three of these neutralize the virus and one of these three could also bind to various lipid-like structures including galactocerebroside, a myelin component. Further, this monoclonal antibody reacted with oligodendrocyte-like cells in vitro. All four monoclonal antibodies reacted with VP-1 by Western blot analysis. Thus, an immune response generated by virus that cross-reacts with a myelin element such as galactocerebroside could play a role in directing autoimmune processes toward myelin destruction.
Syncope with abrupt termination of exercise.

We describe a patient who had syncope after jogging. Extensive evaluation including stress testing using the Bruce protocol with sudden cessation of exercise did not reveal a specific cause of syncope. Performing ambulatory monitoring while the patient did his usual jogging activity revealed multiple sinus arrests as a cause of syncope
Molecular dynamics simulation studies on Ca2+-induced conformational changes of annexin I

Cryo-electron microscopy (EM) and X-ray studies proposed different mechanisms for annexin-induced membrane aggregation. In this work, molecular dynamics (MD) simulation technique was utilized to gain an insight into the calcium-induced conformational changes on annexin I and their implication in membrane aggregation mechanism. MD simulations were performed on the Ca2+ -free annexin I with the N-terminal domain buried inside the core (System 1), the Ca2+ -bound annexin I without N-terminal domain (System 2) and the Ca2+ -bound annexin I with the N-terminal domain exposed (System 3). Our results indicated that calcium binding increases the flexibility of annexin I core domain residues including the calcium coordinating residues. As a result, annexin I was activated to interact with the negatively charged membrane. The exposed N-terminal domain was very flexible and gradually lost the secondary structure during MD simulation, suggesting that the N-terminal may adopt a favorable conformation to bind a second membrane and also explaining the failure of attempts to crystallize the full-length annexin I in the presence of calcium ions. The measured dimensions of the averaged simulation structure of the Ca2+ -bound annexin I with the N-terminal exposed (System 3) support the proposed membrane aggregation mechanism based on X-ray studies.
A Framework for Profile Similarity: Integrating Similarity, Normativeness, and Distinctiveness

Many questions in personality psychology lend themselves to the analysis of profile similarity. A profile approach to issues such as personality judgment, personality similarity, behavioral consistency, developmental stability, and person-environment fit is intuitively appealing. However, it entails conceptual and statistical challenges arising from the overlap among profile similarity and normativeness, which presents potential confounds and potential opportunities. This article describes the normativeness problem, articulating the need to evaluate profile similarity alongside normativeness and distinctiveness. It presents conceptual and psychometric foundations of a framework differentiating these elements for pairs of profiles. It derives two models from this framework, and it discusses the application of their components to a variety of research domains. Finally, it presents recommendations and implications regarding the use of these components and profile similarity more generally. This approach can reveal and manage potential confounds, and it can provide theoretical insights that might otherwise be overlooked.
Design and evaluation of a two-stage, cyclic, recombinant fermentation process

A two-stage, cyclic fed-batch fermentation process to produce recombinant human lymphokine was designed. The organism used in the study was Escherichia coli K-12 containing a temperature-sensitive walkaway plasmid bearing an insert which codes for a human lymphokine. Transcription of the recombinant gene is controlled by a lambda repressor/pL promoter system. The lambda promoter is regulated by the temperature-sensitive product of the cl857 gene at 30°C, but at 42°C the promoter is derepressed. The first or growth, stage of the process was maintained at 28°C and operated in the fed-batch mode. The vessel was fed at a rate which gives a constant specific growth rate using a media designed to maintain a constant optical density OD600 of 50. After the volume in the first stage reached the maximum working volume of the vessel (12 L), a portion of the vessel contents was transferred to the second stage. The second, or induction/product formation, stage also operated in the fed-batch mode, was kept at 42°C, and was fed with a media that is conducive to recombinant human lymphokine synthesis. An optical density of more than 100 was consistently achieved in the second stage. Thirty cycles were completed with a consistent yield of human lymphokine and cell density in each cycle. The process was used to produce 200 L of OD600 50 material from the first stage in 10 days. The volumetric productivity (g lymphokine/L. day) of the two-stage, cyclic fed-batch process is twice that of a single-stage, fed-batch fermentation process.
Combinatory effect of fluconazole and FDA-approved drugs against Candida albicans

Candida albicans is the primary cause of systemic candidiasis, which has a high mortality rate. Unfortunately, the number of antifungal drugs available for treatment of Candida infections is limited, and there is an urgent need for development of new drugs and alternative therapeutic options. We investigated the combinatory effect of fluconazole (FLCZ) and 640 FDA-approved drugs in vitro. Ten drugs enhanced and 77 drugs attenuated the antifungal activity of FLCZ. Other drugs did not appear to alter the antifungal activity of FLCZ, although 17 drugs displayed potency equivalent to or greater than that of FLCZ. The 10 FLCZ-enhancing drugs included three inhibitors of 3-hydroxy-3-methyl-glutaryl-CoA reductase, whose synergistic activity had been reported previously. However, the antifungal effects of 3 FLCZ enhancers—artesunate, carvedilol, and bortezomib—were previously unknown. In addition, many drugs were found to attenuate the antifungal activity of FLCZ, including 17 cyclooxygenase (COX) inhibitors, 15 estrogen-related agents, vitamin A- and D-related compounds, antihypertensive drugs, and proton pump inhibitors. Although the clinical significance remains to be determined, analyses of molecular events responsible for synergy or antagonism could provide insight into more efficient use of existing antifungals and lead to novel therapies.
RhoGDIα downregulates androgen receptor signaling in prostate cancer cells.

INTRODUCTION Treatment of primary prostate cancer (CaP) is the withdrawal of androgens. However, CaP eventually progresses to grow in a castration-resistant state due to aberrant activation of androgen receptor (AR). Understanding the mechanisms leading to the aberrant activation of AR is critical to develop effective therapy. We have previously identified Rho GDP Dissociation Inhibitor alpha (GDIα) as a novel suppressor in prostate cancer. In this study, we examine the effect of GDIα on AR signaling in prostate cancer cells.
Biophysical and pharmacological characterization of voltage-gated calcium currents in turtle auditory hair cells.

Hair cell calcium channels regulate membrane excitability and control synaptic transmission. The present investigations focused on determining whether calcium channels vary between hair cells of different characteristic frequencies or if multiple channel types exist within a hair cell, each serving a different function. To this end, turtle auditory hair cells from high- (317 ± 27 Hz) and low-frequency (115 ± 6 Hz) positions were voltage clamped using the whole-cell recording technique, and calcium currents were characterized based on activation, inactivation and pharmacological properties. Pharmacological sensitivity to dihydropyridines (nimodipine, Bay K 8644), benzothiazepines (diltiazem) and acetonitrile derivatives (verapamil, D600) and the insensitivity to non-L-type calcium channel antagonists support the conclusion that only L-type calcium channels were present. Fast activation rise times (< 0.5 ms), hyperpolarized half-activation potentials and a relative insensitivity to nimodipine suggest the channels were of the α1D (CaV1.3) variety. Although no pharmacological differences were found between calcium currents obtained from high- and low-frequency cells, low-frequency cells activated slightly faster and at hyperpolarized potentials, with half-activating voltages of −43 ± 1 mV compared to −35 ± 1 mV. Inactivation was observed in both high- and low-frequency cells. The time course of inactivation required three time constants for a fit. Long depolarizations could result in complete inactivation. The voltage of half-inactivation was −40 ± 2 mV for high-frequency cells and −46 ± 2 mV for low-frequency cells. Calcium channel inactivation did not significantly alter hair cell electrical resonant properties elicited from protocols where the membrane potential was hyperpolarized or depolarized prior to characterizing the resonance. A bell-shaped voltage dependence and modest sensitivities to intracellular calcium chelators and external barium ions suggest that inactivation was calcium dependent.
Ontogenetic Mechanisms Underlying a Geographic Size Cline in a Grasshopper, Romalea microptera

ABSTRACT Geographic clines in body size have been described for many species, but relatively few investigations have tested hypotheses for the ontogenetic mechanisms maintaining geographic clines. We formalize and test the predictions for the role of ontogenetic mechanisms (e.g., hatching timing and size, juvenile developmental time, juvenile growth rate) in maintaining a longitudinal cline in adult body size of lubber grasshoppers [Romalea microptera (Beauvois)]. To obtain hatching timing and size, we collected eggs from wild females from several populations along the longitudinal gradient in 2 yr (2006 and 2007) and measured hatchling size and hatch date. To obtain juvenile developmental time and growth rates, we surveyed populations along the longitudinal gradient during 2 yr (2006 and 2007) and estimated developmental time and growth rates. We found the developmental time (hatching to fourth instar) and female growth rates increase from west to east along the cline. Patterns of hatching timing and hat...
Species–energy relationships and habitat complexity in bird communities

Species–energy theory is a commonly invoked theory predicting a positive relationship between species richness and available energy. The More Individuals Hypothesis (MIH) attempts to explain this pattern, and assumes that areas with greater food resources support more individuals, and that communities with more individuals include more species. Using a large dataset for North American birds, I tested these predictions of the MIH, and also examined the effect of habitat complexity on community structure. I found qualitative support for the relationships predicted by the MIH, however, the MIH alone was inadequate for fully explaining richness patterns. Communities in more productive sites had more individuals, but they also had more even relative abundance distributions such that a given number of individuals yielded a greater number of species. Richness and evenness were also higher in structurally complex forests compared to structurally more simple grasslands when controlling for available energy.
The symbiotic ion channel homolog DMI1 is localized in the nuclear membrane of Medicago truncatula roots.

Summary Legumes utilize a common signaling pathway to form symbiotic associations both with rhizobial bacteria and arbuscular mycorrhizal fungi. The perception of microbial signals is believed to take place at the plasma membrane, activating a cascade that converges on the nucleus where transcriptional reprogramming facilitates the symbioses. Forward genetic strategies have identified genes in this signaling pathway including Medicago truncatula DMI1 3 (Doesn’t Make Infections 1) that encodes a putative ion channel. Although the DMI1 homologs from Lotus japonicus, CASTOR and POLLUX, were recently reported to be localized in plastids, we report here that a functional DMI1::GFP fusion is localized to the nuclear envelope in M. truncatula roots when expressed both from a constitutive 35S promoter and from a native DMI1 promoter. Localization may be mediated in part by sequences located within the amino-terminus of DMI1. This region of DMI1 is required for symbiotic signal transduction 4 , and its replacement with a bona fide plastid transit peptide from the glutamine synthetase 2 gene does not restore DMI1 function. These new data place DMI1 in the nuclear envelope in close proximity to the origin of Nod 5 -factor-induced calcium spiking.
Survey of unified switching techniques for integrated-service networks

The authors survey proposals for future integrated-service networks, with emphasis on unified approaches which employ a single switching technique across the entire network bandwidth. It is noted that the two most promising unified approaches are burst and fast packet switching. Burst switching is a circuit switching-based approach which allocates channel bandwidth to a connection only during the transmission of bursts of information. Fast packet switching is a packet switching-based approach which can be characterized by very high transmission rates on network links and simple, hardwired protocols which match the high bandwidth of the network. Both approaches are proposed as possible implementations for integrated-service networks. The authors also briefly examine N-ISDN (narrowband integrated services digital network), and discuss the key performance issues found in fast packet switching. >
Recognition of methylated peptides by Drosophila melanogaster polycomb chromodomain.

Lysine methylation is one of the important post-translational modifications (PTMs) that regulate protein functions. Up to now, proteomic identification of this PTM remains a challenge due to the lack of effective enrichment methods in mass spectrometry experiments. To address this challenge, we present here a systematic approach to predicting peptides in which lysine residues may be methylated to mediate protein� protein interactions. We used the chromodomain of the polycomb protein in Drosophila melanogaster as a model system to illustrate the success of this approach. We started with molecular dynamics simulations and free energy analyses on the histone peptides complexed with the polycomb chromodomain to understand how the binding specificity is achieved. We next conducted virtual mutagenesis to quantify each domain and peptide residue's contribution to the domain-peptide recognition, based on which scoring scheme was developed to evaluate the possibility of any lysine-containing peptides to be methylated and recognized by the chromodomain. A peptide microarray experiment on a panel of conserved histone peptides showed a satisfactory prediction accuracy of the scoring scheme. Next, we implemented a bioinformatics pipeline that integrates multiple lines of evidence including conservation, subcellular localization, and mass spectrometry data to scan the fly proteome for a systematic identification of possible methyllysine-containing peptides. These putative chromodomain-binding peptides suggest unknown functions of the important regulator protein polycomb and provide a list of candidate methylation events for follow-up investigations.