cssi/SciSciGPT-SciSciNet huggingface dataset:
Measuring Treatment Effects with Big N Panels

This paper considers the problem of estimating treatment effects when there is a large number of potential control units. The paper introduces to the economics literature the idea of polytope volume minimization as a method of estimating a factor model when observed outcomes are assumed to be a convex combination of the unobserved factor values. The paper shows that this method is particularly well-suited to the case where there are a large number of cross-sectional units. The paper presents identification results for both exact and approximate factor models which are new to the literature. It presents simulations that compare standard methods such as difference-in-difference and synthetic controls to the proposed approach. The estimator is used to estimate the effect of reunification on German growth rates.
Palimpsestic pedagogies: Mapping fascist violence against children from Mussolini’s dictatorship to present day Italy

This essay focuses on the disavowed histories of Italy’s fascist past with a specific focus on how select historical disavowals reverberate in the present through the law of restricted citizenship,...
Relative influences of microhabitat incubation conditions and genetic parentage effects on lake sturgeon (Acipenser fulvescens) offspring traits during early ontogeny

Knowledge on factors influencing traits during critical early growth periods is essential for predicting population persistence. Genetic effects and microhabitat stream conditions at female selected oviposition sites influence larval phenotypes. However, limited work has examined contributions of both factors across sequential ontogenetic stages for larvae of wild origin. Using a wild population of lake sturgeon (Acipenser fulvescens) from Black Lake, Michigan (USA), fertilized eggs were collected from stream substrate just prior to hatch at one-meter intervals along seven transect lines at an adult-selected spawning area. Microhabitat variables (depth, discharge, substrate size) were recorded at egg collection points. Body length, body area, and yolk-sac area were quantified for yolk-sac larvae (N = 359) at the time of hatch. Following the onset of exogenous feeding, larval growth was measured weekly for four weeks. Parentage was assigned using genetic-based analysis. Inter-individual variation in phenotypic traits quantified at hatch were attributed to stream microhabitat variables; mean depth had the largest influence. No additive genetic effects were detected at hatch. Post-emergence larval growth significantly varied within and among half-sibling groups with the greatest range in body size observed at 33 days post-hatch. Additive genetic variance and heritability increased with age. Results demonstrate that female-selected incubation habitats influenced traits at hatch for wild-origin fish, but effects do not persist to a sequential ontogenetic stage. Alternatively, growth after the onset of exogenous feeding was largely influenced by intrinsic (genetic) factors which must be considered when designing and implementing rehabilitation strategies for lake sturgeon and potentially other threatened riverine fishes.
Bacterial exposure leads to variable mortality but not a measurable increase in surface antimicrobials across ant species.

Social insects have co-existed with microbial species for millions of years and have evolved a diversity of collective defenses, including the use of antimicrobials. While many studies have revealed strategies that ants use against microbial entomopathogens, and several have shown ant-produced compounds inhibit environmental bacterial growth, few studies have tested whether exposure to environmental bacteria represents a health threat to ants. We compare four ant species' responses to exposure to Escherichia coli and Staphylococcus epidermidis bacteria in order to broaden our understanding of microbial health-threats to ants and their ability to defend against them. In a first experiment, we measure worker mortality of Solenopsis invicta, Brachymyrmex chinensis, Aphaenogaster rudis, and Dorymyrmex bureni in response to exposure to E. coli and S. epidermidis. We found that exposure to E. coli was lethal for S. invicta and D. bureni, while all other effects of exposure were not different from experimental controls. In a second experiment, we compared the antimicrobial ability of surface extracts from bacteria-exposed and non-exposed S. invicta and B. chinensis worker ants, to see if exposure to E. coli or S. epidermidis led to an increase in antimicrobial compounds. We found no difference in the inhibitory effects from either treatment group in either species. Our results demonstrate the susceptibility to bacteria is varied across ant species. This variation may correlate with an ant species' use of surface antimicrobials, as we found significant mortality effects in species which also were producing antimicrobials. Further exploration of a wide range of both bacteria and ant species is likely to reveal unique and nuanced antimicrobial strategies and deepen our understanding of how ant societies respond to microbial health threats.
Scenario creation and power-conditioning strategies for operating power grids with two-stage stochastic economic dispatch

A significant difficulty associated with the use of stochastic programming to solve optimal power flow problems on a 5-minute timescale is the quality of renewable energy scenarios input by the user. This is especially true when considering power systems with high penetrations of renewable energy, e.g. wind power. This paper introduces the use of stochastic programming to solve the DC optimal power flow problem with scenarios drawn directly from high-fidelity data sets. Hence, the proposed method avoids the problem of lost physics by finding high-fidelity analogs that can describe future states of the system. Furthermore, this method can be simply extended to output multi-period scenarios to the stochastic program. We demonstrate the effectiveness of this technique by simulating dispatch operations on a synthetic test system over the course of a week.
The privilege of childcare: an intersectional analysis of the COVID-19 U.S. childcare crisis and its implications for CAM research

With daycare centers and schools closed due to social distancing mandates enacted to control the spread of COVID-19, most children have been home for the pandemic. The closure of schools has tasked...
Multiparameter continuation methods for tracking desired flow states

Conventional means of continuation and critical point tracking have been adapted for two novel applications: the tracking of onset of separation at a boundary, and of the limiting conditions for pinning of a static contact line at an edge. The method presented applies more generally to tracking flow states under constrained variation of parameters; the only difference from one application to another is the choice of constraints. Because this choice is virtually limitless, it is believed that the method could have wide utility in computational fluid mechanics and other systems modeling, whether for scientific or for technological purposes.
Accelerating Kinodynamic RRT* Through Dimensionality Reduction.

Sampling-based motion planning algorithms such as RRT* are well-known for their ability to quickly find an initial solution and then converge to the optimal solution asymptotically. However, the convergence rate can be slow for highdimensional planning problems, particularly for dynamical systems where the sampling space is not just the configuration space but the full state space. In this paper, we introduce the idea of using a partial-final-state-free (PFF) optimal controller in kinodynamic RRT* [1] to reduce the dimensionality of the sampling space. Instead of sampling the full state space, the proposed accelerated kinodynamic RRT*, called Kino-RRT*, only samples part of the state space, while the rest of the states are selected by the PFF optimal controller. We also propose a delayed and intermittent update of the optimal arrival time of all the edges in the RRT* tree to decrease the computation complexity of the algorithm. We tested the proposed algorithm using 4-D and 10-D state-space linear systems and showed that Kino-RRT* converges much faster than the kinodynamic RRT* algorithm.
A National Assessment of the Association Between Patient Race and Physician Visit Time During New Outpatient Urology Consultations.

Abstract Objective To determine if there is an association between patient race and physician time spent with the patient during outpatient urology consultations. Methods We identified all adult urology new outpatient visits in the National Ambulatory Medical Care Survey dataset for 2012-2016. Patient race was dichotomized as White or non-White. Our primary outcome was time spent during the visit between the patient and urologist. Using population-level weighting, we compared differences in mean time spent during visits with White and non-White patients. Mixed-effects linear regression was used to adjust for confounding factors and to account for clustering among individual physicians. Secondary outcomes included number of services provided and if ancillary providers were seen. Results Over the 5 year period, 1668 raw visits met criteria and were used to estimate 21million new outpatient urology visits nationwide. 80% of all visits were with White patients. Mean physician time spent among visits with white patients was 23.9 minutes and 24.4 minutes for non-White patients. There was no difference in number of services provided but visits with non-white patients were less likely to include an ancillary provider. After adjustment, there was no significant difference in mean time spent with the urologist among visits with White and non-White patients (difference 0.9 minutes, 95% CI: -0.6-2.4). There were also no differences in adjusted mean time spent among return visits or new visits for hematuria, urologic cancers, or BPH. Conclusion We found no statistically significant difference in time spent with a urologist during outpatient office consultations between White and non-White patients.
The Nature of the Genetic Mechanism

Now that the preceding chapters have viewed the actions of the molecular genetic mechanism through the development, differentiation, and functioning of mature organisms, several observations concerning the nature of the actual genetic processes become obvious that remained obscure or completely concealed when only the macromolecular (Dillon, 1978a) and cellular levels (Dillon, 1981) had been examined. But, as becomes evident in the following discussion, even at those lower levels of biological organization, some important features had actually been disclosed in those analyses but in too intangible form to be expressed in words. In a sense, then, this closing chapter of the present study is designed to serve as a summary for the entire trilogy.
Shock Tunnel Operation and Correlation of Boundary Layer Transition on a Cone in Hypervelocity Flow

The Caltech T5 reflected shock tunnel is used to produce hypervelocity flow over a range of velocities and pressures by varying the test gas and operating parameters of reservoir enthalpy (hres) and reservoir pressure (Pres). One area of research in T5 is the measurement of boundary layer behavior and transition from laminar to turbulent flow on a smooth 5-degree half-angle cone [3, 1, 11].
Embryonic tissues as elasticoviscous liquids: II. Direct evidence for cell slippage in centrifuged aggregates

Abstract Certain embryonic cell aggregates display both solid-like and liquid-like properties in organ culture. When centrifuged against solid substrata, these aggregates undergo sudden initial deformations followed by more gradual shape changes. Thus, they are either compoundviscoelastic solids (in which cells first stretch rapidly, then slowly) or elasticoviscous liquids (in which cells first quickly stretch, but then gradually slide by one another). To distinguish between these alternatives, we have examined cell shapes in centrifugally deformed chick liver aggregates. Light and electron micrographs show that initially stretched cells within flattening aggregates gradually reassume their original undisturbed shapes during prolonged centrifugation. Therefore, although the cells themselves may react to stretching forces like elastic solids, they slowly slip past one another within aggregates to relax stretching forces, endowing the aggregates with liquid properties. Slow cell slippage can account not only for temporary elastic solidity and viscous liquid flow in cell aggregates, but also for stress-free changes in the positions and configurations of tissues migrating within developing embryos. Regulation of cell slippage properties may shift the morphogenetic dependence of embryonic tissues in successive developmental stages from intracellular to intercellular force-generating mechanisms, or vice versa.
Multiple Forms of Yeast Phosphoglucose Isomerase I. RESOLUTION OF THE CRYSTALLINE ENZYME INTO THREE ISOENZYMES

Abstract Crystalline phosphoglucose isomerases isolated from brewers' and from bakers' yeast have each been resolved into three isoenzyme fractions. The separate identity of the isoenzymes has been demonstrated analytically by electrophoresis on cellulose acetate at pH 4.7, 5.2, and 6.5. Separation on a preparative scale has been achieved by column chromatography on diethylaminoethyl cellulose with a sodium phosphate gradient at pH 6.0. The following points were investigated in order to establish the origin of the multiple forms of the enzyme. Crystalline phosphoglucose isomerases isolated from three yeast species were all found to contain three isoenzyme fractions. The chromatographic procedure itself was shown not to be responsible for the appearance of the different protein fractions. Conditions known to favor possible proteolysis neither altered the qualitative behavior of the isoenzymes nor changed the relative amounts of isoenzymes found after chromatographic separation. Three isoenzymes were also found in a phosphoglucose isomerase preparation crystallized after isolation from a live, genetically homogeneous yeast culture, thus excluding the possibility that in the dried yeast the existence of several isoenzymes might be explained by assuming genetically mixed strains. All results obtained support the conclusion that the isoenzymes exist in vivo and that they are not artifacts of the purification procedures.
James Madison: The (Unknown) Great Communicator

When he became president in 1809, James Madison faced formidable challenges. Restrictions on foreign trade, supported by Madison and Thomas Jefferson as the means to keep the U.S. out of war with France and England, were unpopular and ineffective. Diplomatic efforts to resolve the international disputes were faltering, and actual conflict seemed increasingly likely. To help manage these problems, Madison used his presidential newspaper, the National Intelligencer, to influence public opinion at home and signal his intentions to governments abroad. The newspaper published numerous letters from Madison to citizen groups in which he defended his positions, and regularly carried commentaries that were known to have been authored by Madison and key members of his administration. These commentaries were widely understood in diplomatic circles to be stating the latest foreign policy positions of the U.S., and were acted upon accordingly by foreign governments. The paper analyzes the ways in which public communication played a crucial but largely overlooked role in Madison’s presidency as he tried to project his executive authority at home and abroad.
Release of pseudorabies virus from infected cells is controlled by several viral functions and is modulated by cellular components.

The role of the nonessential glycoproteins gI, gp63, and gIII in the release of pseudorabies virus from different cell lines was investigated. We show that these glycoproteins may have a beneficial or deleterious effect on virus release depending on the type of cell in which the virus is grown. Inactivation of the genes encoding either gI, gp63, or gIII has no detectable effect on virus release from rabbit kidney cells. Inactivation of gI or gp63 strongly promotes virus release from chicken embryo fibroblasts, whereas inactivation of gIII reduces virus release from these cells. A defect in both gI and gIII or in both gp63 and gIII diminishes virus release from rabbit kidney cells but improves release from chicken embryo fibroblasts. We demonstrate that all three nonessential glycoproteins contribute to one specific aspect of viral growth, namely, virus release, and that they affect virus release in conjunction with each other. Furthermore, our results show that the manifestation of the role of each of these viral functions in virus growth may differ in different cell types, i.e., that release is affected by these viral functions in conjunction with some unknown cellular function.
Refined understanding of perspectives on employee‐organization relationships: Themes and variations

Purpose – This paper aims to explore the perceptions of organizational members about employee‐organization relationships (EOR) under the globalization context.Design/methodology/approach – The study used 58 qualitative interviews with both managers and employees in multinational and domestic companies in China.Findings – First, the unique features of employee publics determined the nature of EOR (why and how an EOR was established) and EOR was a multi‐level (interpersonal and organizational) and multi‐dimensional (job and task related vs human and benefits oriented) concept for most organizational members. Second, the outcomes of EOR, especially trust, control mutuality, and commitment were also determined by the multi‐dimensional nature of EOR. Finally, the influencing factors on EOR can be classified into three levels: individual (such as types of employees, styles of top management), organizational (such as developmental stages and types of organizations), and macro‐environmental (such as the overall e...
Antioxidant properties of quercetin.

Quercetin, a plant-derived aglycone form of flavonoid glycosides, has been used as a nutritional supplement and may be beneficial against a variety of diseases, including cancer. We examined the antioxidant properties of quercetin. The reduction potential of quercetin was measured at various pH values using voltammetric methods, and its total antioxidant capacity (TAC) was measured using the phosphomolybdenum method. The effect of quercetin on production of reactive oxygen species (ROS) and nitric oxide (NO) in LPS-stimulated human THP-1 acute monocytic leukemia cells was determined by flow cytometry using CM-H2DCFDA dye. The results were compared with curcumin, a natural product exhibiting a similar range of reported health benefits. Results: 1) Quercetin has a higher reduction potential compared with curcumin at three different pH settings and is comparable to Trolox at pH 7-9.5; 2) its TAC is 3.5 fold higher than curcumin; 3) it reduced LPS-induced ROS to near normal levels; 4) it reduced LPS-induced NO production. These data provide a physico-chemical basis for comparing antioxidants, with potential benefits individually or in combination.
Efficient propositional constraint propagation

We present an efficient method for inferring facts from a propositional knowledge base, which is not required to be in conjunctive normal form. This logically-incomplete method, called propositional fact propagation, is more powerful and efficient than some forms of boolean constraint propagation. Hence, it can be used for tractable deductive reasoning in many AI applications, including various truth maintenance systems. We also use propositional fact propagation to define a weak logical entailment relation that is more powerful and efficient than some others presented in the literature. Among other applications, this new entailment relation can be used for efficiently answering queries posed to a knowledge base, and for modeling beliefs held by a resource-limited agent.
Social stigma and its consequences for the socially stigmatized.

This paper presents an integrative review of current and classic theory and research on social stigma and its consequences for the socially stigmatized. Specific attention is paid to stigma-related processes surrounding race/ethnicity, gender, and sexual orientation. The origins and perpetration of social stigma are discussed alongside perspectives on how stigmatized groups and individuals experience stigma-related stress. Consideration is given to responses to stigma in the form of coping, social support, and meaning-making processes. Both the potential negative and positive consequences of social stigma are highlighted in this review through the integration of predominant social psychological theory with emerging critical and feminist theories of positive marginality and resistance. The paper culminates in a theoretical process model designed to provoke future theory and research that share its integrative aims. © 2011 The Author. Social and Personality Psychology Compass © 2011 Blackwell Publishing Ltd.
A Dual Vacuum Chamber Fourier Transform Mass Spectrometer with Rapidly Interchangeable LSIMS, MALDI, and ESI Sources: Initial Results with LSIMS and MALDI

A design is presented involving two separate vacuum chambers to provide nearly simultaneous capabilities of liquid secondary ion mass spectrometry (LSIMS), matrix-assisted laser desorption/ionization (MALDI), and electrospray ionization (ESI) in an external source Fourier transform mass spectrometer. The instrument consists of two vacuum chambers, one with five stages of differential pumping for a combined LSIMS/MALDI source. The chamber dedicated to ESI was formerly a three-stage chamber with LSIMS and electron ionization. Two additional stages were added with the ESI source. LSIMS and MALDI have similar vacuum requirements and were moved to a newly built chamber with two stages of pumping. We present our first results obtained on the new vacuum chamber. Data presented for the MALDI source show that, with only two stages of pumping, and with shorter radio frequency-only quadrupole rods for ion injection, spectra comparable to those obtained on the formerly three-stage instrument can be obtained. Characterization of the MALDI source and data on linear, cyclic, and branched oligosaccharides are given. Finally, the design of the secon chamber is proposed as a low-cost prototype for an external source FTMS instrument.
Polymer-Dispersed Liquid Crystal Films For Light Control Applications

Polymer-dispersed liquid crystal (PDLC) films, comprised of liquid crystal microdroplets dispersed in polymer matrices, are attractive for a variety of indoor and outdoor light control applications since they can be switched electrically from a light-scattering off-state to a transparent on-state. This paper reviews the electro-optic properties of PDLC films which govern their performance in such diverse applications as electronic information displays, signs, room dividers, and solar energy control in buildings and automobiles. Factors governing the operating temperature range of PDLC films will be identified and temperature-dependent transmittance and response-time characteristics of these films will be presented. Spectral transmittance characteristics will be discussed and used to determine contrast ratios of PDLC films. Dual frequency addressing of PDLC films will be demonstrated and shown to be a viable technique for increasing contrast ratio of PDLC displays. Solar attenuation properties of PDLC films will be reviewed.
On adaptive inverse dynamics control of rigid robots

The authors derive an adaptive inverse dynamics control law for rigid robots that overcomes the most restrictive difficulty of such schemes to date, namely, the requirement that the inverse of the estimated inertia matrix remain bounded. The control scheme still requires the joint accelerations for its implementation. In practice, one would implement this scheme by estimating the acceleration from the measured velocity. Good performance could still be expected without direct acceleration measurement, assuming sufficient encoder resolution and sufficiently fast sampling. Another practical advantage of the authors' scheme is that since the 'nominal' inverse dynamics or inner loop portion of their control law is fixed, it is more amenable to the development of a dedicated interface and can be 'burned' onto a chip to reduce online computation requirements. >
A derivation of a rote learning curve from the total uncertainty of a task

The derivation of H. D. Landahl’s learning curve (1941,Bull. Math. Biophysics,3, 71–77) from a single information-theoretical assumption obtained previously (Rapoport, 1956,Bull. Math. Biophysics,18, 317–21) is extended to obtain the entire family of such curves with the number of stimuliM (to each of which one ofN responses is to be associated) as a parameter. No additional assumptions are required. The entire family thus appears as a function of a single free parameter,k, all other parameters being experimentally determined. The theory is compared with a set of experiments involving the learning of artificial languages. An alternative quasi-neurological model leading to the same equation is offered.
The covalent binding of d-fructose 1,6-diphosphate to muscle aldolase

Abstract Rabbit muscle aldolase was reduced with sodium borohydride (or cyanoborohydride) in the presence of specifically labeled [3H]- and [14C]fructose 1,6-diphosphate. Under steady-state conditions, about 10–15% of the specific ϵ-lysine catalytic sites were bound to fructose 1,6-diphosphate by a covalent ketimine linkage. The remaining substituted lysine residues were identified as N6-β-glyceryllysine. The results argue against a concerted mechanism of binding and cleavage of fructose 1,6-diphosphate by type I aldolases.
Robotics for computer scientists: what’s the big idea?

Modern robots, like today’s smartphones, are complex devices with intricate software systems. Introductory robot programming courses must evolve to reflect this reality, by teaching students to make use of the sophisticated tools their robots provide rather than reimplementing basic algorithms. This paper focuses on teaching with Tekkotsu, an open source robot application development framework designed specifically for education. But, the curriculum described here can also be taught using ROS, the Robot Operating System that is now widely used for robotics research.
Superconducting Cosmic Strings

Recent theoretical results on the physics of superconducting cosmic strings (SCSs) are reviewed, with a focus on their implications for the role of SCSs in the early universe. Topics addressed include the basis of string theory in particle physics, string electrodynamics, SCS interactions with plasma, the astrophysical effects of a primordial magnetic field, astrophysical effects without a magnetic field (for light, intermediate, and superheavy SCSs), and the probability of existence of SCSs (estimated as about 25 percent). 24 refs.
Vaginal Douching Among Latinas: Practices and Meaning

Objectives Vaginal douching is widely practiced by American women, particularly among minority groups, and is associated with increased risk of pelvic and vaginal infections. This research sought to investigate vaginal hygiene practices and meaning associated with them among Latina women and adolescents. Study results would guide development of an intervention to decrease douching among Latinas. Methods In depth qualitative interviews conducted with English- and Spanish-speaking women aged 16–40, seeking care for any reason who reported douching within the last year (n = 34). Interviews were audiotaped, transcribed and analyzed using qualitative methods. One-third of interviews were conducted in Spanish. Results Two explanatory models for douching motives emerged: one stressed cosmetic benefits; the other, infection prevention and control. Most women reported douching to eliminate menstrual residue; a small number reported douching in context of sexual intercourse or vaginal symptoms. Many were unaware of associated health risks. Respondents typically learned about douching from female family members and friends. Male partners were described as having little to no involvement in the decision to douche. Women varied in their willingness to stop douching. Two-thirds reported receiving harm reduction messages about “overdouching”. About half indicated previous discussion about douching with health care providers; some had reduced frequency in response to counseling. A number of previously unreported vaginal hygiene practices and products were described, including use of a range of traditional hygiene practices, and products imported from outside the US. Conclusions Respondents expressed a range of commitment to douching. Counseling messages acknowledging benefits women perceive as well as health risks should be developed and delivered tailored to individual beliefs. Further research is needed to assess prevalence and safety of previously unreported practices.
25Gb/s hybrid silicon switch using a capacitively loaded traveling wave electrode.

We demonstrate a hybrid silicon modulator and switch operating up to 25 Gb/s with over 10 dB extinction ratio. The modulator has voltage-length product of 2.4 V-mm while the switch has switch time less than 35 ps and crosstalk smaller than −12 dB.
Storage Effects on Dielectric Properties of Eggs from 10 to 1800 MHz

The dielectric constant and loss factor of egg albumen and egg yolk over the frequency range from 10 to 1800 MHz were measured at 24 ◦ Ca tw eekly intervals during 5-wk storage at 15 ◦ C. Moisture and ash contents of albumen and yolk, as well as Haugh unit and yolk index, were also measured. The dielectric constant and loss factor of albumen were higher than those of yolk. Linear relationships were evident between the log of frequency, below about 1000 MHz, and the log of loss factor of albumen as well as that of yolk. The dielectric constants of albumen and yolk at 10 MHz were lower than those of fresh albumen and yolk when eggs were stored at 15 ◦ C for 1 wk. However, after 2 wk in storage these dielectric constants rose and remained at higher levels for the rest of the 5-wk period. At frequencies of 100 MHz and higher, the dielectric constant was essentially constant during the entire storage period. Storage had much less influence on the loss factor of either albumen or yolk. In general, the moisture content and ash content of albumen and yolk decreased slightly as eggs aged. The moisture content of yolk increased somewhat with storage, and there was a corresponding decrease in albumen moisture content. The freshness qualities, Haugh unit and yolk index, also decreased as eggs aged. No obvious correlation between dielectric properties and moisture content, ash content, Haugh unit, or yolk index was observed.
Myeloma and carcinoma metastatic to bone

In three equal groups of cases (57 each of myeloma, carcinoma of the breast, and other carcinoma) with bone lesions, the radiographs were scrutinized for the prevalence of various diagnostic signs. No sign pathognomonic of myeloma was found. Preservation of pedicles, despite erosion or collapse in vertebral bodies; significant expansion of bone; and well-defined areas of destruction in the skull; are all strongly suggestive of myeloma. A soft-tissue mass associated with a rib lesion is uncommon when the primary tumour is in the breast but with other carcinomas is as common as in myeloma. Increased bone density is less common in myeloma than in carcinoma but is occasionally seen.
Application of the carbonyl epoxide rearrangement to the formation of dioxabicycloalkanes and alkenes. Synthesis of the mus musculus pheromone.

Abstract Acid-catalyzed intramolecular opening of epoxides by carbonyl groups provides a general stereocontrolled method for forming dioxabicyclo systems, including the (±)- Mus musculus pheromone and products corresponding to certain insect pheromones.
Recognizing Hospital Adverse Drug Reactions

Adverse drug reactions (ADRs) are a frequently overlooked complication of drug therapy. The categories of drugs most commonly implicated include anticoagulants, antimicrobials, cardiac agents, CNS agents, diagnostic agents, nonsteroidal antiinflammatory agents, and hormones. In addition to knowing what drug classes most commonly produce ADRs, the clinician should also recognize what drugs are most frequently associated with specific ADRs. Anaphylaxis is one of the most serious, and potentially life-threatening, ADRs. Treatment of an anaphylactic reaction involves correcting the physiologic effects of released chemical mediators and also inhibiting the release of additional mediators. The mainstay of therapy is aqueous epinephrine. Severe reactions may require administration of aminophylline, inotropic agents, antihistamines, corticosteroids, and intravenous fluids. The best treatment for any ADR is prevention. Pharmacists can actively participate in the monitoring of risk factors, especially the number of...
The intracellular organization of bacteriophage tail-like particles in cells of Chromobacterium violaceum following mitomycin C treatment.

The ultrastructure of a strain of Chromobacterium violaceum which produces massive numbers of bacteriophage tail-like particles following treatment with mitomycin C is described and compared to the ultrastructure of normal or untreated cells. Bacteriophage tail-like particles accumulate in bundles in treated cells and never assume the rosette aggregation observed in normal cells. We have designated these particles as defective bacteriophages.
Coherent multiphoton absorption: Dependency on the relative phase of two successive pulses

When a multilevel system excited by a laser pulse absorbs a cascade of photons, a second pulse of same frequency, equal duration but dephased by π takes it back to its initial state. This property can be inferred by studying the laser field system interaction matrix, using the rotating wave approximation.
Ostracodes and Siluro-Devonian Boundary in South-Central Oklahoma: ABSTRACT

Detailed studies of the morphology, ontogeny, variation, and stratigraphic distribution of the ostracodes in the Henryhouse (Silurian) and superjacent Haragan (Devonian) Shales indicate the presence of an unconformity at the Siluro-Devonian boundary in the Arbuckle Mountains of Oklahoma. The ostracodes indicate a late Niagaran (early Ludlovian) age for the Henryhouse Shale and Helderbergian age for the Haragan Shale. The ostracode faunas of both stratigraphic units are large and diversified. The Henryhouse Shale contains 46 species representing 28 genera and 17 families. The Haragan ostracode fauna consists of 53 species, 27 genera, and 16 families. These taxa are distinctive and readily identifiable. Biostratigraphic evidence for the unconformity between End_Page 623------------------------------ the Henryhouse and Haragan follows. (1) At the specific level the two faunas are completely distinct; no species are common to both units. (2) Of the 28 genera in the Henryhouse, 13 are restricted to it. Twelve of the 27 Haragan genera are not present in the Henryhouse. (3) The two faunas are nowhere known to occur together or interfinger with one another. (4) The faunal change is abrupt. There is no evidence for an intermediate (gradational) fauna between the two distinct faunas recognized. The stratigraphic distribution of ostracodes within the Henryhouse and Haragan Shales indicates no definite biostratigraphic zonation within either unit. Each species which is significantly abundant ranges throughout, or almost throughout, the unit in which it occurs. The Henryhouse and Haragan Shales are distinct and discrete stratigraphic units, each having its own ostracode fauna. Detailed sampling of the Henryhouse and Haragan formations has been carried out in all the outcrop areas of the Hunton Group, which consists of four formations, in descending order: Bois d'Arc Limestone, Haragan Shale, Henryhouse Shale, and Chimneyhill Limestone. The ostracode faunas obtained are distinctive and readily identifiable. Eleven ostracode species previously described as Haragan species are now known to have come from, and to be restricted to, the Henryhouse Shale. The ostracode faunas are distinct and discrete. Therefore, the Siluro-Devonian contact in south-central Oklahoma is unconformable. End_of_Article - Last_Page 624------------
A dopaminergic binding site in the high speed supernatant of steer anterior pituitary homogenates.

The high speed supernatant fraction from homogenates of the steer anterior pituitary was shown to contain a high affinity (K = 0.10–0.20 nM), saturable (Bmax = 1.2–3.5 fmol/mg protein), stereoselective binding site for 3H-spiperone (3H-SPIP). The K, (0.10 nM) calculated from the experimentally determined rate constants k1 and k2 was in excellent agreement with that derived from equilibrium measurements. The rank order of potencies of dopaminergic agents to compete for binding was consistent with known dopamine (DA) receptors. Soluble binding sites represented 3% of the total specific binding found in the anterior pituitary, and several lines of evidence suggested they were not due to enzymatic, mechanical or osmotic displacement of membrane receptors. Further studies are necessary to elucidate the possible significance of these soluble binding sites; however, this observation is intriguing since both DA and membrane bound DA receptors enter the cell.
Contrasting patterns of autonomic dysfunction in patients with mitral valve prolapse and panic attacks

Both mitral valve prolapse (MVP) and panic attacks have been reported to be associated with autonomic dysfunction, but previous studies have been limited by the lack of clear separation between patients with MVP and those with panic attacks and the use of noncomparable control subjects. Accordingly, heart rate and blood pressure responses to deep breathing, five minutes' quiet standing, and the Valsalva maneuver were studied in age- and cardiac symptom-matched groups of 33 control subjects, 66 patients with MVP, 20 patients with panic attacks, and 17 patients with both MVP and panic attacks. Compared with control subjects, patients with MVP exhibited more syncope (13 of 66, or 20 percent, versus none of 33, or 0 percent; p less than 0.01), more orthostatic hypotension during quiet standing (11 of 66, or 17 percent, versus one of 33, or 3 percent; p less than 0.01), loss of the normal decrease with age in vagally-mediated heart rate variability during deep breathing (r = 0.13, p = NS versus r = -0.44, p = 0.01), and lower 24-hour epinephrine excretion (6.1 +/- 0.7 versus 11.0 +/- 2.7 micrograms; p less than 0.01). In contrast, patients with panic attacks had greater increases than control subjects or patients with MVP without panic attacks in heart rate, mean blood pressure, and the product of heart rate and mean blood pressure during each minute of quiet standing and during the early strain phase of the Valsalva maneuver. These findings indicate that autonomic dysfunction occurs both in patients with MVP and in those with panic attacks in comparison with symptomatic control subjects, but that the patterns of abnormality differ. Patients with MVP exhibit decreased effectiveness of responses to orthostatic stress, reduced epinephrine excretion, and abnormal vagal tone, whereas patients with panic attacks have heightened cardiovascular responses to postural and positive intrathoracic pressure stresses.
(In,Ga)P buffer layers for ZnSe-based visible emitters

Abstract The growth of ZnSe on pseudomorphic and partially relaxed (In,Ga)P epitaxial buffer layers has been investigated. The (In,Ga)P and ZnSe layers were grown in separate gas source molecular beam epitaxy systems using elemental sources for the cation species and cracked PH 3 and H 2 Se for the anion species. Surface morphology studies using scanning electron microscopy showed that the ZnSe layers were featureless at a magnification of 1.2x10 4 . Four crystal (400) X-ray rocking curves indicated that the ZnSe full width at half maximum (FWHM) was 130″, while the pseudomorphic (In,Ga)P buffer layer FWHM was 18″. The (511) reflections of X-ray rocking curves were used to measure the residual strain as well as the composition in the (In,Ga)P buffer layers. The low temperature photoluminescence spectra from the ZnSe films grown on partially relaxed (In,Ga)P exhibited intensities of the donor-bound and free exciton transitions of nearly equal magnitude, as well as transitions due to extended defects, suggesting highly pure material. The luminescence from the (In,Ga)P buffer layers was also detected.
A new look inside: Wavefront analysis tool for freeform designers

We propose a new wavefront analysis tool for optical designers to evaluate the aberration contribution of each freeform surface inside a complex system, which has great advantages in determining the design form and optimization strategy.
A Neurobiological Theory of Meaning in Perception Part II: Spatial Patterns of Phase in Gamma EEGs from Primary Sensory Cortices Reveal the Dynamics of Mesoscopic Wave Packets

Domains of cooperative neural activity called "wave packets" have been discovered in the visual, auditory, and somatomotor cortices of rabbits that were trained to discriminate conditioned stimuli in these modalities. Each domain forms by a first order state transition, which strongly resembles a phase transition from vapor to liquid. In this view, raw sense data injected into cortex by sensory axons drive cortical action potentials in swarms like water molecules in steam. The increased activity destabilizes the cortex. Within 3 to 7 milliseconds of transition onset, the activity binds together into a state resembling a scintillating rain drop, which lasts ~80 to 100 milliseconds, then dissolves. Wave packets form at rates of 2 to 7/second in all sensory areas, overlapping in space and time. Results of sensory information processing are seen in spatial patterns of amplitude modulation (AM) of wave packets with carrier waves in the gamma range (20 to 80 Hz in rabbits). The AM patterns correspond to categories of CSs that the rabbits can discriminate. The patterns are found in electroencephalographic (EEG) potentials generated by dendrites and recorded with high-density electrode arrays. The state transitions by which AM patterns form are manifested in the spatial pattern of phase modulation (PM), which have the radial symmetry of a cone. The apex of a PM cone marks the site of nucleation of an AM pattern. The phase gradient gives a soft boundary condition, where the axonal delay in spread gives sufficient phase dispersion to reach the half-power level. The size of the wave packets (10 to 30 mm in diameter in rabbits) is determined largely by the conduction velocities of intracortical axons through which the neural cooperation is maintained. The findings show that significant cortical activity takes the form of mesoscopic interactions of millions of neurons in broad areas of cortex, which are more clearly detected in graded dendritic potentials than in action potentials. The distinction is analogous to the difference between statistical mechanical and thermodynamic descriptions of particle behavior. Both types of neural activity show spatial and temporal discontinuities but at distinctive scales of microns and msec versus mm and tenths of a second. The aim of measurement here is to establish the wave packet as the information carrier at the mesoscopic level in brain dynamics, comparable to the role of the action potential as the information carrier at the microscopic level in neuron dynamics.
Gene expression profiling of human liver carcinoma (HepG2) cells exposed to the marine toxin okadaic acid

The marine toxin, okadaic acid (OA) is produced by dinoflagellates of the genera Prorocentrum and Dinophysis and is the causative agent of the syndrome known as diarrheic shellfish poisoning. In addition, OA acts as both a tumor promoter, attributed to OA-induced inhibition of protein phosphatases as well as an inducer of apoptosis. To better understand the potentially divergent toxicological profile of OA, the concentration-dependent cytotoxicity and alterations in gene expression on the human liver tumor cell line HepG2 upon OA exposure were determined using RNA microarrays, DNA fragmentation, and cell proliferation assays as well as determinations of cell detachment and cell death in different concentrations of OA. mRNA expression was quantified for approximately 15,000 genes. Cell attachment and proliferation were both negatively correlated with OA concentration. Detached cells displayed necrotic DNA signatures but apoptosis also was broadly observed. Data suggest that OA has a concentration dependent...
Evidence of an oscillating peripheral clock in an equine fibroblast cell line and adipose tissue but not in peripheral blood

The master mammalian pacemaker in the brain controls numerous diverse physiological and behavioral processes throughout the organism. Timing information is continually transmitted from the master clock to peripheral organs to synchronize rhythmic daily oscillations of clock gene transcripts and control local physiology. To investigate the presence of peripheral clocks in the horse, quantitative real-time RT-PCR assays were designed to detect levels of equine clock genes. Expression profiles for Per2, Bmal1 and Cry1 were first determined in a synchronized equine cell line. Subsequently, expression in equine whole blood and adipose tissue was assessed. Robust circadian oscillations of Per2, Bmal1 and Cry1 were observed in vitro. A synchronized molecular clock was also demonstrated in equine adipose tissue although oscillation of Bmal1 was less robust than that of Per2 and Cry1. In contrast to previous studies in humans and rats however, there was no evidence of synchronized clock gene expression in equine peripheral blood. These studies suggest that synchronous control of clock gene oscillation in equine peripheral blood is not as tightly regulated as in other species and may reflect the influence of different evolutionary challenges modifying the function of a peripheral clock.
Short-Term Conceptual Memory for Pictures.

Three converving procedures were used to determine whether pictures presented in a rapid sequence at rates comparable to eye fixations are understood and then quickly forgotten. In two experiments, sequences of 16 color photographs were presented at rates of 113, 167, or 333 msec per picture. In one group, subjects were given an immediate test of recognition memory for the pictures and in other groups they searched for a target picture. Even when the target had only been specified by a title (e.g., a boat) detection of a target was strikingly superior to recognition memory. Detection was slightly but significantly better for pictured than named targets. In a third experiment pictures were presented for 50, 70, 90 or 120 msec preceded and followed by a visual mask; at 120 msec recognition memory was as accurate as detection had been. The results, taken together with those in 1969 of Potter and Levy for slower rates of sequential presentation, suggest that on the average a scene is understood and so becomes immune to ordinary visual masking within about 100 msec but requires about 300 msec of further processing before the memory representation is resistant to conceptual masking from a following picture. Possible functions of a short-term conceptual memory, such as the control of eye fixations, are discussed.
The Effect of Altering the Cation-Anion Content with Calcium and Phosphorus on the Digestion of Dry Matter and Amino Acids and on Energy Utilization

Abstract Chicks, 30 days old, were fed a corn-soybean meal diet containing different concentrations of cation and anion to determine the effect of acid-base balance on the digestion of dry matter and amino acids and on energy utilization. The concentrations of cation and anion were altered by varying the levels of calcium and phosphorus in the diet. Excess cation (cation minus anion) was negatively correlated (P