cssi/SciSciGPT-SciSciNet huggingface dataset:
Optimal Takeoff Trajectories of a Heavily Loaded Helicopter

Optimal control theory has been applied to the STOL takeoff of a heavily loaded helicopter. The object of the analysis was to determine constrained and unconstrained extremal trajectories that maximize the terminal vertical distance for a given fixed horizontal distance. The resulting optimal trajectory consists of an initial acceleration segment followed by a decelerating segment in which most of the terminal altitude is gained. If the problem was constrained to nondecelerating flight, the resulting optimum consisted of a maximum acceleration segment followed by a constant velocity climbout segment. The slightly decreased performance of the constrained optimum was more than offset by its ease of implementation. Nomenclature A — area of rotor disc Ci-s = momentum theory expansion coefficients CPL = power loss eg = helicopter center of gravity / = wetted drag area of HLD helicopter /o = the derivative of the payoff function with respect to time g = acceleration of gravity HLD = heavily loaded hg = vertical distance measured from the ground plane J = payoff function m = mass of the helicopter Pd = power difference in steady level flight R = radius of rotor R/C = rate of climb ST = reference distance T = thrust t = time Vio = induced velocity V = velocity of the helicopter Vm = smallest velocity where equilibrium flight of the helicopter out of ground effect is possible Vr = reference velocity: induced velocity at hover out of ground effect Vsi = static best climb angle speed Vs2, — static best rate of climb speed W = weight xg = horizontal distance measured on the ground plane Z = vertical height of the rotor above the ground plane CLTP = angle of attack of the rotor tip path plane /3 = dy/dt = control variable rj = dV/dt = control variable 7 = flight path angle dvio = effective reduction of induced velocity of the rotor due to ground effect \H = inflow through the rotor plane nondimensionalized by SIR
Human coronary vascular smooth muscle and endothelium-dependent responses after storage at −75 °C☆

Abstract In the present study, we investigated whether an established method of cryostorage at −75 °C in the presence of dimethyl sulfoxide (Me 2 SO) and fetal calf serum (FCS) could preserve the vascular and endothelial responses of isolated human coronary arteries. A total of 123 ring segments (4–5 mm in length) of epicardial coronary arteries were isolated within 1 to 2 h from hearts of four patients receiving a cardiac transplant. Thirty-nine coronary ring segments were studied immediately upon cleaning of surrounding tissues, while 84 similarly cleaned segments were stored at −75 °C for 7 to 10 days prior to in vitro reactivity studies. In the freshly isolated coronary arteries, addition of prostaglandin F 2 α, endothelin (ET-1), or acetylcholine consistently produced a dose-dependent contraction, reaching a maximum contractile force of 9.6 ± 0.7, 4.5 ± 0.5, and 3.1 ± 0.5 g (M ± SEM), respectively, while histamine, thrombin and substance P consistently produced an endothelium-dependent relaxation (EDR) with a maximum of −89 ± 2.8, −85 ± 5.0, and −72 ± 3.5%, respectively. Isoproterenol produced an endothelium-independent relaxation (−82 ± 4.5%). Cryostorage of human coronary arteries at −75 °C without cryoprotectant resulted in a complete loss of the contractile response. In contrast, addition of Me 2 SO and FCS in the cryostorage medium significantly preserved the contractile responses, although they were decreased (1.9 ± 0.3, 1.5 ± 0.3, and 0.6 ± 0.1 g to PGF 2 α, ET-1, and acetylcholine, respectively) when compared to the fresh controls. The maximum EDR to histamine, thrombin, and substance P in the cryostored coronaries were also reduced to −40 ± 5.6, −21 ± 3.3, and −47 ± 4.7%, respectively, and the isoproterenol-induced relaxation was reduced to −62 ± 4.1%. These results suggest that although the cryostorage method described in the present report provided only limited preservation of human coronary arteries, significant vascular smooth muscle and endothelial-dependent functions were retained. Thus, it is possible that further refinement of the present cryostorage methodology may provide better preservation of functionally viable human blood vessels.
Identification of a CCR5-expressing T cell subset that is resistant to R5-tropic HIV infection.

Infection with HIV-1 perturbs homeostasis of human T cell subsets, leading to accelerated immunologic deterioration. While studying changes in CD4+ memory and naive T cells during HIV-1 infection, we found that a subset of CD4+ effector memory T cells that are CCR7−CD45RO−CD45RA+ (referred to as TEMRA cells), was significantly increased in some HIV-infected individuals. This T cell subset displayed a differentiated phenotype and skewed Th1-type cytokine production. Despite expressing high levels of CCR5, TEMRA cells were strikingly resistant to infection with CCR5 (R5)–tropic HIV-1, but remained highly susceptible to CXCR4 (X4)–tropic HIV-1. The resistance of TEMRA cells to R5-tropic viruses was determined to be post-entry of the virus and prior to early viral reverse transcription, suggesting a block at the uncoating stage. Remarkably, in a subset of the HIV-infected individuals, the relatively high proportion of TEMRA cells within effector T cells strongly correlated with higher CD4+ T cell numbers. These data provide compelling evidence for selection of an HIV-1–resistant CD4+ T cell population during the course of HIV-1 infection. Determining the host factors within TEMRA cells that restrict R5-tropic viruses and endow HIV-1–specific CD4+ T cells with this ability may result in novel therapeutic strategies against HIV-1 infection.
HIGHLY NONLINEAR OPTICAL EFFECTS IN LIQUID CRYSTALS

CW laser fields are strong enough to induce a large refractive index change in a liquid crystal. Optical-field-induced structural transition can occur. The large optical nonlinearity can lead to some unusual highly nonlinear optical phenomena.
Breaking SIMD shackles with an exposed flexible microarchitecture and the access execute PDG

Modern microprocessors exploit data level parallelism through in-core data-parallel accelerators in the form of short vector ISA extensions such as SSE/AVX and NEON. Although these ISA extensions have existed for decades, compilers do not generate good quality, high-performance vectorized code without significant programmer intervention and manual optimization. The fundamental problem is that the architecture is too rigid, which overly complicates the compiler's role and simultaneously restricts the types of codes that the compiler can profitably map to these data-parallel accelerators. We take a fundamentally new approach that first makes the architecture more flexible and exposes this flexibility to the compiler. Counter-intuitively, increasing the complexity of the accelerator's interface to the compiler enables a more robust and efficient system that supports many types of codes. This system also enables the performance of auto-acceleration to be comparable to that of manually-optimized implementations.To address the challenges of compiling for flexible accelerators, we propose a variant of Program Dependence Graph called the Access Execute Program Dependence Graph to capture spatio-temporal aspects of memory accesses and computations. We implement a compiler that uses this representation and evaluate it by considering both a suite of kernels developed and tuned for SSE, and "challenge" data-parallel applications, the Parboil benchmarks. We show that our compiler, which targets the DySER accelerator, provides high-quality code for the kernels and full applications, commonly reaching within 30% of manually-optimized and out-performs compiler-produced SSE code by 1.8 times.
Clinical utility of routine barium esophagram after laparoscopic anterior esophageal myotomy for achalasia.

Background This study aimed to evaluate the clinical utility of routine barium esophagram after laparoscopic anterior esophageal myotomy for achalasia.
Transatlantic Encounters: Europeans and Andeans in the Sixteenth Century

Transatlantic Encounters: Europeans and Andeans in the Sixteenth Century. Kenneth J. Andrien and Rolena Adorno. Berkeley: University of California Press, 1991. viii + 295. $45.00 (cloth). ISBN 0–520–07228–6.
Determination of shipboard electric short-circuit currents

Several methods of calculating short-circuit currents are compared in an effort to arrive at a relatively simple and satisfactory longhand method. Several shipboard tests are reviewed and their results used to evaluate the recommended system.
P nucleotides, hairpin DNA and V(D)J joining: making the connection

The fine-structures of V(D)J joining products present a cache of information about the recombination process. Testable hypotheses with predictive value are beginning to provide a surprisingly detailed picture of the joining operation. Here, one feature of V(D)J junctions, the appearance of short palindromic inserts, is discussed, and experimental evidence in support of a joining model involving a hairpin-terminated DNA intermediate will be summarized.
Expert system for evaluation of reproductive performance and management.

Abstract A microcomputer expert system for dairy herd reproductive management was developed using an expert system shell and Turbo Pascal. The expert system initially examines the broad areas of days open, days to first breeding, detection of estrus, and conception rate to determine whether a problem exists. Interpretations ranging from “excellent” to “severe” were established for each trait. The system then selects an area for evaluation that has the largest negative influence on days open. Once an area has been selected for further evaluation, the expert system utilizes information from the user and DHI reports developed by the Dairy Records Processing Center in Raleigh, NC. These reports identify problems with conception categorized by production, parity, service number, days in milk, breed, and service sire. In addition, questions are presented by the expert system to isolate problems of accuracy of data, use of natural service, semen handling, AI technique, detection of estrus, signs of estrus, and other management areas. Recommendations and suggestions are given. Ten commercial herds having a conception rate less than 40% were evaluated by the expert system and by an extension reproduction specialist who supplied information for the system. Of 100 areas investigated, the expert system and extension specialist identified 47 as potential problem areas, agreeing on 85% of them. Most discrepancies resulted from the specialist applying a less restrictive standard when values were close to a preselected threshold.
Perception of neighborhoods by city and suburban residents

A number of neighborhood studies have supported the view that urban areas are a mosaic of local communities or neighborhoods with clear boundaries and a high degree of identity. However, many of these studies are based on highly identifiable innercity natural areas in large metropolitan centers; thus, the generalizability of these findings is limited. Two studies broadened the investigation of these issues by looking at neighborhood perceptions of residents living in relatively undifferentiated innercity, outercity, and suburban areas of a middle-sized metropolitan area. In both studies, residents were asked to draw and describe their neighborhood. The first study (N=72) indicated that the content of neighborhood images differed by area of the city: city residents ascribed the same number of positive characteristics, but more negative characteristics to their neighborhood than did suburban residents. Moreover, suburban residents in both studies drew neighborhoods that were substantially larger than the innercity neighborhoods. The second study, conducted with 24 immediate neighbors from the inner city and suburb, indicated that in both areas there was a high degree of agreement among neighbors on the neighborhood limits, but little consensus on a neighborhood name. These results support and extend the local community model of neighborhoods: From city to suburb the imagability of neighborhood does not differ; it is both high and consensual. But the content of the image does change; suburban neighborhoods are seen as larger and less negative.
Morphological stability of cylindrical ice crystals

Abstract Single crystal ice cylinders have been grown into undercooled water. The growth rates of perturbations in the circular shape of the cylinder are in agreement with the predictions of a Mullins-Sekerka stability analysis. The growth rates of perturbations along the axis of the cylinder yield a value of 0.022 J/m 2 (22 erg/cm 2 ) for the ice-water surface tension of planes parallel to the c -axis.
Molecular Simulation Uncovers the Conformational Space of the λ Cro Dimer in Solution

The significant variation among solved structures of the λ Cro dimer suggests its flexibility. However, contacts in the crystal lattice could have stabilized a conformation which is unrepresentative of its dominant solution form. Here we report on the conformational space of the Cro dimer in solution using replica exchange molecular dynamics in explicit solvent. The simulated ensemble shows remarkable correlation with available x-ray structures. Network analysis and a free energy surface reveal the predominance of closed and semi-open dimers, with a modest barrier separating these two states. The fully open conformation lies higher in free energy, indicating that it requires stabilization by DNA or crystal contacts. Most NMR models are found to be unstable conformations in solution. Intersubunit salt bridging between Arg4 and Glu53 during simulation stabilizes closed conformations. Because a semi-open state is among the low-energy conformations sampled in simulation, we propose that Cro-DNA binding may not entail a large conformational change relative to the dominant dimer forms in solution.
Metastable surface structures of the bimetallic Sn/Pt(1 0 0) system

Abstract An ordered Sn overlayer on Pt(1 0 0) and several metastable Sn/Pt(1 0 0) surface alloys were studied using scanning tunneling microscopy (STM), low energy electron diffraction (LEED), and Auger electron spectroscopy (AES). These surfaces were studied previously using alkali-ion scattering spectroscopy (ALISS), LEED, and CO chemisorption, in order to determine conditions for alloy formation [Surf. Sci. 330 (1995) 193]. In those earlier studies, structural transitions with increasing annealing temperatures from a c(2 × 2)-Sn overlayer to a c(2 × 2)-Sn/Pt(1 0 0) surface alloy and finally to a (3√2×√2)R45° alloy structure were observed. Here STM is used to determine surface morphologies and atomic scale structures of these alloys. Sn (0.67 ML) deposited on the reconstructed Pt(1 0 0)-hex surface and annealed to 550 K formed a c(2 × 2)-Sn overlayer with compact, monolayer-high islands with step edges oriented along the [1 0 0] and [0 1 0] azimuths. Annealing the sample to 750 K initiated alloying and a c(2 × 2) surface alloy formed locally. However, the c(2 × 2) alloy structure does not appear to be stable even at this early stage of alloying and narrow channels along the 〈1 0 0〉 crystallographic directions form. For higher annealing temperatures, these channels evolve to form a two-domain structure with almost equidistant channels along the [1 0 0] and [0 1 0] directions, respectively. A dominant channel separation of 3√2 times the surface-lattice constant of Pt(1 0 0) is observed. This channel separation gives rise to a streaky (3√2×√2)R45° LEED pattern. The channels are characterized by three missing atomic rows. Between these channels are narrow terraces that are predominantly three-atomic-rows wide. The step edges of these terraces are Pt-terminated, while Sn is alloyed in the center of these terraces. A local p(2 × 2) ordering of alloyed Sn is often observed for wider terraces. Annealing to 1000 K results in “fragmentation” of the narrow terraces to form small, often square, islands with side-lengths as small as √2 times the surface-lattice constant of Pt(1 0 0). The structural characterization of these Sn/Pt(1 0 0) surfaces is used to interpret previous chemical adsorption studies.
Commercial Profitability of Offshore Sand and Gravel Mining in Southern California: An Analysis of New Entries

Sand and gravel are primary resources used in many phases of construction and to maintain southern California's valuable beaches and harbors. Deposits of saleable-grade material under present political and economic conditions are becoming depleted. Although many land-based deposits are lost to competing land uses and mining of such deposits is generally opposed by urban communities, offshore mining of sand and gravel for use as construction aggregate is below the current rate of market interest (10%). The reduced profitability of offshore mining is chiefly due to high initial capital outlay and relatively high operating costs. Investment in land-based deposits may be profitable under specified conditions.
Stigmata of Turner's syndrome in woman with regular menstrual rhythm.

We have recently been given the opportunity to study the following interesting patient who, although she presented several stigmata of Turner's syndrome including two of the most important ones (webbing of the neck and cubitus valgus), nevertheless menstruated regularly: O.S., a 27-year-old white female registered nurse consulted one of us (R.O.S.) to ascertain whether her congenitally webbed neck could be corrected surgically. There were no other complaints, except with regard to her menstrual status. Her menarche had occurred at 14 years of age, following which the menses were regular at 28-day to 30-day intervals with a full 5-day flow until the age of 23, when they become increasingly scant. They remained regular but the amount of vaginal bleeding decreased progressively until at the time she was seen by us there was only a 2-day flow followed by one or two days of spotting. In addition, the patient noted a moderate decrease in the size of her breasts. She stated that pubic and axillary hair had alway...
The Solution of the ~-Neumann Problem in a Strictly Pseudoconvex Siegel Domain

In this paper, we solve the O-Neumann problem on (0,q) forms, q > 0, in the strictly pseudoconvex Siegel domain. The metric we use is invariant under the action of the Heisenberg group on the domain. We give a formula for a kernel of the Neumann operator, the fundamental solution of the problem, in (1.6) and Theorem 4.2, and we prove uniqueness of the Neumann operator. As far as we know, this is the first example of an explicit solution of the ~-Neumann problem. Greiner and Stein [GS] constructed a parametrix for the problem on (0, 1) forms in bounded strictly pseudoconvex domains. Phong [P] has announced an explicit construction of a parametric on (03) forms in the Siegel domain in C "+ 1, n > 1. Harvey and Polking [HP] have since constructed a Neumann kernel for the ~-Neumann problem on (p, q) forms on the ball. We obtain the kernel of the Neumann operator by integrating the fundamental solution of the corresponding heat equation ([S1], [$2]) with respect to time. To carry out the integration, we require estimates on the fundamental solution for large time. We did not need such estimates in [$1] and [$2]. Also, to prove that the resulting kernel is locally integrable, we require more precise estimates for small time. In Sect. 1, after some preliminaries, we state our main theorem. We then summarize the results of [S1 ] and [$2]. We solve the corresponding elliptic problem on C" + 1 in Sect. 2. In Sect. 3 we study the operator which corrects the boundary values of the solution we obtained in Sect. 2. We solve the O-Neumann problem in Sect. 4. Most of the work for this paper was done while I was a member of the Institute for Advanced Study. I wish to thank the Institute for its hospitality.
Promethium Oxide Structure

FROM the results of radiochemical distribution experiments, M. Bruno and U. Croatto1 concluded that over a large range of temperatures promethium sesquioxide has a fluorite-type structure. We have examined a sample of promethium sesquioxide powder by means of X-ray diffraction and have found reflexions which are consistent with a fluorite-type structure. The promethium-147 oxide was about 99 per cent pure with the remaining impurity being the daughter, samarium-147. This oxide was prepared by heating promethium oxalate in air for 3 h at 750° C. About 15 mg of the oxide were placed in a lead sample holder, one end of which was closed by a film of ‘Cellophane’ tape through which the X-ray diffraction pattern was obtained by the use of a General Electric XRD-5 diffractometer.
Automated docking of isomaltose analogues in the glucoamylase active site

Abstract Low-energy conformers of analogues of the disaccharide isomaltose were determined with MM3(92) and were then flexibly docked into the glucoamylase active site using AutoDock 2.1. This procedure has produced bound complexes of saccharides with glucoamylase comparable to those obtained by protein crystallography. Conformational energy surfaces of three methyl α-isomaltosides, two with a second methyl group at C-6 B , were determined to characterize the steric limitations introduced by that group. Their most probable conformers were used as initial structures for docking. Seven sets of monodeoxy methyl α-isomaltoside structures were also generated based on the methyl α-isomaltoside conformational map and were docked to probe the contribution of individual hydroxyl groups to binding. The optimized docking modes are similar for most analogues, and energies of intermolecular interaction per extended atom agree with the assignment of key hydroxyl groups made from kinetic studies. This new approach to study saccharide-protein interactions complements the results of protein crystallography, allowing a better understanding of the interaction of glucoamylase with its substrates.
Immunological identification of human platelet mitochondrial DNA topoisomerase I.

A nuclear human blood platelets have been used to study mitochondrial topoisomerase activity in the absence of nuclear contamination. Previous work utilizing this novel system demonstrated that platelet mitochondria contain type-I topoisomerase (Kosovsky, M.J. and Soslau, G. (1991) Biochim. Biophys. Acta 1078, 56-62). The present work has demonstrated that mitochondrial topoisomerase activity was inhibited by the specific topoisomerase-I inhibitor, topotecan, yet was not affected by a specific topoisomerase-II inhibitor, VM-26. These results confirm that platelet mitochondria contain topoisomerase I, yet do not contain a detectable level of topoisomerase-II activity. It has been demonstrated for the first time that antibodies directed against nuclear topo I cross-react with mitochondria topo I. Furthermore, immunoblot analysis of platelet mitochondrial proteins, in conjunction with renaturation studies, has led to the identification of a catalytically active 60-kDa form of mitochondrial topoisomerase I.
Examining Whether Dental Therapists Constitute a Disruptive Innovation in US Dentistry

Dental therapists-midlevel dental providers who are roughly analogous to nurse practitioners in medicine-might constitute a disruptive innovation within US dentistry. Proponents tend to claim that dental therapists will provide more equitable access to dental care; opponents tend to view them from a perspective that focuses on retaining the current attributes of the dental profession. Therapists display traits similar to those of disruptive innovations: their attributes are different from dentists', they may not initially be valued by current dental patients, they may appeal to current dental underutilizers, and they may transform the dental delivery system. Whether dental therapists constitute a disruptive innovation will only be determined retrospectively.
COMPARISON OF THE RORSCHACH COMPREHENSIVE SYSTEM'S ISOLATION INDEX AND MMPI SOCIAL INTROVERSION SCORE

Summary.-An attempt was made to test the hypothesis that Exner's 1986 Isolation Index and the Social Introversion scale of the Minnesota Multiphasic Personality Inventory tap closely related areas of personality functioning. 50 criminal defendants referred for psychiatric evaluation were routinely administered the Rorschach and MMPI as a standard part of the assessment process. Although analysis showed no significant relationship between Isolation Index and Social Introversion scores, the results do not necessarily invalidate the Isolation Index, but do indicare thar it taps traits different from those measured by the Social Introversion scale. Replication on a ddferent population is recommended. Exner (1986) discusses how the Isolation Index evolved from a series of computer searches investigating the relationship between a variety of content categories and subject characteristics. These investigations provided evidence that a combination of five content categories (Botany, Clouds, Geography, Landscape, and Nature) was related to an individual's degree of social isolation. The Isolation Index (Isolate: R) compares the sum of these five contents (Isolate) to the total number of responses (R). Exner suggests that if the former value is greater than one-fourth the latter "a marked tendency toward social isolation exists." He does warn that the ratio should be used cautiously since supportive data are limited to two unpublished
Chemical mediation of invertebrate defensive behaviors and the ability to distinguish between foraging and inactive predators

When the predatory sea star Pycnopodia helianthoides was placed upstream, the sea urchin Strongylocentrotus purpuratus responded defensively by extending and opening its globiferous pedicellariae. No pedicellaria response was given in control seawater or when the sea star was downstream. The snail Tegula funebralis responded by moving up vertical surfaces when Pycnopodia helianthoides or when Pisaster ochraceus were placed upstream. When these sea stars were introduced downstream, the snail's response was not significantly different from that in control seawater. Water collected from an aquarium containing a single sea star was sufficient to trigger the response of S. purpuratus and T. funebralis; the physical presence of the sea star was not essential. This indicated that a chemical stimulus was involved, and the lack of responses when sea stars were downstream argued strongly against the possible additional involvement of visual or vibrational stimuli. S. purpuratus gave stronger pedicellaria responses to water flowing over an active Pycnopodia helianthoides than to water flowing over the same sea star when it was inactive. The significance of the ability to distinguish between actively foraging and inactive predators is discussed, and a mechanism is proposed to explain differences in the amount of stimulatory chemicals released by active and inactive sea stars.
Propagation of Surface Acoustic Pulses Generated by a Femtosecond Laser in Thin Films on Solid Substrates

The technique of phase velocity dispersion measurements of surface acoustic waves in a thin film-substrate system was demonstrated. The excitation of surface acoustic waves (SAWs) was quite efficient with femtosecond laser pulses, and the damage of the surface was minimized. The measurements were performed with films of Al deposited on silicon wafers. The errors in the determination of the phase velocity and absorption were analyzed. The temperature changes in the propagation velocity on bare Si wafers were also measured. The data obtained permitted estimation of the accuracy of the temperature determination from measurements with SAW pulses.
Aggression Replacement Training: A Multimodal Intervention for Aggressive Adolescents

SUMMARY This article provides an overview of Aggression Replacement Training (ART), an empirically validated and theoretically grounded multimodal intervention designed to prevent and reduce aggression in adolescents. ART consists of three components: (1) skills streaming, designed to teach a broad range of social skills; (2) anger control training, a method for empowering youth to modify their own anger responsiveness; and (3) moral reasoning education, training to motivate youth to use skills acquired through the other two training components. Implementation issues are presented. Strategies to successfully transfer and maintain acquired skills, as well as enhance trainee motivation, are outlined. Efficacy studies suggest that ART is an effective program for aggressive adolescents in a wide range of treatment settings.
Prostaglandin-induced neurodegeneration is associated with increased levels of oxidative markers and reduced by a mixture of antioxidants.

Prostaglandin E2 (PGE2), one product of inflammatory reactions, and PGA1, which is formed during PGE2 extraction, induce degeneration in adenosine 3′,5′-cyclic monophosphate (cAMP)-induced differentiated neuroblastoma (NB) cells in culture. The mechanisms of action of PGE2 on neurodegeneration are not well understood. To investigate this, we have utilized PGA1, which mimics the effect of PGE2 and is very stable in solution. We have assayed selected markers of oxidative stress such as heme oxygenase-1 (HO-1), catalase, glutathione peroxidase (GPx1), mitochondrial superoxide dismutase (Mn-SOD-2) and cytosolic superoxide dismutase (Cu/Zn-SOD-1). The results showed that the treatment of differentiated NB cells with PGA1 for a period of 48 hr increased the expression of HO-1 and catalase, decreased the expression of GPx1 and Mn-SOD-2, and did not change the expression of Cu/Zn-SOD-1 as measured by gene array and confirmed by real-time PCR. The protein levels of HO-1 and GPx1 increased; however, the protein level of Mn-SOD-2 decreased and the levels of catalase and Cu/Zn-SOD-1 did not change as determined by Western blot. The increases in the levels of HO-1 and GPx1 reflected an adaptive response to increased oxidative stress, whereas decrease in the level of Mn-SOD-2 may make cells more sensitive to oxidative damage. These data suggest that one of the mechanisms of action of PGA1 on neurodegeneration may involve increased oxidative stress. This was supported further by the fact that a mixture of antioxidants (α-tocopherol, vitamin C, selenomethionine, and reduced glutathione), but not the individual antioxidants, reduced the level of PGA1-induced degeneration in differentiated NB cells. The addition of a single antioxidant at two or four times the concentration used in the mixture was toxic. © 2005 Wiley-Liss, Inc.
Intracytoplasmic sperm injection experiments using the mouse as a model

Due to the existence of ample background information on its reproduction, embryology and genetics, the mouse is potentially an excellent animal model for intracytoplasmic sperm injection (ICSI). Normal fertile mouse offspring have been obtained by ICSI using not only mature (epididymal) and immature (testicular) spermatozoa, but also round spermatids and secondary spermatocytes. This suggests that genomic imprinting of male germ cells is complete before spermiogenesis. Mature mouse spermatozoa carry one or more factors that activate oocytes. This sperm-borne oocyte-activating factor is present in testicular spermatozoa, but not in round spermatids. Thus, at least in the mouse, it seems to appear (or become active) during spermiogenesis. Part of the factor seems to be associated with the perinuclear materials because, when freed from plasma and acrosomal membranes as well as all acrosome components, spermatozoa remain fully capable of activating oocytes by ICSI. Spermatozoa with grossly misshapen heads (e.g. those from the BALB/c mouse) are unable to fertilize oocytes under ordinary in-vivo and in-vitro conditions. However, by ICSI they can fertilize the oocytes, and the zygotes develop into fertile offspring. Inherently poorly motile spermatozoa (of male mice carrying two t haplotypes) are unable to fertilize, but through ICSI they can participate in normal fertilization and embryonic development. Examination of human sperm chromosomes after sperm injection into mouse oocytes revealed that spermatozoa with abnormal head morphology have a significantly higher incidence of chromosome abnormality than those with normal heads, yet the majority of the abnormal spermatozoa have normal chromosomal constitutions. These findings suggest that spermatozoa with aberrant morphology and/or motility are not necessarily genomically abnormal.
Bistatic radar measurements of the surface of Mars with Mariner 1969

The detection of echoes produced by oblique reflection of the RF (2300 MHz) spacecraft carrier from the Martian surface as Mariner 6 and 7 flew behind Mars in 1969, is described. Changes in echo center frequency and bandwidth are utilized to study the radius and roughness of the surface along a quasi-specular radar track that led from an optically dark and densely cratered region of Meridiani Sinus over into a smoother and brighter looking area of Thymiamata. A 3 to 1 decrease in surface roughness of large size compared to the wavelength (13 cm) was observed as the reflecting zone moved across the boundary between these two regions. The average radius obtained along the track was 3393 plus or minus 3 km. Due to large angles of incidence (86 to 90 deg), and surface shadowing, the data are not suitable for mapping the reflection coefficient of the surface material.
Tumor Necrosis Factor-α Internalization and Degradation by Isolated Hepatocytes of Rats Exposed to Ethanol

Internalization and degradation of human recombinant [125I]TNF-alpha was studied in hepatocytes isolated from rats exposed to ethanol (EtOH) either acutely (i.p. injection, 2.2 g kg(-1) b.wt.) or chronically (14-16 weeks of EtOH feeding in liquid diet). Both acute and chronic EtOH exposure diminished cytokine binding to the cell-surface receptors. In the acute group, EtOH increased internalization of the cytokine, accelerated its disappearance from the cell surface, and markedly reduced its conversion into acid-soluble 125I-containing compounds. In the chronic group, EtOH did not markedly affect these parameters. Internalization and degradation of the cytokine in the chronic group was much lower than in the acute group. It is concluded that EtOH interferes not only with the cytokine binding to the cell-surface receptors, as demonstrated in previous studies, but also with postbinding events, such as internalization and intracellular degradation of TNF-alpha. Possible mechanisms of action of EtOH are discussed.
A Closer Look at Effect Sizes and Their Relevance to Health Education

Abstract A number of academic disciplines are engaged in scholarly discussions regarding statistical practice reform, particularly the use of effect sizes. Health education must stimulate a similar conversation by adopting strategies for generating, reporting, and interpreting effect size estimates for various statistical analyses within journal articles. The purpose of this article is to demonstrate the practical applications of effect size reporting and interpretation in health education research. Congruent with previous recommendations in the American Journal of Health Education, this article will provide examples and techniques used for effect size reporting that educate the researcher and practitioner, thus improving the scholarship of health education publications. Effect size reporting should become the rule for health education and concerted efforts should be made to equip researchers and practitioners with the proficiency to perform this task effectively. Such skill building will increase the sch...
Infrared studies of star formation.

The lifetime of a massive star before it begins to deplete its nuclear fuel is less than 5 million years (1). In contrast, the age of the galaxy is more than 10 billion years (2); nevertheless, many massive and short-lived stars have been identified by observations at optical wavelengths. These massive stars must have formed very recently relative to the age of the galaxy, and therefore star formation must be occurring in the galaxy at the present time.
Shiftwork and Industrial Injuries at A Chemical Plant in Southeast Texas

–A historical retrospective study of 242 shiftworker (SW) and 224 non-SW (NSW) injuries at a chemical manufacturing plant in southeast Texas (U.S.A.) was performed. Data were collected on injuries that occurred between 1 January 1982 and 31 December 1985. The SW schedule comprised an 8-hr, 7-day backward rotation program while the dayworker schedule consisted of a typical U.S.A. 40-hr work week. Injury records were matched against payroll/attendance records to substantiate the probability of isolating possible effects of the shiftwork rotation schedule on the rates, distribution and severity of injuries. Injuries in the SW sample were compared to those in the non-SW sample. The work responsibilities of dayworkers were not exactly the same as those of shiftworkers. However, the job responsibilities for males and females within the dayworker and shiftworker groups were equivalent. Overall injury incidence rates were not significantly different between SWs and non-SWs, although female SWs had significantly h...
Algorithms to control coal segregation under non-stationary conditions: Part II: Time series based methods

Abstract In this paper, procedures involving the use of time series models are developed for coal segregation control. In contrast to the methods of Part I of this paper, time series models directly accommodate the auto-correlated nature of the coal quality levels when estimating parameters to characterize the process. Moreover, they also provide forecasting capability that is useful in segregation control. Special attention is given in the paper to development of viable parameter updating strategies in order to deal with non-stationary applications. Performance of the time series methods is evaluated, and it compares favorably to the methods developed in Part I. Although more complicated to implement than the Part I methods, time series methods have the potential to be extended to applications where quality targets are to be maintained over small batches of coal (homogeneity control), whereas the other methods only apply to large batch quality targeting.
Phosphorylated and nonphosphorylated prolactin isoforms

Specific posttranslational modifications o f monomer PRL produce a number of hormone variants. This review describes the current state of knowledge for the nonphosphorylated and phosphorylated 24-kD monomer forms. Of particular interest and significance for our future understanding of PRL endocrinology are the studies showing their differential release in response to different physiologic signals and their different activities in target tissues. In at least two target tissues, the monophosphorylated variant seems to act as an antagonist to the unmodified hormone.
Metabolism of Thrombospondin 2 BINDING AND DEGRADATION BY 3T3 CELLS AND GLYCOSAMINOGLYCAN-VARIANT CHINESE HAMSTER OVARY CELLS

Thrombospondin 1 (TSP1) and thrombospondin 2 (TSP2) are members of the thrombospondin family that have a similar structural organization but somewhat different functional activities. Iodinated recombinant mouse TSP2 bound to NIH 3T3 cells and was internalized and degraded through a chloroquine-inhibitable pathway. TSP2 degradation was saturable, specific, and similar to the kinetics of degradation of TSP1. Human platelet TSP1, recombinant mouse TSP1, and recombinant mouse TSP2 cross-competed with one another for degradation by 3T3 cells. Degradation of TSP2 was less sensitive to inhibition by heparin than degradation of TSP1. This is in agreement with differences in heparin-binding affinity of the two TSPs. Degradation of TSP2 was slower in cultures of Chinese hamster ovary (CHO) cells lacking heparan sulfate proteoglycans than in wild type CHO cells or in cultures of 3T3 cells treated with heparitinase than in untreated 3T3 cells. Degradation of TSP2 was inhibited by antibodies against the low density lipoprotein receptor-related protein (LRP) or by the 39-kDa receptor-associated protein, a known antagonist of LRP. This study indicates that TSP2 and TSP1 are metabolized by a common internalization and degradation pathway involving heparan sulfate proteoglycan and LRP. Competition for this pathway is a possible mechanism whereby cells can control the levels and ratio of TSP1 and TSP2 in the extracellular milieu.
Dynamic and LHHW Kinetic Analysis of Heterogeneous Catalytic Hydroformylation

Abstract Heterogeneous ethylene hydroformylation on a 4 wt% Rh/SiO2 catalyst was studied using a steady-state pulse transient method coupled with in situ infrared spectroscopy. Four independent quantities, including the rates of propionaldehyde and ethane formation and the surface coverages of adsorbed CO and adsorbed acyl species, were measured at steady state as a function of the partial pressures of the reactants. The coverage of intermediates during ethylene hydroformylation was determined from the dynamic response of (C2H513CHO to a 13CO pulse input. The coverage of adsorbed CO was measured by in situ IR spectroscopy. The rate laws for C2H5CHO and C2H6 formation and the isotherm equations for adsorbed C2H5CO and adsorbed CO were derived using the Langmuir-Hinshelwood-Hougen-Watson (LHHW) approach from a proposed mechanism with the hydrogenation of adsorbed C2H5CO as the rate-determining step for propionaldehyde formation and the hydrogenation of adsorbed C2H5 as the rate-determining step for ethane formation. The high degree of fitting of rate and coverage data to the derived rate law and isotherm equations suggests that the LHHW model describes the surface reaction with high accuracy. Although the assumptions for the Langmuir isotherm do not account for the interactions between adsorbates, the LHHW equations and the proposed mechanism satisfactorily describe the kinetics, reaction pathways, and rate-limiting steps for the formation of ethane and propionaldehyde. This study demonstrates that the measurement of coverage of adsorbates by isotopic tracer pulsing and in situ infrared spectroscopy provides direct experimental evidence to confirm a postulated mechanism and rate law.
Angina de Vincent y angina de Ludwig: dos infecciones orales peligrosas

EN UN PRIMER MOMENTO, cuando usted lee el diagnostico de angina de Vincent o angina de Ludwig, puede pensar que se trata de un dolor toracico o sintomas que sugieren una isquemia de miocardio. Realmente la angina pectoris es el tipo de angina mas popular, pero angina, una palabra latina para el dolor agudo y as xiante, tambien describe varios trastornos de la cavidad oral causados por infecciones bacterianas. Aunque muy similares, la angina de Vincent y la de Ludwig di eren en la localizacion, en las manifestaciones clinicas y en su control. Este articulo revisa las situaciones y las implicaciones para los cuidados de enfermeria.
Perifusion of saurian pancreatic islets and biphasic insulin release following glucose stimulation.

1. 1. The effect of low and high concentrations of glucose on insulin release from pancreatic islets of Anolis carolinensis in an in vitro perifusion system has been determined. 2. 2. A biphasic pattern of insulin secretion is obtained in the presence of a high concentration of glucose. 3. 3. The temporal relationships of the biphasic response following glucose stimulation are similar to those observed in vivo and in vitro with mammals.
Orientations, purposes and reflection: a framework for understanding action research

Abstract Interest in action research has grown exponentially during the last twenty years. Each year, more and more educators are becoming involved in action research through a variety of activities, such as credit-bearing courses, school restructuring efforts, and professional development. Because of the different roles and perspectives of participants in these activities (teachers, teacher educators, school administrators, parents), multiple models of action research have evolved. In this paper we present a framework for the comparison and evaluation of action research that transcends differences among existing models. Our framework or schema has as its dimensions theoretical orientation [Grundy, S. (1987). Curriculum: products or praxis. Falmer: New York] purposes [Noffke, S. (1997). Review of Research in Education , 22 , 305–343] and types of reflection [Rearick, M. (1998). ERIC Document Reproduction Service No. ED 412 229]. We tested our framework by using it to analyze several recent books on action research written by teacher educators. When applied to those current studies, our framework served to clarify the different approaches employed: what orientations were served (technical, practical, emancipatory), what purposes of action research were emphasized (personal, professional, or political), and what types of reflective processes were used (autobiographical, collaborative, or communal). The schema that we offer here can help future action researchers find the model most suited to their objectives and interests.
EXPERIMENTAL INVESTIGATIONS ON THE LIGHT SCATTERING OF COLLOIDAL SPHERES. III. THE SPECIFIC SCATTERING AT 90 DEG.

Abstract An experimental arrangement for precise light-scattering measurements from colloidal solutions at an angle of 90° with respect to the primary beam is described. The results obtained from sixteen polystyrene and polyvinyltoluene latices with particle diameters ranging from 46 to 824 mμ provide an additional verification of the Mie theory of light scattering. The effect of multiple scattering and of the solid angle are studied and methods for excluding their interference with particle size determinations are described which should be useful also for molecular weight determinations in polymer solutions. The problem of the instrument constant is analyzed, and a principle is pointed out whereby quasi-absolute lateral scattering data can be obtained by suitable internal compensation within a properly constructed apparatus. The advantages and disadvantages of lateral measurements as compared to turbidity measurements are pointed out.
Benefit of "Push-pull" Locomotion for Planetary Rover Mobility

As NASAs exploration missions on planetary terrains become more aggressive, a focus on alternative modes of locomotion for rovers is necessary. In addition to climbing steep slopes, the terrain in these extreme environments is often unknown and can be extremely hard to traverse, increasing the likelihood of a vehicle or robot becoming damaged or immobilized. The conventional driving mode in which all wheels are either driven or free-rolling is very efficient on flat hard ground, but does not always provide enough traction to propel the vehicle through soft or steep terrain. This paper presents an alternative mode of travel and investigates the fundamental differences between these locomotion modes. The methods of push-pull locomotion discussed can be used with articulated wheeled vehicles and are identified as walking or inchinginch-worming. In both cases, the braked non-rolling wheels provide increased thrust. An in-depth study of how soil reacts under a rolling wheel vs. a braked wheel was performed by visually observing the motion of particles beneath the surface. This novel technique consists of driving or dragging a wheel in a soil bin against a transparent wall while high resolution, high-rate photographs are taken. Optical flow software was then used to determine shearing patterns in the soil. Different failure modes were observed for the rolling and braked wheel cases. A quantitative comparison of inching vs. conventional driving was also performed on a full-scale vehicle through a series of drawbar pull tests in the Lunar terrain strength simulant, GRC-1. The effect of tire stiffness was also compared; typically compliant tires provide better traction when driving in soft soil, however its been observed that rigid wheels may provide better thrust when non-rolling. Initial tests indicate up to a possible 40 increase in pull force capability at high slip when inching vs. rolling.