cssi/SciSciGPT-SciSciNet huggingface dataset:
The adjustment experience of first-year international undergraduate students in engineering

To compare the challenges that domestic and international students experience in adjusting to college, we conducted a mixed-methods study of first-year undergraduate engineering students at a large public university in the Midwest. We administered a survey to all first-year engineering students. We conducted separate focus groups of domestic and international first-year students. While the domestic and international students identified similar adjustment issues, international students had more difficulty with making American friends, understanding cultural references, adapting to American food, and becoming acquainted with unfamiliar teaching methods and assignments.
X-ray microscopy of biological objects with carbon kappa and with synchrotron radiation

X-ray micrographs of biological objects have been obtained with a resolution better than 1000 angstroms by using poly(methyl methacrylate) x-ray resist and carbon Kalpha or synchrotron radiation. Synchrotron radiation allows short exposure times; storage rings especially designed as radiation sources and improved x-ray resists would make exposure times under 1 second possible.
Characterization of the Quasi-static Deformation of LAAG Joints Adhering Machined Steel Surfaces

Light Activated Adhesive Gripper (LAAG) workholding technology is a means by which a workpiece is held by adhesive joints that can be instantaneously cured or destroyed, on demand. A LAAG joint is the adhesive bond between the gripper pin and workpiece. Due to the novelty of this concept, no knowledge exists with regard to how LAAG joints deform and fail during quasi-static loading. This paper describes an investigation that was carried out to characterize the strength, ductility, and failure modes of a LAAG joint adhering a machined, steel surface subject to axial loading and shear loading.
Biochemical characteristics of ATP-induced secretion of lysosomal enzymes from rabbit polymorphonuclear leukocytes.

ATP induces a release of the lysosomal enzymes,β-glucuronidase and lysozyme, but not the cytoplasmic marker, lactic dehydrogenase, from rabbit peritoneal polymorphonuclear leukocytes. The release requires a low-ionic-strength medium but not divalent cations. It occurs to a greater extent in the presence of K+ than Na+, is greatly enhanced by cytochalasin B, is temperature dependent, and apparently requires a source of metabolic energy as indicated by its inhibition by deoxyglucose. The release is also inhibited by iodoacetate and the organic mercurial, salyrgan. DFP does not inhibit the release, indicating that esterase activation apparently is not involved. ADP and AMP do not sustain the release, nor do the ATP phosphorate analogs in which a methylene group is substituted for the oxygen between theα andβ phosphate groups or theβ andγ phosphates.
A Phenomenological Study of Spiritual Values in Secular-Based Marriage and Family Therapists

Research is lacking on the spiritual values of secular-based marriage and family therapists, who have the highest percentage of practitioners active in religious or spiritual activities compared to other licensed professionals. Research on lived experiences of secular-based marriage and family therapists who engage the spiritual resources of their clients is sparse. This study attempted to provide qualitative phenomenological research on how spiritual values were considered, incorporated, and utilized by secular-based marriage and family therapists when considering three spiritual-based case scenarios. The themes and patterns of their responses are offered to expand the intersection of family therapy and spirituality.
Prospects for rapid deceleration of small molecules by optical bichromatic forces

We examine the prospects for utilizing the optical bichromatic force (BCF) to greatly enhance laser deceleration and cooling for near-cycling transitions in small molecules. We discuss the expected behavior of the BCF in near-cycling transitions with internal degeneracies, then consider the specific example of decelerating a beam of calcium monofluoride molecules. We have selected CaF as a prototype molecule both because it has an easily accessible near-cycling transition and because it is well suited to studies of ultracold molecular physics and chemistry. We also report experimental verification of one of the key requirements, the production of large bichromatic forces in a multilevel system with significant energy level splittings, by performing tests in an atomic beam of metastable helium.
Resonant neutralization of H ˛ near Cu surfaces: Effects of the surface symmetry and ion trajectory

A comparative study of the resonant charge-transfer process of ${\mathrm{H}}^{\ensuremath{-}}$ in front of plane-model Cu surfaces of symmetries (111) and (100) is performed using a two-dimensional Crank-Nicholson wave-packet propagation approach. Very different electron evolutions near the two surfaces are related to different structures of the respective band gaps and allow for the visualization of electronic interaction mechanisms. It is shown that electrons get localized near the Cu(111) surface due to the reflectivity imposed by the band gap. This enables considerable recapture by the ion. In contrast, ${\mathrm{H}}^{\ensuremath{-}}$ is neutralized more efficiently near Cu(100), for which the surface state is embedded in the bulk valence band. Image states are found to be important intermediaries for charge transfer at smaller ion-surface distances. As a consequence of all these effects, the dynamics of ion neutralization near (111) and (100) surfaces vastly differ to yield quite dissimilar ion-survival probabilities. It is found that while the ion-surface interaction time becomes important at normal incidence, for near-grazing incidences, the point of closest approach to the surface is a crucial determinant of the ion survival.
Fundamental studies on stress-corrosion cracking in iron and underlying mechanisms

Abstract Stress-corrosion cracking (SCC) in Fe and Fe-based alloys is critical to material failure for many applications of these materials. In this paper, the behavior of the Fe Σ3 (1 1 1) grain boundary (GB) is studied under precipitations of S, P, N, C and B to elucidate the effects caused by stress-corrosion, as well as its mechanisms, using first-principles calculations. There are certain locations where impurities tend to segregate more. Some elements, such as C and B, serve as strengtheners, while S, P and N weaken the Fe–Fe interactions at GBs. However, the stress-corrosion failures arise in a variety of ways. The accumulation of S and P results in separation of grains, which in turn gives rise to the intergranular cracking under sufficient stress. Cavities may grow at GBs due to the segregation of N and formation of nitrides; consequently, SCC could propagate through the connection of voids.
Attitudes toward imitation: Classical culture and the modern temper

(1989). Attitudes toward imitation: Classical culture and the modern temper. Rhetoric Review: Vol. 8, No. 1, pp. 5-21.
The conceptual similarity effect in free recall

A sizable facilitative effect of conceptual similarity on free recall was obtained with a mixed-list technique. Subsequent to the first recall, related and unrelated words were learned at the same rate.
Disclosing and responding to cancer “fears” during oncology interviews

Video-excerpts from routine oncology interviews are examined to reveal how patients demonstrate and doctors respond to "fears" about cancer. Vocally and visually, embodied impacts of dealing with dreaded consequences of cancer are apparent when addressing both good and potentially bad cancer news. Even a "brush" with cancer can promote negative and ongoing impacts provoking unresolved illness dilemmas. We reveal how, in the midst of extending answers and initiating concerns, patients exhibit trepidations when volunteering narrative information about their medical history and experience of symptoms. In response, doctors are shown to acknowledge yet exhibit minimal receptiveness to patients' lifeworld disclosures and demonstrations (e.g., redirecting attention away from patients' concerns by offering "textbook" symptoms and related pursuits of biomedical agendas). Discussion focuses on interactional criteria for identifying "fears", patients' lay orientations to medical visits, and implications for refining educational workshops for oncologists.
Biological research in the evolution of cancer surgery: a personal perspective.

During the 19th, and for most of the 20th century, malignant tumors were removed by mutilating radical anatomic dissection. Advances such as anesthesia, asepsis, and blood transfusion made possible increasingly more radical operations. There was no scientific rationale for the operations being performed. Surgery in the 20th century was dominated by the principles of William S. Halsted, who contended that the bloodstream was of little significance as a route of tumor cell dissemination; a tumor was autonomous of its host; and cancer was a local-regional disease that spread in an orderly fashion based on mechanical considerations. Halsted believed that both the extent and nuances of an operation influenced patient outcome and that inadequate surgical skill was responsible for the failure to cure. A new surgical era arose in 1957, when cancer surgery began to be influenced by laboratory and clinical research, with results contrary to Halstedian principles. A new hypothesis resulted in a scientific basis for cancer surgery. Clinical trials supported the thesis that operable cancer is a systemic disease and that variations in local-regional therapy are unlikely to substantially affect survival. Complex host-tumor relationships were shown to affect every aspect of cancer and, contrary to Halsted9s thesis, the bloodstream is of considerable importance in tumor dissemination. Clinical trials also have shown that less radical surgery is justified. Studies have shown that improved survival can be achieved with systemic therapy after surgery. Such therapy can reduce both the incidence of distant disease and the tumor recurrence at the tumor site after minimal surgery. The use of systemic therapy in patients who have no identifiable metastatic disease is a drastic departure from previous strategies. New technological innovations resulting from engineering research have improved the quality of life of patients by eliminating the need for some surgical procedures. Because cancer is apt to be a systemic disease, however, clinical trials are necessary to determine the effect of these modalities on patient outcome. Although technological developments will continue to play a role in cancer therapy, research in molecular biology and genetics will dictate the future status of cancer treatment and, ultimately, the future of surgery. [Cancer Res 2008;68(24):10007–20]
The target in the celestial (Moon) illusion

The visual conditions sufficient to produce the celestrial (moon) illusion do not produce it for all presumably suitable celestial targets. For most observers, the illusion is complete for the moon : Apparent visual angle and apparent physical size are inverse functions of elevation, but apparent distance is a direct function. These features of the illusion are attenuated for star clusters and absent for star pairs. Although, in accordance with modern theories of the illusion, the visual terrain may be necessary for the celestial illusion, it is not sufficient; the visual target itself apparently must display particular features
Comparison of ceramic material effects on the flexural Weibull statistics and fracture of high volume fraction particle reinforced aluminum

Abstract The effects of the ceramic particle material on the flexural Weibull modulus, characteristic flexural strength, and damage parameters of particulate-reinforced metal-matrix composites were studied. Three high volume fill composites were fabricated using the pressure infusion casting technique: they were reinforced with SiC, B4C, and α-Al2O3 particles. Four-point bend testing determined the effects of particle material on flexural strength and elastic modulus. It was found the B4C and SiC composites had similar flexural Weibull modulus, low deflection, and similar damage parameters. The α-Al2O3 reinforced composite had the largest flexural Weibull modulus, highest deflection at failure, and largest damage parameter. Extensive microstructural and SEM fractographs were taken of the as-processes and fractured specimens. The mechanisms leading to the dominant failure modes are discussed.
The Effects of Nonverbal Involvement and Communication Apprehension on State Anxiety, Interpersonal Attraction, and Speech Duration.

This experiment raised the question: will communication apprehension (CA) mediate the effect of nonverbal involvement cues (NVI) on state anxiety, interpersonal attraction and speech duration in information gathering interviews? Subjects, high and low in CA, responded to the questions of three trained interviewers from whom they received either high or low levels of NVI behaviors (i.e. head nods, eye contact, body orientation, etc.). CA did not function as a mediating variable. Rather, main effects were obtained for CA on state anxiety and speech duration and for NVI on interpersonal attraction and speech duration.
Fever Through a Jaundiced Eye

Pyogenic liver abscess (PLA) is an important clinical entity to consider in a patient with fever and abdominal pain. Previously, the condition was difficult to diagnose and treat, but with the introduction of widely available and reliable imaging techniques, its diagnosis has become more straightforward. Although uncommon, PLA should especially be considered in the differential diagnosis for patients with specific predisposing conditions such as underlying biliary tract disease, whether as a result of chronic inflammatory disease or malignancy. The introduction of percutaneous drainage has revolutionized the management of PLA, and thus, this disease has become largely correctable.
Brief and Intensive Behavioral Interventions to Promote Sexual Risk Reduction among STD Clinic Patients: Results from a Randomized Controlled Trial

The purpose of this study was to evaluate the separate and combined effectiveness of brief and intensive interventions for sexual risk reduction among patients at a sexually transmitted disease (STD) clinic. Patients (N =1483; 54% men; 64% African-American; M = 29.2 years old) were recruited from a publicly funded, walk-in STD clinic. Patients completed a baseline assessment, and then were randomized to one of six intervention arms; each arm combined a brief intervention with an intensive intervention. The interventions provided different levels of information, motivational counseling, and behavioral skills training, guided by theory, formative research, and empiric precedent. Follow-up assessments, including STD screening, occurred at 3, 6, and 12 months post-intervention. The results showed that infection rates declined from 18.1% at baseline to 4.5% at 12 months. At a 3-month follow-up, patients reported fewer sexual partners, fewer episodes of unprotected sex, and a lower percentage of unprotected sexual events; they strengthened sexual health knowledge, safer sex attitudes and intentions, and self-efficacy beliefs. No consistent pattern of differential risk reduction was observed among the six intervention conditions, nor was any evidence of decay from 3 to 12-month follow-ups obtained. We conclude that implementing behavioral interventions in a STD clinic was associated with significant reduction of sexual risk behavior and risk antecedents.
A Comparison of Ruleset Feature Independent Packet Classification Engines on FPGA

Packet classification is used in network firewalls to identify and filter threats or unauthorized network access at the application level. This is realized by comparing incoming packet headers against a predefined rule set. Many solutions to packet classification are available, but most of these solutions exploit some features of the rule set in order to minimize the memory footprint of rule set storage. However, when the expected rule set features are not present, feature-reliant solutions may yield poor memory efficiency. In this paper, we focus on two rule set independent packet classification schemes, Ternary Content Addressable Memory (TCAM), a brute force search method, and StrideBV, a bit-vector-based algorithmic solution, to determine which solution is more suited for high performance packet classification. Using rule set sizes ranging from 32 to 2048 (targeted for firewall rule sets), we implement both schemes on a Field-Programmable Gate Array (FPGA) to evaluate their performance. We measure the performance using memory efficiency, resource consumption, throughput and power efficiency metrics for both solutions. The post place-and-route results on a state-of-the-art FPGA reveal that StrideBV has 4.5× and 3.5× higher power efficiency in comparison with TCAM, along with 6× and 4× higher throughput when using distributed RAM and block RAM as memory respectively. TCAM has better memory efficiency, though its improvement over StrideBV varies.
Identification of a Novel HSP70-binding Cochaperone Critical to HSP90-mediated Activation of Small Serine/Threonine Kinase

We previously reported the identification of small serine/threonine kinase (SSTK) that is expressed in postmeiotic germ cells, associates with HSP90, and is indispensable for male fertility. Sperm from SSTK-null mice cannot fertilize eggs in vitro and are incapable of fusing with eggs that lack zona pellucida. Here, using the yeast two-hybrid screen, we have discovered a novel SSTK-interacting protein (SIP) that is expressed exclusively in testis. The gene encoding SIP is restricted to mammals and encodes a 125-amino acid polypeptide with a predicted tetratricopeptide repeat domain. SIP is co-localized with SSTK in the cytoplasm of spermatids as they undergo restructuring and chromatin condensation, but unlike SSTK, is not retained in the mature sperm. SIP binds to SSTK with high affinity (Kd ∼10 nm), and the proteins associate with each other when co-expressed in cells. In vitro, SIP inhibited SSTK kinase activity, whereas the presence of SIP in cells resulted in enzymatic activation of SSTK without affecting Akt or MAPK activity. SIP was found to be associated with cellular HSP70, and analyses with purified proteins revealed that SIP directly bound HSP70. Importantly, SSTK recruited SIP onto HSP90, and treatment of cells with the specific HSP90 inhibitor, 17-allylamino-17-demethoxygeldanamycin, completely abolished SSTK catalytic activity. Hence, these findings demonstrate that HSP90 is essential for functional maturation of the kinase and identify SIP as a cochaperone that is critical to the HSP90-mediated activation of SSTK.
On the Singularities in Fracture and Contact Mechanics

Generally, the mixed boundary value problems in fracture and contact mechanics may be formulated in terms of integral equations. Through a careful asymptotic analysis of the kernels and by separating nonintegrable singular parts, the unique features of the unknown functions can then be recovered. In mechanics and potential theory, a characteristic feature of these singular kernels is the Cauchy singularity. In the absence of other nonintegrable kernels, Cauchy kernel would give a square-root or conventional singularity. On the other hand, if the kernels contain, in addition to a Cauchy singularity, other nonintegrable singular terms, the application of the complex function theory would show that the solution has a non-square-root or unconventional singularity. In this article, some typical examples from crack and contact mechanics demonstrating unique applications of such integral equations will be described. After some remarks on three-dimensional singularities, the key examples considered will include the generalized Cauchy kernels, membrane and sliding contact mechanics, coupled crack-contact problems, and crack and contact problems in graded materials.
Doppler-free radiofrequency optogalvanic spectroscopy

Abstract Doppler-free optogalvanic spectra of two neon lines have been observed, with a radiofrequency oscillator used to both excite the discharge and detect the laser-induced change in ion density. Both intermodulated and polarization-intermodulated (POLINEX) methods have been used. The sensitivity is similar to that obtained with fluorescence detection.
Laser beam attenuation and polarization rotation measurement through rocket plumes

There is practically no quantitative information in the open literature to substantiate claims about attenuation of laser beams traversing rocket plumes. This letter gives numerical results for very practical circumstances at typical altitude conditions.
EXTRADURAL DIAMORPHINE FOR POSTOPERATIVE ANALGESIA: AUDIT OF A NURSE-ADMINISTERED SERVICE TO 800 PATIENTS IN A DISTRICT GENERAL HOSPITAL

We report the use of extradural diamorphine for postoperative analgesia as a nurse-based service on selected surgical wards in a district general hospital. Eight hundred patients received lumbar or thoracic extradural diamorphine analgesia for postoperative or traumatic pain. Diamorphine was administered in bolus form by suitably trained nursing staff. Satisfactory analgesia, recorded on a verbal rating scale at the conclusion of the service, was achieved in 94.6% of patients. The technique was considered by medical and nursing staff to be a safe and acceptable method of analgesia. Respiratory depression, defined as a ventilatory frequency of less than 10 b.p.m., occurred in seven patients (incidence of 0.9%). All occurred in the theatre recovery area or in the intensive care unit. Retrospectively, each was predictable and all responded to naloxone 0.4 mg.
Variation in size at sex-change among natural populations of the protandrous hermaphrodite, Crepidula fornicata (Gastropoda, Calyptraeidae)

Protandrous hermaphrodites are predicted to change sex from male to female when relative reproductive fitness of females surpasses that of males. How size at sex transition varies with population, mating group and individual parameters was investigated for five populations of the protandrous hermaphrodite slipper snail, Crepidula fornicata. The populations varied for density, size distribution, average mating group size and sex ratio. Size at sex-change was correlated with the population sex ratio. Comparisons of multiple hypotheses revealed that variables predicting the sex of a snail vary among positions in the mating group. The variables included body size, the relative size of the snail sitting atop the focal snail and population density. Our data support the conclusions that size at sex-change (and by inference, the size at which one sex has relatively greater fitness) is not fixed for these hermaphrodites and that individual size, social conditions and population differences all influence variation in relative fitness.
Ultrastructure of the Flagellar Apparatus and Attachment of Herpetomonas ampelophilae in the Gut and Malpighian Tubules of Drosophila melanogaster1

Electron microscopy was used to examine the flagellar apparatus of Herpetomonas ampelophilae from the gut and malpighian tubules of Drosophila melanogaster. The flagellates attach to the microvilli either by weaving their flagella between the microvilli or by engulfing several microvilli with an external flagellar membrane. The first type predominated in the gut while the second type was limited to the malpighian tubules. Desmosomes were not involved in either type of attachment. A subpellicular collar with emerging microtubules was found to be adjacent to the desmosome of the flagellar pocket of herpetomonads in the gut.
Individual Responses to Lighting Parameters for a Population of 235 Observers of Varying Ages

The authors present the results of a comprehensive study of the effects of observer age upon various relationships between lighting parameters, task visibility, and dynamic visual performance. Included are studies of the effects of age (a) in reducing effective task visibility by increasing visibility threshold, (b) in increasing visibility needs for equal visual performance, (c) in increasing the benefits of increases in the level of illumination due to changes in the shape of the RCS function of luminance, (d) in suggesting use of substantially higher levels of illumination to compensate for losses in the transmittance of the ocular media, and (e) in increasing sensitivity to the disability glare effect, thus emphasizing an increase in the importance of lighting quality for older observers. Of perhaps special interest is the finding that disability glare effect is more than 1.5 times as great a detriment to visual performance in night driving as had been previously supposed.
An electrical model of the vertebrate photoreceptor cell

Abstract An electrical model of the vertebrate photoreceptor cell is presented which accounts for the similar configuration and polarity of the intracellularty recorded photoreceptor potential (IPP) and the P III component of the electroretinogram. It is proposed that during illumination the outer segment actively hyperpolarizes causing current to flow in a vitread direction between the photoreceptor cells and inward across the inner segment membrane. The resulting extracellular IR drop accounts for the P III, while the IR drop across the inner segment membrane accounts for the hyperpolarizing IPP. The model is partly based on the observations that the resistance of the inner segment membrane increases during illumination, and that the amplitude of the IPP decreases during passage of depolarising current and increases during passage of hyperpolarizing current. These results indicate that the IPP is generated across a membrane other than that impaled by the microelectrode, probably in the outer segment. The model further suggests that the trans-retinal d.c. potential is due to a potential difference between the outer and inner segments resulting from a greater membrane polarization of the latter in the unilluminated state. Finally, an explanation is offered to account for pre-synaptic lateral inhibition at the photoreceptor cell level.
Work in progress - a mobile computing collaborative framework for problem-based learning environment

Problem-based learning (PBL) is an important and effective learning technique. The increasing speed and capacity of computing and wireless communication and the decreasing costs of hardware components has made mobile personal computing a viable platform solution to the barriers incurred in the typical PBL process. Wireless infrastructures are becoming a standardized commodity. This paper deals with the development of various design principles, and methods that emphasize the effective integration and utilization of mobile solutions to construct efficient, robust, and reusable software modules in the context of a university's learning environment in computer engineering. A mobile personal software system framework has been developed and prototyped. The system framework supports several important factors involved in a PBL environment, such as resource sharing, cross-functional teamwork, and efficient information distribution. A mixture of modern personal pocket and tablet PCs, Wi-Fi and Bluetooth technology is used for the platform
Mesoporous isocyanurate-containing organosilica–alumina composites and their thermal treatment in nitrogen for carbon dioxide sorption at elevated temperatures

Composite mesostructures consisting of organosilica with isocyanurate bridging groups and alumina have been synthesized using evaporation-induced self-assembly (EISA) in the presence of a triblock copolymer, Pluronic P123, in absolute ethanol solution. These mesostructures were prepared using aluminum isopropoxide and aluminum nitrate nonahydrate as alumina precursors and tris[3-(trimethoxysilyl)propyl]isocyanurate (ICS). The triblock copolymer was removed by extraction with 95% ethanol solution followed by additional thermal treatment of the extracted sample at 300 °C in flowing nitrogen; this process assured a complete removal of the polymeric template without degradation of the ICS bridging groups. The use of aluminum nitrate nonahydrate and a N-containing ICS precursor with a small amount of 3-aminopropyltriethoxysilane (AP) led to the hybrid materials with well-developed porosity and high specific surface area (200–450 m2 g−1). A controlled heating of these materials in nitrogen resulted in N-doped alumina–silica mesostructures showing high affinity towards CO2 at elevated temperatures. The use of inexpensive aluminum nitrate instead of aluminum alkoxides in the EISA synthesis had a significant impact on the pore structure, surface area and adsorption properties of the resulting composite materials.
Neurophysiological changes in caudate nucleus and substantia nigra following morphine treatment.

Abstract Average sensory evoked responses were recorded simultaneously from the caudate nucleus and substantia nigra of freely moving rats. Permanent semi-microelectrodes were implanted 6–8 days before experiments were begun. The acoustic average evoked responses to 32 successive click stimuli in caudate nucleus and substantia nigra consisted of large amplitude potentials of long duration made up of 5 components (P1, N1, P2, N2 and P3) with long latencies. Three different dosages of morphine were examined (10, 30 and 50 mg/kg. i.p.). Evoked response amplitudes were increased or decreased or, in several cases, not altered by morphine. In the recording from the caudate nucleus, the responses observed were related to the dosage of morphine and the time after injection. In the recordings obtained from the substantia nigra, dose and time effects of morphine on the responses were not evident. Naloxone (1 mg/kg, i.p.) reversed the morphine effects. The low dose of morphine (10 mg/kg i.p.) increased motor activity, while the highest dose (50 mg/kg, i.p.) caused catalepsy. The possible anatomical circuits involved in this mechanism are discussed.
Decoding the complexity of type I interferon to treat persistent viral infections

Type I interferons (IFN-I) are a broad family of cytokines that are central to the innate immune response. These proteins have long been appreciated for the critical roles they play in restraining viral infections and shaping antiviral immune responses. However, in recent years there has been increased awareness of the immunosuppressive actions of these proteins as well. Although there are many current therapeutic applications to manipulate IFN-I pathways, we have limited understanding of the mechanisms by which these therapies are actually functioning. In this review, we highlight the diversity and temporal impact of IFN-I signaling, discuss the current therapeutic uses of IFN-I, and explore the strategy of blocking IFN-I to alleviate immune dysfunction in persistent virus infections.
Redox regulation of p53 during hypoxia.

The transcription factor p53 can induce growth arrest or death in cells. Tumor cells that develop mutations in p53 demonstrate a diminished apoptotic potential, which may contribute to growth and tumor metastasis. Cellular levels of p53 are stabilized during hypoxia. The present study tested the hypothesis that reactive oxygen species (ROS) released from mitochondria regulate the cytosolic redox state and are required for the stabilization of p53 protein levels in response to hypoxia. Our results indicate that hypoxia (1.5% O2) increases mitochondrial ROS generation and increases p53 protein levels in human breast carcinoma MCF-7 cells and in normal human diploid fibroblast IMR-90 cells. MCF-7 cells depleted of their mitochondrial DNA (ρ° cells) failed to stabilize p53 protein levels during hypoxia. The antioxidant N-acetylcysteine and the Cu/Zn superoxide dismutase inhibitor diethyldithiocarbamic acid abolished the hypoxia-induced increases in ROS and p53 levels. Rotenone, an inhibitor of mitochondrial complex I, and 4,4′-diisothiocyanato-stilbene-2,2′-disulfonate, a mitochondrial anion channel inhibitor, also abolished the increase in ROS signal and p53 levels during hypoxia. The p53-dependent gene p21WAF1/CIP1 was also induced by hypoxia in both MCF-7 and IMR-90 cells without affecting the growth rate of either cell line. In contrast, both cell lines exhibited increases in p21WAF1/CIP1 expression and growth arrest after gamma irradiation. Primary chick cardiac myocytes and murine embryonic fibroblasts also showed an increase in p53 protein levels in response to hypoxia without cell death or growth arrest. These results indicate that mitochondria regulate p53 protein levels during hypoxia through a redox-dependent mechanism involving ROS. Despite p53-induction, hypoxia alone does not cause either growth arrest or cell death.
Discontinuous Galerkin Inspired Framework for Vector Generalized Finite-Element Methods

Discontinuous Galerkin methods have been extensively used in simulations of various electromagnetic problems, in both time and frequency domains. In this paper, we exploit features of these methods to provide a framework that can be used to overcome a fundamental bottleneck in using as well as augmenting the capabilities of vector generalized finite element methods (VGFEM). This approach permits the use of VGFEM for analysis of piecewise inhomogeneous domains without defining additional constraints on basis functions and allows hybridization with other finite element formulations. Interior penalty discontinuous Galerkin method (IP-DGM) is used to enable communication among partitioned domains. We will present several results that demonstrate applications of these hybrid methods as well as their convergence characteristics.
Comment on the theory of work function

A new formula is derived for calculating the work function of jellium. A theorem is proved which shows that this new formula is equivalent to traditional methods, e.g., as given by Lang and Kohn. The new formula shows that the work function is related to the ground-state energy per particle. In addition we comment on a theorem recently proved by Budd and Vannimenus that allows the generalization of our formal result to an exact treatment of jellium; i.e., a treatment in which the exchange correlation energy functional is not approximated by a local density expression.
Evaluation of a Portable Collision Warning Device for Patients With Peripheral Vision Loss in an Obstacle Course.

PURPOSE A pocket-sized collision warning device equipped with a video camera was developed to predict impending collisions based on time to collision rather than proximity. A study was conducted in a high-density obstacle course to evaluate the effect of the device on collision avoidance in people with peripheral field loss (PFL). METHODS The 41-meter-long loop-shaped obstacle course consisted of 46 stationary obstacles from floor to head level and oncoming pedestrians. Twenty-five patients with tunnel vision (n = 13) or hemianopia (n = 12) completed four consecutive loops with and without the device, while not using any other habitual mobility aid. Walking direction and device usage order were counterbalanced. Number of collisions and preferred percentage of walking speed (PPWS) were compared within subjects. RESULTS Collisions were reduced significantly by approximately 37% (P < 0.001) with the device (floor-level obstacles were excluded because the device was not designed for them). No patient had more collisions when using the device. Although the PPWS were also reduced with the device from 52% to 49% (P = 0.053), this did not account for the lower number of collisions, as the changes in collisions and PPWS were not correlated (P = 0.516). CONCLUSIONS The device may help patients with a wide range of PFL avoid collisions with high-level obstacles while barely affecting their walking speed.
Electroconductive Hydrogels: Electrical and Electrochemical Properties of Polypyrrole‐Poly(HEMA) Composites

Composites of inherently conductive polypyrrole (PPy) within highly hydrophilic poly(2-hydroxyethyl methacrylate)-based hydrogels (p(HEMA)) have been fabricated and their electrochemical properties investigated. The electrochemical characteristics observed by cyclic voltammetry suggest less facile reduction of PPy within the composite hydrogel compared to electropolymerized PPy, as shown by the shift in the reduction peak potential from −472 mV for electropolymerized polypyrrole to −636 mV for the electroconductive composite gel. The network impedance magnitude for the electroconductive hydrogel remains quite low, ca. 100 Ω, even upon approach to DC, over all frequencies and at all offset potentials suggesting retained electronic (bipolaronic) conductivity within the composite. In contrast, sustained application of +0.7 V (vs. Ag/AgCl, 3 M Cl−) for typically 100 min. (conditioning) to reduce the background amperometric current to <1.0 μA, resulted in complete loss of electroactivity. Nyquist plots suggest that sustained application of such a modest potential to the composite hydrogel results in impedance characteristics that resembles p(HEMA) without evidence of the conducting polymer component. PPy composite gels supported a larger ferrocene monocarboxylate diffusivity (Dappt=7.97×10−5 cm2 s−1) compared to electropolymerized PPy (Dappt=5.56×10−5 cm2 s−1), however a marked reduction in diffusivity (Dappt=1.01×10−5 cm2 s−1) was observed with the conditioned hydrogel composite. Cyclic voltammograms in buffer containing H2O2 showed an absence of redox peaks for electrodes coated with PPy-containing membranes, suggesting possible chemical oxidation of polypyrrole by the oxidant
Essential obstetric care: Assessment and determinants of quality

This paper reports on a study to develop and to apply methods for measuring the quality of essential obstetric care (EOC) in health centers. Based on a Nigerian guideline and an international guideline, and in consultation with local experts in primary care obstetrics, norms were established for equipment, personnel, supplies and the process of EOC, focusing on critical tasks. A combination of assessment methods was used, including observation of tasks performed during intrapartum care; use of data from records of care kept by midwives during the period of observation; use of data from records kept by midwives in the calendar year preceding the period of observation; exit interviews with clients; and inventories of equipment and supplies. Twelve health centers in three Local Government Areas (LGAs) and 360 clients in labor were included in the study. Quality of care was measured quantitatively as a score, calculated for each task and for each delivery in the health center. The results show that the methods developed are useful for: identifying quality score differences among health centers, and the effects of methods of assessment on quality scores; identifying aspects of EOC requiring improvements within each health center; and identifying factors influencing the quality of care, as a basis for effective quality improvement efforts. Regression models show that the most consistent and important predictor of quality scores is the use of printed forms (i.e. routine records of labor) during intrapartum care. Printed forms served as job aids, providing prompts that reminded midwives to perform specific tasks.
Calcium couples flagellar reversal to photostimulation in Chlamydomonas reinhardtii.

SEVERAL recent findings1–3 suggest that the intracellular concentration of free calcium, [Ca]i, has an important role in the regulation of ciliary and flagellar beating. For example, Paramecium extracted with Triton X-100 and reactivated with Mg2+ and ATP swim backwards when the Ca2+ concentration of the test medium, [Ca]0, is raised above 10−6M (ref. 1). Similarly, extracted cells of the typanosomid Crithidia show a reversal in wave propagation that is controlled by Ca ions. In studies on the intact flagellar apparatus isolated from a wall-less mutant of Chlamydomonas reinhardtii, the flagella have been shown to reverse direction of the effective stroke when external [Ca]o is raised above 10−6 M (ref. 3). Electro-physiological evidence indicates that, in Paramecium, reversal of ciliary beating is caused by Ca which enters the cell when the Ca permeability of the membrane is increased4,5. We have investigated whether Ca is involved in the phototactic response and more specifically whether this Ca influx is regulated by the cell membrane. Electrophysiological recording was impractical because of the small size of these cells (< 10 µm), and so the approach was to photograph the light-induced motor responses of cells swimming in solutions containing different concentrations of Ca or Ca-blocking agents. The results demonstrate that the reversed beating response of the flagella depends on Ca. Inhibition of the response by Ca-blocking agents supports the view that reversed beating response of the flagella is coupled to photostimulation by an influx of Ca ions.
The Role of Escherichia coli dnaA Gene and Its Integrative Suppression in M 13 Coliphage DNA Synthesis

An F+ derivative of Escherichia coli E 508 thermosensitive in dnaA function (involved in DNA synthesis initiation), its revertant and an Hfr derivative of E 508(ts) in which the temperature-sensitive phenotype is suppressed by integrative suppression have been compared for their ability to support M 13 phage DNA synthesis at the nonpermissive temperature. Upon infection at the nonpermissive temperature, both the revertant and the Hfr strain support normal phage replication while the temperature-sensitive mutant does not. However, when infection is carried out at a permissive temperature and the temperature is shifted up after infection, phage synthesis occurs in the temperature-sensitive mutant also, but in lesser quantity than in the revertant strain. Analysis of intracellular labeled phage DNA indicates: (a) parental replicative form DNA synthesis is not dependent on dnaA function: (b) progeny replicative form DNA synthesis is strongly inhibited in the temperature-sensitive dnaA mutant at the nonpermissive temperature; (c) progeny single-strand DNA synthesis does not absolutely require dnaA function; (d) progeny single-strand DNA is present in the circular form. The implication of the host DNA replication in M 13 DNA synthesis is discussed.
Multivariate digamma distribution

Digamma distributions are extended to multivariate distributions and their properties are examined. The distributions are closely related to multivariate logarithmic series distributions and will be useful when observed frequency data have too long tail to be fitted by a multivariate logarithmic series distribution.
MAGNETIC INTERACTIONS IN SUPERCONDUCTING LANTHANUM INTERMETALLIC COMPOUNDS.

Abstract Measurements of the electronic specific heat and susceptibility of the superconducting intermetallic compound LaIn 3 indicate that the susceptibility is exchange enhanced by a factor of 5.76. This corresponds to an effective electron-electron interaction of 2.91 eV. Using a simple model for the electronic density of states which postulates a peak in the vicinity of the Fermi energy, we obtain a good fit to the experimental temperature-dependent susceptibility.
Genetic Determinants of Morphine Activity and Thermal Responses in 15 Inbred Mouse Strains

Abstract Mice from 15 standard inbred strains were tested for sensitivity to two effects of acute morphine administration, open-field activity, and body temperature changes, at doses of 0, 4, 8, 16, and 32 mg/kg, IP. Large strain differences were consistently observed, indicating a substantial degree of genetic determination of these traits. For morphine-induced activity, some strains were markedly insensitive to all doses (e.g., C3H/He, CE), while others showed increases and some decreases at the same morphine dose. For thermal responses, one strain was insensitive to all doses employed (C3H/He), while others showed marked hypothermia and some hyperthermia at the same dose. Although strains differed in brain morphine concentrations at time of behavioral testing, pharmacokinetic differences were unrelated to both measures of morphine sensitivity. Correlations among strain means (estimates of genetic correlations) were rather high across doses within each measure, indicating that strain differences to a given effect of morphine were rather stable across doses. This suggests substantial commonality in genetically mediated mechanisms across the dose range used for activity, and also for thermal responses. In contrast, genetic correlations between activity and thermal responses were not significant at any dose, indicating that these two traits are largely genetically independent.
Web survey data collection and retrieval to plan teleradiology implementation

This case study details the experience of system engineers of the Imaging Science and Information Systems Center, Georgetown University Medical Center (ISIS) and radiologists from the department of Radiology in the implementation of a new Teleradiology system. The Teleradiology system enables radiologists to view medical images from remote sites under those circumstances where a resident radiologist needs assistance in evaluating the images after hours and during weekends; it also enables clinicians access to patients’ medical images from different workstations within the hospital. The Implementation of the Teleradiology project was preceded by an evaluation phase to perform testing, gather users feedback using a web site and collect information that helped eliminate system bugs, complete recommendations regarding minimum hardware configuration and bandwidth and enhance system’s functions, this phase included a survey-based system assessment of computer configurations, Internet connections, problem identification, and recommendations for improvement, and a testing period with 2 radiologists and ISIS engineers; The second phase was designed to launch the system and make it available to all attending radiologists in the department. To accomplish the first phase of the project a web site was designed and ASP pages were created to enable users to securely logon and enter feedback and recommendations into an SQL database. This efficient, accurate data flow alleviated networking, software and hardware problems. Corrective recommendations were immediately forwarded to the software vendor. The vendor responded with software updates that better met the needs of the radiologists. The ISIS Center completed recommendations for minimum hardware and bandwidth requirements. This experience illustrates that the approach used in collecting the data and facilitating the teamwork between the system engineers and radiologists was instrumental in the project’s success. Major problems with the Teleradiology system were discovered and remedied early by linking the actual practice experience of the physicians to the system improvements.
Chemical Vapor Deposition Of Silicon Carbide For Large Area Mirrors

CVD-SiC has been identified as the leading mirror material for high energy synchrotron radiation because of its high K/a ratio and its ability to be super-polished to <10 A rms roughness. Technology already exists for depositing SiC over large areas (approximately 70 cm x 20 cm). The CVD process, substrate selection, and mirror design considerations are discussed.© (1982) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Government Policies and Revenue of Dairy Farmers

Abstract The impact of obtaining a balance between production and consumption through a production quota, a price support reduction, and an assessment is analyzed. Production quota would have reduced farmers total revenue by 3.51%, price support reduction would have reduced farmers total revenue by 11.44%, and assessment would have reduced farmers' total revenue by 32.39% if excess production (USDA net removals) had been reduced from 1648 to 480million pounds during the fourth quarter of 1981. Thus, government expenditures would have been reduced 70.87% by quota and assessment and 74.23% by a price support reduction.