cssi/SciSciGPT-SciSciNet huggingface dataset:
Gravity driven current during the coalescence of two sessile drops

Coalescence of liquid drops is critical in many phenomena such as emulsion stability, inkjet printing, and coating applications. For sessile drops on a solid surface, the coalescence process is more complicated than the coalescence of drops suspended in a fluid medium as a result of the coupling of the contact line motions to the fluid flow. In this paper, we use video microscopy to track the evolution of the interfaces and contact lines as well as the internal fluid motion within a merged sessile droplet. In this study, the fluids in the coalescing drops are miscible and have similar surface tensions and drop volumes but different viscosities and densities. Coalescence occurs in three stages. During the first stage, rapid healing of the bridge between the drops occurs just after they touch. In the second stage, slower rearrangement of the liquids occurs. We show that these intermediate rearrangements are driven by gravity even for density differences of the two fluids as small as 1%. For the systems examined, little to no mixing occurs during these first two stages. Finally, in the third stage, diffusion leads to mixing of the fluids. Dimensional analysis reveals the scaling of the intermediate flow behavior as a function of density difference and geometric dimensions of the merged drop; however, the scaling with viscosity is more complicated, motivating development of a lubrication analysis of the coalescence problem. Numerical calculations based on the lubrication analysis capture aspects of the experimental observations and reveal the governing forces and time scales of the coalescence process. The results reveal that internal fluid motions persist over much longer time scales than imaging of the external interface alone would reveal. Furthermore, nearly imperceptible motions of the external composite drop interface can lead to important deviations from the predominant gravity current scaling, where viscous resistance of the lighter fluid layer plays a significant role in the internal fluid motion.
Dynamics of Human Head and Eye Rotations Under Donders' Constraint

The rotation of human head and the eye are modeled as a perfect sphere with the rotation actuated by external torques. For the head movement, the axis of rotation is constrained by a law proposed in the 19th century by Donders. For the saccadic eye movement, Donders' Law is restricted to a law that goes by the name of Listing's Law. In this paper, head movement and saccadic eye movement are modeled using principles from classical mechanics and the associated Euler Lagrange's equations (EL) are analyzed. Geodesic curves are obtained in the space of allowed orientations for the head and the eye and projections of these curves on the space S2 of pointing directions of the eye/head are shown. A potential function and a damping term has been added to the geodesic dynamics from EL and the resulting head and eye trajectories settle down smoothly towards the unique point of minimum potential. The minimum point can be altered to regulate the end point of the trajectories (potential control). Throughout the paper, the restricted dynamics of the eye and the head movement have been compared with the unrestricted rotational dynamics on SO(3) and the corresponding EL equations have been analyzed. A version of the Donders' Theorem, on the possible head orientations for a specific head direction, has been stated and proved in Appendix I. In the case of eye movement, Donders' Theorem restricts to the well known Listing's Theorem. In Appendix II, a constraint on the angular velocity and the angular acceleration vectors is derived for the head movement satisfying Donders' constraint. A statement of this constraint that goes by the name “half angle rule,” has been derived.
Topic XP : Exploring topics in source code using Latent Dirichlet Allocation

Acquiring general understanding of large software systems and components from which they are built can be a time consuming task, but having such an understanding is an important prerequisite to adding features or fixing bugs. In this paper we propose the tool, namely Topic XP , to support developers during such software maintenance tasks by extracting and analyzing unstructured information in source code identifier names and comments using Latent Dirichlet Allocation. Topic XP enables developers to gain an overview of a software system under analysis by extracting and visualizing natural language topics, which generally correspond to concepts or features implemented in software classes. Topic XP is implemented as an open-source Eclipse plug-in, which proposes interactive visualization of topics along with structural dependencies between underlying classes implementing these topics. The paper also presents the results of a preliminary user study aimed at evaluating Topic XP .
Vitamin A Supplementation and Health Outcomes for Children in Nepal

Purpose: To compare vitamin A supplementation status of children age 6-60 months to the prevalence of vitamin A deficiency disease malnutrition diarrhea and acute respiratory infection. Methods: The nutritional status of children was estimated using mid-upper-arm circumference measurements. A trained ophthalmology assistant assessed for clinical signs of vitamin A deficiency disease. A trained female community health worker interviewed mothers about child health status using a standardized questionnaire. Results: Compared to children who did not receive supplements children who received vitamin A supplements regularly had less malnutrition diarrhea and acute respiratory infection regardless of the number of children per household age sex or fathers occupation. Conclusions: Supplementation with vitamin A is necessary twice a year. Children who received a vitamin A capsule only one time were not as protected as were those children who received vitamin A as a regular twice yearly scheduled dose. (authors)
Primate mating systems and the evolution of immune response

White blood cell (WBC) and red blood cell (RBC) counts were examined in a sample comprising 762 specimens, representing 25 genera and 38 species of captive non-human primates. Animals suffering from illnesses exhibited higher WBC counts than healthy specimens sampled during routine health checks. Analysis of basal WBC counts in healthy animals confirmed a positive correlation between higher cell counts and occurrences of multiple partner mating. This finding remained statistically significant after use of comparative analysis of independent contrasts (CAIC) to control for possible phylogenetic biases in the dataset. These findings were confirmed when using relative testis size as an independent index of mating system. By contrast, RBC counts were not significantly affected by health or correlated with mating systems. These studies confirm a correlation between WBC counts and primate mating systems, and extend the findings to include a positive correlation between WBC counts and relative testis size. However, the findings do not prove that a causal relationship between these variables exists. Further research is required to establish the evolutionary causation of basal WBC counts in primates.
Incidence and Factors Associated With Delayed Graft Function in Renal Transplantation at Carlos Van Buren Hospital, January 2000 to June 2008

Delayed graft function (DGF) is defined as the need for dialysis within the first week after renal transplantation, and slow graft function as persistence of serum creatinine concentration of at least 3 mg/dL on day 5 after the procedure. In the present study, we analyzed the incidence and risk factors for DGF at our center. This retrospective study included 106 patients who underwent renal transplantation between January 2000 and June 2008. Of these, 11 patients were excluded. Two of the remaining 95 patients received organs from living donors, and 93 received cadaver organs. Variables analyzed included donor age, cause of death, cause of chronic renal failure, recipient age, method and time of long-term renal replacement therapy, residual diuresis, panel of reactive antibodies (PRA), HLA mismatch, sex compatibility, cold and warm ischemia times, biopsy-confirmed episodes of acute rejection, urine output in the operating room and in the first 24 hours after the procedure, and intraoperative induction therapy. Data were analyzed using the X 2 and Fisher exact tests and analysis of variance, and are given as mean (SD) and frequency. Variables associated with DGF at univariate analysis (P < .05) were divided between risk factors and predictors of DGF for inclusion in logistic regression models. The incidence of DGF was 32.6%; slow graft function, 16.8%; and immediate graft function, 50.5%. Cold ischemia time longer than 20 hours (P = .02) and donor age (P = .008) were directly associated with DGF. Twenty-four-hour urine output was a strong predictor of DGF. Patients with DGF demonstrated a 25% incidence of an episode of acute rejection before discharge from the hospital. No difference in DGF was observed for use of intraoperative induction therapy.
Studies on the urea cycle enzyme ornithine transcarbamylase using heavy atom isotope effects

Abstract Ornithine transcarbamylase (OTCase) catalyzes the reaction between l -ornithine and carbamyl phosphate in the first step of the urea cycle. 13 C isotope effects were measured in carbamyl phosphate, using OTCase obtained from E. coli in a one-column purification which yielded 30 mg of very pure enzyme from 5 l of cell culture. At near zero l -ornithine, the 13 C kinetic isotope effect was 1.0095, at high levels of l -ornithine (86 mM) the 13 C kinetic isotope effect was unity, and 0.83 mM ornithine was found to eliminate half the isotope effect. These results are indicative of an ordered kinetic mechanism in which carbamyl phosphate binds to the enzyme before l -ornithine. Similar experiments were performed using the slow substrate l -lysine in place of l -ornithine. At 90 mM l -lysine the 13 C kinetic isotope effect was large, 1.076. This value is most likely the intrinsic kinetic isotope effect with this substrate, and the chemistry of the enzyme catalyzed reaction has become rate limiting.
The training programs of the behavior therapy unit at Temple University

Abstract A brief description is presented of the variety of training programs offered in behavior therapy at the Temple University Medical School, followed by a more lengthy description of the most extensive and intensive of these programs — the year-long traineeship. An account of the specific knowledge and skills to be acquired is given, and the general plan and structure of the program. Finally, an evaluation of the strengths and weaknesses of the program is presented.
Optimization of silicon bipolar transistors for high current gain at low temperatures

Bipolar transistors designed specifically for operation at liquid-nitrogen (LN/sub 2/) temperature are discussed. It is found that for high-gain LN/sub 2/ bipolar transistors, the emitter concentration should be around 5*10/sup 18/ cm/sup -3/. Compensating impurities in the base should be kept to minimum. Test bipolar transistors with polysilicon emitter contacts were fabricated using these criteria. The devices show very little current degradation between room temperature and 77 k. Polysilicon emitter contacts are also shown to be somewhat more effective at lower temperatures. >
Five years of tracking heavy ion collisions at RHIC

Abstract Five years have passed since the first collisions of Au nuclei at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) on Long Island. With nucleon–nucleon center-of-mass energies of up to s NN = 200 GeV RHIC provides the highest energy heavy ion collisions at any existing collider. To study the dynamics of nuclear matter at extreme temperatures and pressures hundreds of produced particles need to be tracked and identified, which provides a sizable challenge to the four experiments. This article tries to summarize these first years of RHIC operation from the detector point of view and give a glimpse at the future of the accelerator and its experiments.
Functional verification of the z990 superscalar, multibook microprocessor complex

This paper describes the verification methods and techniques that were established to verify the microarchitecture and architectural correctness of the z990 microprocessor and storage subsystem. The ring-based, four-book storage subsystem links 64 superscalar microprocessors together in this system. The verification process started at the unit level, which focused on the correctness of the microarchitecture, and then proceeded to the element level to verify the architectural correctness of the microprocessor and storage subsystem. After successfully completing element stress testing, the components were combined and verified at the system level. Since the methods used at system-level verification were much the same as the ones used on the CMOS-based IBM S/390® Parallel Enterprise Server G4, the focus of this paper is on the work done at the unit and element levels.
Color flow imaging in children with clinically suspected testicular torsion

32 boys with symptoms of an acute scrotum had testicular sonography with color flow imaging (CFI). Patients ranged in age from 4-15 years (avg = 11 yrs). Symptoms were present from 12 h to 5 days (avg = 42 hrs). CFI correctly predicted presence or absence of testicular perfusion in 11 boys who had surgical exploration of the scrotum. 8 of these 11 patients had hemorrhagic infarction of the testicle, 1 had torsion of the appendix epididymis, 1 had epididymitis, and 1 had bilateral incomplete torsions with normal testicular perfusion. The remaining 21 patients did not have an operation. At least a 1 year follow-up of all patients has shown no clinical evidence of testicular atrophy to suggest a missed diagnosis of torsion. Absence or markedly decreased testicular flow was easily identified and indicates testicular ischemia/infarction. Conversely, hyperemia of the testis and/or epididymis is usually associated with trauma or infection. However, incomplete torsion or spontaneous detorsion may demonstrate normal testicular flow on CFI. Only close correlation of clinical symptomatology and gray scale findings with CFI can identify these patients, who remain at high risk for subsequent complete torsion and infarction.
Recovery in schizophrenia: Reality or mere slogan

As researchers have learned more about schizophrenia, recovery has become an increasingly prominent paradigm for understanding the goals of people with schizophrenia, and for guiding research and services for these individuals. This article provides a review of the recent literature on this topic, with consideration of both the outcome and process perspectives of recovery, and research that supports psychotherapeutic treatment for individuals recovering from schizophrenia. It concludes that schizophrenia can be overcome to varying degrees—some individuals may identify themselves as “fully recovered,” whereas other individuals may be in a process of recovery for their entire lives. In the future, researchers should try to reconcile process and outcome perspectives of recovery, and advocate for recovery-oriented services for individuals with schizophrenia.
Proposed Combustion Strategy for Increasing Thermal Efficiency in Open Chamber Stationary Gas Engines

The quest for high engine brake thermal efficiency (BTE) in medium size (140mm – 190mm bore), lean-burn gas applications becomes increasingly difficult as lower emission levels (250mg/Nm3 NOx) are targeted. A traditional approach to offsetting this negative trend has been to design the piston and the intake ports to create high turbulence and homogeneous mixtures leading to faster combustion burn rates with leaner mixtures. This paper proposes a new combustion strategy aimed at optimizing fuel-air mixture stratification in the main combustion chamber. This would result in maximum fuel concentration within a passive prechamber plug leading to high turbulence flame jet (HTFJ) penetration in the main combustion chamber and, therefore, faster combustion burn rates. Experimental correlation of a combustion model is provided for flame jet ignition in a quiescent, mildly stratified combustion chamber through three different cases. The first case uses a traditional J-gap spark plug; the second, a prechamber plug that is not optimized for the fuel distribution present in this combustion chamber. Finally, the third case makes use of a prechamber plug that has been configured to have properly oriented HTFJ. These three cases constitute the basis of the proposed combustion strategy leading to significant increase in engine brake thermal efficiency (BTE).Copyright © 2009 by ASME
3D positioning germanium detectors for gamma-ray astronomy

We have developed germanium detector technologies for use in the Nuclear Compton Telescope (NCT) - a balloon-borne soft γ-ray (0.2-10 MeV) telescope to study astrophysical sources of nuclear line emission and polarization. The heart of NCT is an array of twelve large volume cross strip germanium detectors, designed to provide 3-D positions for each photon interaction with ~1mm resolution while maintaining the high spectral resolution of germanium. Here we discuss the detailed performance of our prototype 19x19 strip detector, including laboratory tests, calibrations, and numerical simulations. In addition to the x and y positions provided by the orthogonal strips, the interaction depth (z-position) in the detector is measured using the relative timing of the anode and cathode charge collection signals. We describe laboratory calibrations of the depth discrimination using collimated sources with different characteristic energies, and compare the measurements to detailed Monte Carlo simulations and charge collection routines tracing electron-hole pairs from the interaction site to the electrodes. We have also investigated the effects of charge sharing and loss between electrodes, and present these in comparison to charge collection simulations. Detailed analysis of strip-to-strip uniformity in both efficiency and spectral resolution are also presented.
Water quality, trend detection, and causality

This paper begins by discussing the detection of a trend in water quality time series. Using the method of Box and Jenkins, an example of trend identification in sediment loading in the Iowa River is presented. Subsequent to the identification of a trend, an approach is suggested whereby the factors giving rise to the trend can be detected. For the example being considered, it is indicated that the cropping practices in the watershed have a significant impact on the detected trend. Thus, each 1% increase in the area of corn and soybeans planted results in about a 0.42% increase in sediment loading.
Dispersion in channels of arbitrary cross-sections in presence of active surfaces

Abstract This article describes the flow-induced axial dispersion of solutes in conduits of arbitrary cross-sections when the channel wall affects the process due to either adsorption or surface-reaction. The analysis uses a multiple time-scale technique to identify three transport coefficients which characterize the interplays between convection, diffusion and surface-interactions. One of these parameters is well-known diffusion constant recognized in the classical works of Taylor and Aris. In contrast, the other two indicate additional convection and overall slow temporal variation, respectively. Our general formulation obtains these three constants for different commonly seen vessels like the ones with circular, annular, rectangular and elliptical shapes. In case of annular vessels, we consider either inner or outer or both surfaces to be active. Similarly, for rectangle, we repeat the calculations for different numbers of sides involved in the surface interactions. The computed Taylor diffusivity matches with known values for circular and very narrow rectangular conduits. For limiting cases with other geometries, we either derive new exact results or devise novel asymptotic approach based on perturbation analysis yielding useful mathematical expressions for all three transport coefficients. Our computational results are independently verified by these analytical findings when the specific geometric conditions are satisfied.
Factors for seropositivity to leptospirosis in horses

A serological investigation to determine the prevalence of leptospiral antibodies in horses that were admitted to the Ohio State University (OSU) teaching hospital was conducted on 222 serum samples from 204 horses. Sera were included in this study without prior knowledge of the referral complaint or signs at presentation. In addition, 22 horses residing at two farms where there was clinical evidence of equine leptospirosis had sera collected for testing. All serum samples were tested for the presence of antibodies to Leptospira interrogans serovars L. pomona, L. icterohemorrhagiae, L. canicola, L. hardjo, L. grippotyphosa and L. bratislava, using the microscopic agglutination microtiter test (MAMT). Forty-two of the 204 (20.6%) OSU horses and 16 of 22 (72.7%) horses at the two farms were positive (MAMT titer ≥ 1:100) to one or more of the six serovars tested (P<0.001). The most common serovar antigen reacting with serum antibodies was Leptospira interrogans serovar bratislava, with 33 positives (16.2%) among the 204 OSU horses and 15 positives (68.2%) among the 22 farm horses (P<0.001). There were higher proportions of positive titers among females with increasing age, particularly those in the 8–11 year group (P<0.001). Horses presented with eye conditions were more likely to be positive to leptospirosis, and those with laminitis and colic had a higher prevalence than those presented for other conditions (P<0.05).
Nurse Preparation and Organizational Support for Supervision of Unlicensed Assistive Personnel in Nursing Homes: A Qualitative Exploration

Purpose: Nursing supervision of the routine daily care (e.g., grooming, feeding, and toileting) that is delegated to unlicensed assistive personnel (UAP) is critical to nursing home service delivery. The conditions under which the supervisory role is organized and operationalized at the work-unit level, taking into account workloads, registered nurse/licensed practical nurse staffing, and role expectations, are not well understood. The purpose of this paper is to describe the organizational, managerial, and nurse-level factors associated with the nurse's role as supervisor of UAP in nursing homes. Design and Methods: An ethnographic approach to data collection included 31 interviews, 170 hr of observation, and organizational document review at three nursing homes. Analysis included micro-coding and content analysis. Results: Findings revealed (a) considerable variation in organizational resources, systems, and processes to support organization and operationalization of the supervisory role; and (b) limited evidence of nurses' estimation of the potential benefits of training and organizational systems to support supervisory practice and the complexity of the supervisory role. Implications: Delivery of high-quality nursing home care is a matter of national importance, and these findings offer a call to action for nursing home leaders in policy, academia, and ownership and management positions. Nurses must be equipped with competencies and skills that reflect the complex organizational environments in which they work. Additionally, nursing home administrators and managers must be equipped with the competencies and skills needed to effectively and efficiently organize and operationalize care delivery practices to support nurses' role enactment.
Pyrrolidine dithiocarbamate is a potent antioxidant against hypochlorous acid-induced protein damage

The antioxidant potential of the dithiol compound pyrrolidine dithiocarbamate (PDTC) against protein damage induced by hypochlorous acid (HOCl) was investigated. The effects of PDTC were compared to those of reduced glutathione (GSH) and N-acetylcysteine (NAC). PDTC markedly and in a concentration-dependent manner inhibited HOCl-induced inactivation of α1-antiproteinase, protein carbonyl formation on serum albumin and oxidation of human low-density lipoprotein. The direct scavenging of HOCl by PDTC was demonstrated by two quantitative methods, oxidation of ferrocyanide and chlorination of monochlorodimedon. In all assay systems, PDTC was two to three times more potent than GSH and NAC, while diethyldithiocarbamate was about as effective as PDTC. These data demonstrate that PDTC is a potent antioxidant against HOCl-induced protein oxidative damage, suggesting that PDTC might be useful in the prevention and treatment of inflammatory conditions.
Performance analysis of future shared storage systems

This paper deals with the analysis and design of two important classes of computer systems: BIP (Billion Instructions Per Second) systems consisting of a few very high performance processors and KMIP (K Million Instructions Per Second) systems with hundreds of low speed processors. Each system has large, shared semiconductor memories. Simpl analytic models are developed for estimating the performance of such systems. The models are validated using simulation. They can be utilized to quickly reduce the design space and study various trade-offs. The models are applied to BIP and KMIP systems and their use is illustrated using examples.
The immunobiology of placentation.

Summary: : A review of the current theories on the nature of the placental allograft and the evolution of placentation in the presence of a cellular immune response highlights the inability of current hypotheses to explain the success of both invertebrate and vertebrate placentation. Only one theory –“the anatomical separation of the fetus from the mother”– appears relevant. How this separation might develop during implantation is discussed.
Tunable radio frequency photonic filter based on intensity modulation of optical combs

We demonstrate tunable programmable microwave photonic filters based on optical frequency combs. The utilization of optical comb enables to scale multi tap filters to large number of taps. By using optical line-by-line pulse shaping to program tap weights, we shape the filter's bandpass. In contrast to our previous work, we demonstrate a much simplified technique based on intensity modulator biased at its minimum transmission which results in double sideband with carrier suppression. We use a programmable optical delay line to uniformly tune the bandpass filter center frequency uniquely across half of the free spectral range. Our new scheme is very simple and easily implementable which provides filters with arbitrary tap weights. As an example we implement a filter with Gaussian apodized tap weights which we tune over 0–5.2 GHz with sidelobe suppression in the range 26–31 dB.
Differential Subunit Aggregation of a Purified Protein from Cold-hardened and Unhardened Puma Rye

Summary Purified ribulose-1,5-bisphosphate carboxylase-oxygenase from cold-hardened and unhardened Puma rye plants was osmotically concentrated by dialysis against buffer containing 25% (w/v) polyethylene-glycol for 16 h at 4°C in the presence or absence of β-mercaptoethanol. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of protein samples concentrated 100 to 200 fold in the absence of reducing agent indicated that the large subunit of the enzyme from unhardened rye plants aggregated to a greater extent than the large subunit of the enzyme from cold-hardened rye plants. This aggregation was reversed by the addition of β-mercaptoethanol to the concentrated enzyme samples implicating disulfide bond formation in the mechanism of aggregation. No structural alterations were observed by SDS polyacrylamide gel electrophoresis for the small subunits of the enzyme from either cold-hardened or unhardened rye plants. The relevance of these results to Levitt's sulfhydryl hypothesis is discussed.
Adaptation of Tibial Structure and Strength to Axial Compression Depends on Loading History in Both C57BL/6 and BALB/c Mice

Tibial compression can increase murine bone mass. However, loading protocols and mouse strains differ between studies, which may contribute to conflicting results. We hypothesized that bone accrual is influenced more by loading history than by mouse strain or animal handling. The right tibiae of 4-month-old C57BL/6 and BALB/c mice were subjected to axial compression (10 N, 3 days/week, 6 weeks). Left tibiae served as contralateral controls to calculate relative changes: (loaded - control)/control. The WashU protocol applied 60 cycles/day, at 2 Hz, with a 10-s rest-insertion between cycles; the Cornell/HSS protocol applied 1,200 cycles/day, at 6.7 Hz, with a 0.1-s rest-insertion. Because sham loading, sedation, and transportation did not affect tibial morphology, unhandled mice served as age-matched controls (AC). Both loading protocols were anabolic for cortical bone, but Cornell/HSS loading elicited a more rapid response that was greater than WashU loading by 13 %. By 6 weeks, cortical bone volume of each loading group was greater than of AC (average + 16 %) and not different from each other. Ultimate displacement and energy to fracture were greater in tibiae loaded by either protocol, and ultimate force was greater with Cornell/HSS loading. At 6 weeks, independent of mouse strain, the WashU protocol produced minimal trabecular bone and the trabecular bone volume fraction of Cornell/HSS tibiae was greater than that of AC by 65 % and that of WashU by 44 %. We concluded that tibial adaptation to loading was more influenced by waveform than mouse strain or animal handling and therefore may have targeted similar osteogenic mechanisms in C57BL/6 and BALB/c mice.
Coordinated stasis or coordinated turnover? Exploring intrinsic vs. extrinsic controls on pattern

Abstract A number of potential mechanisms have been suggested to explain patterns of coordinated stasis in the fossil record. The major dichotomy of explanation lies between mechanisms emphasizing the maintainance of stability and those emphasizing the patterning role of turnover events. A classification scheme of causes is presented here that breaks the pattern into its two aspects: (1) long term evolutionary and ecological stability and (2) rapid synchronous faunal turnover. Within each, causal mechanisms arising from extrinsic (physical, environmental) and intrinsic (evolutionary or ecological) sources are discussed and their ability to produce different aspects of the coordinated stasis pattern are examined. While exploration of potential causal forces has only just begun, two potential scenarios emerge from this analysis as most promising. Both acknowledge the primacy of the physical environment in driving turnover in some way (extrinsic control), but differ in their explanations for stasis. In one alternative, environmental selection of taxa with similar tolerances leads to persistent associations that track preferred habitats in a “stable” environment until a large disturbance initiates collapse and re-establishment; this mechanism emphasizes extrinsic causes for stasis (or, more aptly put, the lack of extrinsic impetus for change). In the second scenario, internal organization of ecosystems provides resilience to disturbance, allowing persistence of faunal associations and tracking despite a fluctuating environment until a threshold of environmental change is reached, causing collapse and re-establishment; this mechanism emphasizes intrinsic causes for stability. Any explanation, however, must incorporate some intrinsic concept of stability (e.g., incumbency, ecological locking) if the apparent non-invasability of communities is to be accounted for. The concentration of most ecological and evolutionary change (at least on a regional scale) into short discrete bursts suggests either (1) that the extrinsic mechanisms driving turnover operate episodically, or (2) that the environment is changing gradually and continually, but the response of faunas to such change is non-linear. Episodicity is a (necessary?) correlate of the first explanation for stability presented above, but is consistent with both scenarios; gradual change and non-linearity of response suggests that the second explanation (intrinsic stability) is more plausible. Future hypothesis-testing strategies to discriminate between categories of cause for both stasis and turnover should therefore not only include careful examinations of the ecological and evolutionary properties of faunas through time, but also a detailed and quantitative assessment of environmental change in relation to faunal change during the interval in question.
Finite Element Analysis of the Arcan Specimen for Fiber Reinforced Composites under Pure Shear and Biaxial Loading

Linearly elastic finite element analyses were used to examine the effects of fiber orientation, notch angle and notch root radius on the stress distribution in Arcan specimens in order to optimize the specimen geometry for the unidirectional, fiber reinforced composite AS4/PEEK under shear and biaxial loadings. Two fiber orientations, three notch angles and five notch root radii were examined. A comparison between butterfly-shaped and circular S-shaped specimens was also made. For specimens with fibers running across the specimen from grip to grip (1-2 orientation), a 1340 notch angle was found to be the best choice due to superior stress uniformity along the gage section and minimum transverse normal stress along the notch flank. However, specimens with fibers running from notch to notch (2-1 orientation), required a 900 notch angle for optimum stress uniformity along the gage section and minimum transverse normal stress along the specimen notch. It was also found that, along the gage section, the larges...
"Universal Reason" as a Local Organizational Method: Announcement of a Study

This article announces an ethnomethodological study of the formal analytic practices of Tibetan philosophers engaged in the collaborative work of producing correct philosophical debates. Tibetan scholar-monks address themselves to the work of sustaining an argument, providing formal warrants for authorizing truth and correctness, objectivating their accounts and disengaging those accounts from their local organizational practices. At the same time, it is the concern of the Tibetans' dialectics to avoid naive acceptance of reified accounts. The announced study proposes to describe their philosophical activities and to locate what originality may affect resolving the tension between formal analytic work and philosophical insight into truth.
Phase field simulation of ferroelectric and antiferroelectric single crystals

Ferroelectric materials exhibit spontaneous polarization, spontaneous strain and domain structures below the Curie temperature. The phase field approach has been used to simulate the formation of ferroelectric domain structures and the ferroelectric-antiferroelectric phase transformation. The evolution of phases and domain structures was simulated in ferroelectric single crystals by solving the time dependent Ginzburg-Landau (TDGL) equation with polarization as the order parameter. In the TDGL equation the free energy of a ferroelectric crystal is written as a function of polarization and applied fields. Change of temperature as well as application of stress and electric field leads to change of free energy level and therefore evolution of phase and domain states. In this work the temporal evolution of polarization field was computed by solving the TDGL equation with explicit time integration scheme. The finite difference method was implemented for the spatial description of the polarization. Cubic to tetragonal, cubic to rhombohedral and ferroelectric to antiferroelectric (tetragonal or rhombohedral) phase transformations were modeled and the formation of domain structures were simulated. Field induced polarization switching and the macroscopic material responses were simulated.
Visibility in the southwestern united states from summer 1978 to spring 1979

Abstract The Environmental Monitoring Systems Laboratory U.S. Environmental Protection Agency, recognizing the importance of visibility to the experience of a visitor to Class I areas in the United States, entered into an agreement with the National Park Service to initially deploy an experimental research teleradiometer network at 13 national parks and monuments in the Southwest. Objectives of the network are to: (1) evaluate the ability of multiwavelength teleradiometers to measure visibility, (2) evaluate the ability of several physical variables to characterize visibility and (3) determine the temporal and spatial dynamics of visibility deterioration on a regional scale. Visibility is more than the ability to see an object at the distance at which it just disappears. Visibility includes the effects of atmospheric constituents on the ability of an observer to see color, texture, and form of both near and distant vistas. Target apparent contrast and delta contrast are variables that can represent atmospheric visibility, but they are vista specific. Hence, standard visual range, a parameter which tends to normalize differences between targets, remains a useful interpretive parameter for comparing data from different vistas. Each park vista is also monitored with standardized photography, allowing a pictorial description of visibility. Analysis of data from summer 1978 through spring 1979 shows that winter had the highest standard visual range and spring the lowest. Capitol Reef National Park had the best visibility, while Wupatki National Monument had the worst. Visibility on cloudless days was usually better than on cloudless and cloudy days taken together.
Ultrasensitive Bimaterial Cantilevers Optimized for Nanowire Heat Conduction Measurement

We have developed a microcantilever-based technique for measurement of heat conduction through individual nanowires. We fabricated silicon nitride cantilevers with nominal dimensions of length 100 μm, width 2–6 μm, and thickness 130 nm. Cantilever chips are designed with multiple cantilevers spaced at varying distances. With a reflective aluminum coating of optimized thickness, these bimaterial cantilevers can be used as ultrasensitive thermal sensors capable of measuring very small heat flux through a nanostructure fixed between two cantilevers. The ultrasensitive bimaterial cantilevers designed in this work are not limited to heat conduction measurements, but will also be useful for measuring near-field radiative heat transfer between a sphere, attached to the tip of the cantilever, and a flat plate.Copyright © 2012 by ASME
Inhibition of the ethanol and carbon tetrachloride induced fatty liver by antioxidants

Abstract The development of the acute ethanol-induced fatty liver was significantly inhibited by the prior administration of α-tocopherol acetate. Complete inhibition of the ethanol-induced fatty liver was induced by the prior intraperitoneal administration of the antioxidant, N,N′-Diphenyl-p-phenylenediamine (DPPD). DPPD reduced, but did not prevent, the ethanol-induced hepatic-triglyceride accumulation when administered orally simultaneously with ethanol. Significant inhibition of hepatic-triglyceride accumulation in carbon tetrachloride-treated rats, pre-treated with DPPD, was also noted. The CCl4-treated group manifested fatty metamorphosis, central necrosis, polymorphonuclear cell infiltration, and a disruption of the architecture of the reticulum. These changes were markedly reduced in CCl4-treated rats which had received DPPD. Since both the ethanol- and CCl4-induced fatty livers were significantly modified by antioxidant administration, it is suggestive that, to some degree, a common factor is involved in the pathogenesis of fatty livers from these agents. The possible use of antioxidants in the prevention or modification of liver injury is suggested.
Point and Interval Estimation of Variogram Models Using Spatial Empirical Likelihood

We present a spatial blockwise empirical likelihood method for estimating variogram model parameters in the analysis of spatial data on a grid. The method produces point estimators that require no spatial variance estimates to compute, unlike least squares methods for variogram fitting, but are as efficient as the best least squares estimator in large samples. Our approach also produces confidence regions for the variogram, without requiring knowledge of the full joint distribution of the spatial data. In addition, the empirical likelihood formulation extends to spatial regression problems and allows simultaneous inference on both spatial trend and variogram parameters. We examine the asymptotic behavior of the estimator analytically, and investigate its behavior in finite samples through simulation studies.
Optical properties of Cu nanocomposite glass obtained via CuO and SnO co-doping

Prospective applications of plasmonic nanocomposites in photonic and optoelectronic devices demand innovative means of material syntheses, as well as a comprehensive understanding of the influence of material composition and processing on resulting properties. In this work, it is shown that a phosphate glass matrix prepared with stoichiometric amounts of CuO and SnO dopants by the melting technique may well be effective for the precipitation of Cu nanoparticles (NPs) upon heat treatment (HT). Optical absorption and photoluminescence (PL) spectroscopy, including emission decay dynamics, are employed in the characterization of the melt-quenched glass, and for investigating the influence of HT on material optical properties. The as-prepared material appeared highly luminescent; the data suggests contributions from both twofold-coordinated tin centers and Cu+ ions to light emission. The PL depends strongly on excitation wavelength; e.g. excitation at 260 nm shows a blue–white emission for which a significant contribution from tin is indicated, whereas excitation at 360 nm produces an orange emission in association with Cu+ ions. Thermal processing results in the chemical reduction of ionic copper via Sn2+ ultimately producing Cu NPs in the matrix, as evidenced by the appearance of the surface plasmon resonance around 574 nm. As a result, Cu+ PL decreases and the emission band shows a dip due to reabsorption by Cu NPs in resonance.
The thermal denaturation of ribonuclease A in aqueous-methanol solvents.

Circular dichroism was used to monitor the thermal unfolding of ribonuclease A in 50% aqueous methanol. The spectrum of the protein at temperatures below −10°C (pH * 3.0) was essentially identical to that of native ribonuclease A in aqueous solution. The spectrum of the thermally denatured material above 70°C revealed some residual secondary structure in comparison to protein unfolded by 5 M Gdn·HCl at 70°C in the presence or absence of methanol. The spectra as a function of temperature were deconvoluted to determine the contributions of different types of secondary structure. The position of the thermal unfolding transition as monitored by α-helix, with a midpoint at 38°C, was at a much higher temperature than that monitored by β-sheet, 26°C, which also corresponded to that observed by Δ A 286 , tyrosine fluorescence and hydrodynamic radius (from light scattering measurements). Thus, the loss of β-sheet structure is decoupled from that of α-helix, suggesting a step-wise unfolding of the protein. The transition observed for loss of α-helix coincides with the previously measured transition for His-12 by NMR from a partially folded state to the unfolded state, suggesting that the unfolding of the N-terminal helix in RNase A is lost after unfolding of the core β-sheet during thermal denaturation. The thermally denatured protein was relatively compact, as measured by dynamic light scattering.
A socio-technical approach to the planning of emergency medical services

The communlty response to emergency medlcal servlce demands suffers from random pressures and uncoordlnated plannlng desplte the sophlstlcatlon of ava!lable technology. Weaknesses Include lack of a conceptual framework, lack of system performance yardstlcks, tendency toward Isolated slteratlon of elements, emphasis on technlcal to the exclusion of soclal problems, and Inapproprlate geographlc unlts for plannlng.
E-Net: Evolutionary neural network synthesis

Abstract E-Net is a new distributed evolutionary learning system that evolves neural-network-based pattern recognition systems (PRSs) with limited human interaction. This system orchestrates a multiplicity of evolutionary and classical learning techniques to synthesize feature detectors, select sets of cooperative features, and assemble classifiers. Feature detectors are represented as feed-forward neural networks and recognition systems are defined using a collection of networks. E-Net evolves network topologies and trains weights to form accurate recognition systems using a computationally efficient process that gradually extends primitive network topologies to form increasingly discriminating structures. The evolutionary search process effectively explores the space of candidate topologies by manipulating populations of feature detectors and recognition systems using variation operators such as crossover and mutation. The majority of evolutionary learning techniques have been designed to perform parameter optimization. E-Net is designed to perform both synthesis and optimization. Consequently, many novel concepts and techniques are introduced in this research that expedite the gradual synthesis of structure, such as the new multitiered selection process used in E-Net's evolutionary algorithm that avoids premature convergence to complex topological structures.
Oil core NMR imaging/spectroscopy instrumentation

Abstract In this note we briefly review what we see as the essential ingredients of a generalized oil core NMR imaging/spectroscopy system.
On local finite element refinements in multiscale air quality modeling

Abstract Variable resolution is a highly desirable property in air quality models, especially in regional applications. Resolution can be increased in dense source regions by using finite element refinements. Here, the important principles that must be obeyed at refinement boundaries are discussed. Mass conservation is achieved by making the element basis functions continuous. Constraint relations that assure continuity for various refinement ratios are described. A second issue is to keep the refinement boundaries free of noise. Since coarse and fine elements act like different media, aliasing errors usually lead to noise waves. A non-linear filter is used to remove some of this noise. Tests are conducted with different refinement ratios to see the effect of increased resolution on accuracy. In general, refinements increase accuracy by reducing diffusion errors. The peak concentrations are overpredicted during the transition from the fine to the coarse grid. These overpredictions are smaller when the refinements are gradual.
Aliphatic–aromatic copolyesters derived from 2,2,4,4‐tetramethyl‐1,3‐cyclobutanediol

With the massive changes taking place in the world today, the development of new thermally and mechanically stable polymeric materials is of utmost importance. This article focuses on the synthesis and thermal characterization of a new series of copolyesters that incorporate both aromatic as well as aliphatic diols. This is of interest because most polymer materials that exhibit high thermal and/or mechanical properties contain aromatic monomer units only. These aromatic units usually contribute to either the thermal or mechanical properties but typically not both. An example of this is bisphenol A polycarbonate, which has high mechanical properties but only moderate thermal properties when compared, for example, to polyimides. In recent years there has been an interest in copolyesters that contain 2,2,4,4-tetramethyl-1,3-cyclobutanediol (CBDO). This aliphatic monomer imparts some very unique thermal as well as mechanical properties. This article will report the thermal properties of a new series of CBDO-based copolyesters. These polymers include CBDO, a series of bisphenols, and terephthaloyl chloride. The series of bisphenols discussed here include bisphenol A, AF, F, and HPF. These polymers display glass transition temperatures near 200 °C and decomposition temperatures from 390–420 °C (Argon) and from 385–410 °C (Air). © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3473–3478, 2004