cssi/SciSciGPT-SciSciNet huggingface dataset:
Stochastic Stability and Instability of Model Ecosystems

In this work, we initiate a stability study of multispecies communities in stochastic environment by using Ito's differential equations as community models. By applying the direct method of Liapunov, we obtain sufficient conditions for stability and instability in the mean of the equilibrium populations. The conditions are expressed in terms of the dominant diagonal property of community matrices, which is a suitable mechanism for resolving the central problem of 'complexity vs stability' in model ecosystems. As a by-product of this analysis we exhibit important structural properties of the stochastic density-dependent models, and establish tolerance of community stability to a broad class of nonlinear time-varying perturbations.
The Sociology of Mental Health

This handbook describes the ways in which society shapes the mental health of its members and further shapes the lives of those who have been identified as mentally ill. The terms mental health and mental illness encompass a broad collection of cognitive, emotional, and behavioral phenomena. Mental illness includes, for example, the experiences of a person who speaks to a companion whom no one else can see; someone who sits silently in her room, alone, eating little and sleeping less, contemplating death; a person suddenly overwhelmed with intense anxiety for no apparent reason; an individual whose consumption of alcohol makes it difficult for him to hold a job or maintain friendships; the person who is frequently sick with no identifiable physiological disease; and, someone who lies even when the truth would be personally advantageous and feels no remorse when others are injured by his actions. Although the classification of these states as “illness” has been questioned, the very use of the term mental health in the title of this handbook and in the designation of the sponsoring section of the American Sociological Association reflects widespread acceptance of this perspective among sociologists.1
Effects of Cyclic Loading on the Deformation and Elastic-Plastic Fracture Behavior of a Cast Stainless Steel

Abstract : Tests conducted in Japan as part of the High Level Vibration Test (HLVT) program for reactor piping systems revealed fatigue crack growth in a cast stainless steel pipe elbow. Material property data was developed to characterize cyclic deformation, cyclic elastic-plastic crack growth and ductile tearing resistance in the pipe elbow material. The tests conducted included monotonic and cyclic tensile tests, monotonic J-R curve tests, and cyclic elastic and elastic plastic fatigue crack growth rate tests. The cyclic elastic plastic fracture behavior of the stainless steel was the primary concern and was evaluated using a cyclic J-integral approach. It was found that the cast stainless steel was very resistant to ductile crack extension. J-resistance curves essentially followed a blunting behavior to very high J levels. High cycle fatigue crack growth rate data obtained on this stainless steel was typical of that reported in standard textbooks. Low cycle fatigue crack growth rate data obtained on this material using the cyclic J integral approach was consistent with the high cycle fatigue crack growth rate and with a standard textbook correlation equation typical for this type of material. Evaluation of crack closure effects was essential to accurately determine the crack driving force for cyclic elastic-plastic crack growth in this material.
Probabilistic Combinatorial Optimization

The (bounded) generalized maximum satisfiability problem covers a broad range of NP-complete problems, e.g. it is a generalization of INDEPENDENT SET, LINEAR INEQUALITY, HITTING SET, SET PACKING, MINIMUM COVER, etc. The complexity of finding approximations for problems in this class is analyzed. The results have several interpretations, including the following: - A general class of existence proofs is made efficiently constructive. - A class of randomized algorithms is made deterministic and efficient. - A new class of combinatorial approximation algorithms is introduced, which is based on “background” optimization. Instead of maximizing among all assignments we maximize among expected values for parametrized random solutions. It turns out that this “background” optimization is in two precise senses best possible if P≠NP. The “background optimization” performed is equivalent to finding the maximum of a polynomial in a bounded region.
Comparison of air-sealing characteristics of tapered- vs. cylindrical-shaped high-volume, low-pressure tube cuffs.

Background This study aimed at comparing air-sealing characteristics of the new tapered-shaped tracheal tube cuffs with cylindrical tube cuffs. Methods Tracheal tubes with tapered-shaped polyurethane (PU) and polyvinyl chloride (PVC) cuffs as well as standard cylindrical-shaped cuffs made of PU and PVC (Covidien, Athlone, Ireland) were investigated. A tracheal model attached to a test lung was intubated, and cuffs were inflated to 10, 15, 20, 25 and 30 cm H2O. The test lung was ventilated with intermittent positive pressure ventilation at peak inspiratory pressures (PIPs) of 20 and 25 cm H2O. Air leakage was assessed by spirometry and measurement of sevoflurane concentration passing the cuff at the upper cuff border using an anaesthetic gas analyser. Experiments were repeated four times with new tracheal tubes for each run. Statistical comparisons were done using Mann–Whitney U-test with level of significance at P < 0.05. Results The tapered-shaped PVC tube cuff demonstrated a significantly lower air leakage determined by spirometry than the cylindrical-shaped cuff at both PIPs (20 and 25 cm H2O). Similarly, sevoflurane leakage was less with the tapered PVC cuff particularly at higher cuff pressures. With the PU cuff, reduction in air leakage by a tapered-shaped compared with a cylindrical-shaped tube cuff was not significant. Conclusions A tapered-shaped tube cuff considerably improves air-sealing characteristics of PVC tube cuffs and allows thereby reducing cuff pressure required for sufficient ventilation. In tube cuffs made of PU that exhibits superior sealing characteristics compared with PVC, a tapered shape failed to result in a further reduction of air leakage.
Microstructure and Mechanical Properties of Precipitation Hardened Aluminum Under High Rate Deformation

In recent years the shock deformation properties of a precipitation-hardened aluminum alloy (6061-T6) have been investigated extensively with time-resolved wave profile gauges. Studies have revealed complicating features of the shock deformation process not easily explained by existing theories of plastic deformation. Specifically, unusual behavior in the dynamic hardness or strength, post-shock hardness, steady wave viscosity, and post-shock microstructure has been observed over the shock pressure range of range of 1–15 GPa. The deformation structure suggests that microscopic heterogeneity in the deformation and temperature state during dynamic compression may be responsible for the observed effects. We have undertaken a study to correlate the shock compression and quasistatic deformation of 6061-T6 aluminum. Recovered specimens which have been shock loaded are examined metallurgically, and results are compared with both static and dynamic mechanical property measurements. Illuminating correlations are emerging from this study, although an unambiguous determination of the importance of heterogeneous effects is yet to be achieved. A modeling effort of dynamic deformation in aluminum based on heterogeneous deformation and adiabatic thermal trapping is being pursued to guide the experimental effort.
Drugs in Society: Causes, Concepts, and Control

Drugs in Society: Causes, Concepts, and Control, Eighth Edition, focuses on the many critical areas of America's drug problem, providing a foundation for rational decision-making within this complex and multidisciplinary field. Lyman offers a comprehensive big-picture examination of the US drug problem, dealing with drugs, abusers, drug enforcement, and public policy. Organized in three sections: Understanding the Problem, Gangs and Drugs, and Fighting Back, topics covered include the business of drugs and the role of organized crime in the drug trade, drug legalization and decriminalization, legal and law enforcement strategies, an analysis of the socialization process of drug use and abuse, and a historical discussion of drug abuse that puts the contemporary drug problem into perspective. Suitable for upper-level undergraduates in Criminal Justice, Criminology, and related programs, Drugs in Society, Eighth Edition, uses logical organization and strong pedagogy (case studies, focused text boxes with related information, critical thinking tasks) to support learning objectives.
An algorithm to learn causal relations between genes from steady state data: simulation and its application to melanoma dataset

In recent years, a few researchers have challenged past dogma and suggested methods (such as the IC algorithm) for inferring causal relationship among variables using steady state observations. In this paper, we present a modified IC (mIC) algorithm that uses entropy to test conditional independence and combines the steady state data with partial prior knowledge of topological ordering in gene regulatory network, for jointly learning the causal relationship among genes. We evaluate our mIC algorithm using the simulated data. The results show that the precision and recall rates are significantly improved compared with using IC algorithm. Finally, we apply the mIC algorithm to microarray data for melanoma. The algorithm identified the important causal relations associated with WNT5A, a gene playing an important role in melanoma, verified by the literatures.
The Tarasoff dilemma in criminal court

The duty to protect, or Tarasoff duty, has been conceptualized as arising solely in the context of a clinical setting. A recent California Supreme Court ruling in People v. Clark adds legal, clinical, and ethical dilemmas to the oftentimes contentious Tarasoff issue. Though the Tarasoff issue is but a minor legal point in Clark, a possible consequence of Clark is that a Tarasoff warning could be deemed nonconfidential and admissible in a criminal trial. Psychotherapists could therefore be testifying in criminal courts as prosecution witnesses. While the possibility of a chilling effect on patients' disclosure of violent ideation in the context of psychotherapy first caused apprehension after the California Supreme Court's 1976 decision in Tarasoff v. Regents of the University of California, this same Court's ruling in People v. Clark some 14 years later may ensure that this fear finally becomes realized. Language: en
Design of a X/Ku multiband feed antenna for satellite communications

The design of a X/Ku multiband feed antenna is described. Narrowband components from a previously designed Ka/Q band feed were modified to provide 15–25% bandwidth. This feed antenna exhibits a fixed phase center at each band and low cross polarization levels.
Efficient modeling of higher order and longer range geometry statistics

The local feature based approaches have become popular in most vision applications. A local feature captures the local appearance of objects or scenes, and is more robust to environment and view-point changes comparing to features extracted from the entire image. The shape and context information is further captured with the spatial relationships of the local features. Modeling more spatial information usually leads to exponential or polynomial increase of the computational cost. Therefore, the spatial modeling of prior work is limited to neighboring or weak geometry relationships of local features, or is not viewpoint invariant. In this thesis, we propose algorithms that model rich geometry information with little sacrifice of the computational cost. We focus on two main vision problems, the whole image representation and the pixel-level image labeling. For each of them, we present an algorithm that incorporate spatial information to its most popular and basic technique: the Bag-of-Words (BoW) representation and Conditional Random Field (CRF) model respectively. Our proposed algorithm is general enough to be applied to or combined with any other advanced technique, which utilizes BoW or CRF as part of it, to further improve its performance with only little increase of the computational cost. We show example usages of the proposed algorithms in several applications, including object recognition, object localization, image retrieval, activity recognition in videos, and object-based image segmentation. Experiment results show that our approaches improve the performance of the state-of-arts for these applications with only little increase of the computation cost.
Effects of processing conditions on the physical and chemical properties of buckwheat grit cakes.

Buckwheat grit cakes were prepared with a rice cake machine using the following independent variables: tempering moisture contents (15, 17, and 19%, wb), heating temperatures (240, 246, 252, and 258 °C), and heating times (5, 6, 7, and 8 s). Higher moisture, higher heating temperature, or longer heating time produced cakes with a higher cake specific volume. Cakes became lighter in color at a lower heating temperature or a shorter heating time. The hardest cake was produced at 252 °C for 5 s at 19% moisture content. The percent weight loss after tumbling decreased with increasing heating times and heating temperatures. Increased heating time resulted in more expanded products. The average rutin content decreased as the heating temperature or heating time increased. These results suggest that processing conditions, including tempering moisture, heating temperature, and heating time, significantly influenced physical and chemical qualities of buckwheat grit cakes such as specific volume, hardness, integrit...
Is your cold-stream working for you or against you? An in-depth look at temperature and sample motion

It is normally assumed that a commercial gaseous nitrogen cold-stream provides a sample environment near 100 K and that the force of the cold-stream does not induce movement in the sample. As might be expected, the reality is much more complex. Here, an investigation of one cold-stream, starting with the temperature profile, is presented. Using silicon single crystals and flexible mounting loops, an approximate force/vibration profile of the cold-stream is obtained. Results indicate that the center of the temperature profile is offset from the position suggested by the manufacturer-supplied alignment tool and coincides with the area within the cold-stream that has the most consistent force profile. Tests indicate that this region is only about one-third of the width of the cold-stream nozzle opening. To verify that the results were relevant to protein crystallographic data collection, the impact of cold-stream position on the final data quality for lysozyme crystals was analyzed. On the basis of the observations it is recommended that users perform a temperature profile of their cold-streams to ensure proper alignment instead of relying only on the alignment tool for setup. In addition, suggestions are made on what users can look for in data processing to identify problems with loop movement and what users can do to minimize the impact of these problems on their experiments.
Trait Psychology in the Philippines

McCrae's proposal to designate a field of personality traits and culture, coupled with challenges to the trait concept by cultural psychologists, makes relevant a review of trait psychology in a collectivistic culture, the Philippines. Philippine evidence in support of the trait concept includes the following: (a) Filipinos have a rich lexicon of trait terms and use these terms to describe and understand others and their behavior, (b) traits may be an important part of Filipinos' self-concepts, (c) the structure of Filipino traits can be approximated by universal Big Five-like dimensions, (d) trait scores show criterion validity, and (e) some interjudge agreement in trait judgments can be demonstrated. There is some suggestion, however, that criterion validities and interjudge agreement values may be lower in the Philippines than in the United States, providing some support for the view that traits will be less predictive of behavior in collectivistic cultures.
A Random Walk Epidemic Simulation

Abstract An epidemic simulation is presented in which the population occupies a rectangular grid and individuals or germs move about the grid using a two-dimensional random walk. It is shown that the model can simulate the Providence measles data and also a distemper epidemic in ferrets.
Behavioral State Dependency of Neural Activity and Sensory (Whisker) Responses in Superior Colliculus

Rats use their vibrissa (whiskers) to explore and navigate the environment. These sensory signals are distributed within the brain stem by the trigeminal complex and are also relayed to the superior colliculus in the midbrain and to the thalamus (and subsequently barrel cortex) in the forebrain. In the intermediate layers of the superior colliculus, whisker-evoked responses are driven by direct inputs from the trigeminal complex (trigeminotectal) and feedback from the barrel cortex (corticotectal). But the effects of the behavioral state of the animal on the spontaneous firing and sensory responses of these neurons are unknown. By recording from freely behaving rats, we show that the spontaneous firing of whisker sensitive neurons in superior colliculus is higher, or in an activated mode, during active exploration and paradoxical sleep and much lower, or in a quiescent/deactivated mode, during awake immobility and slow-wave sleep. Sensory evoked responses in superior colliculus also depend on behavioral state. Most notably, feedback corticotectal responses are significantly larger during the quiescent/deactivated mode, which tracks the barrel cortex responses on which they depend. Finally, sensory evoked responses depend not only on the state of the animal but also on the orienting response elicited by the stimulus, which agrees with the well known role of the superior colliculus in orienting about salient stimuli.
The application of Premack's generalization on reinforcement to the management of classroom behavior.

Abstract A behavior management procedure was successfully employed in a demonstration school for culturally deprived children to increase appropriate behavior in a second-grade classroom. A free-choice activity time was introduced into the classroom and access to this activity was made contingent upon the prior occurrence of desirable behavior. Data were collected on 19 children twice a day in an individual work time and in a group work time and were coded according to a classroom behavior analysis schedule. There were four experimental conditions: baseline I (prior to the contingency conditions), modification I (free-choice activity time contingent upon the occurrence of appropriate classroom behavior), baseline II (removal of the contingent activity time), and modification II (reintroduction of the contingent activity time). In both classroom functions, the average percentage of desirable classroom behavior increased during modification I when compared with baseline I levels. There behaviors decreased when the contingent activity time was removed, but increased again during the reintroduction of the contingency phase.
MORPHOLOGY, INHERITANCE, AND EVOLUTIONARY SIGNIFICANCE OF SEX REVERSAL IN TRIPSACUM DACTYLOIDES (POACEAE)

Inflorescences of Tripsacum dactyloides (L.) L. (Andropogoneae) are characterized by single female spikelets at one to several basal nodes and paired male spikelets at several nodes above them on each raceme. Female spikelets are one-flowered and male spikelets are two-flowered. A sex form variant was found in a wild population in north central Kansas and classified as T. dactyloides (L.) L. forma prolificum Dayton et Dewald. The variant of this native distant relative of maize (Zea mays L. spp. mays) differs from the normal form by having both pistillate and perfect rather than staminate spikelets in the terminal (tassel) portion of the inflorescence and by having two functional pistillate florets in the basal spikelets instead of one. A recessive major gene at a single locus regulates the change of the inflorescence from monoecious to gynomonoecious. TRIPSACUM DACTYLOIDES (L.) L. (Andropogoneae) is a perennial, warm season bunchgrass which is widely distributed from Connecticut to Kansas and south to Paraguay and adjacent Brazil (de Wet, Harlan and Brink, 1982). Its inflorescences consist of one to several subdigitately arranged racemes. The grass is monoecious with the apical two-thirds to threefourths ofthe racemes composed of male spikelets with one to several female spikelets in the basal portion of racemes which are individually sunken into indurated rachis internodes. The female spikelets are solitary with one functional floret; whereas, male spikelets are born in pairs with two functional florets and the glumes are more or less coriaceous. A variant sex form of T. dactyloides with a gynomonoecious breeding system was found in 1981. The variant has been classified as Tripsacum dactyloides (L.) L. forma prolificum Dayton et Dewald (Dewald and Dayton, 1985). This paper describes the morphology and in
Chiroptical Dissymmetries in Fluorescence Excitation from Single Molecules of (M-2) Helicene Dimers

We report on the single-molecule chiroptical properties of “right”-handed bridged triaryl amine helicene dimers, MH2. Using an experimental setup to precisely define the circular excitation polarization at the sample plane, we investigated the circular dichroic response in luminescence from individual molecules in which induced ellipticity from microscope optics is minimized. Our results comparing circular anisotropies in fluorescence excitation from MH2 and perylene diimide (PDI), an achiral, centrosymmetric chromophore, demonstrate a significant reduction in the breadth of the distribution of circular dissymmetry parameters obtained from modulation of the circularly polarized excitation source (457 nm). For PDI, we observe a symmetric distribution of circular anisotropy parameters centered about zero, with a fwhm of 0.25. For MH2, we observe an asymmetric distribution peaked at g = −0.09, with a slightly larger width as the corresponding PDI distribution. These results indicate that the large dissymmetr...
Bad Jobs, Bad Health? How Work and Working Conditions Contribute to Health Disparities:

In this review, we touch on a broad array of ways that work is linked to health and health disparities for individuals and societies. First focusing on the health of individuals, we discuss the health differences between those who do and do not work for pay, and review key positive and negative exposures that can generate health disparities among the employed. These include both psychosocial factors like the benefits of a high-status job or the burden of perceived job insecurity, as well as physical exposures to dangerous working conditions like asbestos or rotating shift work. We also provide a discussion of the ways differential exposure to these aspects of work contributes to social disparities in health within and across generations. Analytic complexities in assessing the link between work and health for individuals, such as health selection, are also discussed. We then touch on several contextual-level associations between work and the health of populations, discussing the importance of the occupational structure in a given society, the policy environment that prevails there, and the oscillations of the macroeconomy for generating societal disparities in health. We close with a discussion of four areas and associated recommendations that draw on this corpus of knowledge but would push the research on work, health, and inequality toward even greater scholarly and policy relevance.
Fossilized index: the linchpin of trustworthy non-alterable electronic records

As critical records are increasingly stored in electronic form, which tends to make for easy destruction and clandestine modification, it is imperative that they be properly managed to preserve their trustworthiness, i.e., their ability to provide irrefutable proof and accurate details of events that have occurred. The need for proper record keeping is further underscored by the recent corporate misconduct and ensuing attempts to destroy incriminating records. Currently, the industry practice and regulatory requirements (e.g., SEC Rule 17a-4) rely on storing records in WORM storage to immutably preserve the records. In this paper, we contend that simply storing records in WORM storage is increasingly inadequate to ensure that they are trustworthy. Specifically, with the large volume of records that are typical today, meeting the ever more stringent query response time requires the use of direct access mechanisms such as indexes. Relying on indexes for accessing records could, however, provide a means for effectively altering or deleting records, even those stored in WORM storage.In this paper, we establish the key requirements for a fossilized index that protects the records from such logical modification. We also analyze current indexing methods to determine how they fall short of these requirements. Based on our insights, we propose the Generalized Hash Tree (GHT). Using both theoretical analysis and simulations with real system data, we demonstrate that the GHT can satisfy the requirements of a fossilized index with performance and cost that are comparable to regular indexing techniques such as the B-tree. We further note that as records are indexed on multiple fields to facilitate search and retrieval, the records can be reconstructed from the corresponding index entries even after the records expire and are disposed of, Therefore, we also present a novel method to eliminate this disclosure risk by allowing an index entry to be effectively disposed of when its record expires.
Established and potential therapeutic applications of octreotide in palliative care

Octreotide acetate was developed as a pharmacologically stable, long-acting analogue of the hormone somatostatin. Mimicking the actions of somatostatin, octreotide has been used for its antisecretory effects. Randomized control trials have established the efficacy of octreotide for malignant bowel obstruction and for chemotherapy-induced diarrhea. Octreotide has proven to be an effective agent for symptoms of carcinoid syndrome. Newer uses include for bone marrow transplantation, infectious diarrheal syndromes, and management of hepatic metastases. More evidence is needed for the establishment of its efficacy for hypercalcemia, pain, pleural effusions, diarrhea after celiac plexus block, and malignant ascites.
Organic compounds in biomass smoke from residential wood combustion: Emissions characterization at a continental scale

Wood smoke in the atmosphere often accounts for 20–30% of the ambient fine-particle concentrations. In communities where wood is burned for home heating, wood smoke can at times contribute the majority of the atmospheric fine-particle burden. Chemical mass balance receptor models that use organic compounds as tracers can be used to determine the contributions of different emission sources, including wood smoke, to atmospheric fine-particle samples. In order for organic chemical tracer techniques to be applied to communities across the United States, differences in wood smoke composition that arise from differences in the type of wood burned in various regions must be understood. A continental-scale accounting of particulate organic compound emissions from residential wood combustion has been constructed which helps to quantify the regional differences in wood smoke composition that exist between different parts of the United States. Data from a series of source tests conducted on 22 North American wood species have been used to assemble a national inventory of emissions for more than 250 individual organic compounds that are released from wood combustion in fireplaces and wood stoves in the United States. The emission rates of important wood smoke markers, such as levoglucosan, certain substituted syringols and guaiacols, and phytosterols vary greatly with wood type and combustor type. These differences at the level of individual wood type and combustion conditions translate into regional differences in the aggregate composition of ambient wood smoke. By weighting the source test results in proportion to the availability of firewood from specific tree species and the quantities of wood burned in each locale, it is possible to investigate systematic differences that exist between wood smokes from different regions of North America. The relative abundance of 10 major wood smoke components averaged over the emissions inventory in different regions of the United States is computed and then used to illustrate the extent to which wood smoke composition differs from region to region in North America.
Enhanced 3D fluorescence live cell imaging on nanoplasmonic substrate

We have created a randomly distributed nanocone substrate on silicon coated with silver for surface-plasmon-enhanced fluorescence detection and 3D cell imaging. Optical characterization of the nanocone substrate showed it can support several plasmonic modes (in the 300–800 nm wavelength range) that can be coupled to a fluorophore on the surface of the substrate, which gives rise to the enhanced fluorescence. Spectral analysis suggests that a nanocone substrate can create more excitons and shorter lifetime in the model fluorophore Rhodamine 6G (R6G) due to plasmon resonance energy transfer from the nanocone substrate to the nearby fluorophore. We observed three-dimensional fluorescence enhancement on our substrate shown from the confocal fluorescence imaging of chinese hamster ovary (CHO) cells grown on the substrate. The fluorescence intensity from the fluorophores bound on the cell membrane was amplified more than 100-fold as compared to that on a glass substrate. We believe that strong scattering within the nanostructured area coupled with random scattering inside the cell resulted in the observed three-dimensional enhancement in fluorescence with higher photostability on the substrate surface.
Involvement of microtubules in lipoprotein degradation and utilization for steroidogenesis in cultured rat luteal cells.

Cells isolated from superovulated rat ovaries metabolize low density lipoprotin (LDL) and high density lipoprotein (HDL) of human or rat origin and use the lipoprotein-derived cholesterol as a precursor for progesterone production. Under in vitro conditions, both lipoproteins are internalized and degraded in the lysosomes, although degradation of HDL is of lower magnitude than that of LDL. In this report we have examined the role of cellular microtubules in the internalization and degradation of human LDL and HDL in cultured rat luteal cells. The microtubule depolymerizing agents colchicine, podo-phyllotoxin, vinblastine, and nocodazole as well as taxol, deu-terium oxide, and dimethyl sulfoxide, which are known to rapidly polymerize cellular tubulin into microtubules, were used to block the function of microtubules. When these antimicrotubule agents were included in the incubations, degradation of the apolipoproteins of [125I]iodo-LDL and [125I]iodo-HDL by the luteal cells was inhibited by 50–85% compared...
Heat checking in the contact zone of a bearing seal (a two-dimensional model of a single moving asperity)

Abstract When two bodies are in sliding contact under heavy loads, local high temperature may occur as a result of excessive frictional heating near the contacting surfaces. Because of a combination of thermal heating and the mechanical load, the material may crack in the neighborhood of the contact zone. This phenomenon is called heat checking. It commonly occurs in mechanical seals and brakes. In recent years there has been increased emphasis on finding a solution. In this paper a simple model is proposed to determine those parameters which can be optimized to control the heat checking of the materials. Because of the size difference between the contact area and the seal, the mathematical model is represented by a half-space subjected to a fast-moving load which is distributed over a small area. The load comes from a combination of an arbitrarily distributed heat source and mechanical loads of pressure and friction. The general solutions are expressed in the form of integral equations with determined Green's functions. Numerical results for fracture criteria are then obtained using a computer program. For the current problem, a nominal pressure of 365 MPa (53000 Ibf in −2 ) and a corresponding friction of 183 MPa (26500 Ibf in −2 ) are used. The induced heat source is 1.5 × 10 7 in Ibf in −2 s −1 (1.70 × 10 6 J m −2 s −1 ). Such a load results in fracture where the crack is first initiated immediately beneath the surface at the trailing edge of the moving load.
A comparison of the norris and killip coronary prognostic indices

Abstract Of the two most frequently used indices for classifying prognosis of patients with an acute myocardial infarction, the Killip index, because of its greater simplicity, is sometimes used instead of the more complicated and time consuming Norris index. The purpose of the current research was to correlate the classification of patients on the two indexes, and to determine reasons for disagreements in classification. Study patients for this comparison included 151 patients who died of a myocardial infarction and who were matched to each of 151 survivors for age, sex, race, and date of hospitalization. Pertinent data were extracted from each patient's medical record by specially trained research technicians. The results indicate that many patients were “misclassified”: 40% of the deaths were placed in the two lowest severity classes using the Killip scale, and 12% using the Norris index. Good agreement was found for comparisons between the 4-category Killip scale and the continuous scale Norris index (Jaspen's multiserial r = 0.67), but only fair agreement was noted when the Norris index was arranged into ordinal categories. Deficiencies in the Killip index included absence of crucial clinical features with prognostic power (e.g. age, systoloic blood pressure, infarct location), while the Norris index was deficient in its requirement for a chest radiograph to estimate the presence of pulmonary edema and of cardiac enlargement. If future prospective studies confirm our analysis, research findings which have been based on one or the other of these indices should not be interpreted similarly.
The compleat modeler applications of calculus in medicine and biology an MATC Course at Dartmouth College

This paper describes a successful course in mathematical biology at Dartmouth College. The course targets premedical students and biology majors, rather than mathematics majors, and requires only one semester of calculus as prerequisite. Real world problems form the basis of student work.
A comparison of two water potential predictors for use in plant and soil thermocouple psychrometry

A linear and a non-linear equation for predicting soil and plant water potentials as measured by thermocouple psychrometric techniques were compared. The non-linear predictor was often just as accurate as the linear predictor. The non-linear predictor did not predict positive water potentials. The non-linear predictor was most accurate in the range of zero to 10 negative bars water potential range. The linear predictor was more accurate than the non-linear predictor when water potentials were larger than −30 bars.
Atypical imaging appearance of toxoplasmosis in an HIV patient as a butterfly lesion

In acquired immunodeficiency syndrome (AIDS) patients, differentiating toxoplasmosis and primary central nervous system (CNS) lymphoma remains a clinical and radiographic dilemma. The presence of butterfly lesions crossing the corpus callosum is customarily used to exclude the possibility of toxoplasmosis. We present an AIDS patient who had Epstein-Barr virus (EBV) polymerase chain reaction (PCR) -positive cerebrospinal fluid studies with a butterfly toxoplasmosis lesion confirmed by multiple methods signifying the importance of including toxoplasmosis in the differential diagnosis of butterfly lesions.
Helical Buckling of Pipes in Extended Reach and Horizontal Wells—Part 2: Frictional Drag Analysis

This paper studies the frictional drag of helically buckled pipes (drillstring and tubing) in extended reach and horizontal wells to correctly predict the actual bit weight or packer load, in cases where helical buckling of pipes may have occured. Helical buckling of pipes in such wells may occur, since large axial loads are often required. The differential equation of axial force balance with consideration of the axial friction for helically buckled pipes is resolved, and the solution shows that when the pipes are helically buckled, the frictional drag will become very large. The actual bit weight for drilling or packer load for well completion may therefore become much smaller than estimated under the unbuckled pipe conditions.
Feasibility of accelerated partial breast irradiation in a large inner-city public hospital.

Breast conserving therapy (BCT) that include breast conserving surgery followed by adjuvant radiation therapy has revolutioned medicine by allowing women to avoid mastectomy. Accelerated partial breast irradiation (APBI) has emerged as a valid alternative to whole-breast irradiation that requires a shorter time commitment. We report our novel experience with APBI at a large public hospital that serves low-income and potentially noncompliant patients. A retrospective chart review was conducted of women who underwent BCT for stage 0–IIA breast cancer from August 2007 to August 2010 treated with APBI with a brachytherapy catheter. Twenty-four patients (20 African American) were considered for APBI. Average age was 61 years. Four patients could not undergo APBI for technical reasons and completed whole-breast irradiation over a 5 week period. Median follow-up was 19 months. Nine patients (37.5 %) had ductal carcinoma-in-situ, and 15 patients (62.5 %) had invasive ductal carcinoma with an average tumor size of 1.1 cm. All patients had negative margins of >2 mm. Two patients (8 %) treated with the brachytherapy catheter had in-breast tumor recurrence. Thus, all 24 patients initially identified for APBI successfully completed adjuvant radiotherapy. Patient compliance with postoperative irradiation is key to minimize local recurrence after BCT for breast cancer. This success with a brachytherapy catheter in underserved women in a U.S. public hospital setting indicates that outcomes of compliance and complications are comparable to nationally published results.
The constitution of the order centrospermae: rRNA-DNA hybridization studies among betalain- and anthocyanin-producing families

Abstract Ribosomal RNA homologies and the thermal stabilities of rRNA/DNA hybrids among ten species of the Centrospermae (including three from the family Caryophyllaceae and seven from five betalain-producing families), three other angiosperms, and one fern, suggest that the betalain-producing families are phylogenetically closer to each other than to the anthocyanin-producing families which are examined.
Electron microscopic observations of the saliva-dependent aggregation of oral streptococci

Abstract Cells of Streptococcus sanguis strain H7PR3 or Streptococcus mitis strain 26 aggregated in the presence of clarified whole saliva. Electron micrographs revealed the presence of two types of extracellular structures which were not detected in sections of control cells that were incubated without saliva, or in non-aggregating preparations in which cells were mixed with saliva plus ethylenediaminetetraacetate (EDTA). The sanguis-aggregating factor consisted of a round, globular component as well as an asymmetrical, fibrillar unit. The mitis factor appeared only as a globular structure. The dimensions and shapes of the aggregating factors were consistent with their known high molecular weights and, also, with the appearance of some of the intercellular matrix constituents of whole plaque.
Regression of Peripapillary Choroidal Neovascularization after Oscillatory Transpupillary Thermotherapy and Anti-VEGF Pharmacotherapy:

Purpose We prospectively evaluated a new treatment for recalcitrant choroidal neovascularization (CNV) in 4 patients. We used an infrared laser (810 nm) in oscillatory thermotherapy (OTT) mode combined with indocyanine green (ICG) dye, utilizing the beneficial effect of both thermotherapy and photodynamic therapy. We describe preliminary experiences with ICG-assisted OTT (I-OTT) combined with intravitreal bevacizumab/dexamethasone for refractory peripapillary CNV resistant to standard therapy. Methods Clinical examination, funduscopy, fluorescein angiography, and optical coherence tomography were performed at baseline and postoperatively. Infrared laser spot size was approximately one-half the lesion size (oscillation 2-3 Hz). Intravitreal injections of bevacizumab (1.25 mg) and dexamethasone (1000 µg) were done during the same visit. Results Mean follow-up was 12.5 months (range 5-17). Mean energy level was 325 mW (range 200-500) in oscillatory mode (2-3 Hz/sec) pre- and post-ICG infusion. Indocyanine green dose was approximately 1 mg/kg (75 mg/patient). All patients had a single treatment. Mean visual acuity improved in 1 patient from 20/60 to 20/30 and remained the same in the other 3 (20/20, 20/40, and 20/400). At final examination, there was no evidence of clinical or angiographic activity of CNV. Conclusions Indocyanine green-assisted OTT has the potential to treat CNV in wet age-related macular degeneration. It may reduce thermal side effects and eliminate or reduce the need for frequent intravitreal treatment. We postulate that I-OTT has a synergistic effect of thermal energy combined with a weak photosensitizer (ICG) applied in an individualized manner, which minimizes thermal damage to retinal and choroidal tissue. Additional anti-vascular endothelial growth factor pharmacotherapy enhances the effect of I-OTT on abnormal new vessels.
An 11.1 Gb/s WDM/TDM-PON system with 100 km reach using ultra-low loss fiber and duobinary downstream signals

We demonstrate an 11.1 Gb/s WDM/TDM-PON system with 100 km reach and 1:128 wavelength split ratio without in-field amplification or dispersion compensation based on ultra-low loss fiber (0.17 dB/km) and duobinary downstream transmission.
Embryopathic effects of different routes of administration of mercuric acetate in the hamster.

Abstract A comparison was made between 4 modes of administration of mercuric acetate into the pregnant golden hamster on Day 8 of gestation, i.e., intraperitoneal (ip), intravenous (iv), oral (o) and subcutaneous (sc) in respect to induced embryonic damage. The embryos were recovered either 4 or 6 days later and the number of resorption sites and abnormal embryos were recorded. The major manifestations of embryonic damage included an increased resorption rate, and small, retarded, and edematous embryos. Several miscellaneous congenital malformations were also detected. In general these embryopathic effects as well as indicators of maternal toxicity were dose dependent for each mode of administration. Primarily on the basis of equivalent resorption rates the following sequence of decreasing efficacy in producing harmful effects was demonstrated; ip > iv > sc > o. The results are discussed within the general context of the known deleterious effects of mercury on biological systems and the controversy regarding the transmission of inorganic mercury from the pregnant animal to the developing embryo.
The Liberating Flame: Natural Gas Production in Peronist Argentina

AbstractAccounting for more than 50 percent of primary energy consumption, gas is used more extensively in Argentina than in the Netherlands, the United States, or the United Kingdom. However, the ...
When the “Burden of Acting White” is Not a Burden: School Success and African American Male Students

In this article, the author reports the “voices” of four academically successful African American men, in their early 20s, as they explicitly respond, in retrospect, to questions regarding the applicability of the burden of acting White theory to their schooling experiences—responses made after reading research articles written by Signithia Fordham and John Ogbu. In general, the responses from the four men illustrate that they successfully negotiated the burden of acting White, even as they revealed instances in which the theory might have been applied to their schooling experiences. The author argues that the various interpretations and uses of Fordham’s and Ogbu’s (single- and co-authored) theories—and, in part, the theories themselves—failed to escape the lure of oversimplification. In that, the (mis?)interpretations and (mis?)uses often oversimplified the theories, and, in turn, the schooling experiences of Black students (and historically marginalized students in general).
Organizational Development: Description, Issues, and Some Research Results

Organizational development (OD) may be defined as an educational strategy employing experienced-based behavior in order to achieve a self-renewing organization. The growth of OD from sensitivity tr...
The Use of Contemporary Harvest Data as a Means of Thinking about Prehistoric Resource Depression

The presence/absence of faunal remains are often used to suggest that shifts in prey choice reflect resource intensification or depression. The archaeological record, however, is typically incomplete owing to issues of discovery, preservation, and data recovery. Though analysis of faunal assemblages provides some indication of diet breadth, they provide little insight as to the relationship between resource potentials and human population densities. We use contemporary/historic harvest data for southern Idaho to assess relative animal population densities, and to calculate potential return rates for deer that are well represented in the archaeological record of the Snake River Plain. In addition, we examine human population densities as the basis for relating possible resource potentials to return rates.
How we do it: posteromedial supine approach to the medial tibial plateau surgical and anatomic approach

Introduction The high frequency and complexity with which the posteromedial fragment in tibial plateau fractures presents provide surgeons with a complex problem. Multiple approaches for the fixation of this fragment have been proposed. We describe a posteromedial approach for direct access to the medial tibial condyle that allows for direct visualization while preserving soft tissue
Tectonic history of the Tharsis Region, Mars

The faults of the Tharsis region of Mars have been mapped and delineated on the basis of age. The orientation of each group of faults was analyzed to determine if they were radial to a point. The results indicate that there are at least four discrete centers of faulting within the Tharsis area which are of significantly different age. The four centers proposed are, from oldest to youngest, (1) in the Thaumasia highlands, (2) in northern Syria Planum, and finally, (3) and (4) near Pavonis Mons. While episodes 3 and 4 occupy the same geographic position, they are separated in time by the development of the Tharsis lava plains and shields. Each episode of tectonism was separated from the next by a period of major basaltic volcanism. The tectonic features of the Tharsis area are thus viewed as being the cumulative result of the superposition of several discrete episodes of faulting, rather than the result of one episode about a single point.