cssi/SciSciGPT-SciSciNet huggingface dataset:
Decreased cerebral blood flow during acute hyperglycemia

Cerebral blood flow (CBF) decreases during acute hyperglycemia but the mechanism of this change is unknown. The role that plasma osmolality plays in this effect was reexamined in pentobarbital-anesthetized rats using a continuous measure of CBF, laser-Doppler flowmetry. CBF decreased 25% during acute elevation of plasma osmolality induced by intraperitoneal injection of concentrated solutions of glucose or mannitol. In addition there were brief transient increases of CBF with peak magnitude 2-4-times the baseline level that were not accompanied by transient depression of electroencephalographic activity. These transient CBF increases may explain why discontinuous methods of CBF measurement fail to detect flow decreases after mannitol injection. Decreased CBF measured during acute hyperglycemia may be the result of increased plasma osmolality.
Spatial Gradient Detection of Chemical Cues by Catfish

1. Unrestrained brown bullhead catfish (Ictalurus nebulosus) were trained to turn toward the higher concentration when two concentrations of a mixture of amino acids were simultaneously flowed over the cutaneous taste epithelium on the right and left maxillary barbels. 2. The minimum detectable Weber fraction was dependent upon the stimulus solution concentration with smaller Weber fractions being detected at weaker concentrations. Brown bullheads were capable of detecting a concentration difference of 0.3 Weber fractions at the highest stimulus solution concentration and 0.1 Weber fractions at the lowest. 3. Variations in the time-of-arrival of the stimuli at the two barbels, greater than those occurring during normal testing, did not alter the values of the minimum discernable Weber fraction. This indicates that spatial rather than temporal differences in concentration were the basis of these responses. 4. Anosmic bullheads were as sensitive to concentration differences as intact fish, indicating that discrimination was made using the taste receptors on the barbels. 5. These experiments show that bullheads can compare the intensity of a taste stimulus at two distinct receptor fields and thus define a gustatory chemical space. This ability is a requirement for tropotactic orientation to chemical gradients and suggests that such a mechanism may be important in nature.
Determination of spermatozoan motility

Abstract A rapid method for the quantitative determination of spermatozoan motility is described. This method involves the spectrophotometric measurement of the optical density of sperm suspensions made to flow through a flow-cell so as to orient in the direction of the light path. When the flow is stopped the spermatozoa return to randomness. The time it takes a spermatozoan suspension to return to randomness can be followed spectroscopically and it is directly related to the spermatozoan motility. The motility of sea urchin spermatozoa upon dilution into seawater has been quantitatively determined and found to consist of three distinct periods: (1) short period of high motility without decrease in activity, (2) period of rapid decline in activity (which appears to be exponential), and (3) a variable period of low activity. The effect of EDTA on the 3 periods is also described.
On the possibility of observing a Bose-Einstein condensation of excitons in CdS and CdSe

Abstract It is shown that ideally a Bose-Einstein condensation of excitons ought to be observable in CdSe as a narrowing of the fundamental emission line with increasing concentration above a critical concentration, ∼ 10 16 cm 3 , using available pulsed light sources. It is concluded (with less justification) that the effect ought also to be observable in CdS. Deviations from ideality and their expected effects on conditions required for observation of the condensation and on its existence are discussed.
WE-A-352-01: Quality Assurance Procedures for Digital Radiography

Diagnosticmedical physicists have traditionally played a key role in the radiology department's Quality Assurance (QA) program. Procedures for QA of digital radiography (DR) systems are less well‐established than those designed for conventional screen‐film radiography. Some methods that were appropriate for conventional systems do not yield accurate results for digital systems. Methods that rely on images on film cannot be performed in a facility devoid of chemical processing. Methods that do not consider effects of all stages of the digital imaging chain from acquisition to display are likely to provide erroneous results. Digital systems often do not provide data in a convenient form for assessing performance. Nevertheless, medical physicists are responsible for designing and directing efforts to assure the safety and efficacy of DR. Development of standards for performance verification of digital radiographic systems has been outpaced by commercialization of the technology. Practitioners, operators, vendors, and medical physicists are uncertain as to how to configure, calibrate, and verify systems for the best diagnostic quality images at the lowest practical radiation exposure to the patient. Several manufacturers have fielded commercial systems for performance verification, but long term data indicating trends and action limits is rare. Sources of definitive information on practical clinical methods are also scarce in the scientific literature. This has led to the current situation where clinical imaging operations are routinely conducted using systems that are not optimized. The good news is that methods in common practice for conventional radiography can be applied with modification to digital radiography. Some of these methods are described in recent literature. The AAPM has recognized the dilemma and has initiated an effort to provide practical guidance to clinical physicists, i.e. Task Group 150. This lecture will discuss some components of a QA program for DR, including adaptation of conventional QA processes. The lecture will discuss methods of evaluating system performance and provide examples of potential interferences. The lecture will review commercial devices for performance evaluation and their limitations. Finally, some ongoing standardization efforts will be described. Educational Objectives: 1. Review components of a QA program and show how they apply to DR. 2. Understand how some conventional tests should be modified for a digital radiographic system integrated into an electronic image management system. 3. Identify key references and standards that can be useful in QA of DR.
Forces on a small grain in the nonlinear plasma wake of another.

The transverse force on a spherical charged grain lying in the plasma wake of another grain is analyzed to assess the importance of ion-drag perturbation, in addition to the wake-potential-gradient. The ion-drag perturbation is intrinsically one order smaller than the wake-potential force in the ratio of grain size (${r}_{p}$) to Debye length (${\ensuremath{\lambda}}_{\mathrm{De}}$). So ion-drag perturbation is important only in nonlinear wakes. Rigorous particle-in-cell calculations of the force are performed in the nonlinear regime with two interacting grains. It is found that even for quite large grains, ${r}_{p}/{\ensuremath{\lambda}}_{\mathrm{De}}=0.1$, the force is dominated by the wake-potential gradient. The wake-potential structure can then help explain the preferred alignment of floating dust grains.
A comparison of chi-squared statistics for testing homogeneity of survey data:High School and Beyond survey

The performance of several test statistics for comparing vectors of propor tions from certain survey data was compared. The statistics were used to analyze a subsample of data from the ‘High School and Beyond’ survey. These tests include the Wald test statistic X2w and the modified Wald test statistic FW, the chi-squared test statistic X2rSB and its modification FRSB, a test X2dmb based on a probability model, and a method of moments approach, X2H. Data were also simulated based on two-stage cluster sampling design and the type I error level, and the power of these tests was obtained for selected combinations of parameter values. The statistics X2DMB XRSB, FRSB and X2H performed well both for a small number of clusters or a small number of units within clusters. The power performance of these tests is quite stable. Approximate intervals were constructed for design effect constants. Methods of estimating these constants based on a normality assumption worked best.
Ultrafine NiFe2O4 powder fabricated from reverse microemulsion process

NiFe2O4 ultrafine powder with high crystallinity has been prepared through a reverse microemulsion route. The composition in starting solution was optimized, and the resulting NiFe2O4 was formed at temperature of around 550–600 °C, which is much lower than that observed from the solid-state reaction. Magnetic investigation indicates that samples are soft-magnetic materials with low coercivity and with the saturation magnetization close to the bulk value of Ni ferrite.
A derivation of the discrete-time Anderson–May model for periodic diseases

We discuss the basic properties of the Anderson–May discrete-time model and its various modifications by Mickens. We then show that this model corresponds to the discretization of a pair of coupled first-order differential equations for which the step-size is selected to be the inverse of the transition rate out of the diseased population.
Structural study of Na2O–FeO–Fe2O3–P2O5 glasses by high-pressure liquid chromatography

Three series of Na2O–FeO–Fe2O3–P2O5 glasses with compositional ranges of 3.25 < O/P < 3.5 and 0 < Fe/P < 0.67 were prepared. Glass structure was studied using high-pressure liquid chromatography (HPLC). The average chain-length of phosphate anions decreases with increasing O/P ratios and glasses with similar O/P ratios and greater Fe/P ratios have wider distributions of phosphate anion lengths due to disproportionation reactions in the glass melts.
A proton spin–lattice relaxation rate and nuclear Overhauser effect investigation of the stereochemistry of some 1‐aryl derivatives of 1,2‐dihydro‐s‐triazines

Proton spin–lattice relaxation rates (R1 values) have been measured, at 400 MHz, for a number of 2-methyl- and 2,2-dimethyl-substituted 4,6-diamino-1-aryl-1,2-dihydro-S-triazines. These compounds have high barriers to internal rotation about the aryl CN bond, and exist in solution as mixtures of enantiomeric or diastereomeric rotational isomers. Diastereotopically related 2-methyl groups in enantiomeric rotamers, and 2-methyl and 2-methine protons in diastereomeric rotamers, typically have different relaxation rates. In favourable circumstances this information may be used to identify the individual rotamers. Unequivocal direct identification of rotamers may be obtained from nuclear Overhauser effect difference spectra.
Problems in emergency planning

Abstract Emergency planning is directed at events of periodic rather than routine occurrence. The paper focuses on three major problems in emergency planning: 1. (i) Most planning is directed at specific agent-caused effects. This focus diverts attention away from more generalized principles of planning that cut through all types of emergencies. This focus also emphasizes agent uniqueness rather than the similarity of consequences which can be produced by quite diverse agents. A series of generalized principles is presented. 2. (ii) Most planning is segmented and is often restricted to those segments of the society most directly affected. Such segmentation is the cause of later lack of coordination. An argument is presented that the effective planning unit is one of larger scope, the local community system. 3. (iii) Most planning is oriented to create artificial, and thus irrelevant social structures and to impose those on others. Such a model insures its failure. A critique is made of the dominant emergency model, one of command and control, and an alternative is suggested, an emergent human resources model. That model is based on the idea of the importance of the continuity of behavior, individually and organizationally. In sum, the notion of emergency refers to the disruption of social systems, rather than to physical and material damage or disruption. Consequently, such planning needs to be rooted in research and knowledge drawn from the social sciences.
Cyclic AMP Inhibition of Thrombin-induced Growth in Vascular Smooth Muscle Cells Correlates with Decreased JNK1 Activity and c-Jun Expression

Thrombin is a potent modulator of vascular tone and vascular smooth muscle cell (VSMC) mitogenesis. Early studies from other laboratories demonstrated that cyclic AMP (cAMP) antagonizes the mitogenic effects of platelet-derived growth factor and epidermal growth factor by inhibiting the extracellular signal-regulated protein kinases (ERKs; p42, p44) group of mitogen-activated protein kinases (MAPKs) in several cell types. This report examines the role of ERKs and Jun N-terminal kinase 1 (JNK1) groups of mitogen-activated protein kinases in thrombin-induced DNA synthesis in VSMCs using agents such as forskolin and dibutyrylcyclic AMP that increase intracellular cAMP levels. Both agents significantly inhibited thrombin-stimulated DNA synthesis in VSMCs. These agents, however, had no effect on thrombin induction of ERKs activation and c-Fos expression, suggesting divergence of the latter two events from the growth-signaling events of thrombin that are sensitive to inhibition by cAMP. Thrombin activated JNK1 and induced c-Jun expression in VSMCs in a time-dependent manner. In contrast to ERKs and c-Fos, thrombin-induced JNK1 activation and c-Jun expression were sensitive to inhibition by forskolin, suggesting an association of these events with thrombin-stimulated growth in these cells. Thrombin also increased AP-1 activity, and this response was significantly blunted by forskolin. Together, these results demonstrate a correlation between JNK1 activation and c-Jun expression by thrombin and their association with the mitogenic signaling events of thrombin in VSMCs.
Five-year science outlook

Research on water quality, on solar activity's possible link to earth climate, and on potential resource deposits will be among the top scientific and technological problems to be tackled during the next 5 years, according to a National Research Council (NRC) report, ‘Outlook for Science and Technology: The Next Five Years.’ Written and reviewed by more than 200 scientists, the report is the second in a series describing current research trends; the first report was issued in 1979. The NRC report also offers a concise overview and comparison of the research environments in the United States, the Federal Republic of Germany, the United Kingdom, and France. In addition, the report identifies prospects for new technologies in seven fields with emerging technologies or emerging situations that rely heavily on technology. The fields discussed are recombinant DNA, superconductivity, medical technology, energy storage, potential new resource deposits, the space shuttle and the space telescope, and information processing.
Low Rate of Response to Enhanced Inactivated Polio Vaccine in Preterm Infants with Chronic Illness

AbstractTo study whether chronically ill, preterm infants have an adequate antibody response to enhanced inactivated polio vaccine (e-IPV), we randomly assigned seventeen preterm infants, who were hospitalized at two months of age, to receive either e-IPV, at two and four months of age, or oral polio vaccine (OPV) upon discharge from the hospital and two months later. Antibody to polio virus was measured on the days when the first and second doses of vaccine were given and two months after the second dose. Among 13 subjects from whom three sets of serologic titers were obtained, one of five immunized with e-IPV had titers ≤ 8 to all three subtypes of polio virus, whereas seven of eight immunized with OPV had titers ≤ 8 to all three subtypes (P=0.03 by Fisher's exact test). Thus chronically ill preterm infants cannot be assured of immunity to polio virus after vaccination with e-IPV at two and four months of age.
Recruitment and retention results for a population-based cervical cancer biobehavioral clinical trial.

Abstract Objective. Minority and low-income cancer patients are underrepresented in clinical trials, contributing to diminished access to state-of-the-art care and disparities in cancer outcomes including survivorship issues. In cervical cancer, there is a disproportionate disease burden among minority and underserved women and persistent quality of life disruption. We encountered significant challenges in both recruitment and retention in a randomized biobehavioral clinical trial for cervical cancer survivors, identified through California Cancer Registries, leading to this investigation. Methods. To determine differential rates of accrual and retention, data from our trial are analyzed using descriptive statistics, logistic regression and multivariate analysis of variance. Ethnic differences in associations between covariables and attrition rates were tested by interaction factors. Process evaluation and focus group data were obtained to inform improvement strategies. Results. Of eligible subjects with viable phone numbers, 29% enrolled and 71% actively or passively refused. Enrolled Hispanic women were more likely to have less education ( p p =0.003), and more children ( p =0.028). The dropout rate was associated with less education ( p =0.012), foreign-birth ( p =0.061), speaking Spanish in the home ( p =0.012). Reported reasons for active refusal were ‘too busy' for all women, ‘too emotional' for non-Hispanic women, ‘too ill' and phlebotomy for Hispanic women. Subsequent focus groups identified specific strategies to improve study materials. Conclusion. Although population-based recruitment of minority and underserved cancer patients continues to be a challenge, specific sociodemographic and disease variables can predict accrual difficulties. The information herein, taken together with disease and culturally relevant strategies, can be useful when recruiting underserved cancer survivors.
Comparative analysis of scintillation characteristics derived from different emission mechanisms in BaCl2

Crack-free La3+-substituted BaCl2 single crystals without and with Eu2+ as an activator were successfully grown using the micro-pulling-down method. Luminescence bands from BaCl2 without and with the Eu2+ activator were assigned as mainly intrinsic and extrinsic, respectively. Therefore, BaCl2 as a host material is suitable for investigating the effects of the emission mechanism on the non-proportionality curves and energy resolution plots. First, the scintillation characteristics of BaCl2:La3+(11 at. %) and BaCl2:La3+(7.7 at. %):Eu2+(0.5 at. %) single crystals were determined along with those of BaCl2 and BaCl2:Eu2+(0.5 at. %) crystals. Second, the non-proportionality curves from the different emission origins in BaCl2 were confirmed to be consistent with phenomenological models. Third, the non-proportionality curves and energy resolution plots originating from intrinsic (without Eu2+) and extrinsic (with Eu2+) luminescence were compared. The results experimentally demonstrated that the emission mechanis...
Achieving endoscopic competency in a general surgery residency

Abstract Background In 2006, the Residency Review Committee for Surgery increased the total number of required endoscopy cases for graduating residents. Our goal was to evaluate general surgery resident competency in endoscopy, focusing on quality measures. Methods A 9-year retrospective review was conducted of 29 residents. Total number of endoscopies performed throughout residency was recorded. Procedures performed as fifth-year residents with indirect supervision were evaluated for quality measures. Results An average of 76 esophagogastroduodenoscopies and 147 colonoscopies were performed through their first 4 years of residency. Chief residents performed an average of 16 esophagogastroduodenoscopies and 22 colonoscopies. Of colonoscopies performed during their fifth year, 191 were performed while the resident had only indirect supervision. During these cases, cecal intubation was achieved in 90.6% of cases, an average of .48 polyps were identified, and average scope withdrawal time was 13.4 ± 7.1 minutes. Conclusions Our data indicate that surgery residents achieve competency in colonoscopy before performing 140 colonoscopies, supporting the concept that surgery residencies can function as an excellent training ground for endoscopy.
ALPHA-ALPHA SCATTERING FROM 12.88 TO 21.62 MEV

The differential scattering cross section of alpha particles on helium has been investigated as a function of energy in the range from 12.88 to 21.62 Mev. The data obtained indicate a very strong angular dependence. This further appears to be a fairly sensitive function of energy. At the lower excitations there is a rather singular interference between the Coulomb and nuclear interactions. Above 20 Mev, interferences among the various components of the nuclear phase shifts again give rise to marked singularities. These data have been analyzed with respect to the phase shifts arising from the angular momentum components of the interaction. This decomposition indicated resonances at 7.55 and 10.8 Mev with widths, $\ensuremath{\Gamma}$ of 1.2 Mev in each case and state assignments of 0 and 4, respectively.
Recovery in Context: Bereavement, Culture, and the Transformation of the Therapeutic Self

The concept of recovery is integral to the work of bereavement professionals, though there remains considerable debate as to the precise definition and applicability of the term. A number of factors have contributed to the controversy; competing bereavement models, for instance, have given rise to fundamental differences in the way that recovery is conceptualized, whereas an epistemological divide between researchers and practitioners has further hindered theorists' efforts to arrive at a definition with far-ranging explanatory power. An examination of fundamental concepts from bereavement literature, resilience research, and existential philosophy may be helpful toward the development of a recovery concept that encompasses an array of thanatological perspectives. An educational model emphasizing the phenomenological dimensions of learning addresses the crucial relevance of culture to bereavement, and helps account for the self-transformation inherent in a range of grief experiences.
Improved Stakeholder Management: The Key Revitalizing the HMO Movement?:

In summary, our purpose has been to propose and to demonstrate that the survival of HMOs (in whatever form) depends on the proper identification and management of key stakeholder strategies. It is believed that identification and assessment of key stakeholders holds much promise for improving both HMO management and the future performance of HMOs.
A longitudinal examination of emotion regulation: pathways to anxiety and depressive symptoms in urban minority youth.

Background: Difficulty regulating emotions is a symptom of many psychological disorders yet little research has examined the longitudinal relations of particular facets of emotion regulation (ER) that may differentiate between internalizing symptoms. Method: At-risk youth (n = 102; 44.1% boys, 77.5% Black; Mage = 9.65) and caregivers (n = 74; 87.1% mothers) participated in a 2-year longitudinal study. Children reported on their ER, and children and caregivers on symptomatology. Results: Different patterns, varying by emotion facet (dysregulation, inhibition, coping) and type (anger, sadness, worry), predicted anxiety and depression symptoms. Conclusions: Anxiety and depression are entities with distinct patterns of emotion-related antecedents. Key Practitioner Points  The findings from this study can inform prevention and intervention programs because they provide evidence for the need to consider children’s discrete emotional experiences and the contexts in which they may struggle to regulate their anger, sadness, and worry.  Prevention programs may consider specifically targeting children’s suppression as well as under-controlled methods of coping with negative emotion in their emotion skill-building units.  These findings can provide support for the few treatment programs for childhood anxiety and depression that have incorporated an affective module or component to their cognitive behavioral treatment for children and adolescents.  Proactively facilitating the development of high-risk children’s ER skills at key junctures in early childhood may result in more successful psychological adjustment.
Gravity and the cells of gravity receptors in mammals

Two new findings, that crystals located in the inner ear gravity receptors of mammals have the internal organization requisite for the piezoelectric property, and that sensory hair cells of these same receptors possess contractile-appearing striated organelles, have prompted the author to model mammalian gravity receptors in the ear on the principles of piezoelectricity and bioenergetics. This model is presented and a brief discussion of its implications for the possible effects of weightlessness follows.
Optimal decentralized control problem as a rank-constrained optimization

This paper is concerned with the long-standing optimal decentralized control (ODC) problem. The objective is to design a fixed-order decentralized controller for a discrete-time system to minimize a given finite-time cost function subject to norm constraints on the input and output of the system. We cast this NP-hard problem as a quadratically-constrained quadratic program, and then reformulate it as a rank-constrained optimization. The reformulated problem is a semidefinite program (SDP) after removing its rank-1 constraint. Whenever the SDP relaxation has a rank-1 solution, a globally optimal decentralized controller can be recovered from this solution. This paper studies the rank of the minimum-rank solution of the SDP relaxation since this number may provide rich information about the level of the approximation needed to make the ODC problem tractable. Using our recently developed notion of “nonlinear optimization over graph”, we propose a methodology to compute the rank of the minimum-rank solution of the SDP relaxation. In particular, we show that in the case where the unknown decentralized controller being sought needs to be static with a diagonal matrix gain, this rank is upper bounded by 4. Since the upper bound is close to 1 and does not depend on the order of the system, the ODC problem may not be as hard as it is thought to be. This paper also proposes a penalized SDP relaxation to heuristically enforce the few unwanted nonzero eigenvalues of the solution to diminish.
Will the AECC's course delivery recommendations work in the introductory accounting course? Some preliminary evidence

Abstract Accounting pedagogy is currently undergoing drastic changes. Combined with the AICPA's 150-hour requirement and the AACSB's new accreditation requirements, the AECC's recommendations for changes in accounting education are redefining what educators do in the classroom. In Position Statement No. 1 “Objectives of Education for Accountants,” the AECC targeted several characteristics of the current accounting education experience for change. These recommendations address both content and delivery issues and are consistent with recommendations made by the AICPA and the AACSB. However, in spite of the strength of the arguments put forth in favor of the AECC's recommendations, one question remains: Will implementation of the AECC's recommendations result in real, positive, measurable changes in the accounting education experience? In this paper, we examined the combined effect of several of the delivery recommendations made in Position Statement No. 1 by comparing the degree to which specific teaching objectives were achieved using a traditional accounting practice set (which did not reflect the AECC's delivery recommendations) versus a business simulation accounting practice set (which did reflect the AECC's delivery recommendations). The results indicate that, with respect to the specific educational experience tested, implementation of selected AECC recommendations will result in positive enhancement of the accounting education experience.
Photodamage to the lens in vitro: implications of the Haber-Weiss reaction.

Abstract Studies have been conducted to examine the implications of photochemical of O2− and its derivatization to H2O2 and OH· in the physiology of the lens in vitro. Physiological status was determined by measuring the uptake of rubidium by the intact tissue when cultured in riboflavin-containing medium, in dark and light, and in the presence and absence of various scanvengers. In the presence of light, the uptake of rubidium in the lens was greatly diminished; this suggests photodamage to the tissue. MnSOD and ferricyanide protected against this photochemical damage. The damaging process was thus initiated by the generation of O2−. The tissue damage was also attenuated by catalase, ferrocyanide, and mannitol. These results, therefore, suggest the participation of hydrogen peroxide and the subsequent Haber-Weiss reaction in the photodamaging process.
Synthesis and electrochemistry of alkyl ring-substituted polyanilines

Polymerisation electrochimique de l'aniline sur une electrode d'or ou de platine dans une solution d'acide chlorhydrique
An improved method of establishing human fibroblast cultures from explants

A method of using cover slips in establishing human fibroblast cultures from explants is described. This procedure has three important advantages. Firstly, the cover slips with cells may be removed from the explants and transferred without the use of trypsin. Secondly, cells grow out from the explants within 48 hours and ready to be transferred within two weeks. Thirdly, it eliminates the problems of detachment of the explants from culture dishes.
Ecological and evolutionary implications of diet in monitor lizards

A survey of 35 species indicates that monitor lizards (Varanus) typically hunt over large areas, search in particular microhabitats, and feed frequently on a wide variety of prey, many of which are relatively small. There is ontogenetic, seasonal, and geographic variation in diet. With some exceptions, invertebrates are the predominant prey, but rare predation on vertebrates is often energetically significant. A few monitors specialize on prey types that occur as occasional items in the diet of species with more generalized diets; these include crabs, snails, orthopterans, lizards, and large mammals. For most species, prey specialization occurs via habitat selection and a variety of prey types and sizes are eaten, as expected for widely searching predators. Comparisons with other anguimorphans suggest that derived features of Varanus are associated with high body temperature and activity levels; specialized chemoreception; and rapid, skillful capture of hidden and/or potentially hard to catch prey. Occasional ingestion of moderately large prey is primitive for Varanoidca (Helodermatidae +Varanidae), accentuating a trend that is perhaps primitive for anguimorphan lizards. Reduction of very large prey prior to ingestion is a derived attribute within Varanus, seen infrequently in several larger species and commonly in V. komodoensis. This study illustrates the synthesis of comparative natural history in a phylogenetic context, a method that addresses the history of organismal change.
Catalytic hydrothermal hydrodenitrogenation of pyridine

Abstract We herein report on the hydrothermal catalytic conversion of pyridine to hydrocarbons. The catalytic activity of several supported noble metal (5 wt%) catalysts (Pt/C, Pd/C, Ru/C and Rh/C, sulfided Pt/C, and Pt/γ-Al2O3), a traditional hydrodenitrogenation (HDN) catalyst (sulfided CoMo/γ-Al2O3), a transition metal carbide (Mo2C) and sulfide (MoS2), and a noble metal oxide (PtO2) toward the HDN of pyridine in a hydrothermal reaction medium between 250 and 400 °C was determined. The Pt/γ-Al2O3 catalyst proved to be the most active for hydrothermal HDN of pyridine, and we report the effects of batch holding time, reaction temperature, catalyst loading, initial hydrogen pressure, and water density on the Pt/γ-Al2O3-catalyzed HDN of pyridine in supercritical water. The latter two process variables had the greatest influence on the product yields and distribution. Conditions were identified that lead to essentially 100% conversion of pyridine to N-free hydrocarbons. The catalyst shows some modest loss in activity upon being reused. An HDN reaction network for pyridine under hydrothermal conditions was proposed. The main HDN products are n-butane and n-pentane. Nitrogen was removed as ammonia.
The Necessary Revolution: Sex-Positive Feminism in the Post-Barnard Era

In this interview sexologist and author Carol Queen discusses feminist and queer sexual politics in the pre and post Barnard eras. Despite the policing of sexual desires and practices during the height of the feminist sex wars, Queen argues that sex-positive feminists and sex radicals were able to create alternative spaces, resources, and counter-discourses that had tangible effects on many people's sexual lives and identities.
Ultrastructure of lower Paleozoic dyads from southern Ohio II: Dyadospora murusattenuata, functional and evolutionary considerations

Abstract Fossil cryptospore dyads consistent with published descriptions of Dyadospora murusattenuata fall into two general categories when examined with the TEM. Type I dyads are enclosed, and have a wall consisting of (1) an outer homogeneous layer that is present on non-contact surfaces, but absent in large part over the contact surface, (2) a middle layer composed of plate-shaped units, and (3) an innermost granular layer. The latter two layers are continuous over each of the dyad members. Type II dyads show a range of ultrastructural types, differing primarily with respect to the extent of a region of spongy wall material that occurs at the edge of the contact face. Thin regions and breaks present in the walls of many dyads and pseudodyads may represent primitive sutures. Ultrastructural analysis suggests the existence of at least two separate lineages of plants in the Late Ordovician and Early Silurian, but the phylogenetic relationship between these groups and to more recent land plants remains uncertain.
70 REFREEZING POST-THAWED GOAT SEMEN

The ability to successfully refreeze caprine sperm could provide a means of salvaging semen that was mistakenly thawed. The objective of this study was to compare treatment post-thaw semen parameters of twice-frozen caprine semen. Frozen semen from six mature Boer bucks (range in age from 2 to 6 years) was utilised for this experiment. Semen from each buck was extended in an egg yolk-based extender and packaged in 0.5-mL plastic straws before freezing and stored in liquid nitrogen. Three units of frozen semen from each buck was randomly allotted to each of four treatments as follows: (A) thaw and evaluate (control), (B) thaw, then plunge into liquid nitrogen, thaw, and evaluate, (C) thaw, incubate for 3 min at 37°C, slow cool and freeze, thaw, and evaluate, and (D) thaw, incubate for 5 min at 37°C, slow cool and freeze, thaw, and evaluate. Post-thaw parameters included total motility (TM), progressive motility (PM), membrane integrity (MI), and sperm abnormalities (AB). To obtain MI and AB, samples were stained with an eosin-nigrosin stain. A computerized programmable freezer was used to refreeze semen samples in treatment (Trt) C and Trt D. During the slow cooling portion of the protocol, samples were allowed to equilibrate at 38°C, then cooled to 4°C at a rate of 0.30°C min–1, and then held for 5 min. Samples were then cooled to –8°C at a rate of 15°C min–1, seeded, and cooled to –10°C at 15°C min–1, samples were then ramped to –80°C at 30°C min–1 before plunging into liquid nitrogen. Results indicate that post-thaw TM was significantly greater for Trt A (60%) when compared with Trt B, C, and D (0.05, 35, and 39%, respectively). Mean TM were not different between Trt C (35%) and Trt D (39%) but were greater than that for Trt B (0.05%). The PM for post-thaw semen in Trt A was also significantly greater (P < 0.05) when compared with that for Trt B and C (0.05 and 25%); however, no difference was found for mean PM for Trt A (47%) and Trt D (30%), nor were differences found between Trt C (25%) or Trt D (30%). Membrane integrity was higher in Trt A (27%) when compared to Trt B (2.2%). No differences in membrane integrity where found between Trt A, C, and D (27, 13, and 14%, respectively). Additionally, no differences were found between Trt B, C, and D for membrane integrity. Sperm morphology were not different were found with across all treatment groups. These results (i.e. Trt C and D) indicate that semen from mature Boer bucks can undergo a second freeze thaw cycle and still retain motility without dramatically affecting sperm morphology and membrane integrity. These findings indicate that directly plunging recently thawed semen back into liquid nitrogen should not be used for artificial insemination.
One- and two-locus models of the origin of worker behavior in hymenoptera

Abstract Hamilton, 1964 , Hamilton, 1972 suggested that, if females are singly inseminated, the asymmetries in intra-familial relationships inherent in haplo-diploidy should predispose the Hymenoptera to evolve female sex-limited worker behavior, if either a worker raises sibs as reproductives but raises a bias of sisters (pathway 1), or she raises a combination of sibs and sons as reproductives but substitutes sons for brothers preferentially (pathway 2). To investigate these hypotheses when mating is random, we present mathematical and numerical analyses of the one-locus two-allele model of Charnov (1978a) which we generalize. Furthermore, we extend the Charnov model to a more realistic two-locus situation where we postulate that the ability of a worker to raise a bias of sisters or to substitute sons for brothers preferentially is controlled by a locus separate from the locus controlling worker behavior, rather than being a pleiotropic effect of that locus. Considerations of the relative stringencies of the conditions for substitution of the allele for worker behavior and the constraints on linkage suggest that pathway 2 is more likely than pathway 1 for the origin of worker behavior. For pathway 1, we compare the Charnov model with its diplo-diploid analogue. This comparison reveals that, depending on the penetrance of the allele for worker behavior in the heterozygous state, both models permit the evolution of worker behavior even when workers raise the ratio of sisters to brothers laid by the queens, and that an advantage to haplo-diploidy becomes apparent only when workers raise a bias of sisters. For pathway 1, we also consider a generalization of the Craig model (Craig, 1979) which is quite similar to the Charnov model.
Yield, Protein Content, and Viscosity of Starch from Wet-Milled Corn Hybrids as Influenced by Environmentally Induced Changes in Test Weight

ABSTRACT Forty-three yellow dent corn samples of five different hybrids varying in test weight and moisture content were obtained from 14 different locations in 1993. The locations for acquired samples were selected randomly to cover a wide range of test weights based on preliminary data from eight states of the corn belt where 94% of the U.S. corn crop was produced in 1993. Samples were wet-milled using a 100-g standard laboratory-scale wet-milling procedure. Protein content in starch and starch viscosity were determined. Starch yield, protein content in starch, and starch viscosity were not affected significantly by test weight.
Antibiotic susceptibility patterns of ocular bacterial flora in patients undergoing intravitreal injections.

Purpose To determine the antibiotic susceptibility patterns of conjunctival flora in patients undergoing intravitreal (IVT) injection. Design Prospective, observational study. Participants Patients (n = 85) scheduled to undergo 136 IVT injections at California Vitreoretinal Center at Stanford University. Methods Conjunctival cultures were obtained on the day of the IVT injection from the injection site bulbar conjunctiva before the application of povidone-iodine or antibiotics. Main Outcome Measures Bacterial isolates were identified and tested for antibiotic susceptibility using either the Kirby-Bauer disc-diffusion technique or MicroScan-WalkAway system. Results Our analysis included 136 samples collected from 90 eyes of 85 patients. Of those with positive cultures (n = 65), the most common bacterial isolates were coagulase-negative staphylococci (CNS), comprising 59 (83%) of the 71 bacterial strains. Among the CNS, all were susceptible to vancomycin and >80% were susceptible to gentamicin, chloramphenicol, tetracycline, and imipenem. Between 60% and 80% of the CNS were susceptible to the cephalosporins and newer generation fluoroquinolones. Fewer than 60% were susceptible to the penicillin analogs, erythromycin, and the earlier generation fluoroquinolones. Nearly half of the CNS (47%) were resistant to oxacillin/methicillin. Conclusions Bacteria isolated from the injection site of patients undergoing IVT injections were mostly CNS. Most are sensitive to vancomycin, gentamicin, and chloramphenicol. Financial Disclosure(s) Proprietary or commercial disclosure may be found after the references.
Influences of dynamic level and pitch register on the vibrato rates and widths of violin and viola players

The purpose of this study was to investigate possible influences of pitch register and dynamic level on vibrato rates and widths of university and high school violin and viola players. Analysis showed that pitch register significantly affected the vibrato rates and widths of the performers. Musicians vibrated 0.32 Hz faster and approximately 26 cents wider during high pitches than during low pitches. Dynamic level also significantly affected vibrato width. Performers increased vibrato width approximately 4 cents in the forte passages when compared to the piano passages. Furthermore, violinists demonstrated a tendency to vibrate slightly faster and wider than violists, and university performers varied their vibrato width to a greater extent between the piano and forte passages than did the high school performers. These results, along with further study, can contribute to the development of a systematic method for teaching vibrato.
Aerodynamic side force induced by nozzle entrance flow asymmetry

Abstract : The Star 48 upper stage rocket motor and payload system appears to precess in a coning motion which affects the flight path. The coning motion has been attributed to side forces generated because of deviations of the rocket nozzle entrance flow from truly axisymmetric conditions. In this report, an experimental investigation is described in which intentional nozzle entrance flow misalignment was produced and consequent side force was measured on a model at a simulated altitude of 170,000 ft. Side forces generated with an approximately 1/50th scale Star 48 rocket nozzle were quite small when compared to the predictions and measurements of previous investigators, but the difference was attributed to the difference where the flow inclination or misalignment occurs. When the flow is inclined at the nozzle throat, the downstream effect of the inclination is predictably large. When the flow is inclined in the plenum upstream of the nozzle entrance, the downstream effect is smaller by an order of magnitude. The observed side forces show a dependence on the nozzle length, as indicated by earlier investigators. Keywords: Rocket nozzles; Nozzle gas flow; Liquid propellant rockets; Rocket nozzles.
Detection of structural and functional changes in biological materials using angle-resolved low coherence interferometry

A well-established method of assessing structure is inverse light scattering analysis. With inverse light scattering analysis, the measured scattering properties of a scatterer(s) are associated with the most probable scattering distribution predicted by an appropriate light scattering model. One commonly used light scattering model is Mie theory, the electromagnetic theory of spherical scattering. Although Mie theory is a spherical scattering model, it has been used for deducing the geometry of spheroidal scatterers, which are important for studies of biological cell structure. The angle-resolved low coherence interferometry (a/LCI) technique is one method of Mie theory – based inverse light scattering analysis that has been used to evaluate biological structure both ex vivo and in vitro. In the present study, we examine the ability of a/LCI to assess structure, geometry, and cellular organization in ways that will further enable the study of function in biological materials.
Loss and in situ production of perfluoroalkyl chemicals in outdoor biosolids–soil mesocosms

Abstract An outdoor mesocosm study was conducted in Baltimore, Maryland, to explore the fate of thirteen perfluoroalkyl substances (PFASs) over the course of three years in biosolids/soil mixtures (1:2) exposed to ambient outdoor conditions. Analysis by liquid chromatography tandem mass spectrometry showed perfluorooctanoate (PFOA) to be the most abundant analyte found early in the soil weathering experiment at 24.1 ng/g dry weight (dw), followed by perfluoroundecanoate (PFUnDA) and perfluorodecanoate (PFDA) at 18.4 and 17.4 ng/g dw, respectively. Short-chain perfluorinated carboxylates (PFCAs; C 4 –C 8 ) showed observable loss from biosolids/soil mixtures, with experimentally determined first-order half-lives in soil ranging from 385 to 866 days. Perfluorooctane sulfonate (PFOS), perfluorononaoate (PFNA) and PFUnDA levels in biosolids/soil mixtures remained stable, while other long-chain PFCAs [PFDA, perfluorododecanoate (PFDoDA)] and perfluorooctane sulfonamide (PFOSA) levels increased over time, presumably due to the breakdown of unidentified precursors in a process analogous to that reported previously for wastewater treatment plants. This study informs risk assessment initiatives by furnishing data on the environmental persistence of PFASs while also constituting the first report on in situ production of long-chained PFASs in terrestrial environments.
Validation of Strengths and Limitations of Seismic Methods in Quality Management and Assessment of Shotcrete Liners

Shotcrete liners are being utilized more frequently in transportation infrastructure as retaining structures and tunnel covers. Despite their economic advantages to concrete, the initial quality of construction and long-term durability of shotcrete liners are of concern among highway agencies. The quantitative construction quality management is needed to ensure adequacy and uniformity of strength and thickness. Also, periodic inspection of shotcrete liners is necessary to assess possible material deterioration and to detect the onset of defects. The impact echo and ultrasonic surface wave methods are two nondestructive sonic methods that have been proven effective for those purposes in concrete structures. Unlike concrete slabs, shotcrete slabs exhibit spatial heterogeneity. In addition to heterogeneity, surface roughness of shotcrete adds some complications into data interpretation in terms of thickness measurement. The practical effectiveness of applying these methods to shotcrete liners using a commercially-available nondestructive testing device was evaluated in three actual tunnels. This paper focuses on validating the effectiveness of these methods through a well-controlled testing on a number of shotcrete specimens constructed with and without known defects. Results from this study demonstrate that the stiffness of shotcrete layer and the presence of delamination and voids within the shotcrete liners can be detected well by using these seismic methods in combination.