cssi/SciSciGPT-SciSciNet huggingface dataset:
Mitigation of Energy Emanating from Imploding Metallic and Composite Underwater Structures

An experimental study was conducted to investigate the energy mitigation of hydrostatically initiated implosions of composite and metallic structures. Energy mitigation is achieved by placing polyurea coatings of different thicknesses at different locations onto imploding structures. The implodable structures are made of AL 6061-T6 and carbon-fiber/epoxy composite tubes with seven layers of unidirectional carbon fabric reinforcement arranged in a [±15/0/±45/±15] layup. The implodable specimens are sealed from the water with end caps and suspended inside a large pressure vessel that simulates a free-field marine environment. The hydrostatic pressure inside the pressure vessel was gradually increased until the specimens became unstable and collapsed. The collapse velocities and localized pressures of the imploding structures were captured during the experiments. Two high-speed cameras recorded the implosion phenomenon while dynamic pressure transducers measured the emitted pressure pulses. The results of these experiments show that polyurea can strongly reduce the pressure pulses emitted during the implosion; in turn, mitigating the emanating implosion energy. Moreover, the overall increase in performance, regarding energy reduction, is due to the polyurea coating and not the higher mass of the implodable structures. Placing polyurea coatings in the interior of the implodable structure leads to a higher performance regarding mitigating released energy than exterior placed coatings. Lastly, considerable increase in exterior coating volumes may result in adverse effects such as increasing structural velocity and energy emitted.
The Commonwealth Impresario

A perfect historical context and illustration of postcolonialism, and of postcolonial theory of literary production in Africa as sites of overlapping mediations, presents itself in its intensity and contradictions in a little known memory of the saga of Bernth Lindfors working to preserve the manuscripts of Amos Tutuola. The contestations that expressed themselves in the Lindfors’ Nigeria experience could be said to have crystallized ultimately in what is famously known as the Arusha Accord: a gathering where African writers and publishers contracted a memorandum of understanding to guide their mutual enterprise. The “Accord,” unusual though it sounds, echoes the proxy wars and treaties of empire in which, ironically, local publishers were now ceded to the frontlines as if they were the last men warring against those “taking possession” ala Joseph Conrad. I approach this chapter by taking Lindfors’ particular episode as the first in a series of proxy struggles in which the Commonwealth and the nation set the beginning stages over the struggle for control of the production of culture. A discussion of the archive enables “some pertinent discussion of the politics of various kinds of modern repository” that includes museums and publishers’ repositories. These repositories are symbols and vehicles of power, the control of which animates the struggle over cultural production. The travails of international scholarship enable us to segue into the complicated legacies of international publishing, its contexts, and genealogies. It is precisely to make possible such analytical correlation and transition, and to capture the practice of commonwealth in the production of culture, that I have advisedly chosen the term impresario over publisher in the title of this chapter. The chapter is thus an engagement, behind and beyond the veil of aesthetic form, with the sweeping macro-, socio-cultural and literary developments that subsequent chapters take on at the micro-, stylistic, level of textual analysis and close reading.
Visualization and Analysis of Brain Function Using Multi-Modality Image Integration

Multi-modality image integration, in which functional positron emission tomography (PET) and single-photon emission computed tomography (SPECT) images are co-registered spatially with structural x-ray computed tomography (CT) and magnetic resonance (MR) images, can provide new knowledge of correlates of brain function and brain structure that was difficult to access previously. For visualization and analysis of brain function, we have used this concept in the following areas: (1) Image reconstruction: We have developed a Bayesian data augmentation method that uses Gibbs prior for incorporation of high-resolution structural information extracted from the correlated CT and MR images in reconstruction of functional PET images. (2) Image segmentation and visualization: We have developed multi-spectral approaches for segmenting brain images into entities of functional/structural importance based on the integrated PET, CT, and multiple MR images. These segmented regions can be displayed in both 2-D and 3-D by using various visualization techniques. (3) Brain function mapping: Brain activation using PET has become a powerful tool for mapping brain functions in health and disease. Image subtraction techniques applied to a pair of images acquired respectively under baseline and activated conditions form the basis for detecting subtle and localized brain functions. Image integration is useful in correction for possible shifts in subject position between two separate scans, in quantitative interpolation between slices for localizing small and subtle brain functional signals, and in overlaying of the detected brain function signals with structural MR or CT images for providing accurate localization of the physiology/anatomy correlates. These image integration approaches provide improvements in reconstruction accuracy and useful new tools for visualization, as well as powerful new techniques for brain mapping. When used in combination, understanding of certain brain functions that were difficult to assess previously becomes accessible.
Lymph flow transients following elevation of venous pressure in the dog hindpaw.

Steady-state lymph flows have been measured in numerous organs (1,2,6,8,9,10,11,12) for both normal and altered filtration pressure*. The steady-state measurement of lymph flow are very useful for measuring or calculating PC, PT, ЛL and the imbalance in Starling forces across the capillary membrane (8,9); however, this type of lymph flow measurement does not yield any information as to the mechanisms responsible for lymphatic propulsion.
Role of Capsaicin-Sensitive Primary Afferent Nerves in the Neuroendocrine Copulation Reflex

Maintenance of the luteal phase and progesterone (P4 ) secretion adequate to support nidation and pregnancy or pseudopregnancy in the proestrous rat requires intact innervation of the uterine cervix [1]. Stimulation of the cervix during copulation, or by experimental means, is conveyed via neural pathways to the hypothalamus [2,3] altering the gonadotropin secretion pattern [4,2] and facilitating the secretion of prolactin (Prl), a luteotropin in the rat, by the hypothalamo-hypophyseal axis [5,6,14]. This results in cessation of estrous cyclicity and stimulation of P4 secretion by the corpus luteum [7,4,5], thus completing the neuroendocrine copulation reflex (response) [8]. Our previous results have demonstrated an extensive innervation of the uterine cervix by capsaicin- sensitive primary afferent nerves containing markers for substance P [9], and further, that groups of capsaicintreated (CAP) neonatal rats subsequently have a markedly reduced incidence of pregnancy following confirmed matings [10]. This suggested that the neural limb of the neuroendocrine copulation reflex consisted of primary afferent “c” type nerves.
Field Oriented Sliding Mode Control of Surface-Mounted Permanent Magnet AC Motors: Theory and Applications to Electrified Vehicles

Permanent magnet ac motors have been extensively utilized for adjustable-speed traction motor drives, due to their inherent advantages including higher power density, superior efficiency and reliability, more precise and rapid torque control, larger power factor, longer bearing, and insulation life-time. Without any proportional-and-integral (PI) controllers, this paper introduces novel first- and higher-order field-oriented sliding mode control schemes. Compared with the traditional PI-based vector control techniques, it is shown that the proposed field oriented sliding mode control methods improve the dynamic torque and speed response, and enhance the robustness to parameter variations, modeling uncertainties, and external load perturbations. While both first- and higher-order controllers display excellent performance, computer simulations show that the higher-order field-oriented sliding mode scheme offers better performance by reducing the chattering phenomenon, which is presented in the first-order scheme. The higher-order field-oriented sliding mode controller, based on the hierarchical use of supertwisting algorithm, is then implemented with a Texas Instruments TMS320F28335 DSP hardware platform to prototype the surface-mounted permanent magnet ac motor drive. Last, computer simulation studies demonstrate that the proposed field-oriented sliding mode control approach is able to effectively meet the speed and torque requirements of a heavy-duty electrified vehicle during the EPA urban driving schedule.
Consistency of Continuous Queries in Fog Computing

Abstract A fog computing architecture consists of edge nodes that generate and possibly pre-process (sensor) data, fog nodes that do some processing quickly and enable any actuations that may be needed, and cloud nodes that may perform further, detailed, analytics for long-term and archival purposes. The input data consist of tuples. They are processed in batches. The computation to be done on a batch is decomposed into sub-computations to be executed at the different nodes in the fog architecture. Guaranteeing consistency of the executions is very important. Consistency issues arise for sub-computations at individual nodes, the entire computations on individual batches and computations over sequences of input batches; the latter form continuous queries (CQs). CQs consist of one-time executions, called 1-CQs, and are partitioned into CQ-segments. In this paper, the sub-computations are assumed to be executed individually and serially at each node. We study global serializability of the entire computations on the batches. For CQs, we study the consistency of the CQs in terms of the sensitivity of the 1-CQs and the CQ-segments to breaks in the sequence of input batches due to some batches not being processed completely. Our study is also applicable to breaks occurring due to some actuations or external updates to the program states that affect the semantics of the input batches.
Stresses that Raise Np4A Levels Induce Protective Nucleoside Tetraphosphate Capping of Bacterial RNA.

Summary Present in all realms of life, dinucleoside tetraphosphates (Np 4 Ns) are generally considered signaling molecules. However, only a single pathway for Np 4 N signaling has been delineated in eukaryotes, and no receptor that mediates the influence of Np 4 Ns has ever been identified in bacteria. Here we show that, under disulfide stress conditions that elevate cellular Np 4 N concentrations, diverse Escherichia coli mRNAs and sRNAs acquire a cognate Np 4 cap. Purified E. coli RNA polymerase and lysyl-tRNA synthetase are both capable of adding such 5′ caps. Cap removal by either of two pyrophosphatases, ApaH or RppH, triggers rapid RNA degradation in E. coli . ApaH, the predominant decapping enzyme, functions as both a sensor and an effector of disulfide stress, which inactivates it. These findings suggest that the physiological changes attributed to elevated Np 4 N concentrations in bacteria may result from widespread Np 4 capping, leading to altered RNA stability and consequent changes in gene expression.
PARAMETER AND UNCERTAINTY ESTIMATION FOR DYNAMICAL SYSTEMS USING SURROGATE STOCHASTIC PROCESSES.

Inference on unknown quantities in dynamical systems via observational data is essential for providing meaningful insight, furnishing accurate predictions, enabling robust control, and establishing...
Pipeline Embolization Device for Treatment of Craniocervical Internal Carotid Artery Dissections: Report of 3 Cases

Background Dissecting pseudoaneurysms of the craniocervical circulation are uncommon, accounting for only 3% of all cerebral aneurysms. These aneurysms pose a challenge due to their location and anatomic configuration. The Pipeline Embolization Device (PED) is a flow diversion technique that successfully treats aneurysms by diverting blood flow away from the aneurysm and reconstructing the diseased parent artery by altering its hemodynamics. Case Description We report 3 cases in which the PED was used to treat craniocervical carotid artery dissection with associated pseudoaneurysms. A single PED was used in the first case, 4 PEDs were used in the second case, and 3 PEDs and a PRECISE PRO RX carotid stent were placed in the third case. All 3 patients achieved full neurologic recovery postoperatively. Cerebral angiography performed postoperatively demonstrated revascularization, good laminar flow, and no in-stent or adjacent stenosis. Conclusions PED placement offers a safe and effective method of treating spontaneous or traumatic craniocervical carotid artery dissections with excellent neurologic outcomes postoperatively and complete long-term aneurysmal occlusion.
Load-displacement response of drilled shaft tip in soft rocks of sedimentary origin

Abstract A database of in situ drilled shaft and plate load tests in soft rock mass is developed. Analyses of the in situ load tests suggest that (i) the development of tip contact pressures is related to the rock mass shear strength, rock mass deformation modulus, and the vertical displacement of the drilled shaft tip, (ii) embedding the drilled shaft tip contributes to the development of punching shear failure mechanism in the underlying rock mass, however, the mobilized tip contact pressures do not significantly increase as the embedment depth increases unless the rock mass shear strength and deformational properties drastically increase with embedment depth, and (iii) the drilled shaft diameter does not significantly influence the development of the contact pressures, especially in large diameter drilled shafts. A framework for the analysis of the load-displacement response of the drilled shaft tip in soft rock mass is proposed using the in situ load tests. The proposed framework accounts for the observed nonlinear load-displacement response of soft rock mass and is a function of the initial normal stiffness and the initial yield pressure of the rock mass under the drilled shaft tip. Simple equations are developed for the initial normal stiffness and the initial yield pressure of soft sedimentary rocks. Additionally, in situ and laboratory test results are used to provide recommendations for the prediction of the parameters that are required in the proposed models for the initial normal stiffness and the initial yield pressure, namely the unconfined compressive strength and deformation modulus for the rock mass.
Population-attributable fraction of risk factors for severe maternal morbidity.

Background Severe maternal morbidity is an important proxy for maternal mortality. The population-attributable fraction is the proportion of a disease that is attributable to a given risk factor and can be used to estimate the reduction in the disease that would be anticipated if a risk factor were reduced or eliminated. Objective We sought to determine the population-attributable fraction of potentially modifiable risk factors for severe maternal morbidity. Materials and Methods We used a retrospective cohort of 86,260 delivery hospitalizations from Magee-Womens Hospital, Pittsburgh, PA, for this analysis (2003−2012). Severe maternal morbidity was defined as any of the following: Centers for Disease Control and Prevention International Classification of Diseases 9th Revision diagnosis and procedure codes for the identification of maternal morbidity; prolonged postpartum length of stay (defined as >3 standard deviations beyond the mean length of stay: >3 days for vaginal deliveries and >5 days for cesarean deliveries); or maternal intensive care unit admission. We used multivariable logistic regression with generalized estimating equations to estimate the association of prepregnancy overweight or obesity, maternal age ≥35 years, preexisting hypertension, preexisting diabetes, excessive gestational weight gain, smoking, education, and marital status with severe maternal morbidity. We then calculated the population-attributable fraction for each risk factor. We also examined the impact of modest reductions and elimination of risk factors on the population-attributable fraction of severe maternal morbidity. Results The overall rate of severe maternal morbidity was 2.0%. Overweight and obesity, maternal age ≥35 years, preexisting hypertension, excessive gestational weight gain, and lack of a college degree had population-attributable fractions ranging from 4.5% to 13%. If all risk factors had been eliminated, 36% of cases could have been prevented. Modest reductions in the prevalence of excessive body mass index and advanced maternal age had minimal impact on preventing severe maternal morbidity. Smoking during pregnancy and marital status were not associated with severe maternal morbidity. Conclusion Our data suggest that maternal morbidity can be reduced by modifying common, individual-level risk factors. Nevertheless, the majority of cases were not attributable to the patient-level risk factors that we examined. These data support the need for large studies of patient-, provider-, system-, and population-level factors to identify high-impact interventions to reduce maternal morbidity.
The three-year monitoring of 18 elements in five edible mushroom species collected from an old orchard

AbstractThe content of Al, As, Be, Cd, Ca, Cr, Co, Cu, Fe, Pb, Li, Mg, Mn, Ni, Rb, Se, Sr, and Zn in fruiting bodies of edible mushrooms Calocybe gambosa, Entoloma clypeatum, Entoloma saepium, Xero...
Bariatric Surgery in Patients with Cirrhosis: Careful Patient and Surgery-Type Selection Is Key to Improving Outcomes

Previous reports suggest an increased mortality in cirrhotic patients undergoing bariatric surgery (BS). With advancements in management of BS, we aim to study the trends, outcomes, and their predictors in patients with cirrhosis undergoing BS. A retrospective study was performed using the National Database from 2008 to 2013. Outcomes of BS in patients with cirrhosis were studied. In-hospital mortality, length of stay, and cost of care were compared between patients with no cirrhosis (NC), compensated cirrhosis (CC), and decompensated cirrhosis (DC). Multivariable logistic regression analysis was performed to study the predictors of mortality. Of the 558,017 admissions of patients who underwent BS during the study period, 3086 (0.55%) had CC and 103 (0.02%) had DC. An upward trend of vertical sleeve gastrectomy (VSG) utilization was seen during the study period. On multivariate analysis, mortality in CC was comparable with those in NC (aOR 1.88; CI 0.65–5.46); however, it was higher in DC (aOR 83.8; CI 19.3–363.8). Other predictors of mortality were older age (aOR 1.06; CI 1.04–1.08), male (aOR 2.59; CI 1.76–3.81), Medicare insurance (aOR 1.93; CI 1.24–3.01), lower income (aORs 0.44 to 0.55 for 2nd to 4th income quartile vs. 1st quartile), > 3 Elixhauser Comorbidity Index (aOR 5.30; CI 3.45–8.15), undergoing Roux-en-Y gastric bypass as opposed to VSG (aOR 3.90; CI 1.79–8.48), and centers performing < 50 BS per year (aOR 5.25; CI 3.38–8.15). Length of stay and hospital cost were also significantly higher in patients with cirrhosis as compared with those with NC. Patients with compensated cirrhosis can be considered for bariatric surgery. However, careful selection of patients, procedure type, and volume of surgical center is integral in improving outcomes and healthcare utilization in patients with cirrhosis undergoing BS.
Coping with being cooped up: Social distancing during COVID-19 among 60+ in the United States.

ABSTRACT Objectives. This study examined the impact of sheltering in place and social distancing among adults aged 60 and older during the 2020 outbreak of COVID-19 in the United States. Methods. Using convenience sampling respondents were asked to complete a web-administered survey to explore impact of social distancing on loneliness, stress, and behavioral changes. The analytic sample consisted of 833 responses of persons aged 60 and older. Results. A large portion reported being stressed (36%), and/or being lonely (42.5%). Nearly 1/3 stated that their sense of loneliness increased during the time of social distancing. Respondents reported engaging in more solitary activity (and fewer in-person activities), using email and text messages more than usual, and spending more time on computers/tablet than usual. Approximately 2/3 reported using more social media than usual. These differed significantly by younger (age 60-70) and older (71+) respondents. Additionally, changes in physical activity, drinking, recreational drug use and sleeping pattern changes differed by age. Conclusions. Social distancing has significant consequences on loneliness and health behaviors among adults in the United States, many of which differ by age group. Results have implications for continued shelter in place practices, but also for any older adult that may be homebound for other reasons.
A systematic review of equine personality

Abstract Examining the literature suggests equine personality is of interest to behavior and welfare scientists and those involved in the equine industry. Study and assessment of personality is critical because of the profound implications certain traits have with respect to injury risk, the horse-human relationship, training processes, learning in horses, and management or breeding practices. The review summarizes the evidence for a genetic basis of personality, the evidence for modification of personality by environment and experience, the measures and tools used in assessing personality, and the traits comprising personality. The review also highlights key considerations for the researcher and areas warranting further study. A literature search was conducted using Google Scholar and Web of Science with the search terms equine and horse in combination with personality and temperament. One hundred thirteen articles were included in the review after exclusion of non-peer-reviewed articles, abstracts, theses, and dissertations. Differences in personality between breeds, estimates of heritability, and identification of specific genes and genetic markers relating to personality illustrate the genetic basis of personality. Further work in identifying specific genes and genetic markers of other personality traits would enable more targeted breeding programs. Experience with their dam, environmental factors such as housing conditions, and training or handling modify a horse’s expression of personality. These factors also present potential confounding variables for the researcher. The effects of the in vivo environment on personality in horses remains unexplored as does the importance of timing over the lifespan for modification and the duration of these effects. Personality is assessed via direct observation and measurement of behavioral, endocrine, cardiac response, or temperature correlates during structured tests or routine management procedures, questionnaires, or a combination thereof. Careful consideration should be given to selection of the most appropriate assessment method given the aims of the study, resources available, and previous validation of the method or methods. Reactivity, gregariousness, reactivity to humans, sensory sensitivity, and locomotor activity are some of the most assessed traits, but no unifying structure of personality is consistently identified across studies. Researchers should give attention to addressing and acknowledging potential confounding variables and selecting an appropriate trait to assess with validated measures.
A Prospect Theoretic Extension of a Non-Zero-Sum Stochastic Eavesdropping and Jamming Game

Wireless networks are susceptible to malicious attacks, especially those involving jamming and eavesdropping. In this paper, we consider a sophisticated adversary with the dual capability of either eavesdropping passively or jamming any ongoing transmission. We investigate a new aspect to consider when designing an anti-adversary strategy to maintain secure and reliable communication: how subjective behavior can impact multi-time slotted communication in the presence of such a sophisticated adversary. To model this scenario we develop a Prospect Theory (PT) extension of a non-zero-sum stochastic game, and derive its PT-equilibrium in closed form for any probability weighting functions. Uniqueness of the PT-equilibrium is proven. Our theoretical results, also supported by simulations, suggest that the anti-adversary strategy is more sensitive to varying network parameters and subjective factors when compared to the adversary’s strategy.
AMERICA'S LARGEST BLACK-OWNED COMPANIES: A 30-YEAR LONGITUDINAL ANALYSIS

This article investigates the largest American black-owned companies over a 30-year period, from 1974 to 2004. Trends with regard to the growth and decline of industry categories and of individual companies, and with regard to these companies' survival rates, are analyzed. Comparable survival rates of small businesses in general, of minority businesses, and of large corporations are investigated. The important factors of corporate minority procurement programs and government minority set-aside programs are evaluated. The phenomenon of large American corporations acquiring some of the most successful black-owned businesses is also studied. These various factors relating to black business success and failure lead to a range of implications and recommendations for current and aspiring minority business owners, as well as to consultants to and researchers of minority business.
An Evaluation of Immersive and Handling Methods for Collecting Salamander Skin Peptides

Amphibian skin secretions are a rich source of antimicrobial peptides that have long interested both the biomedical and herpetological research communities. While anuran skin peptides are well studied, little is known about skin peptides in salamanders, in part because methods for collecting them are poorly developed. In anurans, pharmacological agents are commonly used to stimulate skin peptide responses, thus increasing the amount of peptide collected. It was unclear whether similar methods would work for salamanders. We conducted a series of experiments to test the effects of immersion in pharmaceutical agents (norepinephrine hydrochloride [NE]; acetylcholine chloride [Ach]), handling, and the interaction of both on peptide collection from the skin of Red-Spotted Newts (Notophthalmus viridescens) and Allegheny Mountain Dusky Salamanders (Desmognathus ochrophaeus). Our results suggest that vigorous handling, but not immersion in NE or Ach, is a better method for collecting salamander skin peptides. Despite the widespread use of pharmaceuticals to collect anuran skin peptides, we found little evidence that NE or Ach induces peptide release in salamanders. In fact, we show that inclusion of NE in collection solutions interferes with peptide quantification in protein assays.
An Ever-Underinstitutionalized Party System? A Critical Case Test of Ideological Partisanship

There has been a broad consensus among scholars of party politics that party systems in new democracies differ in some essential way from those of advanced democracies, especially in the level of party system institutionalization. One of the key dimensions of party system institutionalization is some social root of political parties, or ideological linkages to the electorate; party systems in new democracies are known to lack it. However, partisanship in these countries has not been empirically explored to the same extent as it has in old democracies, and ideological linkage to partisanship in East Asian countries has not been directly tested. This paper tests for the impact of ideology on partisanship, using South Korea as a critical case. South Korea has long been notorious for its under-institutionalized party system, despite its OECD member status and high level of industrialization; it is especially critiqued for lack of social roots of its political parties (other than regional ties). By incorporating two different indicators of ideology at the same time – self-placed ideology as a subjective indicator and issue ideology as a more objective indicator – I present strong evidence that the partisanship of this country does have an ideological basis. The issue ideology is aggregated from a series of issue attitudes by item response theory (IRT). Furthermore, by developing this measure, an index of attitudes on key ideological issues, I suggest a new measure of internal coherence of political parties at the public level, which can be widely used in comparison of parties not only within a single country but also across countries. Different levels of party coherence may help explain distinct patterns of party system polarization across countries, as well as the organizational changes and campaigning strategies of individual parties. This measure can provide a new basis for comparing organizational aspects of political parties in new democracies to their Western counterparts.
An improved Particle filter tracking algorithm

In target tracking, if the dynamic model satisfies the Kalman filter assumptions, Kalman filter is optimal, Particle filter is a second-best. Usually, systems are often unable to meet the best, at this time particle filter is usually better than any other filtering method. In order to solve the degradation and deprivation of particle filter in Iteration. This article introduces crossover and mutation operations in the process of sampling and resampling. As the Gabor wavelet is not sensitive to the geometric distortion, brightness change, and noise in the process of describing the objectives, and it is able to achieve a stable tracking for the target with Partial occlusion. So this article construct Gabor wavelet feature template, proposed an improved Particle Filter Algorithm, and implement stable tracking to the target in different contexts.
On Voiculescu’s double commutant theorem

For a separable infinite-dimensional Hilbert space H, we consider the full algebra of bounded linear transformations B(H) and the unique nontrivial norm-closed two-sided ideal of compact operators AC. We also consider the quotient C*-algebra C = B(H)/k with quotient map i7r: B(H) -C. For A any C*-subalgebra of C, the relative commutant is given by A' = {C E C: CA = AC for all A in A}. It was shown by D. Voiculescu that, for A any separable unital C*-subalgebra of C, (VDCT) Al = A. In this note, we exhibit a non-separable unital C*-subalgebra AO of C for which (VDCT) fails.
Initiation of DNA replication in Bacillus subtilis: II. Linkage between termini of parental strands and origins of daughter strands☆☆☆

Abstract Semi-conservative replication, without premature re-initiation, occurred when 5-bromodeoxyuridine was added to thymine-requiring Bacillus subtilis spores which had germinated for three hours in a thymineless medium. When 5-bromodeoxyuridine was added after four hours of thymineless germination, premature re-initiation took place shortly after the first round of replication had begun. Spores were labeled for 30 seconds with 5-[3H]bromodeoxyuridine after thymineless germination. The labeled single-stranded DNA was heterogeneous, with molecular weight averaging 3 × 106 daltons. The buoyant density of this DNA in alkaline cesium chloride was slightly higher than that of normal thymidine strands. Labeled DNA, chased with non-labeled 5-bromodeoxyuridine, showed different density distribution from that of pulse-labeled strands. Density distributions in alkaline CsCl ranged from the density of a heavy, 5-bromodeoxyuridine-substituted, strand to that of a light normal thymidine strand. The frequencies of various densities were nearly equal. No change in this distribution was observed during prolonged chases if spores germinated for three hours in a thymineless medium were used. However, when spores germinated for four hours without thymine were pulse-labeled and chased until re-initiation began, the density of labeled strands shifted to that of the heavy, fully 5-bromodeoxyuridine-substituted strand. The molecular weights of the chased strands were considerably higher than those of pulse-labeled strands, and were similar to the molecular weight of parental strands. These results indicate that pulse-labeled strands are end-to-end hybrids of heavy 5-bromodeoxyuridine-labeled strands linked to termini of light parental strands. These linkages are stable during the first round of replication but are broken upon initiation of the second round of replication. In consequence we propose that replicating B. subtilis chromosomes are circular, covalently joined between parental strands and newly synthesized strands at the origin of replication. The mechanism of initiation and re-initiation is discussed.
Structure and activity of diphtheria toxin. II. Attack by trypsin at a specific site within the intact toxin molecule.

Most preparations of diphtheria toxin that we have examined consist predominantly of mixtures in various proportions of two proteins, each of molecular weight about 63,000. As judged by their electrophoretic behavior on polyacrylamide gels run in the presence of sodium dodecyl sulfate, one of these consists of intact 63,000-dalton polypeptide chains, while the other is composed of two fragments of molecular weight 24,000 and 39,000 (Fragments A and B, respectively) linked by at least one disulfide bridge. Here we report that when these preparations are treated at 25° with low concentrations of trypsin (0.25 to 1.0 µg per ml), a single scission is introduced at a specific site in the former (intact toxin) converting it into a protein apparently identical with the latter (nicked toxin). Thus nicked toxin in the original preparations must be a derivative of intact toxin which arose by attack of proteases from the bacterial culture in which the toxin was produced. Fragment A contains 1 half-cystine residue, and is therefore linked to Fragment B in nicked toxin by one disulfide bridge. Fragment A is stable to heating at 100°, and exposure to pH values from 2 through 12. Fragment B is relatively unstable, and precipitates even at neutral pH. We have shown previously that toxin is almost devoid of enzymic activity unless treated with thiols. The activity is probably entirely due to Fragment A released upon dissociation of nicked toxin in the presence of thiols. When toxin is treated with trypsin the intact chains are converted into a form which can be dissociated by thiols into fragments apparently identical with A and B. Hence the specific activity of the preparation is enhanced by trypsin treatment because of the greater amount of Fragment A released by thiols. The toxicity of toxin is not significantly changed by treatment with trypsin, which indicates that both intact and nicked toxin are toxic. Fragment A alone is not toxic. Linkage to Fragment B is apparently required for toxicity, perhaps to facilitate entry of Fragment A into cells. Treatment of toxin with thiols decreases the toxicity, presumably as a result of dissociation of the nicked fraction into nontoxic Fragments A and B.
Monckeberg sclerosis revisited: a clarification of the histologic definition of Monckeberg sclerosis.

Abstract Context.—Medial calcification of muscular arteries is known as Monckeberg sclerosis (MS). Although this was first described in 1903, disagreement persists over its precise histologic appearance. Some, including Monckeberg, have written that the media alone are calcified, whereas others maintain that both the media and internal elastic lamina (IEL) are involved. Since vascular calcification is of great interest to investigators and clinicians, defined criteria for classifying calcified arterial lesions are important. Objective.—To clarify the histologic definition of MS with regard to calcification of the IEL. Design.—We reviewed slides from 14 incisional and excisional surgical biopsies and autopsy specimens containing arteries with previously diagnosed MS. We looked specifically for medial and IEL calcification and used von Kossa, alizarin red, and trichrome/elastic stains to confirm our findings. We also performed a literature search on the histologic appearance of MS. Results.—Both medial and ...
Amino Acids, Glutamate

Introduction Metabolism Microbial Production Fermentation Method Chemical Properties Dissociation Constant Racemization Properties of l-Glutamic Acid Salt Formation Infrared Spectra Ionic Forms Solubility l-Glutamic Acid Crystal Structure Stability l-Glutamic Acid Hydrochloride Sodium Salt of l-Glutamic Acid Crystal Structure l-Glutamic Acid Monosodium Salt Pentahydrate Calcium Salt of l-Glutamic Acid Industrial Production Extraction Method Industrial Fermentation Method Separation Process Crystallization of l-Glutamic Acid Pyramid Type Centrifugation Transformation of α-Crystals to β-Crystals Crystallization of l-MSG Crystal Shape (Aspect Ratio) Recovery of l-Glutamic Acid from Mother Liquor Uses Seasoning Industrial Use Safety Bibliography Additional Reading Keywords: acceptable daily intake (ADI); brevibacterium; corynebacterium; fermentation process; glutamic acid; polymorph of crystals of glutamic acid α; pyrroridon carboxylic acid (PCA); synergy effect; umami seasoning
Handling The Emotional Response To Disaster: The Case For American Red Cross/ Community Mental Health Collaboration

This paper presents the theory, rationale, and a working model for integrating professional resources at the time of a disaster. Red Cross and community mental health agencies have worked for too long in parallel. A collaborative approach to meeting the emotional needs of disaster victims makes optimal use of indigenous resources; provides skill and knowledge normally lacking in each agency alone; and helps provide, through early intervention, a preventive factor to thwart long term community distress. Options for maintenance of readiness, local or regional adaptation and piloting are also discussed.
Preparation and characterization of single crystal samples for high-pressure experiments

To date, most research utilizing the diamond anvil cell (DAC) at very high pressure has been conducted with polycrystalline samples, thus the results are limited to addressing average bulk properties. However, experiments on single crystals can yield data on a range of orientation-dependent properties such as thermal and electrical conductivity, magnetic susceptibility, elasticity and plasticity. Here, we report new procedures to produce extremely high-quality metallic single crystal samples of size compatible with DAC experiments in the Mbar range. So far, we have produced samples of zinc, Al2O3, cobalt, molybdenum and cerium, and have evaluated the quality of the finished samples with white-light interferometry, synchrotron X-ray diffraction and inelastic X-ray scattering.
Mixing the media for continuing education

The Dental Training Center at the Veterans Administration Hospital in Washington, DC, mixes the media in its continuing education courses to provide personalized and progressive learning experiences. The Dental Training Center at the Veterans Administration Hospital in Washington produces more than 30 educational films annually and provides postgraduate courses for the dental staffs of the Veterans Administration hospitals throughout the country. Various forms of instruction are used in the continuing education courses, including films and slides, closed-circuit television, lectures, demonstrations, and workshops among others.
The brain, biology and evolution in art and its communication

Both art and language are referential and symbolic, but while quite a bit is known about language localisation in the brain, scant little is known about art in that regard. In neurology and neuropsychology, studies of patients with localised brain damage for over 100 years has helped chart the neuroanatomical underpinning of numerous types of cognition. Insight into the neuroanatomical underpinning of aspects of art can be obtained from professional artists who have suffered localised or diffuse brain damage. Similarly, artists with brain damage from birth, known as autistic savants, can provide further help in shedding light into brain and art. The origin of art practice in Homo sapiens existence is important in any discussion of brain and art, as is the relevance of biological motivation shared by animals and humans. These issues are discussed in this article.
The negative reinforcing functions of nonconformity

Employing the general approach which Neal Miller called "extension of liberalized S-R theory," two experiments (N = 108) found that Ss would learn an instrumental response, the reinforcement for which was the opportunity to escape from a situation in which they were a nonconformist. When the nonconformity situations were presented on an intermittent basis, speed of the response was found to be a function of the percentage of nonconformity trials (p <.001). When the opportunity to escape was delayed (0, 1.5, or 3 sec), response acquisition was found to be an inverse function of the length of the delay (p <.001). The results of both experiments correspond to data collected in instrumental escape conditioning experiments on delay of reinforcement and intermittent shock using similar procedures.
Embracing Make Believe Play and Theories of Early Childhood: Understanding Children's Spirituality and the Spiritual Essence of a Young Child

Young children are born with a unique development that captures the spiritual essence of wonder and signature style of their own capabilities, strengths, interests, personality, temperament, and learning styles. Spiritual moments experienced by young children are often direct, personal, and have the effect, if only for a moment, of uplifting us by capturing the essence of spirituality through playful moments. Children’s spirituality involves questioning, exploring, and belonging by building close relationships in comfortable environments and from caring caregivers who provide a secure environment and routine in which to grow and nurture in. Spirituality, together with the efficacy of make-believe play invites young children to be awakened with an awareness of community and purpose with the world around them. Each new discovery made by a young child is a potential source of wonder and delight. Through a child’s imagination and make believe play, teachers and parents may be given opportunities to be aware of this aspect and witness their spirituality. In this paper, children’s spirituality is defined and the characteristics of spirituality are discussed connecting to the dynamics of play for young children and the contributions of major early childhood theorists to the growth and understanding of children’s spirituality are featured.
Polymorphisms of the Beta Adrenergic Receptor Predict Left Ventricular Remodeling Following Acute Myocardial Infarction

Purpose Prior studies demonstrate an association between specific beta-adrenergic receptor (β-AR) polymorphisms and clinical outcomes in patients with chronic heart failure and following acute coronary syndromes. The underlying mechanism may be due to differences in left ventricular remodeling. This study was undertaken to explore the relationship between LV remodeling after myocardial infarction and polymorphisms in the cardiac β1-AR and β2-AR genes.
Glutathione peroxidase: inhibition by cyanide and release of selenium

Abstract Treatment of highly purified ovine erythrocyte glutathione peroxidase with KCN resulted in loss of enzyme activity and release of selenium from the enzyme. The inactivation by cyanide was time-dependent and the rate was strongly influenced by temperature, concentration of cyanide, oxidation state of the enzyme, and pH. The pH effect could be explained on the basis of the increasing proportion of cyanide ion with increasing pH. Inhibition could be prevented by prior reduction of the purified enzyme with glutathione, dithiothreitol, or dithionite. Oxidation with cumene hydroperoxide was necessary to demonstrate cyanide inhibition of glutathione peroxidase activity in rat liver cytosol. These observations explain why cyanide inhibition of glutathione peroxidase has not been noted previously and provide new approaches for studying the chemical nature of the enzyme-selenium.
Ontogenetic growth (Communication arising): Modelling universality and scaling

Of the equations that have been used to describe ontogenetic growth in terms of the rate of increase in mass, m, as a function of time, t, most are merely statistical descriptions with no mechanistic basis. Our model1 is derived from fundamental biological and physical principles and relates growth to metabolic power at the cellular level. It is based on the allocation of resources to the maintenance and replacement of existing tissue and the production of new tissue, with the whole-body metabolic rate B = NcBc + Ec(dNc/dt), where Bc is the cellular metabolic rate, Ec is the energy needed to create a cell, and Nc is the total number of cells. As m = Ncmc, where mc is the average cell mass, this gives where a = B0mc/Ec, b = Bc/Ec, β = 1 and α is the allometric exponent for B (≡B0mα), taken to be 3/4 in accordance with a large body of data and with theoretical arguments2,3. The asymptotic mass, for which dm/dt = 0, is predicted to be M = (B0mc/Bc)4.
The Effective Use of Color for Text on the IBM 5153 Color Display

The goal of this research was to provide a set of criteria for the effective use of color on the IBM 5153 Color Display. Available guidelines provide direction but not the detail required for application programmers. This study examined character legibility and subjective preference for color combinations in text in an application program. The effectiveness of color combinations was defined as a joint function of response time and subjective rating. The graphs of foreground/background color relationships show the observers' performance as a function of their preference. The results indicated the flexibility of black or blue backgrounds. The findings are discussed with respect to principles of human perception.
Iterative weighted risk estimation for nonlinear image restoration with analysis priors

Image acquisition systems invariably introduce blur, which necessitates the use of deblurring algorithms for image restoration. Restoration techniques involving regularization require appropriate selection of the regularization parameter that controls the quality of the restored result. We focus on the problem of automatic adjustment of this parameter for nonlinear image restoration using analysis-type regularizers such as total variation (TV). For this purpose, we use two variants of Stein's unbiased risk estimate (SURE), Predicted-SURE and Projected-SURE, that are applicable for parameter selection in inverse problems involving Gaussian noise. These estimates require the Jacobian matrix of the restoration algorithm evaluated with respect to the data. We derive analytical expressions to recursively update the desired Jacobian matrix for a fast variant of the iterative reweighted least-squares restoration algorithm that can accommodate a variety of regularization criteria. Our method can also be used to compute a nonlinear version of the generalized cross-validation (NGCV) measure for parameter tuning. We demonstrate using simulations that Predicted-SURE, Projected-SURE, and NGCV-based adjustment of the regularization parameter yields near-MSE-optimal results for image restoration using TV, an analysis-type 1-regularization, and a smooth convex edge-preserving regularizer.