cssi/SciSciGPT-SciSciNet huggingface dataset:
Increased mechanosensitivity and nuclear stiffness in Hutchinson–Gilford progeria cells: effects of farnesyltransferase inhibitors

Hutchinson-Gilford progeria syndrome (HGPS), reportedly a model for normal aging, is a genetic disorder in children marked by dramatic signs suggestive for premature aging. It is usually caused by de novo mutations in the nuclear envelope protein lamin A. Lamins are essential to maintaining nuclear integrity, and loss of lamin A/C results in increased cellular sensitivity to mechanical strain and defective mechanotransduction signaling. Since increased mechanical sensitivity in vascular cells could contribute to loss of smooth muscle cells and the development of arteriosclerosis--the leading cause of death in HGPS patients--we investigated the effect of mechanical stress on cells from HGPS patients. We found that skin fibroblasts from HGPS patients developed progressively stiffer nuclei with increasing passage number. Importantly, fibroblasts from HGPS patients had decreased viability and increased apoptosis under repetitive mechanical strain, as well as attenuated wound healing, and these defects preceded changes in nuclear stiffness. Treating fibroblasts with farnesyltransferase inhibitors restored nuclear stiffness in HGPS cells and accelerated the wound healing response in HGPS and healthy control cells by increasing the directional persistence of migrating cells. However, farnesyltransferase inhibitors did not improve cellular sensitivity to mechanical strain. These data suggest that increased mechanical sensitivity in HGPS cells is unrelated to changes in nuclear stiffness and that increased biomechanical sensitivity could provide a potential mechanism for the progressive loss of vascular smooth muscle cells under physiological strain in HGPS patients.
Computer-aided extraction of the features of the EMG of single motor units.

A software-based system is presented for feature extraction of compound, action-potential (EMG) recordings from single motor units. It simplifies and automates the measurement and analysis of several parameters of the action potential: peak-to-peak amplitude, total duration, peak-to-peak duration, and total area. The software is based on a simple algorithm that first finds the baseline (isoelectric line; including a noise level) of each single EMG potential (waveform) and then searches for the minimum and maximum values in the array of data points representing it. The algorithm searches in both directions starting from the minimum and maximum data points (the waveform peaks) to find the beginning and ending points of the waveform. Using the indices (i.e., array-point numbers) of the four data points provided by the algorithm, the desired features are extracted and/or calculated and saved in a standard-format spreadsheet. The algorithm has a potentially widespread usefulness in a broad array of electrophysiological studies.
Hierarchy for Imbedding-Distribution Invariants of a Graph

Most existing papers about graph imbeddings are concerned with the determination of minimum genus, and various others have been devoted to maximum genus or to highly symmetric imbeddings of special graphs. An entirely different viewpoint is now presented in which one seeks distributional information about the huge family of all cellular imbeddings of a graph into all closed surfaces, instead of focusing on just one imbedding or on the existence of imbeddings into just one surface. The distribution of imbeddings admits a hierarchically ordered class of computable invariants, each of which partitions the set of all graphs into much finer subcategories than the subcategories corresponding to minimum genus or to any other single imbedding surface. Quite low in this hierarchy are invariants such as the average genus, taken over all cellular imbeddings, and the average region size, where “region size” means the number of edge traversals required to complete a tour of a region boundary. Further up in the hierarchy is the multiset of duals of a graph. At an intermediate level are the “imbedding polynomials.” The hierarchy is explored, and several specific calculations of the values of some of the invariants are provided. The main results are concerned with the amount of work needed to derive one invariant from another, when possible, and with principles for computing the algebraic effect of adding an edge or of otherwise combining two graphs.
Pathology Quiz Case

A 71-YEAR-OLD MALE INMATE presented to the otolaryngology service with a 9-month history of an enlarging, painful lesion involving the right side of the upper lip and nose. Initially, the patient noted a “pimple” that did not respond to topical and oral antibacterial therapy. His medical history was remarkable for the removal of a skin cancer on his lower lip 14 years ago at an outside facility. He denied systemic complaints, except for an episode of mild pneumonia 1 year before presentation that had resolved with oral antibiotic therapy. He denied sick contacts, travel, or occupational exposures. He had a 15 pack-year smoking history. Physical examination revealed a 3 3-cm raised, crusted lesion distorting the right side of the upper lip and the right nasal vestibule. The lesion extended superiorly to the columella and inferiorly to the vermilion border (Figure 1). The results of the rest of the head and neck evaluation, including fiberoptic nasopharyngolaryngoscopy, and general physical examination were unremarkable. The findings of a biopsy were consistent with actinic keratosis. Progression of the lesion was noted at followup; however, the findings of a second biopsy were nondiagnostic. A third biopsy was performed. The histopathologic features seen on hematoxylin-eosin (Figure 2) and methenamine silver (Figure 3) staining were diagnostic. Computed tomographic scans of the chest and abdomen revealed bilateral pulmonary nodules and linear interstitial opacities (Figure 4), left hilar adenopathy, and bilateral adrenal gland enlargement. What is your diagnosis?
Role of cytokines in bone resorption

Osteoclastic bone resorption is modulated in humans by powerful osteotropic factors which are generated in the immediate vicinity of bone resorbing surfaces. These factors are released from marrow mononuclear cells and from some bone cells, and some are actually incorporated into the noncollagenous bone matrix from where they are released when bone is resorbed. They are likely important not only in the control of normal bone remodeling, but also in a number of disease states associated with disordered remodeling. In this review, current concepts of the effects of these factors on cells in the osteoclast lineage will be discussed.
Application of electron beam to inactivate Salmonella in food: Recent developments

Abstract Food is a transmission vehicle for Salmonella that causes about 96% of all salmonellosis cases. The high frequency and incidence of foodborne outbreaks makes Salmonella a significant public health concern and economic burden worldwide. Although thermal pasteurization is commonly applied to food products to inactivate Salmonella , heat simply cannot be used for fresh food products such as produce, eggs, and many ready-to-eat (RTE) foods. It has also been demonstrated that Salmonella can survive thermal pasteurization in peanut butter. Besides an on-going concern with Salmonella in eggs, the recent outbreaks in fresh produce and peanut butter clearly indicate a need for non-thermal technologies to adequately inactivate this pathogen. Electron beam (e-beam) uses linear accelerator to accelerate electrons from electricity to near-speed-of-light. As with other types of ionizing radiation, e-beam inactivates microorganisms directly by DNA damage resulting in reproductive death and indirectly by free radicals generated during water radiolysis that disintegrate cell membrane. Since e-beam inactivates microorganisms non-thermally, it may be used to inactivate Salmonella in fresh food products such as produce, eggs, RTEs, and peanut butter. A new development is secondary emission electron gun (SEEG) e-beam. This compact SEEG e-beam has a potential to be incorporated into a microwave oven. This incorporation would allow non-thermal inactivation of foodborne pathogens including Salmonella at the point-of-consumption (i.e., household level and food service). This article reviews the application of e-beam to inactivate Salmonella in various food matrices with an emphasis on most recent Salmonella outbreaks. The article also succinctly reviews the latest understanding of the mechanism of microbial inactivation by e-beam and radio-resistance as well as microbial inactivation kinetics.
Personal Credentialing and the Professionalization of Health Education

(1998). Personal Credentialing and the Professionalization of Health Education. Journal of Health Education: Vol. 29, No. 2, pp. 121-125.
CALL in the K-12 Context: Language Learning Outcomes and Opportunities

This review of CALL research in K-12 contexts is structured around two distinct bodies of research, each of which generates different types of questions emerging from the diverse demands of elementary and secondary education. The first area focuses on learning outcomes and builds on the use of conventional measures of learner achievement and instructional efficacy to help guide systematic decisions about innovations in curriculum and assessment. At stake from an outcome orientation is how technology might amplify the pace, reach, and efficacy of using technology to move students toward established curricular goals. The second area views new technologies as the site of learning opportunities , and researchers in this vein ask how to rethink which goals are targeted, which assessments are retooled, and which new areas of learning are forged with digital tools. The affordances of new technologies are viewed as products of a steady stream of innovation that offers novel learning environments, expanded semiotic resources, and new modes of communication. We begin with an orientation to K-12 language education contexts as a backdrop to our central focus on synthesizing current CALL research, and we conclude by discussing the challenges and possibilities of integrating technology into K-12 language education.
Biomechanical destruction of cancer cells in skeletal muscle: a rate-regulator for hematogenous metastasis

Following left ventricular injection into mice, B16 melanoma and Ehrlich ascites tumor cells are arrested in the microvasculature of the quadriceps femoris muscles. Within 5 min of delivery the effects of variation in surrounding tissue pressure on the survival of the arrested cells have been determined by bioassays of denervated (relaxed), non-contracting or contracting muscle.
Using Technology to Connect Students with Emotional Disabilities to General Education

This case follows a high-school special-education teacher who teaches in a program for students with emotional disturbance ED in a large, comprehensive high school. Many of her students cannot attend general-education classes because of anxiety or behavioral issues, but as a special educator, she does not have the subject-area expertise to provide them with the academic education they need to be prepared for life after high school. She hopes that through the use of a video connection to general-education classes her students can be exposed to the highly qualified content-area teachers while remaining in the safe environment of the ED classroom. She believes that virtual attendance in a class could help her students feel comfortable enough to make the move to the actual classroom and be included with their peers to gain academic knowledge and social skills.
Iron binding by phosvitins: variable mechanism of iron release by phosvitins of diverse species characterized by different degrees of phosphorylation.

Abstract The rate of reductive iron release from Fe(III) complexes of phosvitins of diverse fish species, at varied initial degrees of saturation with iron, was studied with particular attention to the effect of the degree of phosvitin phosphorylation on the kinetics of iron release. The reaction was followed colorimetrically as phosphorprotein-bound iron was transferred to an excess of o -phenanthroline, in the presence of hydroquinone as a reducing agent. The principal finding was the variability of the kinetic order or iron release by phosvitins, depending on their degree of saturation with iron and the extent to which their serine residues were phosphorylated. Highly phosphorylated proteins, especially at high initial degrees of iron saturation, obey first-order kinetics. Partially phosphorylated proteins, especially at low initial degrees of iron saturation, release their iron in a zero-order fashion. First-order rates imply that the iron binding sites are kinetically independent of each other. Zero-order behavior appears to reflect iron release from hypothetical iron-binding clusters serving as kinetically effective reactive centers of unchanging concentration for most of the time course of the reaction. Variations of the initial degree of iron saturation of given phosvitins produce variations in their kinetic behavior. The results are considered in terms of a dynamic model of phosvitin iron binding sites which may constitute themselves diversely, in response to the amount of iron that is to be accommodated, or may reconstitute themselves as their molecular environment becomes altered.
Enhancing hepatocyte adhesion by pulsed plasma deposition and polyethylene glycol coupling.

Decreased hepatocyte adhesion to polymeric constructs limits the function of tissue engineered hepatic assist devices. We grafted adhesion peptides (RGD and YIGSR) to polycaprolactone (PCL) and poly-L-lactic acid (PLLA) in order to mimic the in vivo extracellular matrix and thus enhance hepatocyte adhesion. Peptide grafting was done by a novel technique in which polyethylene glycol (PEG)-adhesion peptide was linked to allyl-amine coated on the surface of PCL and PLLA by pulsed plasma deposition (PPD). Peptide grafting density, quantified by radio-iodinated tyrosine in YIGSR, was 158 fmol/cm2 on PLLA and 425 fmol/cm2 on PCL surfaces. The adhesion of hepatocytes was determined by plating 250,000 hepatocytes/well (test substrates were coated on 12 well plates) and quantifying the percentage of adhered cells after 6 h by MTT assay. Adhesion on PCL surfaces was significantly enhanced (p < 0.05) by both YIGSR (percentage of adhered cells = 53 ± 7%) and RGD (53 ± 12%) when compared to control surfaces (31 ± 8%)....
Behavioural Differences between Chinese–American and European–American Newborns

IN the course of an investigation of newborn behaviour among widely distributed ethnic groups, some interesting preliminary results have appeared.
Lifetimes and transition probabilities in CO

Abstract The mean lifetime of theB2Σ state of CO+ in the levels υ′ = 0, 1, 2 was determined to be 39·5±4 nsec by means of the phase shift method. A modulated electron beam was used for excitation. Modulation frequencies from 0·54 Mc to 54 Mc were used to facilitate the study of cascading. A zero phase reference was obtained from the atomic lines H I, 1216Aand N II, 1086A, and the effect of cascading on the phase shifts of these transitions was investigated. Values ofAυ′υ are given for some of the stronger bands of theB2Σ -X2Σ system.
Vertical profiles of boundary layer conductance and wind speed in a cotton canopy measured with heated brass surrogate leaves

Abstract Knowledge of single leaf boundary layer conductance ( g b ) within extensive canopies is required to scale stomatally regulated gas exchange from leaf to canopy. Fluxes of terpenes and heat, formation of dew, and other processes occurring at the leaf surface may be controlled by g b . We develop, test, and deploy at five canopy heights, a set of paired, heated and unheated brass surrogate leaves, with realistic 3-dimensional shape and characteristic dimension ( d ) for cotton ( Gossypium hirsutum L.) in California. An equation describing heat transfer from a flat plate, enhanced by a factor of 1.15 for complex leaf shape, adequately described g b of the surrogate leaves. In the field, values of g b measured with the surrogate leaves near the top of the canopy were closely related to wind speed, as expected from theory. The dependence of g b on leaf size was apparent at all heights in the canopy using surrogate leaves differing in d . The profile of within-canopy wind speed ( u ) was determined using the profile of g b and d of the surrogate leaves. This profile of effective u in the leaf environment was well described by a conventional exponential decay model with an empirically derived wind extinction coefficient ( K = 1.5). This profile of u was combined with the directly measured profile of d of biological leaves to determine the actual profile of g b in this canopy. The increasing leaf size toward the middle of the canopy caused actual g b to decline more steeply than predicted from constant d . With depth in the canopy sunflecks increasingly contributed to unequal radiation interception between paired surrogate leaves and therefore to anomalies in calculated g b . A simple data filtering protocol, rejecting data outside the range observed at the top of the canopy, is introduced. Data rejection increased appropriately with increasing sunfleck frequency and depth in the canopy. These results extend the applicability of the heated, paired surrogate leaf technique to sheltered positions in dense canopies, and to large-leafed species, allowing direct measurement of an important canopy parameter ( g b ) that has typically been estimated or calculated as a residual.
Childhood trauma and personality disorder: toward a biological model

Cross-sectional and prospective associations of personality disorder with childhood trauma provide an important clue regarding the biological mechanism of personality disorder. In this review, empirical literature from several domains is summarized. These include relevant findings from behavioral genetics, preclinical models of early life parental care, and clinical translational studies of personality disorder. Identification of the biological mechanism by which childhood trauma exerts an effect on personality disorder may require modification of the conceptualization of personality disorder, either as a set of categories or dimensions.
Molecular cloning and chromosomal mapping of a candidate cytokine gene selectively expressed in human CD34+ cells.

Abstract A rare population of human bone marrow (BM) and cord blood (CB) mononuclear cells bearing the CD34 surface marker (CD34 + ) function as hematopoietic stem/progenitor cells. Cells lacking CD34 expression (CD34 − ) in BM and CB are largely mature hematopoietic cells of various lineages that are derived from the CD34 + cells. To elucidate molecular mechanisms governing functional differences between CD34 + and CD34 − hematopoietic cells, we used representational difference analysis (RDA)-based subtraction to identify genes that are specifically or preferentially expressed in CD34 + cells. Among the 73 RDA fragments initially sequenced, 30% are derived from the CD34 and c- kit genes that are preferentially expressed in CD34 + cells. An additional 27 (37%) are novel or homologous only to entries in expressed sequence tag databases. One (C17) was found four times and is expressed in CD34 + but not in CD34 − cell populations from CB or BM. The cloned C17 cDNA encodes a novel polypeptide of 136 amino acids with a signal sequence. No homology to this peptide was found in the public databases. A secondary-structure analysis predicts that the C17 peptide contains four α-helices, a characteristic of hematopoietic cytokines and interleukins. This novel gene is mapped to human chromosome 4p15–p16.
The Children's Bureau and Passage of the Sheppard-Towner Act of 1921: Early Social Work Macro Practice in Action

The Sheppard-Towner Act of 1921 was the first major piece of federal legislation passed in the United States to focus on infant and maternal health. Following its implementation, the U.S. infant mo...
Economics of Soil Conservation from the Farmer's Perspective: Discussion

capital theory problems but in the case of soil conservation are compounded by the lack of knowledge, measurement problems, and important distinctions between quantity and quality dimensions. In the above setting, a number of perspectives are possible. SS provide us with two perspectives. They begin their paper with a public policy perspective arguing that an understanding of farmers' behavior is essential in the development of policy instruments that will achieve social objectives. However, they end their paper with an educational function perspective in which we are charged the responsibility of developing optimal private strategies that might be pursued by farmers who fail to have adequate knowledge or know their own best interest. In this discussion, I will focus on the first perspective since it subsumes the second.
Girdling-induced nutrient accumulation in above ground tissue of peanuts and subsequent feeding by Spissistilus festinus, the three-cornered alfalfa hopper

Changes in nutrient partitioning in stems and leaves of peanut (Arachis hypogaea L.) were examined after girdling of stems by Spissistilus festinus (Say) (Homoptera:Membracidae), the three-cornered alfalfa hopper. Under field conditions amino acids increased more than 12-fold in concentration in the 2 cm stem section above the girdle compared to below the girdle or control stems for newly formed girdles (less than 7–11 days). Asparagine and proline were the predominant amino acids, and increased 40- and 60-fold, respectively, above the girdle compared to below the girdle. There was no buildup of nutrient assimilates for the older girdled stems that had callused (and presumably recovered from feeding injury). A time course from 1–11 days was followed under greenhouse conditions, and girdled regions remained enriched in sugars for one day and amino acids for four days after girdle formation. After girdle formation most S. festinus responded to nutrient sinks by feeding within 5 mm above the girdle. This behavior was most pronounced one day after girdle formation, but persisted for seven days after girdle formation. During this period a new girdle was often formed within 10 mm above the original girdle. Under field conditions, stems and leaves derived from stems that had sustained an early or late season girdle generally had a reduced dry weight, total nitrogen content, and total carbon content; however, significant differences did not always occur. Thus, although temporary changes occurred in nutrient partitioning in girdled stems, there appears to be longer term negative growth effects on leaves and stems.
Synaptic membrane antigens in developing rat brain cerebral cortex and cerebellum.

: The contents of five synaptic membrane antigens (56K, 58K, 62K, 63K, and 64K) were determined in rat cerebral cortex and cerebellum at eight developmental time points: E9, E14, P < 1, P5, P14, P28, P60, and P180 (E, embryonic; P, postnatal). In cerebral cortex, the five antigens showed five different developmental patterns with respect both to specific content (i.e., quantity per unit of membrane) and total content (i.e., quantity per cortex). The 56K, 58K, and 62K polypeptides were first detected at E14, increased slightly to P5, then increased rapidly from P5 to P28 by 14-, 11-, and 18-fold, respectively. From P28 to PI80, the patterns of these antigens showed very large differences. The 63K and 64K antigens were first detected at P14 and P28, respectively. The specific content of 63K antigen continued to increase steadily throughout adult life; in contrast, the specific content of the 64K antigen did not change appreciably. In cerebellum only three antigens (56K, 58K, and 62K) were detected. These three antigens showed different developmental patterns. The 56K polypeptide was first detected at E14; its specific content increased very rapidly to a maximum at P < 1; it then decreased, first slowly, and then more rapidly, disappearing at P60. The 58K polypeptide also was detectable at E14 and increased very rapidly to a maximum at P < 1. It then decreased markedly to P5, followed by an increase, returning almost to its maximum level at P14. It then slowly decreased disappearing at P180. The 62K antigen was first detected at P14 and then it slowly decreased with disappearance at P60. The patterns with respect to total contents per cerebellum were similar for the three antigens, with a maximum at P28. We conclude that the highest increase in the contents of these antigens roughly corresponds to the period of maximal synaptogenesis (P9 to P28) in both regions. Differences among developmental patterns probably reflect changing molecular machinery required for development and functional differentiation of synapses in different brain regions. The fine structure of these patterns suggests that the quantitative measurement of synaptic membrane antigens will be useful for delineating complex processes occurring during synaptogenesis.
Micro Grid Stability Improvements by Employing Storage

Storage devices can be used in a power grid to store the excess energy when the energy production is high and the demand is low and utilize the stored energy when the produced energy cannot meet the high demands of the consumers. This paper represents two different studies of micro grid consisting of a conventional synchronous generator, as well as renewable energy sources, energy storage, and loads in order to investigate the effective energy flow control and transient stability improvement by employing storage. Thermal storage, unlike electrical one (such as battery) is more environmental friendly, has longer life span, and is more effective in power flow control. In this paper, resistive type thermal storages are proposed and its stability effects on micro grids are evaluated. A suitable model is developed for the storage and the grid's stability analysis is adopted by using linearization methods. Consequently, by designing an optimal controller for the storage the stability of the micro grid is improved as verified through the simulations.
Minimizing mean flow time with release time constraint

Abstract We consider the problem of preemptively scheduling a set of n independent tasks with release times on m identical processors with the objective of minimizing the mean flow time. For one processor, Baker gives an O(n log n) time algorithm to find an optimal schedule. Lawler asks the question whether the problem can be shown to be solvable in polynomial time or shown to be NP-hard for m⩾2. In this paper we answer this question by showing that it is NP-hard for each fixed m⩾2.
Dobutamine stress echocardiography for the preoperative evaluation of patients undergoing lung volume reduction surgery.

Abstract Background: Lung volume reduction surgery has been proposed as a bridge to lung transplantation and as definitive therapy for advanced chronic obstructive lung disease. However, patient selection criteria and optimal preoperative assessment have not been clearly defined. Objective: We investigated the feasibility, safety, and value of dobutamine stress echocardiography as a predictor of major early cardiac events in patients who underwent lung volume reduction surgery. Methods: The study population consisted of 46 patients (21 men and 25 women, mean age 59 ± 9 years) who underwent dobutamine stress echocardiography (maximum dose 40 μg · kg –1 · min –1 plus atropine if needed) 180 days or less before lung volume reduction surgery. Adverse cardiac events were prospectively defined and tabulated during hospitalization after the operation and at subsequent outpatient visits. Results: Dobutamine stress echocardiography was interpretable in 45 of 46 (98%) patients. There were no adverse events during testing. The studies revealed normal left ventricular systolic function at rest in all patients and normal right ventricular function in all patients but one. Thirteen patients had right ventricular enlargement. Estimated right ventricular systolic pressure was mildly elevated (>40 mm Hg) in 5 patients. Four patients (9%) had stress tests positive for ischemia. There were no perioperative deaths. Follow-up was available for 44 of 45 patients at a duration of 20.0 ± 7.0 months. Two major adverse cardiac events occurred in the same patient in whom the results of dobutamine stress echocardiography were positive for ischemia (positive predictive value 25%, 95% confidence interval 0% to 83%; negative predictive value 100%, 95% confidence interval 90 to 100%). Conclusion: Despite end-stage chronic obstructive lung disease and poor ultrasound windows, dobutamine stress echocardiography is feasible and safe in patients undergoing evaluation for lung volume reduction surgery. It yields important information on right and left ventricular function and has an excellent negative predictive value for early and late adverse cardiac events. (J Thorac Cardiovasc Surg 1999;118:542-6)
The origin of the emission lines shown by RW Tauri and other binary systems

It is proposed that the observed double-component emission lines originate from the triangular Lagrangian points, L4 and L5, of the restricted three-body problem. The light curves of many close binary systems show absorption dips at ±60° of the primary (and sometimes also the secondary) minimum, indicating appreciable accumulation of matter at these points. The orbital velocity of L4 and L5 is derived as a function of period and the masses of the component stars. This equation is an independent relationship for determining the two stellar masses. It also reproduces Struve's empirical finding ofV3∝P−1. The observed emission line velocity is consistently higher than the calculated orbital velocity of L4 and L5. This is due to the serious erosion of the low velocity sides of the emission components by the stellar and shell absorption lines. There are observational evidences which indicate the intermittent high velocity radial ejection of matter to be a mode of mass loss from the secondary. And the energy of mass motion from this ejection is sufficient, and may be responsible, for heating the gas at L4 and L5. The ionizing radiation emitted by the primary of the Algol systems is many orders of magnitude below that required by the observed strength of the emission lines. Some related discussion is also given to nova and dwarf nova systems.
Dynamical Mass Generation in the Continuum Thirring Model

Abstract We study the renormalization of the Thirring model in the neighbourhood of μ=0, g =- π /2, and find that on the trajectory which tends to this point when the scale goes to infinity the behaviour of the model reproduces what one obtains decomposing the N = 2 Gross-Neveu model. The existence of this trajectory is consistent with the dynamical mass generation found by McCoy and Wu in the discrete version of the massless model.
Response of the annual and zonal mean winds and temperatures to variations in the heat and momentum sources

Comparisons are made among solutions to zonal-mean equations obtained with parameterized friction and radiative cooling and those forced from specified heat and momentum sources. Budget equations are defined for zonally averaged steady state responses in a thin spherically rotating atmosphere. The heat sources and sinks and mean meridional circulation that maintain observed annual and zonal mean temperatures are identified with a diagnostic calculation. Estimates are made of the surface sensible heating, atmospheric latent heating and vertical flux eddy divergences. The heat and moisture sources and sinks are varied to obtain the steady state responses. The Hadley circulation is fairly insensitive to changes in the strength of the eddy momentum flux when sufficient internal friction is present. Varying the width of the total precipitation of the intertropical convergence zone with fixed eddy fluxes and extratropical heat sources yields conditions similar to El Nino. Finally, a minimum speed is found for the jet stream after varying the horizontal eddy momentum fixing latent and eddy heat sources.
Schistosoma mansoni: Mechanisms in regulation of glycolysis

Abstract Adult pairs of Schistosoma mansoni convert glucose to lactate rapidly and almost quantitatively under aerobic and anaerobic conditions E. Bueding, 1950 , Journal of General Physiology33, 475–495). Glycolysis is the principal source of energy of schistosomes and its inhibition by trivalent organic antimonials, at the phosphofructokinase step [EC 2.7.1.11], may be the basis for the chemotherapeutic effects of these agents E. Bueding and J. M. Mansour, 1957 , British Journal of Pharmacology and Chemotherapy12, 159–165). We have developed standardized conditions for the comparison of rates of glucose consumption and lactate production by intact schistosomes in vitro and by centrifuged homogenates of worms. The rates of glycolysis of homogenates prepared from freshly isolated worms, and from worms that have been lyophilized immediately after harvesting and stored for prolonged periods at −80 C were identical, when measured in media containing appropriate concentrations of glucose, NAD, ATP, MgCl2, KCl, and phosphate. The specific activities of the 11 glycolytic enzymes and of 3 related enzymes (fructose-biphosphatase [EC 3.1.3.11], glycerol-3-phosphate dehydrogenase [EC 1.1.1.8], and malate dehydrogenase [EC 1.1.1.37]) were measured in homogenates under optimal conditions. The profile of the relative activities of glycolytic enzymes of S. mansoni resembles closely that of Ehrlich ascites tumor cells, and differs markedly from that observed in erythrocytes or skeletal muscle. As is the case in many animal tissues, hexokinase [EC 2.7.1.1] was the enzyme of lowest specific activity, and the rate of glycolysis of homogenates was almost the same as the hexokinase activity. Several other lines of evidence support the view that the hexokinase reaction is the rate-limiting step in the glycolysis of worm homogenates. Hexokinase activity was not particulate in schistosome homogenates, and there was no detectable high Km glucokinase-like activity. The rate of glycolysis by homogenates exceeded that of intact worms by a factor of nearly 5. The contributions of glucose transport, availability of ADP and inorganic phosphate, regulatory enzymes, and a substrate cycle catalyzed by fructose-bisphosphatase are considered as possible mechanisms for the restraint of glycolysis in intact worms. The mechanisms contributing to the rapid rates of glycolysis of adult S. mansoni have not been identified, although several can be excluded (unusually high capacity of the glycolytic enzymes, the presence of mitochondrial hexokinase, the occurrence of glycosomes, and the operation of defective mitochondrial shuttles). In view of the regulatory role of hexokinase in the glycolysis of S. mansoni, inhibition of this enzyme is a potentially important target for the development of new antischistosomal drugs.
Undergraduate data communications and networking projects using opnet and wireshark software

The national importance of creating "content reflecting cutting edge developments in STEM fields" has been recognized the National Science Foundation. The National Research Council has also noted that creating engaging laboratory and classroom experiences is a challenge to effective undergraduate education in STEM disciplines. In this paper we present our endeavors to address these issues in the field of computer networks. We discuss our experiences with novel laboratory and classroom projects using OPNET and Wireshark software products in undergraduate networking courses. These laboratories help undergraduate students understand fundamental networking concepts through modeling and simulation of computing systems. We have found that their use enhances student learning and interest in the subject of computer networks.
Radio Continuum and Radio Recombination Line Observations of Sagittarius B1 and G0.6-0.0

Continuum emission and H110-alpha recombination line emission from Sgr B1 and G0.6-0.0 have been observed using the VLA. It is shown that Sgr B1 is a region of great complexity, both spatially and kinematically. The continuum observations show that this region is dominated by many extended features rather than compact sources. On the other hand, Sgr B2 is dominated by several ultracompact H II regions. The two regions may be in different stages of evolution, with Sgr B1 being older, perhaps by as much as 0 exp 6 yrs. The recombination line study shows that Sgr B1 is composed of two distinct kinematic regions, a simple western one and a more complex eastern one. G0.6-0.0 is a region composed of at least four ultracompact H II regions that is situated between Sgr B1 and Sgr B2. There is an arc of ionized gas that lies to the east and to the south of these compact regions. The velocity of G0.6-0.0 is intermediate between those of Sgr B1 and Sgr B2. These facts strengthen the argument that these regions are physically associated.
Bantu World and the origins of a captive African commercial press in South Africa

(1988). Bantu World and the origins of a captive African commercial press in South Africa. Journal of Southern African Studies: Vol. 14, No. 3, pp. 351-370.
Erythrocyte membrane abnormalities in human myotonic dystrophy

Abstract Membrane-bound enzyme activities and cardiac glycoside binding were determined in red blood cell membrane preparations from patients with myotonic dystrophy and in age matched controls. Na + -K + -activated ATPase activity was signficantly increased in myotonic patients. [ 3 H]Ouabain binding to erythrocyte membranes was also significantly increased in myotonic dystrophy patients. The Mg 2+ -ATPase (ouabain-insensitive) was, however, unchanged. The K + -stimulated paranitrophenyl phosphatase (KPNPPase) activity was markedly enhanced in myotonic patients as compared to controls. The kinetic analysis showed a marked change in V max of Na + -K + ATPase with respect to the activation by Na + , K + and ATP. However, the K m values were the same in control as well as in myotonic groups. The increased erythrocyte membrane Na + -K + -ATPase activity, KPNPPase and [ 3 H]ouabain binding in myotonic patients supports the hypothesis that generalized membrane abnormality may be involved in pathogenesis of the human myotonic dystrophy.
The science and nonscience of psychologists' responses to The Bell Curve.

To serve racially diverse clients effectively, professional psychologists should understand the range of scientific and social forces shaping their own and their clients' lives. A manifestation of such forces, the 1994 publication of R. J. Herrnstein and C. Murray's The Bell Curve: Intelligence and Class Structure in American Life was an attempt to influence both psychological knowledge and U.S. politics. This article analyzes the book and 5 psychologist authors' responses to it. The responses fell far short of providing a critical analysis of the book's racially biased argument and did little to reduce the misleading picture of race and IQ that the book promulgated. Scrutinizing the whole book-especially connections among scientific knowledge, proposed policy, and professional practice with attention to the "code logic" used-will enable practitioners to recognize and change subtle aspects of racial dynamics that occur in their work.
Impurity scattering in d-wave superconductivity. Unitarity limit versus Born limit

As is well known, Zn-substitution of Cu in the Cu-O2 plane in the hole-doped high Tc cuprates provides a semi-quantitative test of underlying d-wave superconductivity. Here we complement this with a parallel study of Ni-substitution, which gives rise to weak scattering described with the Born approximation.
A counter-example for “a simpler construction for showing the intrinsically exponential complexity of the circularity problem for attribute grammars”

Jazayeri [J. ACM 28, 4 (Oct. 1981), 715-720] proposes a simpler construction for use in the proof by Jazayeri et al. [Commun. ACM 18, 12 (Dec. 1975), 697-706] that the circularity problem for attribute grammars has inherent exponential time complexity. The simplification introduces a flaw that invalidates the proof. The flaw can be corrected, at the cost of eliminating some of the simplification claimed for the new construction.
Brachyolmia, recessive type (Hobaek): a clinical, radiographic, and histochemical study

Brachyolmia recessive type (Hobaek) is a rare bone dysplasia characterized by short trunk dwarfism that becomes evident during childhood. The radiographic manifestations are primarily limited to the spine, and consist of universal platyspondyly with lateral extension of the vertebral bodies beyond the pedicles and irregularity of the vertebral end plates. Histologic changes seen on growth plate biopsy permit the diagnosis to be confirmed. The inheritance pattern appears to be autosomal-recessive.
Automatic implementation of precise grid screens: the four-corners method.

Crystallization trials can be designed as a systematic gradient of the concen­tration of key reagents and/or pH centered on the original conditions. While the concept of the grid screen is simple, its implementation is tedious and difficult by hand. A procedure has been developed for preparing crystallization grid screens that is both efficient and achieves high accuracy because it relies on a limited number of solutions that are carefully prepared by hand. The `four-corners' approach to designing grid screens uses the minimum and maximum concen­trations of the components being varied in the grid screen as the sole stock solutions. For an N-dimensional grid only 2N corner solutions require detailed preparation, making the screens efficient. Furthermore, by keeping the concentrations as tight as possible to the grid, the potential impact of pipette errors is minimized, creating a highly precise screen.
Coulomb Stress Transfer and Tectonic Loading Preceding the 2002 Denali Fault Earthquake

Pre-2002 tectonic loading and Coulomb stress transfer are modeled along the rupture zone of the M 7.9 Denali fault earthquake (dfe) and on adjacent segments of the right-lateral Denali–Totschunda fault system in central Alaska, using a three-dimensional boundary-element program. The segments modeled closely follow, for about 95°, the arc of a circle of radius 375 km centered on an inferred asperity near the northeastern end of the intersection of the Patton Bay fault with the Alaskan megathrust under Prince William Sound. The loading model includes slip of 6 mm/yr below 12 km along the fault system, consistent with rotation of the Wrangell block about the asperity at a rate of about 1°/m.y. as well as slip of the Pacific plate at 5 cm/yr at depth along the Fairweather–Queen Charlotte transform fault system and on the Alaska megathrust. The model is consistent with most available pre-2002 Global Positioning System (gps) displacement rate data. Coulomb stresses induced on the Denali–Totschunda fault system (locked above 12 km) by slip at depth and by transfer from the M 9.2 Prince William Sound earthquake of 1964 dominated the changing Coulomb stress distribution along the fault. The combination of loading (∼70–85%) and coseismic stress transfer from the great 1964 earthquake (∼15–30%) were the principal post-1900 stress factors building toward strike-slip failure of the northern Denali and Totschunda segments in the M 7.9 earthquake of November 2002. Postseismic stresses transferred from the 1964 earthquake may also have been a significant factor. The M 7.2–7.4 Delta River earthquake of 1912 (Carver et al. , 2004) may have delayed or advanced the timing of the dfe, depending on the details and location of its rupture. The initial subevent of the 2002 dfe earthquake was on the 40-km Susitna Glacier thrust fault at the western end of the Denali fault rupture. The Coulomb stress transferred from the 1964 earthquake moved the Susitna Glacier thrust fault uniformly away from thrust failure by about 100 kPa. The initiation of the Denali fault earthquake was advanced by transfer of 30–50 kPa of positive Coulomb stress to the Susitna Glacier fault (Anderson and Ji, 2003) by the nearby M 6.7 Nenana Mountain foreshock of 23 October 2002. The regional tectonic loading model used here suggests that the Semidi (Alaska Peninsula) segment of the megathrust that ruptured in 1938 ( M 8.2) may be reloaded and approaching failure.
Dilepton production by protons on nuclei and the partonic origin of depletion at small momentum fraction

We discuss and extend our previous predictions of dilepton depletion at small target parton momentum fraction in proton-nucleus collisions. These predictions were based on an analysis of the partonic origin of the European Muon Collaboration effect in deep-inelastic scattering (DIS) in a treatment of nuclei allowing multiquark clusters to be formed. With this input, we calculate the ratio of dimuons produced on nuclei to those produced on free nucleons. We obtain excellent agreement with data from a recent experiment, emphasizing that all input information came from our previous DIS analysis. Our calculations predict that beyond the range of presently measured data, there will be considerable dependence on the momentum carried by the annihilating parton in the incident proton.
Machine Tools Mechatronic Analysis

High-speed machine tools show close interaction between the dynamic behaviour of the mechanical structure, drives, and numerical control. In order to support the designer of high-performance machines, a new analysis based on an integrated holistic mechatronic optimization technique is proposed and compared with the traditional approach. The proposed approach is applied to a three-axis milling machine for dies and mould production.
An Empirical Light Intensity Relationship for Elemental Mercury Emissions

Mercury in both its elemental and compound forms is an important environmental trace contaminant. One method of determining the concentration of mercury involves the application of atomic emission spectrometric principles. Most practical analytical applications are devoted to the construction of empirical growth curves (i.e., analytical signal vs concentration). The concentration of an unknown is then determined by interpolation. Ideally, at very low concentrations the signal will be found to be linearly related to the ground state concentration of the atoms which give rise to the signal. At higher atomic concentrations, the relationship becomes complex.
An analysis of dag-consistent distributed shared-memory algorithms

In this paper, we analyze the performance of parallel multithreaded algorithms that use dag-consistent distributed shared memory. Specifically, we analyze execution time, page faults, and space requirements for multithreaded algorithms executed by a workstealing thread scheduler and the BACKER algorithm for maintaining dag consistency. We prove that if the accesses to the backing store are random and independent (the BACKER algorithm actually uses hashing), the expected execution time TP(C) of a “fully strict” multithreaded computation on P processors, each with a LRU cache of C pages, is O(T1(C)=P+mCT∞), where T1(C) is the total work of the computation including page faults, T∞ is its critical-path length excluding page faults, and m is the minimum page transfer time. As a corollary to this theorem, we show that the expected number FP(C) of page faults incurred by a computation executed on P processors can be related to the number F1(C) of serial page faults by the formula FP(C) F1(C)+O(CPT∞). Finally, we give simple bounds on the number of page faults and the space requirements for “regular” divide-and-conquer algorithms. We use these bounds to analyze parallel multithreaded algorithms for matrix multiplication and LU-decomposition.
Orthogonality properties of modes in a compressible partially ionized plasma

Linearized hydrodynamic equations together with Maxwell’s equations are used to describe a compressible partially ionized plasma interacting with a weak electromagnetic field. Using this fluid description of a plasma, orthogonality properties of modes are investigated for a compressible, partially ionized plasma. This plasma is confined in a uniform cylindrical structure of arbitrary cross-section, in the presence or absence of a static magnetic field along the axial direction.