cssi/SciSciGPT-SciSciNet huggingface dataset:
A Social Network Analysis of Online Engagement for College Students Traditionally Underrepresented in STEM

Little is known about the online learning behaviors of students traditionally underrepresented in STEM fields (i.e., UR-STEM students), as well as how those behaviors impact important learning outcomes. The present study examined the relationship between online discussion forum engagement and success for UR-STEM and non-UR-STEM students, using the Community of Inquiry (CoI) model as our theoretical framework. Social network analysis and nested regression models were used to explore how three different measures of forum engagement—1) total number of posts written, 2) number of help-seeking posts written and replied to, and 3) level of connectivity—were related to improvement (i.e., relative performance gains) for 70 undergraduate students enrolled in an online introductory STEM course. We found a significant positive relationship between help-seeking and improvement and nonsignificant effects of general posting and connectivity; these results held for UR-STEM and non-UR-STEM students alike. Our findings suggest that online help-seeking has benefits for course improvement beyond what can be predicted by posting alone and that one need not be well connected in a class network to achieve positive learning outcomes. Finally, UR-STEM students demonstrated greater grade improvement than their non-UR-STEM counterparts, which suggests that the online environment has the potential to combat barriers to success that disproportionately affect underrepresented students.
Co-evolution of Opinion and Social Tie Dynamics Towards Structural Balance.

In this paper, we propose co-evolution models for both dynamics of opinions (people's view on a particular topic) and dynamics of social appraisals (the approval or disapproval towards each other). Opinion dynamics and dynamics of signed networks, respectively, have been extensively studied. We propose a co-evolution model, where each vertex $i$ in the network has a current opinion vector $v_i$ and each edge $(i, j)$ has a weight $w_{ij}$ that models the relationship between $i, j$. The system evolves as the opinions and edge weights are updated over time by the following rules, Opinion Dynamics and Appraisal Dynamics. We are interested in characterizing the long-time behavior of the dynamic model -- i.e., whether edge weights evolve to have stable signs (positive or negative) and structural balance (the multiplication of weights on any triangle is non-negative) Our main theoretical result solves the above dynamic system with time-evolving opinions $V(t)=[v_1(t), \cdots, v_n(t)]$ and social tie weights $W(t)=[w_{ij}(t)]_{n\times n}$. For a generic initial opinion vector $V(0)$ and weight matrix $W(0)$, one of the two phenomena must occur at the limit. The first one is that both sign stability and structural balance (for any triangle with individual $i, j, k$, $w_{ij}w_{jk}w_{ki}\geq 0$) occur. In the special case that $V(0)$ is an eigenvector of $W(0)$, we are able to obtain the explicit solution to the co-evolution equation and give exact estimates on the blowup time and rate convergence. The second one is that all the opinions converge to $0$, i.e., $\lim_{t\rightarrow \infty}|V(t)|=0$.
The Insulinlike Growth Factor Receptors

Early studies on the binding kinetics of receptors that exhibit relatively high affinity for [125I]insulinlike growth factors(1) indicated that heterogeneous receptor populations resided in many cell types.(1–3) These receptor populations appeared to differ in their exact affinity for [125I]IGF-I versus [125I]IGF-II, and marked differences in the abundance of these receptor populations could be observed among various tissues. It was also apparent from binding kinetic measurements that [125I]IGF-I and [125I]IGF-II exhibited low but significant affinity for insulin receptors(4) and that conversely [125I]insulin could bind with low affinity to at least one population of IGF receptors. From these binding studies, it became clear that a family of receptors with cross-reacting affinities for insulin and the IGF’s existed in many cells, but the number of receptor types and their structural identity were unknown.
MODEL TESTS FOR PLASTIC RESPONSE OF LINED TUNNELS

Static isotropic and uniaxial strain loading tests were performed on models in a rock simulant having an unconfined compressive strength of about 4,300 psi (29.7 mn/m squared) and a friction angle of 33 degree. The liners consisted of direct-contact steel tubes of three different radius-to-thickness ratios (a/h'50, 25, 12.5). In the isotropic loading experiments, the load-deformation relationship for the liners was in good agreement with theoretical curves from an elastic-plastic analysis and showed substantial increase in strength with increasing liner thickness. At the higher loads, the a/h'50 and a/h'25 liners buckled, and the deformations became larger than predicted by the theory. The a/h'12.5 liner did not buckle, even at tunnel closures of 5%. Similar behavior was found in uniaxial strain loading experiments, but 30% to 50% less load was required to cause 5% tunnel closure than under isotropic loading.
Nanoparticle Contrast Agents for Computed Tomography: A Focus on Micelles

Computed tomography (CT) is an X-ray-based whole-body imaging technique that is widely used in medicine. Clinically approved contrast agents for CT are iodinated small molecules or barium suspensions. Over the past seven years there has been a great increase in the development of nanoparticles as CT contrast agents. Nanoparticles have several advantages over small molecule CT contrast agents, such as long blood-pool residence times and the potential for cell tracking and targeted imaging applications. Furthermore, there is a need for novel CT contrast agents, owing to the growing population of renally impaired patients and patients hypersensitive to iodinated contrast. Micelles and lipoproteins, a micelle-related class of nanoparticle, have notably been adapted as CT contrast agents. In this review we discuss the principles of CT image formation and the generation of CT contrast. We discuss the progress in developing nontargeted, targeted and cell tracking nanoparticle CT contrast agents. We feature agents based on micelles and used in conjunction with spectral CT. The large contrast agent doses needed will necessitate careful toxicology studies prior to clinical translation. However, the field has seen tremendous advances in the past decade and we expect many more advances to come in the next decade.
Minority and Nonminority Adjustment to College: Differences or Similarities?.

Using a model of retention, this study focused on minority and nonminority students' adjustment to college. Data were collected via mailed questionnaire from 799 freshmen at a residential, public research university in the Midwest. Path analysis was used to test the model. Results indicated that perceived quality had significant effects on intent to persist for minorities but not for nonminorities, and academic achievement had significant effects on intent to persist for nonminorities but not for minorities. Similarities between the two groups, however, clearly overshadowed differences. For instance, perceived racial discrimination exerted equivalent effects (although weak) on intent to persist for minorities and nonminorities.
Lessons from a canine model of compensatory lung growth

For over a century, canines have been used to study adaptation to surgical lung resection or pneumonectomy (PNX) that results in a quantifiable and reproducible loss of lung units. As reviewed by Schilling (1965), the first successful experimental pneumonectomies were performed in dogs and rabbits in 1881. By the early 1920s, it was appreciated that dogs can function normally with one remaining lung that increases in volume to fill the thoracic cavity (Andrus, 1923; Heuer and Andrus, 1922; Heuer and Dunn, 1920); these pioneering observations paved the way for surgeons to perform major lung resection in patients. Reports in the 1950s (Schilling et al., 1956) detail surprisingly well-preserved work performance in dogs following staged resection of up to 70% of lung mass. Since then, the bulk of the literature on post-PNX adaptation has shifted to rodents, especially for defining molecular mediators of compensatory lung growth. Because rodents are smaller and easier to handle, more animals can be studied over a shorter duration, resulting in time and cost savings. On the other hand, key aspects of lung anatomy, development, and time course of response in the rodent do not mimic those in the human subject, and few rodent studies have related structural adaptation to functional consequences. In larger mammals, anatomical lung development more closely resembles that in humans, and physiological function can be readily measured. Because dogs are natural athletes, functional limits of compensation can be characterized relatively easily by stressing oxygen transport at peak exercise. Thus, the canine model remains useful for relating structure to function, defining sources and limits of adaptation as well as evaluating therapeutic manipulation. This chapter summarizes key concepts of compensatory lung growth that have been consolidated from canine studies: (i) structure-function relationships during adaptation, (ii) dysanaptic (unequal) nature of compensation, and (iii) signals for initiation of cellular growth.
Opportunistic mycotic infections in pregnant women

Abstract Immunosuppression was the major factor associated with the deaths of 44 women who died from opportunistic mycotic infections. The patients were immunosuppressed by malignancies, irradiation, cytotoxic drugs, and metabolic diseases. An additional four patients may have developed candidiasis as a result of antibiotic therapy. Coccidioidomycosis was the only mycosis solely associated with pregnancies not altered by exogenous immunosuppression.
Is Supreme Court Justice Antonin Scalia a Homophobe

Based exclusively on data from the official reports of the United States Supreme Court and the Massachusetts Supreme Judicial Court, this essay provides an empirical answer to the question: Is Supreme Court Justice Antonin Scalia a Homophobe?
Insect Pests of Rice

Rice is the most important food for mankind. Annual world rice production amounts to approximately 460 million tons grown on roughly 145 million ha (Norton and Way 1990). Over 90% of this area lies in Asia, while the remainder is divided among Latin America, Africa, Australia, Europe, and the United States (IRRI 1989). To keep pace with projected human population growth, rice production must increase from the 1987 levels to 20% more by 2000 and 65% more by 2020 (IRRI 1989). However, over 800 insect species attack standing and stored rice (Grist and Lever 1969). According to Pathak and Dhaliwal (1981) these pests account for rice losses of 24% while Cramer (1967) reports 35%. The importance of rice insect pests can be grasped by the fact that $910 million are spent annually in attempts to control their activities with insecticides (Woodburn 1990). Japanese rice farmers spend the most ($455 million), while farmers in developing countries spend much less per unit of production (Woodburn 1990). Furthermore, the value of insecticides applied to rice in 1988 was 15% of the total world usage of insecticides (Woodburn 1990). Thus, insect pests are serious enemies to rice production which must be protected and increased to foster human health and world peace and stability.
Is the third generation EGFR TKIs the solution for making EGFR mutant NSCLC a curable disease

Much promise and encouragement has been linked to the treatment of patients with advanced NSCLC harboring EGFR mutations. The first generation EGFR TKIs (e.g., erlotinib/gefitinib) gave promise as single agent therapy in the first-line setting (1). The second generation EGFR TKI with covalent irreversible binding to the receptor and with the potential to target heterodimers of the Erb-B receptors gave further promise regarding response, progressionfree survival and overall survival, particularly in patients with exon 19 deletions (2-4).
Detection of 1,2,4-benzenetriol induced aneuploidy and microtubule disruption by fluorescence in situ hybridization and immunocytochemistry

Abstract Fluorescence in situ hybridization (FISH) is becoming increasingly used to detect chromosomal changes in cancer cytogenetics. Here, we report its use in human HL60 cells to detect aneuploidy induced by the benzene metabolite, 1,2,4-benzenetriol (BT). Human centromeric probes specific for chromosomes 9 and 7 were used. Untreated HL60 cells were 0.72 ± 0.29% hyperdiploid for chromosome 9. Treatment with 5 μM BT increased this level 3-fold to 2.20 ± 0.87% and 50 μM increased it 4-fold to 2.96 ± 0.74%. Similar results were obtained with the chromosome 7 probe. The induction of aneuploidy by BT is therefore not chromosome-specific nor is it artifactual. Immunocytochemical staining with anti-tubulin antibodies also showed that BT disrupted microtubule organization at these concentrations. Thus, mitotic spindle disruption probably plays an important role in BT-induced aneuploidy. Trisomy and not tetrasomy accounted for the majority of the hyperdiploidy induced by BT in the two C-group chromosomes 7 and 9. Since trisomy of C-group chromosomes is commonly observed in leukemia, BT-induced aneuploidy may be involved in benzene-induced leukemia.
Effects of Pineal Factors on the Action Potentials of Sympathetic Neurons

1. Neurons from rat superior cervical ganglia were grown in coculture with pineal cells. Action potentials of neurons in cocultures were 25% longer and were 25% greater in amplitude than those recorded from neurons grown in the presence of ganglionic nonneuronal cells alone. 2. Neurons showed an increase in action potential duration with increasing time in culture. This may have been related to the recovery of nonneuronal cell populations after an initial exposure to the antimitotic agent Ara-C. In cultures not initially exposed to Ara-C, a subsequent exposure after 7 days in culture resulted in a shortening of the action-potential duration. 3. Neuronal cultures were exposed to gel slabs containing the pineal indolamines, serotonin,N-acetylserotonin, and melatonin. Serotonin andN-acetylserotonin showed no effect on the neuronal action potentials at the concentrations tested. 4. Melatonin caused an increase in action-potential duration that was associated not with an increase in action-potential amplitude, but with a decrease in actionpotential rise rates. The effects of long-term exposure in melatonin appeared to be reversible in some cells but not in all. 5. Short-term effects of melatonin were observed in older cultures and in younger cultures after the cells were stimulated repeatedly. Older cultures also had higher levels of spontaneous activity. The dependence of the short-term effects of melatonin on electrical activity may suggest a role for melatonin as a neuromodulator.
Comparison of Protein Precipitants for the Determination of Free Amino Acids in Plasma

The present study was undertaken to select the most preferred deproteinizing agent for microbiological or chromatographic determination of free amino acids in plasma. The highest quantities of amino acids were obtained from samples treated with picric acid, ethanol or sulfosalicylic acid. It was also found from examining the recoveries of 14C-labeled amino acids added to plasma following treatment with picric acid, ethanol and sulfosalicylic acid that one kind of deproteinizing agent is not equally effective with all amino acids. Picric acid treatment gave the most reliable results for determination of amino acids except the basic amino acids, alanine and tryptophan. Sulfosalicylic acid was the most recommended deproteinizing agent for basic amino acids and ethanol was good for the assay of alanine and tryptophan. The response of d-amino acids to the deproteinizing agents tested was not always similar to that of their l-isomers.
Toxicity and Tissue Residues from Diphenylhydantoin Fed to Chickens

Within three experiments with broiler-type crossbred chickens, diphenlyhydantoin (DPH) was administered via the diet at levels ranging from 10 to 2500 mg./kg. Feed intake and body weight gain were adversely affected by levels of 100 mg./kg. or higher. A hemorrhagic syndrome occurred in 16 percent of the chickens fed 100-1000 mg./kg. and 33 percent of those fed 2500 mg./kg. Twenty percent of the chickens fed 1000 mg./kg. were anemic; none of those receiving 250 mg./kg. were anemic. Other toxic manifestations included neurological side effects of a lethargic stupor, excitability to a disturbance, or a characteristic condition referred to as "head under." Pair-feeding experiments revealed thatlowered feed intake was not responsible for any of the clinical signs. All of the toxicity signs were reversible in 3 to 4 weeks following withdrawal of DPH. Muscle samples contained 2.5 to 11.4 mcg. DPH/g. at drug levels of 1000 and 2500 mg. DPH/kg. diet. Dose-response curves revealed that plasma, adipose, kidney and liver had levels which were, respectively, 1.05, 1.51, 2.19, and 2.85 times those of muscle.
Global Brightness Temperature Spectra at High Wavenuinbers Utilizing Satellite Microwave Measurements

Abstract Satellite microwave brightness temperature (radiance) measurements represent weighted mean temperatures in a certain atmospheric layer. The high density of measurements along a polar-orbiting satellite track allows estimates of the brightness temperature variance spectrum at high meridional wavenumbers. Global data from the Nimbus 6 SCAMS microwave instrument sensitive to the 100–300 mb layer have been analyzed for 30 days in August 1975. The results reveal that the brightness temperature variance spectrum can be fit to the form km over the range k=22 to 59 (horizontal wavelengths 1800 to 700 km). Using 95% confidence intervals, the fit yields m = −3.1±0.3 These results appear to have significance for estimates of energy cascade between different motion scales in the very high wavenumber regime.
Optimal surgical treatment of breast cancer: implications for local control and survival.

Improvements in the local control of primary breast cancer have been shown to improve long-term survival. The role of surgical therapy in maximizing local control includes: appropriate patient selection for breast conservation; tumor resection with pathologically free margins; careful staging with sentinel node biopsy; appropriate use of axillary dissection; and meticulous surgical technique to achieve these goals. Each component of surgical therapy has the potential for maximizing local control, and therefore for extending survival. J. Surg. Oncol. 2010; 101:677-686. © 2010 Wiley-Liss, Inc.
Valve origin of the aortic incisura

Abstract The occurrence and magnitude of the incisura of the central aortic pressure were shown in 66 patients to depend on the functional state of the aortic valve. In normal subjects and children with congenital aortic stenosis (with thin flexible leaflets), the incisura ranged between 6 and 14 mm Hg. With aortic regurgitation, the incisura diminished as the severity of regurgitation increased. With calcific aortic stenosis, the incisura was smaller or absent. These observations imply a valve mechanism productive of the incisura. In vitro studies of human aortic valves confirmed these observations. Additional in vitro studies with high speed cinematography (2,000 frames/sec) of a stented normal porcine valve also showed that early diastolic stretch and recoil of the leaflets occurs. These results indicate that in the presence of a normal or diseased aortic valve the aortic incisura is produced primarily by valve distension or recoil, respectively. Distension and rebound of the aortic walls do not appear to contribute significantly in the presence of a normal or a diseased valve. Because acquired aortic valve disease affects the magnitude of the central aortic incisura, inspection of the incisura may be of ancillary value in evaluating the pathologic state of the aortic valve.
A statistical approach to the construction and analysis of isobolograms

Current statistical procedures used in the construction of isobolograms do not use recent advances in mathematical statistics. The variability in the experimental data is either ignored or incompletely accounted for in the analyses. The decision procedures currently used to characterize the type of interaction between two agents do not permit the determination of the level of statistical significance associated with a given conclusion. Furthermore, the often formidable sample size is not exploited in the current isobologram methodology. Statistical techniques exist that may be used to construct isobolograms and decision procedures with a reliable level of significance. An isobologram is a contour of constant response of the underlying dose-response surface. Consequently, response surface methods (RSM) are useful in the estimation and analysis of isobolograms. The interaction between ethanol and chloral hydrate in female ICR mice was evaluated using the RSM approach by fitting the logistic model to quantal...
Retention behavior of ions in high performance ion chromatography: III effect of the nature of the cation on anion retention

The affects of alkali metal cations on the retention behavior of halide ions has been investigated. In general, the retention times of the anions were found to decrease as the size of the metal ion increased, although an inversion was observed for the rubidium and cesium ions. A similar inversion has been reported for calculated anion polarizabilities.
Ocular tissues contain inhibitors of lymphocyte mitogenesis

A fraction of bovine vitreous extract is a potent inhibitor of mitogen induced lymphocyte proliferation in vitro. Proliferation of lymphocytes induced in culture by lipopolysaccharide was more sensitive to inhibition by this fraction than were cultures of lymphocytes stimulated by Concanavalin A. We were unable to demonstrate such activity in similarly prepared fractions of cornea and lens.
Relationship between runoff and soil losses with rainfall characteristics and long-term soil management practices in a hilly vineyard (Piedmont, NW Italy)

AbstractRunoff and soil losses caused by natural rainfall events were monitored over a 10-year observation period in three experimental vineyard plots located in Alto Monferrato, a vine-growing area in Piedmont (NW Italy). The plots are characterized by a slope of about 15% and a soil classified as Typic Ustorthents, fine-loamy, mixed, calcareous, mesic. Each of them was managed with a different inter-row soil management practice: conventional tillage (CT), reduced tillage (RT) and controlled grass cover (GC), respectively. The rainfall characteristics, runoff discharge and concentration of soil in the water were measured. More than 150 rainfall events producing runoff and 63 erosive events were recorded. The data set was elaborated to investigate the relationships between runoff and soil losses with rainfall amount, duration and intensity, and to evaluate the effects of soil management methods. The amounts of water and soil that ran off the vineyard in the study period varied according to the season, rai...
Arecoline-induced skin inflammation: irritant or allergic dermatitis?

Abstract A severe skin inflammatory reaction halted the development of a transdermal device to systemically deliver arecoline, a cholinergic agonist, for use in the management of a human neurological disorder. This report demonstrates that the skin reaction is most likely an allergic contact dermatitis (ACD) exacerbated by inflammation, as characterized by classical immunological tests employing inbred mice: abdominal skin sensitization followed by ear challenge and ear challenge of recipients of lymphoid tissues from previously sensitized donors. Chemical analysis of the parent compound in three vehicles was performed to determine the chemical stability of the prepared solutions and the antigen specificity of the murine ACD response. Arecoline was hydrolyzed to the pharmacologically inactive metabolite, arecaidine, to the greatest extent in aqueous vehicles. ACD reactions were greatest when mice were both topically sensitized and challenged with arecoline. In contrast, arecaidine, the hydrolyzed product, did not have immunological activity, but was capable of producing local inflammation in a dose-dependent manner upon subcutaneous injection. These data support the mechanistic hypothesis that upon absorption into skin, arecoline induces a local inflammatory response and a systemic ACD response. Influx of lymphocytes to an arecoline-treated skin site likely mediate ACD through the combined inflammation produced by arecoline and arecaidine and recognition of arecoline as an immunogen.
CAPITALIZATION OF URBAN TRAVEL IMPROVEMENTS INTO RESIDENTIAL AND COMMERCIAL REAL ESTATE: SIMULATIONS WITH A UNIFIED MODEL OF HOUSING, TRAVEL MODE AND SHOPPING CHOICES

. An equilibrium model of multimodal travel time improvements is developed and calibrated for the New York Metropolitan Area. The model employs a unified treatment of housing type, residential location and commuting mode choices with shopping (destination, frequency and mode) choices. Benefits of halving subway headways are reflected in consumer surplus and capitalized into producer surplus, with the latter divided between housing and commercial real estate. Sensitivity tests and simulations on other modes are also presented. Unlike the subway mode, across-the-board travel time improvements for bus, auto and commuter rail reduce central area housing rents, but auto improvements yield higher total benefits and increases in commercial rents.
Evaluation of processing alternatives to saw delintering of cottonseed

Results are presented on economic evaluations of several alternative processes to saw delintering. Comparisons were made in terms of yields and quality of products, and processing costs. Comparisons of net monetary returns per ton of seed, and discounted cash flow rates of return showed no alternative processes to be attractive with linters selling at $0.04/lb or above. However, at a break-even linters price of $0.03/lb, hulling of undelintered seed and dilute sulfuric acid delintering were quite attractive alternatives. Hulling of undelintered seed was likewise attractive because of low processing energy requirements and low atmospheric emissions and workroom dust and noise.
Optimal Workforce Mix in Service Systems with Two Types of Customers

We consider a service system with two types of customers. In such an environment, the servers can either be specialists (or dedicated) who serve a specific customer type, or generalists (or flexible) who serve either type of customers. Cross-trained workers are more flexible and help reduce system delay, but also contribute to increased service costs and reduced service efficiency. Our objective is to provide insights into the choice of an optimal workforce mix of flexible and dedicated servers. We assume Poisson arrivals and exponential service times, and use matrix-analytic methods to investigate the impact of various system parameters such as the number of servers, server utilization, and server efficiency on the choice of server mix. We develop guidelines for managers that would help them to decide whether they should be either at one of the extremes, i.e., total flexibility or total specialization, or some combination. If it is the latter, we offer an analytical tool to optimize the server mix.
Transcriptomics of differential vector competence: West Nile virus infection in two populations of Culex pipiens quinquefasciatus linked to ovary development.

Understanding mechanisms that contribute to viral dissemination in mosquito vectors will contribute to our ability to interfere with the transmission of viral pathogens that impact public health. The expression of genes in two Culex pipiens quinquefasciatus populations from Florida with known differences in vector competence to West Nile virus (WNV) were compared using high throughput sequencing. A total of 15,176 transcripts were combined for comparison of expression differences between the two populations and 118 transcripts were differentially expressed (p < 0.05). The fold change in expression of the differentially expressed genes ranged from -7.5 – 6.13. The more competent population for WNV (Gainesville) over expressed 77 genes and down regulated 44 genes, compared with the less competent population for WNV (Vero Beach). Also, splicing analysis identified 3 transcripts with significantly different splice forms between the two populations. The functional analysis showed that the largest proportion of transcripts was included in the catalytic activity and transporter activity groups except for those in the unknown group. Interestingly, the up- regulated gene set contained most of the catalytic activity function and the down- regulated gene set had a notable proportion of transcripts with transporter activity function. Immune response category was shown in only the down regulated gene set, although those represent a relatively small portion of the function. Several different vitellogenin genes were expressed differentially. Based on the RNAseq data analysis, ovary development was compared across the populations and following WNV infection. There were significant differences among the compared groups. This study suggests that ovary development is correlated to vector competence in two Culex populations in Florida. Both populations control energy allocations to reproduction as a response to WNV. This result provides novel insight into the defense mechanism used by Culex spp. mosquitoes against WNV.
Complementation analysis of the inorganic carbon concentrating mechanism of chlamydomonas reinhardtii

Six independently isolated mutants of Chlamydomonas reinhardtii that require elevated CO2 for photoautotrophic growth were tested by complementation analysis. These mutants are likely to be defective in some aspect of the algal concentrating mechanism for inorganic carbon as they exhibit CO2 fixation and inorganic carbon accumulation properties different from the wild-type. Four of the six mutants defined a single complementation group and appear to be defective in an intracellular carbonic anhydrase. The other two mutations represent two additional complementation groups.
Historical perspectives of The American Association for Thoracic Surgery: Alfred Blalock (1899-1964).

Great men are not a common occurrence. Indeed, they are a rare find. Though respected and lauded in their time, it is only in retrospect that their true contributions can be adequately measured as a surgeon, an educator and a scientist. Such is the case of Dr. Alfred Blalock. Many have considered him the father of modern cardiac surgery. All consider his “blue baby” operation to be one of the landmarks of cardiac surgery and, as the chief of surgery at Johns Hopkins, he trained many who would become the leaders of our discipline. His continual reach for excellence helped him to not only affect, but revolutionize the paradigm of surgical research, an understanding of the physiology of shock and the surgical management of pulmonic stenosis/atresia. Dr. Blalock was the 30th president of the American Association for Thoracic Surgery and his presidential address was given in 1951.
On a Schur-algorithm approach to spectral factorization: state-space formulae

Abstract In some earlier publications [10–13] we indicated how the classical Schur algorithm can be used as a method to solve a spectral factorization problem. In the present paper indicate how to obtain a state-space formulation of the theory and formulae for an iterative algorithm for spectral factorization using state-space representations.
Development of fly ash-based automotive brake lining

Abstract Coal-fired power plants all over the world generate huge amounts of fly ash each year, 70 million tons of which are produced in the United States alone. Only 40% of all fly ashes generated in the USA find beneficial applications and rest have to be disposed off, which is burden for the generation industry. Fly ash particles possess certain characteristics that make them suitable for use in friction composites as a filler material. An attempt has been made through this research to incorporate more than 50 wt% of fly ash particles in automotive brake lining friction composites. This paper presents the research carried out on development of friction composites, using fly ash obtained from a specific power plant in Illinois. Ingredients such as phenolic resin, aramid pulp, glass fiber, potassium titanate, graphite, aluminum fiber and copper powder were used in the composite development phase, in addition to the fly ash. The developed brake lining composites have exhibited consistent coefficients of friction in the range of 0.35–0.4, and wear rates lower than 12 wt%.
In vitro biotransformation of estradiol by explant cultures of murine mammary tissues.

In vivo experiments have demonstrated a correlation between the extent of 16 alpha-hydroxylation of estradiol and incidence of mammary cancer. The ability of mammary ductal epithelium (MDE), the site for neoplastic transformation, to metabolize estradiol or to accumulate estradiol metabolites has not been unequivocally established. Using a newly developed mammary explant culture system and a radiometric assay, we have compared the site-specific metabolism of estradiol (E2) by the C-17-oxidation and C-16 alpha-hydroxylation pathways in mouse tissues that differ in relative risk for mammary cancer. A comparison between MDE (target tissue) and liver (nontarget tissue) from NFS (low risk) and C3H/ouj (high risk) mice revealed that: a) increase in C-17-oxidation was similar in MDE and liver from the two strains, and b) while C-16 alpha-hydroxylation was similar in liver from the two strains (p = 0.5, n.s.), it was increased 4-fold in the MDE from the high risk C3H/ouj strain relative to that from the low risk NFS strain (p = 0.001). Furthermore, in vivo administration of progesterone resulted in modulation of cell proliferation as well as of E2 metabolism in mammary explant cultures. The effect of progesterone depended upon the presence of the MtV-2 proviral gene. This study demonstrates that mammary explants can extrahepatically metabolize estradiol. The specific risk-related increase in C-16 alpha-hydroxylation suggests that intrinsic metabolic ability of the target tissue leading to the formation of 16 alpha-hydroxyestrone from estradiol may be a determinant in the relative risk for developing mammary cancer.
SINGLE SHOT INTRAOPERATIVE EXCRETORY UROGRAPHY FOR THE IMMEDIATE EVALUATION OF RENAL TRAUMA

AbstractPurpose: We reviewed the quality and usefulness of single shot intraoperative excretory urography (IVP) for evaluating suspected upper urinary tract trauma at our trauma center.Materials and Methods: Between 1990 and 1997 single shot intraoperative IVP for staging renal injuries was performed in 50 patients in whom clinical instability major associated injuries mandated an intraoperative study. Contrast material (2 ml./kg.) was injected intravenously and images were obtained after 10 minutes. The quality and usefulness of each study were scored by a single attending urologist on a scale of 1-worst to 5-best.Results: Intraoperative study quality was generally good (average score 3.84). The information obtained was generally considered useful for determining urological treatment (average score 3.96). In 16 patients (32%) intraoperative IVP findings safely obviated renal exploration. No contrast medium reactions were noted and no complications developed that were attributable to intraoperative IVP.Co...
Microvillar cells of the olfactory epithelium: morphology and regeneration following exposure to toxic compounds

In recent years microvillar cells (MVC) have been identified in the olfactory epithelium of numerous species, including rodents, canines, and primates. However, there is no consensus on the morphologic or histochemical features of this cell, nor is the function of these cells currently known. Previous studies have examined MVC during development and in the mature olfactory epithelium, but not after toxic insult. A microvillar cell, defined by specific morphologic criteria, was studied in adult male Long-Evans rats exposed via inhalation to either 200 ppm methyl bromide for 4 h/day, 4 days/week for 2 weeks, or to 635 micrograms/m3 nickel for 6 h/day for 16 consecutive days, and sacrificed serially over several months. The pattern of recovery for MVC differed according to the severity and specificity of the insult to the olfactory epithelium. With methyl bromide, all cell types were completely depleted from olfactory epithelium immediately after injury, including MVC. MVC were slow to repopulate the epithelium, and appeared only when olfactory epithelium was complete in other respects. With nickel exposure, where the major effect was a gradual decrease in sustentacular cells with a thinning of the apical cytoplasm thickness, MVC showed a decline during exposure, but reappeared during recovery. In both cases, there was no difference in olfactory function, even when MVC were absent from the olfactory epithelium. A mature olfactory epithelium appears to be necessary to support the presence of this MVC, suggesting that it is not crucial to the regeneration processes or recovery of olfactory function, but perhaps plays some role, as yet undefined, in the unperturbed olfactory epithelium.
Resource-Seeking Agglomeration: A Study of Market Entry in the Lodging Industry

We analyze whether firms prefer collocating with incumbent firms when choosing among markets to enter, highlighting the role of resource-seeking as a motivation for collocation. We propose that entrants will locate near others possessing resources that can spill over, but will avoid locations where existing firms will exploit spillovers without contributing. To test these propositions, we analyze the location decisions of 570 new hotels in Texas between 1992 and 2000. We find that hotels are attracted to markets with branded upscale hotels. Further, we find that owners of upscale hotels avoid markets with hotels without similar resources. Copyright © 2004 John Wiley & Sons, Ltd.
Velocity and Momentum Decay Characteristics of a Submerged Viscoplastic Jet

Velocity and momentum decay characteristics of a submerged viscoplastic non-Newtonian jet are studied within the steady laminar flow regime. The governing mass and momentum conservation equations along with the Bingham rheological model are solved numerically using a finite-difference scheme. A parametric study is performed to reveal the influence of the initial velocity profile, flow inertia, and yield stress presence on the flow field characteristics. Two initial velocity profiles are considered, a top-hat and fully developed pipe jets. The centerline velocity decay is found to be more rapid for the pipe jet than the top-hat one when the fluid is Newtonian while the opposite trend is observed for yield stress Bingham fluids. The decay in the momentum flux of the pipe jet is always less than that of the top-hat jet. Momentum and velocity based jet depths of penetration are introduced and used to analyze the obtained flow field information for a wide range of Reynolds and yield numbers. Depths of penetration are found to linearly increase with the Reynolds number and substantially decrease with the yield number. The presence of yield stress significantly reduces the momentum and velocity penetration depths of submerged top-hat and pipe jets. Penetration depths of yield stress fluids are shown to be more than an order of magnitude smaller than the ones corresponding to Newtonian fluids.
An intricately patterned prefronto-caudate projection in the rhesus monkey

The distribution of prefronto-caudate fibers in the caudate nucleus was studied autoradiographically in monkeys of various ages in which tritiated amino acids had been injected into the middle one-third of the length of the dorsal bank of the principal sulcus. The results indicate that, contrary to previous reports which had suggested a projection to only the head of the caudate nucleus, area 9 of Brodmann projects to the entire length of the nucleus. In the head of the caudate nucleus the cortico-caudate fibers are distributed in a pattern which is remarkable in two respects. First, the grains are not uniformly distributed but rather are segregated into clusters separated from one another by territories in which grain density does not exceed background. Second, individual clusters of grains, circular or elliptical in shape, surround grain free cores. These patterns of fiber distribution within the head of the nucleus are more sharply defined in newborn than in older monkeys. Our findings suggest that the caudate nucleus is organized more as an anatomic and functional mosaic than as the homogeneously organized structure that it is commonly considered to be.
Screening of phenylpyruvic acid producers and optimization of culture conditions in bench scale bioreactors

Alpha keto acids are deaminated forms of amino acids that have received significant attention as feed and food additives in the agriculture and medical industries. To date, their production has been commonly performed at shake-flask scale with low product concentrations. In this study, production of phenylpyruvic acid (PPA), which is the alpha keto acid of phenylalanine was investigated. First, various microorganisms were screened to select the most efficient producer. Thereafter, growth parameters (temperature, pH, and aeration) were optimized in bench scale bioreactors to maximize both PPA and biomass concentration in bench scale bioreactors, using response surface methodology. Among the four different microorganisms evaluated, Proteus vulgaris was the most productive strain for PPA production. Optimum temperature, pH, and aeration conditions were determined as 34.5 °C, 5.12, and 0.5 vvm for PPA production, whereas 36.9 °C, pH 6.87, and 0.96 vvm for the biomass production. Under these optimum conditions, PPA concentration was enhanced to 1,054 mg/L, which was almost three times higher than shake-flask fermentation concentrations. Moreover, P. vulgaris biomass was produced at 3.25 g/L under optimum conditions. Overall, this study demonstrated that optimization of growth parameters improved PPA production in 1-L working volume bench-scale bioreactors compared to previous studies in the literature and was a first step to scale up the production to industrial production.
Two mathematical models for energy forecasting

Mathematical models are adopted in the present work for two types of energy fore-casting. The first type is the forecasting of displacement of one energy source by the other and the second one the forecasting of the future energy demand. Several examples of applications of those models are illustrated by using historical data collected from various sources. In many cases, forecasting by these models is quite acceptable, while in some other cases, trend projection by them is not. so satisfactory. This reveals the deficiency of the forecasting models currently available. Possibles improvement of these models for handling more complicated forecasting is suggested.
Phosphoinositides Influence Pathogen Surfing: EPEC Rights the SHIP

Tir, a translocated effector protein from enteropathogenic E. coli (EPEC), contains two phosphotyrosines that initiate cellular signaling cascades, leading to localized actin polymerization into pedestals. A recent study now shows that two additional tyrosines within Tir recruit the inositol phosphatase SHIP2 to generate a PI(3,4)P2-enriched membrane platform that stabilizes pedestal assembly.
Some Causes for Lightning Data Inaccuracies: The Case of Michigan

Based on records currently available, no complete knowledge exists of the number of casualties caused by lightning in the United States. The compilation of lightning casualty statistics is not a simple problem, and there are many unresolved issues relating to definitions, procedures, and primary data sources. The purposes of this research were to consider the extent of incorrect reporting for Michigan as a case study for the nation and to determine some of the causes of the problem. The study outlines the problem, pinpoints limitations of the data, and underscores areas where more careful and uniform procedures could provide more consistent statistics. Lightning-related deaths in the state were traced through Department of Public Health death certificates, and lightning injuries severe enough to cause hospitalization were examined through hospital discharge records. A comparison of these figures to Storm Data statistics has shown the extent of inconsistency in lightning catastrophes reported for Michigan....
The Importance of the Unplanned and Uncertainty in the Development of Outdoor Leaders

Kurt Hahn is credited with being the unofficial â€œfatherâ€ of adventure-based education (Miner, 1999). He deliberately utilized adventure to combat what he felt were the moral declines in society of the day, and in so doing achieved specific outcomes (Richards, 1999). Since those early days at the Salem and later Gordonstoun schools, adventure has been the vehicle used by many to reach desired outcomes. While outcomes can often be â€œguaranteed,â€ the means of reaching the outcomes cannot. While promoting Outward Bound, Willi Unsoeld would often address concerns regarding participation. â€œâ€˜I can't guarantee you or your son won't die,' he was notorious for telling parents bluntly, â€˜but I can guarantee you if you continue to stifle him, his soul will surely die.'â€ (Unsoeld as quoted by Raynolds, 2007, p. 91) Like Hahn, Unsoeld knew the benefits of adventure and the importance of uncertainty.
Physiological studies of the brain: Implications for science teaching

Physiological changes resulting from repeated, long-term stimulation have been observed in the brains of both humans and laboratory animals. It may be speculated that these changes are related to short-term and long-term memory processes. A physiologically based model for memory processing (PBMMP) can serve to explain the interrelations of various areas of the brain as they process new stimuli and recall past events. The model can also serve to explain many current principles of learning theory and serve as a foundation for developing new theories of learning based upon the physiology of the brain.
Distinct characteristics of signal transduction events by histamine-releasing factor/translationally controlled tumor protein (HRF/TCTP)–induced priming and activation of human basophils

We previously identified a negative correlation between histamine release to histamine releasing factor/translationally controlled tumor protein (HRF/TCTP) and protein levels of the Src homology 2 domain–containing inositol 5′ phosphatase (SHIP) in basophils. We have also demonstrated that HRF/TCTP primes basophils to release mediators. The purpose of this study was to begin characterization of signal transduction events directly induced by HRF/TCTP and to investigate these events when HRF/TCTP is used as a priming agent for human basophil histamine release. Highly purified human basophils were examined for surface expression of bound HRF/TCTP, changes in calcium, and phosphorylation of Akt, mitogen-activated protein kinase kinase (MEK), extracellular signal–regulated kinase (ERK), Syk, and FcϵRIγ. Results showed that basophils from all donors bound HRF/TCTP. There was a biphasic calcium response to HRF/TCTP, which corresponded to the magnitude of histamine release. Furthermore, those donors who have direct histamine release when exposed to HRF/TCTP (HRF/TCTP responder [HRF/TCTP-R] donors) have phosphorylation of Syk, Akt, MEK, and ERK. Remarkably, basophils from HRF/TCTP-nonresponder (HRF/TCTP-NR) donors do not show phosphorylation of these molecules. This finding is different from IL-3, which also primes basophils for histamine release, but does show phosphorylation of these events. We conclude that priming induced by HRF/TCTP is distinct from that induced by IL-3.
Quantitative high-throughput screening of osteoblast attachment, spreading, and proliferation on demixed polymer blend micropatterns.

Designing materials that regulate cell function in a desired manner is a major goal of biomaterials engineering. Challenges include the vast material property space to be explored, the complexity o...