cssi/SciSciGPT-SciSciNet huggingface dataset:
Organochlorine compounds and testicular dysgenesis syndrome: human data.

Cryptorchidism, hypospadias, subfertility, and testicular germ-cell tumor have been suggested to comprise a testicular dysgenesis syndrome (TDS) based on the premise that each may derive from perturbations of embryonal programming and gonadal development during fetal life. Endocrine-disrupting chemicals have been hypothesized to be associated with these disorders given the importance of sex steroid hormones in urogenital development and homeostasis. Organochlorines are one such set of compounds which are defined as containing between one and ten covalently bonded chlorine atoms. These compounds are persistent pollutants with long half-lives, accumulate in adipose tissue when ingested, bioaccumulate and biomagnify, and have complex and variable toxicological profiles. Examples of organochlorines include dichlorodiphenyltrichloroethane (DDT) and its metabolites, polychlorinated biphenyls (PCBs) and chlordane. In this comprehensive review of human epidemiologic studies which have tested for associations between organochlorines and facets of TDS, we find evidence for associations between the exposures p,p′-DDE, cis-nonachlor, and trans-nonachlor with TGCT. The sum of the evidence from human epidemiologic studies does not indicate any association between specific organochlorines studied and cryptorchidism, hypospadias, or fertility. Many other endocrine-disrupting chemicals, including additional organochlorines, have yet to be assessed in relation to disorders associated with TDS, yet study of such chemicals has strong scientific merit given the relevance of such hypotheses to urogenital development.
The activity platform

In this paper, we advocate "activity" to be a central abstraction between people and computing instead of applications. We outline the vision of the activity platform as the next-generation social platform.
Response to Drought Stress of Nitrogen Fixation (Acetylene Reduction) Rates by Field-Grown Soybeans

The effects of drought stress on soybean nodule conductance and the maximum rate of acetylene reduction were studied with in situ experiments performed during two seasons and under differing field conditions. In both years drought resulted in decreased nodule conductances which could be detected as early as three days after water was withheld. The maximum rate of acetylene reduction was also decreased by drought and was highly correlated with nodule conductance (r = 0.95). Since nodule conductance is equal to the nodule surface area times the permeability, the relationship of these variables to both whole-plant and unit-nodule nitrogenase activity was explored. Drought stress resulted in a decrease in nodule gas permeability followed by decreases in nodule surface area when drought was prolonged. Under all conditions studied acetylene reduction on a unit-nodule surface area basis was highly correlated with nodule gas permeability (r = 0.92). A short-term oxygen enrichment study demonstrated nodule gas permeability may limit oxygen flux into both drought-stressed and well-watered nodules of these field-grown soybeans.
Ski inhibits TGF-β/phospho-Smad3 signaling and accelerates hypertrophic differentiation in chondrocytes.

Since TGF-β/Smad signaling inhibits chondrocyte maturation, endogenous negative regulators of TGF-β signaling are likely also important regulators of the chondrocyte differentiation process. One such negative regulator, Ski, is an oncoprotein that is known to inhibit TGF-β/Smad3 signaling via its interaction with phospho-Smad3 and recruitment of histone deacetylases (HDACs) to the DNA binding complex. Based on this, we hypothesized that Ski inhibits TGF-β signaling and accelerates maturation in chondrocytes via recruitment of HDACs to transcriptional complexes containing Smads. We tested this hypothesis in chick upper sternal chondrocytes (USCs), where gain and loss of Ski expression experiments were performed. Over-expression of Ski not only reversed the inhibitory effect of TGF-β on the expression of hypertrophic marker genes such as type × collagen (colX) and osteocalcin, it induced these genes basally as well. Conversely, knockdown of Ski by RNA interference led to a reduction of colX and osteocalcin expression under basal conditions. Furthermore, Ski blocked TGF-β induction of cyclinD1 and caused a basal up-regulation of Runx2, consistent with the observed acceleration of hypertrophy. Regarding mechanism, not only does Ski associate with phospho-Smad2 and 3, but its association with phospho-Smad3 is required for recruitment of HDAC4 and 5. Implicating this recruitment of HDACs in the phenotypic effects of Ski in chondrocytes, the HDAC inhibitor SAHA reversed the up-regulation of colX and osteocalcin in Ski over-expressing cells. These results suggest that inhibition of TGF-β signaling by Ski, which involves its association with phospho-Smad3 and recruitment of HDAC4 and 5, leads to accelerated chondrocyte differentiation.
A Qualia Representation of Cyberspace

E.C Adam defined Situational Awareness (SA) as "the mental representation and understanding of objects, events, people, system states, interactions, environmental conditions, and other situation-specific factors affecting human performance in complex and dynamic tasks. Stated in lay terms, SA is simply knowing what is going on so you can figure out what to do." We propose a novel idea to assist the human in gaining SA. Our hypothesis is that nature uses qualia as a compression scheme to represent the many concepts encountered in everyday life. Qualia enable humans to quickly come up with SA based on many complex measurements from their sensors, (eyes, ears, taste, touch, memory, etc.), expectations, and experiences. Our ultimate objective is to develop a computer that uses qualia concepts to transform sensor data to assist the human in gaining and maintaining improved SA. However, before any computer can use qualia, we must first define a representation for qualia that can be implemented computationally. This paper will present our representation for qualia. The representation is not simply a hierarchical aggregation of input data. Instead, it is a prediction of what will happen next, derived from computations resulting from sensory inputs and the computational engine of a qualia generator and qualia processor.
Schumpeter's ghost: Is hypercompetition making the best of times shorter?

At the center of Schumpeter's theory of competitive behavior is the assertion that competitive advantage will become increasingly more difficult to sustain in a wide range of industries. More recently, this assertion has resurfaced in the notion of hypercompetition. This research examines two large longitudinal samples of firms to discover which industries, if any, exhibit performance that is consonant with Schumpeterian theory and the assertions of hypercompetition. We find support for the argument that over time competitive advantage has become significantly harder to sustain and, further, that the phenomenon is limited neither to high-technology industries nor to manufacturing industries but is seen across a broad range of industries. We also find evidence that sustained competitive advantage is increasingly a matter not of a single advantage maintained over time but more a matter of concatenating over time a sequence of advantages. Copyright © 2005 John Wiley & Sons, Ltd.
The declining job satisfaction of white-collar women in sex-segregated and mixed-sex occupations

Abstract The declining job satisfaction of women white-collar workers reported by J. Veroff, E. Douvan, and R. A. Kulka (1981, The Inner American: A self-portrait from 1957 to 1976 , New York, Basic Books) is explored through secondary analyses of their data from two national cross-sectional surveys conducted in 1957 and 1976. Analyses were done using data from 258 women in 1957 and 372 women in 1976 in white-collar jobs. Multivariate contingency table analyses were used first to explore the separate effects of type of white-collar employment, whether or not the job was sex segregated, age, birth cohort, and education on job satisfaction declines. The decline in job satisfaction was found to be greater for women in sex-segregated occupations that in mixed-sex ones. In addition, while all white-collar women express increased dissatisfaction with ego-involving aspects of work, those in sex-segregated fields showed the greatest increases in job dissatisfactions in affiliative and achievement spheres. Neither type of white-collar employment nor birth cohort related to differential job satisfaction declines though age and education changes did. The final multivariate analysis demonstrated that the changing age and educational characteristics of job holders in sex-segregated fields accounted for the greater job satisfaction declines for these women, and that sex segregation did not appear to affect job satisfaction beyond changes related to these demographic factors.
Rate of oxygen effect reactions in irradiated barley seeds

Abstract The influence of concentrations of oxygen and radiation-induced oxygen sensitive sites on their rates of reactions in barley seeds was investigated. Himalaya (C.I. 620) barley seeds were adjusted to 9.9% water content irradiated with 60 Co gamma rays and soaked at 0°C in distilled water bubbled with oxygen and nitrogen gas mixtures containing 0.0, 12.5, 25, 50 and 100% oxygen. Treatment effects were measured as M 1 seedling injury. In one experiment, irradiated seeds were initially soaked in oxygen-saturate water, then transferred to O 2 -free water (nitrogen soaking) at selected time intervals. An increase in oxygen enhancement (OE) as measured by seedling injury is obtained with increased O 2 -soaking duration. A measure of the reaction rate between O 2 and O 2 -sensitive sites (OSS) is thus obtained. This reaction is radiation exposure dependent. A reverse experiment (initial nitrogen soaking with transfer to O 2 soaking at selected intervals) gives a measure of the lifetime of the OSS in water (quenching reaction). The same experimental plan is followed in two other experiments where the oxygen concentration in the gas phase of the soaking solution (OC) is variable. These experiments provide a measure of the influence of OC on the OE and OSS quenching reactions. A single radiation exposure was used. These results are demonstrated in four figures and numerical results and “reaction rates” are in two tables. The quenching reactions were independent of radiation exposure and OC. At low to intermediate OC the quenching reactions terminated the O 2 -OSS reaction. At 100% OC the O 2 -OSS reaction was two to three times faster and started three times sooner than the quenching reaction.
Suicide attempts, substance abuse, and personality

The prevalence and relevance of a positive suicide attempt history among 103 subjects who had entered a substance abuse program and participated in a study of personality was examined. Twenty subjects had a positive suicide attempt history. Women were more likely to attempt suicide. Attempters were more likely to have additional psychiatric diagnoses, such as major depression. Attempters had higher addiction severity scores, abused more substances, and were more likely to have abused alcohol and sedative hypnotics than were nonattempters. DSM-III-R and Eysenck personality measures were compared across groups. Attempters had significantly higher neuroticism and borderline scores. Impulse dysregulation may predispose this group to more severe addictions.
Alpha Inflation? The Impact of Eliminating Scale Items on Cronbach's Alpha

In this paper, we study the effect of the elimination of items from a scale so that only those items that correlate highly are chosen. Using a simulation, we estimate the impact on Cronbach's alpha as a function of the total number of items in a scale, the number of items chosen, the true correlation among the items, and the sample size. The results suggest that a substantial effect can exist. Not surprisingly, the effect is larger when sample sizes are smaller, when a smaller fraction of the original items is retained, and when there is greater variation in the true item-total correlations of the measures.
Spontaneous conversion to estrogen receptor expression by the human breast epithelial cell line, MCF-10A.

The human breast epithelial cell line, MCF-10A, derived from tissue from a woman undergoing a cutaneous mastectomy for fibrocystic breast disease, is negative for estrogen receptor expression, has undergone minimal genetic changes, retains many of the characteristics of normal breast epithelium and fails to exhibit growth in nude mice. When transfected with a functional copy of the estrogen receptor, both ER and MDM2 expression are negatively regulated by the presence of increasing concentrations of estradiol, as previously reported. We obtained the MCF-10A cell line from the American Type Culture Collection and confirmed that it was negative for ER expression. After approximately 20 passages under differing growth conditions, one sublime was determined to be positive for ER expression. Growth of this ER-positive sublime in phenol red-free media supplemented with charcoal-dextran stripped serum in the presence of nanomolar concentrations of estradiol failed to modulate ER and MDM2 expression, and induced expression of both pS2 and cathepsin D. Simultaneously with these observations, we observed that this subline, unlike the parent MCF-10A line, overexpressed P53 protein with a nuclear localization. Intermediate levels of the P53-inducible protein p21 WAF1/Cip1 were also detected in the ER-positive sublime whereas levels of this protein in the parent sublime were barely detectable, as measured by immunohistochemical methods. We conclude from these studies that ER expression and P53 alteration may constitute early steps in progression of malignant potential for breast cancer development.
On the intracellular uptake of neuraminidase

Abstract The intracellular uptake of neuraminidase by three different cell types was studied by two independent methods: (1) measurement of the electrophoretic mobility of nuclei isolated from cells with or without previous neuraminidase treatment and (2) direct observation by fluorescence microscopy of the uptake of fluorescein iso-thiocyanate labelled neuraminidase. The results indicate that neuraminidase can enter these cells and release intracellular N-acetylneuraminic acid. It is thus possible to account for the observed discrepancy between the amount of sialic acid released from cells and the observed drop in surface charge density.
SURFACE FORCES IN COLLOIDAL PROCESSING WITH NANO-PARTICLES

Surface forces acting between particles and different contributions to the forces are outlined with particular attention paid to the colloidal stability with nanosize particles. This is followed by a discussion of surface forces for nanosize particles and an introduction of a novel nanosize colloidal probe technique in an atomic force microscope.
Children's perceptions of relative competence in sex-typed occupations

Children ranging in age from 5 1/2 to 9 years old selected either a male or a female doll in response to questions about who would be “better” at an occupation. The occupations were selected so that half were female and half were male sex-typed occupations. The responses indicated that children have clear sex-typed expectations concerning occupational competence. While the differences between the “female” and “male” occupations were significant at each age level, the interaction revealed an increasing adherence to the stereotypes with increasing age. A sex of child main effect was produced by the tendency of female children to select the female doll more often than did male children. The results are interpreted as demonstrating that children's perceptions of these occupations reflect an evaluative bias and not simply a recognition of adult stereotypes or actual rates of employment in the positions.
Contemporary Encephalitis Lethargica: Phenotype, laboratory findings and treatment outcomes

Encephalitis lethargica (EL) is a CNS disorder that manifests with lethargy sleep cycle disturbances, extrapyramidal symptomatology, neuropsychiatric manifestations, ocular features and cardio-respiratory abnormalities. Although there have been no reported outbreaks of EL recently, a number of reports show that cases of EL are still encountered regularly. Against this background we conducted a study aiming to elucidate the clinical characteristics, describe laboratory/ neuroimaging findings (MRI, PET) and present treatment options and outcomes in sporadic EL. Patients were diagnosed over a period of 3 years using proposed diagnostic criteria. Extensive laboratory and imaging tests were performed for exclusion of other causes. Anti-neuronal antibodies against human basal ganglia were detected with western immunoblotting and 18F-FDG PET imaging was performed. Selected cases were videotaped. Our patients (M/F: 5/3) ranged from 2–28 years (mean 9.3 ± 9.5). Encephalopathy, sleep disturbances and extrapyramidal symptoms were present in all cases. Laboratory investigations revealed CSF leukocytosis in 5/8 patients and anti-BG Ab in 4/7 patients. MRIs revealed structural abnormalities in 7/8 cases. 18F-FDG PET showed basal ganglionic hypermetabolism in 4/7 patients. Treatment approaches included immunomodulating and symptomatic therapies. We report no mortality from EL in our series. There seems to be little doubt that cases of EL still occur. Diagnosis may be based on clinical suspicion and laboratory/imaging tests may lead to early initiation of immunomodulating and supporting therapies. We suggest that in addition to anti-BG Abs FDG PET should be considered as a diagnostic tool for EL.
Voluntary alteration of pattern visual evoked responses.

Abstract Pattern and flash visual evoked responses (VERs were recorded from a large group of ophthalmologically normal subjects during two conditions: in one they were instructed to attend to the stimulus and in the other they were instructed to ignore the stimulus but maintain their gaze on the stimulus. Pattern VERs were recorded from 42 subjects. Fixation was constantly monitored during both attend and ignore conditions and no changes of fixation were noted at any time. The amplitude of the major positive wave of the pattern VERs produced by both 50- and 25-min checks was reduced significantly during the ignore condition. The implicit time of this positive wave did not differ significantly during the two conditions. The pattern VERs of eight subjects were extinguished and the VERs of another three subjects were unrecognizable during the ignore condition. Flash VERs produced by 10 flashes per second were recorded from 38 of the 42 subjects. There were no significant differences between the amplitudes recorded during the attend and ignore conditions.
Is Gross Proteinuria a Risk Factor for the Incidence of Proliferative Diaberic Retinopathy

Purpose: To examine the relationship between gross proteinuria, measured at the initial examination, and the 4-year incidence of proliferative diabetic retinopathy (PDR) in a population-based study in Wisconsin. Methods: Gross proteinuria was measured by reagent strip. Diabetic retinopathy was determined from stereoscopic fundus photographs in a masked fashion using the modified Airlie House classification scheme. Results: In the younger-onset group taking insulin (n = 693), the relative risk of proliferative retinopathy developing in those with gross proteinuria at baseline was 2.32 (95% confidence interval [Cl]: 1.40,3.83) compared with those without gross proteinuria. For the older-onset group taking insulin, the relative risk was 2.02 (95% Cl: 0.91,4.44), and for those not taking insulin it was 1.13 (95% CI: 0. 15,8.50). After controlling for other risk variables, the relationship was of borderline statistical significance ( P = 0.052) in the younger-onset group with no or early non proliferative retinopathy at baseline. Conclusion: These data suggest that gross proteinuria is a risk indicator for proliferative retinopathy in younger-onset patients with diabetes. These patients might benefit from having regular ophthalmologic evaluation.
STRENGTH TRAINING IN OLDER WOMEN: EARLY AND LATE CHANGES IN WHOLE MUSCLE AND SINGLE CELLS

In order to examine the relative contribution of neural- and muscle-based adaptation to strength training, we studied early (2 weeks) and later (12 weeks) effects of strength training on muscle size and strength and type I single-fiber size and contractility in 14 elderly women (aged 68-79 years) and seven young controls. Older subjects were randomized to training (n = 7) or control (n = 7) groups. Strength did not change, but whole muscle size increased significantly after 2 weeks. After 12 weeks, strength, whole muscle size, and specific force all increased. No changes occurred in the control group. In single fibers, no changes in size and contractility were noted after 2 weeks, but specific force was higher in the training group after 12 weeks. Early adaptations to strength training in elderly women cannot be attributed to changes at the cellular level and therefore occur primarily in the central nervous system. Later, cellular adaptations in specific force track closely whole muscle changes.
Neuromotor deficits and mercury concentrations in rats exposed to methyl mercury and fish oil

It has been suggested that docosahexaenoic acid (DHA) or other n-3 polyunsaturated fatty acids (PUFAs) may prevent or ameliorate methyl mercury's neurotoxicity. To examine interactions between PUFAs and methyl mercury exposure, sixty-six female Long-Evans rats were exposed to methyl mercury continuously via drinking water from fifteen weeks of age. Water included methyl mercury concentrations of 0, 0.5, and 5.0 ppm, creating estimated intakes of about 0, 40, and 400 microg/kg/day across exposure groups. An additional fifty-eight female offspring were exposed to methyl mercury only during gestation. Rats consumed one of two diets, each based on AIN-93 formulation, providing a 2 (generation) X 2 (diet) X 3 (methyl mercury exposure) factorial experimental design. A "coconut oil" diet (1/3 of fats were provided by coconut oil) was marginally adequate in n-3 PUFAs and contained no DHA. A "fish oil" diet was rich in n-3 fatty acids, including DHA. The diets were approximately equal in n-6 fatty acids. Forelimb grip strength declined with age for all groups, but the decline was greatest for those exposed chronically to 400 microg/kg/day of methyl mercury. This high-dose group also displayed hind limb crossing, gait disorders, and diminished running wheel activity. Dietary n-3 fatty acids did not influence these effects. Chronic exposure to 400 microg/kg/day of methyl mercury resulted in blood and brain concentrations of about 70 and 10 ppm, respectively, approximately 50-fold higher than concentrations seen in rats exposed to 40 microg/kg/day. Rats that became ill and died before the experiment ended had higher concentrations of mercury than their cohorts who survived to the end. Organic mercury was highly correlated with total mercury in these rats but inorganic mercury remained approximately constant. Some deaths were due to urolithiasis (kidney or bladder stones) associated with a dietary contaminant and that was eventually fatal to 22% of the females in the colony. Neurobehavioral effects are reported on rats that did not become ill.
Trends in no leisure-time physical activity--United States, 1988-2010.

Purpose: The aim of this study was to examine trends in the prevalence of no leisure-time physical activity (LTPA) from 1988 to 2010. Method: Using the Behavioral Risk Factor Surveillance System data, 35 states and the District of Columbia reported information on no LTPA from 1988 to 1994; all states reported no LTPA from 1996 to 2010. Results: No LTPA significantly declined over two decades. Prevalence for all states declined on an average of 0.6% per year from 29.1% in 1996 to 24.1% in 2004 and stabilized from 2005 to 2010, ranging from 24.0% to 25.4%. Prevalence declined for both sexes and all racial/ethnic groups. Conclusion: While the no LTPA trends improved over two decades, one in four U.S. adults still report they do not engage in LTPA.
Personality in Extreme Situations: Thinking (or Not) under Acute Stress☆

Abstract To investigate the role of emotional experience and understanding in acute stress situations, the relations between three individual difference variables (clarity, attention, and intensity) and cognitive difficulties under acute stress were examined. Fifty-nine firefighter trainees completed personality measures several weeks before engaging in a series of four live-fire exercises. Individuals who were typically clear about their emotions (high clarity) reported fewer instances of cognitive difficulties, such as “blanking out” and being unable to think clearly during the exercises. Emotional intensity and attention to emotion were unrelated to reports of these symptoms.
Decision-Making Allowing for Uncertainty of Future Investment Opportunities

All capital investment decisions are made under varying degrees of risk and uncertainty. Evaluations of the desirability of capital investments require estimates of present conditions as well as forecasts of future events which involve these risks and uncertainties. Several recently developed models for capital investment decision-making have involved the random variable treatment of anticipated cash flows. When present worth calculations are made in these cases, a fixed interest rate is usually assumed. When internal rate of return calculations are made, the minimum acceptable rate of return is given a fixed value. This paper treats the minimum attractive rate of return used with present worth calculations and the minimum acceptable internal rate of return used with internal rate of return calculations as stochastic variables having subjective probability distributions. This procedure takes explicit account of the uncertainty of future investment opportunities. It is shown that, under certain circumstances, significant differences in the values of the mean and the variance of the criteria for making the investment decision are obtained when the results of this procedure are compared with results using the usual deterministic interest rate or minimum acceptable rate of return.
Effect of non-nitrogenous onium compounds on biliary excretion of procaine amide ethobromide☆

Non-nitrogenous onium compounds, such as methyltriphenylphosphonium, n-propyltriphenylphosphonium, hexane-1,6-bis(dimethylsulfonium), tetraphenylarsonium, and N[4(p-chlorophenoxy)-3-chloro] phenylacetamidotriphenylphosphonium, had little or no effect on the rate of biliary excretion of the quaternary amine procaine amine ethobromide (PAEB) in rats with ligated renal pedicles. Although methyltriphenylphosphonium depressed PAEB excretion slightly, the depressant effect was nonspecific, since the compound also depressed bile flow and the biliary excretion of an anionic drug.
Direct Nuclear Reactions Leading to Unbound Residual Nuclei

The distorted-wave matrix element for direct reactions leading to three-body final states is written in terms of convergent integrals. The resulting expression can be evaluated in the Butler approximation, which leads to a diffractive model of the competition of, and interference between, direct breakup and sequential decay reaction mechanisms. Using Amado's methods, I demonstrate the general presence of such interference in processes of interest. Moreover, it should be possible to normalize unstable-state spectroscopic factors by measuring this interference.
Charge Limits on Droplets during Evaporation

We have examined charge stability limits of single evaporating microdroplets that were suspended in an electrodynamic balance. A high precision light scattering technique based on optical resonances was used to determine the size and the size change of a droplet at a charge instability induced breakup. The charge level and the charge loss at the breakup were obtained from the dc voltages required to balance the droplet prior to and following the breakup. The results on droplets of diethyl phthalate (DEP), diethylene glycol (DEG), triethylene glycol (TEG), and hexadecane show that breakups due to the charge instability occur at the Rayleigh charge limit. The observed charge losses during breakups range from about 15.3% for hexadecane droplets to about 41.1% for TEG droplets. Hexadecane droplets lose about 1.5% of their mass, while DEP droplets, about 2.3%. Within the detectable limit of 0.03%, no mass losses were observed during breakups of DEG and TEG droplets. The observation of extremely low mass losses...
Drug intolerance to high-dose clarithromycin among elderly patients

Abstract We treated 13 elderly patients with chronic mycobacterial lung disease with clarithromycin using 1000mg b.i.d. as monotherapy. Patients had a mean age of 70 years, and 12 of 13 had creatinine clearances of 31–71 ml/min. Adverse events were seen in 100% of patients, with the most common being bitter taste (92%), nausea (92%), vomiting (54%) and central nervous system symptoms (54%). Elevated liver enzymes developed in five (38%) of 13 patients at weeks 1–6 of therapy. Mean serum levels of clarithromycin plus its 14-OH metabolite were 12.9 ± 3.6 μ g/ml (SD). There were 11 patients (85%) who discontinued the high dose within 3 months because of side effects. Serum drug levels of clarithromycin plus its 14-OH metabolite consistently exceeded 12 μg/ml in six of six patients who discontinued drug (10 of 10 values) compared with neither of two patients who tolerated the high dose (0 of 6 values). A dose reduction to 500mg b.i.d. was well tolerated (nine of 10 patients). Future trials with clarithromycin in this population should use lower doses with attention to body mass and renal function to minimize side effects.
The Political Ecology of Green Spaces in the City and Linkages to the Countryside

Political ecology is a concept with a mixed heritage. It has generally been applied to landscape level rural development questions such as soil erosion, deforestation and desertification, and quest...
Comparison of the immunochemical, receptor binding and biological properties of natural insulin-like growth factor I/Somatomedin C (IGF-I/Sm C) and its recombinant DNA-synthesized Thr-59 analog

We have synthesized a gene coding for an analog of TGF-I/Sm C and cloned it into a plasmid for expression in E. coli. This analog, containing Thr-59 and 8 extra amino acids at the N-terminal, was purified to homogeneity and tested for various activities. The 125I-labeled IGF-I analog has an affinity for Sm binding protein as well as antibodies raised against human-derived IGF-I that is slightly less than the natural molecule. Both 125I-labeled IGF-I and its analog bind to a specific cell membrane receptor on cultured human fibroblasts (HF) and rat chondrocytes (RC) in a time-, temperature-, and concentration-dependent manner. The analog stimulates the incorporation of 3H-thymidine into DNA in cultured RC and HF in a dose-response manner, with half-maximal stimulation at 12.5 and 62.5 ng/ml respectively, and is equipotent to natural IGF-I. In contrast, the Thr-59 analog did not enhance 35S-sulfate incorporation into chondroitin sulfate in RC in a fashion similar to the natural hormone. We conclude that this IGF-I analog has similar, though not identical, immunochemical, receptor binding and biological properties to human-derived IGF-I/Sm C. Nevertheless, we anticipate this peptide will be useful for studying the activity of this Sm.
Network-coded connected dominating set relaying for airborne tactical networks

In recent years, there's been a large push in the U.S. Department of Defense to provide greater bandwidth efficiency amidst congested spectrum. This is especially true in airborne tactical networks where transmit rates are limited and optimized for interference mitigation. Airborne tactical networks (ATNs) differ from many ground networks in that most of the traffic is broadcast and multicast. One method to more efficiently utilize the medium is to build a connected dominating set (CDS) backbone to reduce relay redundancy with overlapping nodes. While building a CDS has been shown to reduce retransmissions, thus saving bandwidth, backbone nodes can easily become congested. In this paper, we apply network coding to backbone CDS in airborne tactical networks to potentially mitigate the issues of congestion. Specifically, we implement network coded CDS (NCDS) in the Linux kernel and evaluate its performance compared to no coding under various relevant topologies. The results show that although NCDS can provide gains in tightly controlled topologies, the gains are severely limited in random and relevant ATN topologies.
A simple method for removal of AMP contamination from NADP+ for the assay of muscle fructose 1,6-bisphosphatase.

Abstract Muscle d -fructose 1,6-bisphosphatase 1-phosphohydrolase (Fru-P2ase) (EC 3.1.3.11) is extremely sensitive to inhibition by AMP, and even a trace contamination of this inhibitor in the assay mixture may result in a significant underestimation of the enzyme activity (1,2). Currently, Fru-P2ase activity is most commonly assayed by measuring the rate of NADP+ reduction in a coupling system (3). It was reported that commercial preparations of NADP+ contained varying amounts of AMP (4). Therefore, in the process of assaying muscle Fru-P2ase using NADP+, extreme care must be taken to ensure that the NADP+ used is free of AMP. The procedure for purification of NADP+ previously described by Horecker and Kornberg (5) has been successfully employed by some researchers to remove AMP from commercial NADP+ for the assay of muscle Fru-P2ase (2,6). In this paper we describe a much simpler method for the removal of contaminating AMP from commercial NADP+ for use in the assay of this muscle enzyme.
RESPIRATORY SYSTEM MECHANICAL BEHAVIOR IN THE CHICKEN

We evaluated whether the avian respiratory system displays the same fundamental mechanical behavior during external forcing as found in mammals. We measured airway flow and pressures in the trachea, air sacs and thoracoabdominal cavity in 4 anesthetized-paralyzed roosters during sinusoidal volume oscillations at the trachea in the normal range of euthermic breathing frequency, f(0.2 to 1.0 Hz), and tidal volume, VT (10-50 ml). From the pressure and flow waveforms, we calculated resistance (R) and elastance (E) of the total respiratory system and its major compartments (lungs, air sacs and chest wall). E of the chest wall was minimum (147 cmH2O.L-1 +/- 7 SE) at 0.2 Hz-50 ml and was consistently, slightly lower than E of the total respiratory system over the entire range studied. Both elastances showed the same dependence on f and VT, increasing slightly with increasing f and decreasing with increasing VT. R of the chest wall was maximum (35.6 cmH2O.L- 1.sec-1 +/- 2.2 SE) at 0.2 Hz-10 ml and decreased with increasing f and VT, although the VT effect diminished at the higher f. E and R of the air sacs were much smaller than those of the chest wall, but showed similar f and VT dependencies. R of the lungs, due to resistance of the airways, was minimum (6.8 cmH2O.L-1.sec-1 +/- 1.5 SE) at 0.2 Hz-10 ml and increased with both f and VT. Total respiratory R reflected R of the air sacs and chest wall at low f and R of the lungs at high f. The f and VT dependencies of E and R in the chicken were strikingly similar to those measured in various types of mammalian respiratory tissues (Stamenovic et al. (1990) J. Appl. Physiol. 69: 973-988. We conclude that, despite important anatomical differences between species, avian and mammalian respiratory tissues exhibit fundamentally similar mechanical behavior.
Temporal patterns and effects of perceived instructor compliance‐gaining use

This study examined student perceptions of instructor compliance‐gaining behavior and student affective and cognitive learning over a semester. Analysis of variance indicated significant differences among perceptions of instructor compliance‐gaining behavior at the beginning, middle, and end of the semester. Significant differences were also found in levels of student affective learning over the semester. Student perceptions of instructor compliance‐gaining significantly contributed to learning such that greater affective and cognitive learning was associated with less use of antisocial compliance‐gaining techniques and more use of prosocial techniques.
Concordance between molecular and phenotypic testing of Mycobacterium tuberculosis complex isolates for resistance to rifampin and isoniazid in the United States

Multidrug-resistant (MDR) isolates of Mycobacterium tuberculosis complex (MTBC) are defined by resistance to at least rifampin (RMP) and isoniazid (INH). Rapid and accurate detection of multidrug resistance is essential for effective treatment and interruption of disease transmission of tuberculosis (TB). Overdiagnosis of MDR TB may result in treatment with second-line drugs that are more costly, less effective, and more poorly tolerated than first-line drugs. CDC offers rapid confirmation of MDR TB by the molecular detection of drug resistance (MDDR) for mutations associated with resistance to RMP and INH along with analysis for resistance to other first-line and second-line drugs. Simultaneously, CDC does growth-based phenotypic drug susceptibility testing (DST) by the indirect agar proportion method for a panel of first-line and second-line antituberculosis drugs. We reviewed discordance between molecular and phenotypic DST for INH and RMP for 285 isolates submitted as MTBC to CDC from September 2009 to February 2011. We compared CDC's results with those from the submitting public health laboratories (PHL). Concordances between molecular and phenotypic testing at CDC were 97.4% for RMP and 92.5% for INH resistance. Concordances between CDC's molecular testing and PHL DST results were 93.9% for RMP and 90.0% for INH. Overall concordance between CDC molecular and PHL DST results was 91.7% for RMP and INH collectively. Discordance was primarily attributable to the absence of known INH resistance mutations in isolates found to be INH resistant by DST and detection of mutations associated with low-level RMP resistance in isolates that were RMP susceptible by phenotypic DST. Both molecular and phenotypic test results should be considered for the diagnosis of MDR TB.
An analysis of trichloroethylene movement in groundwater at Castle Air Force base, California

Abstract A trichloroethylene (TCE) plume has been identified in the groundwater under a U.S. Air Force Base in the Central Valley of California. An areal, two-dimensional numerical solute transport model indicates that the movement of TCE due to advection, dispersion, and linear sorption is simulated over a 25-year historic period. The model is used in several ways: (1) to estimate the extent of the plume; (2) to confirm the likely sources of contamination as suggested by a soil organic vapor survey of the site; and (3) to make predictions about future movement of the plume. Despite the noisy and incomplete data set, the model reproduces the general trends in contamination at a number of observation wells. The analysis indicates that soil organic vapor monitoring is an effective tool for identifying contaminant source locations. Leaky sewer pipes and underground tanks are the indicated pathways for TCE to have entered the groundwater system. The chemical mass balance indicates that a total of about 100 gallons of TCE — a relatively small amount of organic solvent — has created the observed groundwater plume.
Nonuniform blood flow in the canine left ventricle

In order to investigate the relationship between coronary perfusion pressure and blood flow distribution in the left ventricle (LV), we measured myocardial blood flow in small regions using radioactive microspheres in six anesthetized, open-chest dogs. Mean coronary perfusion pressure (CPP) was controlled with a femoral artery to left main coronary artery shunt which included a pressurized, servo-controlled blood reservoir. In each dog, we measured flow in 192 regions of the LV free wall (mean weight per region = 206 +/- 38 mg) at different perfusion pressures. At CPP = 80 mm Hg, blood flow to individual regions varied fourfold (0.30 to 1.18 ml/min/g; relative dispersion (RD) = 21.8 +/- 2.3%). At CPP = 50 mm Hg, flow varied over sevenfold (0.08 to 0.60 ml/min/g; RD = 42.8 +/- 10%; P less than 0.01 vs 80 mm Hg). This relationship between flow variability and CPP was present within individual LV layers as well between layers and is much higher than the error associated with the microsphere technique. We conclude that blood flow to small regions of the LV is markedly nonuniform. This heterogeneity becomes more profound at lower CPP. These findings suggest that (1) global measurements of coronary flow must be interpreted with caution, and (2) even in hearts with normal coronary arteries some regions of the LV are more susceptible to ischemia than others. In addition, these findings may help explain the patchy nature of myocardial damage that occurs following periods of low coronary pressure or inadequate myocardial protection during cardiopulmonary bypass.
Examining the Relationships Between Resilience, Mental Health, and Academic Persistence in Undergraduate College Students

Abstract Objective: In this study, the relationships between measures of interpersonal resilience, intrapersonal resilience, and mental health were examined with respect to academic and social integration, key determinants of academic persistence. Participants: A sample (n = 605) of undergraduate students was recruited from 2 midwestern universities during the 2007–2008 academic year. Methods: Hierarchal (or sequential) regression analysis examined whether the inter- and intrapersonal resilience and mental health measures contributed to explaining variance in the response variables of university cumulative grade point average (GPA) and university sense of belonging. Results: The intrapersonal resilience factors contributed to explaining variance in cumulative GPA in addition to aptitude and achievement. Furthermore, there was a strong statistical correlation between the inter- and intrapersonal resilience factors and mental health. Conclusions: The demands in college are significant and there is a need fo...
Polarization in the Elastic Scattering of Protons from Carbon and Nitrogen

The polarization of protons elastically scattered from nitrogen and carbon has been measured using double-scattering techniques. The polarization was determined for nitrogen at a scattering angle of 48\ifmmode^\circ\else\textdegree\fi{} c.m. in the proton-energy interval 12.6 to 13.6 MeV. The polarization resulting from elastic proton scattering with nitrogen targets had a constant value of -0.60\ifmmode\pm\else\textpm\fi{}0.10 in the incident proton-energy interval 8.2 to 11.8 MeV. The polarization from carbon, however, varied markedly with energy at most scattering angles. [Example: $P({50\ifmmode^\circ\else\textdegree\fi{}}_{\mathrm{lab}},12.9 \mathrm{MeV})=\ensuremath{-}0.8$, $P(50\ifmmode^\circ\else\textdegree\fi{},13.2)=\ensuremath{-}0.4$, and $P(50\ifmmode^\circ\else\textdegree\fi{},13.5)=\ensuremath{-}0.7$.] At numerous angles between 20\ifmmode^\circ\else\textdegree\fi{} and 140\ifmmode^\circ\else\textdegree\fi{}, polarization measurements from carbon covered the range of energies from 12.8 to 13.4 MeV. The angular distributions of polarization (and cross section) are in general quite sensitive to small changes in energy; the 12.95- and 13.25-MeV angular distributions even differ in shape significantly for $\ensuremath{\theta}g90\ifmmode^\circ\else\textdegree\fi{}$. The energy-averaged (12.8- to 13.4-MeV) angular distribution for the polarization of protons scattered from carbon was compared with optical-model calculations.
Bacillus subtilis CheD is a chemoreceptor modification enzyme required for chemotaxis

The chemotaxis machinery of Bacillus subtilis is similar to that of the well characterized system of Escherichia coli. However, B. subtilis contains several chemotaxis genes not found in the E. coli genome, such as cheC and cheD, indicating that the B. subtilis chemotactic system is more complex. In B. subtilis, CheD is required for chemotaxis; the cheD mutant displays a tumbly phenotype, has abnormally methylated chemoreceptors, and responds poorly to most chemical stimuli. Homologs of B. subtilis CheD have been found in chemotaxis-like operons of a large number of bacteria and archaea, suggesting that CheD plays an important role in chemotactic sensory transduction for many organisms. However, the molecular function of CheD has remained unknown. In this study, we show that CheD catalyzes amide hydrolysis of specific glutaminyl side chains of the B. subtilis chemoreceptor McpA. In addition, we present evidence that CheD deamidates other B. subtilis chemoreceptors including McpB and McpC. Previously, deamidation of B. subtilis receptors was thought to be catalyzed by the CheB methylesterase, as is the case for E. coli receptors. Because cheD mutant cells do not respond to most chemoattractants, we conclude that deamidation by CheD is required for B. subtilis chemoreceptors to effectively transduce signals to the CheA kinase.
Targeted cancer therapy

Disruption of the normal regulation of cell-cycle progression and division lies at the heart of the events leading to cancer. Complex networks of regulatory factors, the tumour microenvironment and stress signals, such as those resulting from damaged DNA, dictate whether cancer cells proliferate or die. Recent progress in understanding the molecular changes that underlie cancer development offer the prospect of specifically targeting malfunctioning molecules and pathways to achieve more effective and rational cancer therapy.
Statistical, geochemical, and morphological analyses of stone line formation in Uganda

Abstract The resolution of conflicting fluvial (allochthonic erosion and deposition) and bioturbation (autochthonic faunal turbation) theories of stone line formation has important implications for tropical geomorphology—with the former indicating dynamic, punctuated landscape development and the latter implying relative landscape stability with ongoing moderate erosion. On a gentle hill in central Uganda, we quantitatively characterized and statistically modeled gravel distributions for 93 profiles. Elemental analysis of K, selected rare-earth elements (REE) and appropriate index elements were employed to test for compositional differences between soils above and saprolite below hilltop stone lines. We also excavated and carefully described four indicative profiles. The results of this study were difficult to reconcile with the bioturbation theory of stone line formation. Important findings included (i) the lack of a consistent gravel-free biomantle with a weak connection between biomantle thickness and stone-line depth, (ii) highly variable stone line depth with a strong inverse relationship between stone line depth and maximum gravel content, (iii) unweathered and rounded cobbles in a stone line over saprolite with angular, highly weathered quartz, and (iv) a statistically significant geochemical difference between soils and saprolites, with evidence of a less weathered surface mantle over more weathered saprolite. These findings indicated a sedimentary origin for soils at this site—even for what is presently a flat, geomorphically isolated hilltop. Evidence from this study and previous work on the geochemistry of this site [Geochim. Cosmochim. Acta 67 (2003) 2711] suggests that the contemporary hilltop once occupied a lower landscape position.
Solution of the solar-neutrino problem

Comparison of the results from the Kamiokande neutrino-electron scattering experiment with those from the chlorine experiment and with solar models shows that the explanation of the solar-neutrino problem probably requires physics beyond the standard electroweak model with zero neutrino masses. The experimental results, including the shape of the electron-recoil energy spectrum measured by Kamiokande, are in excellent agreement with a nonadiabatic solution of the Mikheyev-Smirnov-Wulfenstein effect, yielding a neutrino mass difference of \ensuremath{\Delta}${\mathit{m}}^{2}$=1\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}8}$ ${\mathrm{sin}}^{\mathrm{\ensuremath{-}}2}$${\mathrm{\ensuremath{\Theta}}}_{\mathit{V}}$ ${\mathrm{eV}}^{2}$.