cssi/SciSciGPT-SciSciNet huggingface dataset:
Differential effects of some natural compounds on the transdermal absorption and penetration of caffeine and salicylic acid

Many natural products have the potential to modulate the dermal penetration of topically applied drugs and chemicals. We studied the effect of five natural compounds (hydroxycitronellal, limonene 1,2-epoxide, terpinyl acetate, p-coumaric acid, transferrulic acid) and ethanol on the transdermal penetration of two marker drugs ((14)C-caffeine and (14)C-salicylic acid) in a flow through in vitro porcine skin diffusion system. The parameters of flux, permeability, diffusivity, and percent dose absorbed/retained were calculated and compared. The dermal absorption of (14)C-caffeine was significantly higher with terpinyl acetate and limonene 1,2-epoxide as compared to ethanol; while dermal absorption of (14)C-salicylic acid was significantly greater with hydroxycitronellal and limonene 1,2-epoxide as compared to ethanol. A 10-fold increase in flux and permeability of caffeine with terpinyl acetate was observed while limonene increased flux of caffeine by 4-fold and permeability by 3-fold. Hydroxycitronellal and limonene increased salicylic acid's flux and permeability over 2-fold. The other natural compounds tested did not produce statistically significant effects on dermal penetration parameters for both caffeine and salicylic acid (p≥0.05). These results emphasize the differential effects of natural substances on the transdermal penetration of hydrophilic (caffeine) and hydrophobic (salicylic acid) drugs.
On the nature of catalyst promotion by manganese in CO hydrogenation to oxygenates over RhMn/NaY

CO hydrogenation over Mn promoted Rh/NaY catalysts was studied at 10 bar and 250°C. Significant selectivity to oxygenates, mainly ethanol and ethyl acetate, was obtained after neutralizing the protons that are formed during reduction of Rh ions. Layered bed experiments show that protons act as sites catalyzing secondary reactions. Protons also convert Mn(OH)2 to Mn2+ ions; the catalysts with highest selectivity to oxygenates contain MnO particles and Rh clusters. The results suggest chemical interaction of adsorbates on Rhn clusters with those on MnO.
Promoting Postpartum Exercise: An Opportune Time for Change

IN BRIEF: The postpartum period is an ideal time for clinicians to promote the importance of physical fitness, help patients incorporate exercise into lifestyle changes, and encourage them to overcome barriers to exercise. New responsibilities, physical changes, and competing demands for time may make exercise seem impossible. By emphasizing weight control, stress reduction, and other benefits, clinicians can help new mothers establish healthy exercise goals for the rest of their lives.
Oscillating gradient measurements of water diffusion in normal and globally ischemic rat brain.

Oscillating gradients were used to probe the diffusion-time/frequency dependence of water diffusion in the gray matter of normal and globally ischemic rat brain. In terms of a conventional definition of diffusion time, the oscillating gradient measurements provided the apparent diffusion coefficient (ADC) of water with diffusion times between 9.75 ms and 375 micros, an order of magnitude shorter than previously studied in vivo. Over this range, ADCs increased as much as 24% in vivo and 50% postmortem, depending on the nature of the oscillating gradient waveform used. Novel waveforms were employed to sample narrow frequency bands of the so-called diffusion spectrum. This spectral description of ADC includes the effects of restriction and/or flow, and is independent of experimental parameters, such as diffusion time. The results in rat brain were found to be consistent with restricted diffusion and the known micro-anatomy of gray matter. Differences between normal and postmortem data were consistent with an increase in water restriction and/or a decrease in flow, and tentatively suggest that physical changes following the onset of ischemia occur on a scale of about 2 microm, similar to a typical cellular dimension in gray matter.
Bodies and Accumulation: Revisiting Labour in the ‘Production of Nature’

This commentary on Neil Smith's Uneven Development revisits his production of nature thesis and uses it as a jumping off point to explore how human bodies matter in contemporary capitalism. It argues that human bodies are increasingly subsumed within capitalism in ways that go beyond the roles of humans as labourers and purchasers of goods and services in a system of commodities producing commodities. Bodies are also treated as property, transportation and as conditions of production within circuits of capitalisms. Bodies also absorb the externalities and excesses of production and provide new spaces of accumulation in their degradation.
A Prototype Simulation Model of a Wilderness Area

The purpose of this paper is to describe a simulation model for wilderness use patterns and to illustrate its behaviour with a small hypothetical trail and camp network. The program was written in GPSSV. The model defines schedules for each party using a given area, executes that schedule and records the interactions between parties as they progress along their schedules. Experimentation with the model indicates that it will provide a viable informational tool for the analysis of alternative management policies for low-density or wilderness recreational areas.
Algorithms for computer-aided generative process planning

Process planning is the function within a manufacturing facility that establishes the machining processes and parameters to be used so as to convert a piece-part from its initial form to the final form predetermined on an engineering drawing. Computer-aided process planning (CAPP) has become a major focus of manufacturing automation as it forms the interface between computer-aided design (CAD) and computer-aided manufacturing (CAM). Issues in CAPP include part representation, process selection, alternative process-plan generation, intermediate surface and tolerance determination, and operation sequencing. This paper focuses on quantitative models for determining cutting dimensions and tolerances for intermediate surfaces, and on a heuristic for sequencing cutting operations.
Tracking Delays in Report Availability Caused by Incorrect Exam Status with Web-Based Issue Tracking: A Quality Initiative

Many radiology information systems (RIS) cannot accept a final report from a dictation reporting system before the exam has been completed in the RIS by a technologist. A radiologist can still render a report in a reporting system once images are available, but the RIS and ancillary systems may not get the results because of the study’s uncompleted status. This delay in completing the study caused an alarming number of delayed reports and was undetected by conventional RIS reporting techniques. We developed a Web-based reporting tool to monitor uncompleted exams and automatically page section supervisors when a report was being delayed by its incomplete status in the RIS. Institutional Review Board exemption was obtained. At four imaging centers, a Python script was developed to poll the dictation system every 10 min for exams in five different modalities that were signed by the radiologist but could not be sent to the RIS. This script logged the exams into an existing Web-based tracking tool using PHP and a MySQL database. The script also text-paged the modality supervisor. The script logged the time at which the report was finally sent, and statistics were aggregated onto a separate Web-based reporting tool. Over a 1-year period, the average number of uncompleted exams per month and time to problem resolution decreased at every imaging center and in almost every imaging modality. Automated feedback provides a vital link in improving technologist performance and patient care without assigning a human resource to manage report queues.
Chitosan-based nanoparticles for topical genetic immunization

Numerous studies have reported the prophylactic and therapeutic use of genetic vaccines for combating a variety of infectious diseases in animal models. Recent human clinical studies with the gene gun have validated the concept of direct targeting of dendritic cells (Langerhan's cells) in the viable epidermis of the skin. However, it is unclear whether the gene gun technology or other needle-free devices will become commercially viable. The objective of our studies was to investigate the topical application of chitosan-based nanoparticles containing plasmid DNA (pDNA) as a potential approach to genetic immunization. Two types of nanoparticles were investigated: (i) pDNA-condensed chitosan nanoparticles, and (ii) pDNA-coated on pre-formed cationic chitosan/carboxymethylcellulose (CMC) nanoparticles. These studies showed that both chitosan and a chitosan oligomer can complex CMC to form stable cationic nanoparticles for subsequent pDNA coating. Selected pDNA-coated nanoparticles (with pDNA up to 400 microg/ml) were stable to challenge with serum. Several different chitosan-based nanoparticles containing pDNA resulted in both detectable and quantifiable levels of luciferase expression in mouse skin 24 h after topical application, and significant antigen-specific IgG titer to expressed beta-galactosidase at 28 days.
Abstract 5278: Inhibition of tumor cell migration and metastasis by the GPR4 receptor

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC GPR4, a G protein-coupled receptor, has been shown to function as a proton sensor. Within tumor microenvironments, the interstitial acidic pH may activate GPR4 to regulate the behavior of tumor cells, blood vessels, and other cells. The expression of GPR4 is detected in some tumor cells, and it is the focus of this study to investigate the effects of acidosis/GPR4 signaling on tumor cell migration and metastasis. B16F10 melanoma cells and TRAMP-C1 prostate cancer cells, genetically engineered to overexpress GPR4 or the control vector, were subject to a series of cell motility assays. Transwell and wound closure assays were performed to examine cell migration, and it was observed that upon GPR4 activation in an acidic pH, cell migration was inhibited two to four fold in comparison to the vector control. These same trends were observed for invasion assays, in which Matrigel or a HUVEC endothelial monolayer was applied to the top of each transwell filter. To elucidate the molecular mechanism by which acidosis/GPR4 mediated motility inhibition occurs, G-LISA RhoA activation assays were used and it was observed that upon GPR4 activation in an acidic environment, the levels of activated RhoA, when compared to the vector control, were increased two and three fold. Furthermore, activation of Rho by its activator CN01 in B16F10 and TRAMP-C1 tumor cells recapitulated the acidosis/GPR4 induced motility inhibition phenotype, while inhibition of Rho reversed such phenotype. To examine the biological effects in vivo, B16F10 cells were injected into C57BL/6 female mice through tail veins. Pulmonary melanoma metastasis was inhibited by greater than 80% in GPR4 overexpressing B16F10 cells in comparison to the vector control. Upon treatment with the Rho activator CN01 in culture, the phenotype of the B16F10 vector cells paralleled that of the GPR4 overexpressing cells as metastasis was inhibited by more than 90%. These findings suggest that GPR4 activation by acidic pH plays a role in the inhibition of migration and invasion in B16F10 and TRAMP-C1 tumor cells, and the activation of Rho is at least partly responsible for this phenotype on the molecular level. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5278.
Effects of pollution on skin aging.

Every day, patients ask dermatologists for ways to prevent looking old because visible signs of aging are a major concern for many people. In support of such a notion, the current worldwide market for cosmetic and medical products devoted to the prevention and treatment of skin aging is $15 billion (Yarosh, 2008). Discussions of the prevention of skin aging typically focus on the role of sunlight and smoking because solar radiation and tobacco play major roles, although the exact pathogenesis of extrinsic skin aging is not fully understood (Schroder et al., 2006). Discussions about skin aging may change, however, based on work described by Vierkotter et al. in this issue. This article provides evidence that ambient particulate matter (PM) affects skin aging. The authors studied 400 elderly white, northern European women and, using a modified SCINEXA—a validated scoring system for intrinsic and extrinsic aging—found that air pollution exposure contributed to extrinsic aging, in particular, to pigment spot development. Using a cross-sectional design, Vierkotter et al. (2010, this issue) assessed clinical signs of skin aging, including pigment spots, coarse wrinkles, solar elastosis, and telangiectasias, to determine the effects of exposure to PM on extrinsic skin aging. Controlling for potential confounding variables such as age, body mass index, use of hormone replacement therapy, smoking history, Fitzpatrick skin type, history of sunburns, and sun-bed usage, the investigators found that airborne particles contributed to signs of extrinsic aging. In addition, they observed a larger number of lentigines in groups of patients with a higher level of PM exposure. These results suggest other approaches to the prevention of skin aging. Through the following questions, we examine this paper in greater detail. For brief answers, please refer to the supplementary information online
Chemistry and biochemistry of polyvalent iodine compounds. VII. The ARP (apparent reduction potential) of 1,3-dihydro-1-hydroxo-3-oxo-1,2-benziodoxole.

Iodoso compounds are strong oxidizing agents. In order to define an order of magnitude for this oxidizing action, the ARP (apparent reduction potential) of 1,3-dihydro-1-hydroxy-3-oxo-1,2-benziodoxole has been measured using the method of Conant and Lutz. At pH 7.4, the ARP of benziodoxole was 0.327 ± 0.005 v., indicating that this heterocyclic iodine derivative, under the conditions used, is approximately as strong an oxidizing agent as ceric ion. The usefulness of this technique is discussed.
Understanding classroom culture through a theory of dialogism: what happens when cheating and collaboration collide?

We consider tensions between collaboration, ownership, and appropriation in relation to Mikhail Bakhtin's theory of dialogism. We analyze examples of these tensions from our own research in an after-school, design research program and relate them to findings from other research that explored using collaborative learning systems in classrooms. We apply dialogism to describe factors that contribute to students' perception of these classroom experiences as ones that do or do not foster collaboration, including the culture of the classroom, the affordances of the technologies used to mediate collaboration, and the role of multivocality in the classroom. Students are using, reusing, and appropriating media in creative ways outside of their school settings while teachers are increasingly incorporating related emerging technologies such as wikis, blogs, and chat rooms into their classrooms. By understanding the factors that contribute to dialogism, educators will be better equipped to create classroom cultures and design environments to encourage collaboration among students.
The Mini-Mental State Examination in general medical practice: clinical utility and acceptance.

Objective To examine the psychometric properties, acceptance, and screening efficacy of the Mini-Mental State Examination (MMSE) in an internal medicine practice. Material and Methods The MMSE was administered more than 4,000 times by 27 internists to 3,513 elderly patients (2,299 women and 1,214 men, 60 to 102 years old) who underwent general medical examinations. The efficacy of the MMSE for screening was measured in a subsample of age- and sex-matched patients with dementia (N = 185) and control subjects (N = 227). MMSE scores were correlated with age and education in the community sample. The attitudes of physicians about the MMSE were assessed with a 12-question survey. Sensitivity, specificity, and predictive values were calculated. Results Performance on the MMSE among persons older than 59 years was influenced by age and education but not by sex. During an interval of 1 to 4 years, a change of 4 or more points in the total MMSE score is needed to indicate substantial cognitive deterioration. Participating physicians considered the MMSE of little value for routine screening in unselected populations but wanted it available for use as a clinical test. The traditional MMSE cutoff score of 23 or less had a sensitivity of 69% and a specificity of 99%. Use of age- and education-specific cutoff scores improved the sensitivity to 82 % with no loss of specificity. With use of typical base rates for dementia in a general medical practice, the positive predictive value was less than 35%. Conclusion The clinical utility of the MMSE and acceptance by physicians may be improved through awareness of the influences of age and education on the MMSE and by its application in settings with a high base rate of dementia. The MMSE is ineffective when used to screen unselected populations; it should be used for persons at risk of cognitive compromise.
HGF/SF-Met signaling in tumor progression

Tumor progression is a multi-step process that requires a sequential selection of specific malignant phenotypes. Met activation may induce different phenotypes depending on tumor stage: inducing proliferation and angiogenesis in primary tumors, stimulating motility to form micrometastases, and regaining the proliferation phenotype to form overt metastases. To study how HGF/SF-induced proliferative phenotypes switch to the invasive phenotype is important for understanding the mechanism of tumor progression and will provide an attractive target for cancer intervention and therapy.
Mathematical modeling of ammonia electrooxidation kinetics in a Polycrystalline Pt rotating disk electrode

Abstract A mathematical model for the ammonia electrooxidation kinetics, over polycrystalline Pt in alkaline media, was developed through the micro kinetics approach. Two different mechanisms were evaluated for the development of the model, a combined surface-diffusion controlled process and a surface confined process. Nonlinear multiple parameters estimation was implemented by direct comparison with experimental data, obtained in a rotating disk electrode system during linear sweep voltammetry, to calculate the kinetic parameters for the different elementary steps proposed in the mechanisms. It was demonstrated through modeling discrimination techniques that a surface confined process drives the oxidation of ammonia on the implemented electrode surface. The model validates that the formation of N 2 is controlled by the catalytic dimerization of partially reduced ammonia adsorbates (i.e. NH 2(ads) ). Moreover, it confirms that the formation of stronger adsorbed intermediates at high overpotentials is the main cause for the catalyst deactivation.
Adaptive algorithm for distributed signal detection system design

Combining signal detection decisions from multiple sensors is useful in some practical communications, radar, and sonar applications. The optimum schemes for generating and combining the detector decisions have been studied for cases with independent observations from sensor to sensor. Designing schemes for cases with dependent observations from sensor to sensor is a much more difficult problem and to date very little progress has been made. Design approaches which have been suggested for these cases are quite complicated. Here a simple adaptive design approach is outlined for the important and difficult task of detecting a weak random signal in additive, possibly non-Gaussian noise. The approach is based on considering sensor decision rules and fusion rules which contain some unknown parameters. These rules have previously been shown to be optimum for cases with a larger number of observations. These previous results also show that the best parameters minimize the mean square error fit to the best centralized signal detection scheme. Based on these ideas a gradient descent algorithm is proposed for learning the best parameters. Results of the training are compared to known results for multisensor detection schemes.
The effect of the temperature at quenching on the mechanical properties of casting alloys

T he mechanical properties for proprietary alloys of gold under specific conditions of hardening and softening by heat have been comprehensively documented. The advantage of describing alloys in these states is that experimental error in heat treatment can be controlled with an oven thermostat; thus the thermal history of these alloys can be accurately duplicated. The measurement of heat-treated dental alloys in the laboratory is not representative of most clinical experiences because dental castings are usually quenched after casting. Yield strength, tensile strength, and hardness have been well correlated for gold casting alloys.’ The mechanism of hardening has been primarily addressed.2-s The effects of quenching on mechanical properties, however, have not been published. The purpose of this study was to document the mechanical properties of dental castings that have thermal histories similar to those of castings commonly made in dental practice.
A critical analysis of the determination of deformation mechanisms by strain rate change tests

Abstract The strain rate change test used by Yoshinaga et al. to distinguish between the controlling deformation mechanisms in Al and Al-5.4%Mg is critically analyzed. It is demonstrated that the apparent differences in the response of these two materials to strain rate changes are caused not by fundamental differences in flow behavior but by limitations in experimental resolution. In particular, we show that the plastic strain rate does not change discontinuously for Al, as claimed by Yoshinaga et al. and that the high temperature flow of both Al and Al-Mg can be characterized by a finite effective stress. The method of Holbrook et al., in which plastic strain rate continuity is assumed, is used to determine the experimental resolution needed to detect plastic strain rate continuity for the strain rate change test. We show that the differences observed by Yoshinaga et al. can be predicted from their estimated experimental resolution using the constant structure creep properties of Al and Al-Mg.
Multiple access protocols for high-speed networks

Optical fibers have the potential to carry tens and even hundreds of Gbits/sec of information. The question of how to share these large capacities between many users through an efficient, flexible, and low cost network is a challenge. Standards are now being proposed that will decide the protocol for what might be called the third generation of local area and metropolitan area networks. This article explores the principal classes of protocols that permit efficient sharing of high-speed channels.
Low-Temperature STM Images of Methyl-Terminated Si(111) Surfaces

Low-temperature scanning tunneling microscopy (STM) has been used to image CH3-terminated Si(111) surfaces that were prepared through a chlorination/alkylation procedure. The STM data revealed a well-ordered structure commensurate with the atop sites of an unreconstructed 1 × 1 overlayer on the silicon (111) surface. Images collected at 4.7 K revealed bright spots, separated by 0.18 ± 0.01 nm, which are assigned to adjacent H atoms on the same methyl group. The C−H bonds in each methyl group were observed to be rotated by 7 ± 3° away from the center of an adjacent methyl group and toward an underlying Si atom. Hence, the predominant interaction that determines the surface structure arises from repulsions between hydrogen atoms on neighboring methyl groups, and secondary interactions unique to the surface are also evident.
Factors Altering the Filling of the Isolated Left Ventricle of the Dog Heart Effects of Epinephrine and Norepinephrine

Ventricular filling was studied in an isolated left ventricle preparation, and mechanical impedance of the ventricular wall was computed throughout the filling period. Changes in work load or heart rate were accompanied by changes in intraventricular pressure curve contours and in the timecourse of the mechanical impedance throughout filling. The filling pattern is characteristically altered as work load or heart rate increases, and after the administration of epinephrine or norepinephrine.
Intended use of proceeds and the long-run performance of seasoned equity issuers

Abstract We investigate the relation between seasoned equity issuers' stated intended use of proceeds and their subsequent long-run stock and operating performance. Stated intended uses of proceeds are: investment, recapitalization, and general corporate purposes. We find that issuers stating recapitalization or general corporate purposes experience abnormally poor performance in the subsequent three years, but issuers stating investment display little or no subsequent underperformance. These results suggest that issuers with specific plans to use the proceeds for investment purposes are credibly signaling profitable investment opportunities, whereas issuers without specific investment plans are more likely to be opportunistic market timers. Consistent with a timing motive, the secondary component of the offering is significantly larger when the issuer is not specific about investment plans.
Effect of Cytoplasm on the Agronomic Performance of Grain Sorghum Hybrids

Hybrid sorghum [Sorghum bicolor (L.) Moench] seed production relies exclusively on cytoplasmic male sterility (CMS) systems and almost all hybrid sorghum seed is produced using the A1 CMS system. However, the reliance on a single CMS system increases the vulnerability of the crop to diseases and stresses that may attack that particular CMS system. Alternative CMS systems have been described and even used on a limited basis for hybrid seed production, but a direct comparison of the agronomic effects of different cytoplasms has not been possible because male-sterile lines with a common genetic background (and different cytoplasm) were not available. The recent development of isocytoplasmic A-lines allows more direct comparison of cytoplasmic effect on agronomic performance. The purpose of this study was to determine by means of a set of isocytoplasmic hybrids if cytoplasm per se influences agronomic performance. Twelve hybrid genotypes were created in three different cytoplasms (Al, A2, and A3 for a total of 36 hybrids), and they were evaluated for plant height, days to anthesis, and grain yield at Weslaco and College Station, TX, in 1998 and 1999. As expected, significant differences existed among hybrids for plant height, days to anthesis, and grain yield. Cytoplasm type had no effect on plant height and was of minimal practical effect on days to anthesis, but a significant reduction in yield was observed in A3 cytoplasm hybrids as compared with A1 and A2 cytoplasm hybrids. The specific reason for the reduced yield of A3 hybrids is not known, but seed set data indicated that it was not associated with fertility restoration. The results indicate that hybrids created in A2 cytoplasm yield comparably to the commonly used A1 cytoplasm and therefore, the A2 system will provide a suitable alternative for hybrid seed production should problems be encountered in the A1 CMS system.
An analysis of age and body weight at first calving for Holsteins in the United States.

Abstract In a national survey of US dairy producers, only 2.7 ± 0.5% of Holstein dairy operations reported achieving recommended target ranges of age ≤ 24 months and body weight (BW) ≥ 550 kg at first calving. Allowing for wider target ranges, still only 14.6 ± 1.3% of Holstein dairy operations reported achieving age ≤ 25 months and BW ≥ 544.3 kg at first calving. Ages of individual first-calf heifers observed at calving were heavily skewed toward older individuals. Dairy producers reported an average age at first calving that was 1.3 months lower than the mean and 1.0 months lower than median age of first-calf heifers' observed calving on the operations. Stepwise logistic regression was used to identify the herd characteristics associated with producers reporting first calvings within the wider age and BW target ranges for Holsteins. Rolling herd average milk production ≥ 7711 kg/yr, using a computer for recordkeeping, and not tying preweaned heifers in a barn with cows, were associated with achieving the target BW and age at first calving.
Direct versus Indirect Estimation of Feed Efficiency as a Measure of Performance

Abstract THE general problem deals with feed utilization efficiency as a measure of over-all performance and as a criterion for selection in a breeding program. In particular, we wish to consider how important it is to measure feed consumption directly to validly estimate feed efficiency. Even though this paper deals specifically with the efficiency of egg production in laying hens, we believe the concept is applicable to any class of animals which is fed primarily to produce an animal product. A performance index, to be most useful, should reflect production output, market value and costs of production. Typically, the largest production cost is feed. In most random-sample poultry tests, differences in performance between entries are based on records of income over feed and chick costs. The question is if feed measurement sufficiently enhances the estimation of performance efficiency to justify the additional work required. This would be especially important if a…
SPIRAL WAVES AND THE HEART

The human heart normally beats at a fairly regular rate of once per second. Under abnormal conditions, however, the heart may beat irregularly, at fast rates, leading quickly to death. The most dangerous of these irregular heart rhythms are due to recirculating electrical waves of activity. However, the detailed mechanisms of these “reentrant arrhythmias” are unclear. It has been suggested that these recirculating waves are spiral waves. This review article presents recent studies of the heart providing evidence that reentrant arrhythmias result from spiral waves of electrical activity. Spiral waves are generic to many excitable media, therefore the theory of spiral waves is well developed and also reviewed herein. Many of the predictions of spiral wave theory are being realized in the heart and leading investigators in new directions.
Inadequacy of computable loop invariants

Hoare logic is a widely recommended verification tool. There is, however, a problem of finding easily checkable loop invariants; it is known that decidable assertions do not suffice to verify while programs, even when the pre- and postconditions are decidable. We show here a stronger result: decidable invariants do not suffice to verify single-loop programs. We also show that this problem arises even in extremely simple contexts. Let N be the structure consisting of the set of natural numbers together with the functions S(x)=x+1,D(x)=2(x)=***x/2***. There is a single-loop program *** using only three variables x,y,z such that the asserted program x=y=z=0 *** false is partially correct on N but any loop invariant I(x,y,z) for this asserted program is undecidable.
Preliminary Experiments on the use of Chlorpicrin as an Insect Fumigant in Flour and Cereal Mills

Chlorpicrin, the “tear gas” of war days, has been very successfully used to combat common insects found in flour and cereal mills. The liquid chlorpicrin, diluted with an equal quantity by volume of carbon tetrachloride, is best applied within the milling equipment by vaporizing the fumigant in the elevator heads while the mill is running. It is this use of the fumigant within the machines and elevator legs without fire hazard and without serious personal danger that constitutes its greatest advantage. Small amounts of it can be used to destroy infestations in conveyors, bins, or pieces of idle equipment without interfering with the normal operation of the mill. The preliminary experiments indicate plainly that frequent fumigations with chlorpicrin will keep mill infesting insects down to minimum numbers and greatly increase the intervals at which general fumigations are necessary.
Estimating the indirect cost of illness: an assessment of the forgone earnings approach.

OBJECTIVES: This study attempted to assess (1) the accuracy of estimates of the indirect cost of illness and death computed with the human capital (forgone earnings) method and (2) the sensitivity of these estimates to key assumptions and parameters. METHODS: The study used data from the annual Current Population Surveys of 1964 through 1988 to compare the earnings experience of cohorts of White men aged 18 through 65 with predictions made with the human capital method. The study then assessed the sources and magnitude of the observed differences. RESULTS: Predictions of forgone earnings can be as much as 18% greater or 20% smaller than actual earnings, under identical assumptions, depending on the data used. While in most cases errors are quite small, alternative, equally plausible estimates of forgone earnings may differ by as much as 50%. Estimates differed mainly because of (1) the cross section chosen to make the predictions and (2) assumptions about future earnings growth. However, other factors, such as cohort size, also contributed to variation. CONCLUSIONS: Researchers and policymakers should be very careful in making and interpreting estimates of the indirect cost of illness and death.
Classroom applications of marine and environmental remote sensing data

The US Coast Guard Academy teaches remote sensing as a capstone course to their junior and senior marine and environmental sciences majors. Students apply knowledge learned in other courses toward the interpretation and analysis of marine and environmental satellite data. The classroom portion of the course first provides an overview of the theoretical aspects of determining geophysical properties from space, and then looks at how remote sensing can be used to study specific ocean and atmospheric processes including stratospheric ozone, phytoplankton, weather, ocean circulation, El Nino, fisheries, and polar sea ice. A lab curriculum also supports the classroom portion of the course. The Remote Sensing laboratory employs data from the Coastal Zone Color Scanner (CZCS), Advanced Very High Resolution Radiometer (AVHRR), Total Ozone Mapping Spectrometer (TOMS), and Special Sensor Microwave Imager (SSM/I). Future plans call for developing a more general classroom/lab curriculum which other educators can readily incorporate into their own classroom, to be placed on the World Wide Web (WWW) and eventually CD-ROM.
Does Local Labeling Complement or Compete with Other Sustainable Labels? A Conjoint Analysis of Direct and Joint Values for Fresh Produce Claim

As a way to explore the increasing use of sustainability labels in the marketplace, this study analyzes the differential values and interactive effects of sustainable production claims (organic, fair trade, and carbon footprint) and location claims through a conjoint choice experiment included in a 2008 U.S. survey. Locally grown is the highest valued claim, and its value is further enhanced with fair trade certification, but carbon-intensive local products are discounted more severely than those sourced from other locations. Some negatively valued claims (imports and carbon footprint) can be mitigated by combining them with other claims (organic and fair trade). Copyright 2011, Oxford University Press.
Risk-Cost Analysis Under Uncertainty of the Disposal of Contaminated Dredged Material

Risk-cost analysis can be used as a management tool to help determine which water resource management alternatives best satisfy both ecological and economic concerns. However, risk and cost assessments are often associated with very large uncertainties stemming from such factors as contaminant transport modelling and loss function assessment. If risk-cost analysis is conducted without considering these uncertainties, inappropriate management policies may result. On the other hand, considering these uncertainties may cause difficulties in decision making if they make management alternatives effectively indistinguishable. Disposal of contaminated dredged material is a water resource problem where both risks and costs are important considerations. Risks from disposal of contaminated dredged material may be reduced by incorporating measures to confine the contaminated dredged material; however, these confinement measures may increase disposal costs significantly.
The Androgen Receptor Induces Integrin α6β1 to Promote Prostate Tumor Cell Survival via NF-κB and Bcl-xL Independently of PI3K Signaling

Recent studies indicate that androgen receptor (AR) signaling is critical for prostate cancer cell survival, even in castration-resistant disease wherein AR continues to function independently of exogenous androgens. Integrin-mediated adhesion to the extracellular matrix is also important for prostate cell survival. AR-positive prostate cancer cells express primarily integrin α6β1 and adhere to a laminin-rich matrix. In this study, we show that active nuclear-localized AR protects prostate cancer cells from death induced by phosphoinositide 3-kinase (PI3K) inhibition when cells adhere to laminin. Resistance to PI3K inhibition is mediated directly by an AR-dependent increase in integrin α6β1 mRNA transcription and protein expression. Subsequent signaling by integrin α6β1 in AR-expressing cells increased NF-κB activation and Bcl-xL expression. Blocking AR, integrin α6, NF-κB, or Bcl-xL concurrent with inhibition of PI3K was sufficient and necessary to trigger death of laminin-adherent AR-expressing cells. Taken together, these results define a novel integrin-dependent survival pathway in prostate cancer cells that is regulated by AR, independent of and parallel to the PI3K pathway. Our findings suggest that combined targeting of both the AR/α6β1 and PI3K pathways may effectively trigger prostate cancer cell death, enhancing the potential therapeutic value of PI3K inhibitors being evaluated in this setting. Cancer Res; 71(7); 2739–49. ©2011 AACR .
Structure-Less Message Aggregation (SLMA): Reliably and Efficiently Improve Information Precision and Certainty for VANETs

In VANETs, message aggregation is crucial to reduce information redundancy and communication overhead. In addition, it can effectively decrease the information inaccuracy from the on-board sensors. In this paper, we propose a novel scheme, event driven structure-less message aggregation (SLMA), for safety-relevant VANET applications. The key motive of SLMA is to reliably and efficiently improve information accuracy and reduce communication overhead with limited delay at the same time. To our best knowledge, this is the first paper to address these goals of message aggregation simultaneously in VANETs. Using multiple level parallel fusion model to provide high reliability, the structure-less aggregation framework eliminates packet exchanges for aggregation structure formation and maintenance. Bayesian fusion algorithm is adopted to effectively achieve precise event detection on the road. Simulation results show that SLMA scheme efficiently reduces the communication overhead with reasonable delay. Meanwhile, it can greatly improve information accuracy.
Mechanics, modulation and modelling: how muscles actuate and control movement

Animal movement is often complex, unsteady and variable. The critical role of muscles in animal movement has captivated scientists for over 300 years. Despite this, emerging techniques and ideas are still shaping and advancing the field. For example, sonomicrometry and ultrasound techniques have enhanced our ability to quantify muscle length changes under in vivo conditions. Robotics and musculoskeletal models have benefited from improved computational tools and have enhanced our ability to understand muscle function in relation to movement by allowing one to simulate muscle-tendon dynamics under realistic conditions. The past decade, in particular, has seen a rapid advancement in technology and shifts in paradigms related to muscle function. In addition, there has been an increased focus on muscle function in relation to the complex locomotor behaviours, rather than relatively simple (and steady) behaviours. Thus, this Theme Issue will explore integrative aspects of muscle function in relation to diverse locomotor behaviours such as swimming, jumping, hopping, running, flying, moving over obstacles and transitioning between environments. Studies of walking and running have particular relevance to clinical aspects of human movement and sport. This Theme Issue includes contributions from scientists working on diverse taxa, ranging from humans to insects. In addition to contributions addressing locomotion in various taxa, several manuscripts will focus on recent advances in neuromuscular control and modulation during complex behaviours. Finally, some of the contributions address recent advances in biomechanical modelling and powered prostheses. We hope that our comprehensive and integrative Theme Issue will form the foundation for future work in the fields of neuromuscular mechanics and locomotion.
Real-Time Sensor-Actuator Networks

Emerging technologies offer new paradigms for computation, control, collaboration, and communication. To realize the full potential of these technologies in industry, defense, and homeland security applications, it is necessary to exploit the real-time distributed computing capabilities of sensor– actuator networks. To reliably design and develop such networks, it is necessary to develop deeper insight into the underlying model for real-time computation and the infrastructure at the node level that supports this model. In this paper, we discuss a new node-level operating system and mechanisms necessary to deploy reliable applications. The overriding issue that guides the design of this operating system is quality of service metric called predictability. A sensor–actuator network is a distributed platform for integrated computation and control in real-time environments. The nodes in such a network are distinguished by being resource constrained. The power of the network arises from the interactions between simple nodes. Such a network extends the popular distributed sensor networks in several dimensions. After identifying a real-time model, we develop a notion of predictability for a sensor–actuator network. We discuss how the node-level operating system is designed in the resource-constrained environment. An efficient multithreading mechanism and scheduling strategy are required to ensure that local tasks are executed within jitter bounds and that end-to-end delays do not violate application constraints. Mechanisms to support communication, monitoring, safety, fault tolerance, programming, diagnosability, reconfiguration, composability, interoperability, and security are discussed.
Analysis of elastic symmetry from velocity measurements with application to dunite and bronzitite

SUMMARY A practical quantitative method is presented for determining an appropriate symmetry and coordinate system in which to express the elastic tensor of rocks. While previous methods have been presented for finding appropriate coordinate system from arbitrary elastic tensors, these methods are either qualitative or purely mathematical and have no mechanism for minimizing the effect of errors which occur when elastic tensors are obtained from real data. In order to find an appropriate coordinate system, a complete elastic tensor must be contracted to one of two symmetric second rank tensors. The principal axes of this tensor are the axes of the coordinate system in which the complete elastic tensor is to be expressed. The traces of the various contracted tensors are scalar invariants which are related to Voight and Reuss moduli. One of these traces also yields a new scalar property, a velocity invariant for anisotropic media. This invariant is the sum of the squares of the three phase velocities in three mutually orthogonal directions and is a quantity whose nature is similar to density. Once an appropriate coordinate system has been found, the highest symmetry that will adequately fit the velocity data can be determined statistically. This method is demonstrated with velocity measurements in dunite and bronzitite made by Babuska (1972). Velocity maxima obtained in this paper differ by 13"-21" from those obtained petrographically by Babuska (1972). Further, the symmetry of dunite sample and bronzitite sample can be
How do UV photomorphogenic responses confer water stress tolerance

Although ultraviolet-B (UV-B) radiation is potentially harmful, it is an important component of terrestrial radiation to which plants have been exposed since invading land. Since then, plants have evolved mechanisms to avoid and repair UV radiation damage; therefore, it is not surprising that photomorphogenic responses to UV-B are often assumed to be adaptations to harmful radiation. This presupposes that the function of the observed responses is to prevent UV damage. It has been hypothesized that, as with blue light, UV-B provides a signal important for normal plant development and might be perceived within developing plants through nondestructive processes, perhaps through UV-specific signal perception mechanisms. UV signal perception can lead to photomorphogenic responses that may confer adaptive advantages under conditions associated with high-light environments, such as water stress. Plant responses to UV radiation in this regard include changes in leaf area, leaf thickness, stomatal density, photosynthetic pigment production and altered stem elongation and branching patterns. Such responses may lead to altered transpiration rates and water-use efficiencies. For example, we found that the cumulative effect of ambient UV-B radiation upon stomatal density and conductance can lead to altered water-use efficiencies. In field settings, UV might more properly be viewed as a photomorphogenic signal than as a stressor. Hence, it might be insufficient to attempt to fully evaluate the adaptive roles of plant responses to UV-B cues upon stress tolerance by the simultaneous application of UV and drought stress during development. We propose that rather than examining a plant's response to combinations of stressors one might also examine how a plant's response to UV induces tolerance to subsequently applied stresses.
High energy proton emission in reactions induced by 315 MeV 16O ions

Abstract Inclusive proton spectra have been measured for the reaction 197Au(16O, p)X at 315 MeV. The data, which are consistent with emission from a moving source, are compared with the fireball model and with models preequilibrium emission.
Microfluidic purification and analysis of hematopoietic stem cells from bone marrow

Hematopoietic stem cells are larger in size than other cells present in bone marrow, with the exception of monocytes. This distinguishing characteristic can be used to separate them from a whole-marrow sample. A microfluidic device was fabricated using an integrated membrane that is porous at defined areas. This allows for simultaneous valving and filtering functionality, which is crucial for preventing irreversible clogging. This device, as well as a separation procedure, was optimized in this work to enrich hematopoietic progenitor cells from diluted bone marrow of leukemia patients without any additional sample preparation. An enrichment of up to 98% was achieved with this method and the process was scaled up to 17.2 μL min−1 of processed sample. Additionally, stem cells were stained with specific antibodies for further analysis. Using a custom-made computer program, the filter was scanned to characterize and quantify cells based on fluorescence. The results were evaluated by comparing them against the results obtained from flow cytometry, confocal microscopy, and Coulter counting.