cssi/SciSciGPT-SciSciNet huggingface dataset:
The aerodynamics of axisymmetric blunt bodies flying at angle of attack

The Mars Science Laboratory entry capsule is used as an example to demonstrate how a blunt body of revolution must be treated as asymmetric in some respects when flying at a non-zero trim angle of attack. A brief description of the axisymmetric moment equations are provided before solving a system of equations describing the lateral-directional moment equations for a blunt body trimming at an angle of attack. Simplifying assumptions are made which allow the solution to the equations to be rearranged to relate the roll and yaw stability with sideslip angle to the frequency of oscillation of the vehicle body rates. The equations show that for a blunt body the roll and yaw rates are in phase and proportional to each other. The ratio of the rates is determined by the static stability coefficients and mass properties about those axes. A trajectory simulation is used to validate the static yaw stability parameter identification equation and a simple method of identifying the oscillation frequency from the body rates. The approach is shown to successfully extract the modeled yaw stability coefficient along a simulated Mars entry. Mars Science Laboratory flight data results are presented from earlier work which indicate that results from both the validation case and flight data are in agreement with preflight predictions. A brief discussion of the dynamic stability is also provided. Trimming at a nonzero angle suggests that the typical axisymmetric models of the dynamic stability coefficients should be modified. However, further experimental or computational work must be done to separate damping due to body rates and wind relative rates before the correct lifting formulation would affect simulation results.
Likelihood ratios for continuous test results : making the clinicians' job easier or harder ?

Clinicians' paradigms for considering diagnostic test results require decisions based on the actual test value. However, when the test result is reported on a continuous scale each possible outcome may not result in unique actions. To simplify decision making, clinicians often break down the continuous scale into dichotomous or ordered outcomes. Likelihood ratios, reported with the test outcome, help summarize the impact of diagnostic tests. Although commonly applied to dichotomous outcomes, likelihood ratios can also be applied to ordinal or continuous results. This application allows investigators to consider the effect of clinically simplifying continuous data into dichotomous or ordinal categories. The parameters of a simple logistic regression equation summarize continuous likelihood ratios, evaluate covariates, generate likelihood ratio lines, and help assess the statistical significance of more complex models. Having visually inspected likelihood ratio lines and considered statistical differences, the investigator should choose the test report format that best accounts the realities driving clinical decisions.
Performance assessment of major wastewater treatment plants (WWTPs) in the state of Georgia.

A survey was conducted to report on the types and efficiencies of various treatment technologies being used at major wastewater treatment plants (WWTPs) in the state of Georgia. Twenty-four, full-scale wastewater treatment facilities with a design capacity of 37,850 m3 d−1 (10 Mg d−1) or greater were evaluated. One year of operating data for the 2003 calendar year was obtained from discharge monitoring reports (DMRs) provided by the Georgia Environmental Protection Division (EPD) in Atlanta. Additional information was gathered about facility operations and the types of chemicals used through review of EPD files and interviews with plant personnel. Data evaluated were: influent and effluent five-day Biochemical Oxygen Demand (BOD5), influent and effluent total suspended solids (TSS), effluent ammonia nitrogen (NH3-N), and effluent Total Phosphorus (TP). Effluent requirements for BOD5 or five-day carbonaceous biochemical oxygen demand (CBOD5), TSS, ammonia nitrogen (NH3-N), TP, and dissolved oxygen (DO) var...
Even simple neural nets cannot be trained reliably with a polynomial number of examples

A variation of L.G. Valiant's 'PAC' model of learnability (Commun. ACM, vol.27, no.11, p.1134-42, 1984; Proc. 9th Int. Joint Conf. Artif. Intell., Aug. 1985) is used to investigate the learning power of artificial neural nets with threshold nodes. It is shown that there are cases where simple nets require an exponential number of training examples for reliably determining their sets of parameters. Polynomially many training examples may not be enough to determine the set of parameters even for a net of three threshold nodes, if it has to perform reliably in two different environments. >
The effectiveness of large household water storage tanks for protecting the quality of drinking water.

Many communities along the US-Mexico border remain without infrastructure for water and sewage. Residents in these communities often collect and store their water in open 55-gallon drums. This study evaluated changes in drinking water quality resulting from an intervention that provided large closed water storage tanks (2,500-gallons) to individual homes lacking a piped water supply. After the intervention, many of the households did not change the source of their drinking water to the large storage tanks. Therefore, water quality results were first compared based on the source of the household's drinking water: store or vending machine, large tank, or collected from a public supply and transported by the household. Of the households that used the large storage tank as their drinking water supply, drinking water quality was generally of poorer quality. Fifty-four percent of samples collected prior to intervention had detectable levels of total coliforms, while 82% of samples were positive nine months after the intervention (p 10 CFU/100 ml). Mean free chlorine levels dropped from 0.43 mg/l, where the trucks filled their tanks, to 0.20 mg/l inside the household's tank immediately after delivery. Results of this study have implications for interventions that focus on safe water treatment and storage in the home, and for guidelines regarding the level of free chlorine required in water delivered by water delivery trucks.
Structure and Bonding in β-HMX-Characterization of a Trans-Annular N···N Interaction

Chemical bonding in the β-phase of the 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX) crystal based on the experimental electron density obtained from X-ray diffraction data at 20 K, and solid state theoretical calculations, has been analyzed in terms of the quantum theory of atoms in molecules. Features of the intra- and intermolecular bond critical points and the oxygen atom lone-pair locations are discussed. An unusual N···N bonding interaction across the 8-membered ring has been discovered and characterized. Hydrogen bonding, O···O and O···C intermolecular interactions are reported. Atomic charges and features of the electrostatic potential are discussed.
Management of cerebrospinal fluid leakage from cochleostomy during cochlear implant surgery

Objectives: The objectives of this retrospective review were to determine the incidence of cerebrospinal fluid (CSF) otorrhea from the cochleostomy during cochlear implant surgery, to recognize patients at risk, and to determine the appropriate preoperative, postoperative and intraoperative management. Methods: A chart review from two cochlear implant centers was performed to determine the incidence of CSF otorrhea, patients at risk, and appropriate management. Results: The incidence of CSF gusher is low, encountered in approximately 1% of patients undergoing cochlear implant surgery, and is seen in equal incidence in children and adults in our series. Preoperative imaging was predictive in only 50% of cases. Mechanisms for otorrhea in specific cochlear malformations and in those in which no apparent malformation exists are discussed. Successful implantation is expected in most cases. Intraoperative management may require complete packing of the middle ear space in addition to the cochleostomy to control CSF leak. Lumbar drain is rarely necessary. Outpatient management is possible in the majority of cases. Vaccination and antibiotic prophylaxis is essential. Conclusions: CSF otorrhea can be encountered in cochlear malformations and in cochleas without apparent malformation. Successful implantation without short-term or long-term complications is expected.
Parametrization over inductive relations of a bounded number of variables

Abstract We present a Parametrization Theorem for (positive elementary) inductions that use a bounded number of variables. We investigate associated halting problem(s) on classes of finite structures and on solitary ‘unreasonable’ structures. These results involve the complexity of the inductive relations—and the complexity of the structure or class of structures on which these relations live. We also apply this Parametrization Theorem to Moschovakis closure ordinals, to determine when the closure ordinal is greater than ω, and to investigate the closure ordinals of unreasonable structures.
On the rigidity of Vandermonde matrices

Abstract The rigidity function R A (r) of a matrix A is the minimum number of entries of A that must be changed to reduce the rank of A to less than or equal to r . While almost all matrices have rigidity close to (n−r) 2 , proving strong lower bounds on the rigidity of explicit matrices is a fundamental open question with several consequences in complexity theory. A natural class of matrices expected to have high rigidity is that of Vandermonde matrices V=(x i j−1 ) 1⩽i, j⩽n . However, even when the x i are algebraically independent, it was not known if R V (r)= Ω (n 2 ) for nonconstant r . We prove that for any constant c , there exists a constant e>0 such that if r⩽e n , then R V (r)⩾cn 2 , when the x i are algebraically independent. Although not explicit, this provides a natural n -dimensional manifold in the space of n×n matrices with Ω (n 2 ) rigidity for nonconstant r . Our proof is based on a technique due to Shoup and Smolensky (Comput. Complexity 6(4) (1997) 301–311). For explicit Vandermonde matrices, the best-known lower bound is R V (r)= Ω (n 2 /r log (n/r)) , when log 2 n⩽r⩽n/2 , which follows from a result of Shokrollahi et al. (Inform. Process. Lett. 64(6) (1997) 283–285).
When starting over makes more sense

Proofreading mechanisms intrinsic to DNA and RNA polymers that contribute substantially to overall fidelity are lacking in the ribosome. New evidence, however, suggests that quality control in translation can occur after substrate incorporation by an abortive mechanism entailing premature release factor-catalyzed termination. These data shed new light on the importance and ubiquity of retrospective quality control mechanisms in ensuring the overall fidelity of nature's processive enzymes and demonstrate that competitive elongation reactions on the ribosome are kinetically sensitive to compositional features of the translating particle.
The History of Inertial Navigation

Practical inertial navigation is a quite recent achievement, only twenty-five years for serious research and development and only five for its commercial use. However, one might possibly say that a partial understanding of some of its principles is much more ancient. For example, in the Bible1 we read that God used a plumb-line to identify a particular location!
Piperidine Acetic Acid Based γ-Secretase Modulators Directly Bind to Presenilin-1

Aβ42 is believed to play a causative role in Alzheimer’s disease (AD) pathogenesis. γ-Secretase modulators (GSMs) are actively being pursued as potential AD therapeutics because they selectively alter the cleavage site of the amyloid precursor protein (APP) to reduce the formation of Aβ42. However, the binding partner of acid based GSMs was unresolved until now. We have developed clickable photoaffinity probes based on piperidine acetic acid GSM-1 and identified PS1 as the target within the γ-secretase complex. Furthermore, we provide evidence that allosteric interaction of GSMs with PS1 results in a conformational change in the active site of the γ-secretase complex leading to the observed modulation of γ-secretase activity.
On the Physical Characteristics of the Hydra Cluster of Nebulae.

A. Observational Data. - In a previous paper [1] counts of the brighter nebulae in the Hydra cluster were communicated. The distance of the Hydra cluster was estimated as 7.3 X 10^6 parsecs and the average apparent velocity of recession to be expected was given as v = 4100 km./sec. No observations of the red shift for nebulae in the Hydra cluster were available at the time. Dr. Hubble subsequently obtained a spectrum plate for NGC 3309 which nebula is a member of the Hydra cluster. He kindly informs me that the apparent velocity of recession for NGC 3309 is of the order of 3950 km./sec., a value which is in good agreement with our original estimate. B. The Radial Distribution of Nebulae in the Hydra Cluster. - As emphasized previously [1] the Hydra cluster exhibits spherical symmetry and is therefore suspected to have reached a statistically stationary state. In order to check this conclusion two additional tests are available. In the first place we may compare the observed radial distribution of nebulae in the Hydra cluster with the distribution derived by Emden [2] for the bounded isothermal gravitational gas sphere and secondly we can verify whether the ratio wr^2/p0 of the square of the dispersion in radial velocities of the cluster nebulae to the central density po of the cluster can be correctly determined from the observed structural length or structural index a of the cluster [3].
A relation between the driving force and geoid anomaly associated with mid-ocean ridges

The driving force and geoid anomaly associated with the thermal structure of the oceanic plates are shown to be proportional to the first moment of the density structure with respect to depth and, hence, to each other. Both quantities exhibit the same functional dependence on age and this is given for two different thermal models. For the plate model the geoid anomaly and ridge driving force only increase slowly for ages greater than 40 m.y. in contrast to the half-space boundary layer model where a linear dependence on age holds for all ages. Isolation of the geoid anomaly related to the thermal structure of the plates would provide a direct measure of the magnitude of the ridge driving force.
Concreteness of Idiographic Periods of Worry and Depressive Rumination

Stober (Behav Res Ther 36:751–756, 1998) asserts that worry is characterized by reduced concreteness of thought that interferes with successful emotional processing via reduction of imagery. Extant research has not examined concreteness of thought during a period of idiographic worry, nor has it directly compared concreteness during worrisome thinking to concreteness during other types of repetitive negative thinking such as depressive rumination. We sought to test Stober’s theory as it relates to idiographic periods of worry, and further examined its applicability to periods of depressive rumination. Consistent with Stober’s theory, we found that worry and depressive rumination were significantly and non-differentially more abstract than was baseline mentation. Contrary to Stober’s theory, concreteness of thought was not related to degree of reported imagery during either worry or depressive rumination. Theoretical and clinical implications of these findings are discussed.
Thermal-Mechanical Analysis of a Low-Enriched Uranium Foil Based Annular Target for the Production of Molybdenum-99

One of the US Department of Energy’s Global Threat Reduction Initiative (GTRI) goals is the elimination of the use of high enriched uranium (HEU) for the production of the radioisotope molybdenum-99 (Mo-99). One strategy to achieve this goal is to use an irradiation target that utilizes a low-enriched uranium (LEU) foil. This paper considers an annular target geometry, where an LEU foil of open cross section is sandwiched between two concentric aluminum tubes. A recess is cut on the inner tube to hold the LEU foil and facilitate assembly. The target must contain the fission products until it can be opened and the LEU foil removed for further processing. The thermal contact resistance between the LEU foil and the aluminum tube cladding needs to be low enough to ensure that the LEU temperature does not exceed the operating temperature specified by the reactor safety case.Numerical models using the commercial finite element code Abaqus FEA are used to explore the potential for gaps opening between the LEU-foil and the aluminum tubes, and the stresses developed in the aluminum tubes during heat generation in the target during irradiation. Parametric studies are conducted using constructed analytic models to explore the impact of the ratio of heat transfer coefficients between the inner and the outer tubes and the inner-to-outer tube thickness ratio. It is concluded that the current annular target design is safe at high LEU heat generation rates and the use of these targets will likely not compromise the reactor safety.Copyright © 2012 by ASME
The mismetallation of enzymes during oxidative stress

Mononuclear iron enzymes can tightly bind non-activating metals. How do cells avoid mismetallation? The model bacterium Escherichia coli may control its metal pools so that thermodynamics favor the correct metallation of each enzyme. This system is disrupted, however, by superoxide and hydrogen peroxide. These species oxidize ferrous iron and thereby displace it from many iron-dependent mononuclear enzymes. Ultimately, zinc binds in its place, confers little activity, and imposes metabolic bottlenecks. Data suggest that E. coli compensates by using thiols to extract the zinc and by importing manganese to replace the catalytic iron atom. Manganese resists oxidants and provides substantial activity.
Chemical sensing with ZnO nanowire FETs

Zinc oxide nanowires are configured as n-channel field effect transistors. These transistors are implemented as highly sensitive chemical sensors for detection of various gases such as O 2 , NO 2 , NH 3 , and CO at room temperature. They show oxidizing sensing property to oxygen and nitrogen dioxide. Nanowires' ammonia sensing behavior is observed to switch from oxidizing to reducing when temperature increased from 300 to 500 K. This effect is attributed to the temperature dependent chemical potential shift. Carbon monoxide is found to increase the nanowire conductance in the presence of oxygen. Due to a Debye screening length comparable to the nanowire diameter, the electric field applied over the back gate significantly affects the sensitivity as it modulates the carrier concentration. A strong negative field is utilized to refresh the sensors by an electro-desorption mechanism. In addition, different chemisorbed species could be distinguished from the refresh threshold voltage and the temporal response of the conductance. These results demonstrate a refreshable field effect sensor with a potential gas identification function.
Incorporation of redox-active cations into tungsten oxide coatings on electrodes: Enhancement of coating stability and electrocatalytic activity

Abstract The electrochemical deposition of tungsten oxide onto the surface of glassy carbon electrodes produces a coating which exhibits significant cation exchange behavior. Catalysts such as the protonated form of cobalt meso -tetrakis(4-pyridyl)porphyrin (CoTPyP) or cis -[Ru(6,6′−Cl 2 bpy) 2 (OH 2 ) 2 ] 2+ are efficiently bound to the oxide coatings where they serve to catalyze the reduction of O 2 or various oxidation reactions respectively. The combination of the reduced tungsten oxide (hydrogen tungsten bronze) with CoTPyP leads to the reduction of O 2 to H 2 O 2 and subsequently to H 2 O under conditions where CoTPyP alone produces only a two-electron reduction of O 2 .
Receipt of preventive health care services by lesbians.

Abstract Background: We measured receipt of age-appropriate preventive health services by lesbians and assessed whether provider and individual characteristics, including disclosure of sexual orientation, are independently associated with receipt of these services. Methods: A questionnaire was printed in a national biweekly gay, lesbian, and bisexual news magazine, and self-identified lesbians living in all U.S. states ( N =6935) responded to the survey. Main outcome variables were receipt of a Pap smear within the preceding 1 and 2 years and, for women aged ≥50, receipt of a mammogram within the past 1 and 2 years. Results: Fifty-four percent had Pap smears within 1 year and 71% within 2 years, with increasing rates among older and more educated respondents. Seventy percent of respondents aged ≥50 had a mammogram in the past year, and 83% within 2 years; rates did not vary significantly controlling for education. Sixty percent had disclosed their sexual orientation to their regular health care provider. Controlling for patient and provider characteristics, disclosure was independently associated with receipt of Pap smears, but not mammograms. Conclusions: It is important for providers to identify their lesbian patients' unmet needs for preventive health care. Additionally, it is important for providers to provide complete and appropriate preventive health care for their lesbian patients. Further research is needed to determine why lesbians are not receiving Pap smears at the recommended rate and whether this disparity is reflective of aspects of cervical cancer screening or indicates a more general problem with access to health care including receipt of preventive services.
Cerebral Autoregulation Is Minimally Influenced by the Superior Cervical Ganglion in Two- Week-Old Lambs, and Absent in Preterm Lambs Immediately Following Delivery

Cerebral vessels in the premature newborn brain are well supplied with adrenergic nerves, stemming from the superior cervical ganglia (SCG), but their role in regulation of blood flow remains uncertain. To test this function twelve premature or two-week-old lambs were instrumented with laser Doppler flow probes in the parietal cortices to measure changes in blood flow during changes in systemic blood pressure and electrical stimulation of the SCG. In lambs delivered prematurely at ∼129 days gestation cerebral perfusion and driving pressure demonstrated a direct linear relationship throughout the physiologic range, indicating lack of autoregulation. In contrast, in lambs two-weeks of age, surgical removal of one SCG resulted in ipsilateral loss of autoregulation during pronounced hypertension. Electrical stimulation of one SCG elicited unilateral increases in cerebral resistance to blood flow in both pre-term and two-week-old lambs, indicating functioning neural pathways in the instrumented, anesthetized lambs. We conclude cerebral autoregulation is non-functional in preterm lambs following cesarean delivery. Adrenergic control of cerebral vascular resistance becomes effective in newborn lambs within two-weeks after birth but SCG-dependent autoregulation is essential only during pronounced hypertension, well above the normal range of blood pressure.
Smart building real time pricing for offering load-side Regulation Service reserves

Provision of Regulation Service (RS) reserves to Power Markets by smart building demand response has attracted attention in recent literature. This paper develops tractable dynamic optimal pricing algorithms for distributed RS reserve provision. It shows monotonicity and convexity properties of the optimal pricing policies and the associated differential cost function. Then, it uses them to propose and implement a modified Least Squares Temporal Differences (LSTD) Actor-Critic algorithm with a bounded and continuous action space. This algorithm solves for the best policy within a pre-specified broad family. In addition, the paper develops a novel Approximate Policy Iteration (API) algorithm and uses it successfully to optimize the parameters of an analytic policy function. Numerical results are obtained to demonstrate and compare the Actor-Critic and Approximate Policy Iteration algorithms, demonstrating that the novel API algorithm outperforms the Bounded LSTD Actor-Critic algorithm in both computational effort and policy minimum cost.
Aquatic burst locomotion by hydroplaning and paddling in common eiders (Somateria mollissima).

ABSTRACT Common eiders ( Somateria mollissima ) are heavy sea-ducks that spend a large portion of their time swimming at the water surface. Surface swimming generates a bow and hull wave that can constructively interfere and produce wave drag. The speed at which the wavelengths of these waves equal the waterline length of the swimming animal is the hull speed. To increase surface swimming speed beyond the hull speed, an animal must overtake the bow wave. This study found two distinct behaviors that eider ducks used to exceed the hull speed: (1) ‘steaming’, which involved rapid oaring with the wings to propel the duck along the surface of the water, and (2) ‘paddle-assisted flying’, during which the ducks lifted their bodies out of the water and used their feet to paddle against the surface while flapping their wings in the air. An average hull speed (0.732±0.046 m s −1 ) was calculated for S. mollissima by measuring maximum waterline length from museum specimens. On average, steaming ducks swam 5.5 times faster and paddle-assisted flying ducks moved 6.8 times faster than the hull speed. During steaming, ducks exceeded the hull speed by increasing their body angle and generating dynamic lift to overcome wave drag and hydroplane along the water surface. During paddle-assisted flying, ducks kept their bodies out of the water, thereby avoiding the limitations of wave drag altogether. Both behaviors provided alternatives to flight for these ducks by allowing them to exceed the hull speed while staying at or near the water surface.
Performance of Laying Turkeys Grouped According to Daily Food Intake

Abstract The individual food intake of 120 Large White turkey hens in cages was measured for 3 weeks from 36 to 39 weeks of age. Based on that rate of intake, hens were divided into four treatment groups: two high intake (HI) and two low intake (LI). A control diet was fed to one HI group and one LI group. In addition, diets with different nutrient density were formulated for one HI group and one LI group. The experimental period was for 10 weeks beginning when the hens were 39 weeks of age. There were no significant differences among the groups for rate of egg production, total number of eggs, egg weight, or egg specific gravity, although there were significant differences for the daily intakes of protein, sulfur amino acids, lysine, phosphorus, calcium, and metabolizable energy. These data indicate that, at 39 weeks of age, there was no benefit from grouping birds based on previous food intake and feeding them diets to increase or decrease daily intake of certain nutrients.
Cumulative number of altered biomarkers in mammalian target of rapamycin pathway is an independent predictor of outcome in patients with clear cell renal cell carcinoma.

Objective To evaluate the association of the altered expression of the mammalian target of rapamycin (mTOR) pathway components with oncologic outcomes in patients with nonmetastatic clear cell renal cell carcinoma (ccRCC). Materials and Methods Immunohistochemistry for phosphorylated-S6, phosphorylated-mTOR, mTOR, phosphorylated-AKT, hypoxia inducible factor-1α, Raptor, phosphatase and tensin homolog (PTEN), phosphoinositide 3-kinase (PI3K), and phosphorylated 4E-binding protein-1 was performed on tissue microarray constructs of patients treated for nonmetastatic kidney cancer from 1997 to 2010. The relationship between individual altered marker expression and a prognostic marker score (low, intermediate, and high, defined as ≤3, 4-5, >5 altered biomarkers, respectively) and oncologic outcome was assessed. Results The study included 419 patients with nonmetastatic ccRCC, with a median follow-up period of 26 months (range 6-150). The tumors were nonorgan confined (pT3-T4) in 86 (20.5%) and high Fuhrman nuclear grade (3-4) in 131 (31%). A low, intermediate, and high prognostic marker score was found in 214 (51%), 152 (36%), and 53 (13%) patients, respectively. Kaplan-Meier analysis demonstrated a statistically significant correlation between the risk groups and disease recurrence and cancer-specific survival. In a multivariate Cox regression analysis controlling for tumor stage and grade, a high marker score was an independent predictor of disease recurrence (hazard ratio 3.3, 95% confidence interval 1.33-8.39, P = .01), and a combination of a high and an intermediate score was an independent predictor of survival (hazard ratio 4.8, 95% confidence interval 1.27-4.78, P = .008). Conclusion The cumulative number of aberrantly expressed biomarkers correlated with aggressive tumor biology and inferior oncologic outcomes in patients with ccRCC. Our data support prospective pathway-based exploration of the mTOR signaling cascade to augment current clinicopathologic predictors of oncologic outcomes in patients with ccRCC.
Control of dissipative partial differential equation systems using APOD based dynamic observer designs

This article focuses on output feedback control of distributed parameter systems with limited number of sensors employing adaptive proper orthogonal decomposition (APOD) methodology. The controller design issue is addressed by combining a robust state controller with a dynamic observer of the system states to reduce sensor requirements. The use of APOD methodology allows the development of locally accurate low-dimensional reduced order dynamic models (ROMs) for controller synthesis thus resulting in a computationally-efficient alternative to using large-dimensional models with global validity. The derived ROMs are subsequently employed for the design of dynamic observers and controllers. The proposed methods are successfully used to achieve the desired control objective of stabilizing the Kuramoto-Sivashinksy equation (KSE) at a desired state spatial profile.
Type III Interferon Attenuates a Vesicular Stomatitis Virus-Based Vaccine Vector

Vesicular stomatitis virus (VSV) has been extensively studied as a vaccine vector and oncolytic agent. Nevertheless, safety concerns have limited its widespread use in humans. The type III lambda interferon (IFN-λ) family of cytokines shares common signaling pathways with the IFN-α/β family and thus evokes similar antiviral activities. However, IFN-λ signals through a distinct receptor complex that is expressed in a cell type-specific manner, which restricts its activity to epithelial barriers, particularly those corresponding to the respiratory and gastrointestinal tracts. In this study, we determined how IFN-λ expression from recombinant VSV would influence vector replication, spread, and immunogenicity. We demonstrate that IFN-λ expression severely attenuates VSV in cell culture. In vivo, IFN-λ limits VSV replication in the mouse lung after intranasal administration and reduces virus spread to other organs. Despite this attenuation, however, the vector retains its capacity to induce protective CD8 T cell and antibody responses after a single immunization. These findings demonstrate a novel method of viral vector attenuation that could be used in both vaccine and oncolytic virus applications. IMPORTANCE Viruses such as VSV that are used as vaccine vectors can induce protective T cell and antibody responses after a single dose. Additionally, IFN-λ is a potent antiviral agent that has certain advantages for clinical use compared to IFN-α/β, such as fewer patient side effects. Here, we demonstrate that IFN-λ attenuates VSV replication and spread following intranasal virus delivery but does not reduce the ability of VSV to induce potent protective immune responses. These findings demonstrate that the type III IFN family may have widespread applicability for improving the safety and efficacy of viral vaccine and oncolytic vectors.
Calculation of protein-bound iodine from kinetic data.

MOST current methods for the determination of the plasma proteinbound iodine estimate the iodine in the final step by measuring its catalytic, effect on the rate of the reaction between eerie ion and arsenious acid. The rate of the reaction is measured photometrically by following the rate of conversion of the yellow ceric ion to the colorless cerous ion. By interspersing suitable standards between the unknown solutions one can usually interpolate the concentration of the unknown from a standardcurve. Barker et al. (1, 2) have proposed that individual samples might contain other substances which could exert inhibitory or catalytic effects; to obviate this possibility they used two aliquots of the final solution. A known amount of iodide was added to the second aliquot on the assumption that extraneous inhibitors or catalysts would exert a similar effect on both the standard and the unknown; thus, each unknown was compared against a second sample containing the unknown plus a standard amount of iodide. The...
Maximizing Accuracy of Shared Databases when Concealing Sensitive Patterns

The sharing of databases either within or across organizations raises the possibility of unintentionally revealing sensitive relationships contained in them. Recent advances in data-mining technology have increased the chances of such disclosure. Consequently, firms that share their databases might choose to hide these sensitive relationships prior to sharing. Ideally, the approach used to hide relationships should be impervious to as many data-mining techniques as possible, while minimizing the resulting distortion to the database. This paper focuses on frequent item sets, the identification of which forms a critical initial step in a variety of data-mining tasks. It presents an optimal approach for hiding sensitive item sets, while keeping the number of modified transactions to a minimum. The approach is particularly attractive as it easily handles databases with millions of transactions. Results from extensive tests conducted on publicly available real data and data generated using IBM's synthetic data generator indicate that the approach presented is very effective, optimally solving problems involving millions of transactions in a few seconds.
THE GROWTH INHIBITORY EFFECT OF p21 ADENOVIRUS ON HUMAN BLADDER CANCER CELLS

Purpose:: To evaluate whether p21 (WAF-1/CIP1) should be considered a potential candidate for human bladder cancer gene therapy, we determined: (1) the basal level of p21 expression in bladder cancer cell lines, (2) the response of bladder cancer cells to increased p21 expression following p21 adenovirus infection, and (3) the mechanism of growth inhibition produced by p21 overexpression.Materials and Methods:: Five established human bladder cancer cell lines and one primary culture derived from an invasive transitional cell carcinoma were used in this study. To examine the effect of p21 protein on the growth of human bladder cancer cells, a recombinant adenovirus vector system containing p21 cDNA, under the control of cytomegalovirus promoter, was constructed. A control virus containing p21 in an antisense orientation was used to eliminate potential artifacts caused by viral toxicity.Results:: Human bladder cancer cell lines exhibit variable endogenous p21 levels which correlate with the in vitro growth ...
Utility and barriers to performance of the ankle-brachial index in primary care practice

Peripheral arterial disease is prevalent, associated with increased cardiovascular morbidity and mortality, and is underdiagnosed. Nevertheless, systematic efforts to provide early office-based peripheral arterial disease detection are not routinely implemented in office practice. The PARTNERS Program implemented the ankle-brachial index (ABI) measurement in primary care outpatient clinics in order to model practical dissemination of this technique and thus improve office-based peripheral arterial disease detection. The objective of this study was to identify clinician-defined factors that were perceived to foster acceptance of, or create barriers to, the use of the ABI in office practice. The ABI Utilization Survey was administered to primary care clinicians who participated in the PARTNERS Program, as well as to additional primary care clinicians who participated in the PARTNERS Preceptorship. The survey assessed six parameters: pre- and post-participation office ABI utilization; perceived clinical utility of the ABI; perceived value of the ABI data relative to other commonly used office disease detection methods; feasibility of implementing office-based ABI testing; definition of factors limiting utilization of the ABI in office practice; and the role of office staff in performing the ABI test. Survey data were obtained from 886 respondents. A total of 68% of respondents did not measure the ABI prior to participation in the PARTNERS Program. After Program participation, the frequency of office ABI use increased from 12% to 43% weekly and 13% to 39% monthly. The few participants who reported using the ABI only once a year (annually) did not significantly change after the program. Most clinicians believed that the ABI was useful in the diagnosis and management of both symptomatic (96%) and asymptomatic (89%) peripheral arterial disease. Moderate to major barriers to use of the ABI included time constraints (56%), lack of reimbursement (45%), and staff availability (45%). Nearly all (88%) clinicians believed that it was feasible to incorporate ABI into daily practice. Overall, most clinicians (57-75%) believed that ABI was equal to, or more useful, than other widely available and reimbursed screening tests in preserving their patients' health. In conclusion, the ABI was perceived by primary care clinicians to be a clinically useful diagnostic test. Limited reimbursement and time were identified as the primary barriers to its widespread use. Once learned, most clinicians stated that the ABI would continue to be frequently used in their office practice. The ABI is a simple peripheral arterial disease detection tool that can be successfully applied in primary care office practices.
Controlling Uncertain Systems within a Subset of the State Space

In previous work, stabilizing controllers were developed for uncertain systems whose state space is Rn. Here, we present stabilizing controllers for uncertain systems whose state space is some open subset of Rn or for which it is desired to keep all state motions within some open subset of Rn. The controllers, whose construction is based on Lyapunov theory, are, in general, nonlinear. Their use is illustrated by an example.
Admission control and resource allocation in a heterogeneous OFDMA wireless network

We study the problem of admission control and resource (subcarriers, power and bit-loading) allocation in a heterogeneous OFDMA wireless network serving both QoS-constrained high-priority users and best-effort users. By clustering subcarriers, efficient algorithms for cluster and power allocation have been proposed. Our strategy maximizes the total network utility of the best-effort users while satisfying the QoS request for maximum number of high-priority users. We approximate best-effort user utility function as a piece-wise linear function and propose a linear programming based cluster allocation algorithm. The feasibility of the resource allocation problem depends on the number of HP users in the network. Since a large number of demanding HP users would render the resource allocation problem infeasible, a joint admission control and resource allocation scheme could be an efficient way of tackling both problems with less overhead. By incorporating admission control, we propose an efficient and optimal joint admission control and resource allocation algorithm.
The most likely voltage path and large deviations approximations for integrate-and-fire neurons

We develop theory and numerical methods for computing the most likely subthreshold voltage path of a noisy integrate-and-fire (IF) neuron, given observations of the neuron’s superthreshold spiking activity. This optimal voltage path satisfies a second-order ordinary differential (Euler-Lagrange) equation which may be solved analytically in a number of special cases, and which may be solved numerically in general via a simple “shooting” algorithm. Our results are applicable for both linear and nonlinear subthreshold dynamics, and in certain cases may be extended to correlated subthreshold noise sources. We also show how this optimal voltage may be used to obtain approximations to (1) the likelihood that an IF cell with a given set of parameters was responsible for the observed spike train; and (2) the instantaneous firing rate and interspike interval distribution of a given noisy IF cell. The latter probability approximations are based on the classical Freidlin-Wentzell theory of large deviations principles for stochastic differential equations. We close by comparing this most likely voltage path to the true observed subthreshold voltage trace in a case when intracellular voltage recordings are available in vitro.
Emergence and evolution of triangular vortices

Laboratory observations and numerical simulations reveal that, in addition to monopoles, dipoles and tripoles, yet another stable coherent vortex may emerge from unstable isolated circular vortices. This new vortex is the finite-amplitude result of the growth of an azimuthal wavenumber-3 perturbation. It consists of a triangular core of single-signed vorticity surrounded by three semicircular satellites of oppositely signed vorticity. The stability of this triangular vortex is analysed through a series of high-resolution numerical simulations and by an investigation of point-vortex models. This new compound vortex rotates about its centre and is stable to small perturbations. If perturbed strongly enough, it undergoes an instability in which two of the outer satellites merge, resulting in the formation of an axisymmetric tripole, which subsequently breaks down into either a pair of dipoles or a dipole plus a monopole. The growth of higher-azimuthal-wavenumber perturbations leads to the formation of more intricate compound vortices with cores in the shape of squares, pentagons, etc. However, numerical simulations show that these vortices are unstable, which agrees with results from point-vortex models.
COUNTERINTUITIVE OUTCOMES OF INTERSPECIFIC COMPETITION BETWEEN TWO GRASSHOPPER SPECIES ALONG A RESOURCE GRADIENT

Interspecific competition has long been implicated as a force structuring the distribution of organisms along environmental gradients. The research presented here uses a survey, foraging observations, and a manipulative field experiment that test the included-niche competition hypothesis as a mechanism structuring the distribution of a generalist grasshopper, Melanoplus femurrubrum, along a food-resource gradient. A field survey of 10 old fields revealed a step-like reduction in M. femurrubrum abundance as the proportion of grass cover in the fields exceeded 60%. Furthermore, M. femurrubrum abundance and the abundance of a potential competitor, the grass specialist Chorthippus curtipennis, were negatively correlated among the fields. Experimental foraging observations showed that M. femurrubrum was a polyphagous feeder that preferred grass and consumed less grass in the presence of C. curtipennis. The pattern of grasshopper distribution and foraging data support an included-niche competition hypothesis. However, in a field experiment that manipulated C. curtipennis presence and absence and the composition of vegetation in which competition might occur, growth and mortality rates in M. femurrubrum did not respond to C. curtipennis competition. Performance was predicted to be lowest in grass-dominated conditions, those corresponding to the locations where M. femurrubrum does not exist. Instead, growth rates were highest and mortality rates were lowest in grass-only treatments. While the survey and foraging observations support the included-niche hypothesis, the experiments suggest that interspecific competition in adult grasshoppers is not the cause of the grasshopper distribution pattern. Similar experiments in western North American prairies indicate that interspecific competition can be important and that foraging ecology can be a good indicator of the interaction. This study contributes to the increasing body of knowledge about interspecific competition's role in organism distributions. It demonstrates that geographic similarity in natural history need not lead to a similar importance of limiting factors.
Electrokinetic Behavior of Aqueous Silicon Carbide Whisker Suspensions

This study examines the dispersion of SiC whiskers in the presence of a dispersing agent and coupling agents. The dispersion was examined from zeta potential measurements. The presence of sodium polyacrylate increases the zeta potential to high negative values.
Masculinity, Citizenship, and the Making of War

Citizenship is not one of the issues political scientists hotly contest.1 Yet perhaps we have failed to recognize the profoundly controversial issues involved in citizenship. One of the most difficult for the modern citizen is, of course, whether the classical ideal of "high citizenship" remains a possibility. But the ideal of ruling and being ruled will not be my concern here.2 Rather, my concern will focus on the fact that citizenship has historically been a very exclusive social category. Many groups have struggled to attain the status of citizen. In the United States to be poor, black, or female, has for the most part meant automatic disenfranchisement. Citizenship, then, concerns the question of one's position in the community of which one is a part. It is, of course, not the only determinant by far and is itself dependent on other factors. Yet given these considerations, teaching about citizenship must raise the ethical issues which, if made as prominent as they deserve to be, would indeed make citizenship the subject of controversy.
Looking for Balance

The Environmental Pendulum A Quest for the Truth about Toxic Chemicals, Human Health, and Environmental Protection. R. Allan Freeze. University of California Press, Berkeley, 2000. 337 pp. $50. ISBN 0-520-22046-3. Paper, $19.95. ISBN 0-520-22047-1. Freeze, a distinguished expert on groundwater, argues for a middle ground environmental policy against the polarization that he believes has favored the extremes of neglect and overkill.
Experimental implementation of entanglement concentration using Schmidt projection

We implement entanglement concentration by the Schmidt projection protocol, known for its optimal efficiency for large number of qubits, using photon pairs entangled in polarization and momentum and employing single-photon two-qubit quantum logic.
Thromboangiitis obliterans successfully treated with phosphodiesterase type 5 inhibitors

Thromboangiitis obliterans, or Buerger’s disease, is a non-atherosclerotic, segmental, inflammatory disease affecting the small- and medium-sized vessels of the distal extremities. Other than discontinuation of tobacco, there is no standard-of-care treatment. Although two randomized trials have demonstrated a role for intravenous iloprost, no oral drug has yet been demonstrated to be effective in treating thromboangiitis obliterans. We present the first three reported cases of thromboangiitis obliterans successfully treated with phosphodiesterase type 5 inhibitors, followed by a discussion of the rationale for the use of these agents in thromboangiitis obliterans.