Heat and Moisture Conduction in Unsaturated Soils

Mathematical models are developed for the prediction of heat transfer from hot water pipes buried in the soil. Heat transfer in the absence of moisture transfer is described as a function of the difference between the temperature of the pipe and the temperature of the soil surface. The energy balance is used to determine the longitudinal temperature distribution of the water. The method is extended to describe a system of equally spaced, parallel buried pipes. Soil temperature profiles around the pipes are presented. The model is used to calculate the land area that can be heated by an underground piping system carrying cooling water from the condensers of a 1000 MW nuclear-electric plant. A new development of the phenomenological equations for coupled heat and moisture flow, based on the theory of Irreversible Thermodynamics, is presented. Solutions of the equations for boundary conditions representative of buried piping systems designed for simultaneous soil heating and irrigation are presented

Could humans recognize odor by phonon assisted tunneling?

Our sense of smell relies on sensitive, selective atomic-scale processes that are initiated when a scent molecule meets specific receptors in the nose. However, the physical mechanisms of detection are not clear. While odorant shape and size are important, experiment indicates these are insufficient. One novel proposal suggests inelastic electron tunneling from a donor to an acceptor mediated by the odorant actuates a receptor, and provides critical discrimination. We test the physical viability of this mechanism using a simple but general model. Using values of key parameters in line with those for other biomolecular systems, we find the proposed mechanism is consistent both with the underlying physics and with observed features of smell, provided the receptor has certain general properties. This mechanism suggests a distinct paradigm for selective molecular interactions at receptors (the swipe card model): recognition and actuation involve size and shape, but also exploit other processes.Comment: 10 pages, 1 figur

Gabapentin Drug Misuse Signals: A Pharmacovigilance Assessment Using the FDA Adverse Event Reporting System

Background: Although there have been increasing reports of intentional gabapentin misuse, epidemiological evidence for the phenomenon is limited. The purpose of this study was to determine whether there are pharmacovigilance abuse signals for gabapentin.Methods: Using FDA Adverse Events Reporting System reports from January 1, 2005 to December 31, 2015, we calculated pharmacovigilance signal measures (i.e., reporting odds ratio, proportional reporting ratio, information component, and empirical Bayes geometric mean) for abuse-related adverse event (AR-AE)-gabapentin pairs. Loglinear modeling assessed the frequency of concurrent reporting of abuse-related and abusespecific AEs (AS-AEs) associated with gabapentin. Findings were compared to a positive (pregabalin) and negative (duloxetine) control.Results: From 2005-2015 there were 5,951,229 unique AE reports submitted to the FDA including 99,977 for gabapentin, 73,977 for duloxetine, and 97,813 for pregabalin. Significant drug-AR-AE pair signals involving gabapentin included: drug abuser, multiple drug overdose, and substance-induced psychotic disorder. Significant drug AR-AE signals involving gabapentin and pregabalin, but not duloxetine, were: ataxia, dependence, drug abuse, increased drug tolerance, and overdose. Compared to duloxetine, gabapentin had significantly greater odds of a coreport for an AS-AE with drug withdrawal syndrome (OR: 6.55), auditory hallucinations (OR: 4.57), delusions (OR: 2.36), euphoric mood (OR: 5.45), ataxia (OR: 2.85), drug abuser (OR: 3.01), aggression (OR: L98), psychotic disorder (OR: 1.96), and feeling abnormal (OR: 1.31).Conclusions: We identified abuse-related signals for gabapentin and highlighted several CNS effects that may be associated with its abuse. Gabapentin prescribers should be aware of the drug\u27s abuse liability and effects that may accompany its use

Will HIV Vaccination Reshape HIV Risk Behavior Networks? A Social Network Analysis of Drug Users\u27 Anticipated Risk Compensation

Background An HIV vaccine could substantially impact the epidemic. However, risk compensation (RC), or post-vaccination increase in risk behavior, could present a major challenge. The methodology used in previous studies of risk compensation has been almost exclusively individual-level in focus, and has not explored how increased risk behavior could affect the connectivity of risk networks. This study examined the impact of anticipated HIV vaccine-related RC on the structure of high-risk drug users\u27 sexual and injection risk network. Methods A sample of 433 rural drug users in the US provided data on their risk relationships (i.e., those involving recent unprotected sex and/or injection equipment sharing). Dyad-specific data were collected on likelihood of increasing/initiating risk behavior if they, their partner, or they and their partner received an HIV vaccine. Using these data and social network analysis, a post-vaccination network was constructed and compared to the current network on measures relevant to HIV transmission, including network size, cohesiveness (e.g., diameter, component structure, density), and centrality. Results Participants reported 488 risk relationships. Few reported an intention to decrease condom use or increase equipment sharing (4% and 1%, respectively). RC intent was reported in 30 existing risk relationships and vaccination was anticipated to elicit the formation of five new relationships. RC resulted in a 5% increase in risk network size (n = 142 to n = 149) and a significant increase in network density. The initiation of risk relationships resulted in the connection of otherwise disconnected network components, with the largest doubling in size from five to ten. Conclusions This study demonstrates a new methodological approach to studying RC and reveals that behavior change following HIV vaccination could potentially impact risk network connectivity. These data will be valuable in parameterizing future network models that can determine if network-level change precipitated by RC would appreciably impact the vaccine\u27s population-level effectiveness

Record RF performance of standard 90 nm CMOS technology

We have optimized 3 key RF devices realized in standard logic 90 nm CMOS technology and report a record performance in terms of n-MOS maximum oscillation frequency f/sub max/ (280 GHz), varactor tuning range and varactor and inductor quality factor

Mitigating cyanobacterial harmful algal blooms in aquatic ecosystems impacted by climate change and anthropogenic nutrients

Mitigating the global expansion of cyanobacterial harmful blooms (CyanoHABs) is a major challenge facing researchers and resource managers. A variety of traditional (e.g., nutrient load reduction) and experimental (e.g., artificial mixing and flushing, omnivorous fish removal) approaches have been used to reduce bloom occurrences. Managers now face the additional effects of climate change on watershed hydrologic and nutrient loading dynamics, lake and estuary temperature, mixing regime, internal nutrient dynamics, and other factors. Those changes favor CyanoHABs over other phytoplankton and could influence the efficacy of control measures. Virtually all mitigation strategies are influenced by climate changes, which may require setting new nutrient input reduction targets and establishing nutrient-bloom thresholds for impacted waters. Physical-forcing mitigation techniques, such as flushing and artificial mixing, will need adjustments to deal with the ramifications of climate change. Here, we examine the suite of current mitigation strategies and the potential options for adapting and optimizing them in a world facing increasing human population pressure and climate change

Critical parameters for electron beam curing of cationic epoxies and property comparison of electron beam cured cationic epoxies versus thermal cured resins and composites

Electron beam curing of composites is a nonthermal, nonautoclave curing process offering the following advantages compared to conventional thermal curing: substantially reduced manufacturing costs and curing times; improvements in part quality and performance; reduced environmental and health concerns; and improvements in material handling. In 1994 a Cooperative Research and Development Agreement (CRADA), sponsored by the Department of Energy Defense Programs and 10 industrial partners, was established to advance electron beam curing of composites. The CRADA has successfully developed hundreds of new toughened and untoughened resins, offering unlimited formulation and processing flexibility. Several patent applications have been filed for this work. Composites made from these easily processable, low shrinkage material match the performance of thermal cured composites and exhibit: low void contents comparable to autoclave cured composites (less than 1%); superb low water absorption values in the same range as cyanate esters (less than 1%); glass transition temperatures rivaling those of polyimides (greater than 390 C); mechanical properties comparable to high performance, autoclave cured composites; and excellent property retention after cryogenic and thermal cycling. These materials have been used to manufacture many composite parts using various fabrication processes including hand lay-up, tow placement, filament winding, resin transfer molding and vacuum assisted resin transfer molding

Hidden spin-current conservation in 2d Fermi liquids

We report the existence of regimes of the two dimensional Fermi liquid that show unusual conservation of the spin current and may be tuned by varying some parameter like the density of fermions. We show that for reasonable models of the effective interaction the spin current may be conserved in general in 2d, not only for a particular regime. Low temperature spin waves propagate distinctively in these regimes and entirely new ``spin-acoustic'' modes are predicted for scattering-dominated temperature ranges. These new high-temperature propagating spin waves provide a clear signature for the experimental search of such regimes.Comment: 4 pages, no figures, revised version, accepted for pub. in the PR

The genome of ε15, a serotype-converting, Group E1 Salmonella enterica-specific bacteriophage

AbstractThe genome sequence of the Salmonella enterica serovar Anatum-specific, serotype-converting bacteriophage ε15 has been completed. The nonredundant genome contains 39,671 bp and 51 putative genes. It most closely resembles the genome of φV10, an Escherichia coli O157:H7-specific temperate phage, with which it shares 36 related genes. More distant relatives include the Burkholderia cepacia-specific phage, BcepC6B (8 similar genes), the Bordetella bronchiseptica-specific phage, BPP-1 (8 similar genes) and the Photobacterium profundum prophage, P Pφpr1 (6 similar genes).ε15 gene identifications based on homologies with known gene families include the terminase small and large subunits, integrase, endolysin, two holins, two DNA methylase enzymes (one adenine-specific and one cytosine-specific) and a RecT-like enzyme. Genes identified experimentally include those coding for the serotype conversion proteins, the tail fiber, the major capsid protein and the major repressor. ε15's attP site and the Salmonella attB site with which it interacts during lysogenization have also been determined