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Tenofovir diphosphate (TFVdp; an active metabolite of oral HIV pre-exposure prophylaxis [PrEP]) is measured in dried blood spots (DBS) to estimate adherence. However, TFVdp's long half-life in whole blood may lead to misclassification following a recent change in adherence. PrEP's other metabolite, emtricitabine triphosphate (FTCtp), has a shorter half-life in whole blood but adherence thresholds are undefined. We characterized DBS TFVdp and FTCtp concentrations across many dosing scenarios. Population PK models were fit to TFVdp and FTCtp DBS concentrations from a directly observed therapy study (NCT03218592). Concentrations were simulated for 90 days of daily dosing followed by 90 days of 1 to 7 doses/week and for event-driven PrEP (edPrEP) scenarios. Thresholds of 1000 and 200 fmol/punch, for TFVdp and FTCtp, respectively, were reflective of taking 4 doses/week (a minimum target for effective PrEP in men). TFVdp was1000 fmol/punch for 17 days after initiating daily PrEP and1000 fmol/punch for 62 days after decreasing to 3 doses/week. Respectively, FTCtp was200 fmol/punch for 4 days and200 fmol/punch for 6 days. Accuracy of edPrEP adherence classification depended on duration between last sex act and DBS sampling for both measures with misclassification ranging from 9-100%. These data demonstrate adherence misclassification by DBS TFVdp for 2 months following a decline in adherence, elucidating the need for FTCtp to estimate recent adherence. We provide proof of principle that individualized interpretation is needed to support edPrEP adherence monitoring. Our collective approach facilitates clinicians' ability to interpret DBS results and administer patient-centric interventions.

Background The trematode parasite Schistosoma mansoni uses an aquatic snail intermediate and a vertebrate definitive host to complete its life cycle. We previously showed that a key transmission trait—the number of cercariae larvae shed from infected Biomphalaria spp. snails—varies significantly within and between different parasite populations and is genetically controlled by five loci. We investigated the hypothesis that the success of parasite genotypes showing high propagative fitness in the intermediate snail host may be offset by lower reproductive fitness in the definitive vertebrate host. Methods We investigated this trade-off hypothesis by selecting parasite progeny producing high or low number of larvae in the snail and then comparing fitness parameters and virulence in the rodent host. We infected inbred BALB/c mice using two Schistosoma mansoni parasite lines [high shedder (HS) and low shedder (LS) lines] isolated from F2 progeny generated by genetic crosses between SmLE (HS parent) and SmBRE (LS parent) parasites. We used the F3 progeny to infect two populations of inbred Biomphalaria glabrata snails. We then compared life history traits and virulence of these two selected parasite lines in the rodent host to understand pleiotropic effects of genes determining cercarial shedding in parasites infecting the definitive host. Results HS parasites shed high numbers of cercariae, which had a detrimental impact on snail physiology (measured by laccase-like activity and hemoglobin rate), regardless of the snail genetic background. In contrast, selected LS parasites shed fewer cercariae and had a lower impact on snail physiology. Similarly, HS worms have a higher reproductive fitness and produced more viable F3 miracidia larvae than LS parasites. This increase in transmission is correlated with an increase in virulence toward the rodent host, characterized by stronger hepato-splenomegaly and hepatic fibrosis. Conclusions These experiments revealed that schistosome parasite propagative and reproductive fitness was positively correlated in intermediate and definitive host (positive pleiotropy). Therefore, we rejected our trade-off hypothesis. We also showed that our selected schistosome lines exhibited low and high shedding phenotype regardless of the intermediate snail host genetic background. ​ Graphical Abstract

Sequence variation among antigenicvargenes enablesPlasmodium falciparummalaria parasites to evade host immunity. Using long sequence reads from haploid clones from a mutation accumulation experiment, we detectvardiversity inconsistent with simple chromosomal inheritance. We discover putatively circular DNA that is strongly enriched forvargenes, which exist in multiple alleles per locus separated by recombination and indel events. Extrachromosomal DNA likely contributes to rapid antigenic diversification inP. falciparum.

Aquatic snails, the intermediate hosts of schistosomes, harbor a diverse unexplored microbiome. We speculate that this may play a critical role in host-parasite interactions. We summarize our current knowledge of snail microbiomes and highlight future research priorities.

A treatment gap exists for pediatric patients with renal impairment. Alterations in renal clearance and metabolism of drugs render standard dosage regimens inappropriate and may lead to drug toxicity, but these studies are not routinely conducted during drug development. The objective of this study was to examine the clinical evidence behind current renal impairment dosage recommendations for pediatric patients in a standard pediatric dosing handbook. The sources of recommendations and comparisons included the pediatric dosing handbook (Lexicomp), the U.S. Food and Drug Administration-approved manufacturer’s labels, and published studies in the literature. One hundred twenty-six drugs in Lexicomp had pediatric renal dosing recommendations. Only 14% (18 of 126) of Lexicomp pediatric renal dosing recommendations referenced a pediatric clinical study, and 15% of manufacturer’s labels (19 of 126) described specific dosing regimens for renally impaired pediatric patients. Forty-two products had published information on pediatric renal dosing, but 19 (45%) were case studies. When pediatric clinical studies were not referenced in Lexicomp, the renal dosing recommendations followed the adult and pediatric dosing recommendations on the manufacturer’s label. Clinical evidence in pediatric patients does not exist for most renal dosing recommendations in a widely used pediatric dosing handbook, and the adult renal dosing recommendations from the manufacturer’s label are currently the primary source of pediatric renal dosing information.

In 2005 Richard Carter's group surprised the malaria genetics community with an elegant approach to rapidly mapping the genetic basis of phenotypic traits in rodent malaria parasites. This approach, which he termed "linkage group selection", utilized bulk pools of progeny, rather than individual clones, and exploited simple selection schemes to identify genome regions underlying resistance to drug treatment (or other phenotypes). This work was the first application of "bulk segregant" methodologies for genetic mapping in microbes: this approach is now widely used in yeast, and across multiple recombining pathogens ranging from Aspergillus fungi to Schistosome parasites. Genetic crosses of human malaria parasites (for which Richard Carter was also a pioneer) can now be conducted in humanized mice, providing new opportunities for exploiting bulk segregant approaches for a wide variety of malaria parasite traits. We review the application of bulk segregant approaches to mapping malaria parasite traits and suggest additional developments that may further expand the utility of this powerful approach.

Despite development of modern antiretrovirals with lower drug interaction potential than their predecessors, drug interaction challenges remain. Standard treatment regimens still require multiple antiretrovirals that may cause, or may be the target of, drug interactions. Additionally, people living with HIV are living longer and often present with comorbid conditions that require concomitant long-term drug therapy. Also, treatment of infectious diseases in resource-limited settings can result in significant interactions. In this review, we describe absorption, distribution, metabolism, and excretion pathways as they relate to relevant drug interactions with antiretrovirals along with the potential clinical consequences of these interactions. We highlight clinical data that illustrate pertinent interactions and provide tools to assist in predicting drug interactions in the absence of clinical data. Given these tools and thoughtful consideration of drug combinations, drug therapy in people living with HIV can be safely and effectively managed throughout their lifetime.

The microservice-based architecture – a SOA-inspired principle of dividing systems into components that communicate with each other using language-agnostic APIs – has gained increased popularity in industry. Yet, migrating a monolithic application to microservices is a challenging task. A number of automated microservice extraction techniques have been proposed to help developers with the migration complexity. These techniques, at large, construct a graph-based representation of an application and cluster its elements into service candidates. The techniques vary by their decomposition goals and, subsequently, types of relationships between application elements that they consider – structural, semantic term similarity, and evolutionary – with each technique utilizing a fixed subset and weighting of these relationship types.In this paper, we perform a multi-method exploratory study with 10 industrial practitioners to investigate (1) the applicability and usefulness of different relationships types during the microservice extraction process and (2) expectations practitioners have for tools utilizing such relationships. Our results show that practitioners often need a "what-if" analysis tool that simultaneously considers multiple relationship types during the extraction process and that there is no fixed way to weight these relationships. Our study also identifies organization- and application-specific considerations that lead practitioners to prefer certain relationship types over others, e.g., the age of the codebase and languages spoken in the organization. It outlines possible strategies to help developers during the extraction process, e.g., the ability to iteratively filter and customize relationships.

Off-target drift during pesticide spray applications represents a potential pathway for the introduction of active ingredient into field-adjacent water, soils, and/or vegetation. This study investigated the extent of downwind spray drift deposition of thiamethoxam (as a model insecticide) from an application of Actara® 25WG using standard nozzles (TeeJet XR11003, DG11004, and AIXR11002) onto a fallow field test site in the Midwestern USA. Single broadcast applications at a target rate of 96 g a.i./ha were made uniformly via tractor boom to a mowed stubble plot at a spray volume of 93.5 L/ha. Sampling devices (stainless steel disks, filter paper, and stainless steel rods) were located upwind of the spray swath (as negative control samples), within the spray swath (filter paper only), and downwind (all samplers), perpendicular to the spray swath from 12.5 to 400 ft. (3.8 to 122 m) from the edge of the treated field. Comparison of measured residues from the three types of samplers indicated that filter paper generally had greater variability in results than metal disks. When nozzles were compared, the AIXR11002 air induction nozzle produced less off-field deposition than other nozzles tested. Measured downwind concentrations of thiamethoxam from disk samplers were used to predict distances for mitigating potential effects to honey bees. Based on field-derived models, downwind distances from the spray swath required to reduce exposure levels below levels of concern for honey bees varied from1 ft. to 148 ft. (0.3 to 45 m) depending on the hazard endpoint and nozzle used. These distances were considerably lower than those predicted using the AgDRIFT model, particularly for distances further downwind. At 400 ft. (122 m), AgDRIFT over-predicted the calculated concentrations by up to a factor of 4.8, 7.2, and 10 for DG11004, XR11003, and AIXR11002, respectively. These data suggest that the AgDRIFT model is less reliable for predicting spray deposition at further downwind distances, with implications for risk assessment.

Schistosoma mansoni is the causative agent of intestinal schistosomiasis and infects ~54 million people annually, causing significant mortality and morbidity. This parasitic trematode is endemic in sub-Saharan Africa and the Middle East, and colonized South America during the transatlantic slave trade. Parasites transition between five distinctive body plans, with asexual proliferation in the snail host and sexual proliferation in the vertebrate host, and motile free-living stages. Transmission results from contact with water containing infected Biomphalaria spp. snails. Infection prevalence and intensity peaks in school age children: both reduced water contact and acquired immunity reduces infection in adults. Pathology to the human host results from granulomas that form around eggs trapped in the liver and gut. These is no effective vaccine available: treatment of infected patients with praziquantel is the mainstay of control efforts.

Background Tracking and understanding artemisinin resistance is key for preventing global setbacks in malaria eradication efforts. The ring-stage survival assay (RSA) is the current gold standard for in vitro artemisinin resistance phenotyping. However, the RSA has several drawbacks: it is relatively low throughput, has high variance due to microscopy readout, and correlates poorly with the current benchmark for in vivo resistance, patient clearance half-life post-artemisinin treatment. Here a modified RSA is presented, the extended Recovery Ring-stage Survival Assay (eRRSA), using 15 cloned patient isolates from Southeast Asia with a range of patient clearance half-lives, including parasite isolates with and without kelch13 mutations. Methods P. falciparum cultures were synchronized with single layer Percoll during the schizont stage of the erythrocytic cycle. Cultures were left to reinvade to early ring-stage and parasitemia was quantified using flow cytometry. Cultures were diluted to 2% hematocrit and 0.5% parasitemia in a 96-well plate to start the assay, allowing for increased throughput and decreased variability between biological replicates. Parasites were treated with 700nM of dihydroartemisinin or an equivalent amount of dimethyl sulfoxide (DMSO) for 6 h, washed three times in drug-free media, and incubated for 66 or 114 h, when samples were collected and frozen for PCR amplification. A SYBR Green-based quantitative PCR method was used to quantify the fold-change between treated and untreated samples. Results 15 cloned patient isolates from Southeast Asia with a range of patient clearance half-lives were assayed using the eRRSA. Due to the large number of pyknotic and dying parasites at 66 h post-exposure (72 h sample), parasites were grown for an additional cell cycle (114 h post-exposure, 120 h sample), which drastically improved correlation with patient clearance half-life compared to the 66 h post-exposure sample. A Spearman correlation of 0.8393 between fold change and patient clearance half-life was identified in these 15 isolates from Southeast Asia, which is the strongest correlation reported to date. Conclusions eRRSA drastically increases the efficiency and accuracy of in vitro artemisinin resistance phenotyping compared to the traditional RSA, which paves the way for extensive in vitro phenotyping of hundreds of artemisinin resistant parasites.

Several cases of failure due to rupture of reinforcing bars in RC buildings were reported by inspection teams after the 2010 Muale earthquake in Chile that triggered further research efforts. This paper studies the effect of long-duration earthquakes on the damage potential due to low-cycle fatigue through nonlinear analysis of three existing RC frame buildings. The number of strain cycles and their amplitudes for reinforcing bars at the critical locations within each building were obtained from nonlinear time history analyses. The reduction in the fatigue life has been estimated using S-N curve obtained from the experimental literature and by applying the Palmgren-Miner damage rule. The results showed significant reduction in fatigue life for the low- and medium-rise buildings larger than high-rise buildings. It was found that A706 steel has longer fatigue life than A615 steel. Also, larger diameter steel bars tend to experience less fatigue damage within RC members.

The neocortex forms a single sheet that is subdivided into 100 or more different functional areas in primates. One unifying concept is that the local circuits in the neocortex share the same basic organization and that the functional differences between cortical areas arise from differences in their afferent input—both from subcortical regions like the thalamus and other regions of neocortex. While investigations in the macaque monkey have provided us with the most complete and quantitative map of the interareal connections for any species, our knowledge of the organization of synaptic connections of these interareal pathways is still quite incomplete. We have investigated the macaque visual cortex in search of the design principles of the synaptic relationships formed by long-distance interareal projections. The pyramidal cells, which form the interareal projections, contribute only a tiny fraction of all the extrinsic excitatory synapses in a given target area. One lamina is the principal target, but frequently the axons form synapses in a secondary lamina. Most interareal synapses are formed with the spines of pyramidal cells. The GABAergic smooth cell dendrites constitute 0–20% of the target population. To explain why the tiny numbers of excitatory synapses that connect two areas are so effective, we suggest that the local recurrent circuit amplifies spatio-temporal patterns of excitation generated by long-distance connections—both thalamic and interareal. The specific computations within an area are a consequence of specific patterns of excitatory input from the long-distance projections that are shaped by excitatory and inhibitory activity evoked in the local circuit.

“Synthesis & Application of Labelled Compounds 2002” Isotopes and Mass Spectrometry Carbon-13 Labelling to Aid the Development of the Catalytic Alkenation of Carbonyls Production and Applications of 124I for Positron Emission Tomography Organic Photochemistry: Synthetic Approaches to Alkaloids in a Reagentless Environment Fluorinaion for Positron Emission Tomography Synthetic Consequences of Kinetic Isotopes Effects: Synthesis of [13 C6]-SR31742A For Human Trail Purposes Tritio-Dehalogenation: New Variants on an Old Theme The Synthesis of BOC-L-Proline-[14C2] Benzyl Ester Peptide Labelling with Fluorine-18

Anorexia nervosa (AN) is a complex and heritable eating disorder characterized by dangerously low body weight. Neither candidate gene studies nor an initial genome-wide association study (GWAS) have yielded significant and replicated results. We performed a GWAS in 2907 cases with AN from 14 countries (15 sites) and 14 860 ancestrally matched controls as part of the Genetic Consortium for AN (GCAN) and the Wellcome Trust Case Control Consortium 3 (WTCCC3). Individual association analyses were conducted in each stratum and meta-analyzed across all 15 discovery data sets. Seventy-six (72 independent) single nucleotide polymorphisms were taken forward for in silico (two data sets) or de novo (13 data sets) replication genotyping in 2677 independent AN cases and 8629 European ancestry controls along with 458 AN cases and 421 controls from Japan. The final global meta-analysis across discovery and replication data sets comprised 5551 AN cases and 21 080 controls. AN subtype analyses (1606 AN restricting; 1445 AN binge-purge) were performed. No findings reached genome-wide significance. Two intronic variants were suggestively associated: rs9839776 (P = 3.01 × 10-7) in SOX2OT and rs17030795 (P = 5.84 × 10-6) in PPP3CA. Two additional signals were specific to Europeans: rs1523921 (P = 5.76 × 10-6) between CUL3 and FAM124B and rs1886797 (P = 8.05 × 10-6) near SPATA13. Comparing discovery with replication results, 76% of the effects were in the same direction, an observation highly unlikely to be due to chance (P = 4 × 10-6), strongly suggesting that true findings exist but our sample, the largest yet reported, was underpowered for their detection. The accrual of large genotyped AN case-control samples should be an immediate priority for the field. © 2014 Macmillan Publishers Limited All rights reserved.

A prototype meal bar of extruded sorghum-peanut wafer with filling and enrobing was subjected to accelerated shelf-life testing at 60°C for 4 wks Samples were withdrawn each week for analyses including slurry pH, Kramer shear texture measures, CIE L*a*b* color, water activity, peroxide values, malonaldehyde content, available lysine, and proximate composition. Principal factor analysis with varimax rotation was used to assess associations of related factors. Six factors accounted for 77.5% of variance. Significant changes occurred with respect to the control over 4 wk storage, particularly in a sharp reduction of pH, and increased pigmentation. Other measures were minimally changed.

Two shear wall specimens loaded for experimental testing at the University of California, Berkeley, were modeled using the ADINA Nonlinear Finite Element Concrete Material Model with plane stress isoparametric finite elements. Force vs displacement results show good correlation with the experimental data. The models were loaded with monotonically increasing static loads. The analyses give an estimate of the displacement ductility available in shear walls. Using this technique, finite element modeling can be used for future structural applications to design for greater displacement ductility.

This paper reports on the authors' efforts to improve the small farm community welfare in Kenya by promoting biogas technology. The survey showed that fuel was used in Kenyan farms mainly for cooking and lighting, and wood, crop residue, and charcoal were the predominant fuel sources. Mostly women collected firewood, fetched water, and cooked. Building a fire with these fuels was time-consuming, and smoke from these fires was damaging to the living environment. Hence, applying biogas technology to Kenyan small farms not only guarantees a reliable, renewable energy source, but also provides other benefits, such as cleaner household environments, better working conditions for housewives

An adaptive method for the on-line identification of hysteretic structures under arbitrary dynamic environments is presented. In spite of the challenges encountered in the identification of the hereditary nature of the restoring force of hysteretic systems, it is shown that the proposed approach can yield reliable estimates of the hysteretic restoring force under a wide range of excitation levels and response ranges. The proposed method is verified through simulation studies and experimental tests conducted on a full-scale structural steel subassembly.

Thermal systems are an important segment of engineering design, but practical, realistic laboratory models are not plentiful. There are some educational oriented systems models, but these are expensive and typically the design details of the machine are not furnished with the purchase of the equipment, making deviation from the original intent of the equipment difficult. This paper describes the development of a small, portable, and inexpensive system that allows students a wide range of educational experiences. Students may study the overall design and construction of the system, selection and cost of components, and the effect of different control schemes. The laboratory apparatus is built around an industry standard, low cost PLC. The control scheme may be changed from a simple OFF-ON control to a PID loop by a software routine on the PLC. Heating and sensing devices are those used typically in plastics manufacturing equipment and the controlled device may be varied to simulate the effect of process conditions and raw material on the thermal control system. Data logging is available to allow students to record and observe the system effect of process changes. The apparatus may be fabricated at a low cost (under $500), is small in size and portable, and may be powered from available single phase AC voltage. This has important implications in programs where lab space or funding is an issue, and also may be integrated into distance education programs. Examples of integration into courses are addressed.

This fifth edition of a successful textbook continues to provide students with an introduction to the basic principles of materials science over a broad range of topics. The authors have revised and updated this edition to include many new applications and recently developed materials.The book is presented in three parts. The first section discusses the physics, chemistry, and internal structure of materials. The second part examines the mechanical properties of materials and their application in engineering situations. The final section presents the electromagnetic properties of materials and their application. Each chapter begins with an outline of the relevance of its topics and ends with problems that require an understanding of the theory and some reasoning ability to resolve. These are followed by self-assessment questions, which test students' understanding of the principles of materials science and are designed to quickly cover the subject area of the chapter.This edition of Materials Science for Engineers includes an expanded treatment of many materials, particulary polymers, foams, composites and functional materials. Of the latter, superconductors and magnetics have received greater coverage to account for the considerable development in these fields in recent years. New sections on liquid crystals, superalloys, and organic semiconductors have also been added to provide a comprehensive overview of the field of materials science.

One of problems associated with project courses is the short time available to complete the course. This typically limits the project to a segment of the total manufacturing design cycle. For a manufacturing project such as that to produce a plastic part, this translates to doing the product design or the tooling design, but not both. This paper describes an innovative approach to the problem using the injection molding process as an example of a manufacturing process. Students use commercial solid modeling software to do the product design of a fairly simple part, for example a golf divot tool. The product design is then used to develop tooling (molds), to simulate structural performance and molding characteristics, and generate the NC code to machine the tooling. Once the tooling is finished it is placed on a lab injection molder and the process is tested and optimized. The entire lab experience is completed in approximately 30 hours of laboratory time, The equipment and software used to complete the project are typical of that available in undergraduate engineering facilities.

There has been much research done in methods for shortening the time required to design and build tooling for plastic molding processes. While the more exotic procedures, such as stereo lithography have gotten much attention, there continues to be advancement in the areas of modeling, simulation, and numerical control that allow a very short cycle between product design and manufacturing. Use of this technology has allowed commercial mold makers to compress the delivery of production molds from several weeks to less than 48 hours. This paper describes the implementation of a rapid tooling program at Purdue University. Students with an introductory course in solid modeling learn the specialized application software and apply it to projects in a normal semester time frame. This allows students to learn the process, learn the practical aspects of design for manufacturing, and learn the benefits of modeling and simulation in a realistic setting.

The performance and costs of three types of cryogenic cooling systems are analyzed; a once-through system in which liquid nitrogen is allowed to boil on the CPU boards and is then vented to the surroundings; a saturated pool boiling refrigerated system in which gaseous nitrogen generated from boiling on the CPU boards in condensed in the vapor space above the liquid nitrogen pool; and a subcooled pool boiling refrigerated system in which the condenser is completely submerged in a subcooled liquid nitrogen pool surrounding the CPU boards. Thermal/fluid numerical models used in conjunction with an optimization code GRG2, were used to predict the performance and cost of the cryogenic cooling systems. The uniform annual cost of the once-through system was calculated to be $28.8 K. This compares with $34.6 K for the optimal saturated pool boiling system and $34.7 K for the optimal subcooled pool boiling system. Due to the extremely high initial cost of the refrigerated systems, the once-through cryogenic cooling system is recommended if the local heat flux on the CPU board remains below 15 W/cm/sup 2/. >

Spectral magnitude analysis can be performed with identical results by computing the short-time Fourier transform magnitude ( mod STFT mod ) of a real signal, or by analyzing the signal with a filter/detector (F/D) bank. In the latter approach, analysis is performed by a bank of bandpass filters, each of which is followed by a detector consisting of a square law device. The equivalence between mod STFT mod and F/D bank analysis is extended to complex signals. New applications such as complex signal reconstruction from spectral magnitude and pulse-Doppler radar signal processors are discussed. A new equivalence between wavelet analysis and the generalized STFT is presented, and it is shown that speech spectrograms are not equivalent to the mod STFT mod . >

A complex sequence can be recovered to within an overall constant phase factor from its generalized short-time Fourier transform magnitude, which includes the wavelet scalogram and short-time Fourier transform magnitude as special cases. >

The authors report on an experiment to verify the accuracy of reject ratio predictions by the available approaches. The data collection effort includes instrumenting the wafer probe test to obtain chip failures as a function of applied vectors and running a fault simulator to obtain the cumulative fault coverage of these vectors. The accuracy of reject ratio predictions is judged by assuming earlier stopping points for the wafer probe, thereby gaining a measure of confidence in the final predicted value. The results of five different analyses are reported for over 70000 tested dies of a CMOS VLSI device. The five methods discussed predicted values for the reject ratio that vary by an order of magnitude at high values of fault coverage. It is shown that, with only an incremental effort during wafer probe, data collection that can be used to compare the relative accuracy of different models over a range of fault coverage is possible. >

The Department of Defense ARPA program for Rapid Prototyping of Application Specific Signal Processors (RASSP) exists to significantly improve the process by which embedded digital signal processors are developed (prototyped) and supported (maintained and upgraded). As used in the RASSP program, the term prototype signifies a system that is a precursor to a deployed system, but still meets all of the essential performance goals and is designed to facilitate maintainability and upgradability. Current practice in the design of embedded digital signal processors, as exemplified in the traditional waterfall design methodology, is examined and shortfalls in the design, methodology and supporting tools are identified. Opportunities for improving the traditional design practice are then identified and evaluated in terms of potential benefits, as well as impediments, to implementation, and adoption by the community.

This paper describes the development of a tool to help students easily visualize stresses in truss structures through photoelastic visualization of quickly assembled truss structures. Clear polymer structural members of varying lengths were designed with the capability to be connected to form a variety of simple truss structures. This development effort was conducted across functional areas in a mechanical engineering technology department. Eventually, a fully developed mechanical toolkit will be used in conjunction with computational and numerical tools in the study of stress, strain, and strength analysis as well as offering a platform to teach instrumentation techniques in experimental stress analysis.

This paper reports on experimental studies that were conducted to test the inelastic, cyclic behavior on four repair/upgrade details which have been suggested for welded beam to column moment connections. These details are shown to provide varying degrees of improvement in connection behavior with plastic rotation capacities between two percent and four percent being achieved.

The wavelet transform is a special case of the generalized short-time Fourier transform (GSTFT), which predates wavelet analysis by many years. The theorem presented here is one example of how GSTFT research can be beneficially applied to wavelet analysis. >

We describe a sensitive high-performance liquid chromatographic method for the determination of 5-aminosalicylic acid and N-acetyl-5-aminosalicylic acid in rectal tissue biopsies. Samples were derivatised using propionic anhydride and proteins were precipitated with methanol. A Supelcosil ABZ column (150x4.6 mm I.D., 5 microm silica particles) was used with a mobile phase comprising 0.1 M acetic acid, acetonitrile and triethylamine (1600:114:6, v/v/v). Fluorescence detection was employed and detection limits were 0.2 ng/mg tissue at a signal-to-noise ratio of three (measured concentration: 5-aminosalicylic acid, 0.254 (0.228-0.286) ng/mg, C.V. 10.7%; N-acetyl-5-aminosalicylic acid, 0.18 (0.154-0.198) ng/mg, C.V 9.8%). This assay was validated for use with serum, urine and faecal samples for which it proved to be both precise and accurate (C.V.

Transportation System Risk Assessments (TSRAs) document the compliance of proposed shipments of nuclear components with applicable federal regulations as well as the associated risks involved. If a relatively simple bounding analysis can show that the consequences resulting from a worst case scenario are acceptably low, a more time intensive and costly risk analysis can be avoided. Therefore, a bounding release FORTRAN model has been developed to determine the consequences of a worst case non-criticality transportation accident. The consequences of three conservative bounding accidents are determined by the model: (1) direct radiation exposure, (2) airborne release of radiological and/or hazardous solid material, and (3) release of radiological and/or hazardous solid material into a waterway and subsequent uptake by an individual through drinking water. Program output includes the direct radiation exposure (mrem), maximum downwind concentration (mg/m{sup 3}), radiation dose (mrem) received as a result of the postulated airborne release of radiological material, intake (mg) due to inhalation, radiation dose (mrem) received by an individual resulting from a release of radiological material into a waterway and uptake into drinking water, and uptake (mg) due to ingestion. This report documents the methodologies and correlations used in the numerical model to perform the bounding consequence calculations.

Producibility problems, such as low reservoir pressure and reservoir heterogeneity, have severely limited oil production from the Central Bluff and North Fairview fields. Specific objectives for this project were: To successfully apply detailed geologic and engineering studies with conventional waterflood technologies to these fields in an effort to increase the ultimate economic recovery of oil from Carter sandstone fields; To extensively model, test and evaluate these technologies; thereby, developing a sound methodology for their use and optimization; and To team with Advanced Resources International and the US DOE to assimilate and transfer the information and results gathered from this study to other oil companies to encourage the widespread use of these technologies. At Central Bluff, water injection facilities were constructed and water injection into one well began in January 1993. Oil response from the waterflood has been observed at both producing wells. One of the producing wells has experienced early water breakthrough and a concomitant drop in secondary oil rate. A reservoir modeling study was initiated to help develop an appropriate operating strategy for Central Bluff. For the North Fairview unit waterflood, a previously abandoned well was converted for water injection which began in late June 1993. The reservoir ismore » being re-pressurized, and unit water production has remained nil since flood start indicating the possible formation of an oil bank. A reservoir simulation to characterize the Carter sand at North Fairview was undertaken and the modeling results were used to forecast field performance. The project was terminated due to unfavorable economics. The factors contributing to this decision were premature water breakthrough at Central Bluff, delayed flood response at North Fairview and stalled negotiations at the South Bluff site.« less

Transient heat transfer/stress analysis models are currently being developed to evaluate the response of cylinders containing uranium hexafluoride (UF{sub 6}) to fire accident scenarios. In order to accurately predict temperatures within the cylinder, and ultimately elapsed time to failure, the heat transfer to and within the cylinder must be well characterized. This report contains a complete set of heat transfer correlations required for such a model. Correlations are presented for predicting heat transfer rates over the cylinder exterior (radiative exchange and natural convection), from the cylinder interior to the various phases of UF{sub 6} (solid, liquid, and vapor) in the cylinder, between UF{sub 6} phases in the cylinder, and during UF{sub 6} liquid boiling. The heat transfer coefficients predicted by these correlations were chosen based on best engineering judgement and have not yet been compared to data from actual cylinder fire tests.

In this Class I PON, Anderman/Smith Operating Company is targeting three Carter sandstone oilfields (Black Warrior basin) for secondary recovery. Waterfloods are underway in two of the areas -- Central Bluff and North Fairview units. For the third area, South Bluff, negotiations are underway to unitize the field. Once South Bluff is unitized, waterflooding will commence.

Anderman/Smith Operating Co. is operating a secondary oil recovery project involving the Carter sandstone in northwest Alabama. The project objectives are: (1) to increase the ultimate economic recovery of oil from the Carter reservoirs, thereby increasing domestic reserves and lessening US dependence on foreign oil; (2) to extensively model, test, and monitor the reservoirs so their management is optimized; and (3) to assimilate and transfer the information and results gathered to other US oil companies to encourage them to attempt similar projects. As a result of waterflood operations at the Central Buff unit, oil production from the Fowler Brasher 7--9 well increased to 40--50 stb/d in late October, and averaged about 45 stb/d in November with no measurable water production. Production at the Fowler Dodson 8--12 was more erratic during the same period. In October, the oil rate for this well increased to nearly 17 stb/d with no reported water production. However, in November the oil production rate declined to about 9 stb/d with an associated average water rate of nearly 17 bpd. Water analysis showed that this produced water was significantly fresher than the connate water produced prior to waterflood operations. This provides evidence for early breakthrough of water more » injected at the Jones 7--16 well and will be an important consideration in the reservoir modeling study being performed for the unit. There has been essentially no change in the waterflood response at the North Fairview Unit during the last quarter. Oil production rates from the three producing wells have remained unchanged; that is, 3 stb/d for Smith 33-6, 2 stb/d for Perkins 33--11, and 1 stb/d for the Perkins Young 33--10 well. « less

1. 1. The proteoglycan peak from anion exchange chromatography of an extract of bovine aorta was digested with chondroitinase ABC. The residual heparan sulphate proteoglycans were further purified by chromatography on Sepharose CL4B and DEAE-Sephacel to yield two species, of high and low charge density. 2. 2. Higher molecular weight material had a higher proportion of high charge density proteoglycan, while the lower molecular weight species had a higher proportion of low charge density heparan sulphate proteoglycan. 3. 3. The two species shared epitopes as they both reacted with an antibody to heparan sulphate proteoglycan from bovine glomerular basement membrane. 4. 4. On electron microscopy, both high and low charge density proteoglycans were visualized as ‘tadpole-like’ molecules, which showed a tendency to aggregate via their globular heads. 5. 5. Bovine aortic smooth muscle cells were cultured in the presence of [ 35 S]sulphate and [ 3 H]glucosamine. Proteoglycans were isolated from medium and cell layer extract by the methods outlined above. 6. 6. The major HSPG species isolated from medium were significantly larger than those from cell layer and displayed substantial heterogeneity in both size of HS chain after papain digestion and size of protein core after heparitinase digestion. 7. The major cell layer species yielded two HS species of widely differing mol. wt after papain digestion, and a very small protein core after heparitinase digestion. Therefore cell layer-associated HSPGs show a good deal more homogeneity than those found in the medium. 7. 8. Further ion-exchange chromatography after digestion with chondroitinase ABC revealed HSPG species of lower charge density, possibly derived from a hybrid chondroitin sulphate-dermatan sulphate proteoglycan (CS/DSPG) after removal of the CS/DS chains.

Solar domestic hot water systems have been installed at Camp Darby and the Leghorn Army Depot near Livorno, Italy, by the United States Army. These systems range from single panel installations providing hot water to maintenance shops to large multipanel systems serving barracks. Guidance provided in this bilingual (English-Italian) report includes operating and maintenance procedures and recommendations for spare parts inventory. Operating procedures address start-up, normal operations, shut-down, and response to abnormal conditions; maintenance procedures address collector fluid drainage and replacement and equipment change-out. Flow diagrams reflecting as-built conditions are also included for many of the systems. Water quality and corrosion control are also discussed.

The objectives of this secondary oil recovery project involving the Carter sandstone in northwest Alabama are: (1) To increase the ultimate economic recovery of oil from the Carter reservoirs, thereby increasing domestic reserves and lessening US dependence on foreign oil; (2) To extensively model, test, and monitor the reservoirs so their management is optimized; and (3) To assimilate and transfer the information and results gathered to other US oil companies to encourage them to attempt similar projects. Start-up water injection began on 0 1/12/93 at the Central Bluff Field, and daily operations began on 01/13/93. These operations include monitoring wellhead pressures at the injector and two producers, and injection water treatment. Water injection was running 200-300 bbl/day at the end of February. Once the unit is pressured-up well testing will be performed. Unitization was approved on 03/01/93.b. For the North Fairview Field correlations and log analyses were used to determine the fluid and rock properties. A summary of these properties is included in Table 1. The results of the log analysis were used to construct the hydrocarbon pore volume map shown on Figure 1. The map was planimetered to determine original oil-in-place (OOIP) values and the hydrocarbon pore volume bymore » tract. The OOIP summed over an tracts by this method is 824.7 Mbbl (Figure 2). Original oil-in-place was also calculated directly: two such independent calculations gave 829.4 Mbbl (Table 1) and 835.6 Mbbl (Table 2). Thus, the three estimates of OOIP are within one percent. The approximately 88% of OOIP remaining provides an attractive target for secondary recovery. Injection start-up is planned for mid-June.« less