bluuebunny/crossref_metadata_2025 huggingface dataset:
Extracellular Adenosine 5′-Triphosphate Modulates Insulin Secretion via Functionally Active Purinergic Receptors of X and Y Subtype
Authors: Santini Eleonora , Cuccato Sabina , Madec Stephanie , Chimenti Daniele , Ferrannini Ele , Solini Anna
Published: February 2009

Extracellular nucleotides modulate several cell functions via specific receptors, P2X and P2Y. We explored the differential role of these receptors in the control of insulin secretion (InSec). In INS-1e cells grown in 11 mm glucose and then acutely exposed to 3.3, 7.5, 11, or 20 mm, coincubation with ATP, the global agonist of both P2X and P2Y receptors, induced a dose-dependent (P < 0.0001) reduction in insulin release (P < 0.0001) that was more marked at higher glucose concentrations (P < 0.0001 for the interaction). This effect was fully prevented (P < 0.0001) by incubating ATP-treated cells in the presence of apyrase, an ecto-ATP/ADPase. Uridine 5′-triphosphate (UTP), preferential agonist of P2Y receptors, significantly stimulated InSec at all glucose concentrations tested, whereas benzoyl-benzoyl ATP (BzATP), a strong and highly selective P2X7 agonist, did not influence InSec. Oxidized ATP, which completely suppresses P2X activity, abolished the inhibitory effect of ATP on InSec. Similar results were obtained in MIN-6 cells. Stimulation with ATP, BzATP, and UTP dose-dependently increased Intracellular free Ca2+ concentrations. By small interfering RNA we show P2X3 and P2Y4 as the main responsible inhibitory and promoting effect on InSec, respectively. Because P2X7 is not directly involved in InSec, we tested whether the effect of ATP on hormone synthesis might be mediated by apoptosis. However, neither ATP nor BzATP induced either early or late apoptosis. We conclude that: 1) INS-1e cells express multiple purinergic receptors, 2) ATP reduces glucose-induced InSec as a net effect of inhibition through P2X and stimulation through P2Y receptors, and 3) P2X-mediated apoptosis is not involved in the inhibition of InSec.
Synthesis and Activity of Dafachronic Acid Ligands for the C. elegans DAF-12 Nuclear Hormone Receptor
Authors: Sharma Kamalesh K. , Wang Zhu , Motola Daniel L. , Cummins Carolyn L. , Mangelsdorf David J. , Auchus Richard J.
Published: February 2009

The nuclear hormone receptor DAF-12 from Caenorhabditis elegans is activated by dafachronic acids, which derive from sterols upon oxidation by DAF-9, a cytochrome P450. DAF-12 activation is a critical checkpoint in C. elegans for acquisition of reproductive competence and for entry into adulthood rather than dauer diapause. Previous studies implicated the (25S)-Δ7-dafachronic acid isomer as the most potent compound, but the (25S)-Δ4-isomer was also identified as an activator of DAF-12. To explore the tolerance of DAF-12 for structural variations in the ligand and to enable further studies requiring large amounts of ligands for DAF-12 and homologs in other nematodes, we synthesized (25R)- and (25S)-isomers of five dafachronic acids differing in A/B-ring configurations. Both the (25S)- and (25R)-Δ7-dafachronic acids are potent transcriptional activators in a Gal4-transactivation assay using HEK-293 cells, with EC50 values of 23 and 33 nm, respectively, as are (25S)- and (25R)-Δ4-dafachronic acids, with EC50 values of 23 and 66 nm, respectively. The (25S)- and (25R)-Δ5-isomers were much less potent, with EC50 values approaching 1000 nm, and saturated 5α- and 5β-dafachronic acids showed mostly intermediate potencies. Rescue assays using daf- 9-null mutants confirmed the results from transactivation experiments, but this in vivo assay accentuated the greater potencies of the (25S)-epimers, particularly for the (25S)-Δ7-isomer. We conclude that DAF-12 accommodates a large range of structural variation in ligand geometry, but (25S)-Δ7-dafachronic acid is the most potent and probably biologically relevant isomer. Potency derives more from the A/B-ring configuration than from the stereochemistry at C-25.
Blastocyst lineage formation, early embryonic asymmetries and axis patterning in the mouse
Authors: Rossant Janet , Tam Patrick P. L.
Published: February 2009

The investigation into lineage allocation and early asymmetries in the pre-and peri-implantation mouse embryo is gaining momentum. As we review here, new insights have been gained into the cellular and molecular events that lead to the establishment of the three lineages of the blastocyst, to the determination of the origin and the fates of the visceral endoderm in the peri-implantation mouse embryo, and to the generation of cellular and molecular activities that accompany the emergence of asymmetries in the pre-gastrulation embryo. We also discuss the continuing debate that surrounds the relative impacts of early lineage bias versus the stochastic allocation of cells with respect to the events that pattern the blastocyst and initiate its later asymmetries.
Evaluation of slamming loads using smoothed particle hydrodynamics and Reynolds-averaged Navier—Stokes methods
Authors: Viviani M , Brizzolara S , Savio L
Published: February 2009

A free surface Reynolds-averaged Navier—Stokes solver and a smoothed particle hydrodynamics method, the latter currently under development by the authors, have been applied to the evaluation of slamming loads (global forces and local pressures) over a series of two-dimensional cases for which experimental data (drop tests with a free falling rig) were available. In particular, numerical simulations were conducted on a wedge-shaped section with 30° deadrise and on a ship bow section; in both cases, different heel angles and different drop speeds have been considered, to analyse a wide range of cases and to assess not only the accuracy of the numerical methods in a single case, but also their capability to capture significantly different conditions. Results from both methods are presented and compared with available measurements, allowing an assessment of these different techniques to be made and their relative merits and shortcomings to be observed.
On the Integrated Production and Distribution Problem with Bidirectional Flows
Authors: Lei Lei , Zhong Hua , Chaovalitwongse W. Art
Published: February 2009

The integrated production and distribution problem with bidirectional flows is a complicated optimization problem, usually with large problem sizes when encountered in practice. In this study, we propose a partial linear programming relaxation-based heuristic approach to solve a variation of this problem. The approach is called a partial relaxation in the sense that it relaxes the integer requirements only on selected variables. We also report on the gaps between the optimal solution and the heuristic solution provided by this partial relaxation, including analytical gaps for a special case and empirical gaps for randomly generated test cases. Our study of this problem was motivated by the operational planning problem of a medical equipment leasing network that involves a forward flow for new and refurbished devices and a reverse flow for used devices to be returned to suppliers over a multiple time-period planning horizon.
Compliance with Osteoporosis Treatment Guidelines in Postmenopausal Women
Authors: Mountjoy Cary R , Shrader Sarah P , Ragucci Kelly R
Published: February 2009

Background:

Osteoporosis continues to be poorly managed despite compelling statistics indicating increased morbidity and mortality associated with fractures. Guideline compliance in individual practices must be evaluated to implement improvements in the care of patients with this disease state.

Objective:

To evaluate compliance with osteoporosis treatment guidelines by physicians and patients at 2 family medicine clinics affiliated with a large university teaching hospital.

Methods:

Postmenopausal women 65 years of age or older with the ICD-9 diagnosis code 733.0 for osteoporosis during the study period between July 2006 and July 2007 were identified through the family medicine electronic medical record (EMR). Of 133 patients, 113 were eligible for inclusion. A retrospective chart review was conducted and prospective voluntary telephone surveys were administered. The EMR of each eligible patient was examined for presence of a baseline dual-energy X-ray absorptiometry (DXA) scan as well as appropriate follow-up DXA monitoring, appropriateness of osteoporosis pharmacotherapy, calcium and vitamin D supplementation, and fracture history. The telephone survey was used to assess the patients' calcium use, nonpharmacologic recommendations received, and fracture incidence after diagnosis of osteoporosis.

Results:

Of 113 patients diagnosed with osteoporosis, 68 of 82 (82.9%) had appropriate baseline DXA scans; however, only 9 (13.2%) of these 68 patients had appropriate follow-up scans every 2 years thereafter. Sixty-five (57.5%) patients were on Food and Drug Administration–approved, guideline-endorsed pharmacotherapy for osteoporosis. Thirty-five (70%) of the 50 participants in the telephone survey reported taking calcium regularly, and 41 (82%) patients recalled receiving some nonpharmacologic advice. Thirteen (26%) patients reported a fracture after diagnosis.

Conclusions:

Osteoporosis care can be measurably improved at these clinics with use of baseline and appropriate follow-up DXA scans, increasing the number of patients who receive pharmacotherapy, and providing ongoing reinforcement of nonpharmacologic measures whereby bone health may be maintained.
Warfarin–Antiretroviral Interactions
Authors: Liedtke Michelle D , Rathbun R Chris
Published: February 2009

Objective:

To review the literature for information regarding interactions between warfarin and antiretroviral agents and evaluate the clinical significance of these interactions.

Data Sources:

Primary literature was identified through a search of MEDLINE (1950–July 2008) and International Pharmaceutical Abstracts (1970–July 2008) using individual antiretroviral drug names and the following key search terms: warfarin, antiretroviral, protease inhibitor, nonnucleoside reverse transcriptase inhibitor, cytochrome P450,2C9, HIV, and drug interactions. Relevant abstracts from infectious disease and HIV conferences (2005–2008), reference citations from relevant articles, and manufacturers' product information were also reviewed.

Study Selection and Data Extraction:

All English-language articles identified through the data search were examined. Studies and reports addressing warfarin interactions with antiretrovirals, CYP2C9 polymorphism, and antiretroviral CYP2C9 effects were evaluated. A total of 12 case reports were identified that described interactions between warfarin and either protease inhibitors (Pis) or nonnucleoside reverse transcriptase inhibitors (NNRTIs).

Data Synthesis:

The drugs used in the case reports were limited to 6 antiretroviral agents (efavirenz, nevirapine, lopinavir/ritonavir, nelfinavir, saquinavir, ritonavir). The mechanism of interaction between antiretroviral agents and warfarin appears to be mediated through alteration in CYP2C9 metabolism. Concurrent use of warfarin with efavirenz or saquinavir was associated with overanticoagulation, identified by increases in international normalized ratio (INR). Use of warfarin with lopinavir/ritonavir, nelfinavir, ritonavir, and nevirapine resulted in subtherapeutic INRs. Interactions with delavirdine, etravirine, and atazanavir are anticipated; however, no published cases have reported these interactions. Interactions between warfarin and nucleoside reverse transcriptase inhibitors, integrase inhibitors, fusion inhibitors, and CCR5 antagonists are not anticipated.

Conclusions:

Interactions between warfarin and antiretrovirals are likely, especially when Pls or NNRTIs are used. Induction or inhibition of warfarin metabolism may occur, depending on the specific antiretroviral agent. When warfarin is used concurrently with antiretrovirals, close monitoring of INR response is recommended in lieu of empiric warfarin dosing adjustments, given the limited information available and the quality of evidence.
Representing time‐varying cyclic dynamics using multiple‐subject state‐space models
Authors: Chow Sy‐Miin , Hamaker Ellen L. , Fujita Frank , Boker Steven M.
Published: February 2009

Over the last few decades, researchers have become increasingly aware of the need to consider intraindividual variability in the form of cyclic processes. In this paper, we review two contemporary cyclic state‐space models: Young and colleagues' dynamic harmonic regression model and Harvey and colleagues' stochastic cycle model. We further derive the analytic equivalence between the two models, discuss their unique strengths and propose multiple‐subject extensions. Using data from a study on human postural dynamics and a daily affect study, we demonstrate the use of these models to represent within‐person non‐stationarities in cyclic dynamics and interindividual differences therein. The use of diagnostic tools for evaluating model fit is also illustrated.
A model for the effects of job insecurity on performance, turnover intention, and absenteeism
Authors: Staufenbiel Thomas , König Cornelius J.
Published: February 2009

This study investigates the effects of job insecurity on four organizationally important outcomes: in‐role behaviour, organizational citizenship behaviour, turnover intention, and absenteeism. A model is tested in which job insecurity is simultaneously a hindrance and a challenge stressor. In particular, job insecurity is proposed to have a predominantly harmful effect on performance, turnover intention, and absenteeism, and it is argued that these effects are mediated by (reduced) work attitudes. In addition, job insecurity is also assumed to affect these behaviours in the opposite way (i.e. a suppressor effect) because job insecurity might motivate employees to make themselves more valuable to the organization by working harder and being less absent. The model is tested with a sample of 136 German non‐managerial employees. Data from supervisors (i.e. in‐role behaviour and organizational citizenship behaviour), the company's personnel files (i.e. absenteeism), and self‐reports (i.e. job insecurity, work attitudes, turnover intention, in‐role behaviour, and organizational citizenship behaviour) were used. Structural equation modelling showed that a model that included both negative and positive effects fitted the data best. The negative effect was stronger than the positive effect. The results show that the effects of job insecurity are more complex than previously assumed. In addition, the results also extend previous research into hindrance and challenge stressors because they show that stressors should not be categorized as either hindrance or challenge. Instead, it might be more appropriate to conceptualize hindrance and challenge as two dimensions.
Do fetal heart rate deceleration patterns during labor differ between various umbilical cord abnormalities?
Authors: Hasegawa Junichi , Matsuoka Ryu , Ichizuka Kiyotake , Nakamura Masamitsu , Sekizawa Akihiko , Okai Takashi
Published: February 2009

Objective: To examine differences in intrapartum fetal heart rate (FHR) patterns among cases with various cord abnormalities.

Methods: Vertex singleton cases with nuchal cord (226 cases), velamentous (12 cases), marginal cord insertion (53 cases) or hyper-coiled cord (39 cases) and without them (466) that were delivered at our hospital were examined. The relationship between cord abnormalities and intrapartum FHR patterns were retrospectively investigated. Deceleration patterns were analyzed for the presence of variable, early, late and prolonged decelerations. The frequencies of each FHR pattern per uterine contraction were assessed during 30 uterine contractions at the end of the first stage and throughout the entire second stage of labor.

Results: In the first stage of labor, frequencies of variable decelerations were 34.5±23.8% and 27.3±25.5% in cases with velamentous insertion and hyper-coiled cord, respectively. These were significantly higher than in controls (11.7±17.3%, P<0.0001). In the second stage of labor, however, frequencies of each deceleration were not different among various cord abnormalities.

Conclusion: Fetal heart rate tracing from the first stage of labor is indicated in cases with the prenatal diagnosis of velamentous insertion or hyper-coiling of the cord.
The effect of bilateral pelvic neurectomy on cervical ripening in pregnant rats
Authors: Mackay Lynette B. , Shi Leili , Maul Holger , Maner William L. , Garfield Robert E.
Published: February 2009

Aims: To determine the effect of bilateral pelvic neurectomy (BPN) on cervical ripening in pregnant rats by measuring cervical extensibility and changes in collagen cross-linkages.

Methods: Timed-pregnant rats were randomly laparotomized on days 9 or 10 of gestation and the pelvic nerves were exposed and either bilaterally transected, or left intact in sham control animals. The rats were sacrificed on day 18 and the uterine cervices obtained. Cervical ripening was assessed by cervical resistance-to-stretch, light-induced autofluorescence (LIF) of cross-linked collagen, and collagen changes analyzed by picrosirius polarization microscopy.

Results: Measurements of extensibility and collagen cross-linkages indicated that after BPN the cervix was significantly more ripened than the cervix from sham control animals.

Conclusion: BPN stimulates cervical ripening instead of inhibiting this event as previously proposed. Further studies in this area could be critical for developing treatments for dystocia, preterm labor, and cervical insufficiency.
The source of Helicobacter pylori infection in the neonatal period
Authors: Baldassarre Maria Elisabetta , Monno Rosa , Laforgia Nicola , Fumarola Luciana , Fanelli Margherita , Sgobba Cinzia , Hassan Cesare , Panella Carmine , Ierardi Enzo
Published: February 2009

Aims: To investigate the transmission of Helicobacter pylori in the perinatal period.

Methods: H. pylori status of 180 women was preliminarily screened by serology and stool antigen test (SAT) within the fourth day after delivery and a positive value was confirmed by 13C-urea breath test. Infants were analyzed by SAT at 1, 6, 12 and 18 months of age. H. pylori status was also investigated in the medical and paramedical staff of the Neonatology Unit.

Results: H. pylori infection was found in 34.4% of the women. At the 1st month of age, 5 out of 172 newborns (2.9%) were H. pylori positive by SAT. Three out of the five positive infants were born to H. pylori non-infected mothers. Formula feeding (P=0.02) and admission in intermediate-risk neonatal unit (P=0.01) were significantly related to a positive H. pylori result. Medical and paramedical staff of the neonatology unit was found H. pylori positive in 34.8% of cases. All five H. pylori positive children spontaneously cleared the infection.

Conclusions: Perinatal H. pylori SAT positive status is low in our area, and it may be found both in infants from infected or non-infected mothers. Formula feeding and admission in intermediate-risk neonatal unit appear to be related with H. pylori infection.
Standardization of Test Procedure for Tension Test on Coir Yarns and Woven Coir Geotextiles
Authors: Subaida E. A. , Chandrakaran S. , Sankar N.
Published: February 2009

This paper presents the results of an experimental investigation conducted to develop a standard test procedure for tension testing on coir yarns and woven coir geotextiles. Uniaxial tension tests were conducted on nine types of woven coir geotextiles and eleven types of coir yarns. Specimens of different dimensions were tested at various deformation rates. Test results indicated that tensile properties of coir yarns and geotextiles were largely influenced by testing parameters. Statistical analysis of yarn tension data was carried out to establish the gauge length, strain rate, and specimen dimensions of geotextiles. Consistent values of tensile strength and failure strain were obtained when gauge length and strain rate were adopted as 150 mm and 5 %/min, respectively. It was also observed that reliable results were obtained when the width of the geotextile specimen for tension test contained not less than ten yarns.
The Truth about Clams Casino
Authors: olver lynne m.
Published: February 2009

Julius Keller is generally credited for inventing Clams Casino at New York City's Narragensett Pier in 1917 for Mrs. Paran Stevens. A careful examination of primary sources does not confirm this claim. Our survey of historic American cookbooks and newspapers revealed strikingly similar dishes existing as early as 1883. Mr. Keller's connection with the Narragensett Pier and Mrs. Stevens are well documented. The Pier, however, was on the Rhode Island shore. Clams Casino is an excellent example of food lore. Dishes are not invented; they evolve.
Role of Compensatory Growth in Walleye Fingerling Production
Authors: Rosauer Daniel R , Morris Joseph E , Clayton Richard D
Published: February 2009

Compensatory growth during production of fingerling walleyes Sander vitreus was evaluated. Age-0 walleyes (mean weight ± SE = 26.1 ± 0.73 g) were stocked into nine 100-L tanks (three tanks/treatment). Fish were fed daily (control); fed for 5 d consecutively and then went unfed for 2 d (5-d treatment); or fed for 3 d consecutively and then went unfed for 4 d (3-d treatment). Treatments were repeated weekly for an 8-week period. Full compensation occurred in the 5-d treatment, as shown by increased specific growth rate (SGR) and no statistical difference in final weight relative to that of the control group. Fish in the 3-d treatment exhibited partial compensation in which SGR increased periodically, but final weight differed significantly from that of the control group. Information garnered from this study exemplifies the potential for achieving compensatory growth during fingerling walleye production.
Swimming Performance and Metabolism of Cultured Golden Shiners
Authors: Beecham Rachel V , Pearson Philip R , LaBarre Susan B , Minchew C Douglas
Published: February 2009

Swimming performance and metabolism of golden shiners Notemigonus crysoleucas were examined by use of swim tunnel respirometry. The oxygen consumption and tail beat frequency (TBF) at various swimming speeds, an estimation of the standard metabolic rate (SMR), and the critical swimming speed (U  crit) were determined for golden shiners that were tested in 10 groups of 5 individuals each. Oxygen consumption and TBF both increased as swimming speed increased. The mean U  crit for the first, second, and third individual to fatigue in each group was 38.0, 41.7, and 47.2 cm/s, respectively. The SMR was estimated at 131 mg O2·kg−1·h−1 for fish averaging 5.3 g. The active metabolic rate averaged 150 ± 14 mg O2·kg−1·h−1 (mean ± SE) at 10 cm/s, increased to 163 ± 20 mg O2·kg−1·h−1 at 30 cm/s, and peaked at 177 ± 19 mg O2·kg−1·h−1 at 50 cm/s. Total aerobic cost of transport (0.36 cal·g−1·km−1; i.e., the metabolic cost of swimming) and net cost of transport (0.08 cal·g−1·km−1) were lowest between 30 and 40 cm/s.
Production Methods for Food-Sized Bluegills
Authors: Hicks Charles E , Ellersieck Mark R , Borgwordt Cindy J
Published: February 2009

Growth of selected crosses (P1♀ × F1♂, F1♀ × P1♂, and F1♀ × F1♂) of Lincoln University bluegill stocks were evaluated. The purpose was to test the commercial potential for reaching marketable size (227–340 g) within 2 years in an indoor water-recycle system and grow-out in ponds. Pond hatched young-of-year bluegill were reared in a 12-tank (719 L/tank) indoor water-recycle system. Fish were fed to satiation three times daily. Fish were weighed and measured for total length (TL), for a 120-d growth trial. Initial mean fish weight and TL were 28.0 ± 15.8 g and 106 ± 16 mm, respectively. Final mean weight was 119.4 ± 54.9 g, and mean TL was 161 ± 19 mm. Crosses were significantly different (P ≤ 0.05). Initial female weight averaged 82.1 ± 32.5 g, and male weight averaged 158.6 ± 45.5 g. Feed conversion ratio was 1.26, and survival was 99.4%. Specific growth rate (SGR) averaged 1.21%/d with a mean length increase of 0.5 mm/d. Fish were then marked by specific crosses with colored visible implant elastromer tags. Fish were stocked in four 0.04-ha ponds (N = 600 fish/pond; density = 15,000 fish/ha) for 129 d. Final mean weight of fish in the pond study was 228.3 ± 71.7 g; mean TL was 200 ± 15 mm. Crosses were not significantly different from each other (P > 0.05). Sexual dimorphism was more pronounced after pond rearing; females averaged 175.4 ± 41.7 g and males averaged 284.0 ± 54.4 g. Results indicate bluegill grown in indoor recycle systems may reach target weights of 227–340 g within 2 years with the use of out-of-season spawning and selective breeding. Forty-eight percent reached or exceeded the minimum target weight (227–340 grams). This study also suggests that removing females could increase the number of fish reaching target weight by 33%.
Effect of Using Threadfin Shad as Forage for Channel Catfish Fed Daily or Every Third Day
Authors: Green Bartholomew , Perschbacher Peter , Ludwig Gerald
Published: February 2009

We evaluated whether stocking threadfin shad Dorosoma petenense as a forage fish in multiple-batch production ponds for channel catfish Ictalurus punctatus could substitute for formulated feed when channel catfish were fed daily or every 3 d. A completely randomized design in a 2 × 2 factorial arrangement was used for the experiment, which was conducted in twelve 0.1-ha earthen ponds. Prespawn adult threadfin shad were stocked at 404 kg/ha in six of the ponds, whereas the remaining ponds received no threadfin shad. Channel catfish stockers (0.35 kg/fish) were stocked at 5,040 kg/ha, and fingerlings (28.2 g/fish) were stocked at 14,820 fish/ha. Channel catfish were fed a floating feed (32% protein) to apparent satiation daily (D; 6 ponds) or every 3 d (3D; 6 ponds). After 144 d, mean channel catfish total net yield was unaffected by the presence of threadfin shad but was significantly greater for fish in the D treatment (7,256 kg/ha) than for fish in the 3D treatment (2,431 kg/ha). Mean fish weight at harvest also was greater in the D treatment than in the 3D treatment. The amount of feed administered in the 3D treatment was 62% of that used in the D treatment, thus reducing net total yield by 66% and slowing growth in fish from the 3D treatment. Nearly 90% of stockers in the 3D treatment failed to reach market size (0.68 kg/fish) and would have required a third season to reach harvest weight. At the rate used in this experiment, stocking of threadfin shad as forage fish into channel catfish production ponds did not appear to be a viable method of substituting for formulated feed during the growing season.
Effect of Temperature on Growth, Feed Utilization, and Immune Status of Channel Catfish in a Recirculating System
Authors: Suja Baby , Phillips Harold , Lochmann Rebecca , Chen Ruguang
Published: February 2009

A feeding trial was conducted to determine growth, survival, feed utilization, nonspecific immune response, and proximate and fatty acid composition of the fillet of stocker-sized channel catfish Ictalurus punctatus reared at temperatures considered slightly below optimal (22°C), optimal (27°C), or slightly above optimal (32°C) for feed intake and growth of this species. Groups of 100 stockers initially averaging 111.4 ± 1.7 g (mean ± SE) were stocked into each of four 1,140-L tanks within each of three independent recirculating systems and were fed a 32% protein commercial floating pellet once daily to satiation for 14 weeks. Feed intake was calculated weekly. Subsamples of fish were weighed every 3 weeks to track growth. At the end of the trial, all fish were counted and weighed. Five fish per tank were bled to analyze hematology and immunological parameters. Analysis of variance and Fisher's least-significant-difference tests were used to compare differences among treatment means (P ≤ 0.05). Weight gain (252.2 ± 20.0 g) was highest and feed conversion ratio (1.3 ± 0.0) was lowest in fish held at 27°C, while survival (99 ± 0.4%) was highest in fish held at 32°C. Feed intake did not differ by temperature. When differences in final body weight were considered, the protein, dry matter, and ash in the fillet did not differ by temperature. Both temperature and final body weight affected fillet lipid. Fish reared at 32°C were smaller but had more fillet lipid than fish reared at 27°C. Hepatosomatic index did not differ by temperature. Monounsaturates in muscle lipid declined with temperature, while total n-6 highly unsaturated fatty acids and the index of fatty acid unsaturation were higher in fish held at 22°C than in those held at 32°C. Alternative complement activity was highest in fish held at 22°C, while lysozyme activity was highest at 32°C. Temperature had numerous effects on fish performance when diet was fixed. These effects must be considered when diet composition is manipulated to enhance channel catfish performance at different temperatures.
Effects of Loading Density on Golden Shiner Survival during and after Hauling
Authors: Pearson Philip R , Small Brian C , Beecham Rachel Venn , Sink Todd D , LaBarre Susan B , Minchew C Douglas
Published: February 2009

Four hauling trips of approximately 6 h each were conducted to investigate effects of loading density on survival of golden shiners Notemigonus crysoleucas. Commercially graded golden shiners (mean weight ± SE, 3.3 ± 0.04 g) were transported at densities of 120, 180, and 240 g of fish/L of water in insulated hauling tanks that were filled with fresh well water, chilled with unchlorinated block ice, and aerated with pure oxygen. The criterion for determining success or failure was golden shiner survival. Transportation at a given density was deemed successful if survival both at trip's end and at 18 h postdelivery was at least 99%. At all three hauling densities evaluated, survival exceeded 99% both at trip's end and at 18 h postdelivery. Furthermore, increasing loading density had no effect on whole-body cortisol concentrations, demonstrating that no significant stress response occurred. Un-ionized ammonia concentration increased with loading density (range, 0.05–0.46 mg/L) but had no effect on fish survival. Results of this study indicate that golden shiners can be successfully (≥99% survival) transported for up to 6 h at a density of 240 g/L in well water chilled with unchlorinated block ice and aerated with pure oxygen. Higher loading densities could mitigate the effect of escalating transport cost for commercial farmers.
Concrete grandstands. Part II: numerical modelling
Authors: Karadelis J. N.
Published: February 2009

This paper outlines the essential theoretical basis upon which a rigorous finite-element model comprising material non-linearities and failure criteria for both, concrete and steel reinforcement, is built. A numerical algorithm describing the analysis process, based on recent advances in numerical methods of reinforced concrete and a finite-element code were developed in parallel and summarised in a concise flowchart. It was concluded that the finite-element model captured successfully the non-linear flexural behaviour of the terrace units to failure, the formation of a ‘bowl’ at the centre, the lifting of the free tread ends and the rotation about a longitudinal axis. The results produced were rather sensitive to the modulus of elasticity assigned to concrete as well as the initial and, to a lesser extend, additional tangent moduli assigned to the reinforcement. The model was capable of predicting the introduction and propagation of flexural cracks formed around the midspan. More rigorous analytical and numerical work is under way, depicting both static and dynamic conditions, in an effort to establish suitable FE benchmarks, hence reducing uncertainties and increasing confidence of the performance of these structures during their working life.
Testing and applying a fish vitellogenesis model to evaluate laboratory and field biomarkers of endocrine disruption in Atlantic croaker (Micropogonias undulatus) exposed to hypoxia
Authors: Murphy Cheryl A. , Rose Kenneth A. , Rahman M. Saydur , Thomas Peter
Published: February 2009

Recently, hypoxia has been shown to act as an endocrine disruptor. We used a model of vitellogenesis in a female sciaenid fish to simulate the effects of hypoxia and to determine if reproductive impairment observed in field-caught fish could be attributed to dissolved oxygen conditions at the sampling sites. The model is a set of coupled, ordinary differential equations that simulate major biochemical reactions from the secretion of gonadotropin to production of vitellogenin. Various intermediate variables in the model correspond to commonly measured biomarkers, and we assume a direct relationship between cumulative vitellogenin (VTG) and the gonadosomatic index (GSI). Model predictions were compared to results of laboratory studies that examined the effects of hypoxia on Atlantic croaker (Micropogonias undulatus) reproduction. When hypoxia was assumed to cause reduced gonadotropin and impaired aromatase activity, model predictions of VTG production were similar to laboratory-measured reductions in GSI. The model was then applied to reproductive biomarkers measured in fish from normoxic and hypoxic locations in Pensacola Bay (FL, USA). We simulated the relationship between reduced estradiol-17β and VTG production under hypoxia, and we compared these results with field data. Good agreement between field and simulation results suggested that croaker collected from hypoxic sites in October were exposed to hypoxic conditions for an extended period during gonadal recrudescence and that hypoxia was a dominant cause for the reduced GSIs. Monte Carlo uncertainty analyses suggested that the maximum rate of free testosterone production is the most sensitive parameter. Our simulations demonstrated that the model can be used identifying the mechanism underlying endocrine disruption and for interpreting field-measured biomarkers in situations of multiple stressors.
Life-Course Socioeconomic Position and Incidence of Diabetes Mellitus Among Blacks and Whites: The Alameda County Study, 1965–1999
Authors: Maty Siobhan C. , James Sherman A. , Kaplan George A.
Published: February 2009

Objectives. We examined associations between several life-course socioeconomic position (SEP) measures (childhood SEP, education, income, occupation) and diabetes incidence from 1965 to 1999 in a sample of 5422 diabetes-free Black and White participants in the Alameda County Study.

Methods. Race-specific Cox proportional hazard models estimated diabetes risk associated with each SEP measure. Demographic confounders (age, gender, marital status) and potential pathway components (physical inactivity, body composition, smoking, alcohol consumption, hypertension, depression, access to health care) were included as covariates.

Results. Diabetes incidence was twice as high for Blacks as for Whites. Diabetes risk factors independently increased risk, but effect sizes were greater among Whites. Low childhood SEP elevated risk for both racial groups. Protective effects were suggested for low education and blue-collar occupation among Blacks, but these factors increased risk for Whites. Income was protective for Whites but not Blacks. Covariate adjustment had negligible effects on associations between each SEP measure and diabetes incidence for both racial groups.

Conclusions. These findings suggest an important role for life-course SEP measures in determining risk of diabetes, regardless of race and after adjustment for factors that may confound or mediate these associations.
Core Competencies for Injury and Violence Prevention
Authors: Songer Thomas , Stephens-Stidham Shelli , Peek-Asa Corinne , Bou-Saada Ingrid , Hunter Wanda , Lindemer Kristen , Runyan Carol
Published: February 2009

Efforts to reduce the burden of injury and violence require a workforce that is knowledgeable and skilled in prevention. However, there has been no systematic process to ensure that professionals possess the necessary competencies.

To address this deficiency, we developed a set of core competencies for public health practitioners in injury and violence prevention programs. The core competencies address domains including public health significance, data, the design and implementation of prevention activities, evaluation, program management, communication, stimulating change, and continuing education. Specific learning objectives establish goals for training in each domain.

The competencies assist in efforts to reduce the burden of injury and violence and can provide benchmarks against which to assess progress in professional capacity for injury and violence prevention.
Surveillance of Antituberculosis Drug Resistance Among Children From the Western Cape Province of South Africa—An Upward Trend
Authors: Schaaf H. Simon , Marais Ben J. , Hesseling Anneke C. , Brittle Wendy , Donald Peter R.
Published: February 2009

Objectives. We assessed the prevalence of antituberculosis drug resistance among children with tuberculosis (TB) in the Western Cape Province of South Africa.

Methods. Drug susceptibility testing for isoniazid and rifampin was prospectively done on all children with culture-confirmed TB at Tygerberg Children's Hospital, Cape Town, from March 2005 through February 2007. Survey results were compared with results from 2 previous surveys.

Results. We found 291 children had culture-confirmed TB. Resistance to isoniazid or rifampin increased from 21 of 306 (6.9%) to 41 of 319 (12.9%) and 43 of 285 (15.1%) in the first to third surveys (P = .005) and multidrug resistance from 7 of 306 (2.3%) to 18 of 319 (5.6%) and 19 of 285 (6.7%; P = .033). Although previously treated children had significantly more drug resistance than did new TB cases (19 of 66 [28.8%] vs 24 of 225 [10.7%]; odds ratio = 3.39; 95% confidence interval = 1.62, 7.05), evidence suggests transmission rather than acquisition of resistance. HIV infection was not significantly associated with drug resistance.

Conclusions. Results indicate a high and rising prevalence of anti-TB drug resistance among children in the Western Cape, which suggests ongoing transmission of drug-resistant strains within the community. Improved control of TB in adults, including early identification and treatment of drug-resistant cases, is necessary to reduce transmission to children.
Evaluation of Phosphorus Source Coefficients as Predictors of Runoff Phosphorus Concentrations
Authors: Smith Matt C. , White John W. , Coale Frank J.
Published: February 2009

Many states have adopted a P site index (PSI) as a risk assessment tool to determine when P‐based nutrient management is required for a given agricultural field. Some PSIs use a weighting factor, the phosphorus source coefficient (PSC), to account for differences in P solubility between organic P sources. Information relating to appropriate values of PSC for various organic P sources is limited. The objectives of this study were to determine PSCs for organic P sources and to examine the relationship between PSCs and P concentrations measured in simulated rainfall runoff. An incubation study was used to calculate PSCs based on the extractability of P from organic P sources (separated and unseparated liquid dairy manure, digested dairy manure, dairy manure solids, poultry litter, and compost) relative to P from triple superphosphate fertilizer. The PSCs from the 14‐d incubations were the best predictors of runoff P after 14 d soil equilibration in the runoff boxes. The values for iron‐oxide strip phosphorus (FeO‐P) PSC ranged from 78% for compost to 28% for poultry litter and were significantly related to runoff DR‐P (r2 = 0.80***) and FeO‐P (r2 = 0.76***) during the 14‐d runoff event. Mehlich 3 PSCs ranged from 59% for compost to 30% for unseparated dairy manure and were better predictors of DR‐P and FeO‐P during the 56‐d event (r2 = 0.73*** and 0.65***, respectively). The results of this study indicate that PSCs based on soil incubations may improve the ability of PSCs to predict the risk of runoff transport, particularly after manure incorporation.
Brassica Cover Crops for Nitrogen Retention in the Mid‐Atlantic Coastal Plain
Authors: Dean Jill E. , Weil Ray R.
Published: February 2009

Brassica cover crops are new to the mid‐Atlantic region, and limited information is available on their N uptake capabilities for effective N conservation. Forage radish (Raphanus sativus L. cv. Daikon), oilseed radish (Raphanus sativus L. cv. Adagio), and rape (Brassica napus L. cv. Dwarf Essex) were compared with rye (Secale cereale L. cv. Wheeler), a popular cover crop in the region, with regard to N uptake ability and potential to decrease N leaching at two sites in Maryland. Plants were harvested in fall and spring for dry matter and N analysis. Soil samples from 0 cm to 105 to 180 cm depth were obtained in fall and spring for NH4–N and NO3–N analyses. Ceramic cup tension lysimeters were installed at depths of 75 to 120 cm to monitor NO3–N in soil pore water. Averaged across 3 site‐years, forage radish and rape shoots had greater dry matter production and captured more N in fall than rye shoots. Compared with a weedy fallow control, rape and rye caused similar decreases in soil NO3–N in fall and spring throughout the sampled profile. Cover crops had no effect on soil NH4–N. During the spring on coarse textured soil, pore water NO3–N concentrations in freeze‐killed Brassica (radish) plots were greater than in control and overwintering Brassica (rape) and rye plots. On fine textured soil, all cover crops provided a similar decrease in pore water NO3–N concentration compared with control. On coarse textured soils, freeze‐killed Brassica cover crops should be followed by an early‐planted spring main crop.
Resuspension‐Mediated Temporal Variation in Phosphorus Concentrations and Internal Loading
Authors: Niemistö Juha P. , Holmroos Heidi , Nurminen Leena , Horppila Jukka
Published: February 2009

Sediment resuspension is an important factor for nutrient cycling in shallow lakes. Temporal variation in sediment resuspension and its influence on P concentrations and internal loading were studied in the shallow and eutrophic Kirkkojärvi basin. Gross sedimentation and sediment resuspension were estimated with sediment traps during three exposure periods in spring, midsummer, and autumn. The effects of resuspension on the concentrations of suspended solids, total phosphorus (TP), soluble reactive P, and chlorophyll a were followed. The level of sediment resuspension was greatest in midsummer (July–August 63.9 g dw m−2 d−1), due to strong phytoplankton blooms modifying the surface film of the sediment more prone to resuspension. The dependence of high total P concentrations (226–385 μg L−1) on sediment resuspension and suspended solids was significant at the time. The concentrations of soluble reactive P were also high in midsummer (52–91 μg L−1), but had a negative dependence on suspended solids. This dependence was due to algal assimilation as was proved by a negative effect of chlorophyll a on soluble reactive P. Consequently, we suggest that the increase in the total P concentrations caused by sediment resuspension in midsummer was possibly intensified by strong algal blooms occurring at the time because strong assimilation resulting in high pH (pH 7.3 in May, 9.3–10.2 in July–August, 7.6 in October) may have increased the desorption of P from the suspended inorganic particles and intensified the P transfer into the phytoplankton biomass in midsummer.
A Biosecure Composting System for Disposal of Cattle Carcasses and Manure Following Infectious Disease Outbreak
Authors: Xu Weiping , Reuter Tim , Inglis G. Douglas , Larney Francis J. , Alexander Trevor W. , Guan Jiewen , Stanford Kim , Xu Yongping , McAllister Tim A.
Published: February 2009

During outbreaks of infectious animal diseases, composting may be an effective method of disposing of mortalities and potentially contaminated manure. Duplicate biosecure structures containing 16 cattle (Bos taurus) mortalities (343 kg average weight) were constructed with carcasses placed on a 40‐cm straw layer and overlaid with 160 cm of feedlot manure. At a depth of 80 cm (P80), compost heated rapidly, exceeding 55°C after 8 d and maintained temperatures of 55 to 65°C for > 35 d. Temperatures at 160 cm (P160) failed to exceed 55°C, but remained above 40°C for >4 mo. To investigate rates of microbial inactivation, Escherichia coli O157:H7, Campylobacter jejuni, and Newcastle disease virus (NDV) were inoculated in manure (E. coli O157:H7 and C. jejuni ≈ 108 CFU g−1; NDV, ≈ 106 EID50 g−1), embedded at P80 and P160 and retrieved at intervals during composting. Escherichia coli O157:H7 and NDV were undetectable after 7 d at both depths. The C. jejuni DNA was detected up to 84 d at P80 and >147 d at P160. To estimate degradation of recalcitrant substrates, bovine brain, hoof, and rib bones were also embedded at P80 and P160 and retrieved at intervals. Residues of soft tissues remained in carcasses after opening at 147 d and bovine tissue decomposition ranked as brain > hoof > bone. More than 90% dry matter (DM) of brain disappeared after 7 d and 80% DM of hoof decomposed after 56 d. High degradation of cattle carcasses, rapid suppression of E. coli O157:H7 and NDV and reduction in viable cell densities of >6 logs for C. jejuni demonstrates that the biosecure composting system can dispose of cattle carcasses and manure in an infectious disease outbreak.
Characterizing Potential Water Quality Impacts from Soils Treated with Dust Suppressants
Authors: Beighley R. Edward , He Yiping , Valdes Julio R.
Published: February 2009

Two separate laboratory experiment series, surface runoff and steady‐state seepage, were performed to determine if dust suppressant products can be applied to soils with an expected minimal to no negative impact on water quality. The experiments were designed to mimic arid field conditions and used two soils (clayey and sandy) and six different dust suppressants. The two experiments consisted of: (i) simulated rainfall (intensities of 18, 33, or 61 mm h−1) and associated runoff from soil trays at a surface slope of 33%; and (ii) steady‐state, constant head seepage through soil columns. Both experiment series involved two product application scenarios and three application ages (i.e., to account for degradation effects) for a total of 126 surface runoff and 80 column experiments. One composite effluent sample was collected from each experiment and analyzed for pH, electrical conductivity, total suspended solids (TSS), total dissolved solids, dissolved oxygen, total organic carbon, nitrate, nitrite, and phosphate. Paired t tests at 1 and 5% levels of significance and project specific data quality objectives are used to compare water quality parameters from treated and untreated soils. Overall, the results from this laboratory scale study suggest that the studied dust suppressants have minimal potential for adverse impacts to selected water quality parameters. The primary impacts were increased TSS for two synthetic products from the surface runoff experiments on both soils. The increase in TSS was not expected based on previous studies and may be attributed to this study's focus on simulating real‐world soil agitation/movement at an active construction site subjected to rough grading.