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Potential new sources of phosphorus (P) fertilizer are the recovered P from livestock wastewater through chemical precipitation and the ash from combusting animal manures. Although most of the research on P losses from conservation tillage include high water-soluble P compounds from commercial fertilizer sources, information on the use of non-conventional, low water-soluble, recycled P sources is scarce. Particularly for sandy soils of the United States (US) Southeastern Coastal Plain region, research driven information on P loss into the environment is needed to determine recommendations for a direct use of new recycled P sources as crop P fertilizers. The objective of this study is to investigate the potential P runoff from sandy soils under conservation tillage, fertilized with recovered P from liquid swine manure and turkey litter ash in comparison with commercial P fertilizer triple superphosphate (TSP). The field study included two typical sandy soils of the US Southeastern Coastal Plain region, the Noboco and Norfolk. Simulated rain corresponding to the annual 30-min rainfall in the study site (Florence County, South Carolina) was applied to plots treated with recovered P from liquid swine manure, turkey litter ash, and TSP, including a control with no P added. The runoff was monitored and sampled every 5 min during the test and composite soil samples were collected from the top (0-15 cm) and subsurface (15-30 cm) soil layers in each plot. Laboratory analyses were conducted to quantify both total P (TP) and soluble reactive P (SRP) in runoff samples, and the soil test P in the soil layers. Two-way analyses of variances show significant treatment effects on both TP and SRP runoff. The quantities of SRP runoff from plots treated with the recovered P from swine manure and turkey litter ash represent respectively 1% and 7-8% of SRP runoff from plots treated with TSP. Hence, the use of the recovered P materials as crop P fertilizers through surface broadcast application present less environmental risks compared to commercial TSP., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Ltd.)

Objectives: Rates of postpartum smoking relapse are high (70-90%) but standard relapse prevention interventions are not effective postpartum. This pilot study evaluated effects of a combined relapse prevention and sleep intervention on sleep and relapse to smoking., Methods: Twenty-eight postpartum mothers were assigned to the intervention group-combined relapse prevention and behavioral sleep intervention-or to the comparison group-relapse prevention alone. Questionnaires and actigraphy were completed at baseline (1-week postpartum), post-treatment (8-weeks postpartum), and follow-up (12-weeks postpartum). Sleep diaries were completed weekly for the first 8 weeks postpartum and once at 12 weeks postpartum. To corroborate abstinence, CO levels in expired air were measured weekly for the first 8 weeks postpartum and at follow-up. Timeline Followback (TLFB) and salivary cotinine analysis were conducted at baseline, post-treatment, and follow-up to assess for nicotine and other substance use (TLFB) and to further corroborate abstinence (salivary cotinine analysis)., Results: The sleep intervention lengthened maternal nighttime actigraphic sleep by an average of 48 minutes nightly; lengthened the longest bout of consolidated actigraphic sleep by an average of 42 minutes nightly; increased actigraphic sleep efficiency into the healthy range (> 85%); and lowered subjective ratings of sleep disturbance (ps < .05). Findings were inconclusive regarding whether better sleep was associated with abstinence. Post Hoc analyses identified the presence of an additional support person in the home as well as social and emotional support as being positively correlated with smoking abstinence (p < .05; p < .01)., Conclusions for Practice: (1) Postpartum sleep can be improved with behavioral interventions in women with a history of smoking. (2) Social-emotional postpartum support is an important factor in preventing smoking relapse for these women., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The Oronogo-Duenweg mining belt is a designated United States Environmental Protection Agency Superfund site due to lead-contaminated soil and groundwater by former mining and smelting operations. Sites that have undergone remediation - in which the O, A, and B horizons have been removed alongside the lead contamination - have an exposed C horizon and are incalcitrant to revegetation efforts. Soils also continue to contain quantifiable Cd and Zn concentrations. In order to improve soil conditions and encourage successful site revegetation, our study employed three biochars, sourced from different feedstocks (poultry litter, beef lot manure, and lodge pole pine), at two rates of application (2.5%, and 5%), coupled with compost (0%, 2.5% and 5% application rates). Two plant species - switchgrass ( Panicum virgatum ) and buffalograss ( Bouteloua dactyloides ) - were grown in the amended soils. Amendment of soils with poultry litter biochar applied at 5% resulted in the greatest reduction of soil bioavailable Cd and Zn. Above ground biomass yields were greatest with beef lot manure biochar applied at 2.5% with 5% compost, or with 5% biochar at 2.5% and 5% compost rates. Maximal microbial biomass was achieved with 5% poultry litter biochar and 5% compost, and microbial communities in soils amended with poultry litter biochar distinctly clustered away from all other soil treatments. Additionally, poultry litter biochar amended soils had the highest enzyme activity rates for β-glucosidase, N-acetyl-β-D-glucosaminidase, and esterase. These results suggest that soil reclamation using biochar and compost can improve mine-impacted soil biogeophysical characteristics, and potentially improve future remediation efforts.

This study examined the course of antidepressant use, sleep quality, and depression severity from pregnancy through 6-month postpartum in women with and without a depressive disorder during pregnancy. Women (N = 215) were interviewed during pregnancy, 1- and 6-month postpartum. Mixed linear models were used to examine the longitudinal course and inter-relationships for the time-varying variables of antidepressant use, subjective sleep quality, and depression severity. Pregnant women with a depressive disorder who did not use antidepressants had more variable depression severity over time with improvements in depression severity by 6-month postpartum. In contrast, the depression severity of their medicated counterparts remained stable and high throughout. Pregnant women without a depressive disorder had worse sleep quality when using antidepressants compared with when they were not. Antidepressant use significantly strengthened the magnitude of the effect of sleep quality on depression severity in women with a depressive disorder during pregnancy. When prenatally depressed women use antidepressants, their sleep disturbance is more highly linked to depression severity than when they do not. Furthermore, antidepressants are not adequately treating the sleep disturbance of these women or their remitted counterparts, leaving both groups vulnerable to significant negative mental and physical health outcomes.

Objective: To evaluate associations between actigraphic sleep patterns, subjective sleep quality, and daytime functioning (ie, sleepiness, symptoms of depression, and delinquency and other conduct problems) in at-risk adolescents., Design: Prospective, observational cohort study., Setting: Providence, RI, predominantly home and school and 2 visits to the Brown Center for the Study of Children at Risk., Participants: A diverse group of low-income 13-year-olds (n = 49) with and without prenatal drug exposure., Interventions: None., Measurements: Actigraphy, sleep diaries, and sleep and health questionnaires., Results: Above and beyond the effects of prenatal drug exposure and postnatal adversity, actigraphic daytime sleep was a significant predictor of daytime sleepiness and delinquency. Subjective sleep quality was a significant predictor of daytime sleepiness, delinquency, and depressive symptoms. Later bed times predicted increased delinquency., Conclusions: There was a unique effect of actigraphic daytime sleep duration, subjective nighttime sleep quality, and bedtime on daytime functioning (ie, sleepiness, symptoms of depression, and delinquency and other conduct problems) of at-risk adolescents. In these vulnerable youth, these problematic sleep patterns may contribute to feeling and behaving poorly. Intervention studies with at-risk teens should be conducted to further explore the role of these sleep parameters on daytime functioning., (Copyright © 2015 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.)

Unlabelled: Recently, the U.S. Environmental Protection Agency (EPA) posted a ground-based optical remote sensing method on its Web site called Other Test Method (OTM) 10 for measuring fugitive gas emission flux from area sources such as closed landfills. The OTM 10 utilizes the vertical radial plume mapping (VRPM) technique to calculate fugitive gas emission mass rates based on measured wind speed profiles and path-integrated gas concentrations (PICs). This study evaluates the accuracy of the VRPM technique in measuring gas emission from animal waste treatment lagoons. A field trial was designed to evaluate the accuracy of the VRPM technique. Control releases of methane (CH4) were made from a 45 m×45 m floating perforated pipe network located on an irrigation pond that resembled typical treatment lagoon environments. The accuracy of the VRPM technique was expressed by the ratio of the calculated emission rates (QVRPM) to actual emission rates (Q). Under an ideal condition of having mean wind directions mostly normal to a downwind vertical plane, the average VRPM accuracy was 0.77±0.32. However, when mean wind direction was mostly not normal to the downwind vertical plane, the emission plume was not adequately captured resulting in lower accuracies. The accuracies of these nonideal wind conditions could be significantly improved if we relaxed the VRPM wind direction criteria and combined the emission rates determined from two adjacent downwind vertical planes surrounding the lagoon. With this modification, the VRPM accuracy improved to 0.97±0.44, whereas the number of valid data sets also increased from 113 to 186., Implications: The need for developing accurate and feasible measuring techniques for fugitive gas emission from animal waste lagoons is vital for livestock gas inventories and implementation of mitigation strategies. This field lagoon gas emission study demonstrated that the EPA's vertical radial plume mapping (VRPM) technique can be used to accurately measure lagoon gas emission with two downwind vertical concentration planes surrounding the lagoon.

This study evaluated the impact of gas concentration and wind sensor locations on the accuracy of measuring gas emission rates from a lagoon environment using the backward Lagrangian stochastic (bLS) inverse-dispersion technique. Path-integrated concentrations (PICs) and three-dimensional (3D) wind vector data were collected at different locations within the lagoon landscape. A floating 45 m × 45 m perforated pipe network on an irrigation pond was used as a synthetic distributed emission source for the controlled release of methane. A total of 961 15-min datasets were collected under different atmospheric stability conditions over a 2-yr period. The PIC location had a significant impact on the accuracy of the bLS technique. The location of the 3D sonic anemometer was generally not a factor for the measured accuracies with the PIC positioned on the downwind berm. The PICs across the middle of the pond consistently produced the lowest accuracy with any of the 3D anemometer locations (<69% accuracy). The PICs located on the downwind berm consistently yielded the best bLS accuracy regardless of whether the 3D sonic anemometer was located on the upwind, side, or downwind berm (accuracies ranged from 79 to 108%). The accuracies of the emission measurements with the berm PIC-berm 3D setting were statistically similar to that found in a more ideal homogeneous grass field. Considering the practical difficulties of setting up equipment and the accuracies associated with various sensor locations, we recommend that wind and concentration sensors be located on the downwind berm., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

There are few options for prophylaxis after exposure to Bacillus anthracis, especially in children and women of childbearing potential. Faropenem is a beta-lactam in the penem subclass that is being developed as an oral prodrug, faropenem medoxomil, for the treatment of respiratory tract infections. Faropenem was shown to have in vitro activity against B. anthracis strains that variably express the bla1 beta-lactamase (MIC range,

Biofuels are a major topic of global interest and technology development. Whereas bioenergy crop production is highly dependent on water, bioenergy development requires effective allocation and management of water. The objectives of this investigation were to assess the bioenergy production relative to the impacts on water resource related factors: (1) climate and weather impact on water supplies for biomass production; (2) water use for major bioenergy crop production; and (3) potential alternatives to improve water supplies for bioenergy. Shifts to alternative bioenergy crops with greater water demand may produce unintended consequences for both water resources and energy feedstocks. Sugarcane and corn require 458 and 2036 m(3) water/m(3) ethanol produced, respectively. The water requirements for corn grain production to meet the US-DOE Billion-Ton Vision may increase approximately 6-fold from 8.6 to 50.1 km(3). Furthermore, climate change is impacting water resources throughout the world. In the western US, runoff from snowmelt is occurring earlier altering the timing of water availability. Weather extremes, both drought and flooding, have occurred more frequently over the last 30 years than the previous 100 years. All of these weather events impact bioenergy crop production. These events may be partially mitigated by alternative water management systems that offer potential for more effective water use and conservation. A few potential alternatives include controlled drainage and new next-generation livestock waste treatment systems. Controlled drainage can increase water available to plants and simultaneously improve water quality. New livestock waste treatments systems offer the potential to utilize treated wastewater to produce bioenergy crops. New technologies for cellulosic biomass conversion via thermochemical conversion offer the potential for using more diverse feedstocks with dramatically reduced water requirements. The development of bioenergy feedstocks in the US and throughout the world should carefully consider water resource limitations and their critical connections to ecosystem integrity and sustainability of human food., (Published by Elsevier Ltd.)

Coastal bermudagrass (Cynodon dactylon L.) may be a potentially important source of bio-based energy in the southern US due to its vast acreage. It is often produced as part of a waste management plan with varying nutrient composition and energy characteristics on fields irrigated with livestock wastewater. The objective of this study was to determine the effect of subsurface drip irrigation with treated swine wastewater on both the quantity and quality of bermudagrass bioenergy. The treated wastewater was recycled from an advanced treatment system and used for irrigation of bermudagrass in two crop seasons. The experiment had nine water and drip line spacing treatments arrayed in a randomized complete block-design with four replicates. The bermudagrass was analyzed for calorific and mineral contents. Bermudagrass energy yields for 2004 and 2005 ranged from 127.4 to 251.4MJ ha(-1). Compared to irrigation with commercial nitrogen fertilizer, the least biomass energy density was associated with bermudagrass receiving treated swine wastewater. Yet, in 2004 the wastewater irrigated bermudagrass had greater hay yields leading to greater energy yield per ha. This decrease in energy density of wastewater irrigated bermudagrass was associated with increased concentrations of K, Ca, and Na. After thermal conversion, these compounds are known to remain in the ash portion thereby decreasing the energy density. Nonetheless, the loss of energy density using treated effluent via SDI may be offset by the positive influence of these three elements for their catalytic properties in downstream thermal conversion processes such as promoting a lesser char yield and greater combustible gas formation.

Waste handling systems for confined swine production in the upper South (approximately 32-37 degrees N and 79-93 degrees W) depend mainly on anaerobic lagoons and application of the waste effluent to cropland. The main objective of this study was to evaluate the quality of 'Coastal' bermudagrass [Cynodon dactylon (L.) Pers.] hay receiving effluent generated from a raw swine waste treatment system designed to reduce P and K concentrations and delivered by subsurface drip irrigation (SDI) compared with hay produced from commercial N fertilizer. Eight treatments, consisting of commercial N fertilizer or effluent, each irrigated at two irrigation rates (75 and 100% of estimated evapotranspiration) and two lateral spacings (0.6 and 1.2 m), were compared with a control treatment of commercial N fertilizer without irrigation. Three harvests were taken in each of 2 yr and five of the six evaluated using wether sheep (30-45 kg). Greatest dry matter intake (DMI) per unit body weight occurred for the control vs. all irrigated treatments (1.94 vs. 1.77 kg 100(-1) kg; P = 0.02; SEM = 0.11). Among irrigated treatments, DMI was greatest from commercial N vs. effluent (1.81 vs. 1.71 kg 100(-1) kg; P = 0.05; SEM = 0.11). Dry matter intake was similar for the 75% rate treatments and the non-irrigated treatment (mean, 1.87 kg 100(-1) kg) but was reduced for the 100% rate (1.94 vs. 1.72 kg 100(-1) kg; P = 0.03; SEM = 0.11). Hay from the 75% rate was more digestible than hay from the 100% rate (527 vs. 508 g kg(-1); P = 0.03; SEM = 21). The SDI system functioned well, and lateral spacing did not alter hay quality. Treated waste from a raw waste treatment system was readily delivered by SDI at the recommended rate to produce bermudagrass hay of adequate quality for ruminant production systems.

Objectives: REP3123 is a fully synthetic methionyl-tRNA synthetase inhibitor in pre-clinical development as a novel agent to treat Clostridium difficile infection (CDI). This novel agent was investigated for its ability to block the production of toxins and spores, and was tested for efficacy in vivo in a hamster model., Methods: Clostridial toxin levels were determined qualitatively using monoclonal antibodies and by cytotoxicity assays. Spores were detected by staining and by quantitative dilution plating after ethanol treatment. Efficacy of REP3123 was tested in a clindamycin-induced C. difficile hamster gastrointestinal (GI) infection model., Results: REP3123 at concentrations as low as 1 mg/L inhibited de novo toxin production in high cell density, stationary phase cultures of C. difficile. Among comparator agents currently used for CDI therapy, vancomycin required much higher levels of 20 mg/L, and metronidazole had no effect on toxin levels. REP3123 caused a >10-fold reduction of the sporulation rate in vitro. Vancomycin and, in particular, metronidazole appeared to promote the formation of spores. REP3123, at concentrations as low as 0.5 mg/kg, demonstrated efficacy in the hamster model of CDI and was superior to vancomycin in the overall survival of the animals at the end of the study (33 days)., Conclusions: REP3123 inhibited growth of C. difficile, affected the production of toxins and spores and demonstrated superior efficacy compared with vancomycin in the hamster GI infection model. This agent may be a promising candidate for CDI treatment; in particular, the inhibition of toxin production and spore formation may reduce the severity and spread of the disease, respectively.

Sleep data were collected by maternal report in a prospective longitudinal follow up of cocaine-exposed and unexposed children. There were 139 participants: 23 with no prenatal drug exposure, 55 exposed to cocaine alone or in combination with other drugs, and 61 exposed to drugs other than cocaine. Characteristics differed between exposure groups including birth size, caretaker changes, maternal socioeconomic status, and postnatal drug use. Compared to those with no drug exposure, children with prenatal drug exposure other than cocaine experienced greater sleep problems (p = .026). Prenatal nicotine exposure was a unique predictor of sleep problems (p = .048). Early sleep problems predicted later sleep problems (all ps < .01). Together, these preliminary findings suggest possible neurotoxic sleep effects that persist over time. Larger studies, however, need to be conducted that better control for potential postnatal confounding factors.

The current review presents the empirical findings on varying definitions of nonrestorative sleep (NRS). Despite lacking a standard, operational definition, NRS is investigated in research studies and included in diagnostic manuals. However, because of the absence of standardization, the conclusions that can be drawn about NRS based on the current body of empirical literature are limited. A feeling of being unrefreshed upon awakening that is not accounted for by lack of sleep may occur among a substantial percentage of the population. This experience is correlated with daytime impairment, pain, fatigue, and electroencephalogram (EEG) arousals in non-REM sleep but causal links are unsubstantiated. An immediate converging of researchers toward NRS standardization is needed. We conclude that conceptualizing NRS as a primary symptom of insomnia on par with difficulty initiating sleep and difficulty maintaining sleep is empirically unsubstantiated. We recommend defining NRS as a report of persistently feeling unrefreshed upon awakening in the presence of a normal sleep duration, occurring in the absence of a sleep disorder.

Nonpoint source nitrogen is recognized as a significant water pollutant worldwide. One of the major contributors is agricultural drainage line water. A potential method of reducing this nitrogen discharge to water bodies is the use of immobilized denitrifying sludge (IDS). Our objectives were to (1) produce an effective IDS, (2) determine the IDS reaction kinetics in laboratory column bioreactors, and (3) test a field bioreactor for nitrogen removal from agricultural drainage line water. We developed a mixed liquor suspended solid (MLSS) denitrifying sludge using inoculant from an overland flow treatment system. It had a specific denitrification rate of 11.4 mg NO(3)-N g(-1) MLSS h(-1). We used polyvinyl alcohol (PVA) to immobilize this sludge and form IDS pellets. When placed in a 3.8-L column bioreactor, the IDS had a maximum removal rate (K(MAX)) of 3.64 mg NO(3)-N g(-1) pellet d(-1). In a field test with drainage water containing 7.8 mg NO(3)-N L(-1), 50% nitrogen removal was obtained with a 1 hr hydraulic retention time. Expressed as a 1 m(3) cubically-shaped bioreactor, the nitrogen removal rate would be 94 g NO(3)-N m(-2)d(-1), which is dramatically higher than treatment wetlands or passive carbonaceous bioreactors. IDS bioreactors offer potential for reducing nitrogen discharge from agricultural drainage lines. More research is needed to develop the bioreactors for agricultural use and to devise effective strategies for their implementation with other emerging technologies for improved water quality on both watershed and basin scales.

This study aimed to document the psychometric properties of the Beck Anxiety Inventory (BAI) within a population with sleep-disordered breathing (SDB), given concerns about overlapping symptomatology between anxiety and sleep apnea. Results supported good internal consistency and convergent and discriminant validity for the BAI and a single-factor solution for men, women, and the total sample. Women had higher scores than men, and discriminant analyses differentiated men from women based on item responses. The BAI has acceptable reliability and validity within a SDB population, supporting its use as a gauge of anxiety severity in individuals with SDB. This is a preliminary study to measure anxiety severity in SDB; future research is needed to determine the utility of the BAI as a diagnostic screener.

Faropenem was tested against 1,188 middle ear fluid pathogens from children in Israel and Costa Rica. Against Streptococcus pneumoniae and Haemophilus influenzae, faropenem was the most active beta-lactam, with activity that was similar to or greater than of the other oral antimicrobial classes studied. Faropenem was also active against Moraxella catarrhalis and Streptococcus pyogenes.

The ability of wetlands to retain P makes them an important landscape feature that buffers P movement. However, their P retention ability can be compromised through hydrologic disturbances caused by hurricanes and tropical storms (TS). This study had three objectives: (i) to determine the effects of hurricanes and TS on dissolved phosphorus (DP) concentrations and loads discharged from a Coastal Plain in-stream wetland (ISW); (ii) to evaluate shifts in P storage pools that would reflect P accretion/removal patterns; and (iii) to determine if relationships exist between storm characteristics with releases of DP and water volume. From January 1996 to October 1999, the ISW's outflow DP concentrations and flow volumes (Q) were measured and they were used to calculate DP mass export loads. In addition, the sediment total phosphorus (TP) concentrations were measured, and both the water column and sediment pore water DP concentrations were examined using passive samplers. In several instances, TS facilitated greater DP releases than a single hurricane event. The largest release of DP occurred in 1999 after Hurricanes Dennis, Floyd, and Irene. The large differences in DP exports among the storms were explained by Q variations. Storm activity also caused changes in sediment pore water DP and sediment TP concentrations. This study revealed that some TS events caused higher DP releases than a single hurricane; however, multiple hurricanes delivering heavy precipitation totals significantly increased DP export.

Aminoacyl-tRNA synthetases have attracted interest as essential and novel targets involved in bacterial protein synthesis. REP8839 is a potent inhibitor of MetS, the methionyl-tRNA synthetase in Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), and in Streptococcus pyogenes. The biochemical activity of REP8839 was shown by specific inhibition of purified S. aureus MetS (50% inhibitory concentration, <1.9 nM). Target specificity was confirmed by overexpression of the metS gene in S. aureus, resulting in an eightfold increase in the MIC for REP8839. Macromolecular synthesis assays in the presence of REP8839 demonstrated a dose-dependent inhibition of protein synthesis and RNA synthesis in S. pneumoniae R6, but only protein synthesis was affected in an isogenic rel mutant deficient in the stringent response. Strains with reduced susceptibility to REP8839 were generated by selection of strains with spontaneous mutations and through serial passages. Point mutations within the metS gene were mapped, leading to a total of 23 different amino acid substitutions within MetS that were located around the modeled active site. The most frequent MetS mutations were I57N, leading to a shift in the MIC from 0.06 microg/ml to 4 microg/ml, and G54S, resulting in a MIC of 32 microg/ml that was associated with a reduced growth rate. The mutation prevention concentration was 32 microg/ml in four S. aureus strains (methicillin-sensitive S. aureus and MRSA), which is well below the drug concentration of 2% (20,000 microg/ml) in a topical formulation. In conclusion, we demonstrate by biochemical, physiologic, and genetic mode-of-action studies that REP8839 exerts its antibacterial activity through specific inhibition of MetS, a novel target.

REP8839 is a novel methionyl-tRNA synthetase (MetS) inhibitor with potent antibacterial activity against clinical isolates of Staphylococcus aureus, Streptococcus pyogenes, and other clinically important gram-positive bacteria but little activity against gram-negative bacteria. All isolates of S. aureus, including strains resistant to methicillin, mupirocin, vancomycin, and linezolid were susceptible to REP8839 at concentrations of < or =0.5 microg/ml. REP8839 was also active against Staphylococcus epidermidis, including multiply resistant strains (MIC, < or =0.25 microg/ml). All S. pyogenes isolates were susceptible to REP8839 at concentrations of < or =0.25 microg/ml, suggesting that MetS2, a second enzyme previously identified in Streptococcus pneumoniae, was not present in this organism. REP8839 was highly bound to the protein of human serum, and activity was not greatly influenced by inoculum size but was affected by pH, exhibiting optimal antibacterial activity in a neutral medium rather than a weak acidic medium. Like mupirocin, REP8839 exhibited bacteriostatic activity against key pathogens. The emergence of mupirocin resistance in S. aureus highlights the need for a new topical antibiotic with the ability to inhibit high-level mupirocin-resistant strains and other emerging phenotypes, such as vancomycin-resistant and community-acquired methicillin-resistant isolates.

Riparian zones are recognized as landscape features that buffer streams from pollutants, particularly nitrogen. The objectives of this experiment were to (i) assess denitrification activity within a riparian zone and (ii) determine the influence of physical, chemical, and landscape features on denitrification. This experiment was conducted from 1994 to 1997 in North Carolina on a riparian zone contiguous to a spray field that was heavily loaded with swine lagoon wastewater. Denitrification enzyme activity (DEA) was measured on soils collected from (i) the soil surface, (ii) midway between the soil surface and water table, and (iii) above the water table. The DEA ranged from 3 to 1660 microg N(2)O-N kg(-1) soil h(-1). The DEA was highest next to the stream and lowest next to the spray field. Nitrate was found to be the limiting factor for denitrification. The DEA generally decreased with soil depth; means for the surface, middle, and bottom depths were 147, 83, and 67 microg N(2)O-N kg(-1) soil h(-1), respectively. These DEA values are higher than those reported for riparian zones adjoining cropland of the southeastern United States, but are lower than those reported for a constructed wetland used for treatment of swine wastewater. Regression analysis indicated that soil total nitrogen was the highest single factor correlated to DEA (r(2) = 0.65). The inclusion of water table depth, soil depth, and distance from the spray field improved the R(2) to 0.86. This riparian zone possessed sufficient soil area with high denitrifying conditions to be a significant factor in the removal of excess nitrogen in the ground water.

Ammonia (NH3) volatilization is an undesirable mechanism for the removal of nitrogen (N) from wastewater treatment wetlands. To minimize the potential for NH3 volatilization, it is important to determine how wetland design affects NH3 volatilization. The objective of this research was to determine how the presence of a pond section affects NH3 volatilization from constructed wetlands treating wastewater from a confined swine operation. Wastewater was added at different N loads to six constructed wetlands of the marsh-pond-marsh design that were located in Greensboro, North Carolina, USA. A large enclosure was used to measure NH3 volatilization from the marsh and pond sections of each wetland in July and August of 2001. Ammonia volatilized from marsh and pond sections at rates ranging from 5 to 102 mg NH3-N m(-2) h(-1). Pond sections exhibited a significantly greater increase in the rate of NH3 volatilization (p < 0.0001) than did either marsh section as N load increased. At N loads greater than 15 kg ha(-1) d(-1), NH3 volatilization accounted for 23 to 36% of the N load. Furthermore, NH3 volatilization was the dominant (54-79%) N removal mechanism at N loads greater than 15 kg ha(-1) d(-1). Without the pond sections, NH3 volatilization would have been a minor contributor (less than 12%) to the N balance of these wetlands. To minimize NH3 volatilization, continuous marsh systems should be preferred over marsh-pond-marsh systems for the treatment of wastewater from confined animal operations.

Dissolved phosphorus (DP) can be released from wetlands as a result of flooding or shifts in water column concentrations. Our objectives were to determine the long-term (1460 d) DP retention and release characteristics of an in-stream wetland, and to evaluate how these characteristics respond to flooding, draining, and changes in DP concentrations. The studied in-stream wetland drains an agriculturally intensive subwatershed in the North Carolina Coastal Plain region. The wetland's DP retention and release characteristics were evaluated by measuring inflow and outflow DP concentrations, DP mass balance, and DP movement across the sediment-water column interface. Phosphorus sorption isotherms were measured to determine the sediment's equilibria P concentration (EPCo), and passive samplers were used to measure sediment pore water DP concentrations. Initially, the in-stream wetland was undersized (0.31 ha) and released 1.5 kg of DP. Increasing the in-stream wetland area to 0.67 ha by flooding resulted in more DP retention (28 kg) and low outflow DP concentrations. Draining the in-stream wetland from 0.67 to 0.33 ha caused the release of stored DP (12.1 kg). Shifts both in sediment pore water DP concentrations and sediment EPCo values corroborate the release of stored DP. Reflooding the wetland from 0.33 to 0.85 ha caused additional release of stored DP into the outflowing stream (10.9 kg). We conclude that for a time period, this in-stream wetland did provide DP retention. During other time periods, DP was released due to changes in wetland area, rainfall, and DP concentrations.

Flavocytochrome b (Cyt b) is a heterodimeric, integral membrane protein that serves as the central component of an electron transferase system employed by phagocytes for elimination of bacterial and fungal pathogens. This report describes a rapid and efficient single-step purification of Cyt b from human neutrophil plasma membranes by solubilization in the nonionic detergent dodecylmaltoside (DDM) and immunoaffinity chromatography. A similar procedure for isolation of Cyt b directly from intact neutrophils by a combination of heparin and immunoaffinity chromatography is also presented. The stability of Cyt b was enhanced in DDM relative to previously employed solubilizing agents as determined by both monitoring the heme spectrum in crude membrane extracts and assaying resistance to proteolytic degradation following purification. Gel filtration chromatography and dynamic light scattering indicated that DDM maintains a predominantly monodisperse population of Cyt b following immunoaffinity purification. The high degree of purity obtained with this isolation procedure allowed for direct determination of a 2:1 heme to protein stoichiometry, confirming previous structural models. Analysis of the isolated heterodimer by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry allowed for accurate mass determination of p22(phox) as indicated by the gene sequence. Affinity-purified Cyt b was functionally reconstituted into artificial bilayers and demonstrated that catalytic activity of the protein was efficiently retained throughout the purification procedure.

Subcellular fractionation of human neutrophils on linear sucrose density gradients was utilized to test the hypothesis that priming regulates the subcellular and sub-plasma membrane distribution of neutrophil G-protein subunits, G(ialpha2) and G(ialpha3), N-formyl peptide receptor, Lyn kinase and phospholipase C(beta2). G(ialpha2), but not G(ialpha3), moved from a lighter to a higher density plasma membrane fraction. Unoccupied N-formyl peptide receptors were found throughout the plasma membrane fractions and this distribution did not change with priming. In unprimed cells G(ialpha2) and its effector, phospholipase C(beta2), were segregated in different membrane compartments; priming caused G(ialpha2) to move to the compartment in which phospholipase C(beta2) resided. Thus, an important component of the mechanism of priming may involve regulation of the location of G-proteins and effector molecules in plasma membrane compartments where their abilities to couple may be enhanced.

During an 18-month (1994-1995) survey of the surface water in an Atlantic Coastal Plain watershed, metolachlor was most frequently detected during storm flow events. Therefore, a sampling procedure, focused on storm flow, was implemented in June of 1996. During 1996, three tropical cyclones made landfall within 150 km of the watershed. These storms, as well as several summer thunderstorms, produced six distinct storm flow events within the watershed. Metolachlor was detected leaving the watershed during each event. In early September, Hurricane Fran produced the largest storm flow event and accounted for the majority of the metolachlor exports. During the storm event triggered by Hurricane Fran, the highest daily average flow (7.5 m2 s-1) and highest concentration (5.1 micrograms L-1) ever measured at the watershed outlet were recorded. Storm flow exports leaving the watershed represented 0.1 g ha-1 or about 0.04% of active ingredient applied.

Phage-display peptide library analysis of an anti-F actin polyclonal antibody identified 12 amino acid residues of actin that appear, in its X-ray crystal structure, to be grouped together in a surface accessible conformational epitope. Phage epitope mapping was carried out by isolating immune complexes containing members of the J404 nonapeptide phage-display library formed in diluted antiserum and isolated on a protein A affinity matrix. Immunoreactive clones were grown as plaques, replica plated onto nitrocellulose, and labeled with anti-actin immune serum. One hundred and forty-four positively staining clones identified in this way were sequenced. Of these, 54 displayed peptides with sequence similarities. When the most abundantly selected sequence, KQTWQQLWD, was produced as a synthetic peptide and derivatized to ovalbumin, the complex was strongly recognized by the antiserum on Western blots and inhibited the binding of the antibody to immobilized F-actin by 60%. A scrambled version of this sequence WQDK WLQTQ, when coupled to ovalbumin, was not recognized by the antiserum and minimally inhibited binding of antiserum to immobilized F-actin by 10%. KQTWQQLWD contained four residues that corresponded, in frame, to a highly conserved six residue region of the chicken beta-actin sequence 351TFQQMW356 (identical residues are shown in bold). Examination of the rabbit skeletal muscle X-ray crystal structure suggested that within a 15 A radius of W356, nine additional residues were arranged on the actin surface in such a way that they could be mimicked by several of the selected phage sequences with root-mean-square deviation fits of 2.1-2.5 A. We conclude that phage-display analysis can provide information about the relative location of amino acids on the surfaces of proteins using antibody imprints of the protein surface structure.

Although total cell number has been determined for the alveolar region of the lungs of many species, it has not been calculated for the nonalveolar lung tissues. The oriented structure of airways and vessels makes the numerical assessment of cells in nonalveolar tissues difficult. This has led many investigators to use the number of cells in the alveolar region as a direct estimate of total lung cell number. To determine the number of cells in the nonalveolar lung tissues, the lungs of eight rats weighing 230 to 380 g were inflation-fixed and embedded in araldite, and 1.5-microns serial sections of the entire left lobe were cut and stained with methylene blue for light microscopy. The sections were then uniformly point-counted using computer-controlled distances between the fields to determine the fraction of points falling on air, blood, cellular tissue, and noncellular tissue for both the alveolar and the nonalveolar regions. The total volume of cell nuclei in each compartment was determined, and the total number of cells was calculated by dividing the total nuclear volume by the mean cell nuclear volume. It was found that 87% of the lung volume was alveolar, of which 6% was tissue and contained 725 x 10(6) cells. The nonalveolar region constituted 13% of the lung volume, of which 23% was tissue and contained 250 x 10(6) cells. The average rat lung therefore contains 975,000,000 cells, of which 74% was in alveolar tissues and 26% in nonalveolar tissues. On the basis of assays of isolated lung cells, there is an average of 7 pg DNA/cell.(ABSTRACT TRUNCATED AT 250 WORDS)

Allometric studies have shown that lung volume, alveolar surface area, and diffusing capacity increase proportionally with body weight across a broad range of mammalian species. Changes in the number of cells and in average cell size and surface areas with increasing body weight have not been defined. We speculated that cell size is determined more by cell function than by species and body weight. To test this hypothesis, nine species ranging in size from shrew (2 to 3 g) to horse (510 kg) were studied. Random sites from the distal alveolar region of each species were analyzed using morphometric techniques. Six to 10 nuclei from each of the major classes of parenchymal lung cells were three-dimensionally reconstructed to determine their average diameter, volume, and surface area. To calculate the cell density, nuclear profiles were counted using electron microscopy. The number of cells per lung increased with body mass and lung volume with a slope of 1.01 (r2 = 0.99). The lung is unique among organs in the diversity and function of individual cell types, such as mechanical, sensory, secretory, transporting, and circulating cells. Excluding the circulatory cells, the lung has greater than 60 different cell types, making it an ideal organ for examining the varieties in cell characteristics across different species. Up to 6-fold differences in size were found between different lung cell types within a single species; however, for cells having secretory functions, such as type II cells, there was no detectable change in cell size with increasing lung surface area or body mass.(ABSTRACT TRUNCATED AT 250 WORDS)

A data-based cost-consciousness curriculum was developed that stresses teaching by community physician preceptors in their own practice settings, using an educational packet that incorporates the teaching practice's own data. The cost awareness program represents an educational application of an interpractice medical information system developed by the Primary Care Cooperative Information Project (COOP Project). This system allows patients to be tracked longitudinally within a practice and enables cross-practice comparisons of process, outcomes, and costs for similar cohorts of patients. Initial experiences during the pilot year suggest that the use of practice-based data by physician preceptors is a sound strategy, giving the preceptors flexibility in tailoring their approach to specific teaching/learning situations. Student and preceptor reaction was generally positive. Cost issues are threatening to physicians and it is appropriate to design educational strategies which allow physician preceptors to articulate their perspectives. As role models for medical students, preceptors are in an excellent position to influence physicians in training to be more cost conscious as physicians.