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Seasonal cycles within the marginal ice zones in polar regions include large shifts in temperature and salinity that strongly influence microbial abundance and physiology. However, the combined effects of concurrent temperature and salinity change on microbial community structure and biochemical composition during transitions between seawater and sea ice are not well understood. Coastal marine communities along the western Antarctic Peninsula were sampled and surface seawater was incubated at combinations of temperature and salinity mimicking the formation (cold, salty) and melting (warm, fresh) of sea ice to evaluate how these factors may shape community composition and particulate metabolite pools during seasonal transitions. Bacterial and algal community structures were tightly coupled to each other and distinct across sea-ice, seawater, and sea-ice-meltwater field samples, with unique metabolite profiles in each habitat. During short-term (approximately 10-day) incubations of seawater microbial communities under different temperature and salinity conditions, community compositions changed minimally while metabolite pools shifted greatly, strongly accumulating compatible solutes like proline and glycine betaine under cold and salty conditions. Lower salinities reduced total metabolite concentrations in particulate matter, which may indicate a release of metabolites into the labile dissolved organic matter pool. Low salinity also increased acylcarnitine concentrations in particulate matter, suggesting a potential for fatty acid degradation and reduced nutritional value at the base of the food web during freshening. Our findings have consequences for food web dynamics, microbial interactions, and carbon cycling as polar regions undergo rapid climate change.

The various functions of the sobriety checkpoint program by Fairfax County, are discussed. The initial technological drawbacks and the solutions for those, to implement the sobriety checkpoint program successfully for the safe driving and reducing the number of accidents, are also discussed. The future aspects of this policy are also mentioned.

Among the many new technologies in traffic law enforcement, the traffic radar is one, which has come under many attacks, tests and scrutiny. But the traffic radar has proven to be very effective if used in accordance with the manufacturer's instructions by trained officers.

We studied cardiac complications in young persons with severe acute respiratory syndrome coronavirus 2. In a prospective cohort of 127 Military Health System beneficiaries 0–22 years old, 3.1% had cardiac abnormalities, all resolved within 6 months. Our findings support guidelines against routine cardiac screening in mild COVID-19 cases without cardiac symptoms.

Presents letters to the editor. View that the U.S. invasion of Iraq has only angered the Arab world, is breeding future terrorists, and widening the danger to America; View that the United States is more prepared and better protected against the terrorist threat than ever before; Concern that the U.S. government is spending more money per capita to protect residents of Utah than New Yorkers; Other letters.

Exposure to environmental chemicals has adverse effects on the health and survival of humans. Emerging evidence supports the idea that exposure to endocrine-disrupting compounds (EDCs) can perturb an individual’s physiological set point and as a result increase his/her propensity toward several diseases. The purpose of this review is to provide an update on di-(2-ethylhexyl) phthalate, the primary plasticizer found in plastic medical devices used in neonatal intensive care units, its effects on the fetus and newborn, epidemiological studies, pharmacokinetics, toxicity and epigenetic implications. We searched the PubMed databases to identify relevant studies. Phthalates are known EDCs that primarily are used to improve the flexibility of polyvinyl chloride plastic products and are called plasticizers in lay terms. Neonates and infants are particularly vulnerable to the effects of phthalates, beginning with maternal exposure and placental transfer during gestation and during infancy following birth. In line with the developmental origins of adult disease, a focus on the effects of environmental chemicals in uteroor early childhood on the genesis of adult diseases through epigenome modulation is timely and important. The epigenetic effects of phthalates have not been fully elucidated, but accumulating evidence suggests that they may be associated with adverse health effects, some of which may be heritable. Phthalate exposure during pregnancy and the perinatal period is particularly worrisome in health-care settings. Although the clinical significance of phthalate exposure has been difficult to assess with epidemiologic studies, the evidence that physiological changes occur due to exposure to phthalates is growing and points toward the need for more investigation at a molecular, specifically epigenetic level.

We assessed satellite‐retrieved marine aerosol in the western Antarctic Peninsula (WAP) across a 12‐year period from coarse‐mode aerosol optical depth (AODC), often used as a proxy for sea spray aerosol (SSA), and marine aerosol optical depth (MAOD), a newly developed proxy for tropospheric marine aerosol. Across open ocean to coastal regions, daily fluctuations in nighttime and daytime winds, respectively, drove increasing MAOD and AODC. MAOD depicted strong correlations with wind speed across open ocean and weak correlations in coastal regions. In the open ocean, AODCexhibited a very weak significant correlation to wind speed and a weak significant correlation to sea surface temperature (SST). We thus observed that warmer SST enhanced the production of SSA, supporting prior studies. This is the first study to assess patterns of AODCin the WAP. In contrast to the tropical Pacific, seasonal patterns showed that biological activity likely contributed toward MAOD and AODCmagnitudes. The production of marine aerosol in the Bellingshausen Sea of the western Antarctic is coupled to the environment. Processes driving marine aerosol include wind speed, which produces sea spray aerosol (SSA), sea surface temperature (SST), which can enhance the production of SSA, and seasonal dynamics of sea ice melt and phytoplankton blooms, which can contribute to production of biogenic sources of marine aerosol. To study these drivers in closer detail, we used two specialized proxies of marine aerosol concentration: coarse‐mode Aerosol Optical Depth (AODC), a proxy for SSA, and Marine Aerosol Optical Depth (MAOD) a proxy for low‐altitude marine aerosol. We examined MAOD and AODCfrom 2007 to 2018 and found that wind speed was a driver of day‐to‐day fluxes in marine aerosol. In contrast to the tropical Pacific in which enhanced biological activity suppresses SSA particle production, we did not observe lessening of MAOD and AODCmagnitudes during the biologically productive austral summertime. In fact, summertime MAOD exhibited a weak significant correlation to daily wind speed in the coastal ocean despite a lack of significance in wintertime. This work enriches our knowledge of biotic and abiotic drivers of marine aerosol in high‐latitude environments. The open ocean and coastal Bellingshausen Sea show weak correlations of marine aerosol optical depth (MAOD) to daily windsAODCexhibits weak correlations to sea surface temperature (SST) in the open ocean and very weak correlations to daily wind speed across all regionsSeasonal increases in MAOD dependence on daily wind speed is likely associated with higher biological activity in summer The open ocean and coastal Bellingshausen Sea show weak correlations of marine aerosol optical depth (MAOD) to daily winds AODCexhibits weak correlations to sea surface temperature (SST) in the open ocean and very weak correlations to daily wind speed across all regions Seasonal increases in MAOD dependence on daily wind speed is likely associated with higher biological activity in summer

Aims. We describe an ab initio-based numerical method of obtaining infrared spectroscopic data (line list) of polyatomic molecules that allows calculation of complete sets of lines for temperatures up to several thousand Kelvin. While the main focus is on completeness and consistency, not spectroscopic accuracy, the approach is in principle “exact” for line positions and, although not exact for line strengths, of sufficient accuracy to be of value, especially in wavelength regions where there are gaps in reliable experimental data.

Context.A recent modeling study of brightness ratios for CO rotational transitions in gas typical of the diffuse ISM by Liszt found the role of H collisions to be more important than previously assumed. This conclusion was based on recent quantum scattering calculations using the so-called WKS potential energy surface (PES) which reported a large cross section for the important 0$\rightarrow$1 rotational transition. This result is in contradiction to one obtained using the earlier BBH PES for which the cross section is quite small and which is consistent with an expected homonuclear-like propensity for even $\Delta J$transitions.

Previous studies have suggested that the attenuation of Canada lynx (Lynx canadensis) cyclic dynamics with decreasing latitude may be the consequence of a reduced specialization on the lynx’s primary prey, snowshoe hares (Lepus americanus). However, intraguild competitive interactions remain largely unexplored in situations where the temporal dynamics of food resources is pronounced, and lynx populations in the south of their distribution may be negatively affected by interspecific competition with other carnivores. In this paper, we used spectral analysis of fur harvest data collected at the state (US) and province (Canada) level to explore the spatial gradient of cyclic dynamics in lynx. Although some patterns were consistent with the ‘diet specialization’ hypothesis, we found that temporal variance of cycling propensity peaked at mid-latitudes, where transient, non-cyclic periods, coexisted with regular 10-year cycles. In these mid-latitude zones, non-cyclic periods did not coincide with loss of snowshoe hare cycling as demonstrated by historical records, and were not more frequent in recent decades as could be expected under a ‘climatic forcing’ scenario. Instead, we show that non-cyclic periods tended to coincide with periods of high coyote (Canis latrans) abundance and periods when coyotes apparently tracked snowshoe hare abundance as suggested by significant 10-year cycles lagging one or two years behind hare peaks. We used landscape-scale (trapline) fur harvest returns from five provinces in Canada to further probe the importance of interspecific competition in Canada lynx population dynamics. Accounting for coyote distribution and abundance did not bring additional explanatory and predictive power to models based solely on environmental and autecological predictors, suggesting that competition with coyote is not a force driving population abundance and cyclicity among lynx. We discuss the possible factors behind the apparent lack of consistency across spatial scales and recommend that further studies examine species interactions at a smaller (local) scale.

Ionization of the Earth's atmosphere by sunlight forms a complex, multilayered plasma environment within the Earth's magnetosphere, the innermost layers being the ionosphere and plasmasphere. The plasmasphere is believed to be embedded with cylindrical density structures (ducts) aligned along the Earth's magnetic field, but direct evidence for these remains scarce. Here we report the first direct wide‐angle observation of an extensive array of field‐aligned ducts bridging the upper ionosphere and inner plasmasphere, using a novel ground‐based imaging technique. We establish their heights and motions by feature tracking and parallax analysis. The structures are strikingly organized, appearing as regularly spaced, alternating tubes of overdensities and underdensities strongly aligned with the Earth's magnetic field. These findings represent the first direct visual evidence for the existence of such structures. Vast arrays of regularly spaced, field‐aligned ducts are common at midlatitudesWidefield, low‐frequency radio telescopes are powerful probes of the ionosphereNew imaging technique allows regional‐scale monitoring of plasma dynamics in 3‐D

ABSTRACTNontypeable Haemophilus influenzae(NTHI) strains are responsible for respiratory-related infections which cause a significant burden of disease in Australian children. We previously identified a disparity in NTHI culture-defined carriage rates between Aboriginal and non-Aboriginal children (42% versus 11%). The aim of this study was to use molecular techniques to accurately determine the true NTHI carriage rates (excluding other culture-identical Haemophilusspp.) and assess whether the NTHI strain diversity correlates with the disparity in NTHI carriage rates. NTHI isolates were cultured from 595 nasopharyngeal aspirates collected longitudinally from asymptomatic Aboriginal (n= 81) and non-Aboriginal (n= 76) children aged 0 to 2 years living in the Kalgoorlie-Boulder region, Western Australia. NTHI-specific 16S rRNA gene PCR and PCR ribotyping were conducted on these isolates. Confirmation of NTHI by 16S rRNA gene PCR corrected the NTHI carriage rates from 42% to 36% in Aboriginal children and from 11% to 9% in non-Aboriginal children. A total of 75 different NTHI ribotypes were identified, with 51% unique to Aboriginal children and 13% unique to non-Aboriginal children (P< 0.0001). The strain richness (proportion of different NTHI ribotypes) was similar for Aboriginal (19%, 65/346) and non-Aboriginal children (19%, 37/192) (P= 0.909). Persistent carriage of the same ribotype was rare in the two groups, but colonization with multiple NTHI strains was more common in Aboriginal children than in non-Aboriginal children. True NTHI carriage was less than that estimated by culture. The Aboriginal children were more likely to carry unique and multiple NTHI strains, which may contribute to the chronicity of NTHI colonization and subsequent disease.

The Murchison Wide-Field Array (MWA) is a low-frequency radio telescope, currently under construction, intended to search for the spectral signature of the epoch of reionization (EOR) and to probe the structure of the solar corona. Sited in western Australia, the full MWA will comprise 8192 dipoles grouped into 512 tiles and will be capable of imaging the sky south of 40° declination, from 80 MHz to 300 MHz with an instantaneous field of view that is tens of degrees wide and a resolution of a few arcminutes. A 32 station prototype of the MWA has been recently commissioned and a set of observations has been taken that exercise the whole acquisition and processing pipeline. We present Stokes  I, Q, and Uimages from two ?4 hr integrations of a field 20° wide centered on Pictoris A. These images demonstrate the capacity and stability of a real-time calibration and imaging technique employing the weighted addition of warped snapshots to counter extreme wide-field imaging distortions.

The primary sources of mycotoxins that can potentially contaminate beer include contaminated malt or adjunct grains used in malting and brewing. Australia typically has a dry climate during barley harvest that results in dry barley for storage. However, screening for quality assurance purposes is still required because of the unlikely event of barley infection by fungal species, from which harmful mycotoxins can accumulate. Quality control protocols require that malting barley be free of mycotoxins such as deoxynivalenol (DON) and ochratoxin A (OTA). Immunoaffinity columns (IACs) are widely used to isolate mycotoxins from barley, malt, and feed, followed by quantification by either HPLC or fluorometry. Mycotoxin analysis procedures are relatively easy to use, rapid, accurate, and toxin specific, but expensive. The repeated reuse of DON and OTA IACs assists in reducing the cost of mycotoxin analysis without compromising safety, especially when the occurrence of these mycotoxins is rare, such as with Australian malt and barley.

Aims. We describe an ab?initio-based numerical method of obtaining infrared spectroscopic data (line list) of polyatomic molecules that allows calculation of complete sets of lines for temperatures up to several thousand Kelvin. While the main focus is on completeness and consistency, not spectroscopic accuracy, the approach is in principle ?exact? for line positions and, although not exact for line strengths, of sufficient accuracy to be of value, especially in wavelength regions where there are gaps in reliable experimental data.Methods. Global potential energy and dipole moment hypersurfaces are fitted to the results of ab?initio electronic structure calculations. The MULTIMODE software is then used to obtain rovibrational energy levels and dipole transition matrix elements. This information is used to calculate a complete set of Einstein coefficients of spontaneous emission Aij.Results. The method is applied to obtain a spectroscopic database for methane containing over 1.4 million lines up to an upper state energy of 6200?cm-1( ?9000?K). The emission spectrum of CH4at 1000?K is calculated with the complete set of Einstein coefficients and compared with the one obtained from the HITRAN database. Gaps in the database are realistically filled in by the calculated spectrum.Conclusions. Consistent and complete databases are important for astrophysical applications. Databases obtained by the method described here fulfill this requirement and are sufficiently accurate for astrophysical applications such as model atmosphere calculations and the corresponding synthetic spectra.

Barley head row type is a major trait affecting end-use quality. Six-rowed forms emerged due to mutations in the Vrs1gene in two-rowed barleys. Whether barley is two (Vrs1) or six rowed (vrs1) directly affects a wide range of morphological traits related to seed yield and grain quality. Vrs1has been cloned and encodes a homeodomain transcription factor with a linked leucine zipper motif. To test the association between Vrs1alleles and grain quality, we characterized the Vrs1alleles among a well-described collection of 81 spring barley accessions selected for divergence in head type and dry matter digestibility (DMD). The results indicated that the majority of two-rowed barleys have the Vrs1.b3-1allele and the majority of six-rowed barleys carry the vrs1.a1-8allele. In comparison with two-rowed barleys, six-rowed barleys were more variable in grain hardness. This divergence in hardness values was associated with specific vrs1alleles, with barley accessions carrying the less severe amino acid missense mutation VRS1.a3-1 isoform being softer and having higher DMD than those accessions carrying the more common VRS1.a1-1 amino acid frameshift isoform. The assignment of six-rowed barley cultivars to different vrs1allele groups may prove beneficial for the selection of specific grain-quality parameters.

The Hardness(Ha) locus contains the Hina, Hinb‐1, Hinb‐2, and Gspgenes and was shown to be associated with grain hardness and dry matter digestibility (DMD) variation. In this study, 73 spring barley (Hordeum vulgareL.) accessions selected for DMD variation were assessed for variation in DMD, seed quality, and Hardness(Ha) locus component gene alleles. To determine whether Hais associated with grain quality traits, we assessed the relationship of the Halocus in the presence or absence of head type (two or six row) variation. To accomplish this, the barley Halocus component genes (Hina, Hinb‐1, Hinb‐2, and Gsp) were sequenced from each accession and sorted by prevalence. The most common Hahaplotype (HINA, HINB‐1, HINB‐2 alleles) was present in 42 accessions with the remaining 39 dispersed over 24 haplotypes. Seeds from two‐row accessions with the most common Hahaplotype were significantly softer in grain texture (P< 0.001) and had increased starch content (P< 0.001) and DMD (P< 0.05). We used quantitative reverse‐transcriptase polymerase chain reaction to measure Hina, Hinb‐1, Hinb‐2, and Gspexpression levels in developing seeds of 19 Halocus haplotypes. The expression levels of all four genes were positively correlated with DMD. The results indicate that selection for individual Halocus haplotypes may be useful in modifying seed size, DMD, and starch content in two‐row barley.

Two experiments were conducted to evaluate digestion kinetics of alfalfa (Medicago sativaL.) substitution for grass hay in beef cattle. In Exp. 1, forage combinations evaluated in situ consisted of 0% alfalfa-100% big bluestem (Andropogon gerardiVitman), 25% alfalfa-75% big bluestem, 50% alfalfa-50% big bluestem, and 100% alfalfa-0% big bluestem. Nonlinear regression was used to determine the immediately soluble fraction A, the potentially degradable fraction B, the undegraded fraction C, and the disappearance rate of DM and NDF. Dry matter fraction Aincreased linearly (P= 0.03), and DM and NDF fraction Bdecreased linearly (P= 0.01) with increasing alfalfa substitution. Rate of DM and NDF disappearance increased linearly (P≤ 0.02) with increasing alfalfa substitution. In Exp. 2, treatments were arranged as a 2 × 2 factorial testing alfalfa substitution [none or 25% (as-fed basis)] to orchardgrass hay (Dactylis glomerataL.) and intake level [restricted to 1% of BW daily (DM basis) or ad libitum]. Nutrient intakes were lowest (P≤ 0.05) by steers fed restricted diets, intermediate by steers fed orchardgrass ad libitum, and greatest by steers fed orchardgrass plus alfalfa ad libitum. Intake level and forage source had no effect (P≥ 0.23) on total tract apparent digestibility of all nutrients except CP. Steers fed orchardgrass plus alfalfa had 33% greater (P= 0.01) total tract apparent digestibility for CP than those fed orchardgrass alone. Lag time of DM and NDF disappearance was not affected (P≥ 0.20) by alfalfa supplementation or intake level. Rate of DM and NDF disappearance of orchardgrass was faster (P≤ 0.01) in steers fed orchardgrass plus alfalfa, at both restricted and ad libitum levels of feeding, than in animals fed orchardgrass alone. Mean retention times of large and small particles of orchardgrass tended to be shorter (P≤ 0.06) when steers consumed ad libitum vs. restricted diets. Small orchardgrass particles tended to have a faster (P= 0.09) rate of passage under ad libitum feeding conditions and with alfalfa addition. Ad libitum intake was associated with a shorter mean retention time of orchardgrass and faster rate of passage of small orchardgrass particles, whereas alfalfa addition increased the rate of passage of small orchardgrass particles and the rate of DM and NDF disappearance.

ABSTRACTThe echinocandin caspofungin is a potent inhibitor of the activity of 1,3-β-d-glucan synthase from Aspergillus flavus, Aspergillus terreus, and Aspergillus nidulans. In murine models of disseminated infection, caspofungin prolonged survival and reduced the kidney fungal burden. Caspofungin was at least as effective as amphotericin B against these filamentous fungi in vivo.

Starch is the primary nutrient in ruminant diets used to promote high levels of performance. The site of starch digestion alters the nature of digestive end products (VFA in the rumen vs. glucose in the small intestine) and the efficiency of use. Cereal grain endosperm texture plays a major role in the rate and extent of starch degradation in ruminants. Wheat grain texture is regulated by the starch surface protein complex friabilin that consists primarily of puroindoline (PIN) A and B. Soft kernel texture in wheat is a result of both PIN genes being in the wild type active form and bound to starch. The objective of this study was to investigate the effect of varying PIN content in wheat on the rate of starch digestion in the rumen of beef cattle. In Exp. 1, 6 transgenic soft pin a/bisolines created in a hard wheat background, and 2 hard wheat controls were milled to yield a wide range of mean particle sizes across all lines. Milled samples were incubated in situ for 3 h. Increased expression of both PINA and PINB decreased DM digestibility (DMD) by 29.2% (P< 0.05) and decreased starch digestibility by 30.8% (P< 0.05). Experiment 2 separated the effects of particle size and total PIN content on digestion by milling the hardest and softest lines such that the mean particle size was nearly identical. Increased PIN decreased DMD by 21.7% (P< 0.05) and starch digestibility by 19.9% (P< 0.05) across particle sizes smaller than whole kernel. Experiment 3 addressed the time course of PIN effects in the rumen by observing ground samples of the hardest and softest lines over a 12-h in situ period. Increased PIN decreased DMD by 10.4% (P< 0.05) and starch digestibility by 11.0% (P< 0.05) across all time points. Dry matter and starch digestibility results demonstrated that increased expression of PIN was associated with a decreased rate of ruminal digestion independent of particle size. Puroindolines seem to aid in the protection of starch molecules from microbial digestion in the rumen, potentially increasing the amount of starch entering the small intestine.

A digestion study with 28 yearling heifers (428 ± 9.9 kg; Exp. 1) and a 2-yr winter grazing trial with 60 crossbred cows (552 ± 6.9 kg; Exp. 2) were used to determine the effects of level of nonstructural carbohydrate (NSC) supplementation on intake and digestibility of low-quality forage. Treatments were as follows: 1) control, no supplement; 2) 0.32 kg of NSC (1.8 kg/d of soybean hulls and soybean meal; DM basis); 3) 0.64 kg of NSC (1.7 kg/d of wheat middlings; DM basis); and 4) 0.96 kg of NSC (1.7 kg/d of barley and soybean meal; DM basis). Supplements provided 0.34 kg of CP/d and 5.1 Mcal of ME/d. In Exp. 1, heifers were individually fed hay (5.5% CP, DM basis) and their respective supplements in Calan gates for 28 d. Data were analyzed as a completely randomized design. In Exp. 2, cows were individually fed supplement on alternate days, and grazed a single rangeland pasture stocked at 1.8 ha/animal unit month. Two ruminally cannulated cows were used per treatment to obtain forage extrusa and to measure in situ DM disappearance (DMD) and carboxymethylcellulase (CMCase) activity of particle-associated ruminal microbes. Data were analyzed as a completely randomized design with the effects of treatment, year, and their interaction. In both experiments, Cr2O3boluses were used to determine fecal output, individual animal was the experimental unit, and contrasts were used to test linear and quadratic effects of NSC level and control vs. supplemented treatments. In Exp. 1, hay and diet DM, NDF, and CP intakes and digestibilities were increased (P< 0.01) by NSC supplementation compared with the control. In Exp. 2, 72-h in situ DMD and CMCase were decreased linearly (P< 0.08) with increasing NSC supplementation. Intake of forage DM, NDF, and CP was decreased linearly (P< 0.01) with increasing NSC supplementation during both years. Supplementation with NSC decreased (P= 0.01) cow BW loss compared with the control in yr 1, whereas in yr 2, cow BW loss was linearly increased (P= 0.03) by increasing NSC supplementation. Supplements containing NSC improved forage digestion and intake when heifers consumed forage deficient in CP relative to energy (digestible OM:CP > 7), but decreased forage digestion and intake when cows grazed forage with adequate CP relative to energy (digestible OM:CP < 7). Forage and supplement digestible OM:CP seemed to be superior predictors of response to supplementation with NSC compared with forage CP levels alone.

This study evaluated the effect of barley varieties in the diets of finishing steers on carcass composition, fat, and lean color and the fatty acid profile of subcutaneous fat. Crossbred steers (391 kg initial BW) were assigned randomly to one of five finishing diets composed primarily of corn (n = 9), Morex barley (n = 9), Steptoe barley, (n = 9), or two experimental barley varieties SM3 (n = 9) and SM5 (n = 9). Grains were cracked prior to feeding. Diets were formulated (DM basis) to be isonitrogenous (2.24% N) and isocaloric (2.01 Mcal/kg NEmand 1.35 Mcal/kg NEg). Steers were slaughtered according to industry-accepted procedures when it was visually estimated that 70% of carcasses would grade USDA Choice. After a 24-h chill at 4°C, carcass quality and yield grade data were collected by trained, experienced university personnel. Objective color (L*, a*, and b*) of both the LM and subcutaneous fat were measured, and samples of subcutaneous fat were removed from the 10th- to 12th-rib region for fatty acid analysis. Diet did not affect hot carcass weight (P= 0.15), fat thickness (P= 0.58), LM area (P= 0.57), percentage of internal fat (P= 0.52), yield grade (P= 0.96), marbling (P= 0.73), or quality grade (P= 0.10). However, the LM from steers fed diets formulated with Morex and SM5 barley varieties tended to be lighter (higher L* values, P= 0.08) than the LM from steers fed the corn-based diet. Additionally, fat from steers fed corn tended to be more yellow (higher Hunter b* values, P= 0.09) than fat from steers fed barley-based diets. Although grain source had only minimal effects on the fatty acid composition of subcutaneous fat samples, pentadecanoic acid (15:0) was greater (P< 0.05) in fat from steers fed SM3 and Steptoe barley varieties than in fat from steers fed corn. Stearic acid (18:0) concentrations were higher (P< 0.05) in fat samples from steers fed corn than in those fed the experimental barley lines (SM3 and SM5). Conversely, fat samples from steers fed Steptoe and SM5 barley had greater (P< 0.05) gadoleic acid (20:1) concentrations than fat from steers fed corn or Morex variety. Although the variety/line of barley included in the finishing diet may affect LM and fat color, grain-source (barley vs. corn) had little effect on beef carcass quality and yield grades and did not greatly alter the fatty acid composition of subcutaneous fat.

We present anharmonic vibrational calculations for the Cl-(H2O) cluster and their convergence with the n-mode representation of the interaction potential. Extension of this representation up to 4-mode couplings produces results that appear to be converged to within 10 cm-1or less relative to the exact 6-mode representation for this system. This methodology, in conjunction with the "morphing" technique, which is based on the scaling of the internal coordinates, provides an effective means of fitting intermolecular potentials to measured vibrational spectra. Application of this approach to the chloride-water interaction produces a revision of a previously developed empirical interaction potential that reproduces the measured fundamental and first overtone frequencies to within an average absolute deviation of 1.75 cm-1in the 4-mode coupling representation.

The sorptive behaviour of polycyclic aromatic hydrocarbons (PAHs) is critical to controlling their transport, fates and effects in the environment. Experiments are described which detail the behaviour of a model compound (benzo(a)pyrene) under simulated aquatic conditions. The kinetics of sorption were comparable to those of other PAH compounds. The sorption equilibrium was extensively studied and found to be affected by several key parameters, notably sediment concentration. The sorption coefficient decreased substantially with the sediment concentration, from 9580 ml g−1 at a sediment concentration of 0.067 g l−1 to 1110 ml g−1 at a sediment concentration of 9.8 g l−1. The results are consistent with previous reports and often explained by the presence of colloids. In this paper the dry weight concentration of colloids was determined and used for deriving the true sorption coefficient, which is up to an order of magnitude higher than the observed partition coefficient. The sorption of benzo(a)pyrene was also dependent on some of the particle properties, and the sorption coefficient was found to increase with the organic carbon content and specific surface area of sediment particles. The desorption of benzo(a)pyrene from sediment was shown to be relatively rapid, with implications for the potential remobilisation of benzo(a)pyrene and similar compounds.

ABSTRACTCaspofungin acetate is an antifungal antibiotic that inhibits synthesis of 1,3-β-d-glucan, an essential component of the fungal cell wall. While caspofungin causes cell death in yeasts and dimorphic fungi such as Candida albicans, its effect on Aspergillus fumigatusis less well understood. We used the fluorescent dyes 5,(6)-carboxyfluorescein diacetate (CFDA) and bis-(1,3-dibutylbarbituric acid) trimethine oxonol (DiBAC), which stain live and dead cells, respectively, to further characterize the antifungal activity of caspofungin. For comparison, compounds whose mode of action was either fungistatic (fluconazole, itraconazole) or fungicidal (amphotericin B) were also evaluated. A correlation between caspofungin-induced loss of viability, decreased CFDA staining, and increased DiBAC staining was established first with C. albicans. For A. fumigatus, caspofungin caused similar dye-staining changes, which were quantified by fluorimetric analysis of stained hyphae grown in a medium that promoted dispersed growth. The minimum concentration of caspofungin required to produce these changes also decreased the level of growth-dependent reduction of the indicator dye Alamar Blue. We observed a differential effect of caspofungin as a function of cell position: 88% of apical cells and 61% of subapical branching cells failed to stain with the viable dye CFDA, but only 24% of subapical cells were unstained. Complementary results were seen with germlings from DiBAC-stained, caspofungin-treated cultures. Extended incubation of A. fumigatuswith a single dose of caspofungin affected the same proportion of apical and subapical branching cells for up to 72 h. The dye-staining patterns illustrate that the cells at the active centers for new cell wall synthesis within A. fumigatushyphae are killed when they are exposed to caspofungin.

We report a new full dimensional potential energy surface for the hydronium ion (H3O⁺). This surface is constructed by a least-squares fit of ab initio electronic energies obtained using the CCSD(T) method with an aug-cc-pVTZ basis set, augmented by some calculations using an aug-cc-pVQZ basis set. The calculated inversion barrier is 693 cm^-1. Full dimensional vibrational calculations are reported using the new surface for H3O⁺, D3O⁺, H2DO⁺, and HD2O⁺ using the codes RVIB4 and MULTIMODE. Comparison with all available experimental data on both splittings and vibrational energies shows significant improvement over our previous calculations using the OSS3(p) potential. A number of vibrational band energies and splittings not measured experimentally are reported for D3O⁺, HD2O⁺, and H2DO⁺.

Deacetylation of uridyldiphospho-3-O-(R-hydroxydecanoyl)-N-acetylglucosamine by LpxC is the first committed step in the Pseudomonas aeruginosa biosynthetic pathway to lipid A; homologous enzymes are found widely among Gram-negative bacteria. As an essential enzyme for which no inhibitors have yet been reported, the P. aeruginosa LpxC represents a highly attractive target for a novel antibacterial drug. We synthesized several focused small-molecule libraries, each composed of a variable aromatic ring, one of four heterocyclic/spacer moieties, and a hydroxamic acid and evaluated the LpxC inhibition of these compounds against purified P. aeruginosa enzyme. To ensure that the in vitro assay would be as physiologically relevant as possible, we synthesized a tritiated form of the specific P. aeruginosa glycolipid substrate and measured directly the enzymatically released acetate. Several of our novel compounds, predominantly those having fluorinated substituents on the aromatic ring and an oxazoline as the heterocyclic moiety, demonstrated in vitro IC50 values less than 1 μM. We now report the synthesis and in vitro evaluation of these P. aeruginosa LpxC inhibitors.

ABSTRACTCaspofungin acetate (MK-0991) is an antifungal antibiotic that inhibits the synthesis of 1,3-β-d-glucan, an essential component of the cell wall of several pathogenic fungi. Caspofungin acetate was recently approved for the treatment of invasive aspergillosis in patients who are refractory to or intolerant of other therapies. The activity of 1,3-β-d-glucan synthesis inhibitors against Aspergillus fumigatushas been evaluated in animal models of pulmonary or disseminated disease by using prolongation of survival or reduction in tissue CFU as assay endpoints. Because these methods suffer from limited sensitivity or poor correlation with fungal growth, we have developed a quantitative PCR-based (qPCR) (TaqMan) assay to monitor disease progression and measure drug efficacy. A. fumigatusadded to naı̈ve, uninfected kidneys as either ungerminated conidia or small germlings yielded a linear qPCR response over at least 4 orders of magnitude. In a murine model of disseminated aspergillosis, a burden of A. fumigatuswas detected in each of five different organs at 4 days postinfection by the qPCR assay, and the mean fungal load in these organs was 1.2 to 3.5 log10units greater than mean values determined by CFU measurement. When used to monitor disease progression in infected mice, the qPCR assay detected an increase of nearly 4 log10conidial equivalents/g of kidney between days 1 and 4 following infection, with a peak fungal burden that coincided with the onset of significant mortality. Traditional CFU methodology detected only a marginal increase in fungal load in the same tissues. In contrast, when mice were infected with Candida albicans, which does not form true mycelia in tissues, quantitation of kidney burden by both qPCR and CFU assays was strongly correlated as the infection progressed. Finally, treatment of mice with induced disseminated aspergillosis with either caspofungin or amphotericin B reduced the A. fumigatusburden in infected kidneys to the limit of detection for the qPCR assay. Because of its much larger dynamic range, the qPCR assay is superior to traditional CFU determination for monitoring the progression of disseminated aspergillosis and evaluating the activity of antifungal antibiotics against A. fumigatus.

In contrast to the conservation of floral organ order in angiosperm flowers, nectary glands can be found in various floral and extrafloral positions. Since in Arabidopsis, the nectary develops only at the base of stamens, its specification was assayed with regard to the floral homeotic ABC selector genes. We show that the nectary can form independently of any floral organ identity gene but is restricted to the 'third whorl' domain in the flower. This domain is, in part, specified redundantly by LEAFY and UNUSUAL FLORAL ORGANS. Even though nectary glands arise from cells previously expressing the B class genes, their proper development requires the down-regulation of B class gene activity. While CRABS CLAW is essential for nectary gland formation, its ectopic expression is not sufficient to induce ectopic nectary formation. We show that in Arabidopsis multiple factors act to restrict the nectary to the flower, and surprisingly, some of these factors are LEAFY and UNUSUAL FLORAL ORGANS.

We present a computational method for the calculation of quantum state-to-state reactive probabilities for reduced dimensionality, three degree-of-freedom, AB + CD ↔ A + BCD reactions. Our approach is based on the recently developed wave packet propagation method in real L² eigenstates [Skokov, S.; Bowman, J. M. Phys. Chem. Chem. Phys. 2000, 2, 495]. Here we show how the real L² approach can be used for the calculation of state-to-state probabilities. The “coordinate transformation problem” is relatively easily solved in the L²-eigenstate formulation because the eigenstates used for propagation are analytical functions of the coordinates. The method is tested for the H2 + CN ↔ H + HCN reaction for zero total angular momentum, J, using a previous potential energy surface of Sun and Bowman, who reported reduced dimensionality, time-independent calculations of state-to-state reaction probabilities. New calculations for J > 0 are presented using the adiabatic rotation approximation. In this approximation the L²-eigenstates are obtained efficiently by expanding them in the basis of J = 0 eigenstates. Finally a test of J-shifting is done.

This paper compares several approximate methods for calculating rate coefficients for the O(³P) + HCl reaction to presumably more accurate quantum mechanical calculations that are based on applying the J-shifting approximation (QM/JS) to an accurate cumulative reaction probability for J = 0. All calculations for this work employ the recent S4 potential energy surface, which presents a number of challenges for the approximate methods. The O + HCl reaction also poses a significant challenge to computational dynamics because of the heavy−light−heavy mass combination and the broad noncollinear reaction path. The approximate methods for calculating the thermal rate coefficient that are examined in this article are quasiclassical trajectories (QCT), conventional transition state theory (TST), variational transition state theory employing the improved canonical variational theory (ICVT), ICVT with the microcanonical optimized multidimensional tunneling correction (ICVT/μOMT), and reduced dimensionality quantum mechanical calculations based on adiabatic bend and J-shifting (QM/AB-JS) approximations. It is seen that QCT, TST, and ICVT rate coefficients agree with each other within a factor of 2.7 at 250 K and 1.6 at l000 K, whereas inclusion of tunneling by the ICVT/μOMT, QM/AB-JS, or QM/JS methods increases the rate coefficients considerably. However, the ICVT/μOMT and QM/AB-JS methods yield significantly lower rate coefficients than the QM/JS calculations, especially at lower temperatures. We also report and discuss calculations for the state-selected reaction of O(³P) with HCl in the first excited vibrational state. In addition to the dynamics calculations, we report new electronic structure calculations by the Multi-Coefficient Gaussian-3 (MCG3) method that indicate that one possible source of disagreement between the QM/JS rate coefficients and experiment is that the barrier on the S4 surface may be too narrow.

We investigate rotation-induced Fermi resonances in HOCl by the adiabatic rotation (AR), centrifugal sudden (CS), and exact methods, using a highly accurate potential energy surface [Skokov, S.; Peterson, K. A.; Bowman, J. M. Chem. Phys. Lett. 1999, 312, 494]. We focus on the rotationally mediated interaction between the (2,3,3) and (3,2,0) (vOH,vbend,vOCl) states in the K = 4 subband using exact, AR, and CS methods. A simple two-state model is used to analyze the interaction, and interaction parameters are determined and compared with those of the experiment. A similar analysis is done for the high-energy interacting pair of states (4,0,0) and (3,2,1), using the AR method, and good agreement with the experiment is found. The comparison between AR calculations and the experiment for the metastable (6,0,0) and (4,4,2) states in the K = 0 subband shows good agreement for the value of J where zero-order states cross but not for the coupling constant. We also study rotationally mediated coupling in the pairs of states (1,0,2) and (0,3,2), (1,1,1) and (1,4,1), and (3,0,0) and (2,1,3) using exact and approximate methods. These interactions have not been studied experimentally.

Knotted1-like homeobox (knox) genes are expressed in specific patterns within shoot meristems and play an important role in meristem maintenance. Misexpression of the knox genes, KNAT1 or KNAT2, in Arabidopsis produces a variety of phenotypes, including lobed leaves and ectopic stipules and meristems in the sinus, the region between lobes. We sought to determine the mechanisms that control knox gene expression in the shoot by examining recessive mutants that share phenotypic characteristics with 35S::KNAT1 plants. Double mutants of serrate (se) with either asymmetric1 (as1) or asymmetric2 (as2) showed lobed leaves, ectopic stipules in the sinuses and defects in the timely elongation of sepals, petals and stamens, similar to 35S::KNAT1 plants. Ectopic stipules and in rare cases, ectopic meristems, were detected in the sinuses on plants that were mutant for pickle and either as1 or as2. KNAT1 and KNAT2 were misexpressed in the leaves and flowers of single as1 and as2 mutants and in the sinuses of leaves of the different double mutants, but not in se or pickle single mutants. These results suggest that AS1 and AS2 promote leaf differentiation through repression of knox expression in leaves, and that SE and PKL globally restrict the competence to respond to genes that promote morphogenesis.

Fifty-two Targhee twin-bearing ewes were used in a factorial arrangement of treatments to investigate the role of supplemental vitamin E (vit E); 0 (NE) vs 400 IU of vit E·ew·−1d−1(E) and parainfluenza type 3 (PI3) vaccination; none (NP) vs PI3vaccination (P) in immune function. Parainfluenza type 3 vaccination was used to evoke an immune response. Ewes receiving PI3 were vaccinated at 49 and 21 d before the expected lambing date. Ewes receiving vit E were orally dosed daily, 32 to 0 d before lambing. Blood was collected from ewes at the time of the initial PI3vaccination and 4 h postpartum. Blood was collected from lambs (n = 104) at 3 d postpartum. Ewe and lamb sera were analyzed for anti-PI3antibody titers, immunoglobulin G (IgG) titers, and vit E concentrations. Colostrum was collected 4 h postpartum and analyzed for IgG. The model for ewe and lamb analysis included the main effects of vit E and PI3, sex (lambs model only), and their interactions. No interactions were detected (P> 0.20) for any ewe or lamb variables. Serum anti-PI3titers were greater (P< 0.01) in P ewes and their lambs than NP ewes and their lambs. Serum vit E concentrations were greater (P< 0.01) in E ewes and their lambs than NE ewes and their lambs. Colostral IgG titers and serum anti-PI3titers did not differ (P> 0.20) between E and NE ewes. Serum IgG titers in E ewes and their lambs did not differ (P> 0.15) from IgG titers in NE ewes and their lambs. Lamb anti-PI3titers did not differ (P= 0.76) between lambs reared by E and NE ewes. These results indicate that, although supplemental vit E to the ewe increased lamb serum vit E concentration, it had no effect on measures used in this study to assess humoral immunity in the ewe or passive immunity to the lamb.

We report variational calculations of vibrational energies of CH4, CH3D, CH2D2, CHD3, and CD4 using the code “Multimode” and the ab initio force field of Lee and co-workers [Lee, T. J.; Martin, J. M. L.; Taylor, P. R. J. Chem. Phys. 1995, 102, 254], re-expressed using Morse variables in the stretch displacements. Comparisons are made with experimental energies for CH4 with this potential, and then small adjustments are made to the potential to improve agreement with experiment for CH4. Calculations for the isotopomers are done using the adjusted potential and compared with experiment. Additional vibrational energies and assignments not reported experimentally are also given for CH4 and the isotopomers. Exact rotational−vibrational energies of CH4 are also reported for J = 1.