Immune Responses in Human Necatoriasis: Association between Interleukin-5 Responses and Resistance to Reinfection

Cytokine and proliferative responses to Necator americanus infection were measured in a treatment-reinfection study of infected subjects from an area of Papua New Guinea where N. americanus is highly endemic. Before treatment, most subjects produced detectable interleukin (IL)4 (97%), IL-5 (86%), and interferon (IFN)-γ(64%) in response to adult N. americanus antigen. Pretreatment IFN-γ responses were negatively associated with hookworm burden, decreasing by 18 pg/mL for each increase of 1000 eggs/gram (epg) (n = 75; P < .01). Mean IFN-γ responses increased significantly after anthelmintic treatment, from 166 to 322 pg/mL (n = 42; P < .01). The intensity of reinfection was significantly negatively correlated with pretreatment IL-5 responses, decreasing by 551 epg for each 100 pg/mL increase in production of IL-5 (n = 51; P < .01). These data indicate that there is a mixed cytokine response in necatoriasis, with worm burdenassociated suppression of IFN-γ responses to adult N. americanus antigen. Resistance to reinfection is associated with the parasite-specific IL-5 response

Evaluation of Controlled Release Chromic Oxide Boluses and Alkaline Hydrogen Peroxide Lignin as Markers to Determine Intake of Cows Fed Mature Prairie Hay

A digestion trial involving 8 mature cows fed mature prairie hay ad libitum was conducted to determine the validity of controlled release chromic oxide (Cr) and alkaline hydrogen peroxide lignin (APL) as markers for prediction of forage intake by the fecal output (F0)/indigestibility ratio technique. Seven days after oral administration of Cr boluses, total FO was collected daily, weighed and sampled. Rectal fecal grab samples were collected at 10:00 a.m. each day and at 4-hour intervals on day 4 of collections. Mean fecal Cr output based on total fecal collections was 1,662 mg Cr/day compared to a manufacturer\u27s suggested value of 1,505 mg Cr/day. Based on forage and fecal APL levels, mean fecal APL recovery was 95.9%. Increasing the number of days that grab samples were composited raised R2 values between actual FO and dry matter digestibility (DMD) and those predicted using fecal Cr and APL concentration (R = .56, .70, .77, .79 and .82; .27, .55, -61, .67 and .70 for 1- to 5-day composites for FO and DMD, respectively). With samples composited over the entire 5-day collection period, predicted FO, (DMD) and dry matter intake (DMI) were similar (paired t-test) to actual values. Fecal grab samples and total fecal collection samples, composited over 5 days, provided a similar relationship (R = .71) between actual and predicted DMI. Fecal Cr and APL concentrations were not affected by sampling time of day. Results from this study indicate that grab samples collected once daily and composited over 5 consecutive days can be used to predict FO when controlled release chromic oxide boluses are used. While accuracy of DMD estimations was not as high as that of FO, APL was nearly 100% recoverable and resulted in reliable predictions of DMD and DMI

Effect of Early Weaning on Feedlot Performance and Carcass Characteristics of High Growth Potential Feeder Calves

Steer and heifer calves produced at Ft. Meade were used to evaluate early weaning and accelerated feeding as a management tool when retaining ownership of calves. Calves were weaned at 5 1/2 (EM) or 7 mo (NW) of age and started immediately on a 60% grain feeding program. Slaughter dates represented mean calf ages of 385 or 425 days and days on feed ranged from 179 to 257 days. Range conditions were good and early weaning had little effect on calf weight at any point in the feeding period. Feeding high grain diets to EW calves did not have any detrimental effects on feedlot performance when compared to NW. Early weaned calves produced carcasses that were 5 lb. heavier (P\u3c.05) than carcasses from NW cattle but had no other effects on carcass traits. Days on feed affected marbling scores independently of calf age or weaning group. EW appears to be a useful tool for reducing marketing interval for retained ownership cattle and for improving marbling scores of cattle at young ages

Effects of Amino Acid and Branched-Chain Volatile Fatty Acid Additions on in Vitro Fermentation of Dormant Range Grasses

Two-stage in vitro fermentation was used to screen five amino acids and three branched-chain volatile fatty acids as potential additions to a grain urea supplement for cows grazing dormant winter range. Urea addition alone increased dry matter and fiber digestibility of dormant cool season grasses. Methionine addition improved fiber digestibility and rate of fermentation of cool season grasses over urea alone. Compared to urea addition, the branched-chain volatile fatty acids did not increase dry matter or fiber disappearance or improve rate of fermentation of dormant range grasses. None of the buffer additions tested or urea increased digestibility of the dormant warm season grasses. This preliminary laboratory study indicates that methionine offers the greatest potential for addition to a grain urea supplement to increase utilization of dormant range grasses

International comparison of civilian violent deaths: a public health approach to reduce gun-related deaths in US youth.

OBJECTIVES: The political controversy surrounding firearm fatalities in US youths (aged 15-24 years) continues. This study examines whether a public health approach could reduce gun-related deaths in the US. METHODS: Based on the latest World Health Organization (WHO) data, current (2015) numbers and rates per million of US civilian violent deaths (CVDs) (including transport deaths, suicides and homicides) for both the general population and youths (aged 15-24 years) are examined. US CVD results are considered in a wider context by comparing the results with those of seven other major Western countries (MWCs). To demonstrate the effectiveness of a public health policy, transport deaths between 1979 and 2015 are analysed, which corresponds to a time period when government interventions based on technical improvements and behaviour change were implemented to improve road safety. The statistical significance of the comparison between road fatalities and suicide rates between 1979 and 2015 is determined by the chi-squared test. RESULTS: In 2015, the total number of US CVDs was 101,456, consisting of 44,193 suicides and 17,588 homicides (of which 30,891 were likely to be gun-related deaths). Youth deaths totalled 17,432; 5491 suicides and 4732 homicides, including approximately 5112 gun-related deaths. US CVDs are substantially higher than the other MWCs for both the general population and youths. In 1979, US transport deaths were 57,577, which decreased to 39,675 in 2015. Every country's public health approach to reduce road deaths, when compared with suicides, was highly statistically significant. CONCLUSIONS: Government interventions have reduced transport deaths; thus, new policies may also reduce gun-related violence. The evidence points towards a public health approach, such as that used to reduce road deaths, which could help reduce US firearm-related deaths to levels comparable with other MWCs

Serum d-β-Hydroxybutyrate and Urea Nitrogen as Indicators of Beef Cow Nutritional Status

Mature Simmental x Angus crossbred cows were fed differing levels of nutrition before and after calving (mid-March to early May) to determine if blood serum levels of d-β-hydroxybutyrate (BHB) and urea nitrogen (SUN) could be used as indicators of nutritional status. Visual condition scores and condition score change were used as subjective appraisals of cow nutritional status. BHB levels prior to calving were elevated for cows close to calving and those carrying male fetuses. SUN levels prior to calving were higher for thin cows that were losing body condition. If on a low plane of nutrition after calving, BHB values were higher for fleshier cows in May. No differences for either blood metabolite in May were observed for cows fed higher levels of nutrition after calving. A combination of the two metabolites indicated general changes in nutritional status of beef cows. Large variation among cows of similar condition made these metabolites inconsistent in evaluating small differences in nutritional status

A new dryland development paradigm grounded in empirical analysis of dryland systems science

Global drylands face a host of urgent human and environmental challenges with far-reaching impacts. Improving smallholder agriculture remains a key development pathway to tackle these challenges. The Dryland Development Paradigm (DDP), introduced in 2007, presented a highly influential framework for dryland development based on systems research. This paper empirically derives a new, updated DDP. It assesses recent, cutting-edge dryland science, combining literature review with qualitative and quantitative analysis of research published by the world's largest dryland science and development research initiative. The new DDP comprises eight characteristics that are distilled into three integrative principles: Unpack, Traverse and Share. The new DDP is applied and tested to identify key dryland knowledge and development gaps. A future research agenda is then elucidated, grounded in a research in development approach, in which research anchored in the three integrative principles is embedded within the context it seeks to improve. Supported by greater transdisciplinarity and knowledge co-production, operationalization of the new DDP can deliver both novel scientific insights and development impact in line with the aspirations of the 2030 Sustainable Development Goals

On the complexity of strongly connected components in directed hypergraphs

We study the complexity of some algorithmic problems on directed hypergraphs and their strongly connected components (SCCs). The main contribution is an almost linear time algorithm computing the terminal strongly connected components (i.e. SCCs which do not reach any components but themselves). "Almost linear" here means that the complexity of the algorithm is linear in the size of the hypergraph up to a factor alpha(n), where alpha is the inverse of Ackermann function, and n is the number of vertices. Our motivation to study this problem arises from a recent application of directed hypergraphs to computational tropical geometry. We also discuss the problem of computing all SCCs. We establish a superlinear lower bound on the size of the transitive reduction of the reachability relation in directed hypergraphs, showing that it is combinatorially more complex than in directed graphs. Besides, we prove a linear time reduction from the well-studied problem of finding all minimal sets among a given family to the problem of computing the SCCs. Only subquadratic time algorithms are known for the former problem. These results strongly suggest that the problem of computing the SCCs is harder in directed hypergraphs than in directed graphs.Comment: v1: 32 pages, 7 figures; v2: revised version, 34 pages, 7 figure

Genetic diversity, population structure, and genetic correlation with climatic variation in chickpea (Cicer arietinum) landraces from Pakistan

Chickpea (Cicer arietinum L.) production in arid regions, such as those predominant in Pakistan, faces immense challenges of drought and heat stress. Addressing these challenges is made more difficult by the lack of genetic and phenotypic characterization of available cultivated varieties and breeding materials. Genotyping-by-sequencing offers a rapid and cost-effective means to identify genome-wide nucleotide variation in crop germplasm. When combined with extended crop phenotypes deduced from climatic variation at sites of collection, the data can predict which portions of genetic variation might have roles in climate resilience. Here we use 8113 single nucleotide polymorphism markers to determine genetic variation and compare population structure within a previously uncharacterized collection of 77 landraces and 5 elite cultivars, currently grown in situ on farms throughout the chickpea growing regions of Pakistan. The compiled landraces span a striking aridity gradient into the Thal Desert of the Punjab. Despite low levels of variation across the collection and limited genetic structure, we found some differentiation between accessions from arid, semiarid, irrigated, and coastal areas. In a subset of 232 markers, we found evidence of differentiation along gradients of elevation and isothermality. Our results highlight the utility of exploring large germplasm collections for nucleotide variation associated with environmental extremes, and the use of such data to nominate germplasm accessions with the potential to improve crop drought tolerance and other environmental traits

Inflation and the Scale Dependent Spectral Index: Prospects and Strategies

We consider the running of the spectral index as a probe of both inflation itself, and of the overall evolution of the very early universe. Surveying a collection of simple single field inflationary models, we confirm that the magnitude of the running is relatively consistent, unlike the tensor amplitude, which varies by orders of magnitude. Given this target, we confirm that the running is potentially detectable by future large scale structure or 21 cm observations, but that only the most futuristic measurements can distinguish between these models on the basis of their running. For any specified inflationary scenario, the combination of the running index and unknown post-inflationary expansion history induces a theoretical uncertainty in the predicted value of the spectral index. This effect can easily dominate the statistical uncertainty with which Planck and its successors are expected to measure the spectral index. More positively, upcoming cosmological experiments thus provide an intriguing probe of physics between TeV and GUT scales by constraining the reheating history associated with any specified inflationary model, opening a window into the "primordial dark age" that follows the end of inflation.Comment: 32 pages. v2 and v3 Minor reference updates /clarification