Root and Top Development of Five Native Kansas Legumes From Seed To End of The First Season

This study was undertaken to obtain more basic information about top and root development during the first season. The plants selected for study were: Petalostemon purpureus (purple prairie clover), Petalostemon candidus (white prairie clover), Psoralea tenuiflora (wild alfalfa), Psoralea cuspidata (prostrate wild alfalfa), and Vicia americana linearis (vetch). Vetch is given as Vicia sparsifolia in Rydberg (1932) but the seeds received were labeled as above and this name was retained. In the following pages it is referred to as Vicia americana for briefness

A farm-level study of risk factors associated with the colonization of broiler flocks with Campylobacter spp. in Iceland, 2001 – 2004

<p>Abstract</p> <p>Background</p> <p>Following increased rates of human campylobacteriosis in the late 1990's, and their apparent association with increased consumption of fresh chicken meat, a longitudinal study was conducted in Iceland to identify the means to decrease the frequency of broiler flock colonization with <it>Campylobacter</it>. Our objective in this study was to identify risk factors for flock colonization acting at the broiler farm level.</p> <p>Methods</p> <p>Between May 2001 and September 2004, pooled caecal samples were obtained from 1,425 flocks at slaughter and cultured for <it>Campylobacter</it>. Due to the strong seasonal variation in flock prevalence, analyses were restricted to a subset of 792 flocks raised during the four summer seasons. Flock results were collapsed to the farm level, such that the number of positive flocks and the total number of flocks raised were summed for each farm. Logistic regression models were fitted to the data using automated and manual selection methods. Variables of interest included manure management, water source and treatment, other poultry/livestock on farm, and farm size and management.</p> <p>Results</p> <p>The 792 flocks raised during the summer seasons originated from 83 houses on 33 farms, and of these, 217 (27.4%) tested positive. The median number of flocks per farm was 14, and the median number of positive flocks per farm was three. Three farms did not have any positive flocks. In general, factors associated with an increased risk of <it>Campylobacter </it>were increasing median flock size on the farm (p ≤ 0.001), spreading manure on the farm (p = 0.004 to 0.035), and increasing the number of broiler houses on the farm (p = 0.008 to 0.038). Protective factors included the use of official (municipal) (p = 0.004 to 0.051) or official treated (p = 0.006 to 0.032) water compared to the use of non-official untreated water, storing manure on the farm (p = 0.025 to 0.029), and the presence of other domestic livestock on the farm (p = 0.004 to 0.028).</p> <p>Conclusion</p> <p>Limiting the average flock size, and limiting the number of houses built on new farms, are interventions that require investigation. Water may play a role in the transmission of <it>Campylobacter</it>, therefore the use of official water, and potentially, treating non-official water may reduce the risk of colonization. Manure management practices deserve further attention.</p

The effects of custodial vs. non-custodial sentences on re-offending: A systematic review of the state of knowledge

As part of a broad initiative of systematic reviews of experimental or quasiexperimental evaluations of interventions in the field of crime prevention and the treatment of offenders, our work consisted in searching through all available databases for evidence concerning the effects of custodial and non-custodial sanctions on reoffending. For this purpose, we examined more than 3,000 abstracts, and finally 23 studies that met the minimal conditions of the Campbell Review, with only 5 studies based on a controlled or a natural experimental design. These studies allowed, all in all, 27 comparisons. Relatively few studies compare recidivism rates for offenders sentenced to jail or prison with those of offenders given some alternative to incarceration (typically probation). According to the findings, the rate of re-offending after a non-custodial sanction is lower than after a custodial sanction in 11 out of 13 significant comparisons. However, in 14 out of 27 comparisons, no significant difference on re-offending between both sanctions is noted. Two out of 27 comparisons are in favour of custodial sanctions. Finally, experimental evaluations and natural experiments yield results that are less favourable to non-custodial sanctions, than are quasi-experimental studies using softer designs. This is confirmed by the meta-analysis including four controlled and one natural experiment. According to the results, non-custodial sanctions are not beneficial in terms of lower rates of re-offending beyond random effects. Contradictory results reported in the literature are likely due to insufficient control of pre-intervention differences between prisoners and those serving “alternative” sanctions

Demography of Australian fur seals (Arctocephalus pusillus doriferus)

© 2009 Dr. John Robert GibbensThe Australian fur seal (Arctocephalus pusillus doriferus) population has displayed a relatively slow rate of recovery since being hunted by commercial sealers during the early 19th century. Despite this, population abundance doubled in the past 2 – 3 decades, indicating that the population growth rate has recently increased. Yet, the factors influencing the population’s dynamics are poorly understood, primarily because basic demographic rates are unknown. Female age, survival, fecundity, breeding and physiology were studied at Kanowna Island, Bass Strait, Australia, between 2003 – 2006 by conducting censuses and captures (n = 294). Mark-recapture estimates of pup production were used to validate direct pup counts, allowing a 9-year dataset to be used for calculation of the population growth rate (2.2% p.a.) and investigation of environmental influences on reproductive success. Annual pup production (x = 3108) was synchronous, with 90% of births occurring within 28 days of the median birth date of 23 November. Births occurred earlier in years when pup production and female body condition were high and these factors were correlated with local oceanographic indicators, suggesting that reproductive success is constrained by environmentally-mediated nutritional stress. Pregnancy was assessed by blood plasma progesterone radioimmunoassay and the pupping status of the same females was observed during breeding season. Despite high mid-gestation pregnancy rates (x = 84%), the birth rate was lower than in other fur seals (x = 53%), suggesting that late-term abortion is common. Lactating females were less likely to pup, indicating that nutrition may be insufficient to support concurrent lactation and gestation. Age and morphometric data were used to construct body growth, age structure and survivorship models. Adult female survival rates were similar to those of other fur seals (x = 88.5%). A life table was constructed and its age-specific survival and fecundity rates used in a Leslie-matrix model to project the population growth rate (2.2% p.a.) and determine the relative influence of each parameter. The abundance of female non-pups was 6 times greater than that of female pups, which is approximately 50% higher than previous conversion factors used to extrapolate population abundance from pup censuses in Australian fur seals. However, if the non-pup sex ratios of other otariids are considered, the pup:population conversion factor is 4.5. Compared to a study performed before the recent population increase, the modern population displays similar body growth and fecundity rates but higher survival rates. This suggests that recent population growth resulted from a relaxation of hunting and/or predation mortality rather than from increased food availability. The low population growth rate is attributed to a low birth rate associated with nutritional stress, yet despite this, body growth occurs rapidly. Such characteristics are typical of sea lions rather than fur seals, perhaps because Australian fur seals employ the typical sea lion strategy of using benthic foraging to exploit a continental shelf habitat. The effect of ecological niche on population dynamics in the Otariidae is discussed

Load tests on five large spread footings on sand and evaluation of prediction methods

Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to [email protected], referencing the URI of the item.Includes bibliographical references.Issued also on microfiche from Lange Micrographics.The design techniques for many of today's modem shallow foundations are often based on figures and formulas developed as many as fifty years ago. These design techniques were developed in the early stages of foundation engineering and are generally conservative and exhibit significant scatter; being based more on intuition and experience than on scientific research. This is not to say that these methods lack merit as they have been utilized in the design of many great engineering projects. For years, the idea of performing full scale load tests on shallow foundations for pure research has not been popular and deep pile foundations have been used more readily in engineering. Today, this lack of full scale load test data is partly responsible for the engineering profession's lack of trust in the use of spread footings. For this study, five spread footings with sizes ranging from I to 3 m square were load tested to 150 mm of penetration. The footings were all constructed and tested in a similar manner at the same general location where the soil consisted of fairly uniform silty fine sand underlain by stiff clay at a depth of 11 m. To the author's knowledge, the testing program described in this work is of a magnitude never before seen for spread footings. A complete summary of the project and its results can be found in Section 6

Remote Sensing Documentation of Historic Rangeland Remediation Treatments in Southern New Mexico

The Jornada Experimental Range and the New Mexico State University Chihuahuan Desert Rangeland Research Center are fruitful areas to study the long-term effects of rangeland remediation treatments which started in the 1930s. A number of diverse manipulations were completed under the direction of federal agency and university scientists, and abundant remote sensing imagery is available to assist in relocating the treatments and evaluating their success. This is particularly important because few of the treatments were maintained following the loss of scientific personnel coinciding with the start of World War II, and most records of Civilian Conservation Corps scientific work were lost with the disbanding of the agency in 1942. Aerial photography, which was systematically used to image the United States beginning in the 1930s, can be used to identify types of treatments, measure areal coverage, estimate longevity, and help plan locations for new experiments. No long-lasting vegetation response could be determined for contour terraces, brush water spreaders, strips grubbed free of shrubs (despite the fact that these strips have remained visible for 65 years), and mechanical rootplowing and seeding. Distinct positive, long-term vegetation responses could be seen in aerial photos for water retention dikes, certain fenced exclosures, and some boundaries where different land management practices meet. It appears from both aerial photos and existing conventional records that experimental manipulation of rangelands has often been ineffective on the landscape scale because treatments are not performed over large enough contiguous areas and hydrological and ecological processes overwhelm the treatments. In addition, treatments are not maintained over time, treatment evaluation periods are sometimes too short, multi-purpose treatments are not used to maximize effects, and treatments are often not located in appropriate sites