317 research outputs found

    Effects of Organic and Conventional Agricultural Practices on Soil Microbial Communities and Molecular Detection of Soil Borne Disease

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    Agricultural practices affect soil microbial communities and health through the input of pesticides, herbicides, fertilizers, and cycling of crop rotation. By examining the microbial community structure, we analyzed how microbial species respond to the environment that individual farms create. Early detection of soil borne disease is essential for agricultural success. However, monitoring incidence of disease based on plant growth response to pathogenic inoculation may not reveal the amount of pathogenic DNA in soil. A comparative study of tomato production systems was conducted by analysis of soil microbial community structure from four farms in Southeast Georgia for the years 2012 and 2013, and incidence level of disease and plant growth of tomato plants grown in greenhouse soil were measured. The results indicated that the soil fungal, bacterial, and animal communities were unique to each farm (ANOSIM PSclerotiumrolfsii DNA (P=0.0454 and P=0.0278 respectively) in the inoculated than un-inoculated soil measured by quantitative polymerase chain reaction (Q-PCR). Fluorescent in situ hybridization (FISH) was used as an alternative for visual detection of Sclerotium rolfsii through whole cell hybridization. A higher hybridization signal was detected in soil with high Sclerotium DNA (15.55333 pg/µl) than in soil with low Sclerotium DNA (0.0155 pg/µl). In conclusion, this study suggested that farming management practices have an effect on the microbial community structure and chemical components of agricultural soil and that plant growth in a greenhouse setting was not a clear representation of the amount of pathogenic DNA in the soil. Molecular detection of pathogenic DNA in soil could provide important information on predicting the potential for disease development in agricultural ecosystems. Key words: Microbial community structure, Q-PCR, FISH, Sclerotium rolfsii, Soil borne diseas

    Children of Casas Grandes: A Molecular Examination of Subadults at Convento and Paquimé

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    Bioarchaeological research has played a significant role in understanding the Casas Grandes region in northern Mexico. Excavations at the archaeological sites of Convento and Paquimé in Chihuahua, Mexico recovered at least 652 burials dating to AD 700-1450, providing a robust skeletal population for investigations, including research on population demographics, patterns of violence, and social stratification. While there is extensive literature on these individuals, research focusing solely on subadults is nonexistent. This study employs genetic sex-typing using real-time PCR followed by high-resolution melting analysis, as well as strontium isotopic analysis on subadult remains from both Convento and Paquimé to provide estimations of biological sex and migration status. The resulting information is used to address key issues of mobility and social organization. The integration of research of subadults with those of adults is necessary for a better understanding of past societies, and aids particularly in understanding the pre-Hispanic Casas Grandes perception of childhood, violence, and social stratification

    Lumpectomy with or without postoperative radiotherapy for breast cancer with favourable prognostic features: results of a randomized study

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    The aim of this trial was to study the value of adding post-operative radiotherapy to lumpectomy in a subgroup of breast cancer patients with favourable patient-, tumour-, and treatment-related prognostic features. 152 women aged over 40 with unifocal breast cancer seen in preoperative mammography were randomly assigned to lumpectomy alone (no-XRT group) or to lumpectomy followed by radiotherapy to the ipsilateral breast (50 Gy given within 5 weeks, XRT group). All cancers were required to be invasive node-negative, smaller than 2 cm in diameter and well or moderately differentiated, to contain no extensive intraductal component, to be progesterone receptor-positive, DNA diploid, have S-phase fraction ≤7 and be excised with at least 1 cm margin. During a mean follow-up time of 6.7 years, 13 (18.1%) cancers recurred locally in the no-XRT and 6 (7.5%) in the XRT group (P = 0.03). There was no difference between the groups in the ultimate breast preservation rate (95.0% vs. 94.4% in XRT and no-XRT, respectively, P = 0.88), distant metastasis-free survival (P = 0.36), or 5-year cancer-specific survival (97.1% in XRT and 98.6 in no-XRT). Radiation therapy given after lumpectomy reduces the frequency of ipsilateral breast recurrences even in women with small breast cancer with several favourable clinical and biological features. However, the breast preservation rate may not increase due to more frequent use of salvage mastectomies in patients treated with postoperative radiotherapy. © 2001 Cancer Research Campaign http://www.bjcancer.co

    Flourishing in nature: A review of the benefits of connecting with nature and its application as a wellbeing intervention

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    From the increasing number of people living in urban areas to the continued degradation of the natural environment, many of us appear to be physically and psychologically disconnected from nature. We consider the theoretical explanations and present evidence for why this state of affairs might result in suboptimal levels of hedonic and eudaimonic wellbeing by reviewing the large body of research on the mental health benefits of connecting with nature. The advantages of contact with nature as a potential wellbeing intervention are discussed, and examples of how this research is being applied to reconnect individuals to nature and improve wellbeing are given. We conclude by considering the limitations of, and proposing future directions for, research in this area. Overall, evidence suggests that connecting with nature is one path to flourishing in life

    Parasite Dynamics in Untreated Horses Through One Calendar Year

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    Background: Horses are host to a plethora of parasites. Knowledge of the seasonality of parasite egg shedding and transmission is important for constructing parasite control programs. However, studies describing these patterns are sparse, and have largely been conducted only in the United Kingdom. This study evaluated strongylid egg shedding patterns and transmission dynamics of Strongylus vulgaris in naturally infected and untreated mares and foals through one calendar year in Kentucky, USA. The study also investigated the existence of a peri-parturient rise (PPR) in strongylid egg counts in foaling mares and collected information about Strongyloides westeri and Parascaris spp. in the foals. Methods: This study was conducted from January to December 2018. A herd of 18 mares, one stallion, and 14 foals born in 2018 were followed throughout the year. Sera and feces were collected biweekly from all horses, and worm burdens enumerated in 13 foals at necropsy. An S. vulgaris ELISA antibody test was run on all serum samples. Fecal egg counts were determined for all horses, and coproculture and qPCR assay were employed to test for the presence of S. vulgaris in the mature horses. Data were analyzed using the proc glimmix procedure in the SAS 9.4 software program. Results: We found a general lack of seasonality in strongylid egg shedding throughout the year among the mature horses, and no PPR was demonstrated. Shedding of S. vulgaris eggs displayed a higher abundance during the spring, but fndings were variable and not statistically signifcant. Anti-S. vulgaris antibody concentrations did not display signifcant fuctuations in the mature horses, but evidence of passive transfer of antibodies to the foals was demonstrated, and foals assumed their own production of antibodies starting at approximately 20 weeks of age. Overall, colts shed higher numbers of strongylid, ascarid, and S. westeri eggs than fllies. Conclusions: This study demonstrated a lack of seasonality in strongylid egg shedding for the study population, which is in stark contrast to previous studies conducted elsewhere. This strongly suggests that more studies should be done investigating these patterns under diferent climatic condition

    Radiotherapy for early stage favourable breast cancers

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    British Journal of Cancer (2002) 86, 309–310. DOI: 10.1038/sj/bjc/6600004 www.bjcancer.co
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