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991.
Daniel Mengistu Woldeamlak Bewket Rattan Lal 《Land Degradation \u0026amp; Development》2016,27(6):1603-1621
This study analyzes effects of soil and water conservation (SWC) on soil quality and implications to climate change adaptation and mitigation in the Upper Blue Nile River Basin of Ethiopia by using the Anjeni watershed as a case study site. Disturbed and undisturbed soil samples were collected from two sub‐watersheds of Anjeni: the Minchet sub‐watershed (with SWC measures) and the Zikrie sub‐watershed (without SWC measures). Soil samples were taken from 30‐cm depth from five representative landscape positions and analyzed following the standard soil lab analysis procedures. The results show that soils from the conserved sub‐watershed had improved quality indicators compared with those from the non‐conserved site. Significant improvement due to SWC measures was observed in the soil hydrological [total moisture content (+5·43%), field capacity (+5·35%), and available water capacity (+4·18%)] and chemical [cation exchange capacity (+4·40 cmol(+) kg−1), Mg2+ (+1·90 cmol(+) kg−1), Na+ (+0·10 cmol(+) kg−1)] properties. SWC interventions significantly reduced soil erosion by 57–81% and surface runoff by 19–50% in the conserved sub‐watershed. Reduction in soil erosion can maintain the soil organic carbon stock, reduce the land degradation risks, and enhance the C sequestration potential of soils. Therefore, adoption of SWC measures can increase farmers' ability to offset emissions and adapt to climate change. However, SWC measures that are both protective and sufficiently productive have not yet been implemented in the conserved sub‐watershed. Therefore, it is important that SWC structures be supplemented with other biological and agronomic measures in conjunction with soil fertility amendments appropriate to site‐specific conditions. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
992.
Mirdehghan SH Rahemi M Serrano M Guillén F Martínez-Romero D Valero D 《Journal of agricultural and food chemistry》2007,55(3):755-760
Pomegranate fruits were treated with putrescine (Put) or spermidine (Spd) at 1 mM either by pressure infiltration or by immersion and then were stored at 2 degrees C for 60 days. Samples were taken biweekly and were further stored 3 days at 20 degrees C for shelf life study. The treatments were effective on maintaining the concentration of ascorbic acid, total phenolic compounds, and total anthocyanins in arils at higher levels than in control samples. In addition, the two ways of polyamine application increased the levels of total antioxidant activity (TAA) during storage, especially when polyamines were applied by pressure infiltration. Moreover, Spd showed the best results on increasing TAA through maintenance of total phenolic compounds. 相似文献
993.
OBJECTIVES: To assess the occurrence and severity of food insecurity, and examine associations between food insecurity and measures of socio-economic status and indicators of acculturation. DESIGN: Structured interviews among a non-probability sample of West African refugees at baseline and 6 months' follow-up.Setting Mid-sized city in north-eastern USA. SUBJECTS: One hundred and one caregivers with children under the age of 5 years and who have been living the USA for fewer than 4 years. RESULTS: Food insecurity was indicated in approximately half of households (53%). The occurrence of food insecurity was associated with measures of socio-economic status such as income, employment status and participation in the Food Stamp Program (P < 0.05). Measures of acculturation such as difficulty in the shopping environment and language difficulty were also associated with the occurrence and severity of food insecurity, as was time lived in the USA (P < 0.05). Among households who had been in the USA for 1 year or less, food insecurity was indicated in 73%, whereas among households who had been in the USA for at least 3 years food insecurity was indicted in 33%. CONCLUSIONS: Refugees are a potentially vulnerable group and our results echo others in suggesting a need for more thorough monitoring of the health and well-being of recently resettled refugees. These results also suggest that reliance on employment as the sole indicator of success in the resettlement process may be too narrow an indicator. Future research should focus on a wider range of measures of health and well-being. 相似文献
994.
Geographical classification of honey samples by near-infrared spectroscopy: a feasibility study 总被引:3,自引:0,他引:3
Woodcock T Downey G Kelly JD O'Donnell C 《Journal of agricultural and food chemistry》2007,55(22):9128-9134
The potential of near-infrared (NIR) spectroscopy to determine the geographical origin of honey samples was evaluated. In total, 167 unfiltered honey samples (88 Irish, 54 Mexican, and 25 Spanish) and 125 filtered honey samples (25 Irish, 25 Argentinean, 50 Czech, and 25 Hungarian) were collected. Spectra were recorded in transflectance mode. Following preliminary examination by principal component analysis (PCA), modeling methods applied to the spectral data set were partial least-squares (PLS) regression and soft independent modeling of class analogy (SIMCA); various pretreatments were investigated. For unfiltered honey, best SIMCA models gave correct classification rates of 95.5, 94.4, and 96% for the Irish, Mexican, and Spanish samples, respectively; PLS2 discriminant analysis produced a 100% correct classification for each of these honey classes. In the case of filtered honey, best SIMCA models produced correct classification rates of 91.7, 100, 100, and 96% for the Argentinean, Czech, Hungarian, and Irish samples, respectively, using the standard normal variate (SNV) data pretreatment. PLS2 discriminant analysis produced 96, 100, 100, and 100% correct classifications for the Argentinean, Czech, Hungarian, and Irish honey samples, respectively, using a second-derivative data pretreatment. Overall, while both SIMCA and PLS gave encouraging results, better correct classification rates were found using PLS regression. 相似文献
995.
During the past decade, the insect growth regulator pyriproxyfen has been the most used insecticide for controlling the California red scale (CRS), Aonidiella aurantii (Maskell), an important pest in citrus groves worldwide. The aim of the present research was to develop bioassays for determining the effect of pyriproxyfen on developing stages and embryogenesis of CRS that can serve as baselines for monitoring resistance. Pyriproxyfen was very effective against first- and second-instar nymphs of a susceptible strain of CRS; 0.1 and 0.2 mg AI L(-1), resulting in 80 and 100% mortality of first-instar nymphs, and in 62.5 and 91.7% mortality of second-instar nymphs respectively. According to probit analysis, the LC(50) and LC(90) values of pyriproxyfen for first-instar nymphs were 0.03 and 0.15 mg AI L(-1), and for second-instar nymphs they were 0.05 and 0.25 mg AI L(-1) respectively. Pyriproxyfen was quite effective on first-instar nymphs of a CRS field strain originating from a citrus grove where two successive applications of the compound had been applied. Mortality rates were 86 and 100% at concentrations of 0.2 and 0.4 mg AI L(-1) respectively. Pyriproxyfen suppressed embryogenesis when CRS females were treated with pyriproxyfen. Young CRS females treated with 1.0 and 5.0 mg AI L(-1) pyriproxyfen produced 6.6 N(1)/F and 2.4 N(1)/F as compared with 10.9 N(1)/F in untreated control. 相似文献
996.
Breme K Fernandez X Meierhenrich UJ Brevard H Joulain D 《Journal of agricultural and food chemistry》2007,55(5):1932-1938
New, odorant nitrogen- and sulfur-containing compounds are identified in cress extracts. Cress belongs to the botanical order Brassicales and produces glucosinolates, which are important precursors of nitrogen- and sulfur-containing compounds. Those compounds often present low perception thresholds and various olfactive notes and are thus of interest to the flavor and fragrance chemistry. When the study of organonitrogen and organosulfur compounds is undertaken, Brassicale extracts are one of the matrices of choice. Cress extracts were studied by analytical (GC-MS, GC-FPD) and chemical (fractionation) means to identify new interesting odorant compounds. Two compounds that have never been reported in cress extracts, containing both nitrogen and sulfur, were discovered: N-benzyl O-ethyl thiocarbamate and N-phenethyl O-ethyl thiocarbamate. These two molecules being of organoleptic interest, their homologues were synthesized and submitted to organoleptic tests (static and GC-sniffing). Their odors evolve from garlic and onion over green, mushroom- and cress-like to fresh, spearmint-like. This paper presents the origin, chemical synthesis, and organoleptic properties of a series of O-alkyl thiocarbamates. 相似文献
997.
Yang J Ellison S Gogal R Norton H Lindsay DS Andrews F Ward D Witonsky S 《Veterinary parasitology》2006,138(3-4):200-210
Equine protozoal myeloencephalitis (EPM) is one of the most common neurologic diseases of horses in the United States. The primary etiologic agent is Sarcocystis neurona. Currently, there is limited knowledge regarding the protective or pathophysiologic immune response to S. neurona infection or the subsequent development of EPM. The objectives of this study were to determine whether S. neurona infected horses with clinical signs of EPM had altered or suppressed immune responses compared to neurologically normal horses and if blood sample storage would influence these findings. Twenty clinically normal horses and 22 horses with EPM, diagnosed by the presence of S. neurona specific antibodies in the serum and/or cerebrospinal (CSF) and clinical signs, were evaluated for differences in the immune cell subsets and function. Our results demonstrated that naturally infected horses had significantly (P<0.05) higher percentages of CD4 T-lymphocytes and neutrophils (PMN) in separated peripheral blood leukocytes than clinically normal horses. Leukocytes from naturally infected EPM horses had significantly lower proliferation responses, as measured by thymidine incorporation, to a non-antigen specific mitogen than did clinically normal horses (P<0.05). Currently, studies are in progress to determine the role of CD4 T cells in disease and protection against S. neurona in horses, as well as to determine the mechanism associated with suppressed in vitro proliferation responses. Finally, overnight storage of blood samples appears to alter T lymphocyte phenotypes and viability among leukocytes. 相似文献
998.
A 10-year-old, female Newfoundland-cross dog was presented for evaluation of chronic intermittent unilateral epistaxis, nasal stertor, and sneezing. Nasal magnetic resonance imaging revealed a 3 x 5-cm mass in the left nasal cavity. Histopathological evaluation of nasal biopsies determined that the mass was a malignant melanoma. The mass was surgically resected and treated with bilateral opposed photon-beam radiation. This is the first report to describe the presentation, diagnosis, and treatment of an intranasal malignant melanoma in a dog. 相似文献
999.
Weaver KE Rozanski EA Mahony OM Chan DL Freeman LM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(2):234-238
The goals of this study were to compare the efficacy of once-daily administered Glargine insulin to twice-daily administered Lente insulin in cats with diabetes mellitus and to describe the use of a high-protein, low-carbohydrate diet designed for the management of diabetes mellitus in cats. All cats with naturally occurring diabetes mellitus were eligible for inclusion. Baseline testing included a physical examination, serum biochemistry, urinalysis and urine culture, serum thyroxine concentration, and serum fructosamine concentration. All cats were fed the high-protein, low-carbohydrate diet exclusively. Cats were randomized to receive either 0.5 U/kg Lente insulin q12h or 0.5 U/kg Glargine insulin q24h. Re-evaluations were performed on all cats at weeks 1, 2, 4, 8, and 12, and included an assessment of clinical signs, physical examination, 16-hour blood glucose curve, and serum fructosamine concentrations. Thirteen cats completed the study (Lente, n = 7, Glargine, n = 6). There was significant improvement in serum fructosamine and glucose concentrations in all cats but there was no significant difference between the 2 insulin groups. Four of the 13 cats were in complete remission by the end of the study period (Lente, n = 3; Glargine, n = 1). The results of the study support the use of once-daily insulin Glargine or twice-daily Lente insulin in combination with a high-protein, low-carbohydrate diet for treatment of feline diabetes mellitus. 相似文献
1000.