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101.
Productivity and resource-use efficiency in corn (Zea mays L.) are crucial issues in sustainable agriculture, especially in high-demand resource crops such as corn. The aims of this research were to compare irrigation scheduling and nitrogen fertilization rates in corn, evaluating yield, water (WUE), irrigation water (IRRWUE) and nitrogen use (NUE) efficiencies. A 2-year field experiment was carried out in a Mediterranean coastal area of Central Italy (175 mm of rainfall in the corn-growing period) and corn was subjected to three irrigation levels (rainfed and supply at 50 and 100% of crop evapotranspiration, ETc) in interaction with three nitrogen fertilization levels (not fertilized, 15 and 30 g (N) m−2). The results indicated a large yearly variability, mainly due to a rainfall event at the silking stage in the first year; a significant irrigation effect was observed for all the variables under study, except for plant population. Nitrogen rates affected grain yield plant−1 and ear−1, grain and biomass yield, HI, WUE, IRRWUE and NUE, with significant differences between non-fertilized and the two fertilized treatments (15 and 30 g (N) m−2). Furthermore, deficit irrigation (50% of ETc) was to a large degree equal to 100% of the ETc irrigation regime. A significant interaction “N × I” was observed for grain yield and WUE. The effect of nitrogen availability was amplified at the maximum irrigation water regime. The relationships between grain yield and evapotranspiration showed basal ET, the amount necessary to start producing grain, of about 63 mm in the first and 206 mm in the second year. Rainfed crop depleted most of the water in the 0–0.6 m soil depth range, while irrigated scenarios absorbed soil water within the profile to a depth of 1.0 m. Corn in a Mediterranean area can be cultivated with acceptable yields while saving irrigation water and reducing nitrogen supply and also exploiting the positive interaction between these two factors, so maximizing resource-use efficiency.  相似文献   
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Advocates, practitioners and policy-makers continue to use and advocate for marine protected areas (MPAs) to meet global ocean protection targets. Yet many of the worlds MPAs, and especially no-take MPAs, are plagued by poaching and ineffective governance. Using a global dataset on coral reefs as an example, we quantify the potential ecological gains of governing MPAs to increase compliance, which we call the ‘compliance gap’. Using ecological simulations based on model posteriors of joint Bayesian hierarchical models, we demonstrate how increased compliance in no-take MPAs could nearly double target fish biomass (91% increases in median fish biomass), and result in a 292% higher likelihood of encountering top predators. Achieving these gains and closing the compliance gap necessitates a substantial shift in approach and practice to go beyond optimizing enforcement, and towards governing for compliance. This will require engaging and integrating a broad suite of actors, principles, and practices across three key domains: (i)) harnessing social influence, (ii) integrating equity principles, and (iii) aligning incentives through market-based instruments. Empowering and shaping communication between actor groups (e.g., between fishers, practitioners, and policy-makers) using theoretically underpinned approaches from the behavioural sciences is one of the most essential, but often underserved aspects of governing MPAs. We therefore close by highlighting how this cross-cutting tool could be further integrated in governance to bolster high levels of compliance in MPAs.  相似文献   
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In last years, following the increased canine life expectancy and the rising attention pet-owners devote to their animals, several authors have carried on investigations concerning new techniques to early identify canine prostatic disorders that might affect the dog's quality of life. Prostatic disorders often have an asymptomatic onset and their early diagnosis is difficult: hence, they are usually identified at an advanced stage, only. Traditionally, the diagnosis of prostatic disorders is based on noninvasive tools, such as transrectal and abdominal palpation, seminal or prostatic fluid evaluation, and urinalysis and imaging. On the other hand, a definite diagnosis of prostatic abnormalities could be achieved through prostatic parenchyma Fine Needle Aspiration (FNA) or biopsy. However, these investigations are performed rarely because of their invasiveness. Thus, several authors investigated canine serum biomarkers in order to achieve an earlier diagnostic timing and to apply therapeutic strategies for better outcomes. The Canine Prostatic Specific Esterase (CPSE) has been identified as a suitable biomarker to be included in a prostate health screening program, following the model of prostate-specific antigen (PSA) in human medicine. A higher CPSE in dogs suffering from several prostatic diseases, such as benign prostatic hyperplasia, bacterial prostatitis, or prostatic carcinoma, was reported in literature. Thanks to the potential usefulness in clinical practice, further studies should investigate the potential role of CPSE in monitoring the medical treatment success in the male reproductive system. Moreover, the spreading availability of serum biomarkers, easily carried out on blood samples in clinical practice, could assure a more accurate evaluation of the actual prevalence of prostatic disorders. The CPSE is actually recognized as a promising diagnostic tool for the detection of prostatic disorders in a "prostate health screening program," in order to properly select those patients requiring further more accurate and expensive diagnostic investigations.  相似文献   
104.
The aim of this study was to investigate the effect of initial cooling time at 5°C during semen cryopreservation on post‐thaw quality and reproductive performance of rabbit semen. Pooled semen samples (n = 6) were divided into two subsamples and cooled at 5°C for 45 or 90 min. After cooling, the semen samples were diluted to a ratio of 1:1 (v:v) with a freezing extender composed of Tris‐citrate‐glucose (TCG) containing 16% of dimethylsulfoxide and 0.1 mol/L sucrose. The semen was subsequently loaded in 0.25 ml straws, equilibrated at 5°C and frozen in liquid nitrogen vapor. After thawing, sperm motility, viability, osmotic resistance, acrosome and DNA integrity were assessed. Our results indicate that the longer cooling time, that is, 90 min before cryopreservation significantly improves sperm post‐thaw viability, motility and fertility. In fact, reproductive performances obtained with semen frozen after a 90 min cooling time were similar to those produced by fresh semen insemination. Hence, the present research provides an effective freezing protocol for rabbit semen that will allow for the creation of a sperm cryobank for the conservation of Italian rabbit genetic resources, as well as the use of frozen semen doses in commercial farms.  相似文献   
105.
Both climate and land-use changes, including the introduction and spread of allochthonous species, are forecast to affect forest ecosystems. Accordingly, forests will be affected in terms of species composition as well as their soil chemical and biological characteristics. The possible changes in both tree cover and soil system might impact the amount of carbon that is stored in living plants and dead biomass and within the soil itself. Additionally, such alterations can have a strong impact on ...  相似文献   
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beta-Adrenergic blockers, particularly atenolol, are often recommended for the tachycardia and hypertension that accompany hyperthyroidism; however, the effects of monotherapy with atenolol on both systolic blood pressure (SBP) and heart rate (HR) have not been reported. Twenty hyperthyroid cats with SBP > or = 160 mmHg were studied retrospectively to investigate the SBP and HR lowering effects of atenolol. Median pre-treatment SBP and HR for all cats were 186.5 mmHg and 231 beats/min, respectively. All cats were treated with atenolol at a dosage of 1-2 mg/kg PO q 12h for a minimum of 5 days prior to reassessment and treatment with radioactive iodine. SBP and HR both decreased following atenolol therapy in this group of cats to median values of 171.5 mmHg (P=0.0088) and 185/min (P=0.0003). However, when successful clinical control of hypertension was defined as a post-treatment SBP < 160 mmHg, atenolol monotherapy was ineffective in 70% of the cases. There was no statistically significant difference in baseline serum total thyroxine or atenolol dosage between clinical responders and non-responders. While atenolol effectively reduces HR in most cats with hyperthyroidism, elevated SBP is poorly controlled, and the addition of another vasodilator such as amlodipine or an angiotensin converting enzyme inhibitor is needed to treat associated hypertension.  相似文献   
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