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31.
This paper concerns the patterns of food crop choice in a multicropping setting, in which production risk considerations and rainfall uncertainty are likely to be critical factors. The analysis employed plot level panel data from Ethiopia, combined with 30?year meteorological data corresponding to the survey villages used to construct seasonal and yearly rainfall variability. Using the single index approach, the riskiness of crop portfolio was constructed at a household level, taking into account the multicropping nature of the farming system. The combined riskiness of crops grown at a household level responded negatively to annual rainfall variability, with seasonal rainfall variability having a less consistent impact. Farmers are, therefore, more likely to select less risky crop portfolios even when intercrop interactions are taken into account.  相似文献   
32.
Composite Web services (WS) can be seen as software systems designed according to workflow-based orchestration of building blocks or simpler WS. Each block has its own specifications concerning both functional and non-functional properties. While the characteristics of each block have a scope limited to its domain, the WS must guarantee service levels that are usually described by global end-to-end metrics. The problem of relating local to global objectives in WS orchestration is hard to approach. In this context, some WS components have to be deployed in distributed service oriented infrastructure mixing heterogeneous systems belonging to private and/or public providers. In this paper we propose a performance-driven technique for designing and deploying composite WS on heterogeneous service oriented infrastructure. Users having different requirements in terms of resource demands and performance objectives are considered. Several WS deployment alternatives, involving both physical and virtual resources provided by the infrastructure, are evaluated to identify the logical (workflow) and physical (deployment) configuration allowing to meet the requirements. In order to demonstrate the suitability of the proposed approach to the service oriented context, an example of a travel management WS is described and the optimal deployment of the components in a hybrid infrastructure is investigated.  相似文献   
33.
Background: The assessment of human epidermal growth factor receptor 2 (HER2) gene amplification is essential in order to identify those patients affected by advanced gastric cancer who may benefit from Trastuzumab targeted therapy. Materials and Methods: With the aim to investigate the concordance rate in HER2 status between primary gastric carcinoma (GC) and synchronous lymphnode metastases, we investigated HER2 status in a cohort of 108 surgical formalin-fixed paraffin-embedded specimens of GC and matched synchronous metastatic lymph nodes collected from three different units of Anatomic Pathology in southern of Italy. Fleiss-Cohen weighted k statistics were used to assess the concordance rate of HER2 status. Results: HER2 amplification was observed in 17% of primary GCs and the overall concordance rate with corresponding nodal metastases was 90.74%. Changes in HER2 status between primary GC and matched synchronous metastases were evidenced in 10 (9.26%) cases. Of these, 6 cases were HER2 amplified in the primary GC and not amplified in the metastases, while 4 were HER2 not amplified in the primary tumour and amplified in the lymph node metastases. Conclusions: Although at present the simultaneous determination of HER2 in advanced gastric cancer and corresponding metastatic lymph nodes is not mandatory, the possibility that the synchronous metastases of GC have a different HER2 status from that of the primary tumour is of remarkable significance; Indeed this may have influence on the therapeutic management and prognosis of the patients.  相似文献   
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The characteristic aromatic composition of white truffles (Tuber magnatum Pico) determines its culinary and commercial value. However modifications of truffle organoleptic proprieties occur during preservation. A study of headspace of white truffles by using Electronic nose (E-nose), gas chromatography–mass spectrometry (GC–MS) and sensory analyses was performed. Truffles were stored at different conditions for 7 days: +4 and +8 °C wrapped in blotting paper or covered by rice or none of the above. Headspace E-nose measurements and sensory analyses were performed each day. Statistical multivariate analysis of the data showed the capability of E-nose to predict sensorial analysis scores and to monitor aroma profile changes during storage. Truffle’s volatile molecules were also extracted by headspace solid phase microextraction technique and separated and identified by GC–MS. Partial Components Analysis of data was performed. E-nose and GC–MS results were in agreement and showed that truffle storage in paper at +8 °C seemed to be the best storage condition.  相似文献   
36.
A design procedure for high‐order continuous‐time intermediate‐frequency band‐pass filters based on the cascade of low‐Q biquadratic cells is presented. The approach is well suited for integrated‐circuit fabrication, as it takes into account the maximum capacitance spread dictated by the available technology and maximum acceptable sensitivity to component variations. A trade‐off between noise and maximum linear range is also met. A novel, wide‐tuning‐range transconductor topology is also described. Based on these results, a 10‐pole band‐pass filter for a code division multiple‐access satellite receiver has been designed and tested. The filter provides tunable center frequency (f0) from 10 to 70 MHz and exhibits a 28‐MHz bandwidth around f0 = 70 MHz with more than 39‐dB attenuation at f0/2 and 2f0. Third‐order harmonic rejection is higher than 60 dB for a 1‐Vpp 70‐MHz input, and equivalent output noise is lower than 1 mVrms. The circuit is fabricated in a 0.25‐µm complementary metal oxide semiconductor process, and the core consumes 12 mA from a 2.5‐V supply, offering the best current/pole ratio figure. The die area resulted to be 0.9 × 1.1 mm2. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
37.
In this paper we have represented the economic, environmental and territorial transformation of Metaponto district (southern Italy) generated by the land reform since 1950. The coastal area, once inhospitable and unproductive, through land reform has become a point of development for the entire Basilicata Region. The intensive model of economic development applied to agriculture and tourism today represents the main critical points of high environmental impact. In particular, the great human pressure exerted by economic activities has led to an insufficient capacity of water purification systems in the area and such criticism is amplified in the summer mainly for seaside tourism. In this study we have measured the environmental load exerted on the territory and we have estimated the human pressure on the district in the year 2030 and made proposals for amendments to current patterns of development in the agricultural and tourist sectors.  相似文献   
38.
In this article, we reports the effects of the processing conditions on the morphological and hollow attributes of polystyrene micrometric hollow particles produced by the use of a recently developed technique based on the gas foaming of spherical, dense particles. By modulating the foaming temperature and saturation pressure, we produced hollow particles with different attributes in terms of hollow dimensions, eccentricity, and open–close features. The results from these small systems were compared, and we found agreement with what is typically observed in bulk polymeric foaming, for example, an increase in the foaming efficiency with saturation pressure and the nonmonotonic effect of temperature. Furthermore, we observed an increase in the hollow number when using nucleating agents with respect to the neat polymer and when using nitrogen with respect to carbon dioxide as the blowing agent. The effects of particle manipulation before foaming to achieve hollow elongated or distorted particles are also reported. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44236.  相似文献   
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Exposure of the airways epithelium to environmental insults, including cigarette smoke, results in increased oxidative stress due to unbalance between oxidants and antioxidants in favor of oxidants. Oxidative stress is a feature of inflammation and promotes the progression of chronic lung diseases, including Chronic Obstructive Pulmonary Disease (COPD). Increased oxidative stress leads to exhaustion of antioxidant defenses, alterations in autophagy/mitophagy and cell survival regulatory mechanisms, thus promoting cell senescence. All these events are amplified by the increase of inflammation driven by oxidative stress. Several models of bronchial epithelial cells are used to study the molecular mechanisms and the cellular functions altered by cigarette smoke extract (CSE) exposure, and to test the efficacy of molecules with antioxidant properties. This review offers a comprehensive synthesis of human in-vitro and ex-vivo studies published from 2011 to 2021 describing the molecular and cellular mechanisms evoked by CSE exposure in bronchial epithelial cells, the most used experimental models and the mechanisms of action of cellular antioxidants systems as well as natural and synthetic antioxidant compounds.  相似文献   
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