Distributed Biomedical Scheme for Controlled Recovery of Medical Encrypted Images

With an advancement in biomedical applications, many images are communicated over the public networks. Therefore, these medical images are prone to various security threats. Development of end to end secure communication protocol for these medical images is found to be a challenging task. Therefore, many researchers have proposed various image medica image encryption techniques to provide end to end security of medical images. However, the existing approaches of block-based recovery of the secret through progressive sharing paradigm have support for limited threshold value of the chosen blocks out of the total number of the blocks during the communication of the image. Most of the suggested scheme has fixed threshold value for the blocks during recovery of secret; works good for a limited threshold (k) value out of number of blocks (n) in which secret has been divided for security. A novel threshold based (any value of k and n) blockwide recovery of secret in progressive secret sharing has been introduced and analyzed for distributed environment. The proposed threshold block wise splitting using progressive visual secret sharing (T-BPVSS) achieves any general higher value of threshold for recovery of secret medical images. Proposed scheme is tested based on various parameters such as varying values of threshold for recovery of secret during enhanced security scenario, as well as changing dimensions of the images and introducing noise in the images. A detailed distributed computing recovery solution is also suggested for the original secret by using distribution technique of shares across the networks of computers. The scheme satisfies for perfect security condition in distributed environment using at least minimum decided threshold numbers of participants (k) before revealing any of the blocks of secret medical image.     

Farmers’ preferences for result-based schemes for grassland conservation in Slovenia

Government-funded payments for ecosystem services (PES) have increasingly been used to facilitate transactions between users of environmental services and their providers. In order to improve the link between payments and the service provided, some countries in the EU have promoted result-based schemes (RBS), which remunerate farmers for ecological results, as part of their agricultural policy. Since PES programs are voluntary, it is important to understand farmers’ responses before more large-scale implementations of RBS are initiated. Using a choice experiment and a mixed logit model, we elicited the preferences of farmers in two Natura 2000 sites in Slovenia for different design elements of a hypothetical scheme for dry grassland conservation. We found that the majority of farmers preferred the result-based approach over the management-based scheme both in terms of payment conditions and monitoring; one group of farmers preferred the RBS very strongly (average WTA of more than 500 EUR/ha/yr) and another group less strongly (average WTA about 200 EUR/ha/yr). Farmers also showed a higher preference for on-farm advise and training in small groups than for lectures, which would be offered to a larger audience. A collective bonus, which would incentivise coordination and could potentially increase participation rates in the scheme, significantly influenced the farmers’ willingness to adopt the scheme. However, the estimated average WTA was comparable or lower than the 40 EUR/ha annual bonus payment. Older farmers and those who managed small and semi-subsistent farms were significantly more likely to be highly resistant to scheme adoption no matter its design.     

Testing bespoke management of foraging habitat for European turtle doves Streptopelia turtur

Agri-environment schemes (AES) are increasingly being employed to mitigate biodiversity loss in agricultural environments. The European Turtle Dove Streptopelia turtur is an obligate granivorous bird in rapid decline within both the UK (−96% since 1970) and across continental Europe (−77% since 1980), despite widespread uptake of AES. Here, we assess the efficacy of a potentially new, sown agri-environment option designed to provide abundant, accessible seed for S. turtur during the breeding season. During summer 2011 we compared vegetation structure and seed provision on trial plots to control habitat types (existing agri-environment options thought to potentially provide S. turtur foraging habitat) to assess whether trial plots performed better for foraging S. turtur than control habitats. In September 2011 all trial plots were topped (cut) and half of a subset of trial plots were then scarified (60% of soil surface disturbed). Vegetation structure on topped, and topped and scarified trial plots was measured during summer 2012 to determine which management regime was most effective in maintaining suitable sward structure and seed provision into the second year. No control habitat type produced as much seed important in S. turtur diet as trial plots at any point during year one. Trial plots provided accessible vegetation structure early in the season with no difference in vegetation metrics between trial plots and previously published data on S. turtur foraging locations. However, to allow later access, management is required during mid-June to open up the sward through localized topping or scarification. Vegetation structure during year two was generally too dense to attract foraging S. turtur. However, scarifying trial plots during the September following sowing encouraged self-seeding of Fumaria. officinalis (a plant species historically forming a significant proportion of S. turtur diet during the breeding season) into the second year, with this species present in 16% of scarified trial plots compared to only 4% of topped trial plots during year two. Thus, autumn scarification, possibly followed by topping or scarification of part of the trial plots in June, is necessary for trial plots to provide more seed and access for S. turtur than existing agri-environment options during year two. We recommend modifications to our original seed mix in order to reduce vegetation density and improve vegetation structure. The study provides an example of the need to strike the right balance between food abundance and accessibility, through vegetation structure, when designing agri-environment scheme management options that provide food for birds.     

Mathematical and numerical analysis for a model of growing metastatic tumors

In cancer diseases, the appearance of metastases is a very pejorative forecast. Chemotherapies are systemic treatments which aim at the elimination of the micrometastases produced by a primitive tumour. The efficiency of chemotherapies closely depends on the protocols of administration. Mathematical modeling is an invaluable tool to help in evaluating the best treatment strategy. Iwata et al. [K. Iwata, K. Kawasaki, N. Shigesad, A dynamical model for the growth and size distribution of multiple metastatic tumors, J. Theor. Biol. 203 (2000) 177.] proposed a partial differential equation (PDE) that describes the metastatic evolution of an untreated tumour. In this article, we conducted a thorough mathematical analysis of this model. Particularly, we provide an explicit formula for the growth rate parameter, as well as a numerical resolution of this PDE. By increasing our understanding of the existing model, this work is crucial for further extension and refinement of the model. It settles down the framework necessary for the consideration of drugs administration effects on tumour development.     

The terminology and use of species–area relationships: a response to Dengler (2009)

Dengler ( Journal of Biogeography , 2009, 36 , 728–744) addresses issues regarding species–area relationships (SARs), but fails to settles those issues. He states that only certain types of sampling schemes should be used to construct SARs, but is not consistent in the criteria that he uses to include some sampling schemes but not others. He argues that a sampling scheme of contiguous plots will be more accurate in extrapolating beyond the sampled area, but logic tells us that a dispersed sampling scheme is likely to be more accurate. Finally, he concludes that the 'true' SAR is a power function, but this conclusion is inconsistent with his results and with the results of others. Rather than defining a narrow framework for SARs, we need to recognize that the relationship between area and species richness is scale- and system-dependent. Different sampling schemes serve different purposes, and a variety of functional relationships are likely to hold. Further theoretical and empirical work is needed to resolve these issues fully.     

CSi2Ga2: a neutral planar tetracoordinate carbon (ptC) building block

Ever being a large curiosity, the “anti-van’t Hoff/Le Bel” realm that is associated with tetracoordinate or hypercoordinate planar centers has made rapid progress. In particular, it has been disclosed that silicon and gallium can be embedded in various planar species. However, to our best knowledge, assembly of silicon— and gallium-embedded planar units has never been reported, though such assembled species might be used as potential nanoscale devices. Here we report the first attempt on how to design assembled molecular compounds featuring silicon— and gallium-embedded planar tetracoordinate carbon (ptC) units. Taking the special silicon- and gallium-embedded ptC unit CSi₂Ga₂ as an example, we performed density functional calculations on a series of model compounds [DM(CSi₂Ga₂)]^q+ as well as the saturated compounds (Cl⁻)_q[CpM(CSi₂Ga₂)]^q+ (D = CSi₂Ga₂, Cp⁻(C₅H₅ ⁻); M = Li, Na, K, Be, Mg, Ca) and the more extended sandwich-like species. For the six metals, CSi₂Ga₂ can only be assembled in the “hetero-decked sandwich” scheme (e.g., [CpM(CSi₂Ga₂)]^q+) so as to avoid cluster fusion. Interestingly, among all the designed sandwich species, CSi₂Ga₂ generally prefers to interact with the partner deck at the corner (Ga atoms) or face (CSi₂Ga₂ planes) sites. Such interaction types serve as an interesting growth pattern that might be applicable to the assembly of Si- and Ga-embedded ptC unit CSi₂Ga₂ into highly extended sandwich-like complexes. Our results for the first time showed that the Si- and Ga-embedded ptC unit CSi₂Ga can act as a new type of building block. The present results are expected to enrich planar tetracoordinate carbon chemistry and metallocenes.     

癌症基因表达谱挖掘中的特征基因选择算法GA/WV

鉴定癌症表达谱的特征基因集合可以促进癌症类型分类的研究,这也可能使病人获得更好的临床诊断?虽然一些方法在基因表达谱分析上取得了成功,但是用基因表达谱数据进行癌症分类研究依然是一个巨大的挑战,其主要原因在于缺少通用而可靠的基因重要性评估方法。GA/WV是一种新的用复杂的生物表达数据评估基因分类重要性的方法,通过联合遗传算法(GA)和加权投票分类算法(WV)得到的特征基因集合不但适用于WV分类器,也适用于其它分类器?将GA/WV方法用癌症基因表达谱数据集的验证,结果表明本方法是一种成功可靠的特征基因选择方法。     

杂交油菜高产栽培多因素组合数学模型的研究

试验采用五因素五水平二次回归正交旋转组合设计,对影响油菜产量的播种期、密度、施氮肥量、施磷肥量和施钾肥量五个可控因子进行了研究,利用微机处理技术建立了油菜产量对五个栽培因子反应的数学模型．研究中运用数学模型优化筛选出油菜不同产量水平的各项栽培因子技术指标,为指导油菜生产、满足不同产量水平的需要,提供一系列切实可行的优化技术方案．通过大面积示范,效果很好．