Analysis of Advanced Encryption Standards

The Advanced Encryption Standard (AES),the block cipher ratified as a standard by National Instituteof Standards and Technology of the United States (NIST), waschosen using a process markedly more open and transparentthan its predecessor, the aging Data Encryption Standard(DES).Fifteen algorithm were submitted as to NIST in 1998 ,NIST choose five finalist.NIST primary selection criteria are security, performance,and flexibility. This paper enlightens the last two criteria. Inthis paper we have discussed software performance of five AESfinalist.The paper specifically compares performance of the fiveAES finalist on a verity of common software platform: 32-bitCPU( both large and smaller microprocessors, smart cards,embedded microprocessors) and high end 64-bits CPUs

Diffraction evidence for the structure of cellulose microfibrils in bamboo, a model for grass and cereal celluloses

Background: Cellulose from grasses and cereals makes up much of the potential raw material for biofuel production. It is not clear if cellulose microfibrils from grasses and cereals differ in structure from those of other plants. The structures of the highly oriented cellulose microfibrils in the cell walls of the internodes of the bamboo Pseudosasa amabilis are reported. Strong orientation facilitated the use of a range of scattering techniques. Results: Small-angle neutron scattering provided evidence of extensive aggregation by hydrogen bonding through the hydrophilic edges of the sheets of chains. The microfibrils had a mean centre-to-centre distance of 3.0 nm in the dry state, expanding on hydration. The expansion on hydration suggests that this distance between centres was through the hydrophilic faces of adjacent microfibrils. However in the other direction, perpendicular to the sheets of chains, the mean, disorder-corrected Scherrer dimension from wide-angle X-ray scattering was 3.8 nm. It is possible that this dimension is increased by twinning (crystallographic coalescence) of thinner microfibrils over part of their length, through the hydrophobic faces. The wide-angle scattering data also showed that the microfibrils had a relatively large intersheet d-spacing and small monoclinic angle, features normally considered characteristic of primary-wall cellulose. Conclusions: Bamboo microfibrils have features found in both primary-wall and secondary-wall cellulose, but are crystallographically coalescent to a greater extent than is common in celluloses from other plants. The extensive aggregation and local coalescence of the microfibrils are likely to have parallels in other grass and cereal species and to influence the accessibility of cellulose to degradative enzymes during conversion to liquid biofuel

Recurrent stroke: the role of thrombophilia in a large international pediatric stroke population

Risk factors for arterial ischaemic stroke in children include vasculopathy and prothrombotic risk factors but their relative importance to recurrent stroke is uncertain. Data on recurrent stroke from the databases held in Canada (Toronto), Germany (Kiel-Lubeck/Munster), and UK (London/Southampton) were pooled. Data were available from 894 patients aged 1 month to 18 years at first stroke (median age 6 years) with a median follow-up of 35 months. 160/894 patients (17.9%) had recurrence from 1 day to 136 months after first stroke (median 3.1 months). Among 288 children with vasculopathy, recurrence was significantly more common (hazard ratio (HR) 2.5, 95% confidence intervals (CI) 1.92-3.5) compared to children without vasculopathy. Adjusting for vasculopathy, isolated antithrombin deficiency (HR 3.9; 95%CI 1.4-10.9), isolated elevated lipoprotein (a) (HR 2.3; 95%CI 1.3-4.1), and the presence of more than one prothrombotic risk (HR 1.9; 95%CI 1.12-3.2) were independently associated with an increased risk of recurrence. Recurrence rates calculated per 100 person-years were 10 (95%CI 3-24) for antithrombin deficiency, 6 (95%CI 4-9) for elevated lipoprotein (a), and 13 (95%CI 7-20) for the presence of more than one prothrombotic risk. Identifying children at increased for second stroke events is important in intensifying measures aimed at preventing recurrent stroke

Mortality After Pediatric Arterial Ischemic Stroke

OBJECTIVES: Cerebrovascular disease is among the top 10 causes of death in US children, but risk factors for mortality are poorly understood. Within an international registry, we identify predictors of in-hospital mortality after pediatric arterial ischemic stroke (AIS). METHODS: Neonates (0-28 days) and children (29 days- < 19 years) with AIS were enrolled from January 2003 to July 2014 in a multinational stroke registry. Death during hospitalization and cause of death were ascertained from medical records. Logistic regression was used to analyze associations between risk factors and in-hospital mortality. RESULTS: Fourteen of 915 neonates (1.5%) and 70 of 2273 children (3.1%) died during hospitalization. Of 48 cases with reported causes of death, 31 (64.6%) were strokerelated, with remaining deaths attributed to medical disease. In multivariable analysis, congenital heart disease (odds ratio [OR]: 3.88; 95% confidence interval [CI] : 1.23-12.29; P = .021), posterior plus anterior circulation stroke (OR: 5.36; 95% CI: 1.70-16.85; P = .004), and stroke presentation without seizures (OR: 3.95; 95% CI: 1.26-12.37; P = .019) were associated with in-hospital mortality for neonates. Hispanic ethnicity (OR: 3.12; 95% CI: 1.56-6.24; P = .001), congenital heart disease (OR: 3.14; 95% CI: 1.75-5.61; P < .001), and posterior plus anterior circulation stroke (OR: 2.71; 95% CI: 1.40-5.25; P = .003) were associated with in-hospital mortality for children. CONCLUSIONS: In-hospital mortality occurred in 2.6% of pediatric AIS cases. Most deaths were attributable to stroke. Risk factors for in-hospital mortality included congenital heart disease and posterior plus anterior circulation stroke. Presentation without seizures and Hispanic ethnicity were also associated with mortality for neonates and children, respectively. Awareness and study of risk factors for mortality represent opportunities to increase survival

Structure and structure-property relationship in native cotton : Some challenges to breeders

348-362This paper presents a brief review of the literature on the current status of the supra molecular structure of native cotton fibre and of the experimental data on the physical properties and cellulose crystallite X-ray orientation parameters in respect of a large number of the same cotton varieties, belonging to different species of cotton grown at widely different agroclimatic locations, namely Coimbatore, Nagpur, New Delhi and Sirsa, between 11.00 and 29.00 North latitudes in India. Also presented and discussed are the data on cellulose synthesis in sixteen cotton varieties grown under identical agroclimatic conditions at one location. Possible reasons for the variations in the physical and technological properties of fibres have been observed and the implications of these as challenges to cotton breeders in India are foreseen in the light of the demand of the modern cotton processing technologies.</span

Structure and Strength-Crystallite Orientation Relationship in Native Cotton Fibres

106-119<span style="font-size:11.0pt;line-height:115%; font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family:="" "times="" new="" roman";mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:="" minor-latin;mso-bidi-font-family:"times="" roman";mso-ansi-language:en-us;="" mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">Cotton fibre has a very complex structure at various levels and most of these have not been understood as yet, in spite of considerable efforts put in by innumerable workers, using various physical and allied techniques. Of these, the best efforts have been devoted to understanding the structure of cellulose, which constitutes the bulk of cotton fibre, and the relation between the strength of fibres and the orientation of cellulose crystallites to the fibre axis. In this paper, a review of the most pertinent literature on the structural aspects of cotton fibre is presented; also presented and discussed are data on the physical characteristics and strength-crystallite orientation relationship in respect of a large number of varieties belonging to the Gossypium hirsutum, Gossypium barbadense, Gossypium arboreum and Gossypium herbaceum species of cotton, grown species-wise under identical agroclimatic conditions. This compilation is expected to provide most meaningful comparison of species, varieties and fibre properties and in making a definitive choice about an orientation parameter for varietal characterization of cotton fibres for strength. Such a parameter would be a definitive aid to cotton breeders for a deterministic quality breeding programme and also to cotton fibre technologists for ensuring a uniform quality of finished products. It is concluded from the X-ray diffraction studies on varieties belonging to the four commercial species of cotton that the Hermans crystallite orientation factor is the most reliable index of strength of fibres. Varietal characterization of cotton therefore must be made on the basis of this parameter and not on the basis of 40 or 50% X-ray angles conventionally used.</span

Isothermal PFR/PMR networks

Combinations of Plug Flow Reactor (PFR) and continuous Perfectly Mixed Reactor (PMR, also known as Continuous Stirred Tank Reactor - CSTR) are widely known to give superior performance over a single reactor especially when multiple reactions take place in the reactor. The occurrence of a PMR in an optimal reactor network requires presence of inflection condition in the space of variables describing the reactor objective. The mathematical equation for inflection of multi-dimensional trajectories is derived and applied to five cases of well-known models of kinetic schemes. The previously known results are confirmed or improved upon by applying the technique. A general algorithm for PFR/PMR network synthesis for arbitrary kinetic models is presented