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Preservation potential of keratin in deep time

Multiple fossil discoveries and taphonomic experiments have established the durability of keratin. The utility and specificity of antibodies to identify keratin peptides has also been established, both in extant feathers under varying treatment conditions, and in feathers from extinct organisms. Here, we show localization of feather-keratin antibodies to control and heat-treated feathers, testifyi

Estimation of HIV incidence and its trend in three key populations in Iran

In Iran, People Who Inject Drugs (PWID), Female Sex Workers (FSW), and prisoners are the main key populations at risk of HIV infection. This study aimed to evaluate the trend of HIV incidence among PWID, FSW and prisoners as an impact measure of HIV harm reduction and prevention efforts in Iran. Data were obtained from the two rounds of national bio-behavioral surveillance surveys among FSW (2010

RIFM fragrance ingredient safety assessment, 1,1-diethoxyheptane, CAS Registry Number 688-82-4

The use of this material under current conditions is supported by existing information. 1,1-Diethoxyheptane was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from the read-across analog octanal dimethyl acetal (CAS # 10022-28-3) show that 1,1-diethoxyheptane

Challenges in high performance big data frameworks

Nowadays, we live in a society with billions of devices that are interconnected and interact together to improve the quality of our lives. The management and processing of information and knowledge have by now become our main resources, and the fundamental factors of economic and social development, and it is achieved through Big Data Frameworks (BDFs). The amount of such data is becoming larger e

Some New Analytic and Computational Results for Operator Riccati Equations

The operator Riccati equation associated with a distributed parameter quadratic cost-linear dynamics control process is considered.Making use of ideas from transport theory, a derivation of a generalized version of the X-Y functions of radiative transfer is given, and it is seen that, under commonly occurring conditions, the new equations may be easier to numerically resolve than the original Ricc

Identifiability conditions for linear systems operating in closed loop

The problem of identifiability of processes using measurements obtained under closed loop operation is treated. Single input-single output systems are considered. It is assumed that the feedback is time invariant, linear and noise free. It is also assumed that no external input signal is injected. Conditions, which are simultaneously necessary and sufficient for identifiability are derived. The re

Tin whiskers: experiments and modelling

Tin whiskers are hair-like single crystals that spontaneously grow from tin-coated surfaces. Whiskers are commonly found in electronic components, where tin coatings are used in, e.g., soldering applications, and to protect components from corrosion. Whiskers are known to cause short-circuits leading to failure of electronic components. The exact mechanisms responsible for whisker formation and gr

A theoretical analysis of recursive identification methods

In this paper five different recursive identification methods will be analyzed and compared, namely recursive versions of the least squares method, the instrumental variable method, the generalized least squares method, the extended least squares method and the maximum likelihood method. They are shown to be similar in structure and need of computer storage and time. Making use of recently develop

Convergence of identification methods based on the instrumental variable approach

A class of identification methods, proposed in [3], are based on the instrumental variable principle. This correspondence contains a continued analysis of convergence of the parameter estimates of these methods. Alternative, sufficient conditions for convergence to correct values are given. It is also shown by construction of counter-examples that the methods do not converge under general conditio

Open source ERP business model framework

ERP systems became popular with large organizations in the 1990s. In the 21st Century, these products were expanded by addition of supply chain management (SCM) and customer relationship management (CRM), as well as access through the Web, creating the ERP II concept. Efforts to increase the market led vendors to serve not only large organizations, but also focus more on small-to-medium sized ente

Convergence properties of the generalised least squares identitication method

Convergence properties of the generalized least squares method are analyzed. The method can be interpreted as optimization of a likelihood function. The number of local maximum points of the likelihood function is examined. It is shown that this number is influenced by the signal to noise ratio. This theoretical result is illustrated by numerical examples using plant measurements. It is also prove

Influence of graphite nanoadditives to vegetable-based oil on machining performance when MQCL assisted hard turning

The current study demonstrates through experiment, the effect of solid lubricant assisted minimum quantity cooling lubrication (MQCL) when turning tempered (~60 HRC) alloyed steel Uddeholm Caldie with cemented carbide tools on the process performance. In MQCL application, nanosized graphite nanoplatelets (GnP) solid lubricant powder was dispersed (0.2% vol.) in rapeseed oil based lubricant “ECOLUB