Health risk assessment of Patulin intake through apples and apple-based foods sold in Qatar

This is the first report on assessing the non-carcinogenic health risk associated with Patulin exposure in Qatar. The concentrations of Patulin, as determined in previous studies, in apples, apple juice, and apple-based baby foods sold in Qatar and nearby countries were used to conduct the health risk assessment (HRA). The risk related to Patulin intake by different age groups was calculated using the USEPA risk assessment models. The intake levels (ILs) of various age groups was compared with the international standards. The highest IL in Qatar was for babies between 5-12 months old through ingesting contaminated apple-based baby foods, yet those levels were below the tolerable daily intake of Patulin set by the EU at 0.4 μg/kg BW/d. The results showed that the intake of Patulin in Qatar is lower than that in Tunisia and Iran based on the HRA analysis. The risk caused by chronic exposure to Patulin through ingesting raw apples and apple juice separately was below “1,” indicating that the overall population is not likely to be at risk of Patulin exposure. However, various uncertainties should be considered when adopting these results, mainly the low number of samples and additive exposure to other mycotoxins from different sources.The publication of this article was funded by the Qatar National Library .Scopu

Attenuation of Antagonist-induced Impairment of Dopamine Receptors by L-prolyl - L-leucyl-glycinamide

It has been shown by others that the prenatal treatment of rats with haloperidol, a dopamine D2 receptor antagonist, leads to a permanent reduction in the number of striatal dopamine D2 receptors in adulthood. Conversely, postnatal treatment of lactating dams with haloperidol from birth for 21 days, leads to an increase in the number of striatal dopamine D2 receptors in the litters, when assessed as adults. The present study was undertaken in order to determine whether chronic, long-term postnatal challenge of rat pups per se, with specific dopamine D1 and D2 receptor antagonists, would modify the ontogeny of the respective receptor types. Since the neuropeptide L-prolyl-L-leucyl-glycinamide (PLG) attenuates the effect of haloperidol on dopamine D2 receptors in adult rats, it was of interest to determine whether PLG would modulate antagonist-induced alterations in the ontogeny of striatal dopamine D1 and D2 receptors. Half of the rats were treated daily for 32 days from birth with SCH-23390 (0.30 mg/kg/d i.p.), a selective dopamine D1 antagonist; or spiroperidol (1.0 mg/kg/d i.p.), a selective dopamine D2 antagonist; or both SCH-23390 and spiroperidol; or saline. The other half of the litters were treated with PLG (1.0 mg/kg/d, i.p.), in combination with the other treatments. Animals were decapitated at 5, 8, and 12 weeks from birth for neurochemical analysis of the striatum. Chronic SCH-23390 treatment produced a 70-80% decrease in the binding of (\sp3H) SCH-23390 (300 pM) to striatal homogenates. The alteration at 5 weeks was associated with a 78% decrease in the Bmax for (\sp3H) SCH-23390 binding, and no change in the K\sb{\rm D}. Similarly, at 5, 8, and 12 weeks, chronic spiroperidol treatment reduced the binding of (\sp3H) spiroperidol (300pM) to striatal homogenates by 70-80%. The alteration at 5 weeks was associated with a 74% decrease in the Bmax for (\sp3H) spiroperidol binding, and no change in K\sb{\rm D}. Furthermore, PLG attenuated these respective changes in dopamine D1 and D2 binding, when assessed at 5 and 8 weeks. These findings demonstrate that the postnatal period is a sensitive and critical time in the development of striatal dopamine D1 and D2 receptors and that PLG is able to attenuate the alterations in ontogeny that are produced by dopamine D1 and D2 receptor antagonists

زهير بن أبى سلمى شاعر جاهلى ذو الحكم

Zuhaer bin Abi Sulma adalah salah satu tujuh dari penyair jahili yang terkenal, karya syairnya diabadikan dengan tulisan tinta emas kemudian digantung di tirai penutup dinding Kabah, Zuhaer berbeda dengan penyair jahili yang lain pada zaman jahliyah karena syair-syairnya betul-betul diteliti sebelum diekspressikan ke khalayak ramai, Zuhaer juga terkenal karena kandungan makna syairnya penuh kata hikma

Fine-grained reasoning about the security and usability trade-off in modern security tools

Defense techniques detect or prevent attacks based on their ability to model the attacks. A balance between security and usability should always be established in any kind of defense technique. Attacks that exploit the weak points in security tools are very powerful and thus can go undetected. One source of those weak points in security tools comes when security is compromised for usability reasons, where if a security tool completely secures a system against attacks the whole system will not be usable because of the large false alarms or the very restricted policies it will create, or if the security tool decides not to secure a system against certain attacks, those attacks will simply and easily succeed. The key contribution of this dissertation is that it digs deeply into modern security tools and reasons about the inherent security and usability trade-offs based on identifying the low-level, contributing factors to known issues. This is accomplished by implementing full systems and then testing those systems in realistic scenarios. The thesis that this dissertation tests is that we can reason about security and usability trade-offs in fine-grained ways by building and testing full systems. Furthermore, this dissertation provides practical solutions and suggestions to reach a good balance between security and usability. We study two modern security tools, Dynamic Information Flow Tracking (DIFT) and Antivirus (AV) software, for their importance and wide usage. DIFT is a powerful technique that is used in various aspects of security systems. It works by tagging certain inputs and propagating the tags along with the inputs in the target system. However, current DIFT systems do not track implicit information flow because if all DIFT propagation rules are directly applied in a conservative way, the target system will be full of tagged data (a problem called overtagging) and thus useless because the tags tell us very little about the actual information flow of the system. So, current DIFT systems drop some security for usability. In this dissertation, we reason about the sources of the overtagging problem and provide practical ways to deal with it, while previous approaches have focused on abstract descriptions of the main causes of the problem based on limited experiments. The second security tool we consider in this dissertation is antivirus (AV) software. AV is a very important tool that protects systems against worms and viruses by scanning data against a database of signatures. Despite its importance and wide usage, AV has received little attention from the security research community. In this dissertation, we examine the AV internals and reason about the possibility of creating timing channel attacks against AV software. The attacker could infer information about the AV based only on the scanning time the AV spends to scan benign inputs. The other aspect of AV this dissertation explores is the low-level AV performance impact on systems. Even though the performance overhead of AV is a well known issue, the exact reasons behind this overhead are not well-studied. In this dissertation, we design a methodology that utilizes Event Tracing for Windows technology (ETW), a technology that accounts for all OS events, to reason about AV performance impact from the OS point of view. We show that the main performance impact of the AV on a task is the longer waiting time the task spends waiting on events

The Effect of the Internet Banking on Customer Loyalty: A Study among Malaysian Banks

The banking services have been dynamic during the last decade due to the advent of the Internet in banking sector. One of the most vital challenges of the Internet as a service delivery channel is providing and maintaining service quality. Service quality is an input of customer trust which becomes satisfaction and lead to loyalty as an output. Customer loyalty is a concern of any organizations as well as banking sectors. The purpose of this research was to gain better understanding of the impact of the Internet on customer loyalty in Malaysian banks. Four research questions have been formulated to achieve the purpose. Based on detailed literature review, a frame of reference was developed which helped to answer research questions and guide to data collection. A quantitative research approach was used to get better understanding of this issue. Empirical data were collected through questionnaires with the research questions and the frame of reference. Finally, in the last chapter findings and conclusions were drawn by answering research questions. In the research it was found that all the banks interviewed seem to have the same description, motivation and an underlining objective of customer loyalty and the Internet has affected from two different directions which are made up of both positive and negatives sides on customer loyalty creation by theses banks. The Internet has become more powerful media of providing bank services. Banks use the Internet as a new distribution channel for their products and services. The Internet facilitates home banking services which is becoming more popular in recent time. Another most important finding of this study, from both banks, is service quality which form an integral part of loyalty creation

The effect of illumination compensation methods with histogram back projection for camshift application

This paper presents the results of a factorial experiment performed to determine the effect ofillumination compensation methods with histogram back projection to be used for objecttracking algorithm continuous adaptive mean-shift (Camshift). Since Camshift tracking can beused for distance approximation of an object, a precise tracker algorithm is required. Thisstudy compared two types of illumination compensation methods using Design of Experiment(DOE) in the presence of illumination inconsistency. Based on the results, it was found thatselecting two channels as reference in histogram back projection weakens the accuracy ofCamshift tracking whereas the combination of both methods produces results that are moredesirable.Keywords: object tracking; camshift; vision system; DOE