Search results for "substitut"
showing 10 items of 1337 documents
Real Virtuality: A Code of Ethical ConductRecommendations for Good Scientific Practice and the Consumers of VR-Technology
2016
The goal of this article is to present a first list of ethical concerns that may arise from research and personal use of virtual reality (VR) and related technology, and to offer concrete recommendations for minimizing those risks. Many of the recommendations call for focused research initiatives. In the first part of the article, we discuss the relevant evidence from psychology that motivates our concerns. In Section “Plasticity in the Human Mind,” we cover some of the main results suggesting that one’s environment can influence one’s psychological states, as well as recent work on inducing illusions of embodiment. Then, in Section “Illusions of Embodiment and Their Lasting Effect,” we go …
AP5Z1/SPG4 8 frequency in autosomal recessive and sporadic spastic paraplegia
2014
Hereditary spastic paraplegias (HSP) constitute a rare and highly heterogeneous group of neurodegenerative disorders, defined clinically by progressive lower limb spasticity and pyramidal weakness. Autosomal recessive HSP as well as sporadic cases present a significant diagnostic challenge. Mutations in AP5Z1, a gene playing a role in intracellular membrane trafficking, have been recently reported to be associated with spastic paraplegia type 48 (SPG48). Our objective was to determine the relative frequency and clinical relevance of AP5Z1 mutations in a large cohort of 127 HSP patients. We applied a targeted next-generation sequencing approach to analyze all coding exons of the AP5Z1 gene. …
Leptin and Its Receptor are Overexpressed in Brain Tumors and Correlate with the Degree of Malignancy
2009
Although leptin and its receptor (ObR) have emerged as important cancer biomarkers, the role of the leptin system in brain tumor development remains unknown. We screened 87 human brain tumor biopsies using immunohistochemistry and detected leptin and ObR in 55.2% and 60.9% cases, respectively. In contrast, leptin and ObR were absent in 14 samples of normal brain tissue. The presence of leptin correlated with ObR with overall concordance 80.5%. The leptin/ObR system was highly expressed in glioblastomas and anaplastic astrocytomas, while lower expression of both markers was noted in low-grade astrocytomas and gangliogliomas. The association between leptin/ObR and the degree of tumor malignan…
Comparative evaluation of Stevia and Xylitol chewing gum on salivary Streptococcus mutans count ? A pilot study
2020
Background Stevia is a natural sweetener which is used as sugar substitute. It has been suggested that stevia may be anticariogenic. However, there is limited research in this regard. Hence, the present study was designed to assess reduction in S. mutans in stevia and xylitol chewing gums. The aim of this study is to evaluate the effectiveness of stevia and xylitol chewing gums on salivary Streptococcus mutans count. Material and methods A randomized triple blinded clinical study with a crossover design included twenty healthy children aged 8-13 years with decayed, missing, and filled teeth (dmft)/DMFT index score ≥ 3. Before the test, unstimulated saliva was collected. Children divided int…
4-(3H)-quinazolinones N-3 substituted with a five membered heterocycle: A promising scaffold towards bioactive molecules
2020
Abstract The quinazolinone nucleus represents, among the class of fused heterocycles, a very important scaffold to obtain molecules with biological activities. A review of literature revealed how such kind of fused heterocycles, coming from natural or synthetic source, are associated with a wide range of biological activities. This review is mainly directed towards the 4-(3H)-quinazolinones N-3 substituted with a five membered heterocycle in which all the possible combinations of nitrogen, sulfur and oxygen atoms are present.
The apparent losses due to metering errors: a proactive approach to predict losses and schedule maintenance
2014
The effects of water meter age and private tanks on the apparent losses due to metering errors were evaluated by experimental and theoretical analyses. A monitoring campaign on a small district metered area (DMA) was carried out to determine the causes of apparent losses and implement a numerical model. Metering errors are affected by the flow rate passing through the meter, which is dependent on the network pressure and water level of the private tank. A node model that reproduces the effect of private tanks was coupled with EPANET and was applied to the DMA. The proposed modelling approach was used to identify where apparent losses are higher and to schedule maintenance. The model predict…
Modelling Dependencies Between Classifiers in Mobile Masquerader Detection
2004
The unauthorised use of mobile terminals may result in an abuse of sensitive information kept locally on the terminals or accessible over the network. Therefore, there is a need for security means capable of detecting the cases when the legitimate user of the terminal is substituted. The problem of user substitution detection is considered in the paper as a problem of classifying the behaviour of the person interacting with the terminal as originating from the user or someone else. Different aspects of behaviour are analysed by designated one-class classifiers whose classifications are subsequently combined. A modification of majority voting that takes into account some of the dependencies …
When the brain goes diving: glial oxidative metabolism may confer hypoxia tolerance to the seal brain.
2009
Deep diving mammals have developed strategies to cope with limited oxygen availability when submerged. These adaptations are associated with an increased neuronal hypoxia tolerance. Brain neurons of the hooded seal Cysto- phora cristata remain much longer active in hypoxic condi- tions than those of mice. To understand the cellular basis of neuronal hypoxia tolerance, we studied neuroglobin and cy- tochrome c in C. cristata brain. Neuroglobin, a respiratory protein typically found in vertebrate neurons, displays three unique amino acid substitutions in hooded seal. However, these substitutions unlikely contribute to a modulation of O2 affinity. Moreover, there is no significant difference i…
The risk for cardiovascular disease in women: from estrogens to selective estrogen receptor modulators.
2006
Cardiovascular disease, a generic denomination including coronary heart disease (CHD), stroke, and venous thromboembolic disease (VTED), has shown sensitivity to estrogens. The relative protection of women as compared with men has nourished a debate about a possible protective role for estrogens, but the prejudicial effects detected in clinical trials has created confusion on the risk/benefit ratio induced by hormone administration. The hypothesis that agonists distinct to estrogens might improve the effects associated with estrogens is at the base of the increasing interest on the role of selective estrogen receptor modulators (SERMs). There is a lack of definitive clearcut clinical data o…
Selective estrogen receptor modulators and risk for coronary heart disease.
2007
Coronary heart disease (CHD) is the leading cause of death in women in most countries. Atherosclerosis is the main biological process determining CHD. Clinical data support the notion that CHD is sensitive to estrogens, but debate exists concerning the effects of the hormone on atherosclerosis and its complications. Selective estrogen receptor modulators (SERMs) are compounds capable of binding the estrogen receptor to induce a functional profile distinct from estrogens. The possibility that SERMs may shift the estrogenic balance on cardiovascular risk towards a more beneficial profile has generated interest in recent years. There is considerable information on the effects of SERMs on disti…