A new type of chiral sulfonium salts that are characterized by a bicyclic system has been designed and synthesized from α‐amino acids. Their corresponding ylides, which were prepared by basic ...treatment of the sulfonium salts, reacted smoothly with a broad array of simple and chiral aldehydes to provide trans‐epoxy amides in reasonable to very good yields and excellent stereoselectivities (>98 %). The obtained epoxy amides were found to be useful as synthetic building blocks. Thus, they were reduced into their corresponding epoxy alcohols and subjected to oxirane‐ring‐opening reactions with different types of nucleophiles.
Un nuevo tipo de sales de sulfonio quirales, caracterizadas por contener un sistema bicíclico, ha sido diseñado y sintetizado desde α‐amino ácidos. Sus correspondientes iluros, preparados por tratamiento básico de las sales de sulfonio, reaccionaron suavemente con una amplia gama de aldehidos simples y quirales para dar las epoxiamidas trans en rendimientos desde razonables a muy buenos, y estereoselectividad excelente estimada en más de un 98 %. Las epoxiamidas obtenidas probaron ser útiles building blocks. Así, éstas fueron reducidas a sus correspondientes epoxialcoholes y, además, fueron sometidas a reacciones de apertura del anillo de oxirano con diferentes tipos de nucleófilos.
Salty but sweet: Chiral sulfonium salts that featured a bicyclic system reacted with carbonyl compounds to afford epoxy amides with excellent stereoselectivity. A wide array of 1,2‐functionalized systems was prepared by oxirane‐ring‐opening reactions (see scheme).
Currently, Internet of Things (IoT)-based cloud systems face several problems such as privacy leakage, failure in centralized operation, managing IoT devices, and malicious attacks. The data ...transmission between the cloud and healthcare IoT needs trust and secure transmission of Electronic Health Records (EHRs). IoT-enabled healthcare equipment is seen in hospitals that have been implementing the technology for many years. Nonetheless, medical agencies fail to consider the security risk associated with healthcare IoT devices, which are readily compromised and cause potential threats to authentication and encryption procedures. Existing cloud computing methods like homomorphic encryption and the elliptic curve cryptography are unable to meet the security, identity, authentication, and security needs of healthcare IoT devices. The majority of conventional healthcare IoT algorithms lack secure data transmission. Therefore, fog computing is introduced to overcome the problems of IoT device verification, authentication, and identification for scalable and secure transmission of data. In this research manuscript, fog computing includes a hybrid mathematical model: Elliptic Curve Cryptography (ECC) and Proxy Re-encryption (PR) with Enhanced Salp Swarm Algorithm (ESSA) for IoT device verification, identification, and authentication of EHRs. ESSA is incorporated into the PR algorithm to determine the optimal key size and parameters of the PR algorithm. Specifically, in the ESSA, a Whale Optimization Algorithm (WOA) is integrated with the conventional Salp Swarm Algorithm (SSA) to enhance its global and local search processes. The primary objective of the proposed mathematical model is to further secure data sharing in the real time services. The extensive experimental analysis shows that the proposed model approximately reduced 60 Milliseconds (ms) to 18 milliseconds of processing time and improved 25% to 3% of reliability, compared to the traditional cryptographic algorithms. Additionally, the proposed model obtains a communication cost of 4260 bits with a memory usage of 680 bytes in the context of security analysis.
To assess the awareness, knowledge, use, and willingness to use and need of PrEP among men who have sex with men (MSM) and transgender women (TW) who attended World Gay Pride (WGP) 2017 in Madrid.
...Online survey. Participants were recruited through gay-oriented dating apps and HIV Non-Governmental Organizations´ social media. Inclusion criteria included being MSM or TW, age 18 years old or above, and having attended WGP in Madrid. Information regarding the participant's awareness and knowledge, use or willingness to use, and need for PrEP was collected, as well as sociodemographic characteristics. Participants were considered to be in need of PrEP if they met one of the following indication criteria: having practiced unprotected anal intercourse with more than 2 partners, having practiced chemsex, or having engaged in commercial sex-all in the preceding 6 months. Descriptive and multivariable analyses with logistic regression were conducted.
472 participants met the inclusion criteria and completed the questionnaire. The mean age was 38, 97.7% were MSM, 77% had a university education, and 85% were living in Spain, mostly in big cities. Overall, 64% of participants were aware of PrEP, but only 33% knew correctly what PrEP was. 67% of HIV-negative participants were willing to take PrEP, although only 5% were taking it during WGP, mostly due to lack of access. 43% of HIV-negative respondents met at least one PrEP indication criteria. For HIV-negative men living in Spain, university education and living in big cities was associated with PrEP awareness. Lower education level and meeting PrEP criteria was associated with willingness to use PrEP.
Our study shows that among MSM attending WGP 2017 in Madrid, there was limited PrEP awareness, low accuracy of PrEP knowledge, and a high need and willingness to use PrEP. Health authorities should strengthen existing preventive strategies and implement PrEP.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The aim of this study was to determine the psychometric properties of the Alcohol Use Disorders Identification Test (AUDIT and AUDIT-C) in order to detect problems related to the consumption of ...alcohol in the university population. The sample consisted of 1309 students.A Weekly Alcohol Consumption Diary was used as a gold standard; Cronbach's Alpha, the Kappa index, Spearman's correlation coefficient and exploratory factor analysis were applied for diagnostic reliability and validity, with ROC curves used to establish the different cut-off points. Binge Drinking (BD) episodes were found in 3.9% of men and 4.0% of women with otherwise low-risk drinking patterns. AUDIT identified 20.1% as high-risk drinkers and 6.4% as drinkers with physical-psychological problems and probable alcohol dependence.Cronbach's alpha of 0.75 demonstrates good internal consistency. The best cut-off points for high-risk drinking students were 8 for males and 6 for females. As for problem drinkers and probable ADS, 13 was the best cut-off point for both sexes. In relation to AUDIT-C, 5 and 4 were the best cut-off points for males and females with high-risk patterns, respectively. The criterion validity of AUDIT and AUDIT-C to detect binge drinking episodes was found to have a moderate K value. The results obtained show that AUDIT has good psychometric properties to detect early alcohol abuse disorders in university students; however, it is recommended that the cut-off point be reduced to 8 in men. AUDIT-C improves its predictive value by raising the cut-off point by one unit. Items 2 and 3 should be reviewed to increase its predictive value for BD.
Recently, in the context of the Integrated Water Resources Management, demand policies are playing a more important role as opposed to traditional supply policies based on the construction of large ...hydraulic infrastructures. In this new context, water tariffs have become an important tool in achieving economic efficiency, environmental sustainability, and social equity. This paper reviews the situation of urban water tariffs in Spain, a country subject to high water stress. It analyzes the capacity of urban water tariffs to recover service costs and to promote efficiency, sustainability, affordability, and equity. Although it has made significant progress in recent years, the Spanish urban water tariff system still faces many challenges. Many of these challenges would be better addressed by a national independent regulatory body.
There is a need to monitor the growing prevalence of childhood weight issues and obesity worldwide. Parents can establish a set of family rules regarding child behaviors, but parents’ favorable ...attitudes toward healthy nutrition are also necessary. Despite the importance of this issue, there has been very little research on the most efficient means of communication to improve parental intentions to give fruits and vegetables to their children. Social marketing plays a key role in formulating effective communication campaigns targeting parents. We focus on two elements of the communication process, the message endorser and the message framing, and run an experiment with a sample of parents. Results demonstrate that parental intention to provide fruits and vegetables to children will be higher when the related message is backed by an expert endorser (vs. a celebrity endorser), the message is positively framed (vs. negatively framed) and when the message is emotionally framed (vs. rationally framed). Moreover, there is an interaction effect between the influence of the expertise/celebrity characteristic of the endorser and the message framing on parental intention to provide fruits and vegetables, and the effect is higher when the rational message framing is endorsed by an expert.
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•We have produced microcellular aramid films using ionic liquids and ScCO2.•Density has been diminished from 1.4 g cm−3 down to 0.3 g cm3.•Thermal degradation of microcellular aramids ...begins around 400 °C.•Relative Young’s moduli values are higher than 1.2 GPa (g cm−3)−1.
We have deeply diminished the density of high performance aromatic polyamides or aramids. Thus, we have prepared microcellular films that at the same time maintain the outstanding thermal and mechanical properties characteristic of these high performance materials. Two different cellular aramids were produced, based on commercial poly(m-phenylene isophthalamide), one of them with an additional azide group. Microcellular structures have been obtained by adding ionic liquids combined to ScCO2 foaming process, with cell sizes between 0.6 and 4.7 µm and cell densities between 109 and 1011 cells cm3. The density was lowered for the commercial poly(m-phenylene isophthalamide) (Nomex® and Teijin Conex®) from 1.43 to 0.62 g cm−3 and from 1.48 to 0.31 g cm3 for the aramid containing the azide group. Foams present the following thermal and mechanical properties: 5% weight loss observed at T > 400 °C and relative Young modulus and tensile strength of 1.2 GPa (g cm−3)−1 and 60 MPa (g cm−3)−1, respectively.
Networks of social interactions are the substrate upon which civilizations are built. Often, we create new bonds with people that we like or feel that our relationships are damaged through the ...intervention of third parties. Despite their importance and the huge impact that these processes have in our lives, quantitative scientific understanding of them is still in its infancy, mainly due to the difficulty of collecting large datasets of social networks including individual attributes. In this work, we present a thorough study of real social networks of 13 schools, with more than 3,000 students and 60,000 declared positive and negative relationships, including tests for personal traits of all the students. We introduce a metric-the "triadic influence"-that measures the influence of nearest neighbors in the relationships of their contacts. We use neural networks to predict the sign of the relationships in these social networks, extracting the probability that two students are friends or enemies depending on their personal attributes or the triadic influence. We alternatively use a high-dimensional embedding of the network structure to also predict the relationships. Remarkably, using the triadic influence (a simple one-dimensional metric) achieves the best accuracy, and adding the personal traits of the students does not improve the results, suggesting that the triadic influence acts as a proxy for the social compatibility of students. We postulate that the probabilities extracted from the neural networks-functions of the triadic influence and the personalities of the students-control the evolution of real social networks, opening an avenue for the quantitative study of these systems.
The early detection of rotor-casing rub helps to prevent permanent damage or catastrophic failure, saves maintenance costs and decreases the downtime of rotating machines. In aeroderivative gas ...turbines, rub detection is possible only with the use of casing sensors such as accelerometers. In previous works, the Wavelet Synchrosqueezed Transform (WSST) was proposed for very early detection of rub in aeroderivative gas turbines with accelerometer signals. In a quest for even better detection performances, this manuscript aims to design adaptive orthogonal wavelet filter banks for optimal rub feature separation from accelerometer signals. The outputs of the adaptive filter bank show improved feature separation between the no-rub and the rub regimes within a validation set from an experimental machine. Ultimately, it is demonstrated that the combination of the WSST and the adaptive orthogonal filter outperforms other methodologies for the early detection of rotor-casing rub with accelerometer signals, also when white noise is present in the data.
•Adaptive orthogonal wavelet filters improve separation between fault/no fault states.•With those we achieved a more accurate early rub detection within acceleration data.•The filters synthesize the fundamental signal features in a set of coefficients.•Samples from the machine in normal operation and under rub are enough to optimize the filters.
With the increase in global life expectancy and the advance of technology, the creation of age-friendly environments is a priority in the design of new products for elderly people healthcare. This ...paper presents a proposal for a real-time health monitoring system of older adults living in geriatric residences. This system was developed to help caregivers to have a better control in monitoring the health of their patients and have closer communication with their patients' family members. To validate the feasibility and effectiveness of this proposal, a prototype was built, using a biometric bracelet connected to a mobile application, which allows real-time visualization of all the information generated by the sensors (heart rate, body temperature, and blood oxygenation) in the bracelet. Using these data, caregivers can make decisions about the health status of their patients. The evaluation found that the users perceived the system to be easy to learn and use, providing initial evidence that our proposal could improve the quality of the adult's healthcare.
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