Photocatalytic degradation of metoprolol tartrate in suspensions of two TiO2-based photocatalysts with different surface area. Identification of intermediates and proposal of degradation pathways.

This study investigates the efficiency of the photocatalytic degradation of metoprolol tartrate (MET), a widely used β 1-blocker, in TiO 2 suspensions of Wackherr's " Oxyde de titane standard" and Degussa P25. The study encompasses transformation kinetics and efficiency, identification of intermediates and reaction pathways. In the investigated range of initial concentrations (0.01-0.1mM), the photocatalytic degradation of MET in the first stage of the reaction followed approximately a pseudo-first order kinetics. The TiO 2 Wackherr induced a significantly faster MET degradation compared to TiO 2 Degussa P25 when relatively high substrate concentrations were used. By examining the effect of ethanol as a scavenger of hydroxyl radicals (OH), it was shown that the reaction with OH played the main role in the photocatalytic degradation of MET. After 240min of irradiation the reaction intermediates were almost completely mineralized to CO 2 and H 2O, while the nitrogen was predominantly present as NH4+. Reaction intermediates were studied in detail and a number of them were identified using LC-MS/MS (ESI+), which allowed the proposal of a tentative pathway for the photocatalytic transformation of MET as a function of the TiO 2 specimen

Selective electrochemiluminescent sensing of saccharides using boronic acid-modified coreactant

We report a strategy for modulating the electrogenerated chemiluminescence (ECL) response by integrating a boronic acid to the chemical structure of coreactants. Excellent selectivity for d-glucose was achieved by tuning the linker length of a bis-boronic acid amine coreactant.</p

Chromium content in the meat of male Saanen goat kids from Vojvodina (Northern Serbia)

Goats, the earliest ruminant to be domesticated, are traditional sources of meat, milk, fibre, leather, related products of animal origin and as draught and pack animals. Meat is the major product of the goat. Meat quality is the sum of all sensory, nutritive, technological and hygienic-toxicological factors of meat. The aims of this study were to investigate the chromium content of four different muscles (M. psoas major, M. longissimus dorsi, M. semimembranosus and M. triceps brachii) of Saanen goat male kids and to determine whether the chromium contents differed between the muscles. Chromium content was determined using inductively coupled plasma optical emission spectrometry (ICP-OES), after dry ashing mineralisation. The studied muscles did not significantly differ (P >0.05) with respect to chromium content. The chromium content ranged from 0.012 to 0.067 mg/100 g, with an average of 0.026 mg/100 g

Selective electrochemiluminescent sensing of saccharides using boronic acid-modified coreactant

We report a strategy for modulating the electrogenerated chemiluminescence (ECL) response by integrating a boronic acid to the chemical structure of coreactants.</p

Self-reported symptoms of SARS-CoV-2 infection in a non-hospitalized population : results from the large Italian web-based EPICOVID19 cross-sectional survey. (Preprint)

Background: Understanding the occurrence of Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2)-like symptoms in a large non-hospitalized population, when the epidemic peak was occurring in Italy, is of paramount importance but data are scarce. Objective: Aims of this study were to evaluate the association of self-reported symptoms with SARS-CoV-2 nasopharyngeal swab (NPS) test in non-hospitalized individuals and to estimate the occurrence of COVID-19-like symptoms in a larger non-tested population. Methods: This is an Italian countrywide self-administered cross-sectional web-based survey on voluntary adults who completed an anonymous questionnaire in the period 13-21 April 2020. The associations between symptoms potentially related to SARS-CoV-2 infection and NPS results were calculated as adjusted odds ratios with 95% confidence intervals (aOR, 95%CI) by means of multiple logistic regression analysis controlling for age, sex, education, smoking habits, and the number of co-morbidities. Thereafter, for each symptom and for their combination, we calculated sensitivity, specificity, accuracy and AUC in a ROC analysis to estimate the occurrence of COVID-19-like infections in the non-tested population. Results: A total of 171,310 responded to the survey (59.9% females, mean age 47.4 years). Out of the 4,785 respondents with known NPS test result, 4,392 were not hospitalized. Among them, the NPS positive respondents (n=856) most frequently reported myalgia (61.6%), olfactory and/or taste disorders (OTDs, 59.2%), cough (54.4%), and fever (51.9%) whereas 7.7% were asymptomatic. Multiple regression analysis showed that OTDs (aOR 10.3, [95%CI 8.4-12.7]), fever (2.5, 95%CI 2.0-3.1), myalgia (1.5, 95%CI 1.2-1.8), and cough (1.3, 95%CI 1.0-1.6) were associated with NPS positivity. Having two to four of these symptoms increased the aOR from 7.4 (95%CI, 5.6-9.7) to 35.5 (95%CI, 24.6-52.2). The combination of the four symptoms showed an AUC of 0.810 (95%CI 0.795-0.825) in classifying NPS-P, and was applied to the non-hospitalized and non-tested sample (n=165,782). We found that from 4.4% to 12.1% of respondents had experienced symptoms suggestive of COVID-19 infection. Conclusions: Our results suggest that self-reported symptoms may be reliable indicators of SARS-CoV-2 infection in a pandemic context. A not negligible part (up to 12.1%) of the symptomatic respondents were left undiagnosed and potentially contributed to the spread of the infection

Dynamic Mapping of Electrochemiluminescence Reactivity in Space: Application to Bead-Based Assays

As an electrochemical technique offering an optical readout, electrochemiluminescence (ECL) evolved recently into a powerful microscopy technique with the visualization of a wide range of microscopic entities. However, the dynamic imaging of transient ECL events did not receive intensive attention due to the limited number of electrogenerated photons. Here, the reaction kinetics of the model ECL bioassay system was revealed by dynamic imaging of single [Ru(bpy)(3)](2+)-functionalized beads in the presence of the efficient tripropylamine coreactant. The time profile behavior of ECL emission, the variations of the ECL layer thickness, and the position of maximum ECL intensity over time were investigated, which were not achieved by static imaging in previous studies. Moreover, the dynamics of the ECL emission were confronted with the simulation. The reported dynamic ECL imaging allows the investigation of the ECL kinetics and mechanisms operating in bioassays and cell microscopy

Reading strategies used by TEFL Libyan university students

Reading is a process that requires much effort if students wish to comprehend the text. A large amount of research has been devoted to understanding the processes that contribute to reading comprehension. This research makes a significant contribution to knowledge by exploring the strategies used by Libyan TEFL university students while reading academic materials in class to achieve understanding. It also aims to contribute to knowledge by examining the relationship between level and gender and the use of reading strategies among university students. The study sampled 1st and 4th year male and female students from four Libyan universities. A combination of quantitative and qualitative research methods was utilised to collect data. A 48-item structured questionnaire was administered to 240 students and 12 focus group interviews were conducted with 72 students, in both cases equally balanced in terms of level and gender. SPSS software was utilized to analyse the questionnaire responses while grounded theory was applied to the interview data. Finally, the quantitative and qualitative findings were integrated to provide meaningful conclusions. The quantitative findings revealed different patterns of pre-reading, while-reading and post-reading strategies used by the participants. Some unexpected findings included that, interaction strategies were the least frequently used despite the fact that opportunities to practise the target language outside class were very rare. The qualitative data also provided a number of interesting findings, such as that preparing for the reading task in advance to build up sufficient background and consequently be more confident and relaxed in class, thus revealing a relationship between affective factors and strategy use. Furthermore, the results showed that learners' level had a significant influence on strategy use. 4th year students exhibited superior use of 7 out of 11 strategy types. The qualitative findings supported these conclusions, as even in cases of similar patterns, 4th year students showed more maturity and awareness of strategy use. Statistically significant differences were found favouring female students in the use of most strategies. According to the qualitative findings, female students also reported using more planning and preparing strategies, comprehension strategies, problem- solving strategies and social and supporting strategies. On the other hand, male students reported more use of interpretation strategies. Irrespective of the frequency of use, however, male and female participants expressed different attitudes as to how and why they used various strategies. The findings of the current study draw attention to the influence of other factors such as educational level, class size, and gender balance in class on strategy use, and further studies are needed to explore these issues in more detail and in different contexts. Additionally, the research findings provide empirical information that can be utilized in improving pedagogy in countries where English is taught as a foreign or second language.EThOS - Electronic Theses Online ServiceGBUnited Kingdo