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Electrophilic amination has emerged as a more environmentally benign approach to construct arene C-N bonds. However, heterogeneous catalysts remain largely unexplored in this area, even though their use could facilitate product purification and catalyst recovery. Here we investigate strategies to heterogenize a Cu(2,2'-bipyridine) catalyst for the amination of arenes lacking a directing group with hydroxylamine

ispartof: CHEMCATCHEM vol:15 issue:6 status: published

ispartof: JOURNAL OF CATALYSIS vol:406 pages:206-212 status: published

Background Pediatrics is a specialty reserved until later stages of the medical curriculum, with many students receiving early exposure via volunteering opportunities. Self-perceived confidence across the pediatric curriculum is crucial, due to limited clinical exposure before qualification. We aimed to assess the impact of a 7-week pediatric placement on medical students' self-perceived confidence and factors that influenced self-perceived confidence. Methods We conducted a prospective pilot survey on three cohorts of fifth-year students undertaking pediatric placements in 2018. A two-part questionnaire was distributed before and after the placement, evaluating the level of self-confidence in clinical skills using a 10-point scale. Results Of 103 students, 62 (60%) students completed both questionnaires. Of these, 34 (55%) students reported previous professional experiences with children. There was a significant increase in self-reported confidence scores across ten questions before (mean 5.4 [IQR 4.1-6.1]) and after the placement (7.6 [6.6-8.5], p

Objectives: To review available health and nutrition claims for infant formula products in multiple countries and to evaluate the validity of the evidence used for substantiation of claims. Design: International cross sectional survey. Setting: Public facing and healthcare professional facing company owned or company managed formula industry websites providing information about products marketed for healthy infants delivered at full term in 15 countries: Australia, Canada, Germany, India, Italy, Japan, Nigeria, Norway, Pakistan, Russia, Saudi Arabia, South Africa, Spain, the United Kingdom, and the United States in 2020-22. Main outcome measures: Number and type of claims made for each product and ingredient. References cited were reviewed and risk of bias was assessed for registered clinical trials using the Cochrane risk of bias tool, and for systematic reviews using the Risk Of Bias in Systematic reviews tool., This study received no external funding.

Elastography complements traditional medical imaging modalities by mapping tissue stiffness to identify tumors in the endocrine system, and machine learning models can further improve diagnostic accuracy and reliability. Our objective in this review was to summarize the applications and performance of machine-learning-based elastography on the classification of endocrine tumors. Two authors independently searched electronic databases, including PubMed, Scopus, Web of Science, IEEEXpress, CINAHL, and EMBASE. Eleven (n = 11) articles were eligible for the review, of which eight (n = 8) focused on thyroid tumors and three (n = 3) considered pancreatic tumors. In all thyroid studies, the researchers used shear-wave ultrasound elastography, whereas the pancreas researchers applied strain elastography with endoscopy. Traditional machine learning approaches or the deep feature extractors were used to extract the predetermined features, followed by classifiers. The applied deep learning approaches included the convolutional neural network (CNN) and multilayer perceptron (MLP). Some researchers considered the mixed or sequential training of B-mode and elastographic ultrasound data or fusing data from different image segmentation techniques in machine learning models. All reviewed methods achieved an accuracy of ≥80%, but only three were ≥90% accurate. The most accurate thyroid classification (94.70%) was achieved by applying sequential training CNN; the most accurate pancreas classification (98.26%) was achieved using a CNN–long short-term memory (LSTM) model integrating elastography with B-mode and Doppler images.

A catalyst containing Hf4+ and Zn2+ supported on silica has been found to be highly effective for the synthesis of methylenedianiline (MDA), an indispensable precursor in the polyurethane industry. Its performance was further improved when the silica support was replaced by silica-alumina, which resulted in a catalyst that was both active and selective, as indicated by the high MDA yield and high 4,4′–MDA/(2,2′–MDA + 2,4′–MDA) isomer ratio obtained. Furthermore, the catalyst also gave an appreciable oligomeric MDA (OMDA) yield and was noticeably more stable than the zeolites that were used in comparative tests: it could be used in at least five consecutive runs without any significant loss in activity. The combination of Bronsted and Lewis acidity strongly increases the overall activity and yields a catalyst that represents a remarkably stable and reusable alternative to the commonly studied systems for this reaction.

BACKGROUND The COVID-19 pandemic has potentially had a negative impact on the mental health and well-being of individuals and families. Anxiety levels and risk factors within particular populations are poorly described. OBJECTIVE This study aims to evaluate confidence, understanding, trust, concerns, and levels of anxiety during the COVID-19 pandemic in the general population and assess risk factors for increased anxiety. METHODS We launched a cross-sectional online survey of a large Russian population between April 6 and 15, 2020, using multiple social media platforms. A set of questions targeted confidence, understanding, trust, and concerns in respondents. The State-Trait Anxiety Inventory was used to measure anxiety. Multiple linear regressions were used to model predictors of COVID-19–related anxiety. RESULTS The survey was completed by 23,756 out of 53,966 (44.0% response rate) unique visitors; of which, 21,364 were residing in 62 areas of Russia. State Anxiety Scale (S-Anxiety) scores were higher than Trait Anxiety Scale scores across all regions of Russia (median S-Anxiety score 52, IQR 44-60), exceeding published norms. Time spent following news on COVID-19 was strongly associated with an increased S-Anxiety adjusted for baseline anxiety level. One to two hours spent reading COVID-19 news was associated with a 5.46 (95% CI 5.03-5.90) point difference, 2-3 hours with a 7.06 (95% CI 6.37-7.74) point difference, and more than three hours with an 8.65 (95% CI 7.82-9.47) point difference, all compared to less than 30 minutes per day. Job loss during the pandemic was another important factor associated with higher S-Anxiety scores (3.95, 95% CI 3.31-4.58). Despite survey respondents reporting high confidence in information regarding COVID-19 as well as an understanding of health care guidance, they reported low overall trust in state and local authorities, and perception of country readiness. CONCLUSIONS Among Russian respondents from multiple social media platforms, there was evidence of higher levels of state anxiety associated with recent job loss and increased news consumption, as well as lower than expected trust in government agencies. These findings can help inform the development of key public health messages to help reduce anxiety and raise perceived trust in governmental response to this current national emergency. Using a similar methodology, comparative surveys are ongoing in other national populations.

Surveillance of sleeping posture is essential for bed-ridden patients or individuals at-risk of falling out of bed. Existing sleep posture monitoring and classification systems may not be able to accommodate the covering of a blanket, which represents a barrier to conducting pragmatic studies. The objective of this study was to develop an unobtrusive sleep posture classification that could accommodate the use of a blanket. The system uses an infrared depth camera for data acquisition and a convolutional neural network to classify sleeping postures. We recruited 66 participants (40 men and 26 women) to perform seven major sleeping postures (supine, prone (head left and right), log (left and right) and fetal (left and right)) under four blanket conditions (thick, medium, thin, and no blanket). Data augmentation was conducted by affine transformation and data fusion, generating additional blanket conditions with the original dataset. Coarse-grained (four-posture) and fine-grained (seven-posture) classifiers were trained using two fully connected network layers. For the coarse classification, the log and fetal postures were merged into a side-lying class and the prone class (head left and right) was pooled. The results show a drop of overall F1-score by 8.2% when switching to the fine-grained classifier. In addition, compared to no blanket, a thick blanket reduced the overall F1-scores by 3.5% and 8.9% for the coarse- and fine-grained classifiers, respectively, meanwhile, the lowest performance was seen in classifying the log (right) posture under a thick blanket, with an F1-score of 72.0%. In conclusion, we developed a system that can classify seven types of common sleeping postures under blankets and achieved an F1-score of 88.9%.

A growing number of studies are focusing on the associations between human milk (HM) immunological composition and allergic diseases. This scoping review aims to identify statistical methods applied in the field and highlight pitfalls and unmet needs. A comprehensive literature search in MEDLINE and Embase retrieved 13,607 unique records. Following title/abstract screening, 29 studies met the selection criteria and were included in this review. We found that definitions of colostrum and mature milk varied across the studies. A total of 17 out of 29 (59%) studies collected samples longitudinally, but only 12% of these used serial (longitudinal) analyses. Multivariable analysis was used in 45% of the studies, but statistical approaches to modelling varied largely across the studies. Types of variables included as potential confounding factors differed considerably between models. Discrimination analysis was absent from all studies and only a single study reported classification measures. Outcomes of this scoping review highlight lack of standardization, both in data collection and handling, which remains one of the main challenges in the field. Improved standardization could be obtained by a consensus group of researchers and clinicians that could recommend appropriate methods to be applied in future prospective studies, as well as already existing datasets. © 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open accessarticle distributed under the terms and conditions of the Creative Commons Attribution(CC BY) license (http://creativecommons.org/licenses/by/4.0/).

The present study investigated the significance of auditory discrimination and the use of phonological and orthographic codes during the course of reading development in Chinese students who are deaf or hard of hearing (D/HH). In this study, the reading behaviors of D/HH students in 2 tasks— a task on auditory perception of onset rime and a synonym decision task—were compared with those of their chronological age–matched and reading level (RL)–matched controls. Cross-group comparison of the performances of participants in the task on auditory perception suggests that poor auditory discrimination ability may be a possible cause of reading problems for D/HH students. In addition, results of the synonym decision task reveal that D/HH students with poor reading ability demonstrate a significantly greater preference for orthographic rather than phonological information, when compared with the D/HH students with good reading ability and their RL-matched controls. Implications for future studies and educational planning are discussed.

Fong SSM, Cheung CKY, Ip JY, Chiu JHN, Lam KLH, Tsang WWN. Sport-specific balance ability in Taekwondo practitioners. J. Hum. Sport Exerc. Vol. 7, No. 2, pp. 520-526, 2012. Taekwondo is a combat sport emphasizing on kicking techniques and dynamic footwork. Specialized balance ability is crucial for Taekwondo practitioners. This study aimed to compare (1) the postural stability during turning, and (2) the forward lunge distance between adolescent TKD practitioners and non-practitioners. Nineteen TKD practitioners (12 males, 7 females; Mean age ± SD: 15.58 ± 1.07 years) and nineteen control participants (13 males, 6 females; Mean age ± SD: 16.21 ± 0.98 years) were recruited in the study. Balance performance was assessed by the Forward Lunge Test and Step/Quick Turn Test with the NeuroCom Balance Master system. Forward lunge distance, turn time and turn sway were measured. TKD practitioners were found to turn faster by 35.37% (p=0.004) and sway less during turning by 15.23% (p=0.034) than non-practitioners. The forward lunge distance in TKD practitioners was 5.67% shorter than that in control participants (p=0.046). This study shows that TKD practitioners might have sport-specific balance ability. The findings of this study inspire the exploration of the longitudinal training effect of TKD so as to develop the evidence base for this exercise option to improve the postural control of adolescents with

Prolonged cancer chemotherapy is associated with the development of multidrug resistance (MDR), which is a major cause of treatment failure. Photodynamic therapy (PDT) has been applied as anticancer therapy and a means of circumventing MDR. The antiproliferative effect of pheophorbide a-mediated photodynamic therapy (Pa-PDT) has been demonstrated in several human cancer cell lines, including the uterine sarcoma cell line, MES-SA. This study set out to evaluate, first, the therapeutic potential of Pa-PDT on MES-SA/Dx5 uterine sarcoma cells and, subsequently, the effectiveness of combination therapy using Pa-PDT with doxorubicin (Dox). Our results showed that Pa-PDT was able to circumvent MDR in the P-glycoprotein (P-gp) overexpressing human uterine sarcoma cell line, MES-SA/Dx5. Intracellular accumulation of Pa and Pa-PDT-induced cell death was not abrogated by MDR phenotype, when compared to the parental cell line, MES-SA. Combined therapy using Pa-PDT and Dox, a common chemotherapeutic drug, was found to be synergistic in the cell line, MES-SA/Dx5. Both activity and expression of MDR1 and P-gp were reduced by Pa-PDT treatment and such reductions were attenuated by α-tocopherol, the scavenger of reactive oxygen species (ROS), suggesting that the effect of Pa-PDT was mediated by the generation of intracellular ROS. In conclusion, our findings demonstrated the therapeutic potential of Pa-PDT alone or in combination with Dox in combating multidrug-resistant malignancies.

Pheophorbide a (Pa) has been proposed to be a potential photosensitizer for the photodynamic therapy of human cancer. However, the immunomodulatory effect of Pa, in the absence of irradiation, has not yet been investigated. The present study revealed that Pa possessed immunostimulating effect on a murine macrophages cell line RAW 264.7. Pa could significantly stimulate the growth of RAW 264.7 cells with the maximum effect at 1.0μM after 24, 48 and 72 h of treatment (all p