SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Scout Motto

347

There is dogma that higher training load causes higher injury rates. However, there is also evidence that training has a protective effect against injury. For example, team sport athletes who performed more than 18 weeks of training before sustaining their initial injuries were at reduced risk of sustaining a subsequent injury, while high chronic workloads have been shown to decrease the risk of injury. Second, across a wide range of sports, well-developed physical qualities are associated with a reduced risk of injury. Clearly, for athletes to develop the physical capacities required to provide a protective effect against injury, they must be prepared to train hard. Finally, there is also evidence that under-training may increase injury risk. Collectively, these results emphasise that reductions in workloads may not always be the best approach to protect against injury.

Concepts: Injuries, Injury, Protection, Physical trauma, Sport, Knitting, Scout Motto

127

Mental health is a major concern in many countries. We explore whether youth participation in the Scouts and Guides could protect mental health in later life and in particular whether it might reduce inequalities in mental health associated with early life socioeconomic position.

Concepts: Cohort study, Epidemiology, Clinical trial, Sociology, Youth, Baseball, Scout Motto, Scouting

3

Obstetric hemorrhage remains the leading cause of maternal mortality in resource limited areas. An inexpensive pneumatic anti-shock garment was devised of bicycle tubes and tailored cloth which can be prepared from local materials in resource-limited settings. The main purposes of this study were: 1) to determine acceptability of the device by nurses and midwives and obtain suggestions for making the device more suitable for use in their particular work environments, 2) to determine whether a three hour training course provided adequate instruction in the use of this device for the application of circumferential abdominal pelvic pressure, and 3) determine production capability and cost in a resource-limited country.

Concepts: Childbirth, Obstetrics, Maternal death, Proof of concept, Scout Motto, Clothing, Obstetrical hemorrhage

0

Covalently circularized nanodiscs (cNDs) represent a significant advance in the durability and applicability of nanodisc technology. The new cNDs demonstrate higher size homogeneity and improved stability compared with that of non-circularized forms. Moreover, cNDs can be prepared at various defined sizes up to 80-nm diameter. The large cNDs can house much larger membrane proteins and their complexes than was previously possible with the conventional nanodiscs. In order to experience the full advantages of covalent circularization, high quality circularized scaffold protein and nanodisc samples are needed. Here, we give a concise overview and discuss the technical challenges that needed to be overcome in order to obtain high quality preparations. Furthermore, we review some potential new applications for the cNDs.

Concepts: Protein, Atom, Hydrogen bond, Disulfide bond, Membrane protein, Covalent bond, Scout Motto

0

The cyclohexene moiety of the tricyclic 6,7-diaryl-tetrahydro-6H-benzo[c]chromene core of palodesangrens could be assembled in a biomimetic and step-economical fashion by the Diels-Alder reaction between the electron-rich (E)-1,3-butadienylarenes as the diene and the electron-deficient chalcones as the dienophile. During the reduction of ketone to the corresponding alcohol by LiAlH4, the mixture of endo and exo isomers underwent a novel diastereoconvergent LiAlH4-mediated isomerization to install the desired stereochemistry at C10a. Subsequent pyran ring closure under acidic conditions installed the stereochemistry at the remaining C6. Overall, the tricyclic core of palodesangrens could be prepared in 3 steps and up to 38% yield.

Concepts: Alcohol, Amine, Chemical reaction, Alkene, Carbonyl, Ketone, Carboxylic acid, Scout Motto

0

As disasters may occur any time, health care staff and institutions should be prepared to manage these events. The aim of study is to analyze the effects of high-fidelity simulation on the perceptions of senior nursing students regarding their preparedness for disasters.

Concepts: Health care, Health, Nursing, Barack Obama, Scout Motto

0

The [2+2] cycloaddition is a versatile strategy for the synthesis of strained cyclobutenes of high synthetic value. In this study, two efficient intermolecular [2+2] cycloadditions between two different types of chloroalkynes and unactivated alkene are realized with gold catalysis. Of significance is that the reaction works with challenging mono-substituted unac-tivated alkenes, which is unprecedented in gold catalysis and scarcely documented in other metal-catalyzed/promoted reactions; moreover, the reaction exhibits excellent regioselectivities, which are much better than those reported in litera-ture. With 1,2-disubstituted unactivated alkenes, the reaction is largely stereospecific. The cyclobutene products can be prepared in nearly gram scale and readily undergo further reactions including various cross-coupling reactions using the C(sp2)-Cl and/or C(sp2)-SPh bond, which in turn substantially broaden the scope of accessible cyclobutenes and enhance the synthetic utility of this bimolecular reaction.

Concepts: Chemical reaction, Hydrogenation, Alkyne, Alkene, Cycloaddition, Scout Motto

0

Infantile hemangiomas (IHs) of the airway are far less common than their cutaneous counterparts, and their symptoms mimic those of viral croup. As a result, by the time these lesions are diagnosed, they are often advanced and causing airway compromise. Fortunately, the evolution of propranolol as an effective and safe pharmacotherapy has simplified management of IH and reduced the likelihood of complications previously seen with steroid therapy and surgery. Nevertheless, the otolaryngologist must be prepared with an alternate plan to manage lesions refractory to pharmacotherapy. This article reviews the clinical presentation and current management of IHs of the airway.

Concepts: Medicine, Clinical trial, Causality, Greek loanwords, Therapy, Management, Scout Motto, Croup

0

The instability of hydroxyl peroxyesters, the elusive Criegee intermediates of the Bayer-Villiger rearrangement, can be alleviated by selective deactivation of stereoelectronic effects that promote the 1,2-alkyl shift. Stable cyclic Criegee intermediates constrained within a five-membered ring can be prepared by mild reduction of respective hydroperoxyl peroxyesters (β-hydroperoxy-β-peroxylactones) which were formed in high yields in reaction of β-ketoesters with BF3·Et2O/H2O2.

Concepts: Rudolf Criegee, Rearrangement reactions, Scout Motto, Criegee rearrangement

0

Throwing places high demands on the human body, and specific characteristics are developed over time unique to these athletes. When returning to throw after injury, it is important to follow a criterion-based progression that allows the body to be prepared appropriately for the stresses that throwing will require. There is currently a void in the literature for criteria-based progression that helps these athletes return to the highest level of play.

Concepts: Human body, Human anatomy, Returning, Play, Scout Motto, Return statement, Void type