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91.
The prevalence of osteoporosis and fractures is projected to increase rapidly in the Asia‐Pacific region in coming decades. At the societal level, healthcare providers will face the challenges of paucity of information, lack of awareness among physicians, resource constraints, lack of organization, absence of policies of cost reimbursement, insufficient representation of the problem in curricula and lack of effective, inexpensive and convenient therapy. Poverty, illiteracy, lack of awareness and interest in future quality of life, and co‐morbidities with seemingly greater importance, will all act as challenges at the level of individual patients. Lack of compliance is a function of lack of awareness and motivation, cost, complexity of administration, side‐effects and absence of immediately perceivable benefit. The challenges may be overcome through systematic collection of data, formation or activation of national osteoporosis planning and coordinating groups, development of national guidelines, programs of education of healthcare providers, patients and the general public, adoption of a population‐based prevention strategy, cost‐effective opportunistic screening using clinical decision rules like the osteoporosis self‐assessment tool for Asians, use of the fracture risk assessment tool for therapeutic decision‐making, giving due emphasis to the problem in curricula and development of mechanisms for cost reimbursement. The Asia‐Pacific League of Associations for Rheumatology may take a lead in stimulating, organizing and coordinating these activities.  相似文献   
92.
Papillary thyroid carcinoma (PTC) is the most common endocrine malignancy among other endocrine tumors, and BRAF V600E is a frequent genetic mutation occurring in the disease. Although different molecular techniques, most importantly sequencing has been widely recognized as a gold standard but molecular diagnosis remains an expensive, laborious, and time‐intensive process. Recently, immunohistochemistry (IHC) with anti‐BRAF V600E (VE1) antibody has increased practical utility and implemented clinically for the detection of BRAF V600E mutation. Therefore, the study aimed to evaluate diagnostic accuracy of VE1 IHC for detecting the BRAF V600E mutation frequency and clinical implementation in diagnostic laboratories. In this study, 72 formalin fixed paraffin‐embedded tissues (FFPE) were used to determine the BRAF V600E mutation status using IHC and Sanger sequencing. The mutation was found in 29% and 28% cases using IHC and Sanger sequencing, respectively. Furthermore, the results showed 100% sensitivity, 98.07% specificity, 95.2% positive predictive value, and 100% negative predictive value. Notably, significant associations were found between BRAF V600E status and tumor stage, tumor focality, and extrathyroidal extensions, respectively. VE1 IHC was found to be a highly sensitive, specific, and diagnostically accurate method in this cohort. Therefore, BRAF V600E detection through IHC has been considered as the best tailored technique for routine pathology laboratories.  相似文献   
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Emergency Radiology - Trochlear dysplasia (TD) is a key predisposing risk factor for patellar instability (PI) and lateral patellar dislocation (LPD) injuries. It is useful to understand the...  相似文献   
95.
We present a case of a 71-year-old woman who was incidentally found to have aberrant retropharyngeal internal carotid artery, lying very close to the pharyngeal mucosa, on imaging. Radiologists, otolaryngologists and anaesthetists should be aware of this clinically significant variant which can result in life-threatening bleeding during procedures in the oral cavity or oropharynx.  相似文献   
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BackgroundThough women increasingly make up the majority of medical-school and other science graduates, they remain a minority in academic biomedical settings, where they are less likely to hold leadership positions or be awarded research funding. A major factor is the career breaks that women disproportionately take to see to familial duties. They experience a related, but overlooked, hurdle upon their return: they are often too old to be eligible for ‘early-career researcher’ grants and ‘career-development’ awards, which are stepping stones to leadership positions in many institutions and which determine the demographics of their hierarchies for decades to come. Though age limits are imposed to protect young applicants from more experienced seniors, they have an unintended side effect of excluding returning workers, still disproportionately women, from the running.MethodsIn this joint effort by the European Society of Clinical Microbiology and Infectious Diseases, the Federation of European Microbiological Societies, the Infectious Disease Society of America, the International Society for Infectious Diseases and the Swiss Society for Infectious Diseases, we invited all European Congress of Clinical Microbiology and Infectious Diseases-affiliated medical societies and funding bodies to participate in a survey on current ‘early-career’ application restrictions and measures taken to provide protections for career breaks.RecommendationsThe following simple consensus recommendations are geared to funding bodies, academic societies and other organizations for the fair handling of eligibility for early-career awards: 1. Apply a professional, not physiological, age limit to applicants. 2. State clearly in the award announcement that career breaks will be factored into applicants' evaluations such that: ? Time absent is time extended: for every full-time equivalent of career break taken, the same full-time equivalent will be extended to the professional age limit. ? Opportunity costs will also be taken into account: people who take career breaks risk additional opportunity costs, with work that they did before the career break often being forgotten or poorly documented, particularly in bibliometric accounting. Although there is no standardized metric to measure additional opportunity costs, organizations should (a) keep in mind their existence when judging applicants' submissions, and (b) note clearly in the award announcement that opportunity costs of career breaks are also taken into account. 3. State clearly that further considerations can be undertaken, using more individualized criteria that are specific to the applicant population and the award in question.The working group welcomes feedback so that these recommendations can be improved and updated as needed.  相似文献   
98.
BackgroundChikungunya virus (CHIKV) and dengue virus (DENV) co-circulate in areas endemic with the Aedes mosquito vectors. Both viruses cause similar illnesses which may be difficult to distinguish clinically. CHIKV is also associated with persistent arthralgia.ObjectivesTo compare and describe factors which differentiate between DENV and CHIKV infections on presentation; and to describe predictors of persistent arthralgia in CHIKV patients.Study designPatients aged >14 years diagnosed with acute CHIKV and DENV infections in Kuala Lumpur, Malaysia were retrospectively identified. Clinical and laboratory data were obtained from medical records, and compared. CHIKV patients were telephoned 15–24 months later and interviewed about persistent symptoms. Logistic regression analysis was performed.ResultsA total of 53 CHIKV and 113 DENV patients were included. CHIKV patients were older and more likely to be female. CHIKV was independently associated with arthralgia and rash, while DENV was associated with myalgia, raised aspartate transaminase, and leucopaenia. Forty CHIKV patients were followed up, with a median duration of self-reported arthralgia of 3 months (range, 0–24 months). Eighteen (45%) had persistent arthralgia beyond 4 months, for which age >40 years was an independent predictor. At 1 year, 9 (22.5%) patients had arthralgia.ConclusionIn Kuala Lumpur, selected clinical and laboratory predictors help to distinguish between DENV and CHIKV infections. Persistent arthralgia was a frequent sequel of CHIKV infection in this cohort.  相似文献   
99.
Transition metal carbides (TMCs) have recently emerged as competent members among the family of two-dimensional (2D) materials, owing to their promising applications. There are many promising applications of MXenes; however, their magnetic properties lack a wide margin, both experimentally as well as theoretically, which needs to be investigated for potential use in spintronics. In this study, we carried out a comprehensive etching process via selective extraction of Al layers from Nb2AlC-MAX using a wet electrochemical route under well-optimized conditions to obtain fine 2D-Nb2C MXene sheets. Structural analysis using X-ray diffraction (XRD) confirms the effective removal of Al followed by confirmation of a 2D layered structure from morphological analysis using scanning electron microscopy (SEM). Zero-field-cooled (ZFC) and field-cooled (FC) measurements of MAX and MXene at different field strengths were performed using a superconducting quantum interference device (SQUID). Magnetic measurements reveal the paramagnetic nature of Nb2AlC-MAX measured under 5 mT; however, this changes to a clear superconductor-like diamagnetic behavior with a shift of the magnetization from positive to negative values at low temperatures when measured under 5 mT and 10 mT for Nb2C MXene. The diamagnetism, however, is changed to paramagnetism at 100 mT, which shows the existence of critical fields known typically for a type-II superconductor. To gain an insight into this unusual behavior in MXene, density functional theory (DFT) first-principles calculation was also performed in Wein2K software using spin-polarized generalized gradient approximation (sp-GGA). The magnetic moment of the compound is calculated to be negative, which corresponds well with the experimental finding and suggests that the negative magnetic moment originated from the d-orbital of Nb2C. The present report provides a pathway to deeply understanding the existence of superconductivity-like diamagnetic behavior in Nb2C MXene, which is useful for future magnetic applications.

Transition metal carbides (TMCs) have recently emerged as competent members among the family of two-dimensional (2D) materials, owing to their promising applications.

In two-dimensional (2D) materials, magnetism at the nanoscale is at the forefront of many cutting-edge technological applications, such as spintronic devices. Naguib et al. have synthesized a new class of two-dimensional materials, known as MXenes (MnXn+1), discovered in 2011, giving a possibility of magnetism in such 2D materials and their promising uses in spintronic devices.1 These 2D layer structured early transition metal carbides and/or nitrides are known as MXenes, so named to indicate their structural similarities with graphene.2 MXenes are derived from 3D MAX phases (space group P63/mmc) in which “M” is an early transition metal, e.g., Ti, Ta, V, etc.; “A” is mainly a group 13 or group 14 element (group III-A or IV-A), e.g., Si, Al; “X” is a carbide, nitride or can be both; and n = 1, 2, 3 represents the number of layers, forming 211, 312 and 413 phases.3–5 Over the past decade, this new material has gained enormous attention, thus developing an entirely new research field to disclose the properties of the 2D state of this material. The materials in the 2D regime own a cluster of astonishing physical properties as compared to the 3D nature, but intrinsic two-dimensional magnetism has proved to be challenging. As 2D semiconductors have revamped the field of electronics, similarly, magnetism in 2D materials could remodel spintronic devices that can employ a spin degree of freedom.6,7Nb2C MXene was first synthesized by Naguib et al., but they just reported its electrochemical activity as a promising electrode material.4 Further work has been reported in Nb2C with various biomedical applications, energy storage, supercapacitors, and nanoelectronics.9–19 As far as the magnetism in such 2D MXenes is concerned, it remains less investigated, and this research void needs to be filled. Recently, Babar et al. reported the observation of superconductivity in as-prepared powdered Nb2C for the first time, with the highest onset transition temperature Tc,onset = 12.5 K among the MXene family. However, the authors did not discuss the magnetic nature of the parent Nb2AlC MAX itself and did not reason for the presence of unusual magnetic effects in MXene.8 MXenes are favorable members of 2D magnetism, and different magnetic natures are computationally predicted in various carbide and nitride MXenes.7,20 The existence of novel room-temperature ferromagnetic order in doped MXene and the coexistence of different magnetic phases in MXene, along with experimental evidence, indicate its potential of hosting diverse magnetic natures.21,22 Considerable research has been focused on these 2D structures due to their importance and favorable applications, such as spintronics. MXene could provide a vast platform for exploring the magnetic properties and is one of the best candidates that can host superconductivity as compared to other members of the 2D family. Experimental studies are generally dependent upon numerous variables, thus affecting the research pace. However, density functional theory-based first principles calculation and theoretical simulations are a successful way to examine and foresee the properties of low-dimensional materials. This provoked us to theoretically explore superconductivity in Nb2C and their validation through superconductivity measurements of experimentally synthesized Nb2C MXene. In this work, we report a systematic etching mechanism of Nb2C MXene to obtain fine 2D sheets via a chemical etching route using hydrofluoric (HF) acid. Structural and morphological studies using the X-ray diffraction technique (XRD), scanning electron microscopy (SEM) and elemental analysis by energy-dispersive X-ray spectroscopy (EDX) show the effective removal of Al from the parent 3D-Nb2AlC MAX, thus revealing an accordion-like sheet structure. Optical analysis indicates a significant reduction in bandgap after chemical etching. Magnetic properties were carried out to observe the signatures of superconductivity (a perfect diamagnetic state, negative magnetic moment) and its magnetic nature at room temperature. To study the magnetic nature of as-prepared powder-form Nb2C, density functional theory (DFT) first principles calculation was carried out through Wein2K using spin-polarized generalized gradient approximation (sp-GGA). The magnetic moment of the compound is calculated to be −0.00485, which although but small is important, as the value is negative, which is an indication of the presence of diamagnetism in Nb2C. Here, the detailed chemical etching process, magnetic properties of Nb2AlC MAX and its effect on magnetic phase of Nb2C MXene, and the density functional theory calculation are reported, which were not discussed by Babar et al. in ref. 8.  相似文献   
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