When reporting the results of clinical studies, some researchers may choose the five‐number summary (including the sample median, the first and third quartiles, and the minimum and maximum values) ...rather than the sample mean and standard deviation (SD), particularly for skewed data. For these studies, when included in a meta‐analysis, it is often desired to convert the five‐number summary back to the sample mean and SD. For this purpose, several methods have been proposed in the recent literature and they are increasingly used nowadays. In this article, we propose to further advance the literature by developing a smoothly weighted estimator for the sample SD that fully utilizes the sample size information. For ease of implementation, we also derive an approximation formula for the optimal weight, as well as a shortcut formula for the sample SD. Numerical results show that our new estimator provides a more accurate estimate for normal data and also performs favorably for non‐normal data. Together with the optimal sample mean estimator in Luo et al., our new methods have dramatically improved the existing methods for data transformation, and they are capable to serve as “rules of thumb” in meta‐analysis for studies reported with the five‐number summary. Finally for practical use, an Excel spreadsheet and an online calculator are also provided for implementing our optimal estimators.
The increased social and economic burdens for osteoporosis-related fractures worldwide make the prevention of such injuries a major public health goal. Previous studies have reached mixed conclusions ...regarding the association between calcium, vitamin D, or combined calcium and vitamin D supplements and fracture incidence in older adults.
To investigate whether calcium, vitamin D, or combined calcium and vitamin D supplements are associated with a lower fracture incidence in community-dwelling older adults.
The PubMed, Cochrane library, and EMBASE databases were systematically searched from the inception dates to December 24, 2016, using the keywords calcium, vitamin D, and fracture to identify systematic reviews or meta-analyses. The primary randomized clinical trials included in systematic reviews or meta-analyses were identified, and an additional search for recently published randomized trials was performed from July 16, 2012, to July 16, 2017.
Randomized clinical trials comparing calcium, vitamin D, or combined calcium and vitamin D supplements with a placebo or no treatment for fracture incidence in community-dwelling adults older than 50 years.
Two independent reviewers performed the data extraction and assessed study quality. A meta-analysis was performed to calculate risk ratios (RRs), absolute risk differences (ARDs), and 95% CIs using random-effects models.
Hip fracture was defined as the primary outcome. Secondary outcomes were nonvertebral fracture, vertebral fracture, and total fracture.
A total of 33 randomized trials involving 51 145 participants fulfilled the inclusion criteria. There was no significant association of calcium or vitamin D with risk of hip fracture compared with placebo or no treatment (calcium: RR, 1.53 95% CI, 0.97 to 2.42; ARD, 0.01 95% CI, 0.00 to 0.01; vitamin D: RR, 1.21 95% CI, 0.99 to 1.47; ARD, 0.00 95% CI, -0.00 to 0.01. There was no significant association of combined calcium and vitamin D with hip fracture compared with placebo or no treatment (RR, 1.09 95% CI, 0.85 to 1.39; ARD, 0.00 95% CI, -0.00 to 0.00). No significant associations were found between calcium, vitamin D, or combined calcium and vitamin D supplements and the incidence of nonvertebral, vertebral, or total fractures. Subgroup analyses showed that these results were generally consistent regardless of the calcium or vitamin D dose, sex, fracture history, dietary calcium intake, and baseline serum 25-hydroxyvitamin D concentration.
In this meta-analysis of randomized clinical trials, the use of supplements that included calcium, vitamin D, or both compared with placebo or no treatment was not associated with a lower risk of fractures among community-dwelling older adults. These findings do not support the routine use of these supplements in community-dwelling older people.
Lithium (Li) metal is a promising anode material for high‐energy density batteries. However, the unstable and static solid electrolyte interphase (SEI) can be destroyed by the dynamic Li ...plating/stripping behavior on the Li anode surface, leading to side reactions and Li dendrites growth. Herein, we design a smart Li polyacrylic acid (LiPAA) SEI layer high elasticity to address the dynamic Li plating/stripping processes by self‐adapting interface regulation, which is demonstrated by in situ AFM. With the high binding ability and excellent stability of the LiPAA polymer, the smart SEI can significantly reduce the side reactions and improve battery safety markedly. Stable cycling of 700 h is achieved in the LiPAA‐Li/LiPAA‐Li symmetrical cell. The innovative strategy of self‐adapting SEI design is broadly applicable, providing opportunities for use in Li metal anodes
Stretching exercises: A flexible lithium polyacrylic acid (LiPAA) solid electrolyte interphase (SEI) layer which is highly stretchable is designed to address the dynamic volume changes during Li plating/stripping on the Li anode surface in Li ion batteries. The LiPAA polymer SEI can significantly reduce the side reactions and improve the safety performance.
Aqueous rechargeable batteries (ARBs) offer advantages in terms of safety, environmental friendliness and cost over their non‐aqueous counterparts. However, the narrow electrochemical stability ...window of water inherently limits the output voltage and energy density of ARBs. Here, a system with an aqueous hybrid electrolyte containing a Zn anode in alkaline solution and LiMn2O4 cathode in neutral solution is reported. Combining the separated electrode‐electrolyte with a Li+‐conducting membrane, the potential window is effectively widened to enable an aqueous hybrid electrolyte rechargeable battery (AHERB) above 2.3 V. This battery system delivers a steady energy density of 208 Wh kg−1 (based on the total weight of active materials) at 1.69 C with a high average output voltage up to 2.31 V, cycled for over 1000 cycles with an average Coulombic efficiency of >98%.
An alkaline‐neutral hybrid electrolyte system, which has a wide electrochemical stability window of 3 V, is assembled with a Li+‐conducting membrane. Taking advantage of such an electrolyte system, an aqueous hybrid electrolyte rechargeable battery system (AHERBs) consisting of Zn anode and LiMn2O4 cathode delivers a high average output voltage, high energy density, and excellent cycling performance.
Hedgehog (Hh) pathway controls complex developmental processes in vertebrates. Abnormal activation of Hh pathway is responsible for tumorigenesis and maintenance of multiple cancers, and thus ...addressing this represents promising therapeutic opportunities. In recent years, two Hh inhibitors have been approved for basal cell carcinoma (BCC) treatment and show extraordinary clinical outcomes. Meanwhile, a series of novel agents are being developed for the treatment of several cancers, including lung cancer, leukemia, and pancreatic cancer. Unfortunately, Hh inhibition fails to show satisfactory benefits in these cancer types compared with the success stories in BCC, highlighting the need for better understanding of Hh signaling in cancer. Autophagy, a conserved biological process for cellular component elimination, plays critical roles in the initiation, progression, and drug resistance of cancer, and therefore, implied potential to be targeted. Recent evidence demonstrated that Hh signaling interplays with autophagy in multiple cancers. Importantly, modulating this crosstalk exhibited noteworthy capability to sensitize primary and drug-resistant cancer cells to Hh inhibitors, representing an emerging opportunity to reboot the efficacy of Hh inhibition in those insensitive tumors, and to tackle drug resistance challenges. This review will highlight recent advances of Hh pathway and autophagy in cancers, and focus on their crosstalk and the implied therapeutic opportunities.
Solid electrolytes (SEs) can potentially address the inherent safety problems of conventional organic liquid electrolytes. However, their low ionic conductivity and large interfacial resistance limit ...the practical applications of SEs. Here, a flexible solid electrolyte with a multilayer structure is fabricated by the UV curing of an interpenetrating network of poly(ether‐acrylate) (ipn‐PEA) in the Na3Zr2Si2PO12/poly(vinylidene fluoride‐hexafluoropropylene) porous skeleton (NZSP/PVDF‐HFP), exhibiting a high Na+ transference number of 0.63 and a suitable ionic conductivity of above 10−4 S cm−1 at 60 °C. In addition, due to the unique structure of the internal rigidity and external flexibility, the composite solid electrolyte can effectively mitigate interfacial ion transfer issues while guaranteeing a certain mechanical strength, and largely inhibiting the formation of dendrite and dead sodium. The solid sodium metal batteries using Na3V2(PO4)3 (NVP) as a cathode possess a discharge capacity of 85 mA h g−1 after 100 cycles at 0.5 C, and achieve above 90% of capacity retention rate during 100 cycles at 0.1 C for Na2/3Ni1/3Mn1/3Ti1/3O2 (NTMO) at 60 °C. The flexible solid electrolyte with multilayer structure shows a great advantage for managing the ionic conductivity and interface resistance problem, suggesting a promise as a practical sodium metal battery.
A flexible composite electrolyte with a sandwich structure (CESS) is fabricated by the UV curing of poly(ether‐acrylate) (ipn‐PEA) in a Na3Zr2Si2PO12/poly(vinylidene fluoride‐hexafluoropropylene) porous skeleton (NZSP/PVDF‐HFP). The internal rigidity and external flexibility of the CESS multilayer structure can effectively mitigate interfacial ion transfer issues while conferring a degree of mechanical strength, as such it shows tremendous application potential for sodium metal batteries.
Catalytic methods allowing for the reliable prediction and control of diverse regioselectivity along with the control of enantioselectivity to access different regio‐ and enantiomers by switching the ...least reaction parameters are one of the most attractive ways in organic synthesis, which provide access to diverse enantioenriched architectures from identical starting materials. Herein, a Co‐catalyzed regiodivergent and enantioselective reductive hydroalkylation of 1,3‐dienes with aldehydes has been achieved, furnishing different enantioenriched homoallylic alcohol architectures in good levels of enantioselectivity. The reaction features the switch of regioselectivity tuned by the selection of proton source. The use of an acid as proton source provided asymmetric 1,2‐hydroalkylation products under reductive conditions, yet asymmetric 4,3‐hydroalkylation products were obtained with silane as hydride source. This catalytic protocol allows for the access of homoallylic alcohols with two continuous saturated carbon centers in good levels of regio‐, diastereo‐, and enantioselectivity.
Catalytic methods to access different regio‐ and enantiomers by switching the least reaction parameters are attractive yet challenging. Herein, a Co‐catalyzed regiodivergent and enantioselective reductive hydroalkylation of 1,3‐dienes with aldehydes have been achieved, allowing for regio‐switchable 1,2‐hydroalkylation and 4,3‐hydroalkylation of 1,3‐dienes to furnish different homoallylic alcohol architectures from identical starting materials.
A hybrid solid/liquid electrolyte with superior security facilitates the implementation of high‐energy‐density storage devices, but it suffers from inferior chemical compatibility with cathodes. ...Herein, an optimal lithium difluoro(oxalato)borate salt was introduced to build in situ an amorphous cathode electrolyte interphase (CEI) between Ni‐rich cathodes and hybrid electrolyte. The CEI preserves the surface structure with high compatibility, leading to enhanced interfacial stability. Meanwhile, the space‐charge layer can be prominently mitigated at the solid/solid interface via harmonized chemical potentials, acquiring promoted interfacial dynamics as revealed by COMSOL simulation. Consequently, the amorphous CEI integrates the bifunctionality to provide an excellent cycling stability, high Coulombic efficiency, and favorable rate capability in high‐voltage Li‐metal batteries, innovating the design philosophy of functional CEI strategy for future high‐energy‐density batteries.
The CEI's advantage: An amorphous cathode electrolyte interphase (CEI) with superior chemical compatibility and plasticity was formed via in situ LiDFOB conversion. It endows high‐voltage hybrid solid/liquid batteries with significantly enhanced interfacial stability, durability, and dynamics.
Aliphatic trifluoromethyl ketones are a type of unique fluorine-containing subunit which plays a significant role in altering the physical and biological properties of molecules. However, catalytic ...methods to provide direct access to aliphatic trifluoromethyl ketones is highly desirable yet remains underdeveloped, partially due to the high reactivity and instability of trifluoroacetyl radical. Herein, we report a photocatalytic synthesis of trifluoromethyl ketones from alkyl bromides with trifluoroacetic anhydride. The reaction features a dual catalysis of visible-light and XAT reaction, followed by an enabling radical-radical cross-coupling of alkyl radical with a stabilized trifluoromethyl radical. The reaction provides the first straightforward access to aliphatic trifluoromethyl ketones from easily-available and cost-effective alkyl halides and TFAA.
Exploring the governance mechanisms of industrial carbon emissions in heavy industrial zones under the background of ecological civilization construction is of great significance to achieve the goal ...of 'double carbon' and environmental justice. With Liaoning heavy industrial zones as an example, we constructed a tripartite evolutionary game model of local government, industrial enterprises and third-party verification institutions. We examined the key factors affecting the strategic choice of industrial carbon emission tripartite stakeholders. The strategic choices of three stakeholders under different equilibrium points were simulated, and the industrial carbon emission governance mechanisms were constructed. The results showed that the stakeholder strategy choices of industrial carbon emissions under different equilibrium circumstances in the study area were in line with the reality and ideal respectively. In different equilibrium situations of tripartite stakeholder game, local governments, and third-party
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