Background: Although much is known about the association between dietary glycemic load (GL) and type 2 diabetes (T2D), prospective cohort studies have not consistently shown a positive dose-response ...relation.Objective: We performed a comprehensive examination of evidence on the dose response that links GL to T2D and sources of heterogeneity among all prospective cohort studies on healthy adults available in the literature.Design: We conducted a systematic review of all prospective cohort studies and meta-analyses to quantify the GL-T2D relation both without and with adjustment for covariates.Results: Among 24 prospective cohort studies identified by August 2012, the GL ranged from ∼60 to ∼280 g per daily intake of 2000 kcal (8.4 MJ). In a fully adjusted meta-analysis model, the GL was positively associated with RR of T2D of 1.45 (95% CI: 1.31, 1.61) for a 100-g increment in GL (P < 0.001; n = 24 studies; 7.5 million person-years of follow-up). Sex (P = 0.03), dietary instrument validity (P < 0.001), and ethnicity (European American compared with other; P = 0.04) together explained 97% of the heterogeneity among studies. After adjustment for heterogeneities, we used both funnel and trim-and-fill analyses to identify a negligible publication bias. Multiple influence, cumulative, and forecast analyses indicated that the GL-T2D relation tended to have reached stability and to have been underestimated. The relation was apparent at all doses of GL investigated, although it was statistically significant only at >95 g GL/2000 kcal.Conclusion: After we accounted for several sources of heterogeneity, findings from prospective cohort studies that related the GL to T2D appear robust and consistently indicate strong and significantly lower T2D risk in persons who consume lower-GL diets. This review was registered at http://www.crd.york.ac.uk/PROSPERO as CRD42011001810.
Developing more extensive methods to understand the underlying structure-property relationship of mechanochromic luminescent molecules is demanding but remains challenging. Herein, the effect of ...host-guest interaction on the mechanochromic properties of organic molecules is illustrated. A series of pyridinium-functionalized triphenylamine derivatives show bathochromic-shifted emission upon mechanical stimulation. These derivatives bind to cucurbit8uril to form homoternary host-guest inclusion complexes through host-stabilized intermolecular charge transfer interactions. Remarkably, the homoternary complexes exhibit longer emission than that of free guests in the solid state (even longer than ground guests), and a further bathochromic-shifted emission is observed upon grinding. Additionally, a heteroternary complex constructed through the encapsulation of pyrene (donor) and pyridinium (acceptor) guest pair in cucurbit8uril also displays the mechanochromic luminescent property. This work not only discloses the effect of host-guest inclusion on the mechanochromic property of organic molecules, but also provides a principle and a facile way to design the sequentially red-shifted mechanochromic materials.
High-resolution diffusion MRI (dMRI) is a crucial tool in neuroscience studies to detect fine fiber structure, depict complex fiber architecture and analyze cortical anisotropy. However, ...high-resolution dMRI is limited by its intrinsically low SNR due to diffusion attenuation. A series of techniques have been proposed to improve the SNR performance, but most of them are at the cost of long scan time, which in turn sacrifice the SNR efficiency, especially for large FOV imaging, such as whole-brain imaging. Recently, a combination of 3D multi-slab acquisition and simultaneous multi-slice (SMS) excitation, namely simultaneous multi-slab (SMSlab), has been demonstrated to have potential for high-resolution diffusion imaging with high SNR and SNR efficiency. In our previous work, we have proposed a 3D Fourier encoding and reconstruction framework for SMSlab acquisition. In this study, we extend this 3D k-space framework to diffusion imaging, by developing a novel navigator acquisition strategy and exploring a k-space-based phase correction method. In vivo brain data are acquired using the proposed SMSlab method and compared with a series of different acquisitions, including the traditional 3D multi-slab, 2D SMS and 2D single-shot EPI (ss-EPI) acquisitions. The results demonstrate that SMSlab has a better SNR performance compared with 3D multi-slab and 2D SMS. The detection capacity of fine fiber structures is improved using SMSlab, compared with the low-resolution diffusion imaging using conventional 2D ss-EPI.
Diarylethene (DTE) has been widely used in fluorescence probes, molecular logic gates, optical data‐storage devices owing to the excellent photochromic property, while constructing high‐performance ...photochromic DTE in aqueous media remains a big challenge. Herein we present several host‐guest systems formed between cucurbitnuril (CBn, n=7, 8, 10) and two water‐soluble DTE derivatives 1 and 2. It was found that host‐guest interactions not only affect the photophysical properties of photochromic guests, but also make great differences on the photoreaction process. Different host‐guest binding behaviors also lead to different effects on the photochromic properties of guests. In the presence of CBn, both 1 and 2 showed enhanced emission and higher fluorescence quenching ratio at photostationary state. Besides, CB10⋅1 exhibited faster response rate in cyclization reaction and better photofatigue resistance than free 1 in aqueous solution, while the supramolecular assembly of (CB8)n⋅(2)n showed slower response rate in both directions of the reversible photoreaction. Besides, the photofatigue resistance of 2 can be greatly improved through binding with CB7. Our results suggest that host‐guest interactions could be an efficient way to improve photochromic properties of DTE in aqueous solution.
In the presence of CBn host, the photophysical and photochemical properties of diarylethene derivatives (DTEs) were significantly affected. With suitable CBn, DTEs showed faster response rate, better fatigue resistance, and higher fluorescence quenching ratio, suggesting that high‐performance photochromic system in aqueous solution can be constructed through CBn‐based host‐guest interactions.
Abstract Objective We aimed to systematically review available literature linking adipokines to gestational diabetes mellitus (GDM) for a comprehensive understanding of the roles of adipokines in the ...development of GDM. Methods We searched PubMed/MEDLINE and EMBASE databases for published studies on adipokines and GDM through October 21, 2014. We included articles if they had a prospective study design (i.e., blood samples for adipokines measurement were collected before GDM diagnosis). Random-effects models were used to pool the weighted mean differences comparing levels of adipokines between GDM cases and non-GDM controls. Results Of 1523 potentially relevant articles, we included 25 prospective studies relating adipokines to incident GDM. Our meta-analysis of nine prospective studies on adiponectin and eight prospective studies on leptin indicated that adiponectin levels in the first or early second trimester of pregnancy were 2.25 μg/ml lower (95% CI: 1.75–2.75), whereas leptin levels were 7.25 ng/ml higher (95% CI 3.27–11.22), among women who later developed GDM than women who did not. Prospective data were sparse and findings were inconsistent for visfatin, retinol binding protein (RBP-4), resistin, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and vaspin. We did not identify prospective studies for several novel adipokines, including chemerin, apelin, omentin, or adipocyte fatty acid-binding protein. Moreover, no published prospective studies with longitudinal assessment of adipokines and incident GDM were identified. Conclusion Adiponectin levels in the first or second trimester of pregnancy are lower among pregnant women who later develop GDM than non-GDM women, whereas leptin levels are higher. Well-designed prospective studies with longitudinal assessment of adipokines during pregnancy are needed to understand the trajectories and dynamic associations of adipokines with GDM risk.
By the replacement of halogen anion, three new multifunctional organic-inorganic hybrid perovskites (thiomorpholinium)PbX3 (X = Cl, Br, I) were successfully synthesized and underwent reversible ...structural transformation above room temperature, accompanied by the anomalous change of dielectric constant. With the adjustment of the halogen anion from Cl to I in the inorganic skeleton, the space group is transformed from centrosymmetric space group P21/c ((thiomorpholinium)PbCl3) to chiral one P212121 ((thiomorpholinium)PbBr3, (thiomorpholinium)PbI3) at room temperature. The ordered-disordered transition of organic cations and the change of hydrogen bonds with the increase of temperature lead to above-room-temperature phase transitions. Ultraviolet absorption and second-harmonic generation (SHG) measurements confirmed that both the band gap and SHG activity of (thiomorpholinium)PbX3 (X = Cl, Br, I) crystals were tunable. The band gaps reveal a broadening trend with 3.532 eV, 3.410 eV and 3.175 eV along the Cl → Br → I series. This work provides an effective molecular design for multifunctional organic-inorganic perovskites.
Tunable phase transition, band gap and SHG properties by halogen replacement of hybrid perovskites (thiomorpholinium)PbX3, X = Cl, Br, I
. By the replacement of the halogen anions, we synthesized new one-dimensional ABX3-type perovskites, (thiomorpholinium)PbX3, X = Cl, Br, I which underwent reversible phase transitions. And the band gap and SHG activity of (thiomorpholinium)PbX3 (X = Cl, Br, I) crystals were tunable. Display omitted
Guidelines recommend exercise for cardiovascular health, although evidence from trials linking exercise to cardiovascular health through intermediate biomarkers remains inconsistent. We performed a ...meta-analysis of randomized controlled trials to quantify the impact of exercise on cardiorespiratory fitness and a variety of conventional and novel cardiometabolic biomarkers in adults without cardiovascular disease.
Two researchers selected 160 randomized controlled trials (7487 participants) based on literature searches of Medline, Embase, and Cochrane Central (January 1965 to March 2014). Data were extracted using a standardized protocol. A random-effects meta-analysis and systematic review was conducted to evaluate the effects of exercise interventions on cardiorespiratory fitness and circulating biomarkers. Exercise significantly raised absolute and relative cardiorespiratory fitness. Lipid profiles were improved in exercise groups, with lower levels of triglycerides and higher levels of high-density lipoprotein cholesterol and apolipoprotein A1. Lower levels of fasting insulin, homeostatic model assessment-insulin resistance, and glycosylated hemoglobin A1c were found in exercise groups. Compared with controls, exercise groups had higher levels of interleukin-18 and lower levels of leptin, fibrinogen, and angiotensin II. In addition, we found that the exercise effects were modified by age, sex, and health status such that people aged <50 years, men, and people with type 2 diabetes, hypertension, dyslipidemia, or metabolic syndrome appeared to benefit more.
This meta-analysis showed that exercise significantly improved cardiorespiratory fitness and some cardiometabolic biomarkers. The effects of exercise were modified by age, sex, and health status. Findings from this study have significant implications for future design of targeted lifestyle interventions.
To achieve the goals of national emission reduction, carbon peak and carbon neutralization, different provinces will face extremely limited and strict carbon emission space. How to allocate these ...limited carbon emission spaces is not only related to the realization of emission reduction targets, but also the development of the social economy. There are significant differences in resource endowments and development stages among provinces in China, and the industrial structure is very different. The allocation of carbon quotas under the path of carbon neutrality is particularly important. Based on the carbon-neutral path simulated by existing research, this paper selects population size, GDP value, historical cumulative carbon emissions and carbon emission efficiency indicators calculated by the Super-SBM model from the perspective of fairness and efficiency to allocate carbon quotas in each province. The results show that Guangdong has the largest proportion of 8 %, Jiangsu ranks second with 5 %, and Henan ranks third with nearly 5 %. Xinjiang, Qinghai and Ningxia has the lowest proportion of quotas, 1.7 %, 0.88 % and 0.72 % respectively. Overall, well-developed provinces (Guangdong, Jiangsu) and populous provinces (Henan, Shandong, Sichuan) have an advantage in distribution due to higher carbon emission efficiency and larger population size. In some underdeveloped regions, carbon quotas are low due to low economic development levels, small population scale and low carbon emission efficiency. Meanwhile, in some high emission provinces, such as Inner Mongolia, Ningxia, Shanxi and Xinjiang, due to the high historical cumulative carbon emissions per capita, the quota is less.
Numerous studies have suggested that excess body weight is associated with increased cancer risk. To examine this putative association, we performed a systematic review and quantitative meta‐analysis ...of cohort studies reporting body mass index (BMI) and the risk of 23 cancer types. PubMed, Embase, and Web of Science were searched for cohort studies, yielding 325 articles with 1,525,052 cases. Strong positive associations were observed between BMI and endometrial cancer (RR: 1.48), esophageal adenocarcinoma (RR: 1.45), and kidney cancer (RR: 1.20); weaker associations (RR < 1.20) were also found for several other cancer types. Interestingly, we found significant inverse associations between BMI and oral cavity (RR: 0.93), lung (RR: 0.91), premenopausal breast (RR: 0.95), and localized prostate (RR: 0.97) cancers. A male‐specific association was found for colorectal cancer (p = 0.023), and a female‐specific association was found for cancer in brain (p = 0.025) or kidney (p = 0.035). With respect to geography, the strongest positive association was found for total cancer in North America (p = 0.038). This comprehensive meta‐analysis provides epidemiological evidence supporting the association between BMI and cancer risk. These findings can be used to drive public policies and to help guide personalized medicine in order to better manage body weight, thereby reducing the risk of developing obesity‐related cancer.
What's new?
Recent studies have uncovered a startling rise in global prevalence of overweight and obesity among adults since the 1980s, raising new concerns about associations between obesity and cancer risk. The authors of the present study reassessed associations between obesity and different cancers. Analyses revealed positive associations between body mass index (BMI) and multiple cancer types, with several gender‐specific and geography‐specific associations. Geographically, the strongest positive association between obesity and total cancer was in North America. The findings, which are relevant for public health, could also help guide personalized efforts to improve body weight management and thereby reduce cancer risk.
The development of ultrahigh-surface-area biomass-based carbonaceous electrode materials is a major science and engineering challenge for high-performance supercapacitors. Here we present a type of ...highly porous carbon material derived from waste bagasse by the purposeful combination of hydrothermal carbonization with chemical activation. The obtained waste bagasse-based carbon materials not only exhibit a valuable hierarchically porous structure with a honeycomb-like texture but also have a very high specific surface area. The highest specific surface area reaches 3151 m2 g–1, which is superior to those of other bagasse-based porous carbons reported so far. Benefiting from the combination of hierarchical pore structure and well-developed porosity, such a type of carbon materials serves very well when used as electrodes in both 1.0 and 1.8 V aqueous supercapacitors. For example, the as-prepared carbon electrode gives a high capacitance of 413 F g–1 at 1 A g–1 and a satisfied cycling stability of 93.4% capacitance retention after 10000 cycles in 1.0-V aqueous supercapacitors. A remarkably high energy density of 22.3 Wh kg–1 at a power density of 220.9 W kg–1 can be achieved in 1.8-V aqueous symmetrical supercapacitors. These very attractive electrochemical performances enable this highly porous carbon to go far beyond many previously reported carbonaceous electrodes, which presents a great potential for bridging the electrochemical performance gap between conventional nonaqueous and aqueous supercapacitors and opens up new avenues to high-value materials from waste bagasse.
PDF
