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Climate extremes pose severe threats to human health, economic stability and environmental sustainability, especially in densely populated areas. It is generally believed that global warming drives increase in frequency, intensity and duration of climate extremes, and socioeconomic exposure plays a dominant role in climate impacts. In order to promote climate risk governance at regional level, the historical and projected trends in the population exposure to climate extremes are quantified in eastern China using downscaled climate simulations and population growth scenarios. The frequency of temperature extremes (tx35days) is projected to more than double by 2050 in nearly half of prefecture-level cities in eastern China, leading to an 81.8% increment of total exposure under SSP2-4.5 scenario. The increasing trend is also detectable in the frequency of precipitation extremes (r20mm) in eastern China, and the exposure increment is projected to be 22.9% by 2050, with a near equivalent contributions of both climate change and population growth. Spatially, temperature exposure mainly grows in southern Hebei, western Shandong and inland Guangdong provinces, while precipitation exposure raises principally in southeast coastal areas of China. Based on the historical baseline and projected amplification of population exposure, we identify some hotspot cities such as Guangzhou, Shanghai, Dongguan and Hangzhou that response to climate change dramatically and confront greater potential risk of climate extremes in the coming future.

Abstract Recurrence is a challenge to survival after the initial treatment of esophageal squamous cell carcinoma (ESCC). But, its mechanism remains elusive and there are currently no biomarkers to predict postoperative recurrence. Here, the possibility of sterile alpha motif domain‐containing protein 9 (SAMD9) as a predictor of postoperative recurrence of ESCC is evaluated and the molecular mechanisms by which SAMD9 promotes ESCC recurrence are elucidated. The authors found that the high level of SAMD9 is correlated with postoperative recurrence and poor prognosis of ESCC. Overexpression of SAMD9 promotes tumor stemness, angiogenesis, and EMT, while downregulation of SAMD9 reduced these phenotypes. Mechanistically, it is found that SAMD9 stimulated ubiquitination‐mediated glycogen synthase kinase‐3 beta (GSK‐3β) degradation by interaction with myosin‐9 (MYH9) and TNF receptor‐associated factor 6 (TRAF6), which in turn activated Wnt/β‐catenin pathway. Further, the authors demonstrated that silencing SAMD9 inhibited lung metastasis and tumor formation in vivo. Finally, the authors found that silencing MYH9 or β‐catenin, or overexpressing GSK‐3β inhibited SAMD9‐stimulated ESCC cell stemness, EMT, angiogenesis, metastasis, and tumorigenicity. Together, the findings indicate that the SAMD9/MYH9/GSK3β/β‐catenin axis promotes ESCC postoperative recurrence and that SAMD9 is a crucial target for ESCC therapy. Additionally, SAMD9 has the potential as a predictor of postoperative recurrence in ESCC.

Aiming at the dynamic mechanical system with multiple failure correlation, the copula function is used to describe the correlation of failure modes among units, and a reliability model of dynamic mechanical system with multiple failure correlations is proposed. The reliability problem of complex system is transformed into multiple two-dimensional pair copula functions by using R-Vine copula function. The optimal R-Vine structure is selected by using MST algorithm. The time-varying parameters in the model are described by nonparametric kernel density estimation（KDE）. The common series parallel system（hybrid system） in mechanical system is modeled and analyzed. Finally, the effectiveness of the model is verified by an example of spacecraft open and close shafting.

Traditional vehicular edge computing research usually ignores the mobility of vehicles, the dynamic variability of the vehicular edge environment, the large amount of real‐time data required for vehicular edge computing, the limited resources of edge servers, and collaboration issues. In response to these challenges, this article proposes a vehicular edge computing optimization scheme based on the Lyapunov function and Deep Reinforcement Learning. In this solution, this article uses Digital Twin technology (DT) to simulate the vehicular edge environment. The edge server DT is used to simulate the vehicular edge environment under the edge server, and the base station DT is used to simulate the entire vehicular edge system environment. Based on the real‐time data obtained from DT simulation, this paper defines the Lyapunov function to simplify the migration cost of vehicle tasks between servers into a multi‐objective dynamic optimization problem. It solves the problem by applying the Twin Delayed Deep Deterministic Policy Gradient (TD3) algorithm. Experimental results show that compared with other algorithms, this scheme can effectively optimize the allocation and collaboration of vehicular edge computing resources and reduce the delay and energy consumption caused by vehicle task processing. [ABSTRACT FROM AUTHOR]

A comprehensive modeling framework for the thermoforming of polymer matrix woven laminate composite was developed. Two numerical indicators, the slip path length and traction magnitude, have been identified to be positively correlated to matrix smearing and wrinkling defects. The material model has been calibrated with picture-frame experimental results, and the prediction accuracy for intra-ply shear and thickness distribution was examined with measurements of the physically formed parts. Specifically, thickness prediction for most locations on the formed parts was accurate within an 11.6% error margin. However, at two points with significant intra-ply shear, the prediction errors increased to around 20%. Finally, a parametric study was conducted to determine the relationship between various process parameters and the quality of the formed part. For the trapezoidal part, orienting the laminate at 45 degrees to the mold axis reduces the likelihood of matrix smear and wrinkling defects. Although this laminate orientation yielded a greater spatial variation in part thickness, the thickness deviation is lower than that for the 0-degree orientation case. Two forming analyses were conducted with ramp rates of 25 mm/s and 80 mm/s to match the equipment's operational limits. It was observed that higher forming rates led to a greater likelihood of defects, as evidenced by a 15% and 10% increase in the formed part areas with longer slip paths and higher traction magnitudes, respectively. It was discovered that shallower molds benefit from faster ramp rates, while deeper molds require slower rates to manage extensive shearing, stretching and bending. Faster forming rates lead to smaller thickness increases at high intra-ply shear regions, indicating a shift from intra-ply shear to out-of-plane bending due to the visco-plastic effect of the molten laminate and can negatively impact part quality. Lastly, it was shown that a well-conceived strategy using darts could improve the part quality by reducing the magnitude of the defect indicators. [ABSTRACT FROM AUTHOR]

The neuroprotective potential of blueberry (BB) extracts against Alzheimer's disease (AD) has been previously hinted at, while its exact mechanism has remained largely enigmatic. Our study endeavored to unravel the impacts and mechanisms by which BB extracts ameliorated the learning and memory prowess of AD-afflicted mice, with a specific focus on the MEK-ERK pathway. We employed 3-month-old APP/PS1 transgenic mice and stratified them into three distinct groups: AD+BB, AD, and control (CT). The Morris Water Maze Test (MWMT) was then administered to gauge their learning and memory faculties. In vitro experiments were executed on Aβ25-35-afflicted rat hippocampal neurons, which were subsequently treated with varying concentrations of BB extracts. We then assessed the expression levels of genes and proteins integral to the MEK-ERKBDNF/UCH-L1 pathway. The data showed that the AD mice demonstrated compromised learning and memory faculties in MWMT. However, the AD+BB cohort showcased marked improvements in performance. Furthermore, in the AD subset, significant elevations in the expressions of MEK2 and ERK1/2 were observed, both at the mRNA and protein levels. Conversely, UCH-L1 mRNA expressions exhibited a decline, while BDNF expressions surged significantly. However, post BB extract treatment, the expressions of MEK2 and ERK1/2 were subdued, with UCH-L1 and BDNF mRNA expressions reverting to control levels. Our findings propounded that BB extracts could offer therapeutic promise for AD by bolstering learning and memory capacities. The unwarranted activation of the MEK-ERK pathway, coupled with the aberrant expressions of BDNF and UCH-L1, might underpin AD's pathogenesis. [ABSTRACT FROM AUTHOR]

AIM: To compare binocular visual quality of bilateral implantation of a toric bifocal intraocular lens(IOL)or a nontoric bifocal IOL and mix-and-match implantation of a toric bifocal IOL and a nontoric bifocal IOL.METHODS: A cross-sectional study. One hundred and eight eyes of 54 cases were included from January 2020 to January 2021. All participants were divided into three groups according to preexist corneal astigmatism and IOL type. In group A, cornea astigmatism was less than 1.0D in both eyes of 21 cases and bifocal IOLs were implanted. In group B, cornea astigmatism was more than 1.0D in both eyes of 15 cases and toric bifocal IOLs were implanted. In group C, 18 cases of one eye with cornea astigmatism less than 1.0D were implanted with bifocal IOLs, and the other eye with astigmatism more than 1.0D were implanted with toric bifocal IOLs. Preoperative intraocular pressure(IOP), monocular uncorrected distance visual acuity(UDVA), equivalent spherical, postoperative binocular corrected distance visual acuity(CDVA), UDVA, uncorrected intermediate visual acuity(UIVA), uncorrected near visual acuity(UNVA), residual astigmatism, defocus curve and contrast sensitivity were compared among the three groups. Postoperative questionnaire was conducted to evaluate the visual quality of the three groups.RESULTS: There were no significant differences in preoperative UDVA and IOP among the three groups(P>0.05). The postoperative residual astigmatism in group A was significantly higher than the other two groups(P=0.012, P0.5).CONCLUSION: Mix-and-match implantation of a toric bifocal IOL and nontoric bifocal IOL can effectively improve postoperative binocular visual quality in cataract patients. Correcting astigmatism helps improve the visual contrast sensitivity, however, when astigmatism is completely corrected, it may result in a loss of intermediate vision in patients after surgery.

Myopia has become an important public health problem to be solved urgently. Posterior chamber phakic implantable Collamer lens (ICL) implantation is one of the latest and safest products for myopia correction worldwide. This prospective cross-sectional case series aimed to observe changes in the macular retinal thickness, retinal nerve fiber layer (RNFL) thickness of para-optic disk region, and blood flow density after posterior ICL implantation in patients with high myopia using optical coherence tomography angiography (OCTA). A total of 67 eyes of 67 patients with high myopia, who underwent ICL implantation at The Affiliated Eye Hospital of Nanjing Medical University from January 2020 and December 2020, were included. The spherical equivalent (SE) of the operative eyes was >−6.00 D. The changes in vision, intraocular pressure (IOP), SE, and vault were observed pre-operatively, and follow-up were performed 1 week, 1 month, and 3 months. OCTA was used to observe the changes in the CRT, retinal thickness of paracentral fovea, FAZ, superficial and deep retinal blood flow density in the macular area, RNFL thickness of para-optic disk region, and blood flow density before and after ICL implantation. The uncorrected distance visual acuity (UDVA) and best corrected distance visual acuity (CDVA) of the patients post-operation were significantly improved (P < 0.001). The IOP increased in comparison with other time points at 1 week post-operation (P < 0.05). There were no significant changes in CRT post-operation. The retinal thickness in the upper, lower, nasal, and temporal quadrants of the paracentral fovea increased significantly at 1 month and 3 months post-operation (P < 0.05). The FAZ area at all postoperative time points were decreased (P < 0.001). At 3 months post-operation, the blood flow density of the superficial and deep retinal layers in the upper, lower, and nasal macular area were significantly reduced (P < 0.05). At 1 month post-operation, the RNFL thickness in the temporal para-optic disk region and blood flow density were significantly reduced (P = 0.001 and P < 0.05, respectively). ICL implantation for highly myopic eyes led to an increase of the retinal thickness in the upper, lower, nasal, and temporal regions of the paracentral fovea; reduction of RNFL thickness in the temporal area of para-optic disk; decrease in FAZ area; and decrease in the blood flow density of some deep and superficial retinal layers as well as that of the temporal para-optic disk region.

Although carbon dots (CDs) have been widely investigated as the fluorescence material, research on room temperature phosphorescence (RTP) CDs is still limited. In this work, diethylenetriaminepentaacetic acid (DTPA) was employed as the raw material to synthesize carbon quantum dots (denoted as CQDs-1) by a hydrothermal method. The resulting CQDs-1 inherited CO groups and N atoms from DTPA, which promoted the formation of triplet excitons under light excitation. On this basis, the CQDs-1 were dispersed in a poly-(vinyl alcohol) (PVA) matrix to prepare CQDs-1-PVA composites that exhibited an optimal emission peak at ∼466 nm and emitted the visible afterglow lasting for 8 s. Moreover, tartaric acid (TA) was combined with DTPA as the raw material to synthesize CQDs-2, which induced the formation of π–π conjugated areas in CQDs. As a result, the emission wavelength was slightly red-shifted, and the duration time of afterglow of the CQDs-2-PVA composite was increased to 9 s. Due to the ultralong-lifetime RTP properties of the CQDs-based composites, their applications in the fields of information encryption and anticounterfeiting have also been investigated. Overall, our work offered a convenient avenue for the synthesis of high-quality RTP CQDs. [ABSTRACT FROM AUTHOR]

Background: The association between vitamin D supplementation and the risk of falls in older adults has been controversial. This systematic review and network meta-analysis aims to assess the efficacy of vitamin D, calcium, and combined supplementation in the prevention of falls. Methods: Randomized controlled trials (RCTs) on the efficacy of vitamin D in fall prevention were systematically searched in PubMed, Embase, Cochrane Library, and Web of Science from inception to May 9, 2023. The network meta-analysis was performed using a random effects model in R4.1.3 and Stata15.0. Heterogeneity was evaluated by the I2 statistic, and publication bias was assessed using funnel plots, Begg's test, and Egger's tests. Data were pooled and expressed as relative risk (RR) and 95% confidence interval (CI). Results: A total of 35 RCTs involving 58,937 participants were included in this study, among which 11 RCTs (31.4%) applied calcium combined with vitamin D. There was low heterogeneity (I2 = 11%) among the included studies. Vitamin D supplementation at 800–1000 International Unit (IU)/d resulted in a lower risk of falls than placebo or no treatment (RR = 0.85, 95%CI: 0.74–0.95). In addition, 800–1000 IU/d of vitamin D with or without calcium were more effective in preventing falls than calcium alone. High-dose vitamin D (> 1000 IU/day) increased the risk of falls compared with 800–1000 IU/d of vitamin D. According to the subgroup analysis, daily administration of 800–1000 IU/d vitamin D was associated with a 22% reduction in the risk of falls (RR = 0.78, 95%CI:0.64–0.92), whereas intermittent vitamin D administration had no preventive effect. Furthermore, 800–1000 IU/d of vitamin D also significantly decreased the risk of falls in old adults with ≤ 50 nmol/L 25-hydroxyvitamin D [25(OH)D] (RR = 0.69, 95%CI:0.52–0.86) but not in individuals with > 50 nmol/L 25(OH)D. Conclusion: Vitamin D supplementation at 800–1000 IU/d is associated with a lower risk of falls among older adults. 800-1000IU/d of vitamin D has a benefit on prevention of falls in population received daily dose regimens and in population with vitamin D deficiency. [ABSTRACT FROM AUTHOR]