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(K,Na)NbO3-based ceramics are deemed among the most promising lead-free piezoelectric materials, though their overall piezoelectric performance still lags behind the mainstream lead-containing counterparts. Here, we achieve an ultrahigh piezoelectric charge coefficient d33 ∼ 807 pC·N−1, along with a high longitudinal electromechanical coupling factor (k33 ∼ 88%) and Curie temperature (Tc ∼ 245 °C) in the (K,Na)(Nb1-xSbx)O3-Bi0.5Na0.5ZrO3-BiFeO3 (KNN-xSb) system through structural flexibility and grain orientation strategies. Phenomenological models, phase field simulations and high-angle annular dark-field scanning transmission electron microscopy reveal that the structural flexibility originates from the high Coulomb force between K+/Na+ ions and Sb ions in the KNN-xSb system, while the grain orientation promotes the displacement of B-site cations leveraging the engineered domain configuration. As a result of its excellent comprehensive piezoelectric properties, the textured KNN-5Sb/epoxy 1-3 piezoelectric composite is found to possess a broader bandwidth BW = 60% and higher amplitude output voltage than commercial PZT-5 and other KNN counterparts. These findings suggest that the textured KNN-5Sb ceramics could potentially replace current lead-based piezoceramics in transducer applications. The authors achieve piezoelectric coefficient d33 ∼ 807 pC·N−1, along with high k33 ∼ 88 % and Tc ∼ 245 °C in (K,Na)(Nb1-xSbx)O3-Bi0.5Na0.5ZrO3-BiFeO3 system through structural flexibility and grain orientation strategies. [ABSTRACT FROM AUTHOR]

It remains unclear whether the benefits of adhering to a healthy lifestyle outweigh the effects of high genetic risk on cognitive decline. We examined the association of combined lifestyle factors and genetic risk with changes in cognitive function and six specific dimensions of cognition among older adults from the Chinese Longitudinal Healthy Longevity Survey (1998–2018, n = 18,811, a subset of 6301 participants with genetic information). Compared to participants with an unfavorable lifestyle, those with a favorable lifestyle showed a 46.81% slower rate of cognitive decline, with similar results across most cognitive domains. High genetic risk was associated with a 12.5% faster rate of cognitive decline. Individuals with a high genetic risk and a favorable lifestyle have slower cognitive decline than those with a low genetic risk and an unfavorable lifestyle. These data suggest that the benefits of a favorable lifestyle outweigh genetic factors, and therefore that adhering to a favorable lifestyle may offset the genetic risk for accelerated cognitive decline. It remains unclear if the benefits of a healthy lifestyle outweigh the influence of genetics on the risk of cognitive decline in older adults. Here the authors find that adherence to a favorable lifestyle even in late-life might offset the genetic risk for accelerated cognitive decline. [ABSTRACT FROM AUTHOR]

The contradiction between high piezoelectricity and uniquely poor temperature stability generated by polymorphic phase boundary is a huge obstacle to high-performance (K, Na)NbO3 -based ceramics entering the application market as Pb-based substitutes. We possess the phase boundary by mimicking Pb(Zr, Ti)O3's morphotropic phase boundary structure via the synergistic optimization of diffusion phase boundary and crystal orientation in 0.94(Na0.56K0.44)NbO3−0.03Bi0.5Na0.5ZrO3−0.03(Bi0.5K0.5)HfO3 textured ceramics. As a result, a prominent comprehensive performance is obtained, including giant d33 of 550 ± 30 pC/N and ultrahigh temperature stability (d33 change rate less than 1.2% within 25-150 °C), representing a significant breakthrough in lead-free piezoceramics, even surpassing the Pb-based piezoelectric ceramics. Within the same temperature range, the d33 change rate of the commercial Pb(Zr, Ti)O3−5 ceramics is only about 10%, and more importantly, its d33 (~ 350 pC/N) is much lower than that of the (K, Na)NbO3-based ceramics in this work. This study demonstrates a strategy for constructing the phase boundary with MPB feature, settling the problem of temperature instability in (K, Na)NbO3-based ceramics. The authors induce a phase boundary similar to Pb(Zr, Ti)O3's morphotropic phase boundary structure in (K, Na)NbO3-based ceramics, which exhibit high residual polarization as well as a significantly improved piezoelectric constant d33. [ABSTRACT FROM AUTHOR]

Electrocaloric refrigeration which is environmentally benign has attracted considerable attention. In distinction to ferroelectric materials, which exhibit an extremely high positive electrocaloric effect near the Curie temperature, antiferroelectric materials represented by PbZrO3 have a specific negative electrocaloric effect, i.e., electric field decreases the temperature of the materials. However, the explanation of the microscopic mechanism of the negative electrocaloric effect is still unclear, and further research is still needed to provide a theoretical basis for the negative electrocaloric effect enhancement. Herein, the antiferroelectric phase-field model has been proposed to design polar boundaries enhancing antiferroelectric negative electrocaloric performance in PbZrO3-based materials. Based on this, we have simulated the polarization response and domain switching process of the temperature and electric field-induced antiferroelectric—ferroelectric phase transition. It is shown that the temperature range tends to increase as the density of polar boundaries increases from the antiferroelectric stripe domain, polymorphic domain to the nanodomain. Among them, the peak adiabatic temperature change of antiferroelectric nanodomains can reach −13.05 K at 84 kV/cm, and a wide temperature range of about 75 K can be realized at 42 kV/cm. We expect these discoveries to spur further interest in the potential applications of antiferroelectric materials for next-generation refrigeration devices. [ABSTRACT FROM AUTHOR]

Ferroelectricity in crystalline hafnium oxide has attracted considerable attention because of its potential application for memory devices. A recent breakthrough involves electric-field-induced crystallization, allowing HfO2-based materials to avoid high-temperature crystallization, which is unexpected in the back-end-of-line process. However, due to the lack of clarity in understanding the mechanisms during the crystallization process, we aim to employ theoretical methods for simulation, to guide experimental endeavors. In this work, we extended our phase-field model by coupling the crystallization model and time-dependent Ginzburg-Landau equation to analyze the crystalline properties and the polarization evolution of Hf0.5Zr0.5O2 thin film under applying an electric field periodic pulse. Through this approach, we found a wake-up effect during the process of crystallization and a transformation from orthorhombic nano-domains to the stripe domain. Furthermore, we have proposed an innovative artificial neural synapse concept based on the continuous polarization variation under applied electric field pulses. Our research lays the theoretical groundwork for the advancement of electric-field-induced crystallization in the hafnium oxide system. [ABSTRACT FROM AUTHOR]

Tropical cyclones (TCs) are expected to produce more intense precipitation under global warming. However, substantial uncertainties exist in the projection of coarse-resolution global climate models. Here, we use deep learning to aid targeted cloud-resolving simulations of extreme TCs. Contrary to the Clausius-Clapeyron (CC) scaling, which indicates a 7% moisture increase per K warming, our simulations reveal more complex responses of TC rainfall. TCs will not intensify via strengthened updrafts but through the expansion of deep convective cores with suppression of shallow cumulus and congestus. Consequently, while localized hourly rainfall may adhere to the CC scaling, precipitation accumulation over city-sized areas could surge by 18%K-1. This super-CC intensification due to changing TC structure has profound implications for floods and landslides. Estimations using Hong Kong's slope data confirm this concern and suggest an up to 215% increase in landslide risks with 4-K warming, highlighting amplified threats from compound disasters under climate change. [ABSTRACT FROM AUTHOR]

The development of high-performance lead-free K0.5Na0.5NbO3-based piezoceramics for replacing commercial lead-containing counterparts is crucial for achieving environmentally sustainable society. Although the proposed new phase boundaries (NPB) can effectively improve the piezoelectricity of KNN-based ceramics, the difficulty of achieving saturated poling and the underlying multiscale structures resolution of their complex microstructures are urgent issues. Here, we employ a medium entropy strategy to design NPB and utilize texture engineering to induce crystal orientation. The developed K0.5Na0.5NbO3-based ceramics enjoys both prominent piezoelectric performance and satisfactory Curie temperature, thus exhibiting an ultrahigh energy harvesting performance as well as excellent transducer performance, which is highly competitive in both lead-free and lead-based piezoceramics. Comprehensive structural analysis have ascertained that the field-induced efficient multiscale polarization configurations irreversible transitions greatly encourages high saturated poling. This study demonstrates a strategy for designing high-performance piezoceramics and establishes a close correlation between the piezoelectricty and the underlying multiscale structures. There are difficulty of achieving saturated poling and understanding of multi-scale structures in (K, Na)NbO3 ceramics. Here, the authors find atomic-scale polymorphic distortion and micrometer-scale high-density thin striped domains, which is key for high saturated poling. [ABSTRACT FROM AUTHOR]

Aim: Soil microbes can significantly influence restoration outcomes via interaction with plant community assembly processes, yet knowledge about variation in soil microbial communities – in particular functional variation – during oldfield succession is limited. Methods: We divided a well-dated successional chronosequence on the Tibetan Plateau into five stages: stage 1 (continued arable land), stage 2 (arable abandoned for 2 years), stage 3 (arable abandoned for 10 years), stage 4 (arable abandoned for 20 years), and natural grassland. We investigated the changes in taxonomic and functional composition of bacterial and fungal communities in these successional stages. Results: The richness of bacterial and fungal communities had a unimodal relationship with successional age, as the both were initially low and decreased again in natural grasslands. These changes were more correlated to soil properties. For both bacterial and fungal communities, taxonomic similarity to natural grasslands increased monotonously with successional age. The functional composition of bacterial communities shifted with successional age towards increased importance of strains involved in the C cycle rather than the N cycle, due to higher plant richness. For fungal communities, saprotrophs showed an increasing trend with successional age although low relative abundance in natural grasslands, which was regulated by belowground biomass. Symbiotrophs did not change during succession, but pathotrophic fungal relative abundance decreased rapidly after agricultural abandonment because of increased plant richness. Conclusions: Overall, twenty years of oldfield succession did not appear to restore richness of soil bacterial and fungal communities to the levels of natural grasslands. Community taxonomic and functional composition in successional stages up to 20 y old were also different from natural grasslands. Our results suggest more important role of plant community than microbial community to soil nutrient cycling during restoration in oldfields. [ABSTRACT FROM AUTHOR]

Ferroelectric polymer-based electrocaloric effect may lead to sustainable heat pumps and refrigeration owing to the large electrocaloric-induced entropy changes, flexible, lightweight and zero-global warming potential. Herein, low-k nanodiamonds are served as extrinsic dielectric fillers to fabricate polymeric nanocomposites for electrocaloric refrigeration. As low-k nanofillers are naturally polar-inactive, hence they have been widely applied for consolidate electrical stability in dielectrics. Interestingly, we observe that the nanodiamonds markedly enhances the electrocaloric effect in relaxor ferroelectrics. Compared with their high-k counterparts that have been extensively studied in the field of electrocaloric nanocomposites, the nanodiamonds introduces the highest volumetric electrocaloric enhancement (~23%/vol%). The resulting polymeric nanocomposite exhibits concurrently improved electrocaloric effect (160%), thermal conductivity (175%) and electrical stability (125%), which allow a fluid-solid coupling-based electrocaloric refrigerator to exhibit an improved coefficient of performance from 0.8 to 5.3 (660%) while maintaining high cooling power (over 240 W) at a temperature span of 10 K. Low-k nanodiamonds are discovered to possess the ability to concurrently enhance the electrocaloric effect, thermal conductivity, and electrical stability of polymeric nanocomposites, providing support for electrocaloric refrigeration. [ABSTRACT FROM AUTHOR]

Numerous studies have shown that teaching the history and philosophy of science (POS) can help improve senior high school students' scientific literacy. The history of science is usually taught in school science lessons by reference to particular cases, experiments, and scientists. In contrast, the POS — that is, the study of general and fundamental questions regarding the nature of science (NOS) — is often embedded within lessons, is considered difficult to teach, and is sometimes hidden from students. This research analyses the overlap between the conceptualisations of the NOS and the POS. The paper also reports on a study that used "explicit" pedagogical methods to teach topics related to the POS to Chinese senior high school students. The empirical results, which are supported by a theoretical framework that adopts the family resemblance approach to the NOS, show that students who participated in this POS course significantly improved their scientific literacy and their understanding of the relationships among science, technology, and society. The POS topics in this course helped students better understand the cognitive-epistemic system in the NOS. The findings of this small-scale study have broader implications for the way in which the POS is taught in high school education. [ABSTRACT FROM AUTHOR]

Slot filling, to extract entities for specific types of information (slot), is a vitally important modular of dialogue systems for automatic diagnosis. Doctor responses can be regarded as the weak supervision of patient queries. In this way, a large amount of weakly labeled data can be obtained from unlabeled diagnosis dialogue, alleviating the problem of costly and time-consuming data annotation. However, weakly labeled data suffers from extremely noisy samples. To alleviate the problem, we propose a simple and effective Co-Weak-Teaching method. The method trains two slot filling models simultaneously. These two models learn from two different weakly labeled data, ensuring learning from two aspects. Then, one model utilizes selected weakly labeled data generated by the other, iteratively. The model, obtained by the Co-Weak-Teaching on weakly labeled data, can be directly tested on testing data or sequentially fine-tuned on a small amount of human-annotated data. Experimental results on these two settings illustrate the effectiveness of the method with an increase of 8.03% and 14.74% in micro and macro f1 scores, respectively. [ABSTRACT FROM AUTHOR]

Relaxor ferroelectrics are known for outstanding piezoelectric properties, finding a broad range of applications in advanced electromechanical devices. Decoding the origins of the enhanced properties, however, have long been complicated by the heterogeneous local structures. Here, we employ the advanced big-box refinement method by fitting neutron-, X-ray-based total scattering, and X-ray absorption spectrum simultaneously, to extract local atomic polar displacements and construct 3D polar configurations in the classical relaxor ferroelectric Pb(Mg1/3Nb2/3)O3–PbTiO3. Our results demonstrate that prevailing order-disorder character accompanied by the continuous rotation of local polar displacements commands the composition-driven global structure evolution. The omnidirectional local polar disordering appears as an indication of macroscopic relaxor characteristics. Combined with phase-field simulations, it demonstrates that the competing local polar order-disorder between different states with balanced local polar length and direction randomness leads to a flattening free-energy profile over a wide polar length, thus giving rise to high piezoelectricity. Our work clarifies that the critical structural feature required for high piezoelectricity is the competition states of local polar rather than relaxor. Understanding high piezoelectricity in relaxors is challenging due to the heterogeneous structures. Here, the authors demonstrate that the competing local polar order-disorder state with balanced length and direction randomness is the key. [ABSTRACT FROM AUTHOR]

Longitudinal studies of correlated cognitive and disability outcomes among older adults are characterized by missing data due to death or loss to follow-up from deteriorating health conditions. The Mini-Mental State Examination (MMSE) score for assessing cognitive function ranges from a minimum of 0 (floor) to a maximum of 30 (ceiling). To study the risk factors of cognitive function and functional disability, we propose a shared parameter model to handle missingness, correlation between outcomes, and the floor and ceiling effects of the MMSE measurements. The shared random effects in the proposed model handle missingness (either missing at random or missing not at random) and correlation between these outcomes, while the Tobit distribution handles the floor and ceiling effects of the MMSE measurements. We used data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) and a simulation study. By ignoring the MMSE floor and ceiling effects in the analyses of the CLHLS, the association of systolic blood pressure with cognitive function was not significant and the association of age with cognitive function was lower by 16.6% (from −6.237 to −5.201). By ignoring the MMSE floor and ceiling effects in the simulation study, the relative bias in the estimated association of female gender with cognitive function was 43 times higher (from −0.01 to −0.44). The estimated associations obtained with data missing at random were smaller than those with data missing not at random, demonstrating how the missing data mechanism affects the analytic results. Our work underscores the importance of proper model specification in longitudinal analysis of correlated outcomes subject to missingness and bounded values. [ABSTRACT FROM AUTHOR]

The ferroelectric chiral vortex domains are highly desirable for the application of data storage devices with low-energy consumption and high-density integration. However, the controllable switching of vortex chirality remains a challenge in the current ferroelectric community. Utilizing phase-field simulations, we investigate the vortex domain evolution and chirality formation in BiFeO3 thin films. By applying local surface charge or electric field, we demonstrate that the vorticity and the polarity can be manipulated by the initial bi-domain arrangement and the external field with different directions, respectively. By exchanging the domain arrangements, the opposite chirality can be obtained. Importantly, the topological vortex domain is retained after removing the external field. The vortex chirality can be switched reversibly with high reproducibility, which is beneficial to fatigue tolerance of the material in the operation. These results provide theoretical guidance for manipulating the vortex chirality in ferroelectric films. [ABSTRACT FROM AUTHOR]

Hybrid superconductor-ferromagnet materials have gained huge attention due to their opposite nature of electronic states, bringing up new properties and applications when coupled together. Cryogenic sensors and memories research significantly lag behind their conventional counterparts. Here, we investigated numerically the strain/motion sensing ability of superconductor-ferromagnet bilayer using Ginzburg–Landau equations for superconductivity and Landau-Lifshitz-Gilbert equations for ferromagnetism. Clear segregation of average carrier concentration of the superconductor layer, which defines its conductivity, was observed with various magnitudes of strain (i.e. 0%, 1%, and 5%). The current purge was used to bring the designed sensor to its ground state, whereas the sensor retained the information on the amount of strain for the extended period unless reset (by the current purge) for reuse. This work opens up a new direction for superconductor-ferromagnet bilayer device applications towards strain/motion sensors and/or transducers. [ABSTRACT FROM AUTHOR]

More than a decade of research on the electrocaloric (EC) effect has resulted in EC materials and EC multilayer chips that satisfy a minimum EC temperature change of 5 K required for caloric heat pumps1–3. However, these EC temperature changes are generated through the application of high electric fields4–8 (close to their dielectric breakdown strengths), which result in rapid degradation and fatigue of EC performance. Here we report a class of EC polymer that exhibits an EC entropy change of 37.5 J kg−1 K−1 and a temperature change of 7.5 K under 50 MV m−1, a 275% enhancement over the state-of-the-art EC polymers under the same field strength. We show that converting a small number of the chlorofluoroethylene groups in poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) terpolymer into covalent double bonds markedly increases the number of the polar entities and enhances the polar–nonpolar interfacial areas of the polymer. The polar phases in the polymer adopt a loosely correlated, high-entropy state with a low energy barrier for electric-field-induced switching. The polymer maintains performance for more than one million cycles at the low fields necessary for practical EC cooling applications, suggesting that this strategy may yield materials suitable for use in caloric heat pumps.A study reports and characterizes a high-entropy electrocaloric polymer that switches under low fields, and discusses its potential suitability for use in caloric heat pumps. [ABSTRACT FROM AUTHOR]

Adopting an explicit and reflective approach to the teaching of the history and philosophy of science is useful in promoting high school students' understanding of the nature of science. Whereas the history of science is usually signposted clearly in the school science curriculum, the philosophy of science is considered to be embedded in and integral to science education. This article argues that philosophical topics also need to be explicitly signposted and discussed in the teaching of the nature of science in high schools. This study investigates an interdisciplinary course on the nature of science in a Chinese senior high school. The course involved explicit teaching of philosophy of science topics with subject knowledge in each lesson. This mixed method design of the research included a modified version of the Views on Science, Technology and Society questionnaire as reported by Aikenhead and Ryan (Science Education, 76(5):477‑491, 1992) and phenomenographical analysis. Although the sample size is small, the results suggest that explicit teaching of philosophy of science topics helps students better understand both the nature of science and the relationship between science, technology and society. [ABSTRACT FROM AUTHOR]

Deformation-induced martensitic transformations (DIMTs) have been widely observed in iron and ferroalloys under various mechanical loading conditions, thereby showing extreme scientific merits and engineering significance. Since deformations and fractures affect one another and reflect the relative movements of atoms, DIMTs often accompany fractures. In this work, molecular dynamics simulation was performed with a (010) [100] pre-cracked model to study DIMTs from an α-Fe single crystal during the mode-I fracture process. The observed DIMTs were verified using first-principle calculations. A crack tip tracking algorithm by scanning the nearby atoms is proposed, and the obtained critical stress intensity factor was proved to be close to the experimental results. Quasi-cleavage fracture happened with the nucleation and growth of the γ (fcc) phase, which was transformed by activating the {121} 111 and {110} 111 shears near the crack tip. The layered ε (hcp) phase was formed by stacking faults inside the γ phase and was unstable by driving force analysis. [ABSTRACT FROM AUTHOR]

Background: The pediatric patient's response to hemorrhage as a function of young age is not well understood. As a result, there is no consensus on optimal resuscitation strategies for hemorrhagic shock in pediatric patients, or on the identification of clinical triggers to prompt implementation. The study objective was to develop a model of pediatric hemorrhage using young pigs to simulate school-aged children, and determine clinical and laboratory indicators for significant hemorrhage.Materials and Methods: 29 non-splenectomized female pigs, aged 3 months, weighing 30-40 kg, were randomized into groups with varying degrees of hemorrhage. Bleeding occurred intermittently over 5 h while the animals were anesthetized but spontaneously breathing. Various physiologic and biochemical markers were used to monitor the piglets during hemorrhage.Results: Swine experiencing up to 50% hemorrhage survived without exception throughout the course of hemorrhage. 80% (4/5) of the animals in the 60% hemorrhage group survived. Need for respiratory support was universal when blood loss reached 50% of estimated blood volume. Blood pressure was not useful in classifying the degree of shock. Heart rate was helpful in differentiating between the extremes of blood loss examined. Arterial pCO2, pH, lactate, HCO3 and creatinine levels, as well as urine output, changed significantly with increasing blood loss.Conclusions: Young swine are resilient against hemorrhage, although hemorrhage of 50% or greater universally require respiratory support. In this animal model, with the exception of heart rate, vital signs were minimally helpful in identification of shock. However, change in select laboratory values from baseline was significant with increasing blood loss.Level Of Evidence: This was a level II prospective comparative study. [ABSTRACT FROM AUTHOR]

Objectives: To explore associations of dietary diversity with cognitive function among Chinese elderly. Design: This cross-sectional study was conducted in 2011-2012, data were analyzed using multiple linear regression and logistic regression models. Setting: community-based setting in the 23 provinces in China. Subjects: 8,571 elderly participants, including 2984 younger elderly aged 65-79 and 5587 oldest old aged 80+ participated in this study. Measurement: Intake frequencies of food groups was collected and dietary diversity (DD) was assessed based on the mean of DD score. Cognitive function was assessed using the Chinese version of Mini-Mental State Examination (MMSE), and cognitive impairment was defined using education-based cutoffs. Information about socio-demographics, lifestyles, resilience and health status was also collected. Results: Poor dietary diversity was significantly associated with cognitive function, with β (95% CI) of -0.11(-0.14, -0.08) for - log (31-MMSE score) and odds ratio (95% CI) of 1.29 (1.14, 1.47) for cognitive impairment. Interaction effect of age with DD was observed on cognitive impairment (P interaction=0.018), but not on-log (31-MMSE score) (P interaction=0.08). Further separate analysis showed that poor DD was significantly associated with increased risk of cognitive impairment in the oldest old (p<0.01), with odds ratio (95% CI) of 1.34 (1.17, 1.54), while not in the younger elderly (p>0.05), with OR (95% CI) being 1.09 (0.80, 1.47) in the fully adjusted model. Similar results were obtained when DD was categorized into four groups. Conclusions: Poor dietary diversity was associated with worse global cognitive function among Chinese elderly, and particularly for the oldest old. This finding would be very meaningful for prevention of cognitive impairment. [ABSTRACT FROM AUTHOR]

Letter to the Editor [ABSTRACT FROM AUTHOR]

Correction to: I Nature Communications i https://doi.org/10.1038/s41467-022-34062-6, published online 25 October 2022 In this article the affiliation 'Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore'. for Jie Yin should be removed. The affiliation 'Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore' for Kui Yao should read "Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), Singapore 138634, Singapore". [Extracted from the article]

Objectives: The association between cognitive function and cholesterol levels is poorly understood and inconsistent results exist among the elderly. The purpose of this study is to investigate the association of cholesterol level with cognitive performance among Chinese elderly. Design: A cross-sectional study was implemented in 2012 and data were analyzed using generalized additive models, linear regression models and logistic regression models. Setting: Community-based setting in eight longevity areas in China. Subjects: A total of 2000 elderly aged 65 years and over (mean 85.8±12.0 years) participated in this study. Measurements: Total cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) concentration were determined and cognitive impairment was defined as Mini-Mental State Examination (MMSE) score≤23. Results: There was a significant positive linear association between TC, TG, LDL-C, HDL-C and MMSE score in linear regression models. Each 1 mmol/L increase in TC, TG, LDL-C and HDL-C corresponded to a decreased risk of cognitive impairment in logistic regression models. Compared with the lowest tertile, the highest tertile of TC, LDL-C and HDL-C had a lower risk of cognitive impairment. The adjusted odds ratios and 95% CI were 0.73(0.62-0.84) for TC, 0.81(0.70-0.94) for LDL-C and 0.81(0.70-0.94) for HDL-C. There was no gender difference in the protective effects of high TC and LDL-C levels on cognitive impairment. However, for high HDL-C levels the effect was only observed in women. High TC, LDL-C and HDL-C levels were associated with lower risk of cognitive impairment in the oldest old (aged 80 and older), but not in the younger elderly (aged 65 to 79 years). Conclusions: These findings suggest that cholesterol levels within the high normal range are associated with better cognitive performance in Chinese elderly, specifically in the oldest old. With further validation, low cholesterol may serve a clinical indicator of risk for cognitive impairment in the elderly. [ABSTRACT FROM AUTHOR]

In this work, a magnetically separable polypyrrole (PPy) modified FeO/ZnO composite photo-catalyst was synthesized and its photocatalytic activity was tested. The as-prepared FeO/ZnO/PPy nanocomposite was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectra. Furthermore, three different photocatalysts including the FeO/ZnO/PPy composite were tested using methyl orange (MO) degradation reaction under UV light irradiation. The relative results demonstrated that the FeO/ZnO/PPy composite has the highest photochemical activity after 4 h photocatalytic experiment. It can be easily separated using an external magnetic field. This kind of composite photocatalysts with easiness of separation can have potential applications in the treatment of water contaminated by organic pollutants. [ABSTRACT FROM AUTHOR]

It is known that aquaporin 5 (AQP5) may represent a novel therapeutic target for treating colon cancer (CC), but whether AQP5 plays a role in the regulation of multidrug resistance (MDR) of colon cancer still remains unclear. In the present study, AQP5 and P-glycoprotein (P-gp), glutathione S-transferase-π (GST-π), topoisomerase II (TOPO II), and thymidylate synthase (TS) were checked in CC and adjacent cancer tissues; AQP5-siRNA was applied to silencing AQP5 in CC cell line HT-29, 5-fluorouracil (5-FU), and cisplatin (DDP) added on cells, and sulforhodamine B (SRB) was used; fluorescence real-time quantitative RT-PCR and Western blot were employed to detect changes in multidrug resistance factor and expression mitogen-activated protein kinase (MAPK) signaling pathway in HT-29. The results showed that AQP5 is significantly induced in cancer tissues than that in adjacent cancer tissues. The expression of AQP5 is positively correlated with drug resistance factors, as demonstrated by the increased expressions of P-gp, GST-π, and TOPO II in CC tissues compared to that in adjacent cancer tissues. Conversely, knockdown of AQP5 in HT-29 human colon cancer cells increased inhibition rates of cancer chemotherapeutic drugs such as 5-FU and DDP. The improved efficacies of chemotherapeutic drugs are associated with the decreased expression of P-gp, GST-π, and TOPO II. In addition, phosphorylation of p38 MAPK was increased by knockdown of AQP5 in HT-29 cells while phosphorylation and expression of extracellular signal-regulated kinase (ERK), c-jun N-terminal kinase (JNK), and Protein kinase B (AKT) were not affected. P38 MAPK inhibitor increased the drug sensitivity of HT-29 cells in a similar way as AQP5-siRNAs do. So these results indicate that AQP5 is associated with drug resistance of colon cancer, and that the AQP5-P38 MAPK pathway may represent a potential drug target to improve drug resistance of colon cancer cells. [ABSTRACT FROM AUTHOR]

C-reactive protein (CRP), an inflammatory marker that statistically predicts future cardiovascular risk, has been reported to be associated with plasma lipid level changes. Whether CRP genetic variants affect lipid metabolism is of importance to investigate. A community-based study population including 2,731 adult subjects aged 18-62 years was used to evaluate the association of CRP gene with dyslipidemia and five tagging SNPs (tagSNPs) were genotyped. Multiple logistic regression was applied to further evaluate relationships between the SNPs and lipid metabolism abnormality and general linear model was applied to compare plasma lipid levels between genotypes. Association analyses indicated that recessive model of SNPs rs876537 and rs4285692 had significant association with elevated HDL after adjustment for covariates. Odds ratio (OR) of rs876537 were 0.60 for HDL > 1.54 versus 1.04-1.54 mmol/L ( P = 0.011), as well as, ORs were 0.617 for HDL > 1.83 versus ≤1.35 mmol/L ( P = 0.002) and 0.724 for HDL = 1.59-1.83 versus ≤1.35 mmol/L ( P = 0.028) respectively. OR of rs4285692 was 0.634 for HDL > 1.83 versus ≤1.35 mmol/L ( P = 0.027). Further stratification analysis found significant associations of rs10737175 with elevated HDL (>1.54 vs. 1.04-1.54 mmol/L, OR 0.629 and P = 0.027) and elevated TG (≥1.70 vs. <1.70 mmol/L, ORs of additive and dominant models were 0.628, 0.545 and P values were 0.006, 0.003 respectively) in female. rs4285692 was significantly associated with elevated LDL (≥3.37 vs. <3.37 mmol/L), ORs equaled to 1.532, 2.281 for additive model and recessive model and P values were 0.028, 0.024 respectively in male. Furthermore, quantitative trait analysis indicated the variation T to C of rs876537 significantly affect decreased plasma HDL level ( P = 0.014). Our findings suggest that CRP genetic polymorphisms independently had positive association with the risk of HDL, LDL and TG elevating and further replication in other large population and biological function research would be warranted. [ABSTRACT FROM AUTHOR]

The paper analyses the effects of intra-channel four-wave mixing (IFWM) on the high-speed optical fiber communication system. A new code format is developed with double 0 and double π phase separating 1 code; it can decrease the transmission penalty from fiber nonlinearity by counteracting the perturbation terms of IFWM. From the simulation of transmission of two classic code data “11011” and “11100”, we find that our proposed code format has a better suppression effect than the alternative modulation inversion (AMI) or the normal RZ format and supports a wider pulse mode. In a 40 Gbps system, the AMI format is 2 dB less than the RZ format, and our proposed format is 1 dB less than the AMI format when a 1 dB eye open penalty is taken as a metewand. Moreover, it can be realized as easily as the AMI format. [ABSTRACT FROM AUTHOR]

We analyzed the activities of specific enzymes, esterase and peroxidase, and the electrophoresis profiling of isozymes of both the second-generation (M1) and the third-generation (M2) individuals of Arabidopsis thaliana after the parental generation was treated with low-energy N+ implantation and γ-radiation. Results indicated that the mutagenic effects of both treatments were inheritable. The obvious difference between N+ implantation and γ-radial on the relationship of doses and effects was also observed. For the correlation between effects and doses, the former presented a particular saddle-like pattern, while the latter showed a pattern of linearity. Random amplification of polymorphic DNA analysis showed that the variant DNA bands were consistent in M1 and M2 generations treated with both γ-radiation and ion implantation. However, the ratio of individual plant variation between the two treatments was remarkably different. [ABSTRACT FROM AUTHOR]