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The electrocaloric effect (ECE), known for its environmentally friendly characteristics, holds significant promise for advancing next-generation solid-state refrigeration technologies. Achieving a large ECE along with a wide working temperature range near room temperature remains a key developmental goal. In this study, we successfully obtained a substantial ECE of 1.78 K and an extensive working temperature range of 103 K (ΔT > 1.52 K) near room temperature in CaZrO3-modified BaTiO3 lead-free ferroelectric ceramics. Furthermore, this achievement was verified using direct methods. The piezoresponse force microscopy (PFM) results suggest that the broad temperature range is attributed to the formation of ferroelectric microdomains and polar nanoregions (PNRs). Furthermore, X-ray photoelectron spectroscopy (XPS) and ultraviolet‒visible (UV‒Vis) spectroscopy reveal a decrease in the oxygen vacancy concentration and an increase in the bandgap for higher CaZrO3 doping levels. These changes synergistically enhance the maximum applied electric field, helping to achieve a high-performance ECE near room temperature. This research presents a straightforward and effective approach for achieving high-performance ECEs in BaTiO3 lead-free ceramics, offering promising prospects for application in next-generation solid-state refrigeration technologies.

Abstract With an increasing demand for environmentally friendly refrigeration, the solid‐state refrigeration based on the electrocaloric effect (ECE) has been drawn extensive attention. It is a challenge to maintain a large adiabatic temperature change (∆T) over a broad temperature span. Herein, the authors designed and synthesised (0.74‐x) Na0.5Bi0.5TiO3‐0.06BaTiO3‐0.2SrTiO3‐xBi(Mg0.5Zr0.5)O3 (abbreviated as NBT‐xBMZ) (x = 0, 0.02, 0.04, 0.06 and 0.08) lead‐free relaxor ferroelectrics. Their microstructures, dielectric properties, ferroelectric properties, ECEs and the structure‐property relationships were investigated. Via doping with BMZ, an enhanced relaxor feature and a wider temperature range where multi‐phases coexist were achieved. The relaxor ferroelectric characteristics were illustrated using the Vogel‐Fulcher relation. The indirectly calculated ECE results showed that the optimal ΔT of 1.11 K was obtained for the x = 0.02 sample at 90°C and 70 kV/cm over a wide Tspan of 120°C, providing a potential ECE material. The direct ECE results procured using thermocouple indicated that the maximal ∆T of 2.14 K and ∆T/∆E of 0.31 K m/MV were achieved in the same sample at 70°C and 7 MV/m and the variation trend of ECE results was consistent with the indirect results. Moreover, the multi‐phases coexistent strategy can be extended to other materials system to generate a large ΔT over a wide temperature range.

Abstract Solid-state cooling technology based on electrocaloric effect (ECE) has been advanced as an alternative to replace the vapour-compression approach to overcome the releasing of the global warming gases. However, the development in high ECE materials is still a challenge. In this work, polarization merging strategy was proposed to achieve a large ECE in xBa(Sn0.07Ti0.93)O3-(1−x)Ba(Hf0.1Ti0.9)O3 ferroelectric ceramics, where x = 0, 0.2, 0.4, 0.6, 0.8, and 1. Ba(Sn0.07Ti0.93)O3 with an orthorhombic phase and Ba(Hf0.1Ti0.9)O3 with a rhombohedral phase at room temperature were prepared beforehand as precursors, and phase-coexisted xBSnT-(1−x)BHfT ceramics were formed via a solid-state reaction approach. Phase coexisting structures were confirmed using the X-ray diffraction. The merged polarization was confirmed by the dielectric and ferroelectric properties. Optimal ECEs were obtained for 0.2BSnT-0.8BHfT ceramics, i.e., adiabatic temperature change ΔT = 2.16±0.08 K at 80 °C and 5 MV/m, and ΔT = 3.35±0.09 K at 80 °C and 7 MV/m.

Abstract Grid management is a grassroots governance strategy widely implemented in China since 2004 to improve the government’s efficiency to actively find and solve problems among populated regions. A grid-based strategy surveillancing high-risk groups, including mobile and migrant populations (MMPs), in the China–Myanmar border region has played an indispensable role in promoting and consolidating the malaria elimination efforts by tracking and timely identification of potential importation or re-establishment of malaria among MMPs. A sequential mixed methods was implementated to explore the operational mechanism and best practices of the grid-based strategy including through the focus group discussions (FGDs), comparison of before and after the implementation of a grid-based strategy in the field sites, and data collection from the local health system.This paper distills the implementation mechanism and highlights the role of the grid-based strategy in the elimination and prevention of re-establishment of malaria transmission.

Abstract Background Mosquito-based arbovirus surveillance can serve as an early warning in evaluating the status of mosquito-borne virus prevalence and thus prevent local outbreaks. Although Tengchong County in Yunnan Province—which borders Myanmar—is abundant and diverse in mosquitoes, very few mosquito-based arbovirus investigations have been conducted in the recent decade. Herein, this study aims to evaluate the presence and the diffusion of mosquito-borne pathogens, currently prevalent in this region. Methods We collected 9486 mosquitoes, representing eight species, with Culex tritaeniorhynchus and Anopheles sinensis as the dominant species, during high mosquito activity seasons (July–October) in Tengchong, in 2018. Samples collected from 342 pools were tested using reverse-transcription PCR to determine the species, distribution, and infection rates of virus and parasite, and further analyze their genotypes, phylogenetic relationships, infection rate, and potential pathogenicity. Results Fifteen Japanese encephalitis virus (JEV) strains from Cx. tritaeniorhynchus pools were detected. Seven strains of insect-specific flaviviruses (ISFVs), including two Aedes flavivirus (AeFV) and Yunnan Culex flavivirus strains each, one Culex theileri flavivirus, Yamadai flavivirus (YDFV) and Anopheles-associated flavivirus (AAFV) strains each were detected in Aedes albopictus, Cx. tritaeniorhynchus, Cx. vagans, Cx. pseudovihnui, and An. sinensis pools, respectively. The whole-genome was successfully amplified in one strain of JEV and AeFV each. Phylogenetic analysis using the E gene placed all the newly detected JEV strains into the GI-b genotype. They showed highly nucleotide identities, and were most closely related to the strain detected in Tengchong in 2010. The comparison of the E protein of JEV strains and vaccine-derived strain, showed six amino residue differences. The bias-corrected maximum likelihood estimation values (and 95% confidence interval) for JEV in Cx. tritaeniorhynchus collected in Tengchong in 2018 were 2.4 (1.4–3.9). Conclusions A potential Japanese encephalitis epidemic focus with the abundance of host mosquitoes and high JEV infection rate was observed in Tengchong. In addition, at least five species of ISFVs co-circulate in this area. This study highlights the importance of widespread and sustained mosquito-based arbovirus surveillance in local areas to prevent the transmission of JEV, and other emerging/re-emerging mosquito-borne pathogens. Graphic Abstract

The effect of a N,N-dimethylformamide (DMF)/acetone solvent system (3:7, 4:6, 5:5, 6:4, 7:3) and spinning medium (air and water) on the membrane morphology and the structure-property relationship were investigated. A facile method was optimized to generate a porous, polymer-fiber membrane via the combinative effect of electrospinning and thermally inducing phase separation of the DMF/acetone (4:6) solvent system in a water medium. The attenuated total reflection (ATR) - Fourier transform infrared (FTIR) results showed an increased β-phase compared to the pristine poly(vinylidene fluoride) (PVDF). The XRD and DSC results further confirmed that the co-existing α- and β-phases in the pristine PVDF were converted into a unique β-phase in the electrospun membranes. In addition, the solvent uptake percentage of the DMF/acetone (4:6) solvent system in a water medium (540) is much greater than that in an air medium (320), and over two times better than that of commercial polyethylene (PE) membranes (190). Similarly, the discharge capacity of the PVDF membrane separator prepared with the DMF/acetone (4:6) solvent system in a water medium is higher than that of the air medium. This enhancement of solvent uptake might be due to the interconnected porous morphology present in the water medium.

0.9KNbO3-0.1BaTiO3 ceramics, with a bimodal grain size distribution and typical tetragonal perovskite structure at room temperature, were prepared by using an induced abnormal grain growth (IAGG) method at a relatively low sintering temperature. In this bimodal grain size distribution structure, the extra-large grains (~10–50 μm) were evolved from the micron-sized filler powders, and the fine grains (~0.05–0.35 μm) were derived from the sol precursor matrix. The 0.9KNbO3-0.1BaTiO3 ceramics exhibit relaxor-like behavior with a diffused phase transition near room temperature, as confirmed by the presence of the polar nanodomain regions revealed through high resolution transmission electron microscope analyses. A large room-temperature electrocaloric effect (ECE) was observed, with an adiabatic temperature drop (ΔT) of 1.5 K, an isothermal entropy change (ΔS) of 2.48 J·kg−1·K−1, and high ECE strengths of |ΔT/ΔE| = 1.50 × 10−6 K·m·V−1 and ΔS/ΔE = 2.48 × 10−6 J·m·kg−1·K−1·V−1 (directly measured at E = 1.0 MV·m−1). These greatly enhanced ECEs demonstrate that our simple IAGG method is highly appreciated for synthesizing high-performance electrocaloric materials for efficient cooling devices.

PbxSr1-xTiO3 (x = 0.30, 0.35, 0.40, 0.45, 0.50 and 0.55) ceramics were fabricated by a solid-state reaction route. X–ray diffraction data at room temperature show PST samples shift from cubic to tetragonal phase with the increase of Pb2+ content. The microstructures were observed by scanning electron microscopy. Dielectric measurement was employed to investigate the ferroelectric–paraelectric phase transition behavior. Temperature dependent polarization–electric field hysteresis loops were conducted to study the electrocaloric effect (ECE) of the ferroelectric ceramics by indirect methods over a wide temperature range. Direct measurement of temperature change (ΔT) at room temperature for all samples can achieve 0.79–1.86 K. What's more, a giant ECE (ΔT = 2.05 K, EC strength (ΔT/ΔE) = 0.51 × 10−6 K m/V, under 40 kV/cm) was obtained in the sample of x = 0.35 near phase transition temperature. Our results suggest that the ceramics are promising cooling materials with excellent EC properties for energy related applications. Keywords: PbxSr1-xTiO3 ceramics, Electrocaloric effect, Phase transition, Energy applications

Abstract Background Many tick species have great morphological similarity and are thus grouped into species complexes. Molecular methods are therefore useful in the classification and identification of ticks. However, little is known about the genetic diversity of hard ticks in China, especially at the subspecies level. Tengchong is one of the epidemic foci of tick-borne diseases in China, but the tick species inhabiting the local area are still unknown. Methods Eighteen villages in Tengchong County, China, were selected for sampling carried out from September to October 2014. Infesting hard ticks were removed from the body surface of domestic animals and questing ticks were collected from grazing fields. After morphological identification, molecular characteristics of each tick species were analyzed based on both 16S rRNA and cytochrome c oxidase subunit 1 (cox1) gene fragments. Results Six tick species were identified based on morphology: Rhipicephalus microplus, R. haemaphysaloides, Ixodes ovatus, Haemaphysalis longicornis, H. shimoga and H. kitaokai. Phylogenetic analysis using the cox1 gene revealed that R. microplus ticks from the present study belong to clade C. For tick samples of both R. haemaphysaloides and I. ovatus, three phylogenetic groups were recognized, and the intergroup genetic distances exceeded the usual tick species boundaries. Haemaphysalis longicornis ticks were clustered into two separate clades based on the cox1 gene. For ticks from both H. shimoga and H. kitaokai, two phylogenetic groups were recognized based on the phylogenetic analysis of the 16S rRNA gene, and the intergroup genetic distances also exceeded the known boundaries for closely related tick species. Conclusions According to molecular analyses, new species or subspecies closely related to R. haemaphysaloides, I. ovatus, H. shimoga and H. kitaokai probably exist in the China-Myanmar border Tengchong County, or these ticks form species complexes with highly divergent mitochondrial lineages. Morphological comparisons are warranted to further confirm the taxonomic status of these tick species.

A negative electrocaloric effect (ECE) in B-site non-stoichiometric (Pb0.97La0.02)(Zr0.95Ti0.05)O3 antiferroelectric ceramics synthesized by the conventional solid-state reaction method is investigated via indirect and direct measurements. Temperature-dependent P-E hysteresis loops were measured. A giant negative electrocaloric temperature change of about 12.45 K was achieved. The results indicate that the antiferroelectric ceramics with non-stoichiometry modification could be a promising candidate for the applications in cooling devices. IMPACT STATEMENT Giant negative electrocaloric effect (NECE) was achieved in B-site non-stoichiometric PLZT2/95/5 ceramics, the NECE parameters are comparable or even larger than most of the reported bulk materials, making it attractive for cooling devices application.

Electrocaloric properties of [110] and [111] oriented 0.73Pb(Mg1/3Nb2/3)O3-0.27PbTiO3 single crystals were studied in the temperature range of 293–423 K. The Maxwell relations and the Landau–Ginsburg–Devonshire (LGD) phenomenological theory were employed as the indirect method to calculate the electrocaloric properties, while a high-resolution calorimeter was used to measure the adiabatic temperature change of the electrocaloric effect (ECE) directly. The results indicate that the directly measured temperature changes of ΔT > 2.5 K at room temperature were procured when the applied electric field was reversed from 1 MV/m to −1 MV/m, which are larger than those deduced pursuant to the Maxwell relation, and even larger than those calculated using the LGD theory in the temperature range of 293–~380 K.

The electrocaloric effect (ECE) in lead-free BaSnxTi1−xO3 (BSnT, x=0.05, 0.10 and 0.15) ceramics were investigated using a direct ECE measurement. Results indicate that the maximum ECE occurs near the Curie temperature and it slightly shifts towards high temperatures. The directly measured ECE is larger than that calculated using the Maxwell relation and P-E loops. A maximum electrocaloric efficiency ΔT∕ΔE=0.49×10−6KmV−1 was procured for the composition with x=0.15 at T=299.2K. And it also shows a broad peak in the temperature range of 250–320K.

Understanding the relationship between the timing of N fertilizer applications and crop primary production is crucial for achieving high yield and N use efficiency in agriculture. This study investigated the effects of starting-N plus topdressing N applications (as compared to the common practice of all basal application) on soybean photosynthetic capacity under different planting densities. A field experiment was conducted in two growing seasons (2011 and 2012), and the soybean (Glycine max L. Merrill) cultivar was Dongnong 52, three planting densities (20, 25 and 30 plants m−2), and four N fertilizer application patterns (all N fertilizer of 6 g N m−2 as basal fertilizer, all N fertilizer as topdressing at beginning pod stage (R3), 1.8 g N m−2 as basal fertilizer and 4.2 g N m−2 as topdressing at stage R3 and full pod stage (R4), respectively). The results indicated that under the same planting density, compared to applying all N as basal fertilizer, the application of starter-N plus topdressing N substantially reduced the rate of pod abscission, and enhanced leaf area index (LAI) significantly at beginning seed stage (R5) (P

Oil spilling has been a serious problem in the world for a long time, which can bring toxic substances to marine life. A large number of researchers around the world have introduced many measures to address this problem. One of the effective methods to remove oil from the oil/water mixture is to absorb oil from the mixture. Here, we prepared porous poly(lactic acid) (PLA) membranes using the electrospinning approach with different sized syringe needles, and used these membranes to absorb oil from the top of the water. It was found that the diameter of the needle has a big impact on the size and structure of the pores on the PLA fibers. The oil absorption capacity of membranes increases with a decreasing needle diameter due to the increased pore volume and specific surface area. The highest absorption capacity reached was 42.38 g/g for vacuum pump oil, 28.17 g/g for peanut oil, and 6.74 g/g for diesel oil.

A plot experiment including four treatments, CK (N 105 kg ha−1 as urea, including a basal N application of 35 kg ha−1 and a topdressing N 70 kg ha−1 at turned green stage) and optimized N management (OPT1, OPT2 and OPT3, applied two-thirds, one-third and two-fifths N at jointing stage, respectively, total N 60 kg ha−1), was conducted to evaluate the effects of nitrogen management on growth and N uptake of winter wheat (Triticum aestivum), Dongnong 1, which is the first highly cold tolerant winter wheat in China. Index of population quality, N uptake and yield were determined. The ear-bearing tiller rate was increased by above 12%, and the leaf area index, biomass and N uptake were significantly decreased (P

Babesiosis is a tick-borne, zoonotic disease caused by Babesia spp. Two cases of babesiosis were detected by nested polymerase chain reaction (PCR) in Yunnan province, China, and further confirmed by molecular assay. The blood smears showed intraerythrocytic ring form and tetrads typical of small B. microti. In both cases, the rapid diagnostic test (RDT) ruled out the possibility of co-infections with malaria. Neither case was initially diagnosed because of the low Babesia parasitemia. These two cases of babesiosis in areas along the Myanmar–China border pose the question of the emergence of this under recognized infection in countries or areas where malaria is endemic.[Figure: see text]

AIM: To evaluate the efficacy of prophylactic vitrectomy for acute retinal necrosis syndrome(ARNS).METHODS: Twenty-six patients(33 eyes)were retrospectively included in this study. The eyes were divided into 2 groups by treatment, including routine treatment, which consisted of antiviral medication and vitrectomy after retinal detachment(RD)(n=20), and prophylactic vitrectomy, which consisted of antiviral medication and vitrectomy for the prevention of RD performed during the active inflammatory phase(n=13). The follow-up period ranged from 6 to 48 months. RESULTS: In the routine treatment group, retinal detachment occurred in 11 eyes(55%), 4 eyes(20%)developed ocular atrophy, 3 eyes(15%)achieved increased visual acuity. In the prophylactic vitrectomy group, RD occurred in 1 eyes(8%), 5 eyes(38%)achieved increased visual acuity. There was lower incident of retinal detachment in the prophylactic vitrectomy group than that in the routine treatment group(PCONCLUSION: Prophylactic vitrectomy can prevent RD and improve the prognosis of ARNS.

(Pb1-xBax)(Zr0.95Ti0.05)O3 (x = 0, 0.025, 0.05, 0.075 and 0.1) ceramics were prepared via a solid-state reaction route. Low-frequency (20 ∼ 2 × 107 Hz) dielectric properties were investigated in the temperature region of 25-650 °C. Ba2+ doping can slightly reduce the phase transition temperature of ferroelectric to paraelectric. The dielectric diffuse anomaly in the dielectric relaxation was found in the high temperature region of 400-650 °C. Activation energy, calculated from the impedance and conductivity data of samples, suggests that the dielectric relaxation is due to oxygen vacancies generated during the sintering process. Ba2+ doping can reduce significantly the concentration of oxygen vacancies, and slightly enhance activation energy for the migration of oxygen vacancies. Results of activation energy calculated from impedance and conductance suggest that the dielectric relaxation is due to the short-range hopping of oxygen vacancies, and the conduction due to the movement of doubly-ionized oxygen vacancies.

Objective: To analyze the malaria epidemiological characteristics in Tengchong City from 2010 to 2015, so as to provide the evidence for adjusting and formulating measures in the elimination stage., Methods: The malaria data were collected and analyzed by using Microsoft Excel 2010 in Tengchong City from 2010 to 2015., Results: There were 1 408 malaria cases reported in Tengchong City from 2010 to 2015, including 1 091 cases of Plasmodium vivax infection, 256 cases of P. falciparum infection, 5 cases of P. malariae infection, 1 case of Plasmodium ovale infection, 1 case of mixed infections, and 54 unclassified cases. Totally 1 390 imported cases were recorded and 98.06% of them (1 363/1 390) were imported from Myanmar. Most of the patients ( n = 908) were aged from 21 to 40 years, and the male to female ratio was 11.03∶1. The highest-risk populations were farmers and migrant workers. The most cases were observed in April and June, and at that time, most of the floating workers returned., Conclusions: Imported malaria is severe in Tengchong City, and there is a great challenge to malaria elimination.

Objective: To study the prevalence of tick bites and relative factors of outpatients with fever from health care facilities in Tengchong County., Methods: From July to August, 2014, the outpatients with fever in five health care facilities namely Tengchong Center for Disease Control and Prevention, Hehua Health Center, Jietou Health Center, Qushi Health Center and Xinhua Health Center were investigated by questionnaires. The factors related to tick bites were explored with the univariate analysis and multiple regression models., Results: Totally 884 effect questionnaires were acquired. Among the 884 participants, 85 (9.6%) had experienced tick bites. The frequency of tick bites was associated with locations, gender, age group, ownership of cattle, working at foreign country, firewood cutting and lumbering in the forest (all P < 0.05). The multiple regression revealed that the male and people raising cattle, working at foreign country, engaging in firewood cutting and lumbering in the forest had a more risk for tick bites., Conclusions: Tick bites are common in the residents of Tengchong County. The risk of being bitten varies in different populations. The local health departments should promote health education in the high-risk population to reduce the risk of infecting tick-borne diseases.