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Climate-related disasters are increasing across the globe, but their adverse health impacts are unevenly distributed. The people most severely affected tend to be from socio-economically disadvantaged, vulnerable populations, who have high exposure to risk conditions and insufficient adaptive capacity. Despite the increasing health impacts of climate change and disaster risks felt in Asian countries such as China, Indonesia and Vietnam, there are few attempts to access and translate literature and evidence on climate-related disasters and adaptation activities from non-English speaking countries. Conducted by a multi-country project team, this review aims to better understand the current literature and to study gaps in these three countries through an extensive search of literature, in English, Chinese, Indonesian and Vietnamese. Through a systematic review process a total of 298 studies out of 10,139 were included in this study. Key findings confirm that all three countries have experienced increasing climate-related disasters with their associated health impacts, and that adaptation strategies are urgently needed to reduce the risk and vulnerability of the most affected populations. Future studies should consider conducting vulnerability assessments to inform translational research on developing effective adaptation strategies. Authors commented that a common challenge they found was the shortterm nature of disaster response mechanisms, and the lack of long-term investment and policy support for capacity building and multi-sectoral collaborative research that address the needs of populations vulnerable to climate-related disasters. Thus, to better prepare for future disasters, it is vital that governments and international agencies prioritize funding policies to fill this gap.

To the Editor: Because a healthy and efficient medical workforce is key to containing the present coronavirus disease 2019 pandemic, the protection of health care workers is paramount.1,2 According to the interim guidance for the pandemic from the World Health Organization,3 health care workers must don personal protective equipment (PPE) when testing a patient with a high suspicion of having pneumonia. Such PPE must include an N95 respirator, a pair of goggles or a face shield, a gown, and a pair of gloves.4 However, this set of PPE cannot cover all surfaces of the body. Thus, to minimize the risk of exposure to the pathogen, and to conserve PPE, we constructed a building-integrated sampling station. Designed by Tseng Yu-Chi and Tseng Kai-Chen, this station has a sealed acrylic window serving as a physical barrier separating the interior (where the physician is) from the exterior (where the patient is), and a pair of sealed rubber gloves affixed to the station for the physician to perform

Effect of initial martensite and tempered carbide characteristics on mechanical properties of 3Cr2MnNiMo mold steel were investigated. The results indicated that the initial martensite microstructure can be effectively adjusted by changing the quenching temperature. With the increase of quenching temperature from 760 °C to 1010 °C, the initial microstructure gradually changed from acicular ferrite + plate martensite + M7C3 carbides to lath martensite, and the grain size increased monotonically. The coarsening of the initial martensite led to the increase of tempered carbide size, and the morphology of tempered carbide gradually changed from spherical to long strip-shaped. The large-size and long strip-shaped carbides promoted the formation of micro-voids during the tensile deformation and significantly decreased the elongation. In addition, with the coarsening of the martensite microstructure, both the decrease of high-angle grain boundaries (HAGB) density and the appearance of long strip-shaped tempered carbides significantly reduced the impact absorbed energy. The fracture mechanism transformed from ductile fracture caused by micro-voids coalescence to intergranular cleavage fracture. Moreover, when the initial microstructure completely transformed into lath martensite, the yield and tensile strength remained approximately unchanged. The precipitation strengthening compensated the adverse effect of martensite coarsening.

Background Context Polymethylmethacrylate (PMMA) is widely used for pedicle screw augmentation in osteoporosis. Intriguingly, there have been no biomechanical comparisons of the stability of pedicle screws augmented with different volumes of PMMA or studies of the relationship between screw stability and volume of PMMA, especially in different degrees of osteoporosis. Purpose The purposes of the study reported here were to compare screw stability by different volumes of PMMA augmentation, to analyze the relationship between screw stability and PMMA volume, and to make a preliminary determination of the optimum volume of PMMA augmentation for different degrees of osteoporosis. Study Design This study is a biomechanical comparison of pedicle screws augmented with various volumes of PMMA in cadaveric lumbar vertebrae. Methods Thirty-six pedicles from 18 osteoporotic lumbar vertebrae were randomly divided into groups A0 through A5, and 36 pedicles from 18 severely osteoporotic lumbar vertebrae were randomly divided into groups B0 through B5. A different volume of PMMA was injected into each one of groups A0 through A5 (0, 0.5, 1.0, 1.5, 2.0, and 2.5 mL, respectively) and into each one of groups B0 through B5 (0, 1.0, 1.5, 2.0, 2.5, and 3.0 mL, respectively), and then pedicle screws were inserted in all vertebrae. After complete solidification of the PMMA, we examined pedicle X-rays, performed axial pullout tests, and determined the maximum axial pullout strength (F max ) for all samples. Results No PMMA was found around the screws in groups A0 and B0. In groups A1 to A5 and B1 to B5, screws were wrapped by gradually increasing amounts of PMMA. There was no PMMA leakage or screw malpositioning in any samples. The F max in groups A1 through A5 increased by 32.40%, 64.42%, 116.02%, 174.07%, and 207.42%, respectively, compared with that in group A0. There were no significant differences in F max between groups A0 and A1, A1 and A2, A2 and A3, A3 and A4, and A4 and A5 (p>.05), but there were significant differences in F max between any other two groups (p max in groups B1 through B5 increased by 23.48%, 48.40%, 106.60%, 134.73%, and 210.04%, respectively, compared with that in group B0. There were no significant differences in F max between groups B0 and B1, B0 and B2, B1 and B2, B2 and B3, B3 and B4 (p>.05), but there were significant differences in F max between any other two groups (p max and volume of PMMA in both osteoporotic and severely osteoporotic lumbar vertebrae (p Conclusions Polymethylmethacrylate can significantly enhance stability of pedicle screws in both osteoporotic and severely osteoporotic lumbar vertebrae. There is a significant positive correlation between screw stability and volume of PMMA. Within a certain range, nevertheless, increasing the volume of PMMA does not significantly improve screw stability. We suggest that 1.5 and 3 mL, respectively, are the volumes of injected PMMA that will optimize pedicle screw stability in osteoporotic and severely osteoporotic lumbar vertebrae.

There is no ideal implant for mechanical strut on early-stage osteonecrosis of the femoral head (ONFH) after core decompression. In this study, a biogenic trabecular porous titanium rod with lamellar configuration was designed and fabricated using selective laser melting technique. Early-stage ONFH of sheep induced by cryo-insult were dealt with core decompression combined with rod insertion (Rod group) and core decompression alone (CD group) after X-ray evaluation was used to assess the necrotic region one months after cryo-intervention. Bone integration and ingrowth of the two groups were investigated and compared. Early-stage ONFH intervened with the rod gained better bone ingrowth than CD 3 and 6 months after the intervention, as evidenced by radiographic, micro-CT and histological evaluation. X-ray images showed compact integration between rods and peripheral bone, evidenced by no radiolucent lines encircling the rods at 3 and 6 months. Micro-CT and histological images showed that the new bone had grown into the centre of rods along the metal at 3 months, whereas the new bone grew mainly at the periphery of the decompressive channel. Micro-CT analysis show that the ratios of bone volume to total volume (BV/TV) of volume of interest (VOI) in Rod group was 890.0% and 438.1% higher than CD group at 3 (0.198 ± 0.0094 VS 0.020 ± 0.0058, p 0.05, n = 3) and 6 (0.226 ± 0.0166 VS 0.042 ± 0.0061, p 0.05, n = 3) months respectively. Histological analysis showed that the BV/TV of VOI in Rod group was 881.0% and 413.3% higher than CD group at 3 (0.206 ± 0.0102 VS 0.021 ± 0.0061, p 0.05, n = 3) and 6 (0.231 ± 0.0156 VS 0.045 ± 0.0059, p 0.05, n = 3) months respectively. The mechanical tests revealed that the maximum load of Rod group was 57.6% larger than CD group at 6 months (4505.25 ± 443.86 N VS 2858.25 ± 512.91 N, p 0.05, n = 3). These favourable short-term results can provide insight on treatment of early-stage ONFH.

Motivated by the small lattice mismatch between ferrite and vanadium nitride (VN), we describe here the welding thermal cycle simulation that provides high toughness in the ICRCG HAZ of low carbon V–N steel. This unique behavior is attributed to the formation of ultra-fine grained ferrite along prior austenite grain boundaries generated by the first pass welding thermal cycle with high misorientation boundaries, where V(C, N) precipitates provide potential nucleation sites for ferrite, leading to extraordinary refinement of martensite/austenite (M/A) constituent. Nitrogen stimulates the precipitation behavior of V(C, N). The nucleation of high density of V(C, N) precipitates consumes carbon-content in the austenite, leading to decrease in the carbon-content in the M/A constituent, with consequent decrease in hardness. The increase in toughness is explained in terms of Griffith's crack propagation theory.

Controlled rolling followed by two-stage continuous cooling was carried out in-house to study the microstructure and mechanical properties of a low carbon microalloyed steel plate of medium thickness gauge. The objective of the study was to develop a process of obtaining excellent mechanical properties (strength, toughness, and ductility) in a microalloyed steel. The process is industrially viable because it does not require high degree of cooling and large reduction during thermo-mechanical processing. The study demonstrates that it is possible to obtain yield strength, tensile strength, elongation, and percentage reduction in area 585 MPa, 680 MPa, 29.5%, and 55%, respectively, with total deformation reduction of 50% and small first stage cooling rate. The total impact energy at −20 °C was 140 J. The microstructure consists of polygonal ferrite and acicular ferrite. The strain-induced 20–30 nm precipitates act as nucleation sites for acicular ferrite. The acicular ferrite contributes to high strength and good toughness, while polygonal ferrite provides excellent elongation.

For the purpose of obtaining the appropriate heat input in the simulated weld CGHAZ of the hot-rolled V–N microalloyed high strength S-lean steel, the microstructural evolution, hardness, and toughness subjected to four different heat inputs were investigated. The results indicate that the hardness decreases with increase in the heat input, while the toughness first increases and then decreases. Moderate heat input is optimum, and the microstructure is fine polygonal ferrite, granular bainite, and acicular ferrite with dispersive nano-scale V(C,N) precipitates. The hardness is well-matched with that of the base metal. Moreover, the occurrence of energy dissipating micromechanisms (ductile dimples, tear ridges) contributes to the maximum total impact energy. The detrimental effect of the free N atoms on the toughness can be partly remedied by optimizing the microstructural type, fraction, morphologies, and crystallographic characteristics. The potency of V(C,N) precipitates on intragranular ferrite nucleation without MnS assistance under different heat inputs was discussed.

Rodents usually exert important role, through their scatter seed hoarding behavior, on plant regeneration in the field. To investigate the effects of burial and insects infection on germination and seedling growth of acorns of Quercus variabilis, perfect and infected acorns were buried in the soil among four depths, 0 cm, 4 cm, 8 cm and 12 cm, to simulate the seed hoarding behavior by rodents in the field. The results showed that (1) the germination rate were both high, under 4 cm burial depth, for perfect and infected acorns (92% and 53% separately), and decreased significantly with increased burial depth; (2) perfect acorns germinated better in 4 cm burial depth group by autumn of first year; (3) there 32% (perfect) and 26% (infected) acorns with 0 cm burial depth, on the soil surface, germinated successfully; for infected acorns, the 4 cm depth group had the best germination or seedling recruitment in both the first year and the second year; (4) acorns of Q. variabilis exhibited dormancy period ca 7 months; (5) burial, infection, and the interaction between these two factors influenced several aspects including stem height, leaf weight, Tannic acid, and biomass within seedling growth; (6) the results from this study suggest that proper burial would be helpful for the germination and seedling growth, and seedlings of shallow buried acorns had an advantage in their early development; and (7) infection by insects will not inevitably influence seedling early development.

A Ti bearing interstitial free (IF) steel was finish rolled in the ferrite zone and the texture evolution during double cold rolling (DCR) and double annealing technology was investigated by orientation distribution function (ODF). The γ-fibre texture of DCR has been compared with traditional single cold rolling (SCR) and annealing. The SCR annealing texture component {1 1 1} 〈1 1 2〉 remained after DCR and it improves the formation of {1 1 1} 〈1 1 0〉 during DCR annealing. During rolling process the gliding planes will usually rotate towards rolling plane. The rotation could not be achieved totally due to the deforming resistance from crystal defects. The result is that {1 1 1} turn to parallel the sheet plane and form. The in-grain shear bands observed after DCR play a major role on the rotation and improve the γ-fibre texture indirectly. The mean plastic strain ratio ( r -value) of DCR is much higher than that of SCR. The work hardening coefficient ( n -value) less relies on the rolling and annealing technology.