Preparation, thermal storage properties and application of sodium acetate trihydrate/expanded graphite composite phase change materials.

The development of energy storage technology is beneficial for the efficient use of energy and sustainable development. As an effectual approach for storing and transporting thermal energy, latent heat storage using phase change materials (PCMs) has attracted tremendous attention. However, low thermal conductivity, poor stability, and leakages are considerable challenges to the widespread application of solid-liquid PCMs. Composite phase change materials (CPCMs) were prepared by combining expanded graphite (EG) and sodium acetate trihydrate (CH3COONa·3H2O, SAT). EG as a supporting material plays a crucial part in both enhancing the thermal conductivity and preventing the melted PCMs from leakage. The chemical structure, micromorphology, thermal stability, thermal conductivity, phase change behavior and heat storage performance of SAT/EG CPCMs have been extensively investigated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermal conductivity analysis, differential scanning calorimetry (DSC), and cycling stability measurement. The results of SEM indicate that EG with a loose and porous layered structure has a good molding effect and can adsorb SAT well. XRD and FTIR results show that only a simple physical combination between EG and SAT exists, and no new substances have been produced. Compared with pure SAT, thermal conductivity and supercooling tests show that the supercooling degree of the CPCMs was decreased and the thermal conductivity was increased by 205.1%. In addition, the addition of 2 wt% of disodium hydrogen phosphate dodecahydrate (Na2HPO4·12H2O, DHPD) as a nucleating agent and 0.5 wt% of gelatin as a thickening agent to SAT could reduce the supercooling degree and inhibit the phase separation well. Based on SAT/EG-8% CPCMs, an oven with phase change energy storage was designed and the heat storage/release performance of the oven was investigated under different operating conditions.

Uncovering and Experimental Realization of Multimodal 3D Topological Metamaterials for Low-Frequency and Multiband Elastic Wave Control.

Topological mechanical metamaterials unlock confined and robust elastic wave control. Recent breakthroughs have precipitated the development of 3D topological metamaterials, which facilitate extraordinary wave manipulation along 2D planar and layer-dependent waveguides. The 3D topological metamaterials studied thus far are constrained to function in single-frequency bandwidths that are typically in a high-frequency regime, and a comprehensive experimental investigation remains elusive. In this paper, these research gaps are addressed and the state of the art is advanced through the synthesis and experimental realization of a 3D topological metamaterial that exploits multimodal local resonance to enable low-frequency elastic wave control over multiple distinct frequency bands. The proposed metamaterial is geometrically configured to create multimodal local resonators whose frequency characteristics govern the emergence of four unique low-frequency topological states. Numerical simulations uncover how these topological states can be employed to achieve polarization-, frequency-, and layer-dependent wave manipulation in 3D structures. An experimental study results in the attainment of complete wave fields that illustrate 2D topological waveguides and multi-polarized wave control in a physical testbed. The outcomes from this work provide insight that will aid future research on 3D topological mechanical metamaterials and reveal the applicability of the proposed metamaterial for wave control applications.

[A single-center retrospective analysis of 77 traumatic arterial injuries of lower extremities].

Objective: To analyze the treatment and clinical prognosis of lower extremity arterial injury caused by trauma. Methods: The clinical data of 77 patients with traumatic lower extremity arterial injury admitted to Department of Vascular Surgery,Yichang Central People's Hospital from January 2013 to June 2021 were collected retrospectively. There were 65 males and 12 females, with an average age of 47.4 years (range: 7 to 75 years). Among the 77 patients, 56 cases (72.7%) had open injury and 21 cases (27.3%) had closed injury. Iliac artery was injured in 9 cases (11.7%), common femoral artery in 7 cases (9.1%), superficial femoral artery in 1 case (1.3%), popliteal artery in 11 cases (14.3%) and inferior knee artery in 49 cases (63.6%). The treatment methods and clinical effects were analyzed. Results: One case with pelvic fracture combined the internal iliac artery injury and 1 case with multiple injuries involving the common femoral artery died of circulatory failure before surgery. Seventy-five cases received vascular-related operations, including arterial ligation in 24 cases, arterial reconstruction in 40 cases, stent graft implantation in 1 case, primary amputation in 2 cases, and arterial embolization in 8 cases. The overall mortality rate was 6.5% (5/77), all of which were closed injuries. Except for 2 cases who died before surgery, 3 cases with pelvic fracture combined the internal iliac artery injury died of multiple organ failure after internal iliac artery embolization. There were 8 cases received amputation (10.4%, 8/77), 5 cases with closed injury and 3 cases with open injury. In addition to 2 cases with primary amputation, 6 cases underwent secondary amputation due to ischemia-reperfusion injury after revascularization (4 cases with popliteal artery injury and 2 cases with subpatellar artery injury). The average followed-up time was 17 months (range: 2 months to 8 years). One patient with femoral artery injury underwent autologous great saphenous vein bypass, and lower limb artery CT angiography was re-examined 6 months after the operation, and 30% distal anastomotic stenosis was found. Ankle brachial index<0.8 was found in two patients 1 year after popliteal artery repair, but none of the patients had intermittent claudication symptoms, and no further intervention was performed. Five patients suffered delayed healing due to severe lower limb injury, fracture and skin injury. Among them, 2 cases had poor wound healing at the stump of amputation, which gradually healed 3 to 5 months after several debridements. The other 3 vascular injury combined with tibial fracture patients had delayed tibial healing after surgery, but no symptoms of vascular ischemia occurred. All the other patients recovered well and no other serious complications occurred. Conclusions: The proportion of death and disability in patients with lower limb artery injury caused by trauma is high. Active and orderly surgical repair according to the site and type of injury can reduce the mortality, save the function of the affected limb, and promote the healing of injury.

[Epidemiological characteristics and the establishment and evaluation of a risk prediction model for nosocomial infection in burn patients].

Objective: To find the epidemiological characteristics of nosocomial infection in burn patients, to establish a risk prediction model for nosocomial infection in burn patients based on the screened independent risk factors of the infection, and to analyze its predictive value. Methods: A retrospective case series study was conducted. From May 2016 to December 2019, 3 475 burn patients who were admitted to the Department of Burns of Affiliated Hospital of Jiangnan University met the inclusion criteria, including 2 290 males and 1 185 females, aged from 1 to 94 years. The incidence of nosocomial infection, the detection site and specific composition of pathogenic bacteria were counted. The patients were randomly divided into training group (2 434 cases) and verification group (1 041 cases) in R 4.1.3 statistic software with a ratio of about 7∶3. Factors including gender, age, total burn area, combination of full-thickness burn/inhalation injury/shock/diabetes on admission, admission to intensive care unit (ICU), status of central venous catheterization/endotracheal intubation/urethral catheter indwelling/surgery, nosocomial infection status, days of antibiotic use, and days of hospital stay of patients were compared between the two groups. According to the occurrence of nosocomial infection, the patients were divided into nosocomial infection group (102 cases) and non-nosocomial infection group (3 373 cases), and in addition to the aforementioned data, non-nosocomial infection related data, the season of admission and types of antibiotics used were compared between the two groups. The above-mentioned data were statistically analyzed with one-way analysis of independent sample t test, chi-square test, and Mann-Whitney U test, and the indicators with statistically significant differences between nosocomial infection group and non-nosocomial infection group were included as variables in multivariate logistic regression analysis to screen independent risk factors for the development of nosocomial infection in 3 475 burn patients. On the basis of independent risk factors and important clinical characteristics, a nomogram prediction model was constructed for the risk of developing nosocomial infection of burn patients in training group. In both training group and verification group, receiver operating characteristic (ROC) curves for prediction of nosocomial infection by the prediction model were plotted, and the area under the ROC curve was calculated; calibration curves were plotted to evaluate the conformity between the predicted results of the prediction model and the actual situation; clinical decision curves were plotted to evaluate the clinical utility of the prediction model. Results: The incidence of nosocomial infection of patients included in this study was 2.94% (102/3 475); pathogens were detected from 212 specimens, mainly wound (78 cases, accounting for 36.79%) and blood (64 cases, accounting for 30.19%) specimens; 250 strains of pathogenic bacteria were detected, mainly gram-negative bacteria (153 strains, accounting for 61.20%). All clinical characteristics of patients between training group and verification group were similar (P>0.05). There were statistically significant differences between patients in nosocomial infection group and non-nosocomial infection group in the aspects of age, total burn area, days of antibiotic use, antibiotic use type, days of hospital stay, combination of full-thickness burn, combination of inhalation injury, combination of shock, ICU admission status, central venous catheterization status, endotracheal intubation status, urethral catheter indwelling status, surgery status (with Z values of 4.41, 14.95, 15.70, 650.32, and 13.73, χ2 values of 151.09, 508.30, 771.20, 955.79, 522.67, 967.40, 732.11, and 225.35, respectively, P<0.01). ICU admission, endotracheal intubation, urethral catheter indwelling, and days of hospital stay were independent risk factors for developing nosocomial infection by 3 475 burn patients (with odds ratios of 5.99, 3.39, 9.32, and 6.21, 95% confidence intervals of 2.25-15.99, 1.56-7.39, 2.77-31.31, and 2.48-15.92, respectively, P<0.01). In training group and verification group, the area under ROC curves of the nosocomial infection prediction model based on independent risk factors, total burn area, and central vein catheterization were both 0.97 (with both 95% confidence intervals being 0.95-0.99); the calibration curve analysis showed that the prediction results of the prediction model were in good agreement with the actual situation; the clinical decision curve analysis showed that the prediction model had good clinical utility. Conclusions: The nosocomial infection in burn patients is mainly caused by gram-negative bacteria, with wound as the main infection site, and the independent risk factors including ICU admission, endotracheal intubation, urethral catheter indwelling, and days of hospital stay. Based on independent risk factors and important clinical features, the risk prediction model for nosocomial infection has a good ability to predict nosocomial infection in burn patients.

[Evidence-based progress for the risk events of paclitaxel devices in treatment of peripheral artery disease].

With the development of endovascular technology for peripheral arterial diseases, paclitaxel drug-eluting stents and drug-coated balloons have been widely used in recent years. It has been proved that paclitaxel-coated devices have good clinical effects in reducing vascular restenosis. However, the clinical safety of paclitaxel devices has encountered challenges, some of the studies have shown that paclitaxel-coated devices may increase long-term mortality. In addition, some studies have confirmed the effectiveness and safety of paclitaxel devices, leading to this topic becoming the focus and hot spot of global attention. Whether paclitaxel-coated devices increase the risk of long-term death, whether paclitaxel doses are related to mortality, and the pharmacokinetics of paclitaxel devices should be examined.

Dynamics of Kresling origami deployment.

Origami-inspired structures have a rich design space, offering new opportunities for the development of deployable systems that undergo large and complex yet predictable shape transformations. There has been growing interest in such structural systems that can extend uniaxially into tubes and booms. The Kresling origami pattern, which arises from the twist buckling of a thin cylinder and can exhibit multistability, offers great potential for this purpose. However, much remains to be understood regarding the characteristics of Kresling origami deployment. Prior studies have been limited to Kresling structures' kinematics, quasistatic mechanics, or low-amplitude wave responses, while their dynamic behaviors with large shape change during deployment remain unexplored. These dynamics are critical to the system design and control processes, but are complex due to the strong nonlinearity, bistability, and potential for off-axis motions. To advance the state of the art, this research seeks to uncover the deployment dynamics of Kresling structures with various system geometries and operating strategies. A full, six-degrees-of-freedom model is developed and employed to provide insight into the axial and off-axis dynamic responses, revealing that the variation of key geometric parameters may lead to regions with qualitatively distinct mechanical responses. Results illustrate the sensitivity of dynamic deployment to changes in initial condition and small variations in geometric design. Further, analyses show how certain geometries and configurations affect the stiffness of various axial and off-axis deformation modes, offering guidance on the design of systems that deploy effectively while mitigating the effects of off-axis disturbances. Overall, the research outcomes suggest the strong potential of Kresling-based designs for deployable systems with robust and tunable performance.

Three phytotoxins produced by Neopestalotiopsis clavispora, the causal agent of ring spot on Kadsura coccinea.

Phytotoxins are widely found in plant pathogens. In recent years, many diseases caused by Neopestalotiopsis clavispora have been reported. To better understand the pathogenicity of N. clavispora, a solid fermentation strategy was employed to isolate and identify virulence factors afritoxinone B, afritoxinone A and oxysporone. The phytotoxic activities of these toxins were evaluated. Oxysporone exhibited high levels of phytotoxic activity after 72 h and the lesion area ranged from 21.5-84.3 mm2 after 9 days of treatment. The phytotoxic activities of the other two compounds were lower than that for oxysporone. The phytotoxic activity towards non-host organisms was also assessed for the three analyzed compounds; phytotoxic activity was observed in each case. Based on these results, we conclude that oxysporone is the main virulence factor in N. clavispora. We also suggest that each of the three compounds were non-host-specific toxins (NHST). To our knowledge, this is the first study to analyze phytotoxins produced by N. clavispora.

Cisplatin induces apoptosis of A549 cells by downregulating peroxidase V.

The article "Cisplatin induces apoptosis of A549 cells by downregulating peroxidase V" by X. Chen, K.-W. Wang, Y.-Q. Chen, published in Eur Rev Med Pharmacol Sci 2018; 22(21): 7289-7295 has been withdrawn.

Cisplatin induces apoptosis of A549 cells by downregulating peroxidase V.

OBJECTIVE: The purpose of the study was to investigate the role of peroxidase V (Prx V) in Cisplatin-induced apoptosis of A549 cells and its underlying mechanism. MATERIALS AND METHODS: MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay was conducted to evaluate the regulatory effect of Cisplatin on the survival of A549 cells. ROS (Reactive Oxygen Species) level in A549 cells induced with 0, 2, 4, and 6 mol/L Cisplatin for 24 h was determined using immunofluorescence. Apoptosis of Cisplatin-induced A549 cells was determined by immunofluorescence and flow cytometry, respectively. Western blot was performed to detect protein levels of Prx V, Bcl-2 (B-cell lymphoma 2), BAD ,and caspase-3 in Cisplatin-induced A549 cells. RESULTS: Survival rate of A549 cells gradually decreased with the increased dose of Cisplatin. Immunofluorescence results elucidated that cellular ROS level in Cisplatin-induced A549 cells increases in a dose-dependent manner. Both immunofluorescence and flow cytometry results revealed that the apoptotic rate of A549 cells increases with the elevation of Cisplatin dose. Besides, the apoptotic rate and ROS level of A549 cells were reduced by NAC pretreatment. Western blot results showed that the protein level of Prx V remarkably decreased in a dose-dependent manner, whereas Prx II expression did not change. With the treatment prolongation of 4 µmol/L Cisplatin in A549 cells, Bcl-2 and caspase-3 were downregulated, while BAD upregulated. CONCLUSIONS: Cisplatin treatment induces the ROS production, increases the apoptotic rate and downregulates the Prx expression in A549 cells.

Metastable modular metastructures for on-demand reconfiguration of band structures and nonreciprocal wave propagation.

We present an approach to achieve adaptable band structures and nonreciprocal wave propagation by exploring and exploiting the concept of metastable modular metastructures. Through studying the dynamics of wave propagation in a chain composed of finite metastable modules, we provide experimental and analytical results on nonreciprocal wave propagation and unveil the underlying mechanisms that facilitate such unidirectional energy transmission. In addition, we demonstrate that via transitioning among the numerous metastable states, the proposed metastructure is endowed with a large number of bandgap reconfiguration possibilities. As a result, we illustrate that unprecedented adaptable nonreciprocal wave propagation can be realized using the metastable modular metastructure. Overall, this research elucidates the rich dynamics attainable through the combinations of periodicity, nonlinearity, spatial asymmetry, and metastability and creates a class of adaptive structural and material systems capable of realizing tunable bandgaps and nonreciprocal wave transmissions.

Overweight, obesity and adiposity in survivors of childhood brain tumours: a systematic review and meta-analysis.

Survivors of childhood brain tumours (SCBT) have increased cardiometabolic risks, but the determinants of these risks are unclear. This systematic review aims to compare the prevalence of overweight and obesity as well as adiposity measures between SCBT and non-cancer controls. The PubMed, EMBASE, MEDLINE, CINAHL and the Cochrane Library databases were searched. The primary outcomes were the prevalence of overweight and obesity based on body mass index. The secondary outcomes were adiposity measures including percent fat mass, waist-to-hip and waist-to-height ratios. Forty-one studies were included in the meta-analysis. The prevalence of overweight and obesity combined was similar between overall SCBT, SCBT excluding craniopharyngioma and non-cancer controls (42.6%, 95% CI 30.1-55.1 vs. 31.7%, 95% CI 20.4-43.0 vs. 40.4%, 95% CI 34.0-46.8). We also found that SCBT have higher percent fat mass (mean difference 4.1%, 95% CI 2.0-6.1), waist-to-hip ratio (mean difference 0.07, 95% CI 0.02-0.13) and waist-to-height ratio (mean difference 0.06, 95% CI 0.01-0.10) than non-cancer controls. We conclude that SCBT have similar overweight and obesity distribution but higher adiposity than non-cancer controls. More studies were needed to explore the determinants of adiposity and its contribution to cardiometabolic outcomes in SCBT.

Origami-based earthworm-like locomotion robots.

Inspired by the morphology characteristics of the earthworms and the excellent deformability of origami structures, this research creates a novel earthworm-like locomotion robot through exploiting the origami techniques. In this innovation, appropriate actuation mechanisms are incorporated with origami ball structures into the earthworm-like robot 'body', and the earthworm's locomotion mechanism is mimicked to develop a gait generator as the robot 'centralized controller'. The origami ball, which is a periodic repetition of waterbomb units, could output significant bidirectional (axial and radial) deformations in an antagonistic way similar to the earthworm's body segment. Such bidirectional deformability can be strategically programmed by designing the number of constituent units. Experiments also indicate that the origami ball possesses two outstanding mechanical properties that are beneficial to robot development: one is the structural multistability in the axil direction that could contribute to the robot control implementation; and the other is the structural compliance in the radial direction that would increase the robot robustness and applicability. To validate the origami-based innovation, this research designs and constructs three robot segments based on different axial actuators: DC-motor, shape-memory-alloy springs, and pneumatic balloon. Performance evaluations reveal their merits and limitations, and to prove the concept, the DC-motor actuation is selected for building a six-segment robot prototype. Learning from earthworms' fundamental locomotion mechanism-retrograde peristalsis wave, seven gaits are automatically generated; controlled by which, the robot could achieve effective locomotion with qualitatively different modes and a wide range of average speeds. The outcomes of this research could lead to the development of origami locomotion robots with low fabrication costs, high customizability, light weight, good scalability, and excellent re-configurability.

Dynamics of a bistable Miura-origami structure.

Origami-inspired structures and materials have shown extraordinary properties and performances originating from the intricate geometries of folding. However, current state of the art studies have mostly focused on static and quasistatic characteristics. This research performs a comprehensive experimental and analytical study on the dynamics of origami folding through investigating a stacked Miura-Ori (SMO) structure with intrinsic bistability. We fabricate and experimentally investigated a bistable SMO prototype with rigid facets and flexible crease lines. Under harmonic base excitation, the SMO exhibits both intrawell and interwell oscillations. Spectrum analyses reveal that the dominant nonlinearities of SMO are quadratic and cubic, which generate rich dynamics including subharmonic and chaotic oscillations. The identified nonlinearities indicate that a third-order polynomial can be employed to approximate the measured force-displacement relationship. Such an approximation is validated via numerical study by qualitatively reproducing the phenomena observed in the experiments. The dynamic characteristics of the bistable SMO resemble those of a Helmholtz-Duffing oscillator (HDO); this suggests the possibility of applying the established tools and insights of HDO to predict origami dynamics. We also show that the bistability of SMO can be programmed within a large design space via tailoring the crease stiffness and initial stress-free configurations. The results of this research offer a wealth of fundamental insights into the dynamics of origami folding, and provide a solid foundation for developing foldable and deployable structures and materials with embedded dynamic functionalities.

The effectiveness of interventions to treat hypothalamic obesity in survivors of childhood brain tumours: a systematic review.

BACKGROUND: Survivors of childhood brain tumours (SCBT) are at risk of type 2 diabetes and cardiovascular diseases. Obesity is a major driver of cardiometabolic diseases in the general population, and interventions that tackle obesity may lower the risk of these chronic diseases. The goal of this systematic review was to summarize current evidence for the presence of interventions to manage obesity, including hypothalamic obesity, in SCBT. METHODS: The primary outcome of this review was the body mass index z-score change from baseline to the end of the intervention and/or follow-up. Literature searches were conducted in PsycINFO, CINAHL, the Cochrane Library, Medline, SPORTDiscus, EMBASE and PubMed. Two reviewers completed study evaluations independently. RESULTS: Eleven publications were included in this systematic review (lifestyle intervention n = 2, pharmacotherapy n = 6 and bariatric surgery n = 3). While some studies demonstrated effectiveness of interventions to manage obesity in SCBT and alter markers of obesity and cardiometabolic risk, the evidence base was limited and of low quality, and studies focused on hypothalamic obesity. We conclude that there is urgent need to conduct adequately powered trials of sufficient duration, using existing and novel therapies to manage obesity, reduce the burden of cardiometabolic disorders and improve outcomes in SCBT.

Hybrid methodology for tuberculosis incidence time-series forecasting based on ARIMA and a NAR neural network.

Tuberculosis (TB) affects people globally and is being reconsidered as a serious public health problem in China. Reliable forecasting is useful for the prevention and control of TB. This study proposes a hybrid model combining autoregressive integrated moving average (ARIMA) with a nonlinear autoregressive (NAR) neural network for forecasting the incidence of TB from January 2007 to March 2016. Prediction performance was compared between the hybrid model and the ARIMA model. The best-fit hybrid model was combined with an ARIMA (3,1,0) × (0,1,1)12 and NAR neural network with four delays and 12 neurons in the hidden layer. The ARIMA-NAR hybrid model, which exhibited lower mean square error, mean absolute error, and mean absolute percentage error of 0·2209, 0·1373, and 0·0406, respectively, in the modelling performance, could produce more accurate forecasting of TB incidence compared to the ARIMA model. This study shows that developing and applying the ARIMA-NAR hybrid model is an effective method to fit the linear and nonlinear patterns of time-series data, and this model could be helpful in the prevention and control of TB.

Self-locking degree-4 vertex origami structures.

A generic degree-4 vertex (4-vertex) origami possesses one continuous degree-of-freedom for rigid folding, and this folding process can be stopped when two of its facets bind together. Such facet-binding will induce self-locking so that the overall structure stays at a pre-specified configuration without additional locking elements or actuators. Self-locking offers many promising properties, such as programmable deformation ranges and piecewise stiffness jumps, that could significantly advance many adaptive structural systems. However, despite its excellent potential, the origami self-locking features have not been well studied, understood, and used. To advance the state of the art, this research conducts a comprehensive investigation on the principles of achieving and harnessing self-locking in 4-vertex origami structures. Especially, for the first time, this study expands the 4-vertex structure construction from single-component to dual-component designs and investigates their self-locking behaviours. By exploiting various tessellation designs, this research discovers that the dual-component designs offer the origami structures with extraordinary attributes that the single-component structures do not have, which include the existence of flat-folded locking planes, programmable locking points and deformability. Finally, proof-of-concept experiments investigate how self-locking can effectively induce piecewise stiffness jumps. The results of this research provide new scientific knowledge and a systematic framework for the design, analysis and utilization of self-locking origami structures for many potential engineering applications.

Plant-inspired adaptive structures and materials for morphing and actuation: a review.

Plants exhibit a variety of reversible motions, from the slow opening of pine cones to the impulsive closing of Venus flytrap leaves. These motions are achieved without muscles and they have inspired a wide spectrum of engineered materials and structures. This review summarizes the recent developments of plant-inspired adaptive structures and materials for morphing and actuation. We begin with a brief overview of the actuation strategies and physiological features associated to these plant movements, showing that different combinations of these strategies and features can lead to motions with different deformation characteristics and response speeds. Then we offer a comprehensive survey of the plant-inspired morphing and actuation systems, including pressurized cellular structures, osmotic actuation, anisotropic hygroscopic materials, and bistable systems for rapid movements. Although these engineered systems are vastly different in terms of their size scales and intended applications, their working principles are all related to the actuation strategies and physiological features in plants. This review is to promote future cross-disciplinary studies between plant biology and engineering, which can foster new solutions for many applications such as morphing airframes, soft robotics and kinetic architectures.

Uncovering the deformation mechanisms of origami metamaterials by introducing generic degree-four vertices.

Origami-based design holds promise for developing new mechanical metamaterials whose overall kinematic and mechanical properties can be programmed using purely geometric criteria. In this article, we demonstrate that the deformation of a generic degree-four vertex (4-vertex) origami cell is a combination of contracting, shearing, bending, and facet-binding. The last three deformation mechanisms are missing in the current rigid-origami metamaterial investigations, which focus mainly on conventional Miura-ori patterns. We show that these mechanisms provide the 4-vertex origami sheets and blocks with new deformation patterns as well as extraordinary kinematical and mechanical properties, including self-locking, tridirectional negative Poisson's ratios, flipping of stiffness profiles, and emerging shearing stiffness. This study reveals that the 4-vertex cells offer a better platform and greater design space for developing origami-based mechanical metamaterials than the conventional Miura-ori cell.

Role of IL-8 gene polymorphisms in glioma development in a Chinese population.

This case-control study aimed to investigate the role of -251 T>A (rs4073) and -781 C>T (rs2227306) polymorphisms in the interleukin-8 (IL-8) gene in the development of glioma in a Chinese population. One hundred and twenty-seven glioma patients and 284 healthy control subjects were recruited to this study between February 2013 and December 2014. The IL-8 -251 T>A (rs4073) and -781 C>T (rs2227306) polymorphisms were genotyped by polymerase chain reaction coupled with restriction fragment length polymorphism. The patients and control subjects were comparable by gender (X2 = 1.24, P = 0.27), tobacco smoking status (X2 = 0.80, P = 0.37), alcohol consumption status (X2 = 0.97, P = 0.32), and family history of cancer (X2 = 1.54, P = 0.22). The age of glioma patients was statistically lower than that of control subjects (t = 2.87, P = 0.002). The chi-square test revealed the lack of any statistically significant differences in the genotype distributions of IL-8 rs4073 (X2 = 0.89, P = 0.64) and rs2227306 (X2 = 2.58, P = 0.28) between the glioma patients and control subjects. Unconditional logistic regression analysis revealed that the IL-8 rs4073 and rs2227306 gene polymorphisms did not contribute to the development of glioma. In conclusion, we determined that there is a lack of evidence suggesting a significant association between the IL-8 rs4073 and rs2227306 gene polymorphisms and the development of glioma in a Chinese population.

Recoverable and Programmable Collapse from Folding Pressurized Origami Cellular Solids.

We report a unique collapse mechanism by exploiting the negative stiffness observed in the folding of an origami solid, which consists of pressurized cells made by stacking origami sheets. Such a collapse mechanism is recoverable, since it only involves rigid folding of the origami sheets and it is programmable by pressure control and the custom design of the crease pattern. The collapse mechanism features many attractive characteristics for applications such as energy absorption. The reported results also suggest a new branch of origami study focused on its nonlinear mechanics associated with folding.