Publications by authors named "Chang-Qing Chen"

The confinement of waves within a waveguide can enable directional transmission of signals, which has found wide applications in communication, imaging, and signal isolation. Extending this concept to static systems, where material deformation is piled up along a spatial trajectory, remains elusive due to the sensitivity of localized deformation to structural defects and impurities. Here, we propose a general framework to characterize localized static deformation responses in two-dimensional generic static mechanical metamaterials, by exploiting the duality between space in static systems and time in one-dimensional non-reciprocal wave systems.

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Mechanical computing provides an information processing method to realize sensing-analyzing-actuation integrated mechanical intelligence and, when combined with neural networks, can be more efficient for data-rich cognitive tasks. The requirement of solving implicit and usually nonlinear equilibrium equations of motion in training mechanical neural networks makes computation challenging and costly. Here, an explicit mechanical neuron is developed of which the response can be directly determined without the need of solving equilibrium equations.

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Mechanical computing requires matter to adapt behavior according to retained knowledge, often through integrated sensing, actuation, and control of deformation. However, inefficient access to mechanical memory and signal propagation limit mechanical computing modules. To overcome this, we developed an in-memory mechanical computing architecture where computing occurs within the interaction network of mechanical memory units.

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The combination of broken Hermiticity and band topology in physical systems unveils a novel bound state dubbed as the non-Hermitian skin effect (NHSE). Active control that breaks reciprocity is usually used to achieve NHSE, and gain and loss in energy are inevitably involved. Here, we demonstrate non-Hermitian topology in a mechanical metamaterial system by exploring its static deformation.

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Information processing using material's own properties has gained increasing interest. Mechanical metamaterials, due to their diversity of deformation modes and wide design space, can be used to realize information processing, such as computing and storage. Here a mechanical metamaterial system is demonstrated for material-based encoding and storage of data through programmed reconfigurations of the metamaterial's structured building blocks.

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Robotic materials, with coupled sensing, actuation, computation, and communication, have attracted increasing attention because they are able to not only tune their conventional passive mechanical property via geometrical transformation or material phase change but also become adaptive and even intelligent to suit varying environments. However, the mechanical behavior of most robotic materials is either reversible (elastic) or irreversible (plastic), but not transformable between them. Here, a robotic material whose behavior is transformable between elastic and plastic is developed, based upon an extended neutrally stable tensegrity structure.

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Transformations in shape are critical to actuation in engineered metamaterials. Existing engineering metamaterials are typically limited to a small number of shape transformations that must be built-in during material synthesis. Here, inspired by the multistability and programmability of kirigami-based self-folding elements, a robust framework is introduced for the construction of sequentially programmable and reprogrammable mechanical metamaterials.

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Embedding mechanical logic into soft robotics, microelectromechanical systems (MEMS), and robotic materials can greatly improve their functional capacity. However, such logical functions are usually pre-programmed and can hardly be altered during in-life service, limiting their applications under varying working conditions. Here, we propose a reprogrammable mechanological metamaterial (ReMM).

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This study was aimed to clarify the toxicity indoor and inhibition effect of biocontrol strain NJ13 and its mixture with chemical fungicides against Fusarium solani causing ginseng root rot. The method of mycelial growth rate and Sun Yunpei method were used to determine the indoor toxicity and co-toxicity coefficient of strain NJ13 and their mixture with chemical pesticides against F. solani.

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This study was aimed to isolate the strains with both disease resistance and growth-promoting, and clarify the field application effects of the strain for laying the further application foundation. The strains with good antagonistic effect were isolated from the 298 strains in Panax ginseng and the soil by plate confrontation method. The nitrogen fixation potential was verified by Ashby medium.

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Northeast China is one of the most important farming regions in China, due to its great contribution to national food security. Crop production is a main source of carbon emission. To assess the differences in carbon footprints of major grain crop production will benefit the achievement of low carbon agriculture.

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Objective To evaluate the effect of interventions for premature ejaculation (PE) in the management of patients with chronic prostatitis and secondary premature ejaculation. Methods Totally 90 patients diagnosed as chronic prostatitis with PE were randomly divided into control group (n=45) and interventional group (n=45). Control group received a conventional therapy consisted of oral administration of antibiotics,α-receptor blocker,and proprietary Chinese medicine for clearing away heat and promoting diuresis.

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Endophytic bacteria which was producing indoleacetic acid was screened from Panax ginseng by using the Salkowski method. The active strain was also tested for its ability of nitrogen fixation by using the Ashby agar plates, the PKV plates and quantitative analysis of Mo-Sb-Ascrobiology acid colorimetry was used to measure its ability of phosphate solubilization, for its ability of potassium solubilization the silicate medium and flame spectrophotometry was used, for its ability of producing siderophores the method detecting CAS was used, for its ability of producing ACC deaminase the Alpha ketone butyric acid method was applied. And the effect on promoting growth of seed by active strain was tested.

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The stability, elastic properties, and electronic structure of germanane nanoribbons (GeNRs) are studied from first-principles calculations. When using atomic H as the hydrogen source, a germanane monolayer spontaneously breaks into ribbons. GeNRs can be easily stretched due to their small in-plane stiffness, suggesting that it is feasible to modulate their properties by strain.

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By using rice growth period, yield and climate observation data during the recent two decades, the impact of climate warming on rice in Northeast China was investigated by mathematical statistics methods. The results indicated that in the three provinces of Northeast China, the average, maximum and minimum temperatures in rice growing season were on the. rise, and the rainfall presented a downward trend during 1989-2009.

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Objective: To investigate the clinical effects of plate and xenogenic bony plate for the treatment of nonunion of femoral shaft fracture after initial fixation with locked intramedullary nailing.

Methods: From February 2006 to June 2013, 21 cases with nonunion of femoral shaft fracture after initial fixation with locked intramedullary nailing were treated with femoral plate and contralateral xenogenic bony plate. There were 12 males and 9 females with an average age of 34.

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Purpose: To establish a classification system for the different types of posterior tibial plateau fractures (PTPF), and to explore the fracture patterns and early results of treatment.

Methods: 39 PTPFs patients who received surgeries through posteromedial or (and) posterolateral knee approaches were analyzed retrospectively.

Results: There were 5 types of PTPFs identified in the new classification system: posteromedial split fracture (type I, 7 patients), posterolateral split fracture (type II, 5 patients), posterolateral depression fracture (type III, 11 patients), posterolateral split and depression fracture (type IV, 2 patients), and posteromedial split combined with posterolateral depression fracture (type V, 14 patients).

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To reveal the colonization characteristics in host of endophytic biocontrol bacteria NJ13 isolated from Panax ginseng, this study obtained the marked strain NJ13-R which was double antibiotic resistant to rifampicin and streptomycin through enhancing the method of inducing antibiotic. The colonization characteristics in ginseng and its biocontrol efficiency against Alternaria spot of ginseng in the field were studied. The results showed that the strain could colonize in root, stem and leaf of ginseng and the colonization amount was positive correlated with inoculation concentration.

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A field experiment was conducted to study the effects of all-day warming on the growth, development and yield of winter wheat cultivars bred in different periods under free air temperature increase (FATI) in Xuzhou and Danyang, Jiangsu Province. Warming decreased the effective tillers by 5.2% and 9.

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Ethnopharmacological Relevance: Leaves of Lithocarpus polystachyus Rehd. are used for the treatment of disorders such as diabetes, hypertension, and epilepsy in folk medicine of South China. The possible antidiabetic effects of the leaves were investigated in experimental type 2 and type 1 diabetic rats.

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Objective: To investigate the feasibility and safety of the treatment for thoracolumbar fractures with transpedicular intracorporeal hydroxyapatite grafting and pedicle screw fixation via paraspinal approach.

Methods: From June 2007 to December 2008, 19 cases of thoracolumbar fractures were treated with transpedicular intracorporeal hydroxyapatite grafting and pedicle screw fixation via paraspinal approach. There were 7 female and 12 male, ranging from 21 to 57 years of age (mean 40.

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The active estrogen estradiol (E2) stimulates breast cancer cell (BCC) growth, whereas the androgen dihydrotestosterone (DHT) has shown an antiproliferative effect. The principal product synthesized by the 17beta-hydroxysteroid dehydrogenase type 1 (17beta-HSD1) is E2, although we have demonstrated that the purified enzyme also inactivates DHT. However, the direct roles of 17beta-HSD1 in sex-hormone regulation and BCC proliferation have not been completely established.

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Hydrogen sulfide (H(2)S), as an endogenous gas signaling molecule with important biological function that has been found recently, may play a protection in ischemic reperfusion (I/R) myocardium. We investigated the cardioprotective effect of H(2)S in rats model of ischemic reperfusion in vivo and a probably influence on the expression of survivin, an anti-apoptosis gene. Animals were randomly divided into 3 groups and received either vehicle, sodium hydrosulfide (NaHS) or DL-propargylglycine (PAG) respectively everyday for 1 week before surgery and the treatment continued for a further 2 d after I/R till the animals were sacrificed.

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Objective: To evaluate curative effect of plate and xenogenic bony plate were applied in refracture in plate-screw fixation of femoral shaft.

Methods: Thirteen cases of refracture in plate-screw fixation of femoral shaft included 8 males and 5 females, average age was 31.2 years ranging from 14 to 57.

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