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Flexible polymer dielectrics for capacitive energy storage that can function well at elevated temperatures are increasingly in demand for continuously advancing and miniaturizing electrical devices. However, traditional high-resistance polymer dielectrics composed of aromatic backbones have a compromised band gap ( E g ) and hence suffer from low breakdown strength and a huge loss at high temperatures. Here, based on the density functional theory (DFT) calculations, rigid and non-coplanar alicyclic segments are introduced into the polyimide backbone to overcome the incompatibility of a high glass transition temperature ( T g ) and large E g . Thanks to the large optical E g (∼4.6 eV) and high T g (∼277 °C), the all-alicyclic polyimide at 200 °C delivers a maximum discharge energy density ( U e ) of 5.01 J cm -3 with a charge-discharge efficiency ( η ) of 78.1% at 600 MV m -1 , and a record U e of 2.55 J cm -3 at η = 90%, which is 10-fold larger than that of the state-of-art commercial polyetherimides (PEIs). In addition, compared with aromatic polyimides, the all-alicyclic polyimide possesses a better self-clearing characteristic due to a smaller ratio of carbon to hydrogen and oxygen, which facilitates its long-term reliability in practical applications.

The shale of the Upper Ordovician Wufeng Formation and the Lower Silurian Longmaxi Formation in the Xichang Basin is the main replacement horizon for the shale gas exploration being conducted in the Sichuan Province, except for the Sichuan Basin. The fine identification and classification of the types of shale facies are important for shale gas exploration and development evaluation. However, the lack of systematic experimental studies on rock physical characteristics and micro-pore structures leads to a lack of physical evidence for the comprehensive prediction of shale sweet spots. Therefore, the present study used different means, such as core observation, total organic carbon content (TOC), helium porosity measurement, X-ray diffraction analysis, and mechanical properties analysis, in combination with the analysis of the whole rock mineral composition and characteristics of shale, for the identification and classification of the lithofacies of the shale layer, the systematic petrology and hardness measurement of the shale samples with different lithofacies, and discussion of the dynamic and static elastic properties of the shale samples and the control factors. It was revealed that nine types of lithofacies existed in the Wufeng Formation- the Long1 1 sub-member in the Xichang Basin, among which moderate organic carbon content-siliceous shale facies, moderate organic carbon content-mixed shale facies, and high-organic carbon content-siliceous shale facies were the best lithofacies with the optimum reservoir conditions, providing sufficient space for shale gas accumulation. The siliceous shale facies mainly developed organic pores and fractures, and the pore texture was excellent overall. The mixed shale facies mainly developed intergranular pores and mold pores, with a preference toward pore texture. The argillaceous shale facies mainly developed dissolution pores and interlayer fractures, and the pore texture was relatively poor. The geochemical characteristics of the organic-rich shale samples with TOC > 3.5% revealed that the sample was composed of microcrystalline quartz grains as the rock support framework, while the intergranular pores were located between the rigid quartz grains, which exhibited hard pores in the analysis of their mechanical properties. In the relatively organic-poor shale samples with TOC < 3.5%, the quartz source was mainly terrigenous clastic quartz, and the sample was composed of plastic clay minerals as the rock support skeleton, while the intergranular pores were located between argillaceous particles, which exhibited soft pores in the analysis of their mechanical properties. The difference in the rock fabric of the shale samples resulted in an ″initial increase followed by a decrease″ trend of velocity with quartz content, with the organic-rich shale samples exhibiting low velocity-porosity and velocity-organic matter content change rate, and the two kinds of rocks were easier to distinguish in the correlation diagram of the combined elastic parameters such as the P-wave impedance-Poisson ratio and the elastic modulus-Poisson ratio. The samples dominated by biogenic quartz exhibited greater hardness and brittleness, while the samples dominated by terrigenous clastic quartz exhibited lower hardness and brittleness. These results could serve as a basis for logging interpretation and seismic ″sweet spot″ prediction of high-quality shale gas reservoirs in Wufeng Formation-Member 1 of the Longmaxi Formation., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Developing novel lead-free perovskite materials with suitable bandgaps and superior thermal stability is crucial to boost their applications in next-generation photovoltaic technologies. High throughput screening combined with the first principles method can accurately and effectively screen out promising perovskites. Herein, we select two lead-free all-inorganic halide double perovskite materials Cs 2 KMI 6 (M = Ga, In) from 1026 compounds with the criteria including appropriate structure factors, positive decomposition energies, and suitable direct bandgaps. We investigated the thermal and mechanical stability, geometric and electronic structures, photoelectric properties, and defect formation energies for both perovskites Cs 2 KMI 6 (M = Ga, In). They can exhibit excellent structural formability and stability through the analysis of structure factors, elastic constants, and stable chemical potential regions. In addition, we investigate the defect effects of Cs 2 KMI 6 (M = Ga, In) on the photovoltaic performance by evaluating the defect formation energies and transition energy levels. Based on the HSE06 functional, we calculated the energy band structures of these two compounds and demonstrate the direct bandgaps of 1.69 eV (HSE06) and 2.16 eV (HSE06) for Cs 2 KGaI 6 and Cs 2 KInI 6 , respectively. Moreover, we predicted excellent spectroscopic limited maximum efficiencies (SLMEs) of these two perovskites with high light absorption coefficients (around 10 5 cm -1 ), for instance, the SLME of Cs 2 KGaI 6 can reach as high as 28.39%.

Objective: To investigate the effectiveness and safety of low molecular weight heparin combined with aspirin for perioperative prophylactic anticoagulation in patients with lower extremity fracture after splenectomy., Methods: The clinical data of 50 patients with splenic rupture combined with lower extremity fracture between January 2009 and June 2022 were retrospectively analyzed. All patients were given enoxaparin sodium at 48 hours after splenectomy, and stopped at 24 hours before fracture surgery. After fracture surgery, the patients were divided into aspirin group (group A, 15 cases), low molecular weight heparin group (group B, 16 cases), and low molecular weight heparin combined with aspirin group (group C, 19 cases) according to different anticoagulation regimens. The treatment course was 28 days. There was no significant difference in gender, age, body mass index, cause of injury, fracture site, time from injury to operation, complications, and other general data between groups ( P >0.05). The occurrence of venous thromboembolism (VTE) was observed; hemoglobin (Hb), platelet (PLT), D-D dimer, and fibrinogen degradation product (FDP) were recorded before operation and at 1, 3, and 7 days after operation, and the effect of anticoagulation regimen on coagulation function was observed. The incidences of wound complications and bleeding related complications were recorded, and the total perioperative blood loss, hidden blood loss, and overt blood loss were calculated., Results: The incidences of VTE in groups A, B, and C were 13.33% (2/15), 12.50% (2/16), and 5.26% (1/19), respectively, and there was no significant difference between groups ( χ 2 =0.770, P =0.680). There was no portal vein thrombosis and no VTE-related death in the 3 groups. There was no significant difference in the levels of Hb, PLT, D-D dimer, and FDP between groups before and after operation ( P >0.05); and there was no significant difference in total perioperative blood loss, hidden blood loss, and overt blood loss between groups ( P >0.05). No local skin necrosis was found in all patients. In group A, 1 case occurred redness and swelling of incision; in group B, 1 case had incision discharge, redness, and swelling, and 1 case had fat liquefaction; in group C, 1 case had repeated incision exudation accompanied by local tissue redness and swelling, and 1 case had local hematoma. The incidences of adverse incision in groups A, B, and C were 6.66% (1/15), 12.50% (2/16), and 11.76% (2/19), respectively, with no significant difference ( χ 2 =0.302, P =0.860). There were 4 cases of bleeding related complications, including 1 case of incision ecchymosis in groups A and B respectively, with the incidence of 6.66% and 6.25%, respectively; there was 1 case of incision hematoma and 1 case of bleeding in group C, with the incidence of 11.76%; showing no significant difference in the incidence of bleeding related complications between groups ( χ 2 =0.268, P =0.875)., Conclusion: Perioperative combined use of low molecular weight heparin and aspirin for prevention of anticoagulation in patients with splenic rupture and lower extremity fracture can effectively prevent the occurrence of VTE without increasing the incidence of complications, which is an effective and safe treatment method. However, whether the incidence of VTE can be reduced needs to be further studied by expanding the sample size.

Advanced polymer dielectrics with high energy density at elevated temperatures are highly desired to meet the requirements of modern electronic and electrical systems under harsh conditions. Herein, we report a novel polyimide/magnesium oxide (PI/MgO) nanodielectric that exhibits high energy storage density ( U e ) and charge-discharge efficiency ( η ) along with excellent cycling stability at elevated temperatures. Benefiting from the large bandgap of MgO and the extended interchain spacing of PI, the composite films can simultaneously achieve high dielectric constant and high breakdown strength, leading to enhanced energy storage density. The nanocomposite film doped with 0.1 vol% MgO can achieve a maximum U e of 2.6 J cm -3 and a η of 89% at 450 MV m -1 and 150 °C, which is three times that of the PI film under the same conditions. In addition, embedding ultralow content of inorganic fillers can avoid aggregation and facilitate its large-scale production. This work may provide a new paradigm for exploring polymer nanocomposites with excellent energy storage performance at high temperatures and under a high electric field.

Pomegranate ( Punica granatum L.) is a kind of fruit with significant economic, ecological and health values. AP2/ERF transcription factors belong to a large group of factors mainly found in plants and play key roles in plant growth and development. However, AP2/ERF genes in pomegranate and their implication in development and postharvest preservation have been little described. In this study, 116 PgAP2/ERF genes in pomegranate were identified and renamed based on their chromosomal distributions. Phylogenetic relationship with genes from other species, structures, duplications, annotations, cis -elements in promoter sequences, and protein-protein interaction networks among PgAP2/ERF proteins were comprehensively explored. Expression analysis revealed several PgAP2/ERFs associated with the phenotypes of pomegranate seed hardness, including PgAP2/ERF5 , PgAP2/ERF36 , PgAP2/ERF58 , and PgAP2/ERF86 . Subsequent analysis indicated that many differentially expressed PgAP2/ERF genes are potentially important regulators of pomegranate fruit development. Furthermore, expression of more than one-half of PgAP2/ERFs was repressed in 'Tunisian soft seed' pomegranate fruit under low-temperature cold storage. The results showed that 1-MCP implicated in promoting postharvest preservation of 'Tunisian soft seed' pomegranate upregulated the PgAP2/ERF4 , PgAP2/ERF15 , PgAP2/ERF26 , PgAP2/ERF30 , PgAP2/ERF35 and PgAP2/ERF45 genes compared to those under low-temperature cold storage. This indicates that these genes are important candidate genes involved in pomegranate postharvest preservation. In summary, the findings of the present study provide an important basis for characterizing the PgAP2/ERF family genes and provide information on the candidate genes involved in pomegranate fruit development and postharvest preservation.

Objective: To analyze the clinical characteristics, risk factors, and drug resistance of pathogenic bacteria in patients with blood stream infections (BSI) after orthopedic surgery, so as to provide reference and basis for clinical diagnosis and treatment., Methods: A retrospective analysis was made on the clinical data of 6 348 orthopedic patients admitted for surgery between January 2017 and December 2019. There were 3 598 males and 2 750 females. Their age ranged from 18 to 98 years, with an average of 66 years. The data of patients were collected, and the risk factors of BSI were analyzed by univariate analysis and logistic regression analysis. The distribution of BSI pathogenic bacteria, the results of drug sensitivity test, the incidence of BSI in patients after orthopedic surgery in different years, and the common sites of BSI secondary infection were summarized., Results: BSI occurred in 106 (1.67%) of 6 348 patients after orthopedic surgery. There were 71 cases (66.98%) of secondary infection. The mortality of postoperative BSI patients was 1.89%, and the difference was significant when compared with that of non-postoperative BSI patients (0.24%) ( χ 2 =5.313, P =0.021). The incidences of BSI in 2017, 2018, and 2019 were 1.18%, 1.53%, and 2.17%, respectively, showing an increasing trend year by year (trend χ 2 =6.610, P =0.037). Statistical analysis showed that the independent risk factors for BSI after orthopedic surgery ( P <0.05) included the trauma, length of hospital stay≥14 days, emergency surgery, postoperative leukocyte counting<4×10 9 /L, level of hemoglobin≤90 g/L, albumin≤30 g/L, the time of indwelling ureter>24 hours, use of deep vein catheter insertion, and merging other site infection. Blood culture showed 56 strains (52.83%) of Gram-positive bacteria, 47 strains (44.34%) of Gram-negative bacteria, and 3 strains (2.83%) of fungi. The top three pathogenic bacteria were coagulase negative Staphylococci (CNS; 36 strains, 33.96%), Escherichia coli (16 strains, 15.09%), and Staphylococcus aureus (15 strains, 14.15%). The detection rates of extended-spectum β-lactamases producing strains of Escherichia coli and Klebsiella pneumoniae were 56.25% (9/16) and 44.44% (4/9), respectively. The detection rates of methicillin-resistant strains in Staphylococcus aureus and CNS were 46.67% (7/15) and 72.22% (26/36), respectively., Conclusion: Postoperative BSI in orthopedic patients is caused by multiple factors. Preventive measures should be taken according to related risk factors and perioperative risk assessment should be strengthened. Staphylococcus and Escherichia coli are the most common pathogenic bacteria in BSI after orthopedic surgery. The infection rate and drug-resistant bacteria are increasing year by year. Therefore, drug resistance monitoring should be strengthened.

When elder arthritis patients suffered from complex supracondylar femoral fractures, their joints condition and general health condition elevate the difficulties in operation and post-surgical recovery.Here, we aimed to simplify the operation procedure by using one-step Total Knee Arthroplasty (TKA) with a stemmed femoral implant. We also investigated if this method could improve the patients' experience after the operation. The surgery including femoral osteotomy and implantation was performed on all fourteen patients by the same orthopedic specialist. The patients' hospitalization time was recorded. The recovery of knee function and patient satisfaction was evaluated by a systematic follow-up with average time 38 months, up to 5 5 years, using Hospital for Special Surgery (HSS) knee scores, the range of motion (ROM), anteroposterior and lateral radiography, and Visual Analog Scale (VAS) scores. The average of hospitalization days was 16 days. No angular deformity, malunion, or shortening were found at radiography.The average ROM was 105.2° at the end of the follow-up period. The knees in all the patients show adequate stability. All patients had returned to their former daily activities. Seventeen out of 24 patients were satisfied with the outcome of the surgery.The usage of TKA with a stemmed femoral implant is a reasonable method for elderly patients suffering from supracondylar femoral fractures and concomitant knee arthritis.

FBXW7 is a potential tumor suppressor that regulates ubiquitination and proteolysis of multiple targets such as cyclin E, c-Myc, c-Jun and Notch. However, little knows about the correlation between FBXW7 and prognosis of patients with colorectal cancer (CRC). In this study, we detected FBXW7 expression in CRC tissue microarray which includes 568 cases cancer tissue and their paired adjacent non-cancerous tissues. We found that FBXW7 expression was significantly reduced in CRC tissues versus paired normal colon tissues ( P < 0.001). Moreover, low FBXW7 expression was significantly associated with increased lymph node metastasis ( P < 0.001) and advanced TNM stage ( P < 0.001). Besides, the low expression of FBXW7 indicated the poor prognosis in CRC patients for both overall and disease-free cumulative survival ( P < 0.001 and P = 0.003, respectively). Multivariate Cox regression analysis showed that low FBXW7 expression was an independent unfavorable prognostic factor of CRC (hazard ratio = 0.45, P = 0.001). In conclusion, we can indicate that FBXW7 may play essential roles in the progression of CRC and function as an independent prognostic marker for clinical diagnosis and therapy treatment of patients with CRC., Competing Interests: None., (IJCEP Copyright © 2018.)

Understanding the mechanism for salt tolerance in wild soybean (Glycine soja) can help researchers improve that trait in cultivated soybean lines. We analyzed the effects of excess NaCl on the growth, physiology, and ion distribution in three soybean species: wild G. soja (W8), semi-wild G. gracilis (SW18), and the cultivated salt-sensitive G. max (cv. Melrose). These comparisons revealed that, under salt stress, shoot and root lengths and biomass (either shoot or root dry weights) were significantly higher for the W8 genotype than for the other two. Most of the morphological parameters for roots from the W8 plants were also increased, including total length, specific root length, and surface area. However, the average root diameter for W8 was significantly lower than that of either SW18 or 'Melrose' soybeans. In response to salinity, photosynthesis was suppressed to a greater extent in 'Melrose' than in W8. The relatively higher tolerance shown by W8 plants was also associated with lower levels of malondialdehyde, hydrogen peroxide, and relative electrical conductivity, but higher activities by superoxide dismutase and peroxidase, as well as more free proline and glycine betaine. In addition, the W8 plants contained less Na + and Cl - , but more K + , and they had a higher K + /Na + ratio in their leaves and roots when compared with either SW18 or 'Melrose' plants. Therefore, the W8 genotype performs better in terms of seedling growth, photosynthetic characteristics, and physiological indexes. These findings provide guidance for developing new soybean cultivars with improved tolerance to salt stress. Our data also contribute to the knowledge base for plant salt tolerance as a tool for increasing the yields of other crops in high-salinity soils.

In plants, resistance (R) genes are involved in pathogen recognition and subsequent activation of innate immune responses. The nucleotide-binding site-leucine-rich repeat (NBS-LRR) genes family forms the largest R-gene family among plant genomes and play an important role in plant disease resistance. In this paper, comprehensive analysis of NBS-encoding genes is performed in the whole Setaria italica genome. A total of 96 NBS-LRR genes are identified, and comprehensive overview of the NBS-LRR genes is undertaken, including phylogenetic analysis, chromosome locations, conserved motifs of proteins, and gene expression. Based on the domain, these genes are divided into two groups and distributed in all Setaria italica chromosomes. Most NBS-LRR genes are located at the distal tip of the long arms of the chromosomes. Setaria italica NBS-LRR proteins share at least one nucleotide-biding domain and one leucine-rich repeat domain. Our results also show the duplication of NBS-LRR genes in Setaria italica is related to their gene structure.

In this study, we isolated a full-length cDNA and named ZmBDF from zea mays. ZmBDF encoded a protein of 356 amino acids and phylogenetic analysis showed that it belongs to a closely related subgroup with B3 domain factors in plants. The transcript level of ZmBDF could be induced by ABA, MeJA, salt or drought treatments. To further investigated the function of ZmBDF, ZmBDF over-expression transgenic lines were got by transforming it into Arabidopsis thaliana. ZmBDF over-expression transgenic plants in Arabidopsis could increase drought and salt tolerant in germination assay. Under drought condition, net photosynthetic rates (PN), stomatal conductance (gs), and internal leaf CO2 concentration (Ci) were less affected in transgenic plants compared with wild type. Besides, the chlorophyll a and chlorophyll b (chl a/chl b) ratio decreased in WT plants than the transgenic plants and total carotenoid content show opposite trends. Moreover, transgenic plants could also reduce the stomatal density and changed the stomatal shape. Taken together, our data suggested that ZmBDF could improve stress tolerance to drought and salt in maize.

The intestinal absorption and metabolism characteristics of the potentially beneficial polyphenol rutin were studied by measuring the intracellular accumulation and transport of rutin into Caco-2 cells with the sensitive and reliable analytical method of HPLC-coupled tandem mass spectrometry. Rutin and glucuronidated rutin were absorbed differently by the basolateral and apical membranes, and rutin showed differential permeability through the apical and basolateral sides. Approximately 33% of the rutin was metabolized to glucuronidated rutin, and the intracellular concentration of glucuronidated rutin was much lower than that of parent rutin. P-glycoprotein and multidrug-resistant proteins 2 and 3 were involved in the transmembrane transport and intracellular accumulation of rutin by Caco-2 cells. These results suggest that a specific transport system mediates rutin movement across the apical membrane in Caco-2 cells and that metabolic enzymes are important for this process.

We demonstrate an innovative technique for the direct measurement on the shear modulus of an individual nanorod. This measurement is based on atomic force microscopy (AFM) and microfabrication techniques. A nanorod is first aligned along the edge of a small trench in a silicon substrate, and then one end of the nanorod is fixed on the substrate. When an AFM tip scans over the nanorod in contact mode, the nanorod will be twisted by the comprehensive action from the force of the AFM tip, confinement from the trench edge and the fixing end. The shear deformation and the corresponding force that caused the deformation can be retrieved from topography and lateral force image, respectively. By small-angle approximation, the shear modulus of the ZnO NR, which has a radius of 166 nm and a length of 4 μm, is measured to be 8.1 ± 1.9 GPa. This method can be applied directly to characterize the shear modulus of any nanowire/nanorod that possesses a polygon cross section.

Vertically aligned ZnO-ZnS heterojunction nanowire (NW) arrays were synthesized by thermal evaporation in a tube furnace under controlled conditions. Both ZnO and ZnS are of wurtzite structure, and the axial heterojunctions are formed by epitaxial growth of ZnO on ZnS with an orientation relationship of [0001](ZnO)//[0001](ZnS). Vertical ZnS NW arrays have been obtained by selectively etching ZnO-ZnS NW arrays. Cathodoluminescence measurements of ZnO-ZnS NW arrays and ZnS NW arrays show emissions at 509 and 547 nm, respectively. Both types of aligned NW arrays have been applied to convert mechanical energy into electricity when they are deflected by a conductive AFM tip in contact mode. The received results are explained by the mechanism proposed for nanogenerator.

Objective: We evaluated antioxidative effect of two antioxidative strains, isolated from the traditional fermented dairy products., Methods: Both intact cells and cell-free extract of Lactobacillus casei subsp. casei SY13 and Lactobacillus delbrueckii subsp. bulgaricus LJJ were used to study the inhibited effect of linoleic acid peroxidation, the ability of scavenging 1,1-diphenyl-2-picrylhydrazyl radical, hydroxyl radical, superoxide anion radical,the ability of tolerancing hydrogen peroxide and the chelating capacity of ferrous ion and reducting activity., Results: Lactobacillus casei subsp. casei SY13 and Lactobacillus delbrueckii subsp. bulgaricus LJJ demonstrated highest inhibition on linoleic acid peroxidation by 62.95% and 66.16%, respectively. The cell-free extract showed excellent scavenging superoxide anion and hydroxyl radicals activity. However, the intact cells of Lactobacillus delbrueckii subsp. bulgaricus LJJ scavenging superoxide and hydroxyl radicals capacity were not detected. The intact cells of Lactobacillus casei subsp. casei SY13 and Lactobacillus delbrueckii subsp. bulgaricus LJJ on 1,1-diphenyl-2-picrylhydrazyl radical scavenging ability and chelating ferrous ion capacity were superior to cell-free extract. The highest reduced activety was equivalent to 305 micromol/L and 294 micromol/L L-cysteine., Conclusion: Two latobacilli strains had good antioxidant capacity. As potential probiotics, it can be used in future.

Objective: To evaluate the clinical outcome of free vascularized fibular associated with iliac graft in treatment of old femoral neck fracture., Methods: From January 1994 to January 1997, 76 cases of old femoral neck fracture were treated with free vascularized fibular associated with iliac graft, including 54 males and 22 females, aging from 24 to 48 years with an average of 31.5 years. All of these fractures resulted from injury. There were 20 cases of Garden II, 41 of Garden III and 15 of Garden IV. Based on the location of fracture, there was 26 cases of subcapital, 42 cases of transcervical and 8 cases of basal. Sixty-five cases were treated with internal fixation, 7 cases with skin traction and 4 just with staying in bed. Their Harris score were from 52 to 72 with an average of 65.6. The time from injury to operation was 2-24 months. The size of free vascularized fibular was 6-8 cm and iliac graft was 3.0 cm x 2.0 cm x 1.5 cm., Results: In 76 cases, 68 were followed up and all fractures healed within 4 to 6 months with an average of 5.2 months. The increased density in femoral head was observed 1 year after operation. After 10 years of operation normal hip function was achieved in 63 cases followed up 10.1-12.4 years with the average as 10.5 years); the Harris score was 87.5 (84 to 94). The structure of femoral head was normal and the grafted fibular and iliac bone healed with the femoral, no elapse or cyst occurred. Five cases had been complied with total hip replacement for femoral head necrosis or other., Conclusion: Free vascularized fibular associated with iliac graft is a good method to treat old femoral neck fracture.

We have studied the piezoelectric potential output of a ZnO wire/belt functionalized with p-type oligomer (2,5-Bis(octanoxy)-1,4-bis(4-formyl phenylene vinylene) benzene) (OPV2) when it was deflected by an atomic force microscope (AFM) tip in contact mode. In comparison to the ZnO wire/belt without oligomer coating, an extra positive voltage peak was observed prior to the appearance of a negative potential peak. The paired positive and negative voltage peaks are the results of tip contact to the stretched and the compressed side of the wire/belt, corresponding to the positive and negative local piezoelectric potential, respectively. The p-n junction between OPV2 and ZnO serves as a "diode" that controls the flow of current. When the nanowire/nanobelt is first bent by the AFM tip, the diode is reversely biased and the piezoelectric charges are stored in the ZnO wire/belt. As the AFM tip further bends the wire/belt, the local piezoelectric potential is continuously accumulated to a value that is large enough to break through the diode. Then the free charges from the external circuit can flow in and neutralize/screen part of the piezoelectric charges, resulting in a positive pulse in the output signal. When the AFM tip continues to scan to reach the compressed side of the ZnO wire/belt, the p-n junction is forwardly biased. Neutralizing/screening the residual and the newly created piezoelectric charges leads to the flow of current from the tip to the ZnO wire/belt, resulting in a negative voltage pulse. This study supports the charging and discharging model proposed for the piezoelectric nanogenerator.

By assembling a ZnO nanowire (NW) array based nanogenerator (NG) that is transparent to UV light, we have investigated the performance of the NG by tuning its carrier density and the characteristics of the Schottky barrier at the interface between the metal electrode and the NW. The formation of a Schottky diode at the interface is a must for the effective operation of the NG. UV light not only increases the carrier density in ZnO but also reduces the barrier height. A reduced barrier height greatly weakens the function of the barrier for preserving the piezoelectric potential in the NW for an extended period of time, resulting in little output current. An increased carrier density speeds up the rate at which the piezoelectric charges are screened/neutralized, but a very low carrier density prevents the flow of current through the NWs. Therefore, there is an optimum conductance of the NW for maximizing the output of the NG. Our study provides solid evidence to further prove the mechanism proposed for the piezoelectric NG and piezotronics. The output current density of the NG has been improved to 8.3 microA/cm2.

An effective, low cost, simple, and mask-free pathway is demonstrated for achieving density control of the aligned ZnO nanowires grown for large-scale applications. By a slight variation of the thickness of the thermally evaporated gold catalyst film, a significant change in the density of aligned ZnO nanowires has been controlled. The growth processes of the nanowires on an Al(0.5)Ga(0.5)N substrate has been studied based on the wetting behavior of gold catalyst with or without source vapor, and the results classify the growth processes into three categories: separated dots initiated growth, continuous layer initiated growth, and scattered particle initiated growth. This study presents an approach for growing aligned nanowire arrays on a ceramic substrate with the simultaneous formation of a continuous conducting electrode at the roots, which is important for device applications, such as field emission.

We have converted nanoscale mechanical energy into electrical energy by means of piezoelectric zinc oxide nanowire (NW) arrays. The aligned NWs are deflected with a conductive atomic force microscope tip in contact mode. The coupling of piezoelectric and semiconducting properties in zinc oxide creates a strain field and charge separation across the NW as a result of its bending. The rectifying characteristic of the Schottky barrier formed between the metal tip and the NW leads to electrical current generation. The efficiency of the NW-based piezoelectric power generator is estimated to be 17 to 30%. This approach has the potential of converting mechanical, vibrational, and/or hydraulic energy into electricity for powering nanodevices.

Vertically aligned single-crystal ZnO nanorods have been successfully fabricated on semiconducting GaN, Al0.5Ga0.5N, and AlN substrates through a vapor-liquid-solid process. Near-perfect alignment was observed for all substrates without lateral growth. Room-temperature photoluminescence measurements revealed a strong luminescence peak at approximately 378 nm. This work demonstrates the possibility of growing heterojunction arrays of ZnO nanorods on AlxGa1-xN, which has a tunable band gap from 3.44 to 6.20 eV by changing the Al composition from 0 to 1, and opens a new channel for building vertically aligned heterojunction device arrays with tunable optical properties and the realization of a new class of nanoheterojunction devices.

Objective: To explore the expression of IL-8 on laryngeal carcinoma and the edge tissues and its relationship with the character of laryngeal carcinoma., Method: Immunohistochemical SABC detections were carried out in 35 case of original laryngeal cancer and the edge tissues (1.0 cm near the tumor)., Result: The positive rate was 68.6% in 24 case of carcinoma group, 42.9% in 15 case of edge group. The statistical difference between carcinoma group with edge group was very significant(P < 0.05). The expression of IL-8 had no difference in location, tumor developed degree and lymph metastases., Conclusion: The expression of IL-8 may play an important role in the process of laryngeal cancer and the patients' immune stage.