Predicting distant metastasis in nasopharyngeal carcinoma using gradient boosting tree model based on detailed magnetic resonance imaging reports.

BACKGROUND: Development of distant metastasis (DM) is a major concern during treatment of nasopharyngeal carcinoma (NPC). However, studies have demonstrated improved distant control and survival in patients with advanced NPC with the addition of chemotherapy to concomitant chemoradiotherapy. Therefore, precise prediction of metastasis in patients with NPC is crucial. AIM: To develop a predictive model for metastasis in NPC using detailed magnetic resonance imaging (MRI) reports. METHODS: This retrospective study included 792 patients with non-distant metastatic NPC. A total of 469 imaging variables were obtained from detailed MRI reports. Data were stratified and randomly split into training (50%) and testing sets. Gradient boosting tree (GBT) models were built and used to select variables for predicting DM. A full model comprising all variables and a reduced model with the top-five variables were built. Model performance was assessed by area under the curve (AUC). RESULTS: Among the 792 patients, 94 developed DM during follow-up. The number of metastatic cervical nodes (30.9%), tumor invasion in the posterior half of the nasal cavity (9.7%), two sides of the pharyngeal recess (6.2%), tubal torus (3.3%), and single side of the parapharyngeal space (2.7%) were the top-five contributors for predicting DM, based on their relative importance in GBT models. The testing AUC of the full model was 0.75 (95% confidence interval [CI]: 0.69-0.82). The testing AUC of the reduced model was 0.75 (95%CI: 0.68-0.82). For the whole dataset, the full (AUC = 0.76, 95%CI: 0.72-0.82) and reduced models (AUC = 0.76, 95%CI: 0.71-0.81) outperformed the tumor node-staging system (AUC = 0.67, 95%CI: 0.61-0.73). CONCLUSION: The GBT model outperformed the tumor node-staging system in predicting metastasis in NPC. The number of metastatic cervical nodes was identified as the principal contributing variable.

Dual-layer optical encryption fluorescent polymer waveguide chip based on optical pulse-code modulation technique.

Information encryption technique has broad applications in individual privacy, military confidentiality, and national security, but traditional electronic encryption approaches are increasingly unable to satisfy the demands of strong safety and large bandwidth of high-speed data transmission over network. Optical encryption technology could be more flexible and effective in parallel programming and multiple degree-of-freedom data transmitting application. Here, we show a dual-layer optical encryption fluorescent polymer waveguide chip based on optical pulse-code modulation technique. Fluorescent oligomers were doped into epoxy cross-linking SU-8 polymer as a gain medium. Through modifying both the external pumping wavelength and operating frequency of the pulse-code modulation, the sender could ensure the transmission of vital information is secure. If the plaintext transmission is eavesdropped, the external pumping light will be switched, and the receiver will get warning commands of ciphertext information in the standby network. This technique is suitable for high-integration and high-scalability optical information encryption communications.

New insights into the occurrence of continuous cropping obstacles in pea (Pisum sativum L.) from soil bacterial communities, root metabolism and gene transcription.

BACKGROUND: Continuous cropping is a significant obstacle to sustainable development in the pea (Pisum sativum L.) industry, but the underlying mechanisms of this remain unclear. In this study, we used 16 S rDNA sequencing, transcriptomics, and metabolomics to analyze the response mechanism of roots and soil bacteria to continuous cropping and the relationship between soil bacteria and root phenotypes of different pea genotypes (Ding wan 10 and Yun wan 8). RESULTS: Continuous cropping inhibited pea growth, with a greater effect on Ding wan 10 than Yun wan 8. Metabolomics showed that the number of differentially accumulated metabolites (DAMs) in pea roots increased with the number of continuous cropping, and more metabolic pathways were involved. Transcriptomics revealed that the number of differentially expressed genes (DEGs) increased with the number of continuous cropping. Continuous cropping altered the expression of genes involved in plant-pathogen interaction, MAPK signal transduction, and lignin synthesis pathways in pea roots, with more DEGs in Ding wan 10 than in Yun wan 8. The up-regulated expression of genes in the ethylene signal transduction pathway was evident in Ding wan 10. Soil bacterial diversity did not change, but the relative abundance of bacteria significantly responded to continuous cropping. Integrative analysis showed that the bacteria with significant relative abundance in the soil were strongly associated with the antioxidant synthesis and linoleic acid metabolism pathway of pea roots under continuous cropping once. Under continuous cropping twice, the bacteria with significant relative abundance changes were strongly associated with cysteine and methionine metabolism, fatty acid metabolism, phenylpropanoid biosynthesis, terpenoid backbone biosynthesis, linoleic acid, and amino sugar and nucleotide sugar metabolism. CONCLUSION: Ding wan 10 was more sensitive to continuous cropping than Yun wan 8. Continuous cropping times and pea genotypes determined the differences in root metabolic pathways. There were common metabolic pathways in the two pea genotypes in response to continuous cropping, and the DEGs and DAMs in these metabolic pathways were strongly associated with the bacteria with significant changes in relative abundance in the soil. This study provides new insights into obstacles to continuous cropping in peas.

Magnetic biochar based on furfural residue as an excellent candidate for efficient adsorption of Tetracycline, Bisphenol A, Congo red, and Cr6.

Magnetic porous adsorbent materials are widely favored for their large specific surface area, good adsorption performance, and ease of separation. This work provided a magnetic biochar derived from furfural residue (M-FRAC) with excellent adsorption properties for various pollutants, including Congo red (CR), Tetracycline (TC), Bisphenol A (BPA), and Cr6+. The influence of experimental parameters, such as pollutant concentration, contact time, and pH, on the adsorption properties of M-FRAC was studied in detail. The adsorption process was highly dependent on pH and initial contaminant concentration. All pollutant adsorption was favorable under acidic conditions. The optimal pH of the CR, TC, and Cr6+ adsorption was 5, 4, and 2, respectively, while that of BPA was in the range of 2-5. The experimental equilibrium adsorption amount of CR, TC, BPA, and Cr6+ by M-FRAC was 110.89, 602.81, 157.76, and 265.31 mg/g, respectively. The adsorption processes of pollutants on M-FRAC were in accordance with the Langmuir isotherm model. The adsorption kinetics fitted the pseudo-second-order (PSO) kinetics model. In addition, M-FRAC could be readily separated from solution by applying an external magnetic field. Therefore, the M-FRAC has a good application prospect in practical industrial wastewater treatment.

Metal-printing tunable interlayer waveguide coupler using low-loss fluorinated polycarbonate.

Tunable three-dimensional (3D) integrated optical waveguide chips with optical interconnection function are beneficial to expand the application of optical devices in a 3D integrated photonic module. Here, we propose a thermo-optic (TO) tunable interlayer waveguide coupler based on the metal-printing technique. Low-loss fluorinated polycarbonate (AF-Ali-PC MA) and poly (methyl methacrylate-glycidyl methacrylate) [P(MMA-co-GMA)] are synthesized as waveguide core and cladding layer, respectively. The thermal stability and optical adsorption characteristics of AF-Ali-PC MA are analyzed. Optical signal transmission features of the interlayer coupling waveguides are simulated. The optical response properties and fabrication process flows of a dynamic multilayer waveguide chip can be greatly improved by the metal-printing technique. The on-off time of the TO interlayer coupling chip is obtained as 250 µs, and the electrical power consumption is measured as 7.6 mW. To the best of our knowledge, this is the first time that a TO tunable interlayer waveguide coupler is achieved by an efficient metal-printing method, which is suitable for large-scale photonic integrated circuit (PIC) systems and multilayer optical interconnection (OXC) networks.

[Simulation of the responses of spring wheat yield to the rates and depths of nitrogen application in dryland based on APSIM model]. / 基于APSIM模型的旱地春小麦产量对施氮量和施氮深度的响应模拟.

Nitrogen limitation is an important factor for the improvement of crop water production potential in rain-fed areas of the Loess Plateau. The reasonable deep application of nitrogen fertilizer is a promising method to increase yield of rain-fed crop. Based on APSIM model, this study simulated spring wheat yield under different nitrogen application rates and depths, by using meteorological observation data from 1990 to 2020 in the semiarid areas of central Gansu Province, aiming to provide theoretical reference for optimizing wheat fertilization strategy. The results showed that the determination coefficient of simulated spring wheat yield, biomass and soil water content in 0-200 cm soil profile was greater than 0.80, the normalized root mean square error was less than 0.2, and the model validity index was greater than 0.5. These results indicated that the model had good fitting and adaptability in the test area. Across all the levels within the experimental design, increasing nitrogen application rates could significantly increase the yield of spring wheat in different precipitation years, and increasing nitrogen application depth could significantly increase spring wheat yield in wet and normal years, but had no effect in dry years. The rate and depth of nitrogen application had significant interaction effects on spring wheat yield in wet and normal years, but not in dry years. According to the binary quadratic regression fitting equation, when the potential maximum yield reached 2749 kg·hm-2 in wet year, nitrogen application depth was 22.7 cm, and nitrogen application rate was 245 kg·hm-2. When the maximum potential yield reached 2596 kg·hm-2 in normal year, nitrogen application depth was 20.6 cm, and nitrogen application rate was 235 kg·hm-2. Integrating the effects of nitrogen application rate and depth on yield, biomass and agronomic efficiency of nitrogen fertilizer, and farmer's fertilizer application habits, the recommended nitrogen application depth was 20-23 cm, and nitrogen application amount was 120-150 kg·hm-2, which could further improve water productivity and nitrogen use efficiency of spring wheat in arid areas of central Gansu Province.

Optical Waveguide Sensors for Measuring Human Temperature and Humidity with Gel Polymer Electrolytes.

In this work, multimodal responsive optical waveguide sensors using a stable cross-linking gel polymer electrolyte are successfully designed and fabricated by bottom metal-printing technology. Temperature and humidity sensing characterization based on the polymer electrolyte is simulated and analyzed. The multimodal responsive properties of the photonic chip are defined based on the analysis of ion relaxation dynamics: optical phase variable to monitor temperature and optical attenuation variable to detect humidity. In the supervising temperature (36.0-38.0 °C) and relative humidity (45-65%) range, the temperature and humidity sensitivities of the device are measured as 0.5π rad/°C and 1.14 dB/% RH, respectively. The fast-response time for both temperature and humidity of the multifunctional sensor can be obtained as 4.21 ms and 1.32 s, respectively. These findings provide a feasible scheme for the design and application of temperature and humidity sensors in potential medical treatment. From gel polymer electrolytes to multimode monitoring applications, the application exploration of high stability and ultrafast response multimode waveguide sensors is gradually being carried out. This study has great significance for the comprehensive monitoring of sophisticated human physical signs by multimodal responsive waveguide sensors.

A novel worm-like micelles@MOFs precursor for constructing hierarchically porous CoP/N-doped carbon networks towards efficient hydrogen evolution reaction.

Constructing electrocatalysts with plentiful active sites, great mass transfer ability, and high electrical conductivity is critical to realize efficient hydrogen evolution reaction (HER). Hierarchically porous cobalt phosphide/N-doped nanotubular carbon networks (CoP/NCNs) that have all the features were fabricated in this work. For the fabrication, the polymeric worm-like micelles (PWs) with a large aspect ratio were coated by a uniform nanolayer of Zn-Co zeolitic imidazolate frameworks (Zn-Co-ZIFs) on their surface, resulting in the hybrid nanofibers PWs@Zn-Co-ZIFs (HPWs). Inheriting the randomly curved and entanglement properity of PWs, the rigid HPWs formed hybrid networks with the packing voids sized tens to 200 nm. Then, the hybrid networks were treated by pyrolysis-oxidation-phosphidation and ZnO-removal processes, leading to the hierarchically porous CoP/NCNs. In the CoP/NCNs, there are plentiful CoP nanoparticles embedded on the surface of conductive carbon network and fully exposed. When used for HER electrocatalyst, the CoP/NCNs only need small overpotentials (98 and 118 mV in acid and alkaline electrolyte) at 10 mA cm-2. This novel strategy is instructive for tailoring hierarchically porous transition metal phosphide/carbon nanocomposites as promising electrocatalysts.

[Effects of vertical rotary subsoiling with combined organic and inorganic fertilization on water use efficiency and yield of forage maize in a semi-arid area.] / åŠå¹²æ—±åŒºç«‹å¼æ·±æ—‹è€•å’Œæœ‰æœºæ— æœºè‚¥é æ–½å¯¹é¥²ç”¨çŽ‰ç±³æ°´åˆ†åˆ©ç”¨æ•ˆçŽ‡å’Œäº§é‡çš„å½±å“.

Both reasonable soil tillage and fertilization management play critical roles in improving the yield and water use efficiency (WUE) of forage maize in the semi-arid area of Loess Plateau. A field experiment was conducted at Dingxi experimental station of Gansu Academy of Agricultural Sciences between 2017 and 2019. We explored the effects of tillage method and fertilization type on yields and WUE of forage maize, as well as the economic benefits. There were four treatments in the experiment, including traditional rotary tillage + organic-inorganic fertilization (TOF), deep rotary tillage + organic-inorganic fertilization (DOF), and vertical rotary subsoiling + organic-inorganic fertilization (VROF), and the traditional rotary tillage + inorganic fertilization as the control (TF). Our results showed that, compared with DOF, TOF, TF, and VROF all decreased soil water storage in 0-300 cm soil layer at flowering stage, ranging from 16.9 mm to 79.9 mm, but they all increased soil water consumption by 9.7-22.4 mm during vegetative growing stages, 11.0-19.8 mm during reproductive stage in the dry years. Due to significant improvement in water absorption, VROF increased dry matter weight at maturity by 3.9%-13.4% compared to other treatments. Similarly, plant height, ear length, grain number per ear, 100-grain weight, and double ear rate under VROF were significantly increased, while bald head length was decreased significantly, when compared with other treatments. As a result, over the three experimental seasons, VROF increased the grain and biological yield by 4.3%-51.5% and 4.3%-25.7% compared to other treatments, respectively. Accordingly, WUE calculated by grain and biomass yields were increased by 2.7%-36.9% and 3.6%-13.5% under VROF, compared to other treatments. VROF increased the unit gross total output value and the net income by 5.1%-32.9% and 6.9%-80.5% respectively, compared to other treatments. These results demonstrated that VROF is a drought-resistant and yield-increasing farming technology for sustainable forage maize production in the semi-arid area of the Loess Plateau, Northwest China.

[Effects of micro-ridge-furrow with plastic mulching and bunching seeding on soil hydrothermal environment and its response to photosynthesis and grain yield of spring wheat]. / å ¨è†œå¾®åž„æ²Ÿç©´æ’­å¯¹æ˜¥å°éº¦åœŸå£¤æ°´çƒ­çŽ¯å¢ƒçš„å½±å“åŠå ¶å ‰åˆå’Œäº§é‡æ•ˆåº”.

The relieving of drought and cold restriction on spring wheat development is one of the key factors increasing wheat yield in arid areas of central Gansu Province. A field experiment with spring wheat (Longchun No. 35) was carried out in central Gansu Province from 2016 to 2018. There were three treatments: 1) micro-ridge-furrow with whole field plastic mulching and bunching seeding (PRF), 2) whole field soil plastic mulching and bunching seeding (PMS), 3) bunching seeding without mulching (CK). We measured soil temperature in 0-25 cm profile, soil water content in 0-300 cm profile, leaf SPAD, photosynthetic rate, transpiration rate, aboveground biomass in different growth stages, and grain yield to understand the effect of PRF on soil hydrothermal environment, spring wheat yield and water use efficiency (WUE) from the aspect of soil hydrothermal, canopy development and grain yield. The results showed that mean soil temperature in 0-25 cm profile of PRF and PMS increased by 2.8 ℃ and 2.5 ℃ at the seedling stage, decreased by 1.4 ℃ and 0.9 ℃ from filling to maturity stage, respectively. Soil water storage in 0-300 cm profile of PRF and PMS increased by 59.7 mm and 41.8 mm from sowing to seedling stage. Water consumption of PRF and PMS increased by 46.1 mm and 39.8 mm from seedling to filling stage. PRF increased average soil temperature in 0-25 cm profile by 0.3 ℃ at seedling stage, but decreased by 0.5 ℃ from filling to maturity stage, and increased soil water storage in 0-300 cm profile by 18.0 mm from sowing to seedling stage. PMF increased water consumption by 13.0 mm from booting to maturing stage, as compared with PMS. Based on the optimizated soil hydrothermal conditions, leaf SPAD value, aboveground biomass, net photosynthetic rate, and transpiration rate of PRF increased, as compared with PMS and CK. The PRF increased grain yield by 9.1% and 36.5%, WUE by 5.9% and 30.8% compared to PMS and CK, respectively. Consequently, PRF increased soil temperature at wheat seedling stage, reduced it from filling to maturing stage, improved wheat water consumption from sowing to filling stage, increased leaf SPAD value and aboveground biomass, promoted photosynthetic function in leaf from seedling to filling stage, and consequently led to increased yield and water utilization. Such effects were more significant in dry year (2016 and 2017).

[Effects of organic fertilizer application on flag leaf C/N ratio, photosynthetic characteristics and yield of spring wheat with full plastic film mulching]. / å ¨è†œè¦†åœŸä¸‹æ–½æœ‰æœºè‚¥å¯¹æ˜¥å°éº¦æ——å¶ç¢³æ°®æ¯”ã€å ‰åˆç‰¹æ€§å’Œäº§é‡çš„å½±å“.

A field experiment was conducted in the rain-fed semi-arid region of central Gansu in 2016 and 2017, with the treatments 1) hill-drop flat planting with full plastic film mulching (PMS), 2) hill-drop flat planting with full plastic film mulching plus organic fertilizers (PMO), and 3) hill-drop flat planting without soil mulching (CK). We investigated the relations among soil moisture, photosynthetic rate (Pn), stomatal conductance (gs) and transpiration rate (Tr), C/N ratio, and total nitrogen of flag leaf from the heading stage to the seed-filling stage in different treatments to probe into their effects on the yield and yield components of spring wheat variety 'Longchun 27'. The results showed that organic fertilizer application could increase soil moisture at the middle and late growth stages of spring wheat. PMO increased soil water storage in 0-300 cm depth from the heading stage to the seed filling stage by 4.6% and 8.5%, decreased population canopy temperature by 0.1-1.3 ℃ and 1.4-4.9 ℃, increased net photosynthetic rate of flag leaf by 9.3% and 29.7%, stomatal conductance by 30.9% and 103.8%, transpiration rate by 5.1% and 55.0%, total nitrogen content by 6.6% and 18.9%, and decreased C/N ratio by 6.4% and 22.8%, respectively. Compared with PMS and CK, PMO significantly improved grain number per spike and 1000-grain weight, and increased grain yield by 9.1% and 53.7%, respectively. From the heading stage to filling stage, the Pn and gs of flag leaf had negative correlation with C/N, while C/N was negatively correlated with grain yield. Consequently, PMO could improve soil water storage and promote photosynthesis of flag leaf, reduce the intensity of physiological drought stress and the limitations of nitrogen absorption and assimilation in flag leaf from the heading stage to the seed-filling stage, and increase grain number and grain weight and consequently the yield of spring wheat in semi-arid region.

Bottom-metal-printed thermo-optic waveguide switches based on low-loss fluorinated polycarbonate materials.

In this work, thermo-optic (TO) waveguide switches are designed and fabricated based on the bottom-metal-printed technique. Low-loss fluorinated polycarbonate (AF-Z-PC MA) and polymethyl methacrylate (PMMA) are used as core and cladding materials, respectively. The thermal stability and optical absorption characteristics of AF-Z-PC MA are analyzed. The optical and thermal field distributions of the TO switch are simulated. The insertion loss and extinction ratio of the device are found to be 4.5 dB and 19.8 dB, respectively, at a wavelength of 1550 nm. The on-off time of the switching chip is 80 µs. The electrical power consumption is approximately 8.8 mW. The proposed low-loss fluorinated polymer TO waveguide switch realized by bottom-metal-printed fabrication technology is suitable for large-scale integrated photonic circuit systems.

[Effects of optimal nitrogen fertilizer management on water and fertilizer utilization efficiency and yield under double-ridge-furrow sowing with the whole plastic film mulching in maize in a semi-arid area]. / åŠå¹²æ—±åŒºæ°®è‚¥è¿ç­¹å¯¹å ¨è†œåŒåž„æ²Ÿæ’­çŽ‰ç±³æ°´è‚¥åˆ©ç”¨å’Œäº§é‡çš„å½±å“.

Improper fertilization style is one of the main reasons for low water and fertilizer use efficiency of double-ridge-furrow sowing with the whole plastic film mulching in maize production in the semi-arid area. Understanding the effects of reduction, postponing, and organic fertilizer substitution of nitrogen fertilizer on water and fertilizer use efficiency and yield of maize can provide theore-tical basis for effective management of water and fertilizer in maize production. Based on a 4-year field experiment with three treatments: all fertilizers as base fertilizer under double-ridge-furrow sowing with the whole plastic film mulching (CK), nitrogen fertilizer reduced by 15% and topdres-sing in tasseling stage (RN), 30% of the chemical fertilizer replaced by organic fertilizer and topdressing in tasseling stage (RNM), we measured water consumption characteristics, growth and development, water and fertilizer utilization efficiency of maize. The results showed that fertilization pattern significantly affected water and fertilizer utilization efficiency and yield of maize, which was dependent on annual rainfall. In dry and normal rainfall year, water consumption in pre-flowering stage of RN was decreased by 16.1%-18.8% and that in post-flowering stage was increased by 18.0%-22.2%, while water consumption in pre-flowering and post-flowering stages of RNM did not differ from that in CK. In wet year, water consumption in pre-flowering stage of RN and RNM was decreased by 16.7% and 6.3%, while that in post-flowering stage was increased by 11.4% and 29.7%, respectively. Compared with CK, RN significantly increased the relative content of chlorophyll (SPAD) of maize leaves after topdressing, the biomass in post-flowering stage was increased by 15.6%-44.9%, the ear length, the number and weight of grains per spike and the 100-grain weight were increased significantly, yield was increased by 9.8%-17.0%, and water use efficiency (WUE) was increased by 6.3%-21.4%, with the partial productivities of fertilizer (PEPT), N (PEPTN), P (PEPTP) and K (PEPTK) were all increased significantly. In conclusion, RN could improve water consumption and the SPAD value in post-flowering stage of maize in different precipitation years, increase post-flowering biomass, and optimize the ear character, obviously improve yield, water and fertilizer use efficiency. It was a effective fertilizer management mode with high-efficiency utilization of water and fertilizer under double-ridge-furrow sowing with the whole plastic film mulching in maize in the semi-arid area.

[Effects of annual whole-film mulching on freezing-thawing characteristics, moisture, and temperature distribution of maize soil in semi-arid area]. / åŠå¹²æ—±åŒºå‘¨å¹´å ¨è†œè¦†ç›–å¯¹çŽ‰ç±³ç”°åœŸå£¤å†»èžç‰¹æ€§å’Œæ°´çƒ­åˆ†å¸ƒçš„å½±å“.

Based on a 3-year field experiment (2015-2017) with two treatments, annual whole-film mulching (PM) and uncovered (CK), we analyzed the relationship between soil temperature, moisture, and soil hydrothermal movement in semi-arid area. The results showed that freezing-thawing processes under both PM and CK were one-way freezing and two-way melting. Compared with CK, the freezing period in PM treatment was lagged, freezing rate was slowed down, freezing depth was 20 cm shallower, but melting rate was faster, and melting period was shortened by 6-7 days. In freezing period, soil temperature gradients of PM and CK were positive, with heat being transmitted toward top soil layer, and the conduction strength in PM treatment was greater than CK. During the melting period, soil temperature gradient of PM was also positive, with heat being transmitted toward upper soil layer, and that of CK was conversed. Soil water in PM treatment transported to upper soil layer during freezing-thawing period, but it appeared a "down-up-down" movement mode under CK in freezing period, "up-down" in thawing period. There was positively correlation between temperature and moisture gradient in the freezing period under both PM and CK treatments, with closer correlation in PM than CK. During melting period, soil temperature and moisture gradient was positively correlated in PM treatment with soil heat and moisture moved upward synchronously, while that in CK was negatively correlated with soil heat and moisture simultaneously moved to the lower layer soil. Driven by soil temperature and moisture gradient, soil temperature in 0-10 cm, 10-20 cm and 20-30 cm layers increased by 1.13-1.34 ℃, 0.96-1.24 ℃ and 0.89-1.32 ℃, while average soil water content increased by 3.4%-5.6%, 1.4%-2.2% and 6.7%-7.8%, respectively in PM treatment before sowing. Our results indicated that PM could provide water and heat protection for re-greening of winter crop and sowing, emergence and seedling of spring-sown crops in semi-arid areas.

Metal-printing polymer waveguide thermo-optic switches compatible with 650 and 532 nm visible signal wavelengths for plastic optical fiber systems.

In this work, thermo-optic (TO) waveguide switches for 650 and 532 nm visible wavelengths are designed and fabricated by the metal-printing technique based on poly (methyl methacrylate-glycidyl methacrylate) [P(MMA-GMA)] material. The optical characteristics and thermal stability of the P(MMA-GMA) material are analyzed. Optical transmission modes in the core waveguide for different visible wavelengths are simulated, and the thermal field distribution from the self-heating electrode structure is calculated, respectively. The structural parameters of the devices compatible with 650 and 532 nm visible wavelengths are designed optimally. For 650 and 532 nm signal wavelengths, the insertion loss of the actual TO switch fabricated is less than 3.2 dB, and the response time of the device is about 367.4 µs at 100 Hz square wave electrical signals. The driving electrical power of the device for the 650 nm signal wavelength is 15.2 mW and 14.0 mW for the 532 nm signal wavelength, respectively. The extinction ratio of the visible TO switch for 650 nm is 15.1 dB and 18.5 dB for 532 nm, respectively. The technique is suitable for realizing plastic optical fiber system applications.

NIR-Induced Disintegration of CuS-Loaded Nanogels for Improved Tumor Penetration and Enhanced Anticancer Therapy.

Nanocarrier-based cancer therapy suffers from poor tumor penetration and unsatisfied therapeutical efficacy, as its vascular extravasation efficiency is often compromised by the intrinsic physiological heterogeneity in tumor tissues. In this work, novel near infrared (NIR)-responsive CuS-loaded nanogels are prepared to deliver anticarcinogen into the tumor. These hybrid polymeric nanogels possess high photothermal conversion efficiency, and are able to load a large amount of antitumor drug (e.g., doxorubicin [DOX]). More importantly, the thermal heat could induce self-destruction of the big-size framework of hybrid nanogels into small nanoparticles, which greatly facilitates tumor penetration to release DOX deep inside the tumor, as validated by photoacoustic (PA) imaging which exhibits 26.3 times enhancement at the interior region compared to signals of groups without laser irradiation. Such structural alteration, combined with strong photothermal and chemotherapy effects, leads to remarkable inhibition of tumor growth in mice. As a result, this NIR-induced disintegration of CuS-loaded nanogels provides a novel drug delivery strategy and might open a new window for clinical cancer treatment.

[Effects of nitrogen application and elevated atmospheric CO2 on electron transport and energy partitioning in flag leaf photosynthesis of wheat].

Wheat (Triticum aestivum) plants were pot-cultured in open top chambers at the nitrogen application rate of 0 and 200 mg x kg(-1) soil and the atmospheric CO2 concentration of 400 and 760 micromol x mol(-1). Through the determination of flag leaf nitrogen and chlorophyll contents, photosynthetic rate (Pn)-intercellar CO2 concentration (Ci) response curve, and chlorophyll fluorescence parameters at heading stage, the photosynthetic electron transport rate and others were calculated, aimed to investigate the effects of nitrogen application and elevated atmospheric CO2 concentration on the photosynthetic energy partitioning in wheat flag leaves. Elevated atmospheric CO2 concentration decreased the leaf nitrogen and chlorophyll contents, compared with the ambient one, and the chlorophyll a/b ratio increased at the nitrogen application rate of 200 mg x kg(-1). With the application of nitrogen, no evident variations were observed in the maximal photochemical efficiency (Fv/Fm), maximal quantum yield under irradiance (Fv'/Fm') of PS II reaction center, photochemical fluorescence quenching coefficient (q(p)), and actual PS II efficiency under irradiance (phi(PS II) at elevated atmospheric CO2 concentration, and the total photosynthetic electron transport rate (J(F)) of PS II reaction center had no evident increase, though the non-photochemical fluorescence quenching coefficient (NPQ) decreased significantly. With no nitrogen application, the Fv'/Fm', psi(PS II), and NPQ at elevated atmospheric CO2 concentration decreased significantly, and the J(F) had a significant decrease though the Fv/Fm and q(p) did not vary remarkably. Nitrogen application increased the J(F) and photochemical electron transport rate (Jc); while elevated atmospheric CO2 concentration decreased the photorespiration electron transport rate (J0), Rubisco oxidation rate (V0), ratio of photorespiration to photochemical electron transport rate (J0/Jc) , and Rubisco oxidation/carboxylation rate (Vo/Vc), but increased the photochemical electron transport rate (Jc) and Rubisco carboxylation rate (Vc). It was concluded that elevated atmospheric CO2 concentration decreased the leaf nitrogen and chlorophyll contents, while nitrogen application increased the photosynthetic electron transport rate of PS II reaction center significantly, and promoted the photosynthetic electron flow towards photochemistry, making more photosynthetic electron take part in Rubisco carboxylation and leading to the significant increase of Pn.

[Effects of whole field-surface plastic mulching and planting in furrow on soil temperature, soil moisture, and corn yield in arid area of Gansu Province, Northwest China].

Taking spring corn (Zea mays) cultivar Shendan 16 as test material, a field experiment was conducted to study the effects of the treatments whole-field surface plastic mulching and planting in furrow (PMF), whole-field surface sand mulching and flat planting (SM), and uncovered and flat planting (CK) on the soil temperature, soil moisture, and corn yield on the dry land of arid area (annual average precipitation 415 mm) in middle Gansu Province. Comparing with CK, treatments PMF and SM increased the average temperature in 0-25 cm soil layer before tasselling stage, with the highest increment in treatment PMF. As for the soil water consumption, its depth in the three treatments increased with increasing years of planting. In the first year of planting, the soil water consumption was the most in 20-120 cm soil layer; whereas in the second year, the consumption was the most in 120-200 cm soil layer, with the soil water loss being the highest in treatment PMF. Treatment PMF had the highest grain number, grain weight per spike, and 100-grain weight, followed by treatment SM, and CK. In 2009 and 2010, the average grain number, average grain weight per spike, and average 100-grain weight in treatment PMF were increased by 13.5% and 114.2%, 29.8% and 321.1%, and 14.4% and 95.4% respectively, as compared to treatments SM and CK, and the grain yield and water use efficiency in treatments PMF and SM were increased by 333.1% and 240.2%, and 290.6% and 227.6%, respectively, as compared to CK. After two years continuous cropping of corn, the soil water loss in 120-200 cm soil layer in treatment PMF was up to 72 mm, being significantly higher than that in treatments SM (45 mm) and CK (40 mm). It was suggested that PMF could increase the soil temperature at seedling-tasselling stage, promote the corn growth in its early growth period, improve the soil water use by corn, and consequently, increase the grain number per spike and 100-grain weight, manifesting a good effect in improving corn yield and water use efficiency. However, PMF also induced more soil water consumption in 100-200 cm soil layer, which was not beneficial to the water balance through years.

[Effects of nitrogen fertilization on wheat leaf photosynthesis under elevated atmospheric CO2 concentration].

In this paper, the effects of nitrogen (N) fertilization on the wheat leaf photosynthesis under long-term elevated atmospheric CO2 concentration (760 micromol x mol(-1)) was studied, based on the measurements of photosynthetic gas exchange parameters and light intensity-photosynthetic rate response curves at jointing stage. Under the long-term elevated atmospheric CO2 concentration, applying sufficient N could increase the wheat leaf photosynthetic rate (Pn), transpiration rate (Tr), and instantaneous water use efficiency (WUEi). Comparing with those under ambient atmospheric CO2 concentration, the Po and WUEi under the elevated atmospheric CO2 concentration increased, while the stomatal conductance (Gs) and intercellular CO2 concentration (Ci) decreased. With the increase of light flux intensity, the Pn and WUEi under the elevated atmospheric CO2 concentration were higher those under ambient atmospheric CO2 concentration, Gs was in adverse, while Ci and Tr had less change. At high fertilization rate of N, the Gs was linearly positively correlated with Pn, Tr, and WUEi, and the Gs and Ci had no correlation with each other under the elevated atmospheric CO2 concentration but negatively correlated under ambient atmospheric CO2 concentration. At low fertilization rate of N, the Gs had no correlations with Pn and WUEi but linearly positively correlated with Ci and Tr. It was suggested that under the elevated atmospheric CO2 concentration, the wheat leaf Pn at low N fertilization rate was limited by non-stomatal factor.