Effect of N fertilization rate on soil alkalihydrolyzable N, subtending leaf N concentration,fiber yield, and quality of cotton

Soil alkali-hydrolyzable nitrogen, which is sensitive to N fertilization rate, is one of the indicators of soil nitrogen supplying capacity. Two field experiments were conducted in Dongtai(120°19″ E, 32°52″ N), Jiangsu, China in 2009 and Dafeng(120°28″ E, 33°12″ N), Jiangsu province, China in 2010. Six nitrogen rates(0, 150, 300, 375, 450, and 600 kg ha^(-1)) were used to study the effect of N fertilization rate on soil alkali-hydrolyzable nitrogen content(SAHNC), subtending leaf nitrogen concentration(SLNC), yield, and fiber quality. In both Dongtai and Dafeng experiment station, the highest yield(1709 kg ha^(-1)), best quality(fiber length 30.6 mm, fiber strength 31.6 c N tex^(-1), micronaire 4.82), and highest N agronomic efficiency(2.03 kg kg^(-1)) were achieved at the nitrogen fertilization rate of 375 kg ha^(-1). The dynamics of SAHNC and SLNC could be simulated with a cubic and an exponential function,respectively. The changes in SAHNC were consistent with the changes in SLNC. Optimal average rate(0.276 mg day^(-1)) and duration(51.8 days) of SAHNC rapid decline were similar to the values obtained at the nitrogen rate of 375 kg ha^(-1)at which cotton showed highest fiber yield, quality, and N agronomic efficiency. Thus, the levels and strategies of nitrogen fertilization can affect SAHNC dynamics. The N fertilization rate that optimizes soil alkali-hydrolyzable nitrogen content would optimize the subtending leaf nitrogen concentration and thereby increase the yield and quality of the cotton fiber.

Ameliorative effects of potassium on drought-induced decreases in fiber length of cotton(Gossypium hirsutum L.) are associated with osmolyte dynamics during fiber development

Fiber length of cotton(Gossypium hirsutum L.)decreases under drought stress,potassium(K)could diminish the decreased caused by drought,but the mechanism associated with this alleviation effect is not clear.We evaluated the effect of K on fiber elongation using two cotton cultivars,Simian 3 and Siza 3,grown in well-watered and drought-stressed conditions.Potassium fertilizer(K2O)was applied 0,150,or 300 kg ha?1 in each growing condition.Drought stress reduced the final fiber length due to a decline in the maximum rate of rapid elongation(Vmax,mmday?1).The application of K alleviated the droughtinduced fiber length reduction by increasing Vmax.At 10 and 15 days post-anthesis(DPA),drought significantly reduced osmotic potential(OP)and increased K+and malate contents at all K rates,relative to well-watered conditions,which was associated with increased activities of phosphoenolpyruvate carboxylase(PEPC),V-ATPase,PPase,and PM H+-ATPase in cotton fiber.However,the relative contribution of K+and malate to OP declined under drought in comparison with well-watered condition.Compared with control without K,K application decreased OP and increased the accumulation of osmolytes(K+,malate and soluble sugar)as well as the activities of related enzymes in fiber irrespective of water treatments.Moreover,K application increased osmotic adjustment during drought,and improved the contribution of K+and malate to OP,especially under drought stress.This study showed that drought decreased fiber length by reducing Vmax,and K application ameliorates the decline in fiber elongation due to drought by enhancing osmolytes accumulation and their contribution to OP in fiber cells.

Implementation method of Oil and Gas Geologic Information System with ArcGIS Engine

ComGIS is the mainstream of developing GIS currently.Developing Geographic Information System with the technology of components can reduce the difficulties of developing,improving the developing efficiency and enhancing the flexibility and opening of system.ArcObjects(AO) is based on the technology of COM,and ArcGIS Engine(AE) is a set of embedded AO which can extend to various platforms.Compared with AO,ArcGIS Engine can shorten the period of developing and improve the efficiency greatly.Having introduced the techniques of ArcObjects and ArcGIS Engine,we offer the method of developing GIS with Visual Basic and ArcGIS Engine with Oil and Gas Geologic Information System.

Individual and interactive influences of elevated air temperature and soil drought at the flowering and boll-forming stage on cottonseed yield and nutritional quality

As the main byproduct of cotton production,cottonseed yields edible vegetable oil,ruminant feed,and industrial products.We evaluated the individual and interactive effects of elevated air temperature and soil drought on cottonseed yield and nutritional quality using two cotton cultivars,Sumian 15(heat-susceptible)and PHY370 WR(heat-tolerant).The experiment was conducted under three levels of soil relative water content(SRWC):(75±5)%,(60±5)%and(45±5)%and two temperature regimes:ambient temperature(AT,31.0/26.4℃,mean daytime/night temperature)and elevated temperature(ET,33.4/28.9℃).Cottonseed yield,boll number,seed number,and single-seed weight were lower under combined ET and SRWC(45±5)%than either individual stress or combined stresses in comparison with the control treatment(SRWC(75±5)%under AT).Drought tended to increase oil content and reduce protein content,whereas ET showed almost the opposite effects.Under the combination of ET and soil drought,oil content was still higher than under control,although ET weakened the beneficial effects of drought.For protein,ET offset the negative impacts of mild drought on protein content,but protein content was not increased under SRWC(45±5)%.Each stress or combined stress reduced oil and protein yields under all treatments,owing to declines in cottonseed yields.The combined stress reduced unsaturated fatty acid(UFA)/saturated fatty acid(SFA)and essential amino acid(EAA)/non-essential amino acid(NAA).Compared with PHY370 WR,the sensitivity of Sumian 15 to the combined factors was evidenced in the following ways:(1)seed yield,yield components,oil and protein yields were decreased more for Sumian 15 than PHY370 WR compared with the control treatment;(2)the combined stresses caused lower oil content,UFA,and UFA/SFA in Sumian 15 than PHY370 WR;(3)interaction effects of the combined factors on protein content and EAA/NAA were detected only in Sumian 15.

An improved master-apprentice evolutionary algorithm for minimum independent dominating set problem

The minimum independent dominance set(MIDS)problem is an important version of the dominating set with some other applications.In this work,we present an improved master-apprentice evolutionary algorithm for solving the MIDS problem based on a path-breaking strategy called MAE-PB.The proposed MAE-PB algorithm combines a construction function for the initial solution generation and candidate solution restarting.It is a multiple neighborhood-based local search algorithm that improves the quality of the solution using a path-breaking strategy for solution recombination based on master and apprentice solutions and a perturbation strategy for disturbing the solution when the algorithm cannot improve the solution quality within a certain number of steps.We show the competitiveness of the MAE-PB algorithm by presenting the computational results on classical benchmarks from the literature and a suite of massive graphs from real-world applications.The results show that the MAE-PB algorithm achieves high performance.In particular,for the classical benchmarks,the MAE-PB algorithm obtains the best-known results for seven instances,whereas for several massive graphs,it improves the best-known results for 62 instances.We investigate the proposed key ingredients to determine their impact on the performance of the proposed algorithm.

T_1-T_2双模式磁共振造影剂的设计及应用

核磁共振成像作为一种无侵入的早期诊断方式早已在临床上得到了非常广泛的应用,其成像方式分为弛豫加权和扩散加权,其中弛豫加权又分为T_1加权成像和T_2加权成像。为了增强MR图像对比度,可通过引入造影剂,根据其增强类型可以分为阳性的T_1造影剂和阴性的T_2造影剂。虽然两种造影剂各有其优点,但是也存在着一些不足,因此一种全新的T_1-T_2双模态造影剂应运而生。T_1-T_2双模态造影剂的优势就在于可以利用同一台仪器,实现MRI成像在时间和空间上的精确匹配。本文系统地总结了T_1-T_2双模态造影剂的设计思路和其化学合成方法,并对其生物医学应用作了介绍。

Wearable energy harvesters generating electricity from low-frequency human limb movement

A wearable energy harvester technology is developed for generating electricity from the movement of human joints.A micro-electroplated ferromagnetic nickel cantilever is integrated with a piezoelectric element and bonded on a flexible substrate.Based on the magnetic interaction between the magnetized cantilever and a magnet on the substrate,a novel vertical-vibration frequency-up-conversion(FUC)structure is formed to generate stable amounts of electric energy per cycle from the horizontal substrate stretching/rebounding.The two ends of the flexible substrate are attached on both sides of a limb joint to transform joint rotation into substrate stretching.During limb movement,the flexible substrate is horizontally stretched and rebounded,causing the cantilever to vertically release from and return to the magnet,thereby exciting the piezoelectric cantilever into resonant generation.Since the horizontal lowfrequency limb movement is perpendicular to the vertical high-frequency resonance,the stretch has little influence on the resonance of the cantilever.Thus the generated energy is always stable within a wide frequency range of limb movements.The performance of the novel harvester is experimentally verified using a stretching/rebounding movement cycle,where the cycle corresponds to the frequency range of 0.5–5.0 Hz.Within one stretching/rebounding movement cycle,the generated electric energy is stable in the approximate range of 0.56–0.69μJ for the whole frequency range.Two flexible harvesters are worn on the human elbow and knee for a body kinetic energy harvesting test.Considerable power can always be generated under typical low-frequency limb movements,such as squatting,walking,jogging,and fast running,where the peak-to-peak generated voltages are always approximately 4.0 V.Additionally,energy harvesting under two-directional area stretching is also realized by adjusting the FUC structure layout.The flexible-substrate harvester is promising for various wearable applications.

Cytotoxicity of mitochondrial-targeting silica-coated manganese oxide nanoparticles

The mitochondrion is a promising target for diagnosis and therapy. Mitochondrial-targeting silica-coated manganese oxide nanoparticles(Mn O@Si O2-PPh3+ NPs) were successfully synthesized to explore the mitochondrial cytotoxicity of nanoparticles. The mitochondrial targeting property was confirmed by a laser scanning confocal microscopy experiment. Even after incubation for only 4 h, the cytotoxicity of Mn O@Si O2-PPh3+ NPs against cancer cells was obvious; the ATP content was significantly decreased to 40%; and the mitochondrial membrane potential was depleted. All of these results indicated the collapse of mitochondrial function and the start of a cell apoptosis pathway. Our findings suggest that mitochondrial-mediated apoptosis could be strengthened by targeting to the subcellular compartment.

Correlation between clinical course and radiographic development on CT scan in patients with COVID-19

Background:To analyze the correlation between clinical course and radiographic development on computed tomography(CT)in patients with confirmed coronavirus disease 2019(COVID-19)and to provide more evidence for treatment.Methods:This retrospective,observational,cohort study enrolled 49 patients with Reverse transcription-polymerase chain reaction(RT-PCR)-confirmed COVID-19,which included 30 patients admitted to the intensive care unit(ICU)of Wuhan Third Hospital and 19 patients either admitted to or receiving telemedicine consultation from Shanghai General Hospital,Shanghai Xuhui Dahua Hospital,and hospitals in other provinces.CT scans were performed in all enrolled patients and the radiographic features including simple ground-glass opacities(GGOs),GGO with interlobular septal thickening,consolidations with GGO,and consolidations only were monitored by repeating the CT.The progression of these radiographic features was analyzed in combination with their clinical staging and the time interval between onset of symptoms to CT.Results:Based on illness severity,the 49 patients were classified into four stages:mild(n=6),moderate(n=12),severe(n=16),and critically ill(n=15).The CT findings were classified into three phases:early(n=5),progres-sion(n=39),and recovery(n=5).Among the 49 patients,9 had bilateral diffuse GGO or diffuse consolidations(white lungs)and were counted as 18 lesions.Three patients had no abnormal findings on initial CT,but their repeat CT showed new lesions.In all,we identified 892 lesions including simple GGO,GGO with interlobular septal thickening,consolidations with GGO,and consolidations only.Conclusions:Most patients had pulmonary lesions on the posterior,inferior,and peripheral lung fields on CT.The development of GGO with interlobular septal thickening,GGO with consolidations,and consolidations only happened mainly between day 8 and 14.The emergence of consolidations may suggest the progression to the severe phase of the illness,whereas simple consolidations or“white lung”may suggest a critically ill phase.