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Land use influences soil biota community composition and diversity, and then belowground ecosystem processes and functions. To characterize the effect of land use on soil biota, soil nematode communities in crop land, forest land and fallow land were investigated in six regions of northern China. Generic richness, diversity, abundance and biomass of soil nematodes was the lowest in crop land. The richness and diversity of soil nematodes were 28.8 and 15.1% higher in fallow land than in crop land, respectively. No significant differences in soil nematode indices were found between forest land and fallow land, but their network keystone genera composition was different. Among the keystone genera, 50% of forest land genera were omnivores-predators and 36% of fallow land genera were bacterivores. The proportion of fungivores in forest land was 20.8% lower than in fallow land. The network complexity and the stability were lower in crop land than forest land and fallow land. Soil pH, NH4+-N and NO3−-N were the major factors influencing the soil nematode community in crop land while soil organic carbon and moisture were the major factors in forest land. Soil nematode communities in crop land influenced by artificial management practices were more dependent on the soil environment than communities in forest land and fallow land. Land use induced soil environment variation and altered network relationships by influencing trophic group proportions among keystone nematode genera.

Topographic factors are important potential determinants of soil nitrogen (N) availability as they influence temperature and moisture at the local scale, thereby affecting plant N use strategies. To date, the effects of slope aspect and position on N acquisition pattern for alpine species remain poorly understood. We conducted a field 15N labeling experiment (i.e.,15N-NO3−, 15N-NH4+or 15N-glycine) at three different aspects and altitudes to investigate effects of terrain changes on uptake of inorganic and organic N for two common plant species (Stipa purpureaand Saussurea japonica) in a semi-arid alpine steppe on the northern Tibetan Plateau. Plant N utilization strategies were largely controlled by changes in soil nutrients along the topographical gradients. The mean value of NO3−absorption rate was the highest among the three N forms for the two species (S. purpurea: 5.49 µg N g− 1dry mass; S. japonica: 4.73 µg N g− 1dry mass), but there were differences across various types of topography. At the lower sites, the two species showed a clear absorption preference for NH4+and glycine, as these two N forms were the highest among the three slope positions. S. purpureaand S. japonicaat the south-facing aspect had the highest NO3−absorption rate, which was well matched with the higher soil NO3−availability of the southern-facing aspect (1.65–3.19 mg kg− 1). Our study reveals that plant N utilization strategies are intricately linked to the variability of soil nutrients across different topographical gradients. These results underscore the critical role of physical topography in shaping N acquisition patterns in alpine ecosystems, offering valuable insights for anticipating how changes in climate may impact plant N uptake strategies in these environments.

The deposition of the extracellular matrix, especially collagen, and the elevated expression levels of reactive oxygen species, including H2O2, are the main features of fibrosis. Fibrosis can occur in many tissues, such as tumor and liver tissues. The deposition of collagen in the location of lesions not only leads to immunological rejection and supports liver fibrosis and tumor progression, but also provides unique physiological signals with the progression of fibrosis and tumor. However, at present, the detection of fibrosis, especially real time detection, is greatly difficult, making it important to develop noninvasive probes for the dynamic monitoring of fibrosis progression. Herein, we propose a H2O2responsive macromolecular probe for collagen imaging with high sensitivity and specificity. This probe consists of a collagen-targeting peptide and a H2O2-sensitive and near-infrared (NIR)-emitting macromolecular optical probe, which could effectively bind to collagen both in vitroand in vivoin the region of tumor or fibrotic liver tissues, allowing for high sensitivity and noninvasive visualization of fibrotic tissues and real time monitoring of collagen degradation after anti-fibrotic drug treatment.

The urine of yaks (Bos grunniens) and Tibetan sheep (Pantholops hodgsoni) represents a vital source of nutrients in the alpine grasslands on the Qinghai-Xizang Plateau, and its crucial role in affecting soil properties and greenhouse gas (GHG) emissions cannot be underestimated. However, few in-situ experiments examining the impacts of yak and Tibetan sheep urine deposition on the alpine grassland nutrient dynamics and GHG fluxes, and the underlying mechanisms and influential factors associated with GHG emissions in urine deposited grasslands are still not well understood. This study conducted a 33-day simulated urine deposition experiment that include the treatments of yak urine (YU), Tibetan sheep urine (TSU), and a control (CK) without any application in an alpine steppe of northern Xizang Plateau. We collected soil samples at depths of 0–10 cm, 10–20 cm, and 20–30 cm after 11, 21, 33 days of experimental treatments to explore its physicochemical and microbial properties. The GHG samples were collected respectively at 1, 3, 5, 8, 13, 18, 27, and 33 d of the experiment by using the method of artificial static closed chamber and determined the nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4) concentration by using a gas chromatograph. The gene abundance of 0–10 cm soil ammonia-oxidizing archaea (AOA), ammonia-oxidizing bacteria (AOB), membrane-bound nitrate reductase (NarG), nitrite reductase encoding gene (NirS), nitric oxide reductase gene (NorB), and nitrous oxide reductase encoding gene (NosZ) were determined using real-time fluorescence quantitative PCR. The results showed that cumulative N2O, CO2, and CH4emissions for YU treatment across the 33-day experimental period amounted to 49.6 g N ha− 1, 73.8 kg C ha− 1, and − 176 g C ha− 1, respectively, with the values significantly (P< 0.05) greater than the emissions for CK treatment (36.4 g N ha− 1, 23.5 kg C ha− 1, and − 232 g C ha− 1). The deposition of YU and TSU immediately increased soil nutrient availability, anaerobic conditions, and microbial activity, which led to increasing N2O, CO2, and CH4emissions to vary degrees, and reduced CH4uptake. Soil CO2flux for YU treatment exhibited a significant (P< 0.05) negative correlation with NO3−-N concentration, while soil CH4flux exhibited extremely significant (P< 0.01) negative correlation with SOC concentration. Soil N2O flux for TSU treatment was negatively correlated with soil NifH, AOB, AOA, and NirSgene abundances (P< 0.05). In contrast, the cumulative N2O, CO2, and CH4emissions during the initial 13 days for YU and TSU treatments accounted for a significantly (P< 0.05) higher proportion (49.9% and 46.6%, 66.1% and 64.9%, 40.2% and 49.0%, respectively) of the total emissions compared to the CK treatment (43.8%, 40.7%, and 31.0%). Urine application resulted in 0–10 cm soil AOA, AOB, NirS, NarG, and NosZ gene abundances for YU treatment were significantly (P< 0.05) higher than that for CK treatment. The significant enhancement of 0–10 cm soil functional gene abundance (NirS, NorB, and NosZ), as well as increased levels of NH4+-N and NO3−-N concentrations for YU and TSU treatments during the early stage of the experiment (P< 0.05), proving the strengthen of denitrification activity and soil respiration and therefore resulted in a higher proportion of N2O and CO2emissions. The conclusions would contribute to a better understanding of the short-term effects and functional mechanisms of urine deposition on alpine steppe GHG emissions, and provide scientific insights for optimising livestock urine management model and facilitating the greenhouse gas emission reduction strategies in pastoral areas.

For an aviation brushless synchronous starter/ generator system, rotors of the main exciter (ME) and main machine (MM) rotate synchronously. Meanwhile, abundant current harmonic in ME's rotor, which is caused by a rotating rectifier, contains rotor position information. Then, the rotor position of MM can be obtained indirectly by signals of ME. In this article, based on rotor current characteristics of the excitation system, the estimated rotor current of ME and MM is employed innovatively for rotor position estimation at low speed. First, the harmonic current characteristics in ME's rotor winding are analyzed, and the low-order harmonic can be used for rotor position increment estimation. However, the rotor current of ME cannot be measured directly. Fortunately, in dq coordinate, it can be estimated by the measurable signal in stator winding. Furthermore, by operations of rotation transformation and low-pass filtering, rotor position increment can be obtained. Meanwhile, by injecting low-frequency rotating signals into MM's stator, the initial rotor position of MM can be obtained by sampling the estimated main field current at a fixed point. Finally, by combining rotor position increment and initial rotor position, sensorless starting control can be realized. The proposed method can avoid the influence of MM's operating state and experiments verify the effectiveness.

Load frequency regulation (LFR) is regarded as a significant method for the stable operation of modern power grids. However, the LFR is facing many challenges such as communication delays in the area control error, and external disturbances caused by renewable energy integrating into power grids. This paper presents a cascaded improved active disturbance rejection control (ADRC) to handle these control challenges, where the inner and outer controllers are the improved ADRC and regular ADRC, respectively. The advantages of the improved ADRC to reject external disturbances and system uncurtains are discussed by simulations. Then a practical parameter tuning method is provided to guide the selection of controller parameters. Finally, comparative simulations are implemented to illustrate the abilities of the proposed control scheme in different cases. The proposed control structure can handle the communication delay well and have a strong ability to reject the disturbances of uncertain consumed power and wind power. The simulation results imply that the cascaded improved ADRC may have broad application prospects for the LFR.

Due to the reliability problems of mechanical position sensors, rotor position estimation technology is an alternative for the starting control of aircraft wound-field synchronous starters/generators. Reversible saliency and high-frequency attenuation characteristics of the main machine (MM) may lead to the failure of existing high-frequency signal-based estimation methods. In this article, low-frequency signal (LFS) injection and a novel signal extraction method are combined to estimate rotor position. First, LFS is injected into MM's stator winding, and a response signal containing rotor position information is induced in its rotor field winding. Then, the response signal can be extracted from the estimated main field current (EMFC) by a bandpass filter. Furthermore, the phase of the extracted signal and the injected LFS are obtained by two single-phase phase-locked loops (PLLs), respectively. Then, the increment in the rotor position can be obtained by the two PLLs. Meanwhile, by injecting a specific low-frequency square wave, the initial rotor position can also be extracted from EMFC, requiring no extra pole identification and phase compensation. Finally, by combining the initial rotor position and position increment, a continuous rotor position of MM can be obtained. The effectiveness of the proposed method is verified by experiments.

The ability of wheat to adapt to a wide range of environmental conditions is determined mostly by allelic diversity among genes regulating vernalization requirement. Vrn-1is a major regulator of this requirement. In this study, two novel alleles of Vrn-A1were discovered in Chinese cultivars: vrn-A1nwas identified in two landraces, Jiunong 2 and Ganchun 16, and Vrn-A1owas detected in Duanhongmangmai. Both novel alleles showed a linked duplication in the promoter region. The common copy of these two alleles was identical to the recessive allele vrn-A1. Compared with the recessive allele vrn-A1, the other copy of vrn-A1ncontained a 54-bp deletion in the promoter region and the distinct copy of Vrn-A1ocontained an 11-bp deletion in the promoter region. In segregating populations in the greenhouse under nonvernalizing (20–25 °C) and long-day (16 h light) conditions, plants with the novel vrn-A1nallele did not head earlier than those with the recessive vrn-A1allele. However, plants that were either homozygous or heterozygous for the novel Vrn-A1oallele headed earlier than those with the recessive vrn-A1allele. To identify the novel allele with the small-sized product and facilitate screening, a DNA marker for the novel dominant allele Vrn-A1owas designed. Analysis of the novel-allele distribution showed that two cultivars carrying the vrn-A1nallele were dispersed in the northwestern spring wheat zone, and 12 cultivars carrying the dominant Vrn-A1oallele were widely distributed in the northwestern spring wheat zone, Xinjiang winter and spring wheat zone, Yellow and Huai River valley winter wheat zone, and Qinghai-Tibetan Plateau spring and winter wheat zone. Our study identifies useful germplasm and a DNA marker for wheat breeding.

The high incidence of cancer has placed an enormous health and economic burden on countries around the world. In addition to evidence of epidemiological studies, conclusive evidence from animal experiments and mechanistic studies have also shown that morbidity and mortality of some cancers can be attributed to ambient fine particulate matter (PM2.5) exposure, especially in lung cancer. However, the underlying carcinogenetic mechanisms of PM2.5remain unclear. Furthermore, in terms of risks of other types of cancer, both epidemiological and mechanistic evidence are more limited and scattered, and the results are also inconsistent. In order to sort out the carcinogenic effect of PM2.5, this paper reviews the association of cancers with PM2.5based on epidemiological and biological evidence including genetic, epigenetic, and molecular mechanisms. The limitations of existing researches and the prospects for the future are also well clarified in this paper to provide insights for future studies.

During on-load starting process of an aviation wound-field synchronous starter/generator system, accurate rotor position information is required. Mechanical position sensor is susceptible to interference, increasing volume and weight, so online rotor position estimation is more desirable. Harmonics of main exciter (ME) caused by rotating rectifier are analyzed, and the fifth harmonic is used creatively to estimate rotor position in this article. In this method, by performing coordinate transformation on stator current of ME, rotor position increment is extracted and obtained through a low-pass filter. Meanwhile, taking advantage of the unidirectional conduction characteristics of rotating rectifier, a new idea to estimate initial rotor position is also proposed. In this approach, pulse signal is injected into the stator winding of main generator (MM) every fixed electrical angle, then the maximum and minimum current response correspond to that of MM's S and N pole respectively. Finally, combine initial rotor position and position increment, continuous rotor position of MM can be gained. The proposed methods avoid dependence on the saliency of MM, require no high-frequency signal injection and do not need secondary magnetic pole identification. Effectiveness and advantages of the proposed method are verified on the test.

A MOF-templated method was designed for controllable synthesis of oxygen-deficient LiCoMnO4materials for superior electrochemical performance as broad-voltage cathodes induced by the morphological feature and optimized atomic and electronic structure.

In recent years, the increasing demand for renewable energy and portable electronic devices has underscored the significance of developing high-performance, safe, and cost-effective energy storage systems. Potassium-ion batteries (PIBs) have emerged as a promising alternative to lithium-ion batteries (LIBs) owing to the abundance and cost-effectiveness of potassium, coupled with their favorable electrochemical performance. However, the widespread use of PIBs is limited by the lack of efficient and stable anode materials. Recently, zeolite imidazolate framework (ZIF) derivatives, characterized by high specific surface area and tunable pore size, have emerged as promising anode materials for PIBs owing to their exceptional electrochemical properties and structural stability. This article reviews the synthesis methods of ZIF derivatives and examines the potassium storage mechanisms involving intercalation, alloying, and conversion reactions within anodes. It also delves into the research advancements of ZIF derivatives, encompassing ZIF-derived carbon materials, alloying metals, metal selenides, metal sulfides, metal phosphides, and metal tellurides, explored as potential anode materials for PIBs. Finally, this review outlines the current challenges, future research outlooks, and prospective research avenues towards the commercialization of ZIF-based PIB anodes.

Compared with the impressive achievements of catalytic carbonyl–olefin metathesis (CCOM) mediated by Lewis acid catalysts, exploration of the CCOM through Brønsted acid-catalyzed approaches remains quite challenging. Herein, we disclose a synthetic protocol for the construction of a valuable polycycle scaffold through the CCOM with the inexpensive, nontoxic phosphomolybdic acid as a catalyst. The current annulations could realize carbonyl–olefin, carbonyl–alcohol, and acetal–alcohol in situ CCOM reactions and feature mild reaction conditions, simple manipulation, and scalability, making this strategy a promising alternative to the Lewis acid-catalyzed COM reaction.

A small molecular probe (Ir-fliq) and a macromolecular optical probe (Ir-fliq-PVP) based on an iridium complex are designed for hypoxia imaging and antibacterial chemotherapy in this work. The existence of both isoquinoline and fluorene moieties in the probe structure extends the phosphorescence emission to the red-wavelength region. The rigid large conjugated structure of the ligand can also reduce the packing caused by intermolecular interactions and suppress the self-quenching, thus improving the phosphorescence efficiency. The hydrophilic Ir-fliq-PVP has a good ability to generate singlet oxygen and can be used for photodynamic antimicrobial chemotherapy (PACT). Moreover, the small molecular probe Ir-fliq is further cross-linked with carboxymethyl chitosan (CMCS) and sodium alginate (SA) to form a CSGI hydrogel. The biocompatibility, mechanical properties, antibacterial properties and hypoxic imaging ability of the CSGI hydrogel have been evaluated in chronic wound models of diabetic mice. It shows that the CSGI hydrogel can effectively inhibit the growth of bacteria in wounds through PACT under light irradiation, promote the healing of chronic wounds in diabetic mice, and record the hypoxia process of mouse wounds.

Photocatalytic oxalic acid (OA) activation for pharmaceutical wastewater degradation based on Fe-based catalysts are usually limited by the cycle of Fe3+/Fe2+and low conversion efficiency of OA. Herein, an effective OA activator, FeOOH loaded FeWO4/WO3(FFW) heterojunction photocatalyst, were fabricated by electrostatic self-assembly for tetracycline (TC) degradation. Experimental results revealed that the introduction of FeOOH can greatly enhance the optical absorption and separation efficiency of photogenerated carriers of the FeWO4/WO3(FW) composite. Moreover, optimized FFW heterojunction exhibited the excellent photocatalytic OA activation activity and the highest OA conversion rate for TC degradation, which exhibited 97.3% photocatalytic performance for TC within 30 min under 420 nm light irradiation. The FFW heterojunction still revealed high photocatalytic OA activation activity for TC degradation even after six cycles. The possible degradation pathway of TC and photocatalytic OA activation mechanism of FFW heterojunction were also presented by ESR spectroscopy results, quenching tests, and LC-MS analysis. This work not only provides a fresh perspective on the surface photo-Fenton chemistry of catalytic redox processes, but also presents a valid reference for designing highly efficient photocatalytic OA-activation systems for pharmaceutical wastewater treatment.

Bioorthogonal chemistry together with biomarker-installing techniques is very promising in the amplification of the tumor targeting efficiency of nanomedicine. In this work, we newly synthesized an amphiphilic block copolymer polyoxazoline-block-polycaprolactone (POX-PCL) in which a certain number of amino groups were dangled in the side chain of the POX block and then functionalized into triarylphosphine groups for active tumor targeting via Staudinger ligation. By using the block copolymer self-assembly, the Staudinger ligation reagent-containing and drug-loaded reactive micelles were prepared with a hydrodynamic diameter of ∼74 nm. Such drug-loaded reactive POX-PCL micelles exhibited significant tumor target ability through the Staudinger ligation between the micelles and the tumors metabolically labeled with azide group, as demonstrated by a series of in vitro and in vivo evaluations. In this work, a novel method was proposed for the application of Staudinger ligation in the nanomedicine for amplifying the tumor targeting ability and antitumor activity of nanodrugs.

With continuous growth in scale, topology complexity, mission phases, and mission diversity, challenges have been placed for efficient capability evaluation of modern combat systems. Aiming at the problems of insufficient mission consideration and single evaluation dimension in the existing evaluation approaches, this study proposes a mission-oriented capability evaluation method for combat systems based on operation loop. Firstly, a combat network model is given that takes into account the capability properties of combat nodes. Then, based on the transition matrix between combat nodes, an efficient algorithm for operation loop identification is proposed based on the Breadth-First Search. Given the mission-capability satisfaction of nodes, the effectiveness evaluation indexes for operation loops and combat network are proposed, followed by node importance measure. Through a case study of the combat scenario involving space-based support against surface ships under different strategies, the effectiveness of the proposed method is verified. The results indicated that the ROI-priority attack method has a notable impact on reducing the overall efficiency of the network, whereas the O-L betweenness-priority attack is more effective in obstructing the successful execution of enemy attack missions.

The continuous increasing demand for egg quality and quantity, and the expanding market share have enabled the egg industry to achieve significant benefits through genetic improvement. This study aims to estimate the genetic parameters and explore selectable breeding traits in the purebred Rhode Island Red (RIR) and White Leghorn (WL), which are two high-yielding layer breeds, and better understand their underlying genetic basis and accelerate genetic progress. The DMU software was utilized to analyze 12 egg quality traits, including egg length (EL), egg width (EW), egg shape index (ESI), egg weight (EWT), albumen height (AH), yolk color (YC), Haugh unit (HU), yolk weight (YW), albumen weight (AW), albumen-to-egg weight ratio (AWR), yolk-to-albumen ratio (YAR), and yolk-to-egg weight ratio (YWR). In RIR, the heritability of egg quality traits ranged from 0.196 to 0.427, while the repeatability ranged from 0.395 to 0.668. In WL, the heritability of egg quality traits ranged from 0.203 to 0.347, and the repeatability ranged from 0.424 to 0.656. In both RIR and WL, highly strong genetic correlations were observed between AW and EW, as well as between AW and EWT. The genetic correlations for AW and EW were 0.902 in RIR and 0.864 in WL, while the genetic correlations for AW and EWT were 0.981 in RIR and 0.960 in WL. The egg quality traits in both breeds showed moderate heritability, indicating great genetic potential for improvement through selective breeding. This can help breeders meet the increasingly diverse egg preferences of consumers through genetic selection. Additionally, there is a highly strong correlation between egg width/egg weight, and albumen weight in both breeds. In practical production, it is feasible to estimate albumen weight by measuring egg width and egg weight, which can simplify the method for measuring albumen weight. In conclusions, our finding provided valuable insights into the genetic architecture of egg quality traits in RIR and WL chickens. They help our understanding of the potential for genetic improvement of these traits through selective breeding programs.

It is important for antitumor drugs to accumulate at the tumor site and penetrate deeply to play a role in treatment. However, it is difficult for the drugs to reach the destination on account of the complex tumor microenvironment such as elevated tumor interstitial fluid pressure (IFP) and solid stress. Here, we report a type of nanocarrier composed entirely of Camellia oleiferaprotein (COP), which could lower tumor IFP and solid stress. Its physicochemical properties, cellular uptake, in vitrocytotoxicity and tumor perfusion, biodistribution, and in vivoantitumor efficiency were evaluated. It was found that COP NPs had good cellular uptake ability and cytocompatibility. When loading doxorubicin, COP NPs showed an in vitroconcentration-dependent cytotoxicity. Importantly, the tumor IFP and solid stress were greatly reduced after injecting COP NPs into tumor-bearing mice, leading to more drug accumulating in the tumor and a longer survival time for tumor-bearing mice. Therefore, our study provided a new strategy to improve the tumor microenvironment and to achieve better antitumor efficiency.

To evaluate the effect of organic amendments on soil nematode community composition and diversity within aggregate fractions, a study was initiated in agricultural soils with four-year organic amendments. Soil samples were collected from the plow layer (0–20 cm) under three cornfield management scenarios: 1) conventional cropping (CK, corn straw removal and no organic manure application); 2) straw retention (SR, incorporation of chopped corn stalk); and 3) manure application (MA, chicken manure input). The soil samples were fractionated into four aggregate sizes, i.e., >2 mm (large macroaggregates), 1–2 mm (macroaggregates), 0.25–1 mm (small macroaggregates), and <0.25 mm (microaggregates, silt and clay fractions). The composition and diversity of soil nematode communities were determined within each aggregate fraction. The results showed that both SR and MA treatments significantly increased the percentage of macroaggregates (>1 mm) and only MA treatment strongly increased the mean weight diameter compared to the CK (P<0.05). The abundance of total nematodes and four trophic groups were affected significantly by the aggregate fractions and their higher abundance occurred in the larger aggregates. The effects of aggregate size on most nematode genera were significant. Bacterivores in the small macroaggregates and microaggregates, and fungivores in the large macroaggregates were significantly different among treatments. The percentage of bacterivores increased after the application of organic materials, while that of fungivores decreased. It can be concluded that organic management significantly affects soil aggregation and soil characteristics within aggregates, and the aggregate size subsequently influences the distribution of nematode communities.

For the better part of the 21st century, opioid abuse and related consequences have beleaguered the United States. Effectively fighting the crisis may require a better understanding of potential differences among the types of opioids available as treating them as one homogeneous group may mask emerging trends and conflate more benign ones with those more troubling. The purpose of our study is to investigate changes in prescribing patterns of four groups of opioids (hydrocodone, oxycodone, fentanyl, and other) and how community-level factors explain their variation over time. We use a census tract–level data set with population, concentrated disadvantage, and prescription drug monitoring payment variables to address our goals. Findings show disparate prescribing patterns among the four types of opioids and considerable differences in the community factors that predict their change. Implications for future research and interventions follow.

Abstract In functional data analysis (FDA), the covariance function is fundamental not only as a critical quantity for understanding elementary aspects of functional data but also as an indispensable ingredient for many advanced FDA methods. A new class of nonparametric covariance function estimators in terms of various spectral regularizations of an operator associated with a reproducing kernel Hilbert space is developed. Despite their nonparametric nature, the covariance estimators are automatically positive semi-definite, which is an essential property of covariance functions, via a one-step procedure. An unconventional representer theorem is established to provide a finite dimensional representation for this class of covariance estimators based on data, although the solutions are searched over infinite dimensional functional spaces. To further achieve a low-rank representation, another desirable property, e.g., for dimension reduction and easy interpretation, the trace-norm regularization is particularly studied, under which an efficient algorithm is developed based on the accelerated proximal gradient method. The outstanding practical performance of the trace-norm-regularized covariance estimator is demonstrated by a simulation study and the analysis of a traffic dataset. Under both fixed and random designs, an excellent rate of convergence is established for a broad class of operator-regularized covariance function estimators, which generalizes both the trace-norm-regularized covariance estimator and other popular alternatives. [ABSTRACT FROM AUTHOR]

Abstract This paper develops the asymptotic properties of a recently proposed measure of inequality emphasizing the status of the poor relative to the rich. A simulation confirms the asymptotic results are applicable in practice. [ABSTRACT FROM AUTHOR]

In the military arms race, the focus of the defender is on selecting the optimal development plan of armaments, i.e., advantageous defense resources allocation. As an indispensable feature of armaments, the cooperative interactions between different armaments influence their effectiveness directly, but they have not been elaborated yet in the existing study. In this regard, a mathematical formulation, named operation loop, is proposed to investigate the cooperative interactions between armaments, sequentially facilitating the description of the development plans’ performance. Additionally, the defender's development plans of armaments depend much on the attacker's weapons, bringing the characteristics of multiobjective into this problem. Furthermore, the uncertainty about the development plans of the attacker has been taken into consideration as well. Therefore, the paper concentrates on formulating the resources allocation problem with incomplete information as a network design problem. By optimizing the network design using covariance matrix adaptation evolution strategy, an effective armaments development plan can be obtained. The feasibility is demonstrated by a case study.

This review discusses recent studies on dendrimer- based nanoparticles in cancer chemotherapy and gene therapy. In order to achieve the high efficacy and low side effects of chemotherapy and gene therapy, it is essential to combine the unique features of dendrimers and the specific tumor microenvironment to target delivery and control release of therapeutic agents to tumor tissues and cells. Strategies to design the dendrimer-based delivery system in this review include non-modified dendrimers, dendrimer conjugates, assembled amphiphilic dendrimers, nanohybrid dendrimer carriers and dendrimers with inherent activity. In addition, specific functional groups on these dendrimers as stimuli-responsive system for targeting delivery and controlled release of therapeutic agents are discussed. 针对肿瘤组织的微环境, 结合树状大分子的特点可以构建定向可控药物、基因传递系统, 实现化学或基因治疗中的高效低毒. 本综 述从树状大分子的结构出发, 总结了其纳米载体在肿瘤治疗中的最新进展, 尤其重点讨论了传统树状大分子、树状大分子偶联物、可自 组装的两亲性树状大分子、杂化树状大分子及自身具有药理活性的树状大分子作为药物或基因递送载体的应用. 我们希望本综述将有助 于启发未来的相关研究, 以进一步拓展这种材料在肿瘤治疗中的新应用.

Rechargeable Zn-air batteries (ZABs) constitute promising next-energy conversion and storage systems due to their low cost, intrinsic safety, and feasibility to fabricate high energy density and stable charge and discharge voltage. Nevertheless, the most significant challenge of rechargeable ZABs is relatively high over potential owing to the sluggish kinetics of oxygen reactions on the air cathode, requiring high-performance noble-metal-free bifunctional electrocatalysts with highly cost-effective. Herein, we developed a facile and scalable coprecipitation strategy to successfully prepare CuO/Co3O4@CNTs catalysts for bifunctional oxygen electrocatalysts. This unique strategy enables CuO/Co3O4nanoparticles to be uniformly grown on CNTs and the simultaneous pyrolysis process results in the generation of ultrafine CuO/Co3O4heterostructures. Contributed to an abundance of heterostructures, the oxygen vacancies and unsaturated chemical bonds in the interface were generated in CuO/Co3O4. Consequently, the CuO/Co3O4@CNTs delivered bifunctional activity of ΔE of 0.78 V and good stability that can maintain 1000 h charge and discharge cycles.

We propose optimal weighting schemes for both mean and covariance estimations for functional data based on local linear smoothing such that the L 2 rate of convergence is minimized. These schemes can self-adjust to the sampling plan and lead to practical improvements. [ABSTRACT FROM AUTHOR]

Near‐isogenic lines (NILs) of three Chinese winter wheat varieties were used to explore quality differences between subunits 5 + 10 and 2 + 12. Protein content, gluten quality, rheological properties, and bread‐making quality in the NILs possessing subunits 5 + 10 and 2 + 12 were assessed and compared. All measured parameters except protein content significantly changed when subunits 2 + 12 were replaced by subunits 5 + 10. The incorporation of subunits 5 + 10, in the absence of subunits 2 + 12, increased dramatically dough strength, but the extensibility was slightly decreased. The improved functionality of subunits 5 + 10 was only pronounced in the recipient cultivar (Xiaoyan 22) which had weak gluten strength but better extensibility, whereas, the inferior overall quality was obtained in the recipient cultivars (Xinong 2208 and Xinong 1718) carrying medium‐to‐strong gluten strength and poor extensibility. The functionality of subunits 5 + 10 was well expressed in the recipient cultivars with weak gluten strength and better extensibility. The findings expanded our knowledge on the functionality of subunits 5 + 10 on different genetic backgrounds with gradient elasticity‐to‐extensibility ratio. The transformed lines with extremely strong gluten strength and reduced extensibility could be used as parents in wheat quality breeding and their flour would be suitable for blending with flour of the lower grade.

A class of new dendritic phospholipid compounds with different hydrophilic dendritic poly(l-lysine) peripheries from generations 1 (G1) to 3 (G3) (DPL-1 to DPL-3) were synthesised and nano-drug delivery systems based on these compounds were prepared (DPN-2 and DPN-3). DPL-1 couldn't self-assemble into nanocarriers. The size, TEM image, and the CD spectrum of DPN-2 and DPN-3 were experimentally examined. The effect of the peripheral structure of dendritic phospholipid-based nanocarriers on their biological performance and drug delivery efficiency was studied. In vitrocytotoxicity studies demonstrated that the DOX-loaded DPN-3 shows higher cytotoxicity against 4T1 cells and BGC823 cells than DPN-2. DOX-loaded DPN-3 also showed excellent behaviours in cell internalization and 4T1 multicellular spheroid penetration. The composition of the hydrophilic block in dendritic phospholipids affected the self-assembly behaviour, properties and delivery efficiency of the formed nanocarriers. This work will be helpful for building drug delivery systems with characteristics of high delivery efficiency and low cytotoxicity for clinical applications.

Natural wetlands are permanently or seasonally inundated with water, and the growth of vegetation in these wetlands is assumed to be sensitive to a warming climate. China's natural wetlands are mostly found in cold, high‐latitude (>40°N in NE China) and high‐altitude (>4,000 m in average on the Tibetan Plateau (TP)) areas. Rapid warming of regional climate (>0.30°C decade−1since the 1960s) is thought to have promoted the growth of vegetation in these cold wetlands. However, using three independent greenness data sets, we show that the wetlands in the TP and NE China experienced significant browning between 1999 and 2007, rather than a straightforward increase in greening. The interannual variation in wetland greenness on the TP was regulated by both the temperature and the amount of solar radiation. In NE China, however, the effect of temperature and solar radiation was unable to explain the temporal variation in greenness and the changes were mostly regulated by the soil moisture content and drought. There was a decrease in the dependence of vegetation growth on temperature in NE China, but no significant change on the TP, which has experienced a warmer and wetter climate in recent decades. The effect of drought and the soil moisture content on the interannual variation in the greenness of wetlands consistently increased across the TP and NE China. Our results highlight the hydrological regulation of the growth of vegetation in a warmer climate, even in wetland environments. China's natural wetlands have experienced significant warming of 0.49°C decade−1China's natural wetlands experienced significant browning from 1999 to 2007The effect of drought and soil moisture content on the interannual variation in the greenness of wetlands increased

The objective of this study was to explore the geological origin of glauconite, which is believed to precipitate and mature very slowly (~1 Myr) in neritic environments (shallow water, oceanic coastal zones, at water depths of 100–200 m) with very low sedimentation rates. A series of simulation experiments was designed and carried out in sealed tubes placed in an oven and heated to a constant temperature of 50°C (±2°C) for 60 or 150 d. The parent materials used for these experiments were two low-Fe montmorillonites with different crystallinities. The montmorillonites were introduced to solutions with concentrations of 0.02–0.1 mol/L Fe3+and 0.05–0.2 mol/L K+with various values of pH and Eh. The products were analyzed using X-ray powder diffraction (XRD), Fourier-transform infrared (FTIR) spectrometry, electron spin resonance (ESR) spectrometry, scanning electron microscopy (SEM), and Mössbauer spectroscopy. The morphological changes from parent material to product were observed under SEM, which revealed the formation of a flaky mineral (e.g. a product formed in the interstitial spaces between montmorillonite crystals). The formation of a flaky mineral indicates that the product is a layer silicate. Qualitative analysis of XRD patterns revealed that the main product phase was a mica group mineral and the d060value was consistent with the presence of glauconite (0.152 nm) and/or Fe-illite (0.150 nm). A glauconite and Fe-illite mineral assemblage formed in a weakly acidic solution, while Fe-illite, mixed-layer Fe-illite, and montmorillonite formed in neutral and alkaline solutions. Stretching vibrations of Fe(III)Fe(III)OH-AlFe(II)OH and/or MgFe(III)OH were observed in FTIR spectra (3550–3562 cm−1) of the products formed in acidic solutions, which along with the g = 1.978 ESR signal indicated that Fe(III) entered octahedral positions in the tetrahedral/octahedral/tetrahedral layer (TOT) platelets. The AlFe(II)OH-MgFe(III)OH (3550–3562 cm−1) and AlFe(III)OH (870 cm−1) vibrations were only observed in products formed in neutral and alkaline solutions. Analysis of the Mössbauer spectra showed that Fe(III) substituted for Al and Mg in the cisoctahedral sites of montmorillonite. The simulation experiments demonstrated that the pH and redox conditions (Eh) of the environment controlled the nature of the product mineral species. Results of the present study revealed that glauconitization and illitization occurred under different conditions, where glauconitization preferentially occurred in an acidic environment and illitization preferentially occurred in a nearly neutral to alkaline environment.

MOFs derived Co2VO4/Co with big BET surface area and excellent rate performance was prepared for highly efficient lithium-ion batteries and sodium-ion batteries

Combat modeling is an important area of military operations. System of system counterwork is an important mode of information-based war which is a mode of “network centered” instead of “platform centered” and “capability oriented” instead of “function oriented”. Under the conditions of informationization, the combat model must therefore address these challenges by properly representing the networked efficient based on mutual relations among combat entities. The implementation process of combat system of systems capability is analyzed which is the result of complex interactions between the entities in four domains through a sequence of action processes. The combat network model of combat system of systems is described which reflects the fundamental structure of combat system of systems. The entity with three types of functions and five types of relations in the combat network is analyzed. The capability loop is defined and the evaluation index of combat network of combat system of systems is proposed based on the capability loop analysis. Finally, an example is used to illustrate the methodology.

Zu Ketten angeordnetund mit einem hoch vernetzten Polymer überzogen wurden kolloidale Fe3O4‐Nanokristallcluster mit ungefähr 200 nm Durchmesser in einer Eintopfsynthese. Die Nanoketten zeigen erhöhte Wasserstoff‐Relaxationszeiten T2, lassen sich leicht in Wasser dispergieren und mit einem Magnet manipulieren und sind sehr gut bioverträglich.

Fluorescent single‐wall carbon nanotubes (SWCNTs) were prepared by mixing cut SWCNTs with acridine orange (AO). The optical absorbance and fluorescence characteristics of AO–SWCNT conjugates display interesting pH‐dependent properties. Fluorescence microscopy in combination with transmission electron microscopy proves that AO–SWCNTs can enter HeLa cells and are located inside lysosomes. The endocytosis‐inhibiting tests show that the clathrin‐mediated endocytosis is a key step in the internalization process. The internalized AO–SWCNTs remain inside lysosomes for more than a week and have little effect on cell proliferation. These findings may be useful in understanding the SWCNT‐based intracellular drug delivery mechanism and help to develop new intracellular drug transporters.

Natural polysaccharides such as amylose (AMY), alginate sodium (ALG), and chitosan (CHI) have been noncovalently wrapped onto single-wall carbon nanotubes (SWCNTs) to give a series of SWCNT scaffolds, termed as AMY-SWCNT, ALG-SWCNT, CHI-SWCNT, and CHI/ALG-SWCNT scaffolds. Compared to purified SWCNTs and oxidized SWCNTs, the polysaccharide-wrapped SWCNTs can well mimic nanofibrous extracellular matrix and significantly enhance cell adhesion and proliferation. The surface properties of the SWCNT scaffolds, such as functional groups, surface charge, and hydrophilicity, can all directly influence the protein adsorption and lead to changes in cellular FAK expression, thus affect the mammalian cell morphology and proliferation. By quantitatively studying the surface properties of these SWCNT scaffolds, it can be concluded that relatively positively charged hydrophilic scaffolds that bear −OH groups can remarkably promote cell growth. Considering all properties, the relatively electrical neutral and hydrophilic AMY-SWCNT scaffolds bearing only −OH groups are able to sustain the highest cell viability after 72 h culturing.

Functional data analysis, which handles data arising from curves, surfaces, volumes, manifolds and beyond in a variety of scientific fields, is a rapidly developing area in modern statistics and data science in the recent decades. The effect of a functional variable on an outcome is an essential theme in functional data analysis, but a majority of related studies are restricted to correlational effects rather than causal effects. As the first attempt in the literature, the causal effect is studied for a functional variable as a treatment in cross-sectional observational studies. Despite the lack of a probability density function for the functional treatment, the propensity score is properly defined in terms of its top functional principal component scores which can represent the functional treatment approximately. Two covariate balancing methods are proposed to estimate the propensity score, which minimize the correlation between the treatment and covariates. The appealing performance of the proposed method in both covariate balance and causal effect estimation is demonstrated by a simulation study. The proposed method is applied to study the causal effect of body shape on human visceral adipose tissue. [ABSTRACT FROM AUTHOR]

The key to developing novel applications of SWNTs in biotechnology and biomedicine is to improve their biocompatibility and solubility in water and to assemble them into useful architectures. We describe how amylose can help to solubilize SWNTs and wrap around SWNTs into helical superstructures with periodic pitch. FT‐IR, Raman spectroscopy, 1H NMR and HR‐TEM are used to confirm the generation of amylose/SWNTs complexes (A/S‐C). It is demonstrated that most of the A/S‐C have similar diameters (ca. 20–30 nm) and a helical morphology with a pitch of ca. 14 nm. A test of Hela cell viability revealed that the A/S‐C had much better biocompatibility than SWNTs.

The work reported here resolves, at the level of gene regulation, the controversy as to whether or not human monocytes/macrophages can produce nitric oxide (NO) when stimulated with lipopolysaccharide (LPS), with or without co‐stimulation by interferon‐γ(IFN‐γ). Studies included structural comparison of the promoters for human and mouse inducible NO synthase (iNOS) genes, transfection and assay of human and mouse iNOS promoter regions in response to LPS ± IFN‐γ, and electrophoretic mobility shift assays of KB response elements. Two explanations for hyporesponsiveness of the human iNOS promoter to LPS ± IFN‐γ were found: (1) multiple inactivating nucleotide substitutions in the human counterpart of the enhancer element that has been shown to regulate LPS/IFN‐γ‐induced expression of the mouse iNOS gene; and (2) an absence of one or more nuclear factors in human macrophages (e.g., an LPS‐inducible nuclear factor‐κB/Rel complex), that is (are) required for maximal expression of the gene. The importance of resolution of this controversy is that future research in this area should be directed toward the understanding of alternative mechanisms that can result in the successful production of NO.

Lipopolysaccharide (LPS) is one of the most potent stimuli for macrophages. The activities of LPS have been attributed to the lipid A region of the molecule. We have previously shown that pretreatment of macrophages with very low doses of LPS can selectively “reprogram” these cells to respond differentially to subsequent activation, as assessed by tumor necrosis factor‐α and nitric oxide (NO) production. Here we demonstrate that the relative capacity of various LPS preparations for induction of down‐regulation of subsequent LPS‐activated NO production correlates well with their relative potency for initiation of NO formation. Although LPS‐dependent activation can be regulated by a pertussis toxin (PT)‐sen‐ sitive factor, the LPS pretreatment‐induced reprogramming is shown here to be refractory to regulation by PT. These results suggest that, although the structural components of LPS dictating the relative activities of the molecule for activation versus reprogramming are similar, there may exist different pathways in initiation of LPS‐induced activation versus reprogramming.

Covalent organic frameworks (COFs) have received much attention in the biomedical area. However, little has been reported about stimuli-responsive COF for drug delivery. Herein, we synthesized a hypoxia-responsive azo bond-containing COF with nanoscale size and immobilized both photosensitizers chlorin e6 (Ce6) and hypoxia-activated drug tirapazamine (TPZ) into the COFs. When such a COF entered the hypoxic environment and tumor, the COF structure was ruptured and loaded drugs were released from the COF. Together, upon near-infrared (NIR) light irradiation, Ce6 consumed oxygen to produce cytotoxic reactive oxygen species, leading to elevated hypoxia. Such two-step hypoxia stimuli successively induced the deintegration of COF, drug release and activation of TPZ. This promoted the TPZ to generate massive biotoxic oxyradical. In vitro and in vivo evaluation indicated that this two-step hypoxia-activated COF drug delivery system could kill cancer cells and inhibit the growth of tumors effectively.

The varying-coefficient additive model is a novel tool for analyzing functional data. The model generalizes both the varying-coefficient model and the additive model, and retains their merits as an effective dimension reduction model that is flexible yet easily interpretable. However, the original method only works for densely recorded functional response processes with time-invariant covariates. To broaden its applicability, the model is extended to allow for time-dependent covariates and a new fitting approach is proposed that can handle sparsely recorded functional response processes. Consistency and L 2 rate of convergence are developed for the proposed estimators of the unknown functions. A simple algorithm is developed that overcomes the computational difficulty caused by the non-convexity of the objective function. The proposed approach is illustrated through a simulation study and a real data application. [ABSTRACT FROM AUTHOR]