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China is planning to launch a relay satellite in the coming years with a payload for the Earth–Moon very-long-baseline interferometer observation research and scientific applications, known as the lunar orbit very-long-baseline interferometry (VLBI) experiment (LOVEX) system. This system will perform the LOVEXs for in the world, and will improve the accuracy of planetary spacecraft orbit determination and the scientific observation capabilities of astrophysics and astrometry. Prior to launch, key technologies of the system must be verified, so we have established a LOVEX ground validation system with similar performance to the LOVEX system. The LOVEX ground validation system consists of a 4.5-m ring-focus antenna, $X$ -band receiver, frequency converter and digital backend, hydrogen maser, and monitoring and control software. Using this system, we have successfully conducted VLBI differential observation experiments with the Shanghai 65 m radio telescope and Beijing 50 m radio telescope. The experimental results show that, after calibration with NRAO150, the standard deviations (STDs) of delay error of Tianwen-1 are within 0.5 ns, consistent with the theoretical timing accuracy, verifying the feasibility of the LOVEX time-delay calibration.

Improving both grain yield and resource use efficiencies simultaneously is a major challenge in rice production. However, few studies have focused on integrating dense planting with delayed and reduced nitrogen application to enhance grain yield, nitrogen use efficiency (NUE) and radiation use efficiency (RUE) in rice (Oryza sativaL.) in the double rice cropping system in South China. A high-yielding indicahybrid rice cultivar (Yliangyou 143) was grown in field experiments in Guangxi, South China, with three cultivation managements: farmers’ practice (FP), dense planting with equal N input and delayed N application (DPEN) and dense planting with reduced N input and delayed N application (DPRN). The grain yields of DPRN reached 10.6 and 9.78 t ha–1in the early and late cropping seasons, respectively, which were significantly higher than the corresponding yields of FP by 23.9–29.9%. The grain yields in DPEN and DPRN were comparable. NUE in DPRN reached 65.2–72.9 kg kg–1, which was 61.2–74.1% higher than that in FP and 24.6–30.2% higher than that in DPEN. RUE in DPRN achieved 1.60–1.80 g MJ–1, which was 28.6–37.9% higher than that in FP. The productive tiller percentage in DPRN was 7.9–36.2% higher than that in DPEN. Increases in crop growth rate, leaf area duration, N uptake from panicle initiation to heading and enhancement of the apparent transformation ratio of dry weight from stems and leaf sheaths to panicles all contributed to higher grain yield and higher resource use efficiencies in DPRN. Correlation analysis revealed that the agronomic and physiological traits mentioned above were significantly and positively correlated with grain yield. Comparison trials carried out in Guangdong in 2018 and 2019 also showed that DPRN performed better than DPEN. We conclude that DPRN is a feasible approach for simultaneously increasing grain yield, NUE and RUE in the double rice cropping system in South China.

Through C–O–Mn bonding, graphene nanosheets are homogeneously dispersed in porous Mn3O4to take full advantages of porous Mn3O4and graphene nanosheets, making the as-formed three-dimensional porous Mn3O4/reduced graphene oxide (rGO) composite exhibit good electrochemical performance. Besides, C–O–Mn bonding is demonstrated to greatly promote the Faradic reactions of the composite, resulting in the enhancement of its real capacity in supercapacitor (SC) electrodes as well as lithium-ion battery (LIB) anodes. By simply fine-tuning the content of graphene (<7 wt %), the composite with 2.8 wt % of rGO delivers a high capacitance of 315 F g–1at 0.5 A g–1with a high rate capability of 64.7% at 30 A g–1and an excellent cycling stability of 105% (5 A g–1, 5000 cycles) as an SC electrode. Also, the one with 6.9 wt % rGO can present a reversible capacity of more than 1500 mAh g–1at 0.05 A g–1as the LIB anode, the highest value reported to date, which remains 561 mAh g–1at 1 A g–1.

The environmental fates of cadmium (Cd) in the soil and groundwater systems largely depend on its adsorption isotherms and kinetic with the soil matrix. Combined with HYDRUS–1D software, batch and column studies were conducted in this study to investigate the adsorption and movement process of Cd in soil and groundwater systems. The results from static adsorption experiment indicated that the second order model and Langmuir model could provide the better description for adsorption behavior of Cd. The results from SEM –EDS and XPS analysis revealed that the main adsorption mechanism of Cd were ion exchange, complexation and precipitation. The results from Tessier's sequential extraction suggested that more Cd would be diffused to the deeper soils, since the higher percentage of Cd were found in the exchangeable fractions. The results from soil column experiments and numerical analyses demonstrated that standard convection–dispersion equation (CDE) could better describe Cd breakthrough curve (BTCs) of column adsorption than the other three solute transport models within HYDRUS–1D software. Noteworthy, the horizontal and vertical migration distance of Cd (II) reached about 8 m after 50,000 days and 10 m after 15,000 days, respectively, indicating the easily mobile Cd (II) might be eventually released from contaminated soils to groundwater. Based on the above results, this study not only provided a new insight into the migration mechanism of Cd in the soil and groundwater environment, but was also beneficial to formulating remediation strategies of contaminated sites.

The cavity-based X-ray free-electron laser (XFEL) has promise in producing fully coherent pulses with a bandwidth of a few meV and very stable intensity, whereas the currently existing self-amplified spontaneous emission (SASE) XFEL is capable of generating ultra-short pulses with chaotic spectra. In general, a cavity-based XFEL can provide a spectral brightness three orders of magnitude higher than that of the SASE mode, thereby opening a new door for cutting-edge scientific research. With the development of superconducting MHz repetition-rate XFEL facilities such as FLASH, European-XFEL, LCLS-II, and SHINE, practical cavity-based XFEL operations are becoming increasingly achievable. In this study, megahertz cavity enhanced X-ray generation (MING) is proposed based on China’s first hard XFEL facility - SHINE, which we refer to as MING@SHINE.

In View of the Multi-View Face Detection Problem under Complex Background, an Improved Face Detection Method Based on Multi-Features Boosting Collaborative Learning Algorithm Integrating Local Binary Pattern (LBP) is Presented. Firstly, Facial Skin Color Information is Used to Exclude most of the Background Regions. then, Haar-like Feature and LBP Feature are Extracted from Facial Candidate Regions and Inputted into a Modified Adaboost Algorithm to Obtain a Strong Classifier. Lastly, in Order to Improve the Detection Speed, Pyramid Classifier System Structure is Adopted to Determine the Face. the Experimental Results on CMU Standard Test Set and Life Photos, the Proposed Method has Achieved the Rapid Detection of Multi-View Face Image.

The β-cyclodextrin modified graphene sheets exhibit enhanced thermal stability and dispersibility. β-Cyclodextrin functionalized graphene could strengthen the performance of composites based on PVA.

H1N1 was a new and potentially serious infectious disease, in human, the severity of influenza can vary from mild to severe, thus to find an effective and safety way to control the influenza pandemic is of crucial importance. This retrospective study describes the duration of viral shedding in H1N1 patients that were hospitalized and treated in China.

A new permeable reactive composite electrode (PRCE) attached with a permeable reactive layer (PRL) of Fe0 and zeolite has been developed for soil pH control and the improved removal efficiency of heavy metal ions (Cd, Ni, Pb, Cu) from soil in electrokinetic remediation process. The effects of different composite electrodes on pH control and heavy metal removal efficiency were studied, and changes in the forms of heavy metals moved onto the electrodes were analyzed. The results showed that with acidic/alkaline zeolite added and renewed in time, the composite electrodes could effectively neutralize and capture H+ and OH- produced from electrolysis of the anolyte and catholyte, avoiding or delaying the formation of acidic/alkaline front in tested soil, preventing premature precipitation of heavy metal ions and over-acidification of soil, and thus significantly improved the heavy metal removal efficiency. Fe0 in composite electrodes could deoxidize and stabilize the heavy metal ions. After that capture and immobilization of the pollutants were achieved. The results also showed that, using "Fe0 + zeolite" PRCE in the cathode with timely renewal, after 15-day remediation with a DC voltage of 1.5 V/cm, the total removal rates of Cd, Pb, Cu and Ni were 49.4%, 47.1%, 36.7% and 39.2%, respectively.

A simple means was demonstrated to control the functional group on surface and use this surface as a model support to investigate the effect of surface chemistry on lipase adsorption and its activity. It was based on mixing polystyrene (PS) solution with small molecular weight functional group-terminated polystyrenes (PS-Fs, functional groups such as-CH3, -CF3, -NH2, -COOH and-OH) and casting them on glass plates to fabricate the functional group controlled surfaces. The amount of adsorbed lipase on the surface with similar functional group density was-CH3 > PS > -CF3 > -NH2 > -COOH > -OH. The activity retention of the immobilized lipase was-OH > -NH2 > -COOH > -CF3 > -CH3 > PS.

A classical crystallization process starts from stable nuclei followed by a simple enlargement of the nuclei by unit-cell replication. In recent years, the universality of such classical crystallization has been questioned upon investigations of biomineralization processes, and there are few examples showing that crystal growth may not follow such a classical crystallization process. In this paper, a typical coordination polymer, Prussian blue microcrystals, has been synthesized under hydrothermal conditions. By carefully analyzing the intermediates during the crystal growth process, we found that the growth of Prussian blue under the given growth conditions may follow a nonclassical crystal growth process in which a mesoscale self-assembly of nanocrystallites is included during crystal growth. Such a mesoscale self-assembly process could be a common phenomenon for growth of some crystals with extremely low solubility.

ABSTRACTBloom syndrome (BS) is a rare human autosomal recessive disorder characterized by marked genetic instability associated with greatly increased predisposition to a wide range of cancers affecting the general population. BS arises through mutations in both copies of the BLM gene which encodes a 3’-5’ DNA helicase identified as a member of the RecQ family. Several studies support a major role for BLM in the cellular response to DNA damage and stalled replication forks. However, the specific function(s) of BLM remain(s) unclear. The BLM protein is strongly expressed and phosphorylated during mitosis, but very little information is available about the origin and the significance of this phosphorylation. We show here that ATM kinase provides only a limited contribution to the mitotic phosphorylation of BLM. We also demonstrate that BLM is directly phosphorylated at multiple sites in vitro by the mitotic cdc2 kinase, and identify two new sites of mitotic BLM phosphorylation: Ser-714 and Thr-766. Our results identify BLM helicase as a new substrate for cdc2, which may have potential physiological implications for the role of BLM in mitosis.

Objective: To evaluate the effects of treatment of integrative Chinese and Western medicine (ICWM) on arterial oxygen saturation (SaO2) in patients with severe acute respiratory syndrome (SARS).Methods:The non-randomized, controlled trial was conducted on 447 SARS patients treated synchronously with western conventional treatment (WM group,n= 171) alone and ICWM (ICWM group,n= 276). The changes of the cases with normal level (≥95%) or abnormal level (<95%) SaO2were observed dynamically.Results: In the 3rd-14th day of the therapeutic course, the percentage of patients with normal SaO2 in the ICWM group was higher than that in the WM group (OR = 0. 5178,P= 0.0038), and this tendency was more evident in patients of the severe type (OR = 0.18,P= 0.0001). However, the statistical significance of difference was only shown in patients for whom the ICWM treatment started in the early period after the onset (<-7 days after it, OR = 0.3803,P= 0.006), but not shown in those who received ICWM treatment later in the mid-late period of SARS (P>0.05).Conclusion: ICWM treatment, particularly when it is used for intervention in the early stage, is beneficial for maintaining normal SaO2in SARS patients.

Objective: To improve the effects of treatment of severe acute respiratory syndrome (SARS) and to explore the clinical significance of integrated traditional Chinese medicine and western medicine (ICWM) in the treatment of SARS and its influence on the chief indexes in the process of the disease.Methods: The clinical study involving observation of 135 patients of SARS was conducted in the randomized, synchronously controlled and open way. The patients were divided into two groups, 68 in the ICWM group and 67 in the control group, all of whom were treated with the same basic treatment of western medicine, but to the ICWM group, Chinese drugs for clearing Heat, detoxifying and removing Dampness were given additionally. The comprehensive effect on relieving fever, cell-mediated immunity, pulmonary inflammation and secondary infection was compared between the two groups.Results: The therapeutic effect in the ICWM group was better than that in the control group in such aspects as steadily lowering body temperature, alleviating general symptoms, accelerating the absorption of pulmonary infiltration and easing cellular immunity suppression.Conclusion: The therapeutic effect of ICWM is better in treating SARS than that of western medicine alone.

This study aimed to evaluate the effectiveness and feasibility of functional movement screen (FMS) evaluation system and individualized intervention measures in preventing military training injuries. A total of 420 recruits from a unit of the People's Liberation Army of China were included as the research object. According to random grouping method, they were divided into observation group (Group A) and control group (Group B), with 210 patients in each group. Before recruit training, individual FMS was performed, and functional correction training was performed in the observation group according to the test scores, while no intervention measures were applied in the control group. After 3 months of training, the tests were repeated. Age, body mass index (BMI), and incidence of military training injuries were recorded during the training period. There was no statistical difference between the two groups in age, BMI, FMS score before the training (P> .05). After receiving functional correction training, the FMS score of the Group A was higher than that of the Group B, and the difference was statistically significant (P< .05). The incidence of military training injury in Group A and Group B was 20.95% and 44.02%, respectively (P< .05), and the difference was statistically significant. The evaluation system of FMS and individualized intervention measures are feasible and effective in predicting and reducing the occurrence of military training injuries.

•Particle-size controlled porous nanoflowers forming hierarchical porous spongy-like MnO2with high specific surface area of >300 m2g−1are prepared in high yields at room temperature by a template-free way.•The formation as well as particle size of porous nanoflowers are determined by the nucleation concentration in the initial reaction.•The specific capacitance of mesoporous MnO2with similar crystallizations and morphologies is proved to be determined by its specific surface area.•Assembled MnO2//AC capacitor delivers a high specific energy of 12.5 Wh kg−1at 9 KW kg−1with a cycling stability of 96% after 2000 cycles at 5 A g−1.

A simple method for preparing Ag/Pd nanorings is reported. Energy dispersive X-ray element mapping results showed a random distribution of Ag and Pd atoms over the nanoring, indicating that the nanorings were made of an alloy of Ag and Pd. These nanorings were then successfully used as catalysts in electroless copper deposition. Results of quartz crystal microbalance measurements revealed that the catalytic activity of prepared Ag/Pd nanorings was better than that of monometallic Ag and Pd nanoparticles.

This article reports that triangular Ag∕Pdnanoshells are synthesized via the galvanic displacement reaction and further applied as activators for electroless copper deposition. Information as revealed by electrochemical quartz crystal microbalance, deposition rate catalyzed by the triangular Ag∕Pdnanoshells is ∼0.42μg∕cm2sand exhibit different electrochemical activity in the electroless deposition of copper.