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Guava (Psidium guajava L.) is a tropical fruit with great economic value. Guangdong is one of the most important guava production areas. In November 2019, guava wilt disease (GWD) was observed in a 10.6 HA commercial orchard in NanSha district, Guangzhou, Guangdong (22°37'37.626" N, 113°35'56.089" E). Disease incidence was up to 35%. Initially, leaves on the top of some branches became purple or yellow interveinal chlorosis, later dry. Infection severely became systemic developing vascular discoloration of stem, black root rot, eventually entire trees wilted and died. The root tissues were cut into 5-mm2 pieces and surface disinfected with 70% ethanol for 30 sec, 3 % sodium hypochlorite for 4 min, rinsed by the sterile water, then plated onto potato dextrose agar and incubated for 5 days at 25°C. A total of 8 monoconidial isolates with identical colony morphology were obtained. All formed cottony, whitish to pale yellow colonies. Conidiophores were dimorphic, penicillate and acremonium-like. Penicillate conidiophores gave rise to ovoidal, one-celled conidia (4.15 to 6.55×2.28 to 4.61 μm) (n=100) with truncated ends. Cylindrical or fusiform conidia (7.02 to 15.57×2.01 to 5.30 μm) (n=100) arose in long chains on acremonium-like conidiophores. Morphological characteristics of the isolates were consistent with those of Nalanthamala psidii (syn. Myxosporium psidii) reported by Schroers (2005). The rDNA internal transcribed spacer (ITS) and partial nuclear large-subunit ribosomal DNA (LSU) of two representative isolates (GDNS02 and GDNS08) were amplified using the primers pairs ITS4/ITS5 (White et al. 1990) and V9G/LR5 (de Hoog and Gerrits van den. 1998), respectively. The obtained sequences were deposited in GenBank under the accession nos. OM278372 to 73 (ITS) and OM278377 to 78 (LSU). BLASTn analysis showed 99.81% and 100% identities with the reported sequences of N. psidii CBS 116952 (AY864836) and CBS 110507 (AY554243). Maximum likelihood analyses of combined ITS and LSU sequences indicated that these two isolates being clustered with N. psidii strains. Pathogenicity tests were performed twice using healthy seedlings (60-70 cm height, cv. pearl). Each stem of five seedlings was wounded using a 5-mm sterile cork borer, and 5-day-old mycelium plugs of isolate GDNS08 were inoculated into the holes (25-cm above the soil line) and covered with Parafilm, sterile PDA plugs were placed into the wounds of additional 5 control seedlings. All plants were kept in a greenhouse (25℃, 80% relative humidity, 16/8-h day/night). After 3 months, all inoculated plants developed purple leaf, defoliation and wilt symptoms resembling those observed in the orchards, while the controls remained asymptomatic. Nalanthamala psidii was reisolated from the roots tissue of the inoculated plants, identity was confirmed by morphological characteristics and ITS sequence analyses as described above, but not from the controls, fulfilling Koch's postulates. Nalanthamala psidii has been previously reported as the causal agent of guava wilt in Taiwan, Philippines, South Africa and Bangladesh (Hsieh et al. 1976; Opina 1995; Schoeman et al. 1997; Alam et al. 2019). To our knowledge, this is the first report of N. psidii causing guava wilt in Guangdong, China. The outbreak of GWD in South Africa in the 1980s resulted in devastating losses to guava industry (Schoeman et al. 1997). Further research is needed to develop the integrated management to constrain this disease from spreading.

Guava (Psidium guajava L.) is a tropical fruit with great economic value. Guangdong is one of the most important guava production areas. In November 2019, guava wilt disease (GWD) was observed in a 10.6 HA commercial orchard in NanSha district, Guangzhou, Guangdong (22°37'37.626" N, 113°35'56.089" E). Disease incidence was up to 35%. Initially, leaves on the top of some branches became purple or yellow interveinal chlorosis, later dry. Infection severely became systemic developing vascular discoloration of stem, black root rot, eventually entire trees wilted and died. The root tissues were cut into 5-mm2 pieces and surface disinfected with 70% ethanol for 30 sec, 3 % sodium hypochlorite for 4 min, rinsed by the sterile water, then plated onto potato dextrose agar and incubated for 5 days at 25°C. A total of 8 monoconidial isolates with identical colony morphology were obtained. All formed cottony, whitish to pale yellow colonies. Conidiophores were dimorphic, penicillate and acremonium-like. Penicillate conidiophores gave rise to ovoidal, one-celled conidia (4.15 to 6.55×2.28 to 4.61 μm) (n=100) with truncated ends. Cylindrical or fusiform conidia (7.02 to 15.57×2.01 to 5.30 μm) (n=100) arose in long chains on acremonium-like conidiophores. Morphological characteristics of the isolates were consistent with those of Nalanthamala psidii (syn. Myxosporium psidii) reported by Schroers (2005). The rDNA internal transcribed spacer (ITS) and partial nuclear large-subunit ribosomal DNA (LSU) of two representative isolates (GDNS02 and GDNS08) were amplified using the primers pairs ITS4/ITS5 (White et al. 1990) and V9G/LR5 (de Hoog and Gerrits van den. 1998), respectively. The obtained sequences were deposited in GenBank under the accession nos. OM278372 to 73 (ITS) and OM278377 to 78 (LSU). BLASTn analysis showed 99.81% and 100% identities with the reported sequences of N. psidii CBS 116952 (AY864836) and CBS 110507 (AY554243). Maximum likelihood analyses of combined ITS and LSU sequences indicated that these two isolates being clustered with N. psidii strains. Pathogenicity tests were performed twice using healthy seedlings (60-70 cm height, cv. pearl). Each stem of five seedlings was wounded using a 5-mm sterile cork borer, and 5-day-old mycelium plugs of isolate GDNS08 were inoculated into the holes (25-cm above the soil line) and covered with Parafilm, sterile PDA plugs were placed into the wounds of additional 5 control seedlings. All plants were kept in a greenhouse (25℃, 80% relative humidity, 16/8-h day/night). After 3 months, all inoculated plants developed purple leaf, defoliation and wilt symptoms resembling those observed in the orchards, while the controls remained asymptomatic. Nalanthamala psidii was reisolated from the roots tissue of the inoculated plants, identity was confirmed by morphological characteristics and ITS sequence analyses as described above, but not from the controls, fulfilling Koch’s postulates. Nalanthamala psidii has been previously reported as the causal agent of guava wilt in Taiwan, Philippines, South Africa and Bangladesh (Hsieh et al. 1976; Opina 1995; Schoeman et al. 1997; Alam et al. 2019). To our knowledge, this is the first report of N. psidii causing guava wilt in Guangdong, China. The outbreak of GWD in South Africa in the 1980s resulted in devastating losses to guava industry (Schoeman et al. 1997). Further research is needed to develop the integrated management to constrain this disease from spreading.

Density functional theory calculations were used to study the effects of inherent impurities C, N, and O on the stability and the self-trapping of interstitial He atoms in body-centered-cubic vanad...

Long non-coding RNAs (lncRNAs) are important to the occurrence and advancement of human cancers. We found through GEPIA that LINC00893 was lowly expressed in thyroid carcinoma (THCA) tissues, whereas the specific functions of LINC00893 has never been reported in PTC. In the current study, we confirmed that LINC00893 was expressed at a low level in PTC cells. Through gain-of-function assays, we determined that LINC00893 overexpression abrogated proliferation and migration abilities of PTC cells. Through signal transduction reporter array we found that LINC00893 potentially modulated the signals of phosphatase and tensin homolog (PTEN)/AKT pathway. In addition, overexpression of LINC00893 increased the expression of PTEN but reduced the levels of phosphorylated AKT in PTC. Additionally, mechanism assays unveiled that LINC00893 stabilized PTEN mRNA via recruiting Fused in sarcoma (FUS) protein. Finally, rescue assays demonstrated that LINC00893 hampered the proliferation and migration of PTC cells via PTEN/AKT pathway. Together, our study first clarified that LINC00893 functions as a tumor suppressor in PTC by blocking AKT pathway through PTEN upregulation.

Vanadium alloys are the promising first wall and blanket materials for fusion reactors. Large amounts of helium (He) and hydrogen (H) impurities are produced inside the materials along with irradiation defects under neutron irradiation, leading to bubble formation and microstructure changes, which will degrade the thermal and mechanical properties of vanadium alloys. The microstructure changes of materials are influenced by the interactions of point defects with solute atoms. Nowadays, first-principles calculations are intensively performed to elucidate these interactions, clustering, and dissolution, which can provide valuable information for the design of high-performance anti-irradiation materials. This paper reviews the recent findings of the interactions of point defects (vacancies, self-interstitial atoms) with substitutional solutes and interstitial solutes (C, O, N, H, and He) as well as their clusters in vanadium and its alloys from first-principles calculations.

In this study, nanostructures were fabricated on sintered copper powders through alloying-dealloying method for investigating and analyzing drop penetration and wetting characteristics. Based on the high-speed video imaging, the kinetics of droplets immersing process were studied for multi-scale composite compact (MCC), featured with the microns for copper particle sizes and nanometers for the surface structures. The comparisons of various sizes of copper powders and different initial falling heights were conducted to explore the effect of porous structures. The results indicated that the nanostructures, with pore size and ligament size of approximately 30 nm and 50 nm respectively, could effectively enhance the hydrophilic performance for the sintered copper compacts. Moreover, larger powder size could lead to faster penetration, while the higher initial falling height facilitated the increase of the maximum spreading diameter of droplet, resulting in lower penetration time.

Chlorophyll a (Chl a), particulate organic carbon (POC) and biogenic silica (BSi) were determined in coastal waters adjacent to the Zhujiang (Pearl) River Estuary (ZRE) during summer, in order to examine the C:Chl a ratio of phytoplankton and phytoplankton carbon in the plume-impacted coastal waters during summer, as well as to assess the relative contribution of diatoms to the phytoplankton biomass, by the regression between Chl a, POC and BSi. Our results showed that the C:Chl a ratio (g/g) of phytoplankton was high (up to 142), likely due to high light intensity and nutrient limitation. The river plume input stimulated phytoplankton growth, especially diatoms, resulting in higher relative contribution of phytoplankton carbon (55%) and diatoms (34%) to POC in the plume-impacted region than those (33% and 13%) in high salinity area, respectively. Phytoplankton carbon (up to 538 μg/L) in the plume-impacted region was much higher than that (

With the development of portable and wearable devices, flexible displays have attracted extensive interest and have become increasingly important in our daily life. In this study, a flexible electrowetting display (FEWD) was proposed and fabricated. To prevent a short circuit between the top and bottom electrodes, various types of support pillars were fabricated on the top substrates through a photolithography technique. The FEWD was measured under positive and negative bending conditions, with the applied voltage increasing from 0 to 24 V. The aperture ratio and response time were investigated to better evaluate and understand the performance of the FEWD. The mechanical properties of the support pillars and the FEWD were evaluated by means of compression force and cyclic bending tests, respectively. The results showed that the FEWD operated properly at 24 V under a bending curvature of 0.25 cm−1, achieving the largest aperture ratio of 54.96%. Moreover, the oil movement could be influenced by the support pillars in the pixel. With the advantages of both optical performance and flexibility, an FEWD with support pillars is a novel item for future development of reflective transparent displays and provides a promising strategy for developing flexible, wearable, and visible devices.

This paper reports the distribution of natural radionuclides of 224, 223Ra in the surface water and stratified waters of the Luzon Strait and its adjacent waters during the cruises of September 2015 and May 2016. To understand the impact of the Fukushima nuclear accident, the artificial radionuclide 137Cs in the waters was also analyzed. The results showed that the activities of 224, 223Ra and 137Cs were all within the natural radioactive background levels of the marine environment in the South China Sea. 224Ra had a higher activity level in the water of the north South China Sea to the west of the Luzon Strait, and a lower activity level in the oceanic Philippine Sea to the east. The 137Cs activity had no obvious spatial trends. Based on the vertical trends of 224Ra, 137Cs, and water temperature and salinity at three stations (LS3, LS5 and LS8), the distinct characteristics of the activity levels and gradients of 224Ra and 137Cs among the tropical surface water, subsurface water and mid-deep water were revealed. Typhoon Rainbow event reversed the overall circulation of the Luzon Strait and its adjacent area. A huge amount of western Pacific water characterized by low 224Ra activities flooded into the South China Sea, reducing the activity level of 224Ra in the waters. However, there were no significant differences of 137Cs activity between the West Pacific and the north South China Sea, and ocean current changes had no effect on the 137Cs activity levels of the water bodies.

With the rising development of the portable and wearable sensors and displays, the compact power source devices have become increasingly important and indispensable in our daily life. In this study, a flexible triboelectric nanogenerator (TENG), fabricated by the direct ink writing (DIW) method, has been proposed for the purpose of vibration energy harvesting to support power for these electronic devices. To strengthen the effective contact area of the opposite triboelectric polarities, the silicone elastomer, as viscoelastic inks, is extruded out directly onto the aluminum foil through the nozzle tip to construct the triboelectric patterns with rich and regular micro structures on the surface. Various film thickness, printing fibers spaces, contact frequencies, applied forces and printing paths are investigated to better understand the effects of the printing parameters in detail. The results show that the TENG can yield an output voltage of 124 V and the corresponding maximum power density of 608.5 mW/m2. Meanwhile, via vibration energy harvesting, the TENG is demonstrated to sustainably drive 51 LEDs and a 3-in. electrowetting display. Our work paves a new way for the individual design and digital manufacture of friction surface structures for the flexible, stretchable and wearable TENG.

A series of dilution experiments were conducted along an environmental gradient in coastal waters during April to September 2016, in order to examine the regulation of protist grazing on bacterioplankton by physical processes. Our results suggested that the density gradient in the frontal zone and the pycnocline played a significant role in regulating protist grazing on bacterioplankton in marine environments. The highest bacterial growth rate (1.33 d−1) and grazing rate (1.05 d−1) occurred in the frontal zone along the inshore-offshore transect and in the deep chlorophyll maximum (DCM) that always matched with the pycnocline in terms of the vertical profile in offshore waters. Spatial variability in bacterial growth rate and grazing rate was related to the presence of the density gradient in the front and the DCM. The density gradient aggregated phytoplankton and bacterial cells, enhancing their biomass. Meanwhile, high phytoplankton biomass provided more labile organic carbon to bacterioplankton in the front and the DCM, improving bacterial growth. Hence, the density gradient improved bacterial abundance, consequently enhancing the efficiency of protist grazing. Our findings implied that the density gradient improved bacterial carbon converted to high trophic levels and altered carbon flow in microbial food web in marine environments.

Background and aims: Long non-coding RNA (lncRNA) FOXD2 adjacent opposite strand RNA 1 (FOXD2-AS1) is aberrantly expressed in various cancers and associated with cancer progression. A comprehensive meta-analysis was performed based on published literature and data in the Gene Expression Omnibus database, and then the Cancer Genome Atlas (TCGA) dataset was used to assess the clinicopathological and prognostic value of FOXD2-AS1 in cancer patients. Methods: Gene Expression Omnibus databases of microarray data and published articles were used for meta-analysis, and TCGA dataset was also explored using the GEPIA analysis program. Hazard ratios (HRs) and pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the role of FOXD2-AS1 in cancers. Results: This meta-analysis included 21 studies with 2391 patients and 25 GEO datasets with 3311 patients. The pooled HRs suggested that highly expressed FOXD2-AS1 expression was correlated with poor overall survival (OS) and disease-free survival (DFS). Similar results were obtained by analysis of TCGA data for 9502 patients. The pooled results also indicated that FOXD2-AS1 expression was associated with bigger tumor size and advanced TNM stage, but was not related to age, gender, differentiation and lymph node metastasis. Conclusion: The present study demonstrated that FOXD2-AS1 is closely related to tumor size and TNM stage. Additionally, increased FOXD2-AS1 was a risk factor of OS and DFS in cancer patients, suggesting FOXD2-AS1 may be a potential biomarker in human cancers.

Background and aims Prostate cancer-associated non-coding RNA transcript-1(PCAT-1), which is a newly discovered long non-coding RNA, is up-regulated in various cancers. We conducted a meta-analysis to assess the clinicopathological and prognostic value of PCAT-1 in patients with malignant tumors. Methods A systematic literature search involved PubMed, Medline, Cochrane Library, Web of Science, EMBASE database, Ovid, Chinese CNKI, and the Chinese WanFang database. The role of PCAT-1 in cancers was evaluated by pooled odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CIs). Results A total of 1005 patients from nine studies were included in this meta-analysis. High expression of PCAT-1 was associated with depth of infiltration, lymph node metastasis, distant metastasis and TNM stage. However, increased PCAT-1 expression was not related to gender, tumor size and differentiation. Moreover, high PCAT-1 expression was associated with poor overall survival (OS) and disease-free survival (DFS), and the pooled results suggested that PCAT-1 expression can be an independent predictive factor for overall survival. Conclusion This meta-analysis provides evidence that PCAT-1 expression is closely correlated with depth of infiltration, lymph node metastasis, distant metastasis and TNM stage, and that increased PCAT-1 expression may be a potential prognostic biomarker in human cancers. However, more large-scale studies are warranted.

Bacterial production is one of the key parameters to evaluate bacterial role in ocean carbon fluxes. Estimation of bacterial production requires the leucine-to-carbon conversion factors that change widely across environments. However, empirical leucine-to-carbon conversion factors (eCFs) are seldom determined in situ because of time consuming and little is known on regulating factors for the eCFs. During May 2015 to January 2016, fourteen dilution experiments were conducted, from the Zhujiang (Pearl River) Estuary to the coast of the northern South China Sea, to determine spatiotemporal variability in the eCFs and its potential controlling factors along an environmental gradient. The eCFs showed clear spatial variations with the highest (1.27–1.69 (kg C)/(mol Leu)) in low salinity waters (salinity 25). Substrate availability was responsible for spatial variability in the eCFs. In the pristine coastal waters, low eCFs was related to substrate limitation and leucine incorporated was respired to maximize the survival rather than bacterial production. Hence, the eCFs measurement was needed for estimating bacterial production accurately in various marine environments.

In this paper, a modeling framework by combining system dynamic (SD) model and optimal allocation model was developed to study water resources vulnerability and optimal water use structure, and the framework was applied in the middle reaches of Heihe River basin, northwest of China. The SD model could describe the dynamical change of water resources vulnerability by integrating water resources with socio-economic effect. The sensitivity analysis of SD model was then conducted to design appropriate scenarios for finding out the optimal development pattern, and based on which, an integrated water-saving scenario with lower water resources vulnerability was identified for optimization modeling. Then, an inexact fuzzy-parameter two-stage programming (IFTSP) model was developed and applied to optimize water use structure among industries under uncertainties. This study addresses the water resources vulnerability analysis in considering both water resources system and socio-economic system. Water resources vulnerability analysis was combined with optimization model to make adaptive water resources management plans. And the optimal allocation schemes under lower water resources vulnerability are more advantageous for regional sustainable development.

With the rapid growth of wearable and portable electronics, triboelectric nanogenerator (TENG) has shown great potential to dramatically improve our daily life as self-powered sensors in energy harvesting and human motion monitoring. In this study, we propose a multi-scale metal mesh electrode (MME) based TENG in low-processing cost with superior output performance and durability. MME is fabricated via controllable, convenient and cost-effective alloying-dealloying method to enhance the high specific contacting surface as positive electrode. Owing to the synergistic effect of micro and nanostructures on MME, the output performance of TENG can be increased evidently. Various fabrication processes, including electroplating time, corrosive time and corrosive solution, are investigated to rich the surface nanostructures and better explore the effect of manufacturing parameters. The results show that MME based TENGs generate the maximum output voltage of 175.77 V at a frequency of 4 Hz and vertical force of 15 N in compressing-releasing operations, which is 4 times larger than that of copper film electrode, while the corresponding power density is about 0.85 W/m2. To demonstrate the practical application, TENG can be integrated in breathing valve mask as respiratory monitoring sensor to detect real-time respiratory rate, respiration intensity within different breath conditions, and realize breath identification during sound production. Overall, this work expands the design and fabrication strategy for TENG positive electrode and opens a potential application for self-powered wearable electronics in human healthcare monitoring and multifunctional intelligent sensors.

Chaojie Liang,* Yongping Zhang,* Yu Zhang, Ruihuan Li, Zhimin Wang, Zhigang Wei, Jiansheng GuoDepartment of General Surgery, First Hospital/First Clinical College of Shanxi Medical University, Taiyuan, Shanxi 030001, People’s Republic of China*These authors contributed equally to this workBackground and aims: This study aimed to clarify the prognostic role of LINC01296 in various cancers, and to evaluate its effect on proliferation, metastasis, and the cell cycle in hepatocellular carcinoma (HCC) by data mining, bioinformatics, and in vitro validation.Methods: The prognostic role of LINC01296 in cancer patients was assessed by searching the PubMed, Embase, Web of Science, and Gene Expression Omnibus databases and calculating pooled hazard ratios (HRs) with 95% confidence intervals (CIs); this prognostic role was also evaluated using The Cancer Genome Atlas (TCGA). We detected LINC01296 expression in HCC cell lines, and lentivirus-mediated small interfering RNAs were used to silence LINC01296 in MHCC97H and Hep3B cells to explore the role of LINC01296 in cell proliferation, metastasis, and cell cycle progression with in vitro validation and bioinformatics.Results: The results indicated that LINC01296 overexpression was associated with poor overall survival (OS) and disease-free survival (DFS) in various cancers; however, LINC01296 expression was not associated with recurrence-free survival (RFS). Similar results were found with TCGA, which showed that LINC01296 expression was associated with the pathologic stage, tumor size, and differentiation in Asian cancer patients. Additionally, bioinformatics analysis revealed expression of 394 related genes, which indicated that LINC01296 could be involved in the tumorigenesis and progression of HCC. In vitro gene silencing experiments indicated that LINC01296 downregulation repressed cell proliferation, cell cycle progression, and the metastatic potential of HCC through the regulation of BUB1, CCNA2, and CDK1 expression.Conclusion: This study demonstrated that LINC01296 expression is related to poor OS and DFS in a variety of cancer types and that LINC01296 has an oncogenic role in HCC.Keywords: LINC01296, lncRNA, cancers, HCC, bioinformatics

Density functional theory (DFT) calculations are performed to study the effects of alloying element Cr and Ti on the stability of Xn-vacancy1 (XnVa1) complexes (X=C, N, O, and n=1, 2) and the diffusivity of inherent X impurity nearby Cr or Ti in vanadium (V). The presence of alloying element Cr reduces the stability of X atom in the octahedral interstitial site (O-site) according to the calculated formation energies, and the stability decreases with increasing the number of Cr atoms. We find that the number of the added Ti atoms below four is beneficial for X stability in O-site, while against the X stability with the number of Ti atoms from 5 to 6. The binding energies of X-Va1Cr/Ti and X-XVa1Cr/Ti are investigated, and the results show that Cr weakens the repulsive interaction of C/N-Va1Cr pairs, but enhances the attractive interaction of O-Va1Cr and X-XVa1Cr pairs. The addition of Ti is beneficial for Va1Ti trapping one and two C/O atoms to form Cn/OnVa1Ti clusters (n=1, 2). The migration barriers of C and N nearby Cr are lower than those in pure vanadium, while that of O is higher. However, the opposed trend is observed in the case of nearby Ti. These findings improve our understanding about the behavior of X atoms in vanadium with influence of Cr and Ti under irradiation environment.

Bacteria play a critical role in carbon cycling and nutrient remineralization. To reveal potential mechanisms controlling bacterial abundance in the upper 200 m of the South China Sea (SCS), the generalized linear model (GLM), generalized additive model (GAM) and generalized boosted model (GBM) were constructed to address the relationship between bacterial abundance and environmental factors, including geographical variables, biotic variables and water chemistry. GAM and GBM were found suitable for modeling bacterial abundance in the SCS. The predictive performance of GBM was superior to GLM and GAM for bacterial distribution. In addition, bacterial abundance predicted by GBM from environmental parameters was highly consistent with the observations, indicating that GBM was robust to predict bacterial abundance from environmental parameters. Furthermore, the key environmental factors modulating the horizontal and vertical distribution of bacteria were determined based on models. Horizontally, surface bacterial abundance decreased from onshore to offshore, which was primarily regulated by salinity and chlorophyll-a. Vertically, bacterial abundance decreased with depth. Chlorophyll-a was primarily responsible for vertical variability in bacterial abundance in the upper 100 m, where temperature was higher than the optimum temperature (21 °C) for bacterial growth. In contrast, temperature was a dominant factor regulating bacterial abundance below 100 m, where temperature was below 21 °C and positively correlated with BA. Viruses and nutrients played less important roles in regulating bacterial abundance than chlorophyll-a and temperature in the SCS. Our models elucidated environmental regulations on bacterial abundance, which was helpful for us to understand bacterial carbon cycling in the SCS.

The phosphorus cycle is studied during 2013–2014 in the Sanggou Bay (SGB), which is a typical aquaculture area in northern China. The forms of measured phosphorus include dissolved inorganic phosphorus (DIP), dissolved organic phosphorus (DOP), particulate inorganic phosphorus (PIP), and particulate organic phosphorus (POP). DIP and PIP are the major forms of total dissolved phosphorus (TDP) and total particulate phosphorus (TPP), representing 51%–75% and 53%–80%, respectively. The concentrations and distributions of phosphorus forms vary among seasons relative to aquaculture cycles, fluvial input, and hydrodynamic conditions. In autumn the concentration of DIP is significantly higher than in other seasons (P

First-principles calculations have been performed to study the effect of C on the stacking fault energy (SFE) of paramagnetic γ -Fe and Fe Cr Ni austenitic steel. In these systems, the local magnetic structure is very sensitive to the volume in both fcc and hcp structures, which emphasizes the importance of the magnetovolume coupling effect on the SFE. The presence of C atom suppresses the local magnetic moments of Fe atoms in the first coordination shell of C. Compared to the hypothetical nonmagnetic case, paramagnetism significantly reduces the effect of C on the SFE. In the scenario of C being depleted from the stacking fault structure or twin boundaries, e.g. , due to elevated temperature, where the chemical effect of C is dissipated, we calculate the C-induced volume expansion effect on the SFE. The volume induced change in the SFE corresponds to more than ∼ 50% of the total C effect on the SFE obtained assuming uniform C distribution.

Density functional theory calculations have been performed to study the effects of alloying Cr and W on the stability and diffusivity of interstitial He impurity in body-centered cubic (bcc) Fe host lattice. The interaction between two close Cr/W atoms is repulsive. The relative stable position for an interstitial He remains the tetrahedral interstitial site in the presence Cr. Energetically, He prefers to locate far away from W inside Fe host lattice due to the strong repulsive interaction between He and W. On the other hand, the He migration barrier becomes lower in the presence of Cr (0.026 eV) and W (0.049 eV), as compared to 0.059 eV for pure Fe. Addition of Cr is benefit for He self-trapping, while W is against. The effective diffusivity of He decreases with increasing Cr and W concentrations. Moreover, the additions of Cr and W slightly hinder He being trapped by monovacancy.

Field observations were made from 2012 to 2014 at an integrated multi-trophic aquaculture (IMTA) site in Sanggou Bay (SGB), China, to characterize the nutrients associated with aquaculture activities, and to assess the effects of aquaculture on nutrient cycles in the bay. Dissolved inorganic and organic nutrient levels were measured in rivers, groundwater, and SGB. Seasonal variations in nutrient concentrations were detected in the rivers, particularly enrichment of dissolved inorganic nitrogen (DIN) and silicate (DSi). Nutrient concentrations showed considerable seasonal variation, with higher and significantly different concentrations occurring in autumn than in the other seasons. The composition and distribution of nutrients were also affected by the species being cultured. Dissolved organic nitrogen and phosphorus (DON and DOP) accounted for 27 to 87% of total dissolved nitrogen and 34 to 81% of total dissolved phosphorus, respectively. Phosphorus may be a potentially limiting nutrient for phytoplankton growth in summer. Nutrient budgets were developed based on a simple steady-state box model. These showed that bivalve aquaculture was the major source of PO43- (contributing 64% of total influx) and led to increased riverine fluxes of PO43-. The results indicated that substantial quantities of nitrogen and DSi accumulated in sediments or were transformed into other forms (e.g. phytoplankton cell composition or particles). Large quantities of DIN and PO43- were removed from the bay through harvesting of seaweeds and bivalves, which represented up to 64 and 81% of total outflux, respectively. The results show that aquaculture activities play the most important role in nutrient cycling in SGB.

Benthic nutrient fluxes in an integrated multi-trophic aquaculture (IMTA) bay— Sanggou Bay, China—were measured in June and September 2012. The benthic nutrient fluxes and total organic carbon (TOC) of sediment in this IMTA system were significantly lower than in monoculture bays. This was due to the efficient recycling of organic matter in the IMTA system, as revealed by historical data of annual production, dissolved inorganic nitrogen (DIN) concentra- tion in seawater and TOC in sediment. Benthic nutrient fluxes in the IMTA system were mainly controlled by seawater temperature, dissolved oxygen (DO) and nutrient concentrations, which were strongly related to aquaculture activities. In June, the early growth phase of cultured finfish and bivalves contributed little to biodeposition, and benthic nutrient fluxes tended to be from the sediment to the seawater and contributed to algal growth. In September, the active growth of finfish and bivalves resulted in high concentrations of nutrients in the seawater and TOC in the sediment; 64% of the nitrogen and 25% of the phosphorus metabolized by bivalves were trans- ferred from the seawater to the sediment.

Rapid advancements in flexible and multifunctional electronics bring challenges to the corresponding power suppliers. Soft triboelectric nanogenerator (TENG), as a promising route to satisfy the demands of various self-powered sources and energy harvesting devices, has been developed in this study via facile all-printing method. The nanogenerator features a thin film with micro patterned friction silicone layers, which is fabricated through direct ink writing technology. Wrinkled silver electrode is sandwiched and protected by silicone layers, and constructed through prestrain, release, and buckling process based on inkjet printing technology. As an experimental result, TENG with 100% prestrain produces the maximum output voltage of 44.16 V at the frequency of 5 Hz and external force of 10 N, higher than the pristine nanogenerator. The output voltage of these TENGs could be enhanced slightly when it is stretched to a certain degree. The as-prepared TENG can work for biomechanical energy harvesting driven by human motions and instantaneously power 20 commercial Light Emitting Diodes (LEDs). Moreover, the all-printed soft TENG arrays show potential applications in tactile sensor for touch perception. Our work opens a new idea for fabrication of flexible and wearable TENG based on printing technology to shorten fabrication cycle, simplify individual design and make it more accessible for practical application.

A series of flow-through reactor experiments were undertaken to assess the potential effect of porewater advection and dissolved inorganic phosphorus (DIP) concentration on benthic DIP dynamics in permeable sediments collected from the Weizhou Island, northern South China Sea. The flux of DIP ranged from −0.13 to 0.05 mmol m−2 h−1, and the reversal from DIP efflux to influx occurred when the DIP concentration reached a threshold. DIP release from the sediment into the seawater peaked at intermediate advection rate, which perhaps provide optimum conditions for DIP release related to CaCO3 dissolution. Phosphorus limitation in seawater could be relieved by DIP release from the sediment, and CaCO3-bound P in carbonate sands may play a major role in benthic DIP release and decrease in the molar nitrogen/phosphorus ratio in seawater around the Weizhou Island.

China is the largest mariculture producer in the world, but detailed information on the spatiotemporal variations of biogenic elements and sources of sedimentary organic matter (SOM) via mariculture is limited. The primary objective of this study was to assess the influence of mariculture on the origin of SOM in relation with biogenic elements and geochemical paramaters due to the importance of SOM as a potential source of nutrients and energy in coastal marine environments. Surface sediments from the Maowei Sea were collected in August (summer) and December (winter), 2016 for grain size, total organic carbon (TOC), total nitrogen (TN), organic phosphorus (OP), biogenic silica (BSi), δ13C and δ15N analyses. Significant correlation (p 40% of the deposited SOM originates from terrestrial source during two seasons. The SOM from shellfish mariculture was seasonal, mainly deposited in the intensive mariculture areas, and its proportions were only higher than contributions from marine plankton in summer. Generally, this study indicates that shellfish biodepositions can significantly influence the cycle of carbon and other biogenic elements in the intensive mariculture areas. Nevertheless, the overall dominance of terrestrial and marine SOM suggests that the sources of SOM and factors influencing carbon cycling in the Maowei Sea do not exclusively depend on the intensity of mariculture activities.

Due to the potential utilization of ZrC in advanced nuclear reactors, it is important to understand the behavior of intrinsic defects and fission gas products. In this study, the energetics of intrinsic defects (i.e. monovacancy, self-interstitial, anti-site defect, Frenkel pair, Schottky defect and divacancy), the incorporation and migration of single noble gas atom (Ng = He, Ne, Ar and Kr), the atomic configuration of small noble gas clusters (Ngn) and Ngn-vacancies complexes have been systemically investigating by ab initio calculations. Carbon atoms escape from the lattice site easily and then form vacancy, interstitial or Frenkel pairs, while the formations of Zr vacancy and interstitial cost more energy and the presence of Zr vacancy would induce a new C vacancy along direction. Due to the higher formation energy, anti-site defects are not expected to be the dominant defect in ZrC. The formation energy of Ng atom increases linearly with the atomic numbers (thus atomic radius) of Ng; meanwhile, the lattice distortion is also more pronounced. The lowest diffusion barrier of Ng atom is found on the path from one interstitial site to an adjacent one along direction. The nearest distance and the corresponding binding energy between Ng-Ng pair gradually increase with the atomic radius, meaning that Ng atoms tend to aggregate in ZrC crystal. In addition, existence of the monovacany, divacancy and Schottky defect (especially Zr vacancy) considerably reduces the formation energies of Ngn clusters.

Dissolved organic carbon concentration in the Pearl River estuary (PRE) of China was measured in May, August, and October 2015 and January 2016. Chromophoric and fluorescent dissolved organic matter (CDOM and FDOM) in the latter three seasons were characterized by absorption and fluorescence spectroscopy. Parallel factor analysis of the fluorescence spectra identified two protein-like, two humic-like, and one oxidized quinone-like FDOM components. The seasonality of average DOM abundance varied as follows: DOC: May (156 μmol L−1) > January (114 μmol L−1) ≈ August (112 μmol L−1) > November (86 μmol L−1); CDOM absorption at 330 nm: August (1.76 m−1) > November (1.39 m−1) ≈ January (1.30 m−1); FDOM expressed as the sum of the maximum fluorescence intensities of all FDOM components: November (1.77 R.U.) > August (1.54 R.U.) ≈ January (1.49 R.U.). Average DOM abundance in surface water was higher than in bottom water, their difference being marginal (0.1–10 %) for DOC in all seasons and for CDOM and FDOM in November and January, and moderate (16–21 %) for CDOM and FDOM in August. DOC showed little cross-estuary variations in all seasons while CDOM and FDOM in January were higher on the west side of the estuary than in the middle and on the east side. All three variables exhibited large variations and/or rapid drawdowns at the head of the estuary (salinity a330) into the South China Sea were estimated as 195 × 109 g and 266 × 109 m2 for the PRE, and 362 × 109 g and 493 × 109 m2 for the entire Pearl River Delta. Compared to other world major estuaries, the PRE presents the lowest concentrations and export fluxes of DOC and CDOM. Nonetheless, DOM delivered by the PRE is protein-rich and thus may significantly impact the local ecosystem.

The coupling of the carbon and nutrient cycles drives the food web structure and biogeochemistry of ecosystems. However, across precipitation gradients, there may be a shift in C and N pools from above- to belowground because of shifting plant stoichiometry and allocation. Here, we present a study which is the first to explicitly compare above- and belowground pool sizes of N and C within predominant plant species along precipitation gradient. We dissected these pools into biomass allocation and nutrient concentrations. Based on previous evidence, biomass allocation to roots should increase with aridity, while leaf [N] should increase. If their effect sizes are equal, they should cancel each other out, and the above- and belowground proportions of the N would remain constant. Along a precipitation gradient in Chinese steppe zone, the effect sizes of the biomass shifts were remarkably consistent among the predominant species, Stipa grandis. The effect sizes of biomass allocation and [N] were equal and the proportion of N of above- and belowground did not change with aridity, but the shift in leaf [C] with aridity was much weaker than the biomass shift, leading to a decrease in the proportion of C belowground at dry sites. Precipitation gradients do decouple the C and N pool of S. grandis along a precipitation gradient in Chinese steppe zone.

Plasma technology is applied in various fields, which involves in stimulating the germinability and amelioration of crop seeds, increasing crop production and displaying high quality, stress tolerance and other beneficial traits. Crucial techniques of plasma treating seeds (PTS) are introduced and the technical applications of activating seeds with key parameters of plasma discharge equipment are discussed. With a lot of laboratory researches and field tests, the biological effects of non-thermal PTS are analyzed. Meanwhile, a preliminary discussion about the PTS mechanism and technical popularization is made. Main findings including non-thermal plasma treatment are as follows: (i) the germination rates of the maize seeds were 72% or so if treated by 140 W–160 W power, which was the highest; (ii) the length of the wheat radicle and germ was increased effectively by 8.7 cm and 3.3 cm, and the dry weight of the wheat was increased by 10.1%; (iii) the germinative energy and germinating percentage of the aging seeds could be greatly increased. It is concluded that PTS enhances seed germination as well as plant growth, meanwhile, more crops are yielded and the quality is improved. Both technologies and plasma discharge equipment have significant applicative value and popularize in agriculture.

Reduced activation ferritic/martensitic (RAFM) steels are structural materials with potential application in Generation-IV fission and fusion reactors. We use density-functional theory to scrutinize the micro-mechanical properties of the main alloy phases of three RAFM steels based on the body-centered cubic FeCrWVMn solid solution. We assess the lattice parameters and elastic properties of ferromagnetic $\alpha$-Fe and Fe$_{91}$Cr$_{9}$, which are the main building blocks of the RAFM steels, and present a detailed analysis of the calculated alloying effects of V, Cr, Mn, and W on the mechanical properties of Fe$_{91}$Cr$_{9}$. The composition dependence of the elastic parameters is decomposed into electronic and volumetric contributions and studied for alloying levels that cover the typical intervals in RAFM steels. A linear superposition of the individual solute effects on the properties of Fe$_{91}$Cr$_{9}$ is shown to provide an excellent approximation for the \emph{ab initio} values obtained for the RAFM steels. The intrinsic ductility is evaluated through Rice's phenomenological theory using the surface and unstable stacking fault energies, and the predictions are contrasted with those obtained by empirical criteria. Alloying with V or W is found to enhance the ductility, whereas additional Cr or Mn turns the RAFM base alloys more brittle., Comment: 29 pages, 4 figures