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The cell wall is the most striking feature that distinguishes plant cells from animal cells. It plays an essential role in cell shape, stability, growth and protection. Despite being present in small amounts, cell wall proteins (CWPs) are crucial components of the cell wall. The cell wall proteome generally consists of sensu stricto CWPs, apoplast proteins and extracellular secreted proteins. Currently, there is a need for the bioinformatics analysis of a tremendous number of protein sequences that have been generated from genomic, transcriptomic and proteomics research. Compared with intracellular proteins, the location prediction of CWPs is challenging because many aspects of these proteins have not been experimentally characterized, and there are no CWP-trained, specific predictors available. By introducing the biological relevance (particularly molecular aspects) of the cell wall and CWPs, we critically evaluated the accuracy of 16 state-of-the-art predictors and classical predictors for the prediction of CWPs using an independent database of Arabidopsis and rice proteins. All experimentally verified CWPs and non-CWPs were retrieved from the UniProt Knowledgebase. Based on the evaluation, we currently recommend the predictors mGOASVM, HybridGO-Loc and FUEL-mLoc for CWPs. Furthermore, we outlined the public databases that can be used to cross-reference the subcellular location of CWPs. We illustrate a flowchart of the subcellular location prediction and a cross-reference of possible CWPs. Finally, we discuss challenges and perspectives in the bioinformatics analysis of CWPs. It is hoped that this article will provide practical guidance regarding CWPs for nonspecialists and provide insight for bioinformatics experts to develop computational tools for CWPs. [ABSTRACT FROM AUTHOR]

Five new diterpenes including four diterpenes with 1,2,3,4,4a,5,6,8a-octalin skeleton talaroacids A–D (1–4) and an isopimarane diterpenoid talaromarane A (5) were isolated from the mangrove endophytic fungus Talaromyces sp. JNQQJ-4. Their structures and absolute configurations were determined by analysis of high-resolution electrospray ionization mass spectroscopy (HRESIMS), 1D/2D Nuclear Magnetic Resonance (NMR) spectra, single-crystal X-ray diffraction, quantum chemical calculation, and electronic circular dichroism (ECD). Talaromarane A (5) contains a rare 2-oxabicyclo [3.2.1] octan moiety in isopimarane diterpenoids. In bioassays, compounds 1, 2, 4, and 5 displayed significant anti-inflammatory activities with the IC50 value from 4.59 to 21.60 μM. [ABSTRACT FROM AUTHOR]

Formaldehyde (HCHO), a key aerosol precursor, plays a significant role in atmospheric photo-oxidation pathways. In this study, HCHO column densities were measured using a Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) instrument at the University of Chinese Academy of Science (UCAS) in Huairou District, Beijing, which is about 50 km away from the city center. Measurements were taken during the period of 1 October 2014 to 31 December 2014, and the Asia-Pacific Economic Cooperation (APEC) summit was organized on 5–11 November. Peak values of HCHO vertical column densities (VCDs) around noon and a good correlation coefficient R2 of 0.73 between HCHO VCDs and surface O3 concentration during noontime indicated that the secondary sources of HCHO through photochemical reactions of volatile organic compounds (VOCs) dominated the HCHO values in the area around UCAS. Dependences of HCHO VCDs on wind fields and backward trajectories were identified and indicated that the HCHO values in the area around UCAS were considerably affected by the transport of pollutants (VOCs) from polluted areas in the south. The effects of control measures on HCHO VCDs during the APEC period were evaluated. During the period of the APEC conference, the average HCHO VCDs were ∼38%±20% and ∼30%±24% lower than that during the pre-APEC and post-APEC periods calculated at the 95 % confidence limit, respectively. This phenomenon could be attributed to both the effects of prevailing northwest wind fields during APEC and strict control measures. We also compared the MAX-DOAS results with the Copernicus Atmosphere Monitoring Service (CAMS) model. The HCHO VCDs of the CAMS model and MAX-DOAS were generally consistent with a correlation coefficient R2 greater than 0.68. The peak values were consistently captured by both data datasets, but the low values were systematically underestimated by the CAMS model. This finding may indicate that the CAMS model can adequately simulate the effects of the transport and the secondary sources of HCHO but underestimates the local primary sources. [ABSTRACT FROM AUTHOR]

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Study on the relationships between grain production and cultivated land productivity and its regional difference is of great significance for food security. Besides, it is also important for finding regional potential yields of grain, improving the utilization efficiency of cultivated land resources and achieving the regional increase of grain yield. In this paper, on the basis of agro-ecological zoning (AEZ) model, a new method was proposed to calculate the cultivated land productivity under cultivated land quality modification. Furthermore, the modification of cultivated land quality was based on a new concept that the quality of cultivated land was not only affected by natural factors but also by artificial factors such as irrigation canals, greenhouse, nursery factory, mechanical facilities and its supporting service station. By discussing the conceptual system of cultivated land integrated productivity which took the potential quantity of cultivated land and the quality index of cultivated land into the consideration, we proposed that comprehensive productivity of cultivated land was the maximum sustainable production capacity for food under the certain economic and technological conditions, and it was strongly affected by the quality and quantity of cultivated land. Additionally, according to the concept, we built a model which can reveal the relationship between grain production and cultivated land productivity. This model was made up of comprehensive yield and productivity index of cultivated land (CLYPCI), cultivated land quality productivity index (CLQLPI), and cultivated land quantity productivity index (CLQNPI). The CLYPCI was used to measure the efficiency of cultivated land grain production and to reveal the relationship between actual output of grain and cultivated land productivity in a particular area. The CLQLPI was used to describe the average output efficiency of a regional cultivated land. The CLQNPI was used to measure the degree of exploitation and utilization of cultivated land in terms of quantity. This model was constructed based on the improved AEZ model, so it was only suitable for researching the relationship between grain production and cultivated land productivity at large or medium scales. At last, in this paper Quzhou county was used as a case study for model validation. The value of CLYPCI, CLQLPI and CLQNPI was 0.16, 0.31, 0.99, respectively in Quzhou. The results showed that the output efficiency and the average development level of cultivated land were not high in general. The potential of increased quantity of cultivated land was low, but the potential of increased yield of cultivated land was high. Compared with the cultivated land comprehensive productivity (CLCP), the CLYPCI value of different towns was reduced with CLCP which was sorted from the largest to smallest except Disituan town. The output of cultivated land was proportional to its productive capacity by comparing CLCP and CLYPCI of various towns. In addition, the value of CLQLPI and CLQNPI of different towns were very similar. The CLQLPI of 10 towns fluctuated around 0.31 which was the average value of CLQLPI of Quzhou. The CLQLPI in Yizhuang was the highest. The CLQNPI of 10 towns fluctuated around 0.99 and there were six towns whose CLQNPI value was 0.99. The CLQNPI of Yizhuang was also the highest. There was little chance to increase the quantity of cultivated land for Yizhuang. [ABSTRACT FROM AUTHOR]

To deeply understand the quantity, quality, spatial distribution characteristics and the representative of cultivated land of national standard farmland in western China at macro scale, it is very important to set up and improve the monitoring system of cultivated land quality in the whole country. This paper, based on the database of farmland classification and national standard farmland in western China (12 provinces, municipalities and autonomous regions), gives a analysis of the quantitative distribution characteristic of national standard farmland of the western region in gradation (quality) and on a secondary zone of the standard farming system. The paper then analyzes the spatial distribution features of standard farmland based on GIS and conducts inspection, definition and statistical tests for the representative of national standard farmland. Results show that: (1) In the view of quantitative distribution characteristics, national standard farmlands of the western China were distributed across all the gradations 4-15, but exhibited great differences in each gradation, such as more than half of them concentrated in 8-12 gradation. The distribution of national standard farmland in the 4, 5, 14, and 15 grades was less. Furthermore, national standard farmlands of the western China are unevenly distributed in the secondary zone and have not covered 28 secondary zones of the standard farming system. Therefore, there exists cultivated land but no national standard farmland in five secondary zones such as Daxing'an Mountains region and so on. (2) From the spatial distribution characteristics, national standard farmland is uniformly distributed on the whole, but there is a significant spatial difference and there exist excessive concentration phenomena in six secondary zones. Thus, the data presented suggest that we should adjust and optimize the monitoring sample plot layout of national standard farmland in western China, according to a comprehensive analysis of the testing results and the distribution characteristics. [ABSTRACT FROM AUTHOR]

Food security always attracts strong attention from researchers and policy makers in China, because it has more than one fifth of the world's population, but the total cultivated area accounts for only about seven percent of the world's total cultivated area. However, relevant studies were normally conducted at the national level, which generally considered China's food security as a whole or used a single index system set for analysis. Therefore, study on food security from a regional scale will be of great value for policy makers. Grain production guarantee capacity of regional cultivated land is the satisfaction degree of regional grain supply to meet the national grain demand, which is mainly influenced by local cultivated land resources, cropping systems, and socio-economic factors. Regional total grain demand should be measured from a national perspective because of the mobility of grain and population; more specifically, it should be calculated based on the proportion of regional resource endowments in the national total endowments. In this paper, a framework is proposed to evaluate regional grain production capacity and the corresponding security level, and the Grey System Model is used to estimate regional grain production capacity under three different scenarios (normal harvest years, bad harvest years, and good harvest years) based on the historical grain production levels. After that, scenarios are selected that could meet the national grain demand and divide the risks of grain production guarantee capacity into four grades, i.e., low risk, small risk, medium risk, and high risk. To test this approach, the Dongting Lake area (located in the northeastern part of Hunan province) was chosen as the case study area, and 2020 was selected as the predicted year. The results show that the risk level of grain production guarantee capacity of the Dongting Lake area is low risk under normal conditions, which means the grain production capacity of the Dongting Lake area can meet the national grain demand in bad harvest years. Judging from the spatial distribution, the areas closer to the lake have a higher risk grade than the other areas. This is partly because the areas are rich in water resources so some farmers tend to give up grain planting in favor of fishpond operations, which makes cultivated land decrease. On the other hand, because of the geographic location of this area, some accidental factors, such as the natural climate, have great influence on grain yield and exhibit considerable variation, which also causes the gap among grain production guarantee capacities to increase at different times. These condition results in a relative high risk of grain production guarantee capacity in this area. On the whole, the grain production guarantee capacity of the Dongting Lake area is optimistic in the near future, but the risks of grain production guarantee capacity of some counties are high. Therefore, relevant policies should be put forward to improve this situation. The method proposed in this paper can provide a novel way to study the relationship between the grain security situation and cultivated land resources in different areas. [ABSTRACT FROM AUTHOR]

Trichinella spiralis serpin-type serine protease inhibitors (TsSPIs) are expressed in adult worms (AW), newborn larvae (NBL) and muscle larvae (ML) of T. spiralis, with the ML stage demonstrating the highest expression level. This study aims to determine TsSPI functions in larval viability and invasion of intestinal epithelial cells in vitro, as well as their development, survival, and fecundity in vivo via RNAi. TsSPI-specific siRNAs and dsRNA were transfected into ML by incubation. The silencing effect of TsSPI transcription and expression was determined using qPCR and western blot, respectively. After incubation in 60 ng/μL dsRNA–TsSPI for 3 days, larval TsSPI mRNA and protein expression levels were reduced by 68.7% and 68.4% (P < 0.05), respectively. dsRNA-mediated silencing of TsSPI significantly impacted larval invasion into intestinal epithelial cells in vitro but did not affect the survival rate of larvae. After challenge with dsRNA–TsSPI-treated ML, mice exhibited a 56.0% reduction in intestinal AW burden and 56.9% reduction in ML burden (P < 0.05), but NBL production of female AW remained the same (P > 0.05). Our results revealed that RNAi-mediated silencing of TsSPI expression in T. spiralis significantly reduced larval infectivity and survival in the host but had no effect on the survival rate and fecundity. Furthermore, TsSPIs have no effect on the growth and reproduction of parasites but may be directly involved in regulating the interaction of T. spiralis and the host. Therefore, TsSPIs are crucial in the process of T. spiralis larval invasion and parasite survival in the host. [ABSTRACT FROM AUTHOR]