Comparison of Gross Primary Productivity Derived from GIMMS NDVI3g, GIMMS, and MODIS in Southeast Asia

Gross primary production (GPP) plays an important role in the net ecosystem exchange of CO2 between the atmosphere and terrestrial ecosystems. It is particularly important to monitor GPP in Southeast Asia because of increasing rates of tropical forest degradation and deforestation in the region in recent decades. The newly available, improved, third generation Normalized Difference Vegetation Index (NDVI3g) from the Global Inventory Modelling and Mapping Studies (GIMMS) group provides a long temporal dataset, from July 1981 to December 2011, for terrestrial carbon cycle and climate response research. However, GIMMS NDVI3g-based GPP estimates are not yet available. We applied the GLOPEM-CEVSA model, which integrates an ecosystem process model and a production efficiency model, to estimate GPP in Southeast Asia based on three independent results of the fraction of photosynthetically active radiation absorbed by vegetation (FPAR) from GIMMS NDVI3g (GPPNDVI3g), GIMMS NDVI1g (GPPNDVI1g), and the Moderate Resolution Imaging Spectroradiometer (MODIS) MOD15A2 FPAR product (GPPMOD15). The GPP results were validated using ground data from eddy flux towers located in different forest biomes, and comparisons were made among the three GPPs as well as the MOD17A2 GPP products (GPPMOD17). Based on validation with flux tower derived GPP estimates the results show that GPPNDVI3g is more accurate than GPPNDVI1g and is comparable in accuracy with GPPMOD15. In addition, GPPNDVI3g and GPPMOD15 have good spatial-temporal consistency. Our results indicate that GIMMS NDVI3g is an effective dataset for regional GPP simulation in Southeast Asia, capable of accurately tracking the variation and trends in long-term terrestrial ecosystem GPP dynamics

Evidence Of Protein Collective Motions On The Picosecond Time Scale

We investigate the presence of structural collective motions on a picosecond time scale for the heme protein, cytochrome c, as a function of oxidation and hydration, using terahertz (THz) time-domain spectroscopy and molecular dynamics simulations. The THz response dramatically increases with oxidation, with the largest increase for lowest hydrations and highest frequencies. For both oxidation states the THz response rapidly increases with hydration saturating above ~25% (g H2O/g protein). Quasi-harmonic vibrational modes and dipole-dipole correlation functions are calculated from molecular dynamics trajectories. The collective mode density of states alone reproduces the measured hydration dependence providing strong evidence of the existence of these motions. The large oxidation dependence is reproduced only by the dipole-dipole correlation function, indicating the contrast arises from diffusive motions consistent with structural changes occurring in the vicinity of a buried internal water molecule

Genome-wide identification and expression analysis of calmodulin-like proteins in cucumber

Background The calmodulin-like (CML) protein is a crucial Ca2+-binding protein that can sense and conduct the Ca2+ signal in response to extracellular stimuli. The CML protein families have been identified and characterized in many species. Nevertheless, scarce information on cucumber CML is retrievable. Methods In this study, bioinformatic analyses, including gene structure, conserved domain, phylogenetic relationship, chromosome distribution, and gene synteny, were comprehensively performed to identify and characterize CsCML gene members. Spatiotemporal expression analysis in different organs and environment conditions were assayed with real-time quantitative polymerase chain reaction (qRT-PCR). Results Forty-four CsCMLs family members were well characterized, and the results showed that the 44 CsCML proteins contained one to four EF-hand domains without other functional domains. Most of the CsCML proteins were intron-less and unevenly distributed on seven chromosomes; two tandemly duplicated gene pairs and three segmentally duplicated gene pairs were identified in the cucumber genome. Cis-acting element analysis showed that the hormone, stress, and plant growth and development-related elements were in the promotor regions. In addition, spatiotemporal expression analysis revealed distinctive expression patterns for CsCML genes in different tissues and environmental conditions, and a putative protein interaction network also confirmed their potential role in responding to various stimuli. These results provide a foundation for understanding CsCMLs and provide a theoretical basis for further study of the physiological functions of CsCMLs

Methyl jasmonate treatment alleviates chilling injury and improves antioxidant system of okra pod during cold storage

Abstract Okra pod is sensitive to low temperature, which results in chilling injury under improper low‐temperature storage. This study aimed to evaluate the effect of different concentrations of methyl jasmonate (MeJA) treatment on okra pod stored at 4 ± 1°C for 12 days and illuminate the mechanism of MeJA alleviating chilling injury. Compared to the control, MeJA treatments maintained lower relative electric conductivity (REC), chilling injury (CI) degree, and lignin content, as well as higher total soluble solids, total soluble sugar, pectin content, and chlorophyll content. The factor analysis was applied to comprehensively evaluate the effects of MeJA so that 1 μmol/L MeJA was screened as the optimum concentration to maintain the okra quality throughout the storage time. In contrast with control, MeJA not only accelerated the generation of antioxidant substances (phenolics and flavonoids) but also increased the superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD) activity, inhibited malondialdehyde (MDA), hydrogen peroxide (H2O2) content accumulation, and the polyphenol oxidase (PPO) activity. This work confirmed that MeJA could effectively alleviate chilling injury and maintain the quality during cold‐stored by regulating reactive oxygen species (ROS) metabolism. These results provide theoretical guidance for the application of MeJA in okra storage and preservation

Overexpression of BAS1 in rice blast fungus can promote blast fungus growth, sporulation and virulence in planta

Background: BAS1 is biotrophy-associated secreted protein of rice blast strain (Magnaporthe oryzae). In order to study the effect of BAS1 on virulence of rice blast strain, we characterized function of BAS1 using a purified prokaryotic expression product of BAS1 and its overexpression strain. Results: Our results showed in vitro the purified expression product caused rapid callose deposition and ROS production in rice leaves and calli, indicated it triggered transient basal defense. When the purified expression product of BAS1 was sprayed onto rice leaves, and 24 h later the leaves were inoculated with blast strain, the results showed the size and number of lesions, on purified BAS1 product-pretreated leaves of the Lijiangxintuanheigu (LTH) challenged with blast strain, was higher than those in BAS1-untreated leaves directly challenged with the same strain, which suggested the defense response trigged by BAS1 can be overcome by other effectors of the fungus. More severe symptoms, higher sporulation, higher relative fungal growth and more lower expression level of defense-related genes appeared in LTH leaves challenged with overexpression strain 35S:BAS1/Mo-2 than those in LTH inoculated with wild-type strain. Conclusions: These data suggest both in vitro pretreatment with BAS1 prokaryotic expression products and overexpression in blast strains can increase virulence of blast fungus

Nitric oxide alleviates chilling injury in cucumber (Cucumis sativus L.) fruit by regulating membrane lipid and energy metabolism

ABSTRACTChilling injury is the dominant factor for quality deterioration and marketability suffers of cucumber fruit during low-temperature storage. Nitric oxide (NO) is a kind of endogenous signaling molecule that significantly regulates the abiotic stress response. In the current investigation, the membrane lipid and energy metabolism were investigated after cucumber fruit was exposed to a sodium nitropruside (SNP) solution that acts as a NO donor before being kept at 4°C for 12 days. The results illustrated that SNP treatment reduced chilling injury and lightened the increase in membrane permeability under cold stress, maintaining a better quality. Subsequently, SNP regulated lipid metabolism by reducing the expression of genes encoding PLA, PLD, lipase, and LOX and decreasing the activities. Compared to the control, the SNP-treated fruit exhibited higher ATP and EC (energy charge) levels. Moreover, SNP-treated suppressed the decrease of H+-ATPase, Ca2+-ATPase, SDH, and CCO activity, which is involved in energy metabolism. The above results showed that exogenous nitric oxide might be an effective method to alleviate the chilling damage in postharvest cucumber fruit by modifying membrane lipids and energy metabolism

Seasonal variation of CO<inf>2</inf> flux and its environmental factors in evergreen coniferous plantation

The effects of environmental factors on carbon flux were analyzed, the spatial and temporal variation of carbon flux was studied at the two heights of 23 m and 39 m with the eddy covariance technique, and the carbon budget was evaluated for evergreen coniferous plantation in the red earth hilly area during the year 2003. The results showed that photosynthetically active radiation (PAR) and soil temperature are essential factors strongly affecting the net ecosystem exchange (NEE); in the daytime, the response of NEE to PAR shows a rectangular hyperbola trend, and in the nighttime, the significant correlation was observed between soil temperature and soil respiration which was filtered using friction velocity. This ecosystem appeared as a carbon sink along the whole year of 2003, and the carbon flux showed the obvious seasonal fluctuation and diurnal variability. The seasonal peak of NEE occurred in May and June with the daily sum about 0.61 - 0.67 mg &middot CO<inf>2</inf> &middot m ^-2 &middot s^-1. For the severe drought in the mid-summer, the daily sum was 0.40 - 0.44 mg &middot CO<inf>2</inf> &middot m ^-2 &middot s^-1 in July which was only 2/3 of that in the last two months. For the lasted drought of the year, the nadir of NEE happened in the winder with the daily sum about -0.29 to -0.35 mg &middot CO2 &middot m^-2 &middot s^-1. The sink intensity of the ecosystem was about -0.553 to -0.645 kg &middot Cm^-2 per year in 2003. Copyright by Science in China Press 2005

Effect of 2,4-D pre-treatment on quality during ripening of on-tree longan fruit

The aim of this study was to investigate the effect of 20 mg/L 2,4-D on the quality during ripening of on-tree longan fruits. We investigated external and internal properties of the on-tree longan fruits. The results showed that 2,4-D treatment promotes the growth based on the fruit size and weight. The respiration rate, contents of TSS, total soluble sugar, sucrose, glucose, fructose, and hexose revealed an increasing tendency with advancing the maturity and reached the high status during 110-126DPA. By contrast, the relative electric conductivity and TA content displayed a declining trend during the ripening stage, increase with the senescence. All these pieces of information indicated that 2,4-D treatment could effectively promote the sensory quality of on-tree longan fruit, prolong the harvest time to 118DPA, while CK should harvest before 110DPA

Expression and Clinical Significance of the Thyroid Transcription Factor 1 in Xuanwei Lung Adenocarcinoma

Background and objective The present study aims to detect the expressions of the thyroid transcription factor 1 (TTF-1) mRNA and protein in Xuanwei lung adenocarcinoma line (XWLC-05). We also investigated the relationship of TTF-1 with Ki-67 protein and analyzed the prognostic value of the TTF-1 protein in Xuanwei lung adenocarcinoma patients. Methods The expression of TTF-1 mRNA was evaluated by quantitative real-time RT-PCR (qRT-PCR), while proteins of TTF-1 and Ki-67 were detected by immunohistochemistry in XWLC-05. The expressions of TTF-1 and Ki-67 was detected in 96 resected cases of Xuanwei lung adenocarcinoma by immunohistochemistry from January 2008 to March 2012. Results TTF-1 mRNA was low and protein was absent in XWLC-05. The expression of Ki67 protein was 100% (high proliferative activity) in XWLC-05. All samples were Xuanwei lung adenocarcinoma (n=96) and TNM stages were I-II 66% (63/96) and III 34% (33/96). Immunohistochemical analysis showed the expression of TTF-1 in 89 (93%) of 96 and Ki-67 in 69 (70%) of 96. The positive rate of TTF-1 protein was 38 (96%) of 39 in well-differentiated phenotype and 51 (89%) 57 in moderately/poorly-differentiated phenotype. Patients with strong immunohistochemical expression of TTF-1 were statistically associated with well-differentiated phenotype (P=0.002), has inverse correlation with Ki-67 expression (P=0.01), and no correlation with age, sex, smoking history, and stages. The result from the Kaplan-Meier survival analysis showed that stages TTF-1 and Ki-67 were significantly associated with the prognosis of Xuanwei lung adenocarcinoma patients. The median progression-free survival in patients with I-II stages, strong positive expression TTF-1 and negative, and weak expressions Ki-67 groups was remarkably higher than those patients with III stage (46 months vs 32 months, P=0.001), negative and weak expressions TTF-1 (45 months vs 35 months, P=0.036) and strong positive expression Ki-67 groups (46 months vs 40 months, P=0.048), respectively. Conclusion Our results presented here suggest that TTF-1 may serve as a tumor suppressor gene based on its inverse correlation with Ki-67 proliferative activity. Patients with strong TTF-1 protein expression group tend to have a significantly better prognosis than patients with negative and weak TTF-1 protein expression group in Xuanwei lung adenocarcinoma