This study investigates whether gender diversity on the board of directors in the United States is associated with firms' environmental performance. Under the theoretical framework of resource ...dependence theory, we argue that gender diversity brings a greater variety of skills to the board. Diversity allows for a healthy mix of knowledge and experience to improve the decision‐making process of the board. Using propensity score matching and controlling for endogeneity, this study uses a more rigorous statistical model than previous work. It also uses content analysis of directors' biographies to provide evidence of the role that gender diversity plays. We find gender diversity is positively associated with firms' environmental performance scores primarily in the more environmentally impacting industries. Therefore, our research provides valuable direction for those firms working to improve both their boards' gender diversity and their environmental performance. Our findings also offer insight into the mixed results of previous studies.
The ecological footprint and economic performance of the current suite of biofuel production methods make them insufficient to displace fossil fuels and reduce their impact on the inventory of Green ...House Gas (GHG) in the global atmosphere. Algae metabolic engineering forms the basis for 4th generation biofuel production which can meet this need. The first generation biofuels are known to be made from agricultural products such as corn or sugarcane. The second generation biofuels use all forms of (lingo)cellulosic biomass. The third and fourth generation of biofuel production involves "algae-to-biofuels" technology: the former is basically processing of algae biomass for biofuel production, while the latter is about metabolic engineering of algae for producing biofuels from oxygenic photosynthetic microorganisms. Our review focuses on the research achievement of metabolic engineering of algae for biofuel production. It is concluded that 4th generation biofuel production has introduced the "cell factory" concept in this field, and shifted the research paradigm. There still exists several technical bottlenecks in algae biofuel research and development, which can only be solved by the use of post-genome tools on these photosynthetic organisms.
The k-Nearest Neighbor algorithm(kNN) is an algorithm that is very simple to understand for classification or regression. It is also a lazy algorithm that does not use the training data points to do ...any generalization, in other words, it keeps all the training data during the testing phase. Thus, the population size becomes a major concern for kNN, since large population size may result in slow execution speed and large memory requirements. To solve this problem, many efforts have been devoted, but mainly focused on kNN classification. And now we propose an algorithm to decrease the size of the training set for kNN regression(DISKR). In this algorithm, we firstly remove the outlier instances that impact the performance of regressor, and then sorts the left instances by the difference on output among instances and their nearest neighbors. Finally, the left instances with little contribution measured by the training error are successively deleted following the rule. The proposed algorithm is compared with five state-of-the-art algorithms on 19 datasets, and experiment results show it could get the similar prediction ability but have the lowest instance storage ratio.
Atherosclerosis is a progressive, chronic inflammation in arterial walls. Long noncoding RNAs (lncRNAs) participate in inflammation, but the exact mechanism in atherosclerosis is unclear. Our ...microarray analyses revealed that the levels of lncRNA-FA2H-2 were significantly decreased by oxidized low-density lipoprotein (OX-LDL). Bioinformatics analyses indicated that mixed lineage kinase domain-like protein (MLKL) might be regulated by lncRNA-FA2H-2. In vitro experiments showed that lncRNA-FA2H-2 interacted with the promoter of the MLKL gene, downregulated MLKL expression, and the binding sites between -750 and 471 were necessary for lncRNA-FA2H-2 responsiveness to MLKL. Silencing lncRNA-FA2H-2 and overexpression of MLKL could activate inflammation and inhibited autophagy flux. Both lncRNA-FA2H-2 knockdown and overexpression of MLKL could significantly aggravate inflammatory responses induced by OX-LDL. We found that the 3-methyladenine (3-MA) and Atg7-shRNA enhanced inflammatory responses induced by knockdown of lncRNA-FA2H-2 and overexpression of MLKL. We demonstrated that the effects of MLKL on autophagy might be associated with a mechanistic target of rapamycin (mTOR)-dependent signaling pathways. In vivo experiments with apoE knockout mice fed a western diet demonstrated that LncRNA-FA2H-2 knockdown decreased microtubule-associated expression of microtubule-associated protein 1 light chain 3 II and lysosome-associated membrane protein 1, but increased expression of sequestosome 1 (p62), MLKL, vascular cell adhesion molecule-1, monocyte chemoattractant protein-1, and interleukin-6 in atherosclerotic lesions. Our findings indicated that the lncRNA-FA2H-2-MLKL pathway is essential for regulation of autophagy and inflammation, and suggested that lncRNA-FA2H-2 and MLKL could act as potential therapeutic targets to ameliorate atherosclerosis-related diseases.
Belowground life relies on plant litter, while its linkage to living roots had long been understudied, and remains unknown in the tropics. Here, we analysed the response of 30 soil animal groups to ...root trenching and litter removal in rainforest and plantations in Sumatra, and found that roots are similarly important to soil fauna as litter. Trenching effects were stronger in soil than in litter, with an overall decrease in animal abundance in rainforest by 42% and in plantations by 30%. Litter removal little affected animals in soil, but decreased the total abundance by 60% in rainforest and rubber plantations but not in oil palm plantations. Litter and root effects on animal group abundances were explained by body size or vertical distribution. Our study quantifies principle carbon pathways in soil food webs under tropical land use, providing the basis for mechanistic modelling and ecosystem‐friendly management of tropical soils.
Our study quantifies the importance of litter vs. living root resources for soil animals across 30 taxonomic groups after conversion of rainforest into monoculture plantations. The results suggest that roots are of similar importance to litter for the soil animal food web, with root trenching effects being stronger in soil than in litter and litter removal little affecting animals in soil. Litter and root effects on animal abundances were related to animal body size or vertical distribution in soil and thus shape soil animal communities by different mechanisms.
Colorectal cancer (CRC) is the second common cause of cancer-related human mortalities. Dysregulation of histone 3 (H3) methylation could lead to transcriptional activation of multiple oncogenes, ...which is closely associated with CRC tumorigenesis and progression. Nuclear receptor-binding SET Domain protein 2 (NSD2) is a key histone methyltransferase catalyzing histone H3 lysine 36 dimethylation (H3K36me2). Its expression, the potential functions, and molecular mechanisms in CRC are studied here. Gene Expression Profiling Interactive Analysis (GEPIA) bioinformatics results showed that the NSD2 mRNA expression is elevated in both colon cancers and rectal cancers. Furthermore, NSD2 mRNA and protein expression levels in local colon cancer tissues are significantly higher than those in matched surrounding normal tissues. In primary human colon cancer cells and established CRC cell lines, shRNA-induced silencing or CRISPR/Cas9-induced knockout of NSD2 inhibited cell viability, proliferation, cell cycle progression, migration, and invasion. Furthermore, NSD2 shRNA or knockout induced mitochondrial depolarization, DNA damage, and apoptosis in the primary and established CRC cells. Contrarily, ectopic NSD2 overexpression in primary colon cancer cells further enhanced cell proliferation, migration, and invasion. H3K36me2, expressions of multiple oncogenes (ADAM9, EGFR, Sox2, Bcl-2, SYK, and MET) and Akt activation were significantly decreased after NSD2 silencing or knockout in primary colon cancer cells. Their levels were however increased after ectopic NSD2 overexpression. A catalytic inactive NSD2 (Y1179A) also inhibited H3K36me2, multiple oncogenes expression, and Akt activation, as well as cell proliferation and migration in primary colon cancer cells. In vivo, intratumoral injection of adeno-associated virus (AAV)-packed NSD2 shRNA largely inhibited primary colon cancer cell xenograft growth in nude mice. Together, NSD2 exerted oncogenic functions in CRC and could be a promising therapeutic target.
The mechanisms and chemo- and regioselectivities of Ru(II)-catalyzed decarboxylative C–H alkenylation of aryl carboxylic acids with alkynes were investigated with density functional theory (DFT) ...calculations. The catalytic cycle involves sequential carboxylate-directed C–H activation, alkyne insertion, decarboxylation and protonation. The facile tether-assisted decarboxylation step directs the intermediate toward the desired decarboxylative alkenylation, instead of typical annulation and double alkenylation pathways. The decarboxylation barrier is very sensitive to the tether length, and only the seven-membered ring intermediate can selectively undergo the designed decarboxylation, suggesting a tether-dependent chemoselectivity. This tether-dependent chemoselectivity also applies to the alkyl tethers. In addition, the polarity of solvent is found to control the chemoselectivity between the decarboxylative alkenylation and 4 + 2 annulation. Solvent with low polarity (toluene) favors the decarboxylation pathway, leading to the decarboxylative alkenylation. Solvent with high polarity (methanol) favors the ionic stepwise C–O reductive elimination pathway, leading to the 4 + 2 annulation. To understand the origins of regioselectivity with asymmetric alkynes, the distortion/interaction analysis was applied to the alkyne insertion transition states, and led to a predictive frontier molecular orbital model. The asymmetric alkynes selectively use the terminal with the larger HOMO orbital coefficient to form the C–C bond in the insertion step.
In December 2019, coronavirus disease 2019 (COVID-19), which is caused by the new coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was identified in Wuhan (Hubei province, ...China)
; it soon spread across the world. In this ongoing pandemic, public health concerns and the urgent need for effective therapeutic measures require a deep understanding of the epidemiology, transmissibility and pathogenesis of COVID-19. Here we analysed clinical, molecular and immunological data from 326 patients with confirmed SARS-CoV-2 infection in Shanghai. The genomic sequences of SARS-CoV-2, assembled from 112 high-quality samples together with sequences in the Global Initiative on Sharing All Influenza Data (GISAID) dataset, showed a stable evolution and suggested that there were two major lineages with differential exposure history during the early phase of the outbreak in Wuhan. Nevertheless, they exhibited similar virulence and clinical outcomes. Lymphocytopenia, especially reduced CD4
and CD8
T cell counts upon hospital admission, was predictive of disease progression. High levels of interleukin (IL)-6 and IL-8 during treatment were observed in patients with severe or critical disease and correlated with decreased lymphocyte count. The determinants of disease severity seemed to stem mostly from host factors such as age and lymphocytopenia (and its associated cytokine storm), whereas viral genetic variation did not significantly affect outcomes.
Tree - soil interactions depend on environmental conditions. Planting trees may affect soil microbial communities and compromise their functioning, particularly in unfavorable environments. To ...understand the effects of tree species composition on soil microbial communities, we quantified structural and functional responses of soil microorganisms to tree species planted in various environments using substrate-induced respiration and phospholipid fatty acid analyses. Five forest types were studied including pure stands of native European beech (Fagus sylvatica), range expanding Norway spruce (Picea abies), and non-native Douglas-fir (Pseudotsuga menziesii), as well as the two conifer - beech mixtures. We found that microbial functioning depends strongly on soil nutrient concentrations in the studied forest sites. At nutrient-poor sites, soil microorganisms were more stressed in pure and mixed coniferous forests, especially in Douglas-fir, compared to beech forests. By contrast, microbial structure and functional indicators in beech forests varied little with site conditions, likely because beech provided ample amounts of root-derived resources for microbial growth. Since soil microbial communities are sensitive to Douglas-fir, planting Douglas-fir may compromise ecosystem functioning, especially at nutrient-poor sites. Overall, root-derived resources are important for determining the structure and functioning of soil microbial communities, so soil microbial responses to tree species will depend upon the provisioning of these resources as well as site-specific environmental conditions.
•Soil microorganisms do not respond to forest types at nutrient-rich sites.•European beech mitigates microbial stress in nutrient-poor forest soils.•Microbial stress in nutrient-poor forest soils is intensified by planting Douglas-fir.•Admixing conifers to beech compromises microbial functioning at nutrient-poor sites.
Background
MicroRNAs (miRNAs) have become increasingly prevalent as a result of the association of their deregulation with neurodegenerative disorders, especially Alzheimer's disease (AD). However, ...the association between miRNAs and AD remains unclear.
Methods
In the present study, Nine representative miRNA datasets were selected for the identification of the critical miRNAs by analyzing the overlapping relationships among them. TargetScan software (http://www.targetscan.org) was used to predict the target genes of these miRNAs. In addition, the Database for Annotation Visualization and Integrated Discovery (DAVID; http://david.abcc.ncifcrf.gov) and TfactS (http://www.tfacts.org) datasets were used for combined analysis of functional enrichment and transcription factor (TF) analysis.
Results
Thirteen key miRNAs were identified, of which four were significantly up‐regulated (hsa‐miR‐101,hsa‐miR‐155, has‐miR‐34a, has‐miR‐9) and eight were found to be significantly down‐regulated (hsa‐let‐7d‐5p, hsa‐let‐7 g‐5p, hsa‐miR‐15b, has‐miR‐191‐5p, hsa‐miR‐125b, has‐miR‐26b‐5p, hsa‐miR‐29b, hsa‐miR‐342‐3p). The functional enrichment analysis indicated that up‐regulated signature miRNA targets were associated with transcription from the RNA polymerase II promoter process and the chemical synaptic transmission process. Down‐regulated signature miRNA targets were mostly enriched with respect to positive regulation of transcription from the RNA polymerase II promoter process, p53 signaling, and microRNAs in cancer pathways. TF analysis showed that 87 TFs were influenced by the up‐regulated miRNAs, and 134 TFs were influenced by the down‐regulated miRNAs. In total, 70 (45.5%) TFs were affected by both up‐regulated and down‐regulated miRNAs.
Conclusions
In summary, 13 key miRNAs were found to have a vital function in the pathological progress of AD, as well as the target genes and TFs of these miRNAs. The potential functions of these miRNAs as diagnostic and therapeutic targets of the AD are revealed by the present study.
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