Associative N2-fixation in plants growing in saline sodic soils and its relative quantification based on15N natural abundance

The interactive effect of low P supply (0, 10, 20 and 40 M) and plant age on nodule number, mass and functioning (ureide analysis technique), vegetative growth and pod production were investigated in glasshouse-grown nodulated cowpea (Vigna unguiculata L.cv. Kausband) in sand culture. Compared with 40 M P, P stress (0 M P) or very low (10 M P) supply markedly impaired nodulation, allantoin and amino-N concentrations and weight of N solutes in xylem exudates. Consequently, P stress reduced top growth and pod yields by 48 and 90%, respectively. N solutes in xylem exudates and total plant N assayed by Kjeldahl technique (as estimates of N₂ fixation) responded similarly to P supply. However, the relative ureide index [(ureide-N/ureide N+amino-N)×100] remained constant (99%), irrespective of P supply, indicating the plants' complete dependency on symbiosis for growth, without implying that growth was markedly increased by N₂ fixation. Although P concentrations in plant tops, roots and nodules increased with P supply, N concentrations in these plant tissues were unaffected by P supply. The concentrations of N and P in the nodules were 2–2 1/2 times higher than in plant tops. P application interacted strongly with plant age, with the largest P effect evidently achieved at the early podding stage. The significance and implications of these results are discussed.     

The effect of Cd2+ on the biosynthesis of chlorophyll in leaves of barley

The effect of cadmium on the biosynthesis of chlorophyll has been investigated in the leaves of dark-grown seedlings of barley ( Hordeum vulture L. cv. Proctor). Cd2+ inhibited the production of chlorophyll by affecting 1) the synthesis of 5-aminolacvulinic acid and 2) the protoehlorophyllide reductase ternary complex with its substrates. Cd2+ had no effect on the constituent enzymes that catalyse the synthesis of free protoehlorophyllide from 5-aminolaevulinic acid. The results obtained are consistent with Cd2+ inhibiting the formation of chlorophyll by reacting with essential thiol groups in both the protochlorophyllide reductase protein and the enzyme(s) involved in the light dependent synthesis of 5-aminolaevulinic acid.     

Chlorobium limicola forma thiosulfatophilum: Biocatalyst in the Production of Sulfur and Organic Carbon from a Gas Stream Containing H2S and CO2

Chlorobium limicola forma thiosulfatophilum (ATCC 17092) was grown in a 1-liter continuously stirred tank reactor (800-ml liquid volume) at pH 6.8, 30°C, saturated light intensity, and a gas flow rate of 23.6 ml/min from a gas cylinder blend consisting of 3.9 mol% H₂S, 9.2 mol% CO₂, 86.4 mol% N₂, and 0.5 mol% H₂. This is the first demonstration of photoautotrophic growth of a Chlorobium sp. on a continuous inorganic gas feed. A significant potential exists for applying this photoautotrophic process to desulfurization and CO₂ fixation of gases containing acidic components (H₂S and CO₂).     

Three research priorities for just and sustainable urban systems: Now is the time to refocus

Now is the time to refocus efforts in urban research and design. A changing climate and extreme weather events are presenting unique challenges to urban systems around the world. These challenges illuminate the social barriers that accompany disruptive events such as resource inequities and injustices. In this perspective, we provide three research priorities for just and sustainable urban systems that help to address these matters. The three research priorities are: (1) social equity and justice, (2) circularity, and (3) digital twins. Conceptual context and future research directions are provided for each. For social equity and justice, the future directions are mandatory equity analysis and inclusionary practices, understanding and reconciling historical injustices, and intentional integration with diverse community stakeholders. For circularity applications, they are better metrics for integration, more robust evaluation frameworks, and dynamic modeling at multiple spatial and temporal scales. Future directions for digital twins include developing principles to reduce complexity, integrating model and system components, and reducing barriers to data access. These research priorities are core to meeting several of the United Nations Sustainable Development Goals (i.e., 1—No Poverty, 8—Decent Work and Economic Growth, 10—Reduced Inequalities, and 11—Sustainable Cities and Communities). Useful social and technical matters are discussed throughout, where we highlight the importance of prioritizing localized research efforts, provide guidance for community-engaged research and co-development practices, and explain how these priorities interact to align with the evolving field of industrial ecology.     

Culture Independent Diversity of Bacterial Communities Indigenous to Lower Altitude at Laohugou Glacial Environment

Abstract

High-throughput sequencing approach of the 16S rRNA gene was employed to evaluate the bacterial diversity inhabit in melted water, snow, soil, and rocks samples at the lower altitudes of the Laohugou glacial environment. Bioinformatics tools were used to process millions of Illumina reads for alpha and beta diversities of bacterial communities. The diversity indices such as Chao, Shannon, and Simpson were different in the collected samples and solid samples (soil and rocks) showed higher taxon richness and evenness. Taxonomic diversity was unexpectedly higher and the major portion of sequences was assigned to Proteobacteria, Actinobacteria, and Acidobacteria. Higher variation in community structure was reported at the class level and Alphaproteobacteria was dominant. The solid niches were occupied by a higher number of phyla compared with liquid. The physicochemical variables acted as spatial gradients and associated with the bacterial structural communities of the glacial ecosystem. Findings showed that both Proteobacteria and Actinobacteria in solid samples influenced the bacterial community structure in downstream liquid samples. Interestingly, the metagenomic biomarkers were higher in liquid samples. This study provides precious datasets to understand the bacterial community in a better way under the influence of spatial, physical and environmental factors.     

Cold atmospheric plasma induced genotoxicity and cytotoxicity in esophageal cancer cells

Molecular Biology Reports - In this paper, we studied the functional effects of cold atmospheric plasma (CAP) on the esophageal cancer cell line (KYSE-30) by direct and indirect treatment and...     

The Arabidopsis expansin gene (AtEXPA18) is capable to ameliorate drought stress tolerance in transgenic tobacco plants

Molecular Biology Reports - Expansins are cell wall proteins loosening plant cell in pH-dependent manner. This study aimed to investigate the role of AtEXPA18 in different morphological,...     

Growth and Physiology of Maize (Zea mays L.) in a Nickel-Contaminated Soil and Phytoremediation Efficiency Using EDTA

Journal of Plant Growth Regulation - Nickel (Ni) element is strongly phytotoxic at high concentrations for several plants, but due to its dual behavior and complicated chemistry, it has received...