Biogenic Synthesis of Silver Nanoparticles, Characterization and Their Applications—A Review

With the growing awareness for the need of sustainable environment, the importance of synthesizing and the application of green nanoparticles has gained special focus. Among various metal nanoparticles, silver nanoparticles (AgNPs) have gain significant attention. AgNPs are synthesized conventionally by physical and chemical methods using chemicals such as reducing agents, which are hazardous to environment due to their toxic properties, provoking a serious concern to create and develop environment friendly methods. Thus, biological alternatives are emerging to fill gaps, such as green syntheses that use biological molecules taken from plant sources in the form of extracts, which have shown to be superior to chemical and physical approaches. These biological molecules derived from plants are assembled in a highly regulated manner to make them suitable for metal nanoparticle synthesis. The current review outlines the wide plant diversity that may be used to prepare a rapid and single-step procedure with a green path over the traditional ones, as well as their antifungal activity.

Experimental investigation of bending characteristics of hybrid composites fabricated by hand layup method

The extensive applications of hybrid composite materials in the field of transportation and structural domine provide prominent advantages in the order of stiffness, strength even cost. However extend the advantages of hybrid campsites in several field such as aviation and marine even more additional properties should be inculcate in them. During production of such profitable composites poses some problems at time at decompose and processing. It’s better to develop environment friendly and reusable composites, bio hybrid composite materials such of the one. In this paper, focused on development of Eco-friendly hybrid bio composites with the ingredients of drumstick fibers, glass fiber along with polyester resin. This hybrid bio composites subjected to bending test and evaluate the characteristics of bending properties, this research evident that bending characteristics of hybrid composites with longitudinal fiber orientation better than transverse.

Potential Role of Rice Plant Growth Promoting Phylloplane and Rhizospheric Bacteria in Controlling Xanthomonas oryzae pv. oryzae

Rice is an important cereal worldwide and it occupies the top position among the cereals in Bangladesh. Rice plant suffers from around 32 diseases of which ten are major in Bangladesh at present. Among the diseases, Bacterial Blight (BB) caused by X. oryzae pv. oryzae (Xoo) considered as a most destructive disease occurs in both rainfed and irrigated seasons of Bangladesh. BB causes considerable yield loss varies from 30 to 50% depending on the outbreak. It is also an important disease in most of the South and Southeast Asian countries. To develop environment-friendly sustainable management approach against BB of rice, in total sixty three plant growth promoting bacteria were identified from rice phylloplane and rhizosphere that are antagonistic to X. oryzae pv. oryzae during boro and aman seasons 2018 and 2019.These bacterial species inhibited the growth of X. oryzae pv. oryzae in vitro by 20.83 to 76.19%. These bacterial isolates were identified by sequencing of PCR products of 16SrDNA belonging to the genera mostly Pseudomonas, Bacillus and Serratia. Out of these bacterial species, 48 bacterial species were found as positive for IAA production, all 63 bacterial species were found positive for siderophore production and 48 were found capable to solubilize insoluble phosphate. Based on growth inhibition of X. oryzae pv. oryzae in in vitro, thirty two bacterial species were selected for plant growth promotion assessment and evaluation of net house and field efficacy in controlling BB of rice. These bacterial species were formulated using talcum powder which was viable for at least three months post formulation. Assessment of plant growth promoting determinants revealed that all 32 bacterial species identified in this study enhance the growth of rice plants as measured by root and shoot length and and reduced the BB severity in susceptible rice cultivar significantly as compared with untreated control.

The Linkage of Indonesian Language Learning with the Environment

Environmental materials are very important to be applied in Indonesian language learning. Environmental materials support students in understanding Indonesian language material well, can broaden students 'insight, and can build students' ecological intelligence. The environment is a component that is closely related to everyday life. Therefore, to be able to develop environment-based learning teacher can easily search for real-life examples that make students more familiar will the material provided, so as to assist teachers in the material implies Indonesian in schools.

ExoNet Database: Wearable Camera Images of Human Locomotion Environments

Advances in computer vision and artificial intelligence are allowing researchers to develop environment recognition systems for powered lower-limb exoskeletons and prostheses. However, small-scale and private training datasets have impeded the widespread development and dissemination of image classification algorithms for classifying human walking environments. To address these limitations, we developed ExoNet - the first open-source, large-scale hierarchical database of high-resolution wearable camera images of human locomotion environments. Unparalleled in scale and diversity, ExoNet contains over 5.6 million RGB images of different indoor and outdoor real-world walking environments, which were collected using a lightweight wearable camera system throughout the summer, fall, and winter seasons. Approximately 923,000 images in ExoNet were human-annotated using a 12-class hierarchical labelling architecture. Available publicly through IEEE DataPort, ExoNet offers an unprecedented communal platform to train, develop, and compare next-generation image classification algorithms for human locomotion environment recognition. Besides the control of powered lower-limb exoskeletons and prostheses, applications of ExoNet could extend to humanoids and autonomous legged robots.

Performance Comparison of Stabilised Soils Based On their Liquefaction Resistances – A Review

The behavior of sands under undrained monotonic and cyclic loading are a widely discussed topic in fields of geotechnical engineering. The strength of cohesion less soils get drastically reduced under sudden undrained loading, especially if they are in saturated or submerged state, making them more prone to liquefaction. Researchers have conducted experiments on soils treated with a wide variety of chemicals, fibres,waste products and biopolymers to find out the liquefaction resistance of the modified sands. Among these additives, use of chemicals like cement pose major environmental problems like carbon dioxide emission and production of air pollutants like SO2, NO2, VOCs and other particulate matter. Plastic wastes such as PET bottles and plastic bags and byproducts like flyash and granulated blast furnace slag are used from past due to their strength enhancing properties. Plastic require thousands of years for their breakdown. The leachate generated by flyash and slag are slightly acidic in nature, polluting surface waters. In order to develop environment friendly construction practices, biopolymers like agar, starch, guar gel and xanthan gum are included recently in soil stabilization techniques. Being, renewable, reusable and carbon neutral, there is an increased interest on these biopolymers. This study is aimed at comparing the liquefaction resistances of modified and unmodified sands with a variety of additives based on results of Triaxial tests.

The Effect of Mechanical Stress on Plant Susceptibility to Pests: A Mini Opinion Review

Plants are subject to multiple pest attacks during their growing cycle. In order to address consumers’ desire to buy healthy vegetables and fruits, i.e., without chemical residues, and to develop environment-friendly agriculture, major research efforts are being made to find alternative methods to reduce or suppress the use of chemicals. Many methods are currently being tested. Among these methods, some are being tested in order to modify plant physiology to render it less susceptible to pathogen and pest attacks by developing plant immunity. An emerging potentially interesting method that is being studied at this time is mechanical stimuli (MS). Although the number of articles on the effect of MS on plant immunity is still not large, it has been reported that several types of mechanical stimuli induce a reduction of plant susceptibility to pests for different plant species in the case of wounding and non-wounding stimuli. This mini review aims to summarize the knowledge available at this time by raising questions that should be addressed before considering MS as an operable alternative method to increase plant immunity for crop protection.

Microorganisms as bioinsecticides; short review

Hundred thousand tons of chemical insecticides are used annually in Nigeria to combat insect disease vectors especially agricultural pests, but this sort of vector control method is gradually being substituted due to their environmental effects on non-target beneficial insects especially vertebrates through contamination of food and water. To counteract this contamination, attention, efforts and researches were directed to the use of biological control agents including insect pathogens. As a result, the use of bio insecticide, as a component of integrated pest management (IPM), has been gaining acceptance over the world. Microbial pathogens comprise of organisms which cause disease, these organisms are disseminated in the pest population in large quantity in a manner similar to application of chemical pesticides. Insects like other organisms are susceptible to a variety of diseases caused by different groups of microorganisms including virus, bacteria, fungi, protozoa and nematodes. Microbial pathogens of insects are intensively investigated to develop environment friendly pest management strategies in agriculture. Microbial insecticides represent today the best alternative to chemical insecticides in controlling insect pests, they are safe for non-target species and human health are believed to show low persistence in the environment. This short review indicates that microbial insecticides are the safe alternative way possessing all the requirements to replace chemical insecticides hence, they can be utilized in pest management and control. Keywords: Bio-insecticides, Microorganisms, biological control, pest, chemical insecticides

Assessing environmental fragility in a mining areafor specific spatial planning purposes

Environmental fragility in a mining area is evaluated both in terms of its biophysical (natural) and socio-economic components and their anthropogenic interactions. We identified multiple criteria and indicators for this task, but then reduced these according to responses given by 60 experts in domains related to spatial planning. We used the selected criteria and indicators to develop environment fragility indices for each territorial administrative unit (LAU2) in Gorj County in south-western Romania. The resulting indices reveal quite large spatial variations in fragility and evidence that highly fragile human and physical environments are to some extent intertwined. In this respect, such environmental components as climate, soils, ecosystems, natural hazards and economic issues provide constraints on human activities, whilst humans themselves can, without sufficient care, increase fragility and adversely affect the quality of living environments for present and future generations. We also explore how such estimates of natural and anthropogenic fragility might enable better specific planning for local and regional development that aims to ameliorate both environmental and human adversity in an integrated way.