Evidence for a secretory pathway Ca2+-ATPase in sea urchin spermatozoa

AbstractPlasma membrane, sarco-endoplasmic reticulum and secretory pathway Ca2+-ATPases (designated PMCA, SERCA and SPCA) regulate intracellular Ca2+ in animal cells. The presence of PMCA, and the absence of SERCA, in sea urchin sperm is known. By using inhibitors of Ca2+-ATPases, we now show the presence of SPCA and Ca2+ store in sea urchin sperm, which refills by SPCA-type pumps. Immunofluorescence shows SPCA localizes to the mitochondrion. Ca2+ measurements reveal that ∼75% of Ca2+ extrusion is by Ca2+ ATPases and 25% by Na+ dependent Ca2+ exchanger/s. Bisphenol, a Ca2+ ATPase inhibitor, completely blocks the acrosome reaction, indicating the importance of Ca2+-ATPases in fertilization

Evoking agency: Attention model and behavior control in a robotic art installation

Robotic embodiments of artificial agents seem to reinstate a body-mind dualism as consequence of their technical implementation, but could this supposition be a misconception? The authors present their artistic, scientific and engineering work on a robotic installation, the Articulated Head, and its perception-action control system, the Thinking Head Attention Model and Behavioral System (THAMBS). The authors propose that agency emerges from the interplay of the robot’s behavior and the environment and that, in the system’s interaction with humans, it is to the same degree attributed to the robot as it is grounded in the robot’s actions: Agency cannot be instilled; it needs to be evoked

Investigation of the agricultural resources in Sri Lanka

The author has identified the following significant results. Several in-house capabilities were developed. The facilities to prepare color composites of excellent quality were developed, using bulk B/W 70 mm transparencies or 1:1,000,000 positive transparencies. These color composites were studied through optical devices on light tables. A zoom transfer scope was also added, enabling direct transfer of LANDSAT composite data on to base maps

Successful rehabilitation of species-rich heathlands after mining for heavy minerals

As human populations have been increasing, there has been a proportional increase in anthropogenic activities resulting in environmental degradation and destruction of the Earth‘s biota (Novacek and Cleland 2001). For many people, biological diversity has intrinsic value, and as a result of increased community awareness and legislative obligations, the field of restoration ecology has emerged. This discipline is defined by SER (2004) as "the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed". The ultimate goal is to restore a self-supporting ecosystem that is resilient to environmental perturbations without the need for further assistance (Urbanska et al. 1997; SER 2004) This report presents a study on shrubland restoration after heavy-mineral sand-mining near Eneabba, southwestern Australia. Four themes were highlighted in this report. First, restoration efforts were evaluated by comparing compositional, structural, and functional attributes between rehabilitated and surrounding natural analogues. Second, experimental fires were introduced to study sites to determine the vegetation‘s resilience to natural disturbances. Third, growth and reproductive capacities of common species were compared between rehabilitated and natural sites. Fourth, recommendations are given to facilitate the restoration of natural analogues, and to improve the overall persistence of the restored shrublands after fire

Assessing the impacts of COVID-19 pandemic on agricultural and food systems in Badulla District, Sri Lanka

Peer reviewedPublisher PD

Biochemical expression of exudes of a fungal-bacterial bio film during growth and maturation

Biofilms are often complex communities of multiple microbial species and remain attached to surfaces. Fungal-bacterial biofllms are formed when the fungal surface is colonized by one or more species of bacteria. These biofilms can enhance microbial effectiveness compared to the monocultures. Beneficial biofilms can be developed in vitro and be used for various agricultural and biotechnological purposes. As a recent development in biofertilizer research, fungal-rhizobial biofilms have been developed and these are termed biofilmed biofertilizers (BFBFs). This research was focused to investigate chemical composition of compounds exuded during growth and maturation of the biofilms. A developed fungal-bacterial biofilm using an Azotobacter species and a Colletorichum fungal species was used for the study. Exudates of the biofilm, fungal monoculture and bacterial monoculture in solid and liquid states were extracted separately by using three organic solvents; hexane, ethyl acetate and methanol. Extraction was done weekly for four weeks during growth and maturation of the biofllm. Then extracted exudates dissolved in organic solvents were evaporated by using a vortex evaporator. Thereafter crude was mixed with potassium bromide (KBr) and pellets were made. The KBr pellets were analyzed using Fourier Transform Infrared (FTIR) spectroscopy. To evaluate the effect of the exudates of the fungal-bacterial biofilm on seed germination and plant growth in comparison to bacterial and fungal monocultures, a plant assay was done weekly by using lettuce (Lactuca sativa) seeds (N 48). During all four harvests, the fungal-bacterial biofllm produced more diverse functional groups than the mono cultures. The developed biofilm produced carboxylic acids and carboxylic salts, which are associated with plant growth promoting hormones, especially in first and second harvests. Significantly higher plant height and high germination of lettuce with the biofilm exudates could be attributed to above fact. During third and fourth weeks, the biofllm produced more amines and amides than fungal and bacterial mono cultures. This may have contributed to increased pH in biofilm cultures compared to the mono cultures. Thus, it can be concluded that biochemical expression of exudates of fungal-bacterial biofilms during their growth and maturation is very useful for breaking dormancy of seeds and their germination and growth, contributing to high plant productivit

Continuous-flow synthesis of highly functionalized imidazo-oxadiazoles facilitated by microfluidic extraction

Abstract A versatile continuous-flow synthesis of highly functionalized 1,2,4-oxadiazoles starting from carboxylic acids is reported. This process was applied to the multistep synthesis of imidazo[1,2-a]pyridin-2-yl-1,2,4-oxadiazoles, using a three reactor, multistep continuous-flow system without isolation of intermediates. This continuous-flow method was successfully combined with a single-step liquid-liquid microextraction unit to remove high boiling point polar solvents and impurities and provides the target compounds in high purity with excellent overall yields. 23