Recent Research Advances in Biology Vol. 6

The study was conducted in 2018, on the Chrysichthys auratus in the Volta Lake, due to its socio-economic importance to the many and varied dependent fishermen, fish processors and fish traders. As they are abundant, they are exploited so well they have been included in the 2010 International Union for Conservation of Nature’s (ICUN) Red list of threatened species. The objective was to determine the reproductive strategy to facilitate sustainable management of the fish stocks. A total of 452 fish samples collected on monthly basis were measured, weighed and dissected for determination of, sexual maturity, sex ratio, gonadosomatic index GSI, hepasomatic index HSI, condition factor k, visceral fat index VFI and monthly stomach fullness in relation to sexual maturity. According to the length at first maturity determined, 89% of the female fish caught, fell below that critical length, suggesting growth overfishing, attributed to size and sex selective tendencies of bamboo pipe fishing. During gonad development, the correlation of the GSI to the HSI and the VFI was inverse and insignificant but in the post gonad development phase it switched to a positive and insignificant relationship. The point of switch, in September, was synonymous with spawning and indicative of the spawning period. However, the point of switch, of the inverse and significant correlation, to a positive and insignificant relationship, early in post gonad development, synonymous with spawning, is indicative of the major spawning period and necessary to be monitored for sustainable management of the fishery by resource managers and researchers. It was concluded that the reproductive strategy was to time the spawning process, in September, to coincide with the upwelling phenomenon (June – September), associated with fish food abundance, thereby enhancing the survival of the offspring. A seasonal ban on fishing and a total ban on bamboo pipe fishing were recommended.

The study was conducted at ten fishing sites, in Stratum VII of the Volta Lake, comparing the technical and economic performances of gillnet types with different as against the usual same, hanging ratios at the top and down ropes, with a standard gillnet of hanging ratio 0.5 at the top and down ropes. The shape of a mesh size is controlled by the hanging ratio and is one of the most important factors affecting yield and selectivity of gillnets. The objective was to determine whether gillnet types with different hanging ratios at the top and down ropes could be superior in enhancement of the performance of monofilament gillnets over the usual gillnet types with same hanging ratios at the top and down ropes, by determining principally the; fishing efficiency, cost efficiency and the index of economic efficiency of the net types, under the same fishing conditions. In April – June 2016, the depth of the fishing sites, the quantity and value of fish caught, and the costs of the fishing operations were determined; and in February 2017, the length frequency distribution of Oreochromis niloticus and Sarotherodon galileus, caught by the net types was recorded for differences. The results showed that the gillnet types with different hanging ratios at the top and down ropes, recorded superior efficiencies over the gillnet types with same hanging ratios. It was concluded that different hanging ratios, at the top and down ropes, combined with slack netting constituted a superior intervention for enhancing technical and economic efficiencies of monofilament gillnets. The insignificant difference in the LFD of the Tilapiine species caught could be attributed to the absence of hard spines favoring capture by gilling by all the net types, over entangling, a property of only slack nets which could result in difference in the sizes of fish caught.

First-principles simulations start to be applicable to the photochemistry and photophysics in biological systems. In this review the prerequisites for investigating such excited state phenomena in large systems are outlined. Generally, a quantum mechanical description of the electronic structure is combined with molecular dynamics simulations, which allows to describe the motion of the atoms in the field produced by the quantum-mechanical potential. Like this, bonds can be formed and broken, that is, chemical reactions can be simulated. The review focuses on applications of first-principles molecular dynamics to photoactive proteins.

Whitefly, Bemisia tabaci (Gennadius), a common insect feeding on plants, belongs to the family Aleyrodidae of the order Homoptera. The quantity of food source especially brinjal, is one of the major factors that has attracted whitefly in the studied area. In fact, the flight ability of whitefly enables them to search for food quickly. Thus could encourage whitefly to reproduce in great numbers and subsequently cause severe infestation in the fields. Many farmers are not interested to grow brinjal after they have gone through some bad experience due to some whitefly infestations, which have resulted in a total crop loss of brinjal fruits. At present, information on the population dynamics of whiteflies locally on brinjal is still lacking. Therefore, this study determined the population of immature whitefly and the population was sampled and predicted precisely via spatial distribution on brinjal plant before intervention program can be made. The study was conducted at the Field Laboratory of the Faculty of Applied Science, Universiti Teknologi MARA, Shah Alam, Selangor, Malaysia. The study on the population of whitefly larvae on brinjal plants covered all the plant strata except for the upper stratum. The populations of whitefly were aggregated (Taylor’s Power Law Calculate) in first and second cropping of brinjal plants.  Generally, the populations of whitefly were aggregated significantly for both seasons particularly in the middle strata of brinjal plants. It can be concluded that the total number of whitefly larvae were found to be most abundant and can be predicted precisely in the middle stratum of the brinjal plants. Henceforth, these studies are indeed appropriate to generate a comprehensive understanding on the insect population, which could support an effective pest management programme and crop improvement strategy.

The article is devoted to the specific consideration of the cochlear transduction for the low level sound intensities, which correspond to the regions near the perception threshold. The basic cochlea mechanics is extended by the new concept of the molecular filters, which allows discussing the transduction mechanism on the molecular level in the space?time domain. The molecular filters are supposed to be built on the set of the stereocilia of every inner hair cell. It is hypothesized that the molecular filters are the sensors in the feedback loop, which includes also outer hair cells along with the tectorial membrane and uses the zero compensation method to evaluate the traveling wave shape on the basilar membrane. Besides the compensation, the feedback loop, being spatially distributed along the cochlea, takes control over the tectorial membrane strain field generated by the outer hair cells, and implements it as the mechanism for the automatic gain control in the sound transduction. The numerical simulations of the traveling waves for the real sound intensities also    confirm the low values of the basilar membrane deformations.

Considered is the model of the transversal utricle membrane deflections evoked by the linear accelerations. The basic idea underlying this consideration is that the linear accelerations can cause both longitudinal and transversal deformations when acting along the membrane in the buckling way. The real 3  utricle membrane structure was simplified by considering its middle section and evaluating its elastic properties in  space. The steady state transversal deflections along the membrane are analytically evaluated and numerically simulated using the  elasticity theory. The transversal deflections are found to be more expressive and stronger as compared to the conventional longitudinal deformations. The maxima of longitudinal deformations and transversal deflections are observable in different regions of the utricle membrane. The revealed properties could be used for explanation of the transduction processes in the otolith organ. Based on the implemented modeling approach the new otolithic membrane mechanical properties are discussed and new explanations for the available experimental data are given. The otolithic membranes of utricle and sacculus are approximately orthogonal in space, what helps them decomposing the arbitrary linear accelerations into projections of the body reference systems.

The life cycle of tree frogs (Hyla savygnyi) in various localities and habitats in northern Israel in the Upper Galilee and Golan Heights (annual rainfall range of 500–1000 mm) and the Hula Valley, ranging from 212 to 740 m above sea level, was studied. Tree frogs were observed around winter rain pools, springs and streams. Fifty-one different breeding sites were monitored. The frogs forage on land. During the breeding season, adults forage periodically on the shore and on high plant stems above the water surface. Only ponds and springs with stable, non-flowing water are used by tree frogs for reproduction and this is where the larvae can metamorphose. The male call at the breeding site attracts the female, who then comes to the male, and breeding occurs underwater. Breeding time in Israel varies according to location and geographical and ecological conditions. It takes place in March–April in northern Israel, the Upper Galilee, the Golan Heights and the Hula Valley. In various breeding sites, larvae grow between April and June. Apparently, tree frog larvae adapt to breeding sites where stable water is found, such as in ponds or springs, but not to breeding sites with flowing water such as streams or rivers. Various anuran and Urodela larvae were found in the same breeding sites as the larvae of H. savygnyi, including Pseudepidalea viridis, Rana bedriagae, Pelobates syriacus, Salamandra infraimmaculata and Triturus vittatus. Following metamorphosis, H. savygnyi adapts to terrestrial life in semi-arid habitats, and is found on plants or in hiding places under rocks and in holes to prevent dehydration, particularly during hot and dry weather. The ability to change color helps the frogs hide in various substrates. The rate of water loss for terrestrial H. savygnyi during dehydration is around 50% of body weight. Plasma osmolality increases from 200 mOsm/kg to about 450 mOsm/kg, which helps the tree frog survive in semi-arid habitats.

Brain water metabolism is directly involved in the processes of cellular communication, transit of the signaling molecules, neurotransmitters, cytokines and substrates, participates in the clearance of pathogenic metabolites, etc. Many serious neurological conditions arise from the altered flow of the brain fluids (e.g. Alzheimer’s disease, idiopathic normal pressure hydrocephalus, migraine, traumatic brain injury and stroke, brain edema, etc.). At present, the orthodox theory fails to explain the accumulated experimental evidence and clinical data on the brain water metabolism. Modeling becomes an important approach to testing current theories and developing new realistic mechanisms.

A novel computational model of brain water metabolism has been developed and explored. Based on an interdisciplinary approach, the brain interstitial space is viewed as a nanofluidic domain where fluid flow is governed by the slip-flow principles of nanofluidics. Aquaporin-4 (AQP4) of the astrocyte endfeet membranes ensures kinetic control over water movement across the blood-brain barrier. The pulsatory intracranial pressure presents the driving force behind the transcapillary water flow. The model demonstrates good predictability in respect to some physiological features of the brain water metabolism and relevance in explaining some clinical conditions. The model may find its use in neurobiological research, development of the AQP4-targeted drug therapy, optimization of the intrathecal drug delivery to the brain tumours and in a research on a broad spectrum of water-metabolic-disorder-related conditions.

Health care waste at the National Hospital of Sri Lanka (NHSL) consists of infectious, hazardous as well as non-hazardous waste generated at various places within the institution. Health care waste management function in the NHSL is outsourced to a private company. Waste Management needs due attention and if the procedure did not follow the safe methods definitely create a great problem to the patients, staff as well as the public and the environment. The segregation of waste at the selected units was satisfactory. All (100%) units had a sharp bin to separately collect needles and other sharp materials. They used color code in waste bins. Occupational safety measures take during handling waste were not satisfactory. None of them were found wearing protective gloves, masks or boots. Even though the wards practice segregation of waste according to the color code, the transportation of waste from wards to the disposal area was unhealthy and not up to the standards. This was mainly due to the carelessness of the staff, supervisors and the cleaning service workers. The knowledge on safe handling and transporting waste among waste handlers were not adequate thus they deserves for training on healthcare waste management.

Aims: To evaluate the effect of aqueous extract of unripe fruit of Musa sapientum Linn in combination with Vitamin C on aspirin and ethanol induced ulcer models in Wistar rats. It is a tropical plant whose fruit is widely consumed as a nutritious food across the globe.

Study Design: Anti-ulcer study.

Place and Duration of Study: Department of Pharmacology and Therapeutics, Delta State University, Abraka, Delta State, Nigeria, between February and April, 2016.

Methodology: Forty-five rats divided into 9 groups of five were used for each model. Doses of 250 mg/kg, 500 mg/kg, and 1000 mg/kg of Musa sapientum (MS) alone and in combination with Vitamin C 100 mg/kg (1:1) were administered to the animals, Vitamin C 100 mg/kg was administered to another group, while the control group received distilled water. Omeprazole 20 mg/kg was given to a different group. The animals were sacrified and stomach was removed for examination.

Results: The aqueous extract of unripe fruit of Musa sapientum Linn showed significant (P<0.05) decrease in ulcer in both models, which was further enhanced by Vitamin C addition.

Conclusion: This study concludes that Vitamin C potentiates the anti-ulcerogenic effect of unripe fruits of Musa sapientum in rats.

Climate change is a threat to humanity. Current weather extremes are already affecting millions of people, putting food and water security at risk, and threatening agriculture supply chains and many ecosystems and resources. Climate change makes these events more frequent and extreme poor countries are getting exposed to greater risks compared to wealthier countries. The impacts of climate change affect the lives of both women and men in a number of ways. Concern is emerging that the negotiations on climate change do not fully involve the affected groups yet each of these groups is impacted by climate change in different ways. This paper addressed the impacts of climate change, the gender roles in adaptation process as different strategies were used in a pastoralist community. The study was conducted in Samburu East District of Kenya using participatory methods and approaches.  The study used survey method 180 households were randomly selected being a homogenous pastoralist community; gender and age were further used during purposive sampling to select the required household respondents. Focus group discussions, key informant interviews, life histories and observation were also used. The study findings indicated that the impacts of climate change were unequally felt along the gender lines in Samburu District. Women due to the community’s culturally gender constructed roles were found to be more vulnerable to the impacts as compared to their male counterparts. The adaptation process showed that women easily adapted and they had better strategies that led them to resilience. The study concluded that there was need to mainstream gender in the policies and legal frameworks that anchor the adaptation and mitigation of climate change in Kenya such that there is full participation of both men and women for burden sharing and sustainable development. The study confirmed that ethos and norms are key determinants of impact levels at the community social structure.

The stem and leaf anatomical studies of three species, Vernonia amygdalina Del. (Bitter leaf and Non-bitter leaf varieties), Cyanthillium cinereum (L.) H.Rob., and Brenandendron donianum (DC.) H.Rob., were carried out using a light microscope to determine their taxonomic relationships. In the recent past, plant species have been removed from their family or genera and classified under another taxon based on anatomical evidence. The anatomy of the stem showed a single layer of epidermis in all the taxa studied, 2-3 layers of collenchyma cells in V. amygdalina, 4-5 layers in C. cinereum and B. donianum. The vascular bundles are arranged in a concentric manner in V. amygdalina and C. cinereum while it is scattered in B. donianum. The scattered vascular bundles and absence of pith in B. donianum which is a characteristic feature of the monocotyledonous plant is unique and could be exploited for taxonomic purposes. The occurrence of bicollateral vascular bundles in B. donianum and open collateral in the other taxa studied could be of diagnostic importance. The anatomy of the midrib also showed a single layer of epidermis usually covered with a cuticle in all the taxa studied. The outline of the midrib is oblong in all the taxa studied. The bundle sheath consists of a cap of 1-3 layers of thick-walled sclerenchyma in B. donianum and thin-walled parenchyma in C. cinereum and the two different taxa of V. amygdalina. The collenchyma cells are 2 – 3 layers in V. amygdalina, 4-5 layers in C. cinereum and B. donianum. The vascular bundle is bicollateral in B. donianum and collateral in the other taxa studied. The variation in the type and arrangement of vascular bundles in the midrib is also of taxonomic importance. The similarities in the anatomy of the stem and leaf of V. amygdalina (bitter leaf) and V. amygdalina (non bitter leaf) suggest that the two taxa are the same species.