Length-weight relationships of fish from sandy beaches

This study estimated the length–weight relationships of 16 fish species occurring close to the shores of sandy beaches along the lower Negro River basin, Brazilian Amazon. The specimens were captured for one day each month, in October to November 2016, early in the morning and early evening, using trawl net (20 m taken for standard length (SL – 0.1 cm precision) and total weight (TW – 0.01 g precision). The parameters a and b of the equation WT = a.LTb were estimated. The a values ranged from 0.0018 to 0.0226 and b values ranged from 2.5271 to 3.3244. This study also provides new data on of maximum lengths for six species, Amazonsprattus scintilla, Brycon pesu, Moenkhausia megalops, Pachyurus paucirastrus, Reganella depressa and Trachydoras microstomus, and new reports of the LWRs parameters of 15 fish species.

Cultivation of Edible Tropical Bolete, Phlebopus spongiosus, in Thailand and Yield Improvement by High-Voltage Pulsed Stimulation

Tropical bolete, Phlebopus spongiosus, is an edible ectomycorrhizal mushroom indigenous to northern Thailand. This mushroom has the ability to produce fruiting bodies without the need for a host plant. In this study, the technological cultivation of P. spongiosus was developed. Cultivation experiments indicated that fungal mycelia could completely colonize the cultivation substrate over a period of 85–90 days following inoculation of liquid inoculum. Primordia were induced under lower temperatures, high humidity and a 12-h photoperiod. Mature fruiting bodies were developed from young fruiting bodies within a period of one week. Consequently, yield improvement of P. spongiosus cultivation was determined by high-voltage pulsed stimulation. The results indicated that the highest degree of primordial formation, number of mature fruiting bodies and total weight values were obtained in cultivation experiments involving a high voltage of 40 kV. The total weight of the mushrooms increased by 1.4 times after applying high-voltage pulses when compared with the control. Additionally, the results revealed that the size of the fruiting body and the proximate composition of the fruiting bodies from high-voltage stimulation treatments were not different from the control. This research provides valuable information concerning successful cultivation techniques and yield improvement by high-voltage pulsed stimulation for the large-scale commercial fruiting body production of P. spongiosus.

Does Shade Impact Coffee Yield, Tree Trunk, and Soil Moisture on Coffea canephora Plantations in Mondulkiri, Cambodia?

Shade is a natural condition for coffee plants; however, unshaded plantations currently predominate in Asia. The benefits of shading increase as the environment becomes less favorable for coffee cultivation, e.g., because of climate change. It is necessary to determine the effects of shade on the yield of Coffea canephora and on the soil water availability. Therefore, three coffee plantations (of 3, 6, and 9 ha) in the province of Mondulkiri, Cambodia, were selected to evaluate the effect of shade on Coffea canephora yields, coffee bush trunk changes, and soil moisture. Our study shows that shade-grown coffee delivers the same yields as coffee that is grown without shading in terms of coffee bean weight or size (comparing average values and bean variability), the total weight of coffee fruits per coffee shrub and the total weight of 100 fruits (fresh and dry). Additionally, fruit ripeness was not influenced by shade in terms of variability nor in terms of a possible delay in ripening. There was no difference in the coffee stem diameter changes between shaded and sunny sites, although the soil moisture was shown to be higher throughout the shaded sites.

L-Arginine Supplementation for Nulliparous Sows during the Last Third of Gestation

We evaluated the effects of L-arginine supplementation during the last third of gestation on molecular mechanisms related to skeletal muscle development of piglets and litter traits at birth. Twenty-three nulliparous sows averaging 205.37 ± 11.50 kg of body weight were randomly assigned to the following experimental treatments: control (CON), where pregnant sows were fed diets to meet their nutritional requirements; arginine (ARG), where sows where fed CON + 1.0% L-arginine. Skeletal muscle from piglets born from sows from ARG group had greater mRNA expression of MYOD (p = 0.043) and MYOG (p ≤ 0.01), and tended to present greater mRNA expression (p = 0.06) of IGF-2 gene compared to those born from CON sows. However, there were no differences (p > 0.05) in the histomorphometric variables of fetuses’ skeletal muscle. The total weight of born piglets, total weight of born alive piglets, piglet weight at birth, coefficient of variation of birth weight, and the incidence of intrauterine growth restriction (IUGR) piglets did not differ between groups. No stillborn piglets (p < 0.01) were verified in the ARG sows compared to CON group. The blood levels of estradiol (p = 0.035) and urea (p = 0.03) were higher in ARG sows compared to those from the CON group. In summary, our data show that arginine supplementation of nulliparous sows at late gestation enhance mRNA expression of key myogenic regulatory factors, which likely contribute to improve animal growth rates in later stages of development.

Natural Batch Adsorption Operation to Remove Dissolved Copper (II) by Carbon Charcoal Rambutan

Carbon charcoal was made from rambutan rods and used as an adsorbent. A gram 70/100 mesh size of adsorbent was then used to adsorb 100 ml of copper ion solution with a 70 ppm concentration. In this investigation, the batch procedure was used without shaking (naturally). The charcoal carbon rambutan ability to remove the copper ion was measured by AAS. The percentage result was 48,135% or about 33,694 ppm. SEM and EDX instrument analysis have applied to confirm the presence of copper ions on the adsorbent surface. The copper ion was found at a concentration of 0.09 percent of the total weight. The carbon charcoal adsorbent in rambutan rods has the ability to purify the water contaminated by metal ions.

An Extended Methodology for Sizing Solar Unmanned Aerial Vehicles: Theory and Development of a Python Framework for Design Assist

There is a growing interest in using unmanned aerial vehicles (UAVs) in the most diverse application areas from agriculture to remote sensing, that determine the need to project and define mission profiles of the UAVs. In addition, solar photovoltaic energy increases the flight autonomy of this type of aircraft, forming the term Solar UAV. This study proposes an extended methodology for sizing Solar UAVs that take off from a runway. This methodology considers mission parameters such as operating location, altitude, flight speed, flight endurance, and payload to sizing the aircraft parameters, such as wingspan, area of embedded solar cells panels, runway length required for takeoff and landing, battery weight, and the total weight of the aircraft. Using the Python language, we developed a framework to apply the proposed methodology and assist in designing a Solar UAV. With this framework, it was possible to perform a sensitivity analysis of design parameters and constraints. Finally, we performed a simulation of a mission, checking the output parameters.

The Volumetric Analysis of Porous Mixture Containing Modified Plastic Waste

Porous Asphalt mixture is an asphalt mixture that uses open graded which has a functions as a drainage so that rainwater will not generate aqua planning on the road surface. The purpose of this study was to analyse the volumetric of modified asbuton with plastic waste and with no plastic waste of a mixture of porous asphalt. In this study we used asphalt porous specimens with dimensions of 10 cm in diameter and 8 cm in height. The specimens were made in 3 variations: 0% plastic, 0.5% 1.0% plastic with 9 specimens. This study uses PET (Polyethylene Terephlate) and laboratory experimental-based, where the gradation of porous asphalt mixture refers to the specifications of the Road Engineering Association of Malaysia (2008). The results of this study describe that there was an increase in VIM value due to the addition of PET plastic waste which is plastic is a replacement of aggregate total weight.

Produktivitas rumput gajah (Pennisetum purpureum cv Taiwan) hasil irradiasi sinar gamma pada dosis 50 Gy

The study aims to determine the productivity of elephant grass cv Taiwan (Pennisetum purpureum cv Taiwan) from gamma ray irradiation at a dose of 50 gy at five harvest in one year. The study used a randomized block design (RBD) with 3 replications, the treatment was 51 numbers clone of elephant grass (P. purpureum cv Taiwan) from gamma ray irradiation and control (without irradiation). Observations were made on each number of elephant grass irradiated on 5 plants per number, and were made on 10 plantswith a harvest interval of 2 months. The observed parameters include the number of tillers; fresh and dry leaf weight; fresh and dry stem weight, and total weight. The results showed a significant impact of gamma radiation (P<0.05) on tiller count, fresh leaf weight, dry leaf weight and fresh stem weight as well as dry stem weight and total weight. These results show that gamma radiation on elephant grass can generate diversity and increase its productivity. The best cuttings can be made on the fourth cut in clones no. 19, 1, 27, 31 and 3.

Kondisi Biometrik Kerang Darah, Tegillarca granosa, di Pesisir Pantai Utara Kota Banda Aceh

The blood clam, Tegillarca granosa (Linnaeus, 1758) is one of the economically important aquatic organisms. Therefore, information related to biometric conditions is crucial as preventive and responsive efforts to manage blood clams. This study aims to analyze the biometric condition of blood clams collected from the northern coast of Banda Aceh City. Blood-clam samples were collected from three locations, namely Alue Naga, Tibang, and Deah Raya. A total of 300 blood clams were observed. The biometric parameters included the distribution of length and weight classes, the relationship between length and weight, condition factors, ratios, and correlations between total weight, meat weight, and shell weight were measured. The results showed that the majority of blood clams found in Deah Raya were in the smaller length and weight classes (30-32 mm and 12,25-17,24 g) compared to those found in Alue Naga (33-35 mm and 17,25-22,24 g) and Tibang (42-44 mm and 22,25-27,24 g). Despite having identical growth patterns (negative allometric) and condition-factor values, the blood clams collected from Alue Naga had higher meat weight ratios than those collected from the other two locations. The correlation values between the weight of the meat and the total weight of the blood clams collected from Deah Raya tends to be lower than those of blood clams obtained from Alue Naga and Tibang, which are 0,55; 0,81; and 0,78, respectively. Keywords: biometric, environmental factor, Deah Raya

Reproduction and fecundity of invader of internal insemination Trachelyopterus galeatus in a Neotropical floodplain

After the formation of Itaipu Reservoir, the invader Trachelyopterus galeatus colonized the upper Paraná River. Light microscopy was used to describe gametogenesis and the reproductive phases of females and males. The following data were verified: diameter of the oocytes, spawning type, batch fecundity by ovary weight, standard length, and total weight of the fish, along with the regions where this species reproduced in the upper Paraná River floodplain. A total of 470 specimens were collected quarterly in 2016, 2018 and 2019, and bimonthly in 2017. The gonads were fixed in a Karnovsky solution, dehydrated, infiltrated, and embedded in historesin. The histological slides were stained using PAS + iron hematoxylin + metanil yellow, analyzed and photographed under an image-capturing microscope. As regards diameter of the oocytes and fecundity estimates, ovaries whose oocytes were measured under a stereomicroscope were sampled. In the oogenesis, undifferentiated and differentiated oogonia, early primary growth oocytes, secondary growth oocytes, full-grown oocytes and maturing oocytes were recorded. In the spermatogenesis, primary and secondary spermatogonia, primary and secondary spermatocytes, spermatids and spermatozoa were recorded. The reproductive phases found for females and males were: immature, early development, late development, spawning/sperm-releasing capable, regression, and regeneration. Trachelyopterus galeatus prefers to occupy and reproduce in the Ventura, Patos, Guaraná, Fechada, Garças, and Pau Véio lagoons. The diameter of the oocytes varied from 0.4 to 2.9 mm. Females spawn, on average, 113 oocytes per batch. Batch fecundity variation shows that the larger the ovary, standard length, and total weight, the larger the number of oocytes to be spawned. This invader possesses reproductive success in the upper Paraná River floodplain, especially in lagoons.