Optimal Growth Conditions Research Articles

Effects of Temperature and Salinity on the Growth, Reproduction, and Carotenoid Accumulation in Artemia sinica and Transcriptome Analysis

Brine shrimp (Artemia), rich in carotenoids, are widely used in intensive aquaculture to supplement nutrients and enhance the coloration of farmed organisms. This study investigates the growth, reproduction, and carotenoid accumulation in Artemia sinica under varying salinity and temperature conditions. The results showed that temperature and salinity displayed significant interactions with survival, body length, and carotenoid accumulation in the body. The optimal survival and growth conditions of A. sinica (Bohai Sea Gulf) were a temperature range of 25–30 °C and a salinity range of 30–50‰. High temperatures accelerated growth and sexual maturity at the expense of survival rates, while temperatures below 20 °C prevented ovigerous development. Extreme salinity levels negatively affected survival and growth, though high salinity promoted sexual maturity. Carotenoids in A. sinica mainly accumulate as echinenone and canthaxanthin form. Carotenoid accumulation decreased with increased temperature and salinity, and the temperature effect decreased with rising salinity. A. sinica cultivated at a salinity of 10‰ and a temperature of 25 °C exhibits the highest carotenoid content. Transcriptomic analysis revealed that high temperatures primarily affected genes related to stress response and metabolism, while high-salinity regulated genes associated with ion balance and signaling pathways. These findings provide a theoretical basis for enhancing Artemia sinica aquaculture and optimizing cultivation conditions, offering novel insights into nutritional and environmental impacts on brine shrimp biology.

Profiling The Growth Conditions and Persistent Organic Pollutants (POPS) Tolerance of Phenoliferia glacialis USM-PSY62

Antarctica is characterized by extreme cold, isolated, and unique ecosystems. Nevertheless, Antarctica harbors diverse species of microorganisms, particularly in its ice-covered lakes and subglacial environments. These microorganisms have special adaptations to extreme cold and low-nutrient conditions. Some extremophiles, like psychrophiles can thrive in these harsh environments. Phenoliferia glacialis USM-PSY62, previously identified as Rhodotorula sp. USM-PSY62 is a psychrophilic yeast isolated from the ice brine of Antarctica. However, there is very little information on this psychrophilic yeast. This study aims to characterize the P. glacialis USM-PSY62 through the identification of the optimum growth parameters in different media (Yeast Peptone Dextrose, YPD & Yeast Malt, YM), temperature (4°C, 15°C, 20°C) and pH (6, 7, 8, 9) as well as their ability in carbon assimilation and extracellular enzyme production. It has an optimal growth in YPD compared to YM broth media. P. glacialis USM-PSY62 grows optimally at 15°C and pH 7.0. This Antarctic yeast enters the stationary phase on day six of incubation under optimum conditions. It appeared mainly as elongated-shape and oval-shaped with budding formation and was found to produce extracellular enzymes such as protease and amylase in the presence of 2% glucose concentration in YM media. P. glacialis USM-PSY62 also can assimilate various types of carbon sources including raffinose, arabinose, and maltose. Interestingly, the psychrophilic yeast presented growth in media supplemented with Persistent Organic Pollutants (POPs) such as dichlorophenyldichloroethylene (DDE) and polychlorinated biphenyl (PCB). These preliminary findings suggest that P. glacialis USM-PSY62 has tremendous potential for bioremediation application in polluted cold regions, as well as deepening our knowledge of its optimal growth conditions.

Duration of Light Exposure Using White Light-Emitting Diode (LED) on the Performance of White Oyster Mushroom (Pleurotus ostreatus L.)

Background: In the dynamic world of mushroom cultivation, optimizing growth conditions is paramount for maximizing yield and quality. This research sought to evaluate the influence of varying hours of exposure to white light through light-emitting diodes (LED) on growth and yield performance of white oyster mushroom (Pleurotus ostreatus L.). Its aim was to determine the most effective light exposure duration for enhancing mushroom growth and yield. Research Design: Using a completely randomized design (CRD), the study used four treatments: 8 hours of lighting (T1), 12 hours of lighting (T2), 16 hours of lighting (T3), and a control group that received natural light (T4). The study was conducted in Palayamanan (8° 27’ 5.3118" N and 126° 9’ 59.7739" E) area at North Eastern Mindanao State University’s -Tagbina Campus from July 2023 to November 2023. Results: Results from the study provided interesting insights into the indirect nature of the relationship between light exposure and mushroom development. The findings of the study indicate that the duration of light exposure significantly affects the growth and yield of white oyster mushrooms. Both mycelium growth (29.80 days) and fruiting body formation (7.83 days), as well as harvesting time (10.87 days), were improved by 12 hours of lighting, while the control group consistently showed poor performance. Conclusion: Based from the analysis, it is evident that 12 hours of lighting consistently performed very well, with the exception of a minor under-performance in the case of yield per harvest, suggesting that 12 hours might be the ideal duration. Hence, 16 hours of lighting also demonstrated some advantages in certain variables, indicating potential for further study.

High-Density Fermentation of Lactobacillus plantarum P6: Enhancing Cell Viability via Sodium Alginate Enrichment

Lactobacillus plantarum exhibits a wide range of beneficial physiological functions, including maintaining intestinal microbiota balance, reducing serum cholesterol, and promoting digestive health. According to the specific nutrient requirements of Lactobacillus plantarum P6, we investigated the effects of various carbon sources, nitrogen sources, trace elements, growth-promoting substances, as well as the initial pH and inoculum size on the growth of Lactobacillus plantarum P6 under fermentation conditions. The optimal growth conditions for Lactobacillus plantarum P6 were identified to facilitate high-density fermentation in small-scale fermenter production, achieving a cell concentration of 1.03 × 1011 CFU/mL. This resulted in a 2.5-fold increase in bacterial wet weight, and fermentation time was reduced to 12 h when utilizing a specific medium enriched with 0.2% sodium alginate. It is hypothesized that sodium alginate forms a protective film around the bacterial cells, promoting cell aggregation and enhancing self-coalescence, potentially triggering a bacterial community effect. These results provide a basis for the industrial-scale high-density cultivation of Lactobacillus plantarum, offering potential for enhanced biotechnological applications.

Analysis of Soil Viability Monitoring System for In-House Plantation Growth Using an Internet of Things Approach

Houseplant cultivation has become increasingly popular, allowing individuals to bring nature into their homes. However, successful indoor gardening requires careful monitoring of soil parameters to ensure optimal plant growth. To address this need, sensor technology and Internet of Things (IoT) devices are utilized to monitor soil temperature and moisture levels, which play crucial roles in plant growth. Various soil factors are sensed and collected using an IoT-based microcontroller, with data transmission facilitated by a Message Queue Telemetry Transport (MQTT) broker. Visualization of the data is achieved through the Node-RED programming tool, simplifying dashboard creation for easy monitoring. Furthermore, the collected data is stored in a MySQL server, enabling further analysis through SQL queries. The day is divided into four quarters with six-hour intervals, allowing for soil data collection using temperature and moisture sensors. The resulting information on the dashboard facilitates informed decision-making to enhance soil conditions for optimal indoor plant growth. Experimentation has revealed a reduction in soil temperature of 3°C during daytime due to air conditioning operation, while soil moisture content remains consistently between 60 to 65% during early mornings and late evenings. Additionally, emphasis is placed on remote management using IoT systems, enabling monitoring of plant growth even when access is limited. Overall, monitoring soil factors using IoT technology offers a promising approach to optimizing indoor gardening practices and minimizing environmental resource consumption.

Biology and host specificity of the stem-boring weevil Gasteroclisus tricostalis, a candidate agent for the biological control of fireweed (Senecio madagascariensis) in Australia

ABSTRACT Senecio madagascariensis Poiret (Asteraceae) is a target for biological control in Australia, due to substantial impacts on agriculture and native environments. Studies in the plant’s native range in South Africa prioritised the stem-boring weevil Gasteroclisus tricostalis (Thunberg) (Curculionidae) as a candidate agent. In this study, we assessed the biology and host specificity of G. tricostalis during laboratory trials conducted in both South Africa and Australia. No-choice trials in South Africa revealed that, despite oviposition on 15 non-target Senecio species (seven Australian and eight South African), there was significantly lower oviposition relative to S. madagascariensis, with no survival to pupation or adulthood on any non-target species. In contrast, no-choice tests in quarantine in Australia, recorded oviposition on 12 non-target Australian native Senecio species, with oviposition on two species not significantly different to that on S. madagascariensis. Furthermore in Australia, larvae developed to adulthood on five non-target species, in numbers that were not significantly different to S. madagascariensis. These discrepancies can mostly be explained by the lower phylogenetic distance from S. madagascariensis to the susceptible non-target species tested in Australia and, likely, optimal plant growth conditions in quarantine in two cases. Although no-choice tests are renowned for their conservative nature, preliminary paired-choice trials in both South Africa and Australia failed to demonstrate clear oviposition preferences for S. madagascariensis. These results suggest that, given the high diversity of the genus Senecio in Australia, the weevil is likely unsuitable for release and further trials were suspended.

Exogenously Applied Gibberellic Acid Alters Cannabinoid Profile in Cannabis sativa L.

Cannabis sativa (C. sativa L.) has garnered significant attention worldwide due to its widespread use as a pharmaceutical agent. With the increasing clinical application of C. sativa and cannabinoid therapeutics, there is strong interest in the development of superior plant varieties and optimisation of growth conditions to enhance secondary metabolite yield. Our RNA sequencing analysis revealed differential expression of hormone-related transcripts in developing C. sativa trichomes, suggesting the involvement of hormone signalling pathways in cannabinoid production. Leveraging the potency of exogenous hormones on plants, this study sought to determine if the application of cytokinin (CK), gibberellic acid (GA) and jasmonic acid (JA) modified trichome morphology and the cannabinoid profile over an 8-week period following the induction of flowering. Exogenous hormone application led to alterations in trichome morphology, with each treatment significantly reducing trichome head width by the final week of assessment. Interestingly, GA application also resulted in a significant reduction in the concentration of Δ-9-tetrahydrocannabinol (THC), Δ-9-tetrahydrocannabinolic acid (THCA), cannabidiol (CBD) and cannabidiolic acid (CBDA) by week 8 post floral induction, however, JA and CK treatment did not consistently modulate the accumulation of these cannabinoids. The minor cannabinoids, cannabidivaranic acid (CBDVA), cannabicyclolic acid (CBLA), cannabicyclol (CBL), cannabichromene (CBC), cannabigerolic acid (CBGA) and cannabigerol (CBG), were also affected by hormone treatments, with varying degrees of accumulation observed. These findings underscore the intricate interplay between phytohormones and secondary metabolite biosynthesis in C. sativa. Our study highlights the potential of hormone modulation as a strategy to enhance cannabinoid yield and offers some insights into the regulatory mechanisms governing cannabinoid biosynthesis in C. sativa trichomes.

Random alloy growth of AlAs0.08Sb0.92 on GaSb under high Group-V flux condition

The growth of AlAsxSb1-x epilayers with x < 0.1 is crucial for various optoelectronic device applications. However, achieving the desired alloy composition and lattice-matched condition remains challenging. In this study, the epitaxial growth of the random alloy AlAsSb on GaSb was investigated using molecular beam epitaxy. The objective was to determine the optimal growth condition to obtain AlAs0.08Sb0.92 on GaSb (lattice-matched to GaSb) with a high growth rate and under a high group-V/III beam equivalent pressure (BEP) ratio. The growth parameters, including the group-V/III BEP ratio, growth rate, and temperature, were studied to monitor the change in the structural properties of the AlAsSb epilayer. It was shown that the As incorporation in AlAsSb was higher than expected at high growth rate and under high Sb BEP condition. The results demonstrated that increasing the growth temperature while decreasing the As BEP did not significantly improve the crystal quality where the optimization of group-V/III BEP ratio and As BEP is effective to obtain AlAs0.08Sb0.92 on GaSb and enhance the crystal quality. The findings provide valuable insights into the growth dynamics of AlAsSb to achieve high quality and lattice-matched epilayers grown on GaSb which is well-suited for a range of optoelectronic applications.

Biofeedback-Based Closed-Loop Phytoactuation in Vertical Farming and Controlled-Environment Agriculture.

This work focuses on biohybrid systems-plants with biosensors and actuating mechanisms that enhance the ability of biological organisms to control environmental parameters, to optimize growth conditions or to cope with stress factors. Biofeedback-based phytoactuation represents the next step of development in hydroponics, vertical farming and controlled-environment agriculture. The sensing part of the discussed approach uses (electro)physiological sensors. The hydrodynamics of fluid transport systems, estimated electrochemically, is compared with sap flow data provided by heat-based methods. In vivo impedance spectroscopy enables the discrimination of water, nutrient and photosynthates in the plant stem. Additionally to plant physiology, the system measures several air/soil and environmental parameters. The actuating part includes a multi-channel power module to control phytolight, irrigation, fertilization and air/water preparation. We demonstrate several tested in situ applications of a closed-loop control based on real-time biofeedback. In vertical farming, this is used to optimize energy and water consumption, reduce growth time and detect stress. Biofeedback was able to reduce the microgreen production cycle from 7 days to 4-5 days and the production of wheatgrass from 10 days to 7-8 days, and, in combination with biofeedback-based irrigation, a 30% increase in pea biomass was achieved. Its energy optimization can reach 25-30%. In environmental monitoring, the system performs the biological monitoring of environmental pollution (a low concentration of O3) with tomato and tobacco plants. In AI research, a complex exploration of biological organisms, and in particular the adaptation mechanisms of circadian clocks to changing environments, has been shown. This paper introduces a phytosensor system, describes its electrochemical measurements and discusses its tested applications.

Influence of multi-stress factors on the growth of Chlorella pyrenoidosa and Scenedesmus abundans using response surface methodology.

This study evaluated the biofuel production potential of two algal species, Chlorella pyrenoidosa and Scenedesmus abundans, under stress conditions induced by nutrient supplementation or starvation at varying light intensities. Central composite face-centered design response surface methodology (CCFD-RSM) was employed to optimize stress conditions by varying the sodium nitrate (NaNO3), potassium dihydrogen phosphate (KH2PO4), dipotassium hydrogen phosphate (K2HPO4), cultivation time, and light intensity. The study included both C. pyrenoidosa and S. abundans, which presented increased biomass yields when subjected to nutrient starvation. Under the optimized conditions, the dry biomass yield was 98.26mg/L for C. pyrenoidosa and 110mg/L for S. abundans. Lipid yields were approximately 22.47% for C. pyrenoidosa and 29.06% for S. abundans under these optimized growth conditions. The optimized parameters for maximum biomass and lipid production were identified as C. pyrenoidosa, and the optimized conditions required 0.805g/L NaNO3, 0.052g/L K2HPO4, 0.099g/L KH2PO4, 17days of culture, and 5168.39lx of light intensity. For S. abundans, the optimal conditions were 1.065g/L NaNO3, 0.071g/L K2HPO4, 0.058g/L KH2PO4, 22days of cultivation, and 2897lx of light intensity. Overall, both C. pyrenoidosa and S. abundans have emerged as promising candidates for sustainable biodiesel production, highlighting their potential under stress conditions induced by nutrient modulation and variable light intensities.

Enhancement of paclitaxel production by Neopestalotiopsis vitis via optimization of growth conditions.

Accessibility of paclitaxel and other taxoids from natural resources is restricted. Endophytic fungi are novel, rapidly growing resources for producing these compounds. Neopestalotiopsis vitis (N. vitis) has been recently isolated from Corylus avellana, and its ability to produce a variety of taxoids has been detected and confirmed by analytical methods. Simultaneous growth and high production of taxoids by application of different sorts and concentrations of carbon and nitrogen were targeted in the present research. These criteria were assessed in different acidities (pH 4.0-7.0), carbon sources (sucrose, fructose, glucose, mannitol, sorbitol, and malt extract), and nitrogen forms (urea, ammonium nitrate, potassium nitrate, ammonium phosphate, and ammonium sulfate) by testing one parameter at a time approach. The first analysis introduced pH 7.0 as the best acidity of the medium for N. vitis, where the highest paclitaxel yield was generated. Further analysis introduced 3% Malt extract as the best carbon-providing medium. In the next step, the effects of nitrogen forms on the growth rate, paclitaxel yield, alkaloids, and amino acid contents were evaluated. Based on the results of this experiment, 5 mM ammonium sulfate was selected as the best nitrogen source to obtain the maximum biomass and paclitaxel yield. Overall, the results introduce a medium containing 3% (w/v) malt extract and 5 mM ammonium sulfate at pH 7.0 as the best medium in which N. vitis produces the highest paclitaxel yield coincident with rapid and sustainable growth. The findings pave the way for industrial manufacturing of taxoids.

Laser assembly of CeO2 nanobrushes and their resistive switching performance

Memristors in a metal/oxide/metal configuration emerge as an advanced non-volatile information storage technology due to their high operating speed and low power consumption. Understanding the role of the microstructure of the active oxide layer in its resistive switching (RS) performance is scientifically important for revealing the conduction mechanism of oxides, and technically critical for the development of high-performance memristors. Here, self-assembly of vertically aligned CeO2 nanobrushes, a typical RS material, is demonstrated in pulsed laser epitaxy. The growth map of CeO2 is fully explored, and optimized growth conditions for CeO2 nanobrushes are established. Microstructure and crystallinity characterizations reveal the single-crystalline epitaxy nature of CeO2 nanobrushes. A nanobrush memristor exhibits a threshold switching feature with an On/Off ratio of 50, as 16 times high as a thin-film memristor, and excellent endurance of up to 500 cycles and retention time of up to 104 seconds. Theoretical fitting of the I-V curves of the thin-film and nanobrush memristors show interfacial switching in the thin-film memristor and filamentary switching in the nanobrush memristor. The distinct RS mechanisms between thin films and nanobrushes suggest the fundamental role of the structural design of active oxide layers in the RS performance of oxide-based memristors.

Internet of Things-Driven Precision in Fish Farming: A Deep Dive into Automated Temperature, Oxygen, and pH Regulation

The research introduces a revolutionary Internet of Things (IoT)-based system for fish farming, designed to significantly enhance efficiency and cost-effectiveness. By integrating the NodeMcu12E ESP8266 microcontroller, this system automates the management of critical water quality parameters such as pH, temperature, and oxygen levels, essential for fostering optimal fish growth conditions and minimizing mortality rates. The core of this innovation lies in its intelligent monitoring and control mechanism, which not only supports accelerated fish development but also ensures the robustness of the farming process through automated adjustments whenever the monitored parameters deviate from desired thresholds. This smart fish farming solution features an Arduino IoT cloud-based framework, offering a user-friendly web interface that enables fish farmers to remotely monitor and manage their operations from any global location. This aspect of the system emphasizes the importance of efficient information management and the transformation of sensor data into actionable insights, thereby reducing the need for constant human oversight and significantly increasing operational reliability. The autonomous functionality of the system is a key highlight, designed to persist in adjusting the environmental conditions within the fish farm until the optimal parameters are restored. This capability greatly diminishes the risks associated with manual monitoring and adjustments, allowing even those with limited expertise in aquaculture to achieve high levels of production efficiency and sustainability. By leveraging data-driven technologies and IoT innovations, this study not only addresses the immediate needs of the fish farming industry but also contributes to solving the broader global challenge of protein production. It presents a scalable and accessible approach to modern aquaculture, empowering stakeholders to maximize output and minimize risks associated with fish farming, thereby paving the way for a more sustainable and efficient future in the global food supply.

Novel characterisation of Curvularia geniculata associated with leaf blight on Costus igneus in India

Costus igneus Nak, commonly referred as insulin plant or spiral flag, is a perennial herb belonging to the family Costaceae. Owing to its ability to regulate the blood sugar level, it is considered as a boon plant for diabetic patients, hence popularly known as the “sugar plant”. Although few foliar diseases have been documented on C. igneus, they generally occur in minor frequency under Indian conditions. However, in May 2022, a moderate to severe incidence of leaf blight was observed on insulin plants at University of Agricultural Sciences, GKVK, Bangalore, and nearby medicinal gardens. The affected leaves exhibited light brown lesions coalesced to form papery blight, gradually leading to complete drying of leaves. The current study aimed to identify, characterize, and document the fungal pathogen responsible for the disease, with a focus on its morphological, molecular, and biological characteristics to ensure accurate identification. Additionally, the study sought to determine optimal conditions for pathogen growth and sporulation to support the development of effective disease management strategies. The associated fungus was isolated, purified and identified as Curvularia geniculata through morphological and multigene phylogenetic analysis, using internal transcribed spacer (ITS) and large sub unit (LSU) regions of rDNA, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene. Biological characterization revealed that cornmeal agar (CMA) at 30 °C and pH of 7 were ideal for better growth and abundant sporulation. These findings, highlighting the emergence of C. geniculata as a novel fungal pathogen infecting C. igneus in India, are crucial for developing effective disease management strategies to safeguard the medicinal properties of the plant.

Staphylococcus pseudintermedius ST2660 isolated from a cat has strong biofilm-forming ability and increases biofilm formation at cat’s normal body temperature

Staphylococcus pseudintermedius has been isolated from dogs, cats, and horses and is also known as an emergent zoonotic agent. We administered orbifloxacin, a fluoroquinolone, to treat bacterial infections of cutaneous wounds caused by excessive grooming of the skin in contact with the subcutaneous port of the subcutaneous ureteral bypass (SUB) system in a cat. However, after 80 days of treatment, a severe abscess was observed in the wound and fluoroquinolone-resistant S. pseudintermedius was isolated from the abscess. The isolate was identified as a novel sequence type (ST) 2660 and contained genes for leukocidins (lukS and lukF), exfoliative toxin (siet), and biofilm regulation (icaA and icaD). The isolate was resistant to macrolide, lincosamide, fluoroquinolone, and tetracycline classes. In addition, the isolate had strong biofilm-forming ability which significantly increased with culturing at 39 °C compared with that at 37 °C, suggesting that the isolate prefers a cats’ body temperature as the optimal biofilm growth condition. Notably, the biofilms were increased in the presence of doxycycline with culturing at 39 °C. This study is the first report in Japan on the new sequence type of S. pseudintermedius isolated from a companion animal and clarifies the distinctive virulence of S. pseudintermedius.

Spatial Variation of Microclimatic Parameters Inside a Polyhouse with Fog Cooling System

The importance of protected cultivation is increasing day by day due to its capability of producing crop all round the year and increase in the crop productivity. This advantage of protected cultivation can be efficiently achieved by adapting the polyhouse cultivation. To obtain the maximum crop productivity inside a polyhouse, it is necessary to understand the variability of microclimate inside it. The present study aims to understand the spatial variability of microclimate inside a naturally ventilated polyhouse installed with fog cooling system during summer season. The main aim of the study is to understand the effect of fogging system in spatial variability of microclimate. For the study, the data of microclimatic parameters were collected daily from April to June at four different time intervals 8.30 AM, 12.30 PM, 4.30 PM and 8.30 PM. The data recorded was then analyzed in Golden Surfer Software to generate contour plots of weekly averages of microclimate parameters. The analysis revealed that the temperature and relative humidity varied across the polyhouse depending upon the wind velocity and its distribution pattern. The light intensity varied based upon the orientation of polyhouse and the position of sun. Carbon dioxide concentration varied based on temperature, light intensity, crop transpiration and respiration. It can be concluded that, inside a naturally ventilated polyhouse, the microclimate varied both spatially and temporally with fogging system also due to wind effect. Thus, having accurate understanding of the microclimate inside a polyhouse helps to maintain optimal conditions for plant growth and thus improve crop yield and productivity.

Isolation and characterization of two new species, Hymenobacter mellowenesis sp. nov. and Hymenobacter aranciens sp. nov., from soil.

Strains M29T and ASUV-10-1T, which are aerobic, non-flagellated, and Gram-stain-negative, were isolated from soil samples collected in Inje (37°57'49.1"N 128°19'53.7"E) and Cheonan City (36°48'47.1"N 127°05'22.4"E), South Korea. Phylogenetic analyses based on rRNA gene sequences revealed that strains M29T and ASUV-10-1T form a distinct branch within the family Hymenobacter (order Cytophagales, class Cytophagia). Strain M29T is most closely related to Hymenobacter rubidus DG7BT with a 16S rRNA gene sequence similarity of 97.05%. Strain ASUV-10-1T shows closest genetic similarity to Hymenobacter frigidus B1789T (96.42%), Hymenobacter jeongseonensis BT683T (95.97%), and Hymenobacter terricola 3F2TT (95.65%). The optimal growth conditions for these strains are pH 7.0, no NaCl, and a temperature of 25°C. The dominant cellular fatty acids identified in these strains are iso-C15:0, anteiso-C15:0, and Summed Feature 3 (C16:1ω 7c / C16:1ω 6c). Both strains predominantly contain MK-7 as the respiratory quinone. The major polar lipids in strains M29T and ASUV-10-1T are phosphatidylethanolamine, aminophospholipid, and aminolipid. Based on biochemical, chemotaxonomic, and phylogenetic data, it is evident that M29T and ASUV-10-1T represent new species within the genus Hymenobacter. The new species were classified based on biochemical and chemotaxonomic characteristics. The taxonomic classification of these species was conducted following the guidelines and protocols outlined in Bergey's Manual of Systematic Bacteriology. We followed the methods for determining physiological and biochemical characteristics, as well as chemotaxonomic markers such as fatty acid profiles, quinone types, and polar lipid compositions. We also compared with the results of carbohydrate utilization and enzyme activities results [Bergey 1994]. Therefore, we propose the names Hymenobacter mellowenesis for strain M29T (= KCTC 102056T = NBRC 116578T) and Hymenobacter aranciens for strain ASUV-10-1T (= KCTC 92969T = NBRC 116575T).

Identification and characteristics of Plesiomonas shigelloides isolated from Mastacembelus armatus

Plesiomonas shigelloides (P. shigelloides), a dominant pathogenic strain identified as YY001, was successfully isolated and characterized from the hepatopancreas of diseased Mastacembelus armatus (M. armatus) for the first time. The strain was identified through a comprehensive approach that included morphological, physiological, and biochemical characterization, as well as 16S rRNA, 23S rRNA, and gyrB gene sequence analysis. Strain YY001 is classified as a Gram-negative bacterium, with optimal growth conditions observed at 28°C and pH 7.0. Results from the bacterium hemolysis test indicated the absence of hemolytic activity in YY001. However, the strain exhibited amplification of nine virulence genes: nanE, waaA, clpP, ssb, actP, aphA, astA, astD, and astB. Drug-resistance testing showed that YY001 displayed resistance only to penicillin G, oxacillin, norfloxacin, and tetracycline, while remaining sensitive to the majority of other antibiotics. Furthermore, nine drug-resistance genes, including emrD, catB, macB, ksgA, tolC, bacA, MdfA, sul1, and DegP, were detected through amplification. Experimental infection demonstrated that YY001 induced symptoms such as abdominal swelling, visceral edema, and hemorrhage, with hepatopancreatic manifestations being particularly severe. The median lethal dosage of strain YY001 in M. armatus was 9.7×108 colony-forming units (CFU)/mL within 48 h, and 4.9×106 CFU/mL within 192 h under the conditions of intraperitoneal injection. The hepatopancreas, gill, and intestine of infected fish showed obvious pathological symptoms, including tissue loosening, hemorrhage, and cell necrosis. The results of this study provided evidence for a more comprehensive understanding of P. shigelloides strain YY001 infection in M. armatus.

CFD Analysis to Optimize Air Quality in Aeroponic Tower Garden

Aeroponic tower gardens represent an innovative approach to urban agriculture, utilizing vertical structures to cultivate plants without soil. Research highlights the efficiency of this method in optimizing resource usage, such as water and space, compared to traditional farming. Studies emphasize increased crop yields, faster growth rates, and reduced environmental impact. Additionally, aeroponic systems enable precise nutrient delivery to plants, fostering optimal growth conditions. While the technology shows promise, further investigations are needed to address potential challenges and optimize its application in diverse agricultural settings. The study presents the simulation of air temperature and humidity distribution in a closed chamber of the vertical farm for optimization purposes. The environmental conditions inside the chamber are optimized for plant growth, to maintain the temperature at a range of 18-24 °C temperature and the relative humidity at a range of 75-85 %. The paper also discusses the challenges, limitations, and future recommendations for improving the system. Simulation of the system, on the other hand, is crucial not only for prototype fabrication but also for the optimization of sensor locations. The simulation of the tower garden system was performed using ANSYS-FLUENT to portray how the airflow inside the tower garden's enclosed environment was distributed. The system parameters such as humidity and temperature were set to meet the plants' growth requirements, and the system was treated as the steady state with an adiabatic boundary. Based on the simulation results, the best design recommended is to use two humidity and temperature sensors, one at the top and the other at the core of the prototype. Hence, a complete mapping of temperature and humidity distribution that is critical for plant growth would be occurred.

Growth and performance of n++ GaN cap layer for HEMTs applications

Apart from providing high-quality ohmic contacts to III-N devices, n++ GaN cap layers can eliminate surface-related current collapse effects in high-electron-mobility transistors (HEMTs). Various metal-organic chemical vapor deposition conditions and n-type doping are tested in GaN growth on sapphire by using triethylgallium as a Ga precursor, replacing more conventional trimethylgallium. Consequently, despite relatively low temperature of the growth at 800 °C to facilitate InAlN barrier capping, optimized growth conditions and SiH4 flow provided free electron concentration of 7.2 × 1019 cm−3 and mobility of 103 cm2/Vs. Moreover, electron concentration in the range of 1020 cm−3 is demonstrated by using flow modulation epitaxy. On the other hand, as calibration growths indicated, excessive SiH4 flow alone can lead to high density of edge dislocations and surface undulations without enhancing free electron concentration. 6 nm (Si: 4.2 × 1019 cm−3) and 8 nm thick (Si: 7.2 × 1019 cm−3) n++ GaN cap is implemented in normally-off n++ GaN/InAlN/AlN/GaN HEMTs grown on Si, with a collapse-free performance for the latter case. By calculating energy band and free carrier concentration profiles of the heterostructures it is shown, that free electrons of a sufficiently thick and doped n++ GaN cap can shield the channel from the unstable surface potential.