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Aquaculture procedures usually induce stress that affects the physiological status of fish. For this reason, the inclusion of additives in fish feeds to palliate stress might be a good alternative. This study aimed to assess the antimicrobial activity of citronella (Cymbopogon nardus) essential oil (CEO) against bacterial pathogens and to determine its dietary impact on the growth performance of Sparus aurata. In vitro tests confirmed that CEO possesses antimicrobial activity against several fish-specific pathogens. For the in vivo tests, three experimental groups were fed for 60 days with different concentrations of CEO: CTRL (0 mL kg(-1) fish feed); CEO1 (1 mL kg(-1) fish feed); and CEO2 (2 mL kg(-1) fish feed). At the end of the experiment, the physiological status was characterized. Subsequently, the specimens of the CTRL and CEO2 groups were subjected to a challenge with an injection of Poly I:C for immune stimulation. Although S. aurata individuals tolerated CEO inclusion without compromising growth performance, it significantly reduced glycogen in the CEO2 group, concomitant to an increment of total peripheral leucocytes. Moreover, different hematological profiles' responsive patterns against an inflammatory stimulus were observed. In conclusion, our results suggest that the use of CEO as a fish feed additive can prevent bacterial outbreaks and improve potential in vivo disease resistance in S. aurata without negatively affecting growth.

Tick-bornediseases are a significant human public health as well a livestock health problem in Pakistan. A survey study was carried out in lower Sindh (Tharparkar, Badin, Hyderabad, Karachi, Tando Muhammad Khan, Thatta, and Mirpurkhas). Thirteen hundred and sixty (1360) “tick samples” were collected randomly from infested Cattle, buffalo, sheep, and goats and then transported to the Parasitology laboratory, Sindh Agriculture University, Tandojam. the study was designed to investigate seasonal variation in prevalence of ticks and genus wise tick identification using the key for the tick samples of cattle, Buffalo, sheep and goats. Methodology: Investigations were performed throughout the year to record tick prevalence in various seasons, Ticks were identified on the basis of mouth parts, particularly position of the capitulum, genital aperture, festoons. Results:1360(Mean=544) were observed animals, 528(Mean=132) were the infested animals. The Study reveals the highest rate of tick infestation in the month of July(74.0, 47.5, 50,65.21%) in Cattle, Buffalo, Sheep, and Goats respectively, while the lowest rate of tick infestation was observed in the month of December(11.7,18.1, 16, 21.42%) in Cattle, Buffalo, Sheep, and Goats respectively-. Ticks collected from all districts of lower Sindh were subjected to genus wise identification and the most commonly infested ticks were belonging to the genus Hyalomma (27.5%) followed by Rhipicephalus (24.29%), Boophilus (22.80%), and Amblyomma (14.20%). Conclusion: Mild temperature and high relative humidity were identified supporting abiotic factors for tick infestation. The intensity of infestation increase with age and female host were more prone to infestation, Weak animals and cottage structures or houses were more considered as risk factors tick infestation.

The present research project was designed to calculate the Cutaneous Leishmaniasis infection in dogs few districts of Sindh, Pakistan. Dogs were screened for Cutaneous Leishmaniasis and potential Leishmaniasis positive cases were identified on the basis of active skin lesions. Affected tissues were collected and processed for Histo-pathological analysis. Dermal tissues of 35 domestic and 10 stray dogs were collected from Dadu, Hyderabad, and Jamshoro revealed that out of 45 dog samples, 30(66.66%) were positive for Cutaneous Leishmaniasis. The percentage of infection was 15(33.33%) positive in district Dadu, 10(22.22%) from district Hyderabad and 05 (11.11%) from district Jamshoro.

Analysis of a model is always a hot area of research. The quality of a feature model plays a significant role in software production because it is being used in product development. In this paper, along with the verification of errors in feature models we are validating our previous work where we have presented algorithms for the detection of quality level for a given feature model. Here, we are presenting the linear formulas of the feature models that we use as input for the quality detection algorithms. Further, this version is validating our semantics based quality detection technique of feature models.

This paper presents a comparative analysis of a physical model with Simulation for Hybrid Power Generation System. The Modeling and Simulation presented in this paper are based on two renewable sources i-e wind & solar. Both the mentioned sources were utilized with concerned power generation system i-e wind turbine and solar panel respectively. To enhance power generation capacity of solar panel, dual axis solar tracker was designed and significant change in average power generation capacity of solar panel was observed. As dual axis solar tracker was capable of inclining the solar panel to the sun throughout the year with servo based maneuvering to reciprocate minor changes in sun’s position during summer and winter. The paper is concerned with profound study regarding deviations in system parameters with variance in environmental parameters i-e insolation and temperature for solar source and velocity of wind along with Betz limit for wind source. It was made tangible by considering almost all the parameters involved in actual power generation to be included in simulation of the system and the results obtained from simulation were compared with those of real system & notable results were achieved with negligible differences in both actual and simulation based model.

According to Watson-Crick base pairing, Guanine binds to Cytosine and Adenine binds to Thymine to form a double helix DNA molecule; however, it is observed that guanine can also bind with another guanine through hoogesteen hydrogen bonding at about 90 degrees. Thus a tetrad is formed if four guanines are attached with each other. These tetrads are the cause of the formation of unusual structures called G-quadruplex structures. These structures not only formed by a single guanine rich nucleic acid sequence but their formation is also possible by two or four parallel sequences collectively. These structures (or guanine rich sequences through which they are formed) affect a well known technology named Affymetrix GeneChip which is popular for gene expression measurement effectively and cheaply. Since the nucleic acid sequences are placed very closely on GeneChip, they are able to interact with each other and then form G-quadruplex structures. In this case, they are not ready to hybridize with their target sequences. It is found that raw or hybridization level data of human, mouse and rat (mammalian in general) are affected by guanine rich sequences. This paper exhibits that GeneChips of two Bacterias are also affected by guanine-guanine interaction and hence measurement of gene expressions using these chips could be misleading.

El uso abusivo de antibióticos en la acuicultura produce un impacto negativo en el medio ambiente, además de generar patógenos resistentes a los antibióticos. En este sentido, y para minimizar los efectos de estos quimioterápicos sobre los peces cultivados, el medio ambiente y los consumidores, se han evaluado otras terapias alternativas, entre las que se encuentra el uso de extractos de plantas con capacidad antimicrobiana. El objetivo del presente estudio consistió en evaluar el potencial antimicrobiano de algunas sustancias naturales, como método de control de enfermedades bacterianas en la acuicultura. Se realizó una primera selección de sustancias en base a su capacidad de inhibición de tres patógenos de peces: Vibrio harveyi, Photobacterium damselae subsp. piscicida y Aeromonas hydrophila. Seguidamente se calculó la toxicidad potencial de las sustancias mediante la observación de la disminución de la bioluminiscencia de Vibrio fischeri, siendo el aceite de clavo la sustancia más tóxica, con una concentración efectiva 50 (EC50) de 0,059 μL mL-1. Posteriormente se determinó la capacidad de las sustancias de interferir el fenómeno quorum sensing, por la que algunas bacterias patógenas coordinan la expresión de ciertos factores de virulencia. Los resultados obtenidos mostraron que, excepto el aceite de citronella, todas las sustancias ensayadas tuvieron capacidad de inhibición del quorum sensing. Tras estos procesos selectivos se eligió seguir con los ensayos con el ajo y el aceite de clavo. Para conocer si mantenían sus propiedades antimicrobiana tras los procesos de extracción y almacenamiento, se realizaron ensayos de viabilidad a distintas temperaturas (63, 37, 22 y 4 °C) y tiempos de almacenamiento (1, 3 y 7 días). El ajo disminuyó su capacidad antimicrobiana con el tiempo, y a 63 °C perdió su capacidad inhibitoria a partir del tercer día. No se observó variación en la estabilidad del aceite de clavo a lo largo del tiempo en las distintas temperaturas de alma, The abusive use of antibiotics in aquaculture produces a negative impact on the environment, in addition to generating antibiotic-resistant pathogens. In this way, to minimize the effects of these chemotherapeutics on farmed fish, the environment and the consumers, other alternative therapies have been evaluated, including the use of plant extracts with antimicrobial capacity. The aim of this study was the evaluation of the antimicrobial potential of some natural substances as method of control of bacterial diseases in aquaculture. A first selection of substances was made based on their ability to inhibit three fish pathogens: Vibrio harveyi, Photobacterium damselae subsp. piscicida and Aeromonas hydrophila. The potencial toxicity of the substances was calculated by the observation of the decrease of the bioluminescence of Vibrio fischeri, being the clove oil the most toxic substance, with an effective concentration 50 (EC50) of 0.059 μL mL-1. Afterwards, the ability of the substances to interfere the mechanism of quorum sensing, by which some pathogenic bacteria coordinate the expression of virulence factors, was determined. Results showed that, except the lemongrass oil, all of the tested substances had the capacity to inhibit the quorum sensing. After these selective processes, garlic and clove oil were chosen to continue with the trials. Viability assays were carried out to see if they kept their antimicrobial properties after the extraction and storage processes at 63, 37, 22 and 4 °C during 1, 3 and 7 days. Garlic decreased its antimicrobial capacity over time, and at 63 °C it lost its inhibitory ability from the third day. There was no variation in the stability of the clove oil over time at different storage temperatures. Also garlic and clove oil were added to the feed diets of fishes, to check if in this mix they could lose their antimicrobial properties. Results showed that, at a concentration of 20 mg mL-1 of garlic, and 40, 20 and 10 μL mL-1 of clove oi

The article has two fold purpose; it proposes a revised technology acceptance model which includes usability dimensions and then tests revised model by measuring user acceptance of web-based transactional systems (WTS). Model was tested and validated through data obtained from 301 online users. The results suggest that the two important tenets, usefulness and ease of use have significant influence on intention to transact. Response time was found to have an effect on perceived usefulness. Accessibility and navigability had shown significant impact on perceived ease of use. Overall, results supported the proposed hypothetical model.

El conocimiento, prevención y tratamiento de las patologías existentes es posiblemente el factor más limitante en la actualidad para el engorde del lenguado (Solea senegalensis, Kaup 1858). Sin embargo, no hay evidencia de que ésta sea una especie más susceptible que otras a las infecciones bacterianas. Los actuales sistemas de producción intensiva suponen un estrés para los ejemplares en cultivo, ocasionando una menor eficiencia digestiva, una mayor susceptibilidad frente a patógenos potenciales y pérdidas económicas para la industria. Puesto que la producción en acuicultura depende, en buena medida, del estatus fisiológico de los peces, se hace preciso el empleo de piensos comerciales específicos y adecuados protocolos de cultivo que favorezcan el bienestar animal. La utilización de probióticos a nivel comercial en dieta (células microbianas con un efecto positivo para la salud del hospedador) es ya una herramienta eficaz para la mejora del metabolismo, reducción de deformidades y prevención de patologías en acuicultura de salmónidos

Probiotics are currently being supplemented to cultured fish due to their benefits for fish performance. Herein, we tested the health protection and nutritional effects of probiotic Shewanella putrefaciens (Pdp11 strain), both fresh and lyophilized cells, on Senegalese sole (Solea senegalensis) juveniles. Pdp11 was incorporated into fish feed at concentration of 109 cells g−1, and then provided to juvenile sole for 2 months. Growth rates were significantly higher in fish fed the fresh probiotic compared with fish fed the control diet. Growth of fish receiving lyophilized bacteria was not improved when compared with controls. Body compositions (protein, total lipids and fatty acids profile) were similar for each dietary treatment. At the end of the study, fish were challenged by intraperitoneal inoculation with a pathogenic strain of Photobacterium damselae subsp. piscicida. Relative percentages of survival (RPS) ranged between 25% and 43.8% for fish receiving both probiotic supplemented diets. Both fresh and lyophilized Pdp11 cells conferred protection against P. damselae subsp. piscicida. However, only fresh Pdp11 enhanced Senegal sole performance. These findings should be taken into account for industry purposes in which lyophilized Pdp11 might be easier to manage.

The effects of dietary administration of probiotic Pdp11, a bacterial probiotic strain from the Alteromonadaceae family, on growth and stress tolerance to high stocking density was analyzed in juvenile gilthead sea bream Sparus auratus. In the first trial, juvenile specimens were fed during 116 days with control feed or diets supplemented with Pdp11, and growth, serum immunological parameters as well as plasmatic, hepatic and muscular metabolic parameters were assessed. Growth performance improved in group receiving probiotic compared to control group. No differences were observed for the assessed immunological or metabolic parameters. In the second trial, specimens from both groups from the first experiment were submitted to the following conditions for 15 days: i) group fed with control food and either under low density (3 kg/m3), or high density (30 kg/m3) and ii) group fed with probiotic supplemented feed and either under low density, or high density. Our results indicated that administration of probiotic Pdp11 in the diet promoted growth and improved stress tolerance under high stocking density, suggesting its use will be beneficial for the aquaculture industry of this species.