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PubChem3D: a new resource for scientists
Evan E Bolton, Jie Chen, Sunghwan Kim, Lianyi Han, Siqian He, Wenyao Shi, Vahan Simonyan, Yan Sun, Paul A Thiessen, Jiyao Wang, Bo Yu, Jian Zhang, Stephen H Bryant
Journal of Cheminformatics , 2011, DOI: 10.1186/1758-2946-3-32
Abstract: PubChem generates a 3-D conformer model description for 92.3% of all records in the PubChem Compound database (when considering the parent compound of salts). Each of these conformer models is sampled to remove redundancy, guaranteeing a minimum (non-hydrogen atom pair-wise) RMSD between conformers. A diverse conformer ordering gives a maximal description of the conformational diversity of a molecule when only a subset of available conformers is used. A pre-computed search per compound record gives immediate access to a set of 3-D similar compounds (called "Similar Conformers") in PubChem and their respective superpositions. Systematic augmentation of PubChem resources to include a 3-D layer provides users with new capabilities to search, subset, visualize, analyze, and download data.A series of retrospective studies help to demonstrate important connections between chemical structures and their biological function that are not obvious using 2-D similarity but are readily apparent by 3-D similarity.The addition of PubChem3D to the existing contents of PubChem is a considerable achievement, given the scope, scale, and the fact that the resource is publicly accessible and free. With the ability to uncover latent structure-activity relationships of chemical structures, while complementing 2-D similarity analysis approaches, PubChem3D represents a new resource for scientists to exploit when exploring the biological annotations in PubChem.PubChem [1-4] (http://pubchem.ncbi.nlm.nih.gov webcite) is an open repository for small molecules and their experimental biological activities. The primary goal of PubChem is to be a public resource containing comprehensive information on the biological activities of small molecules. PubChem provides search, retrieval, visualization, analysis, and programmatic access tools in an effort to maximize the utility of contributed information. The PubChem3D project adds a new layer to this infrastructure. In the most basic sense, PubChem3D [5-
Redes de intercambio de información científica y académica entre los profesionales en el contexto de la Web 2.0 Networks for information exchange among scientists and scholars in the context of Web 2.0  [cached]
Sonia Santana Arroyo
ACIMED , 2010,
Abstract: Las redes sociales para intercambio de información entre científicos y académicos, concebidas para profundizar sus vínculos en el contexto actual de la Web 2.0, es el tema abordado en este artículo. Se caracterizan algunos de los principales sitios dise ados especialmente para las ciencias y la tecnología, tales como NatureNetwork, CTSciNeT, BiomedExpert y ResearchGate. Se muestran importantes aspectos a tener en cuenta durante el proceso de comunicación de los resultados científicos. Se describe la relación de las organizaciones de información, en todas sus variantes, con las redes de intercambio social, en un intento de lograr un mayor acercamiento y de estar presentes allí donde van sus usuarios reales y potenciales. Se advierte sobre el peligro de que las organizaciones de información equivoquen su rumbo ante las supuestas ventajas de muchas de las denominadas últimas tecnologías y su inclusión en otros tipos de redes cuya eficiencia queda por demostrar. Social networks for information exchange among scientists and scholars, designed to deepen their ties in the context of Web 2.0 is the issue addressed in this article. Some of the major sites designed especially for science and technology, such as NatureNetwork, CTSciNeT, BiomedExpert and ResearchGATE are featured. The article also shows important aspects to be considered during the process of communicating scientific results. It describes the relationship between information organizations, in all its forms, and networks of social exchange, in an attempt to be closer and more present where actual and potential users are. It warns about organizations that may overvalue the benefits of many so-called latest technologies and their inclusion in other types of networks whose effectiveness remains to be demonstrated.
Urolithiasis in Male Boiler Breeders  [PDF]
J.R. Moyle,R.F. Wideman,S.M. Whipple,D.E. Yoho
International Journal of Poultry Science , 2011,
Abstract: Mortality often is much higher in male than in female broiler breeders (36.2% vs. 11.1%), making it necessary to introduce additional males during the breeding cycle. While it is known that males perform better on low protein diets, they usually are fed the same diet as the hens in order to reduce feed transportation costs and eliminate the chance of the hens receiving the wrong feed. Hen diets are high in Calcium (Ca) which may be detrimental to male performance and may cause kidney damage as the males excrete the excess Ca. In an effort to understand the extent of kidney damage that occurs in male broiler breeders, 136 males that had been on commercial breeder hen diets for 41 or 42 wks were euthanized and their kidneys evaluated. Data collected included body weight, left and right kidney weights and the incidence of macroscopically visible uroliths within the ureters or ureteral branches. The bilateral symmetry of the two kidneys (heavy:light kidney weight ratio) was assessed as an indicator of subclinical kidney damage. The results revealed that only 55.6% of the males had kidneys that were bilaterally symmetrical (within 10% by weight). Left kidneys were significantly heavier than right kidneys (10.07 vs. 9.26 g, respectively) and the left kidney was larger in 76.3% of the birds. Uroliths were found in 7.4% (10/136) of the males. These results indicate that broiler breeder males fed high levels of Ca develop kidney asymmetry and urolithiasis, which can contribute to their high mortality levels.
Ranking scientists  [PDF]
S. N. Dorogovtsev,J. F. F. Mendes
Computer Science , 2015,
Abstract: Currently the ranking of scientists is based on the $h$-index, which is widely perceived as an imprecise and simplistic though still useful metric. We find that the $h$-index actually favours modestly performing researchers and propose a simple criterion for proper ranking.
Code Review For and By Scientists  [PDF]
Marian Petre,Greg Wilson
Computer Science , 2014,
Abstract: We describe two pilot studies of code review by and for scientists. Our principal findings are that scientists are enthusiastic, but need to be shown code review in action, and that just-in-time review of small code changes is more likely to succeed than large-scale end-of-work reviews.
Broiler breeders should not be reared on long photoperiods
PD Lewis, RM Gous
South African Journal of Animal Science , 2007,
Abstract: Sexual maturity is delayed and egg numbers are reduced when broiler breeders are reared on long photoperiods. However, this is the recommended procedure for rearing spring-hatched birds in non-lightproof buildings. Research at the University of KwaZulu-Natal has suggested that this advice may be incorrect, and that precocity is not a problem in control-fed broiler breeders reared on increasing daylengths. This trial compared the responses of four broiler breeder genotypes to a typical lighting programme advocated for birds in lightproof housing with the provision of 14-h photoperiods to 20 weeks and 16 h in lay. The long-day rearing resulted in a 26-d delay in sexual maturation, seven fewer eggs to 60 weeks, a 2.5-g increase in egg weight, less efficient feed conversion, heavier body weights at sexual maturity and throughout the laying period, and a higher incidence of mortality. It is concluded, therefore, that broiler breeders should not be reared on long photoperiods, even when hatched in the spring and kept in non-lightproof facilities, because of the adverse consequences of a delay in the dissipation of photorefractoriness.
Breeders’ work after cultivar development - the stage of recommendation
Luiz Carlos Federizzi,Sérgio Augusto Morais Carbonell,Marcelo Teixeira Pacheco,Itamar Cristiano Nava
Crop Breeding and Applied Biotechnology , 2012,
Abstract: The development of new cultivars is the ultimate goal of breeding programs and is the result of many years of hard work and dedication of breeders and their teams. An important part of the process, often neglected by geneticists, is the stage from recommendation to the production of breeder seed (post-breeding). This paper discusses the role of the breeder in the recommendation, registration, protection and marketing of new cultivars. The breeder’s active participation in all phases of post-breeding is fundamental to ensure that the cultivar reaches farmers quickly and can provide the benefits expected by society
Haemorrhagic enteritis seroconversion in turkey breeders: field observations  [cached]
Raffaella Ceruti,Marco Della Valentina,Luigi Gavazzi,Annalisa Venni
Italian Journal of Animal Science , 2010, DOI: 10.4081/ijas.2007.321
Abstract: Seroconversion to viral haemorrhagic enteritis (HE) was studied in seven flocks of turkey breeders (17.974 birds in total), after 20 weeks of the onset of egg production. They showed no clinical signs, and mortality rate was normal. However, the infection caused a drop in egg production lasting about five weeks (-2.32 eggs laid during this period), but had no effect on hatching parameters.
Persistence and Transmission Pattern of Avian Adenovirus-4 in Broiler Breeders  [PDF]
S. Ashraf,S. A. Malik,K. Naeem
Pakistan Journal of Biological Sciences , 2000,
Abstract: This study was undertaken to investigate the persistence of Avian Adenovirus-4 (AAV-4) in broiler breeders after the infection of Angara Disease (AD) and also to study its transmission pattern in the progeny. In the affected breeders the presence of AAV-4 was detected in organs of embryonated eggs and egg albumen derived from breeders at 30, 37 and 44 weeks of age, using Dot- ELISA. Shedding of the virus was found to be at its peak at the start of the laying period, decreasing successively thereafter. It has been proposed to vaccinate the breeders against AD to protect the progeny and eliminating the carriers so as to prevent the virus from circulating in the population.
Effect of Probiotic on Some Physiological Parameters in Broiler Breeders  [PDF]
Khalid H. Sultan,Saeb Y. Abdul- Rahman
International Journal of Poultry Science , 2011,
Abstract: The study was conducted to evaluate the effect of probiotic diet supplementation on some physiological parameters in Broiler Breeders. 30 Cobb Breeder hens were used (46 week aged), divided into 3 groups (10 hens each). The 1st group was reared on standard ration (control), the 2nd and the 3rd groups were given 10 and 20 gm of probiotic/kg ration for 4 weeks. The results revealed that the probiotic treatment causes a significant increase in LH and FSH serum levels (3rd group) and in T3 levels in (2nd and 3rd group) as compared with control group at p<0.05. Also the probiotic treatment causes a significant decrease in serum triglyceride levels and a significant increase in serum Uric acid level as compared with control. The above effects reflected in improvement of the egg weight, yolk weight and egg production % as compared with control. In conclusion, the probiotic supplementation of Broiler Breeders diet will improve the hormonal status and enhance the productivity.
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