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201.
Following the injury and disability of the dominant male, the home range of a group of rhesus in a rural habitat in Aligarh district was significantly reduced from 40 acres to less than 10 acres. Throughout this injury and prior to his death, the male maintained his dominance in reference to a peripheral male who frequently attempted to enter the group. Upon the death of the dominant male, group leadership and dominance was assumed by a young subdominant male within the group and the peripheral male still remained outside the group. These observations indicate a strong social tradition in the maintenance of dominance within this wild rhesus group, and they emphasize the role of the dominant male in maintaining home range.This work was begun under grants from the U.S. Educational Foundation in India, and the U.S. Public Health Service (RG 6262 and RG-6262 S1), and has been continued since 1961 under the auspices of the Johns Hopkins Center for Medical Research and Training supported by USPHS Grant GM 11326. We are indebted to Mr. Mirza A. Beg and Dr. M. Farooq Siddiqi for assistance with field observations, and to Dr. F. B. Bang for administrative support. 相似文献
202.
Therapeutic bacteriophages are emerging as a potential alternative to antibiotics and synergistic treatment of antimicrobial-resistant infections. This is reflected by their use in an increasing number of recent clinical trials. Many more therapeutic bacteriophage is being investigated in preclinical research and due to the bespoke nature of these products with respect to their limited infection spectrum, translation to the clinic requires combined understanding of the biology underpinning the bioprocess and how this can be optimized and streamlined for efficient methods of scalable manufacture. Bacteriophage research is currently limited to laboratory scale studies ranging from 1–20 ml, emerging therapies include bacteriophage cocktails to increase the spectrum of infectivity and require multiple large-scale bioreactors (up to 50 L) containing different bacteriophage–bacterial host reactions. Scaling bioprocesses from the milliliter scale to multi-liter large-scale bioreactors is challenging in itself, but performing this for individual phage-host bioprocesses to facilitate reliable and robust manufacture of phage cocktails increases the complexity. This study used a full factorial design of experiments approach to explore key process input variables (temperature, time of infection, multiplicity of infection, agitation) for their influence on key process outputs (bacteriophage yield, infection kinetics) for two bacteriophage–bacterial host bioprocesses (T4 – Escherichia coli; Phage K – Staphylococcus aureus). The research aimed to determine common input variables that positively influence output yield and found that the temperature at the point of infection had the greatest influence on bacteriophage yield for both bioprocesses. The study also aimed to develop a scaled down shake-flask model to enable rapid optimization of bacteriophage batch bioprocessing and translate the bioprocess into a scale-up model with a 3 L working volume in stirred tank bioreactors. The optimization performed in the shake flask model achieved a 550-fold increase in bacteriophage yield and these improvements successfully translated to the large-scale cultures. 相似文献
203.
Fu YH Campioli M Demarée G Deckmyn A Hamdi R Janssens IA Deckmyn G 《International journal of biometeorology》2012,56(1):153-164
Numerous phenology models developed to predict the budburst date of trees have been merged into one Unified model (Chuine,
2000, J. Theor. Biol. 207, 337–347). In this study, we tested a simplified version of the Unified model (Unichill model) on
six woody species. Budburst and temperature data were available for five sites across Belgium from 1957 to 1995. We calibrated
the Unichill model using a Bayesian calibration procedure, which reduced the uncertainty of the parameter coefficients and
quantified the prediction uncertainty. The model performance differed among species. For two species (chestnut and black locust),
the model showed good performance when tested against independent data not used for calibration. For the four other species
(beech, oak, birch, ash), the model performed poorly. Model performance improved substantially for most species when using
site-specific parameter coefficients instead of across-site parameter coefficients. This suggested that budburst is influenced
by local environment and/or genetic differences among populations. Chestnut, black locust and birch were found to be temperature-driven
species, and we therefore analyzed the sensitivity of budburst date to forcing temperature in those three species. Model results
showed that budburst advanced with increasing temperature for 1–3 days °C−1, which agreed with the observed trends. In synthesis, our results suggest that the Unichill model can be successfully applied
to chestnut and black locust (with both across-site and site-specific calibration) and to birch (with site-specific calibration).
For other species, temperature is not the only determinant of budburst and additional influencing factors will need to be
included in the model. 相似文献
204.
Elena Costariol Marco Rotondi Arman Amini Christopher J. Hewitt Alvin W. Nienow Thomas R.J. Heathman Martina Micheletti Qasim A. Rafiq 《Biotechnology and bioengineering》2019,116(10):2488-2502
Advanced cell and gene therapies such as chimeric antigen receptor T-cell immunotherapies (CAR-T), present a novel therapeutic modality for the treatment of acute and chronic conditions including acute lymphoblastic leukemia and non-Hodgkin lymphoma. However, the development of such immunotherapies requires the manufacture of large numbers of T-cells, which remains a major translational and commercial bottleneck due to the manual, small-scale, and often static culturing systems used for their production. Such systems are used because there is an unsubstantiated concern that primary T-cells are shear sensitive, or prefer static conditions, and therefore do not grow as effectively in more scalable, agitated systems, such as stirred-tank bioreactors, as compared with T-flasks and culture bags. In this study, we demonstrate that not only T-cells can be cultivated in an automated stirred-tank bioreactor system (ambr® 250), but that their growth is consistently and significantly better than that in T-flask static culture, with equivalent cell quality. Moreover, we demonstrate that at progressively higher agitation rates over the range studied here, and thereby, higher specific power inputs (P/M W kg−1), the higher the final viable T-cell density; that is, a cell density of 4.65 ± 0.24 × 106 viable cells ml−1 obtained at the highest P/M of 74 × 10−4 W kg−1 in comparison with 0.91 ± 0.07 × 106 viable cells ml−1 at the lowest P/M of 3.1 × 10−4 W kg−1. We posit that this improvement is due to the inability at the lower agitation rates to effectively suspend the Dynabeads®, which are required to activate the T-cells; and that contact between them is improved at the higher agitation rates. Importantly, from the data obtained, there is no indication that T-cells prefer being grown under static conditions or are sensitive to fluid dynamic stresses within a stirred-tank bioreactor system at the agitation speeds investigated. Indeed, the opposite has proven to be the case, whereby, the cells grow better under higher agitation speeds while maintaining their quality. This study is the first demonstration of primary T-cell ex vivo manufacture activated by Dynabeads® in an automated stirred-tank bioreactor system such as the ambr® 250 and the findings have the potential to be applied to multiple other cell candidates for advanced therapy applications. 相似文献
205.
Wali Khan Naseem Rafiq Zubia Masood Munawar Salim Ahmed Hafeez Ur Rahman Muhammad Kabir Rukhsana Ghaffar Attiqa Naz Muhammad Ishaq Ali Shah 《Saudi Journal of Biological Sciences》2021,28(4):2285-2290
Present study was conducted to get information on helminth parasites of zoonotic importance among the black rats of district Swat, Pakistan. Two hundred and sixty nine rats were captured from agricultural ecosystem of the district using live captured traps from 2011 to 2013. Captured rats were anesthetized and surveyed for the presence of ectoparasites, then were carefully dissected for investigation of endoparsites. Helminth parasites of 8 species were identified. Presence of parasite was noticed in 23.7% of sampled rats. The infection rates of sampled rats was given in order of their infectivity as Syphacia obvelata 13(4.83%), Aspiculuris tetraptera 13(4.83%), Heterakis spumosa 12 (4.46%), Hymenolepis spp. 9(3.34%), H.diminuta 8(2.97%), Hymenolepis fusa 4(1.48%), Lutziella microacetabularae 4(1.48%) and Lutziella spp. 1 (0.37%). No significant difference (P < 0.4289) was found in prevalence of parasites among areas, crops, crop stages and sex of the host while adult rats were found more infected than sub-adults. S. obvelata and A. tetraptera were the most common species of helminths while Lutziella sp., 1 (0.37%) was found only in one host. Rattus rattus (the black rat) was regarded as the host of helminth parasites of zoonotic importance, therefore the hidden health hazards of this rodent species needed to be considered to prevent infectivity of humans. Current study was concluded that Rattus rattus harbored a wide variety of helminth parasites which shows a hidden risk to inhabitants of the region. Monitoring rats’ population in settle areas and educating the local community about the risk of rat borne parasitic diseases transmission through rats appears to be absolutely essential. 相似文献
206.
207.
Foliage and tuber fresh matter and chlorophyll content in cvs. Atom alue, Multa, Kufri, Desiree and Patrones were decreased with the increase in soil acidity. However, tuberization was enhanced at pH 5.5 and decreased significantly at pH 4.5 in all cultivars tested. At pH 4.5 the specific mass of all the cultivars was slightly increased. The highest content of reducing sugars and proteins was found at pH 5.5. No definite pattern was observed in total glycoalkaloids content under different acidic range. 相似文献