106 research outputs found
Inversion dynamics in some population of an emerging vector of malaria Anopheles (Celia) subpictus Grassi (Diptera: Culicidae)
The present paper deals with the polytene chromosome inversion polymorphism based genomic characterization of Anopheles subpictus Grassi (Culicidae: Diptera) which has attained the status of an emerging vector of malaria in Srilanka, West Bengal and some coastal parts of India. The inversion data of the present population from Hoshairpur, Punjab (pop.A), India has also been compared with five other populations of this species worked out earlier in this laboratory so as to have a comprehensive assessment of inversion dynamics in this taxon. From the percentage frequency of inversions it was also evident that both rural and urban populations of An. subpictus had nearly similar inversion frequencies. In addition to these observations, it was interesting to note that irrespective of the number of individuals sacrificed, cells studied and the number of aberrations encountered from each population, inversions always constituted 50% of the total mutational index. On the basis of the present comparative data of inversion polymorphism, it is logical to suggest that, similar to âmeiotic driveâ and âmolecular driveâ there is also a type of âinversion driveâ which constantly changes population genomics to augment competitive fitness of the species. Our recent studies on the r DNA ITS2 sequence variations also suggest this contension
RAPD-PCR based genomic characterization of two populations of Culex quinquefasciatus (Diptera : Culicidae)
The present paper deals with the RAPD-PCR based genomic characterization of Culex quinquefasciatus Say which is a major vector of filariasis in several parts of the Indian subcontinent. One population of the test organism used in the study was procured from Goa (pop.A) while the other (pop.B) was collected from a village Nadasahib (20 kms from Chandigarh). The RAPD-PCR amplification of whole body homogenate of freshly hatched individual specimens was carried out by using three random primers: primer I- 5â- GTCCCGACGA â 3â; primer II- 5ââ TGATCCCTGG â 3â and primer III- 5â- GTGACGTAGG â 3â. Primer I produced 5 distinct bands from the DNA of pop. A, whose base composition ranged from 200-1000 bp. Likewise, 7 bands ranging from 130-750 bp and 4 bands ranging from 270-950 bp were generated with primers II and III respectively. In case of pop.B, a total of 8 bands ranging from 200-1000 bp were generated with primer I. Similarly, a total of 6 bands ranging from 250-900 bp with primer II and 4 bands ranging from 180-950 bp with primer III were produced. Based on the bandsharing coefficient and the application of Nearest Neighbour Joining (NJ) analysis it was found that primer Iwas more suitable for detecting genomic differences at the species and generic levels while primer II was ideal for detecting variations in the number of bp in RAPD generated bands among different populations of Cx. quinquefasciatus
Chiral Supergravity
We study the linearized approximation of N=1 topologically massive
supergravity around AdS3. Linearized gravitino fields are explicitly
constructed. For appropriate boundary conditions, the conserved charges
demonstrate chiral behavior, so that chiral gravity can be consistently
extended to chiral supergravity.Comment: 30 page
Black Hole Microstates and Attractor Without Supersymmetry
Due to the attractor mechanism, the entropy of an extremal black hole does
not vary continuously as we vary the asymptotic values of various moduli
fields. Using this fact we argue that the entropy of an extremal black hole in
string theory, calculated for a range of values of the asymptotic moduli for
which the microscopic theory is strongly coupled, should match the statistical
entropy of the same system calculated for a range of values of the asymptotic
moduli for which the microscopic theory is weakly coupled. This argument does
not rely on supersymmetry and applies equally well to nonsupersymmetric
extremal black holes. We discuss several examples which support this argument
and also several caveats which could invalidate this argument.Comment: 50 pages; references adde
Moduli and (un)attractor black hole thermodynamics
We investigate four-dimensional spherically symmetric black hole solutions in
gravity theories with massless, neutral scalars non-minimally coupled to gauge
fields. In the non-extremal case, we explicitly show that, under the variation
of the moduli, the scalar charges appear in the first law of black hole
thermodynamics. In the extremal limit, the near horizon geometry is
and the entropy does not depend on the values of moduli at
infinity. We discuss the attractor behaviour by using Sen's entropy function
formalism as well as the effective potential approach and their relation with
the results previously obtained through special geometry method. We also argue
that the attractor mechanism is at the basis of the matching between the
microscopic and macroscopic entropies for the extremal non-BPS Kaluza-Klein
black hole.Comment: 36 pages, no figures, V2: minor changes, misprints corrected,
expanded references; V3: sections 4.3 and 4.5 added; V4: minor changes,
matches the published versio
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Coordinating Tissue Regeneration Through Transforming Growth Factorâ Ă² Activated Kinase 1 Inactivation and Reactivation
Aberrant wound healing presents as inappropriate or insufficient tissue formation. Using a model of musculoskeletal injury, we demonstrate that loss of transforming growth factorâ Ă² activated kinase 1 (TAK1) signaling reduces inappropriate tissue formation (heterotopic ossification) through reduced cellular differentiation. Upon identifying increased proliferation with loss of TAK1 signaling, we considered a regenerative approach to address insufficient tissue production through coordinated inactivation of TAK1 to promote cellular proliferation, followed by reactivation to elicit differentiation and extracellular matrix production. Although the current regenerative medicine paradigm is centered on the effects of drug treatment (â drug onâ ), the impact of drug withdrawal (â drug offâ ) implicit in these regimens is unknown. Because current TAK1 inhibitors are unable to phenocopy genetic Tak1 loss, we introduce the dualâ inducible COmbinational Sequential Inversion ENgineering (COSIEN) mouse model. The COSIEN mouse model, which allows us to study the response to targeted drug treatment (â drug onâ ) and subsequent withdrawal (â drug offâ ) through genetic modification, was used here to inactivate and reactivate Tak1 with the purpose of augmenting tissue regeneration in a calvarial defect model. Our study reveals the importance of both the â drug onâ (Creâ mediated inactivation) and â drug offâ (Flpâ mediated reactivation) states during regenerative therapy using a mouse model with broad utility to study targeted therapies for disease. Stem Cells 2019;37:766â 778Manipulating transforming growth factor Ă²â activated kinase 1 for cell and scaffold free tissue regeneration using a dualâ inducible Combinational Sequential Inversion Engineering mouse model.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149573/1/stem2991_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149573/2/stem2991.pd
Determinants of outcomes following surgery for type A acute aortic dissection: the UK National Adult Cardiac Surgical Audit
Aimsâ
Operability of type A acute aortic dissections (TAAAD) is currently based on non-standardized decision-making process, and it lacks a disease-specific risk evaluation model that can predict mortality. We investigated patient, intraoperative data, surgeon, and centre-related variables for patients who underwent TAAAD in the UK.
Methods and results
We identified 4203 patients undergoing TAAAD surgery in the UK (2009â18), who were enrolled into the UK National Adult Cardiac Surgical Audit dataset. The primary outcome was operative mortality. A multivariable logistic regression analysis was performed with fast backward elimination of variables and the bootstrap-based optimism-correction was adopted to assess model performance. Variation related to hospital or surgeon effects were quantified by a generalized mixed linear model and risk-adjusted funnel plots by displaying the individual standardized mortality ratio against expected deaths. Final variables retained in the model were: age [odds ratio (OR) 1.02, 95% confidence interval (CI) 1.02â1.03; Pâ<â0.001]; malperfusion (OR 1.79, 95% CI 1.51â2.12; Pâ<â0.001); left ventricular ejection fraction (moderate: OR 1.40, 95% CI 1.14â1.71; Pâ=â0.001; poor: OR 2.83, 95% CI 1.90â4.21; Pâ<â0.001); previous cardiac surgery (OR 2.29, 95% CI 1.71â3.07; Pâ<â0.001); preoperative mechanical ventilation (OR 2.76, 95% CI 2.00â3.80; Pâ<â0.001); preoperative resuscitation (OR 3.36, 95% CI 1.14â9.87; Pâ=â0.028); and concomitant coronary artery bypass grafting (OR 2.29, 95% CI 1.86â2.83; Pâ<â0.001). We found a significant inverse relationship between surgeons but not centre annual volume with outcomes.
Conclusionsâ
Patient characteristics, intraoperative factors, cardiac centre, and high-volume surgeons are strong determinants of outcomes following TAAAD surgery. These findings may help refining clinical decision-making, supporting patient counselling and be used by policy makers for quality assurance and service provision improvement
ESolvent-free, enzyme-catalyzed biodiesel production from mango, neem, and shea oils via response surface methodology
Mango, neem and shea kernels produce non-conventional oils whose potentials are not fully exploited. To give an added value to these oils, they were transesterified into biodiesel in a solvent-free system using immobilized enzyme lipozyme from Mucor miehei. The Doehlert experimental design was used to evaluate the methyl ester (ME) yields as influenced by enzyme concentrationâEC, temperatureâT, added water contentâAWC, and reaction timeâRT. Biodiesel yields were quantified by (1)H NMR spectroscopy and subsequently modeled by a second order polynomial equation with interactions. Lipozyme enzymes were more tolerant to high temperatures in neem and shea oils reaction media compared to that of mango oil. The optimum reaction conditions EC, T, AWC, and RT assuring near complete conversion were as follows: mango oil 7.25 %, 36.6 °C, 10.9 %, 36.4 h; neem oil EC = 7.19 %, T = 45.7 °C, AWC = 8.43 %, RT = 25.08 h; and shea oil EC = 4.43 %, T = 45.65 °C, AWC = 6.21 % and RT = 25.08 h. Validation experiments of these optimum conditions gave ME yields of 98.1 ¹ 1.0, 98.5 ¹ 1.6 and 99.3 ¹ 0.4 % for mango, neem and shea oils, respectively, which all met ASTM biodiesel standards
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