Closely related species of Drosophila tend to have similar genome sizes. The strong imbalance in favor of small deletions relative to insertions implies that the unconstrained DNA in Drosophila is ...unlikely to be passively inherited from even closely related ancestors, and yet most DNA in Drosophila genomes is intergenic and potentially unconstrained. In an attempt to investigate the maintenance of this intergenic DNA, we studied the evolution of an intergenic locus on the fourth chromosome of the Drosophila melanogaster genome. This 1.2-kb locus is marked by two distinct, large insertion events: a nuclear transposition of a mitochondrial sequence and a transposition of a nonautonomous DNA transposon DNAREP1_DM. Because we could trace the evolutionary histories of these sequences, we were able to reconstruct the length evolution of this region in some detail. We sequenced this locus in all four species of the D. melanogaster species complex: D. melanogaster, D. simulans, D. sechellia, and D. mauritiana. Although this locus is similar in size in these four species, less than 10% of the sequence from the most recent common ancestor remains in D. melanogaster and all of its sister species. This region appears to have increased in size through several distinct insertions in the ancestor of the D. melanogaster species complex and has been shrinking since the split of these lineages. In addition, we found no evidence suggesting that the size of this locus has been maintained over evolutionary time; these results are consistent with the model of a dynamic equilibrium between persistent DNA loss through small deletions and more sporadic DNA gain through less frequent but longer insertions. The apparent stability of genome size in Drosophila may belie very rapid sequence turnover at intergenic loci.
Cyanobacteria have the potential to become next-generation cell factories due to their ability to use CO
, light and inorganic nutrients to produce a range of biomolecules of commercial interest.
...UTEX 2973, in particular, is a fast-growing, genetically tractable, cyanobacterium that has garnered attention as a potential biotechnological chassis. To establish this unique strain as a host for heterologous protein production, we aimed to demonstrate expression and secretion of the industrially relevant
AA10A, a lytic polysaccharide monooxygenase from the Gram-positive bacterium
Two variations of
AA10A were successfully expressed in
UTEX 2973: One containing the native N-terminal, Sec-targeted, signal peptide and a second with a Tat-targeted signal peptide from the
trimethylamine-
-oxide reductase (TorA). Although the TorA signal peptide correctly targeted the protein to the plasma membrane, the majority of the TorA-
AA10A was found unprocessed in the plasma membrane with a small fraction of the mature protein ultimately translocated to the periplasm. The native Sec signal peptide allowed for efficient secretion of
AA10A into the medium with virtually no protein being found in the cytosol, plasma membrane or periplasm.
AA10A was demonstrated to be correctly cleaved and active on the model substrate phosphoric acid swollen cellulose. Additionally, expression and secretion only had a minor impact on cell growth. The secretion yield was estimated at 779 ± 40 µg L
based on densitometric analysis. To our knowledge, this is the highest secretion yield ever registered in cyanobacteria.
We have shown for the first time high-titer expression and secretion of an industrially relevant and catalytically active enzyme in
UTEX 2973. This proof-of-concept study will be valuable for the development of novel and sustainable applications in the fields of bioremediation and biocatalysis.
Resource-poor farmers in India cultivate upland rice as a subsistence crop in poor soil with minimum inputs, often applying little or no fertilizer and controlling weeds by hand. Consequently, upland ...rice yields are very low. In our study, the response to management intensification of fertilizer application at rates of 40 N
ha
−1, 13 P
ha
−1, and 16.7
K
ha
−1 and two weed control treatments as compared with no fertilizer, and one hand weeding practice commonly followed by farmers in rainfed upland areas was examined with a large set of advanced breeding lines and adapted upland varieties tested over 3 years in multi-location trials. Highly significant genotype
×
environment interaction was observed in combined analyses across environments, leading to sub-grouping of sites into the high-yielding or favorable and low-yielding or unfavorable upland environment groups. A significant effect of management regime was observed. Averaged over 15 environments, the moderate-input treatment out-yielded the low-input treatment by nearly 65% or 0.8
t
ha
−1 under favorable environments and by nearly 48% (0.3
t
ha
−1) in unfavorable environments. A significant genotype effect and genotype
×
input management interaction for yield at favorable sites was observed. However, the same was not significant at unfavorable sites. Varietal differences were relatively small at unfavorable sites across input levels. The heritability estimates for grain yield were moderately high in both moderate- and low-input conditions in favorable environments. The genetic correlation between yields in moderate- and low-input conditions was high in both favorable and unfavorable environments. The study indicated that improved varieties performed well relative to landraces under low-input management. Improved varieties along with modestly intensified management offer an attractive option to increase the productivity of rainfed upland environments. For both favorable and unfavorable environments, indirect selection under moderate-input conditions was less efficient than direct selection for grain yield in low-input conditions, indicating upland breeding programs to adopt selection for grain yield under both moderate- and low-input conditions.
Demand for infrastructure development in coastal regions where the subsurface is often composed of soft clays, results from the desire for rapid industrialization. The frequently encountered coastal ...soil conditions often call for suitable ground improvement and modification techniques to prepare soft deposits for foundation construction. For appropriate site improvement, several engineering soil properties are desired which require expensive and time consuming field and laboratory testing. Under such circumstances, empirical correlations based on routinely determined soil properties would be very useful and economical in planning of the project. With this as a goal, undisturbed samples from three on-shore and off-shore sites of the coastal regions in India, where major infrastructure projects are being executed, were collected. These samples were tested for physical, chemical, mineralogical and geotechnical characteristics. In addition, shear wave velocity of specimens of these soils was determined by using bender elements. Based on this data, empirical correlations between void ratio, compression index and undrained shear strength with shear wave velocity of clays were developed. Because shear wave velocity can be easily determined in the laboratory, these correlations are found to be valuable for preliminary planning of the project. The utility of these correlations for preliminary characterization of the soft soil has also been demonstrated.
A detailed description of the assemblage of
Miogypsina
(
Lepidosemicyclina
)
bifida
Rutten from the sub-surface Mumbai Offshore is presented by carrying out biometric studies on nineteen equatorial ...sections. The mean V is 47.2 and the mean DI 212μm. The mean DII is 272.35μm and the mean ε 341.76μm. The larger spire has notational value in the range 4.1/2 to 7.1/2 and the smaller spire 1.1/2 to 3.1/2. The species is recorded to be occurring below
M. (L.) excentrica
Tan Sin Hok. In terms of the planktonic zonation, it pertains to the planktonic Zone N6 (Burdigalian). This is the first detailed study of
M.(L.) bifida
Rutten from India. The foraminifer,
M.(L.) bifida
Rutten, recorded from the L-III, a major producing reservoir of Mumbai High field is found in association with
Lepidocyclina
sp.,
Sphaerogypsina
sp.,
Operculina
sp.,
Amphistegina
sp.,
Elphidium
sp. and
Cibicides
sp. along with Bryozoa. The assemblage, recorded from limestone, indicates a shallow inner neritic paleoenvironment (bathymetry 15-20 meters) of deposition.
Background Therapy for chronic atrial fibrillation (AF) focuses on rate versus rhythm control, but little is known about the effects of common therapeutic interventions on exercise tolerance in AF. ...Methods Six hundred fifty-five patients with chronic AF underwent maximal exercise testing at baseline and 8 weeks, 6 months, and 1 year after randomization to sotalol, amiodarone, or placebo therapy and attempted direct current cardioversion. Analyses of baseline determinants of exercise capacity, predictors of change in exercise capacity at 6 months and 1 year, and the short- and long-term effects of cardioversion on exercise capacity were made. Results Age, obesity, and presence of symptoms accompanying AF were inversely associated with baseline exercise capacity, but these factors accounted for only 10% of the variance in exercise capacity. Patients most likely to benefit from cardioversion were those most limited initially, younger, not obese or hypertensive, and with an uncontrolled ventricular rate at baseline. Conversion to sinus rhythm (SR) resulted in significant reductions in resting (≈25 beat/min) and peak exercise (≈40 beat/min) heart rates at 6 months and 1 year ( P < .001). Successful cardioversion improved exercise capacity by 15% at 8 weeks, and these improvements were maintained throughout the year. This improvement was observed both among those who maintained SR and those with intermittent AF. Conclusion Cardioversion resulted in a sustained improvement in exercise capacity over the course of 1 year, and this improvement was similar between those in SR and those with SR and recurrent AF. Patients most likely to improve with treatment tended to be younger and nonobese and have the greatest limitations initially.
Colloidal carbon spheres were synthesized by the carbonization of squalane, a nonvolatile hydrocarbon solvent, in supercritical carbon dioxide. Precise pressure modulation of the fluid medium led to ...size controlled growth of carbon spheres ranging from 300 to 1500 nm in diameter. This unique synthetic approach of carbonizing a hydrocarbon suspension in supercritical fluid is found to suppress any particle aggregation, resulting in excellent sphere monodispersity. Core–shell hybrid structures of C–Ge were subsequently formed by inducing the growth of 10–40 nm sized germanium nanocrystals from the spheres in a hierarchical bottom-up approach. Extensive characterization of the spheres and nanocrystals was conducted using transmission and scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman, and thermogravametric analysis. Assemblies of nanocrystal modified carbon colloids impart outstanding superhydrophobic properties due to the combined nano- and microstructuring of the particle arrays.
Introduction: The Anterior Cruciate Ligament (ACL) is a very commonly injured ligament of knee. Several physical examination tests are performed for evaluating ACL stability. The Lachman, ...pivot-shift, and anterior drawer tests are commonly performed for evaluating the knee laxity. Aim: To compare Lever sign test with anterior drawer test and Lachman test in case of ACL tear, and to assess preanaesthesia and postanaesthesia variability in tests results. Materials and Methods: This prospective cohort study was conducted at Government Medical College, Kathua, Jammu, India, from October 2018 till September 2019. Total 50 patients were included (age group 18-60 years) with symptomatic ACL tear requiring diagnostic arthroscopy or repair. Three tests Lever sign test, anterior drawer test and Lachman test were performed preanaesthesia and postanaesthesia and findings were recorded. Sensitivity and specificity was calculated preanaesthesia and postanaesthesia. Statistical analysis was done using Statistical Package for Social Sciences (SPSS) version 21.0. The p-value ≤0.05 was considered statistically significant. Results: Total 50 patients were evaluated and analysed including 60% males (n=30) and 40% females (n=20). The mean age of the patients was 34.5±2.6 years. Sensitivity, specificity, Positive Predictive Value (PPV), Negative Predictive Values (NPV) and diagnostic accuracy of anterior drawer test preanaesthesia were 83%, 87%, 97%, 50%, and 84%, respectively, and postanaesthesia were 88%, 87%, 97%, 58%, and 88%; for Lachman test preanaesthesia were 88%, 87%, 97%, 58%, and 88%, respectively, and postanaesthesia were 90%, 87%, 97%, 63%, and 90%; and for Lever sign test preanaesthesia were 85%, 88%, 100%, 57%, and 88%, and postanaesthesia were 88%, 100%, 100%, 61%, and 90%, respectively. There was no significant difference in the diagnostic accuracy of the three tests while comparing for preanaesthesia and postanaesthesia or for individual tests (p>0.05). Conclusion: The lever test showed high specificity, but comparable diagnostic accuracy in the detection of ACL tears in comparison to anterior drawer test and Lachman test. All the tests hold equal importance for diagnosing ACL tears before and after anaesthesia.
Hexamethylenetetramine (HA) or hexamine (or urotropin) have a moderate inhibitive effect on the corrosion of mild steel in concentrated acid solution (3N) but have a negligible effect in very dilute ...solutions (N/200) of the acid. Incorporation of Cu
2+, As
3+, Sb
3+ and Sn
2+ with HA improves its performance, which is synergistic in nature. These additives (except As
3+), however, exhibit an antagonistic effect when tested in dilute acid solutions. Cu
2+ and As
3+ have the most pronounced effect in 3N acid solution. In N/200 HCl solution, the antagonistic effect is a maximum in the case of Sb
3+ followed by Sn
2+ and Cu
2+ cations. Weight-loss, electrochemical polarization and zeta potential measurements are performed to understand the mechanism of action of these inhibitors. The positive role played by the cations on the inhibitive performance of HA is due to the formation of anionic complexes with the chloride ions of the acid solution. These anions replace the adsorbed chloride ion from the metal-electrolyte interface owing to their higher affinity toward the interface and help the protonized molecule of HA to be adsorbed more strongly at the interface. Accumulation of FeCl
3 in concentrated acid solution lowers the performance of HA to a greater extent (about 100 times) than HA blended with Cu
2+. The latter composition also has a substantially stronger inhibitive role on hydrogen absorption by the steel than the former one.
▶ Ample variability for Fe, Zn, Ca, protein contents and agronomic traits. ▶ Identified promising accessions for high Fe, Zn, Ca and protein and grain yield. ▶ Identified diverse grain ...nutrient-specific accessions to study inheritance. ▶ Contrasting accessions to map nutrient traits. ▶ Diverse accessions to breed broad based nutrient-rich high yielding cultivars.
Finger millet is a promising source of micronutrients and protein besides energy and can contribute to the alleviation of iron (Fe), zinc (Zn) and protein malnutrition affecting women and preschool children in African and south-east Asian countries. The most cost effective approach for mitigating micronutrient and protein malnutrition is to introduce staple crop cultivars selected and/or bred for Fe, Zn and protein dense grain. Breeding finger millet for enhanced grain nutrients is still in its infancy. Analysis, detection and exploitation of the existing variability among the germplasm accessions are the initial steps in breeding micronutrient and protein-dense finger millet cultivars. Evaluation of finger millet core collection for grain nutrients and agronomic traits revealed a substantial genetic variability for grain Fe, Zn, calcium (Ca) and protein contents. The accessions rich in nutrient contents were identified and their agronomic diversity assessed. The accessions rich in Zn content have significantly higher grain yield potential than those rich in Fe and protein content. Grain nutrient-specific accessions and those contrasting for nutrient contents were identified for use in the strategic research and cultivar development in finger millet.
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