Context. It is well known that the polarity of the Sun’s magnetic field reverses or flips around the maximum of each 11 year solar cycle. This is commonly known as polar field reversal and plays a ...key role in deciding the polar field strength at the end of a cycle, which is crucial for the prediction of the upcoming cycle. Aims. We aim to investigate solar polar fields during cycle 24, using measurements of solar magnetic fields in the latitude range 55°–90° and 78°–90°, to report a prolonged and unusual hemispheric asymmetry in the polar field reversal pattern in solar cycle 24. Methods. This study was carried out using medium resolution line-of-sight synoptic magnetograms from the magnetic database of the National Solar Observatory at Kitt Peak (NSO/KP), USA for the period between February 1975 and October 2017, covering solar cycles 21–24 and high-resolution line-of-sight synoptic magnetograms from the Michaelson Doppler Imager instrument onboard the Solar Heliospheric Observatory. Synoptic magnetograms using radial measurements from the Heliospheric Magnetic Imager instrument onboard the Solar Dynamics Observatory, covering solar cycle 23 and 24, were also used. Results. We show that the southern solar hemisphere unambiguously reversed polarity in mid-2013 while the reversal in the field in the northern solar hemisphere started as early as June 2012, was followed by a sustained period of near-zero field strength lasting until the end of 2014, after which the field began to show a clear rise from its near-zero value. While this study compliments a similar study carried out using microwave brightness measurements which claimed that the field reversal process in cycle 24 was completed by the end of 2015, our results show that the field reversal in cycle 24 was completed earlier that is, in late 2014. Signatures of this unusual field reversal pattern were also clearly identifiable in the solar wind, using our observations of interplanetary scintillation at 327 MHz which supported our magnetic field observations and confirmed that the field reversal process was completed at the end of 2014.
Various direct and indirect environmental constraints have an impact on livestock performance. The physiological parameters, such as rectal temperature, heart rate, and respiratory rate, are the ...primary indicators of thermal stress. Under a stressed environment temperature humidity index (THI) had established as a vital measurement to identify the thermal stress in livestock. THI in association with climatic variations can define the environmental effect as stressful or comfortable for livestock. Goats are small ruminants that adapt to a wide range of ecological variations due to their anatomical and physiological characteristics. However, the productivity of animals declines at the individual level during thermal stress. Stress tolerance can be determined through genetic studies associated with at the cellular level using physiological as well as molecular approaches. Information on genetic association with thermal stress in goats is scanty, this severely affects their survival and hence productivity of livestock. The ever-increasing demand for food across the globe needs deciphering novel molecular markers as well as stress indicators that play a vital role in livestock improvement. This review represents an analysis of current knowledge of phenotypic differences during thermal stress and signifies the importance of physiological responses and their association at the cellular level in goats. The regulation of vital genes associated with thermal stress such as Aquaporins (AQP 0, 1, 2, 4, 5, 6, 8), aquaglyceroporins (AQP3, 7, 9, and 10) and super-aquaporins (AQP 11, 12); BAX inhibitors such as PERK (PKR like ER kinase), IRE 1(inositol-requiring-1); Redox regulating genes such as NOX; Transport of Na+ and K+ such as ATPase (ATP1A1) and several heat shock proteins have been implicated in heat-stress related adaptations have been elucidated. As these changes have a significant impact on production performance as well as on livestock productivity. Such efforts may help in the development of molecular markers and will assist the breeders to develop heat-tolerant goats with improved productivity.
•Heat stress is a major issue in livestock, affecting animal performance and hampering global production performance.•The key indicators of thermal stress in goats include physiological responses and other factors such as reduced growth, reduced milk production and reduced reproductive efficiency.•The importance of heat stress-tolerant and susceptible phenotypes, as well as their association with genetic markers and genetic analysis.•The genetic markers provide significant insights at the cellular level.•Such efforts may assist the breeders in the future to breed goats with improved productivity and survival under harsh climatic conditions.
In present study, the hepatoprotective activity of ethanolic and aqueous extracts of
Momordica dioica Roxb. leaves were evaluated against carbon tetrachloride (CCl
4) induced hepatic damage in rats. ...The extracts at dose of 200
mg/kg were administered orally once daily. The substantially elevated serum enzymatic levels of serum glutamate oxaloacetate transaminase (AST), serum glutamate pyruvate transaminase (ALT), serum alkaline phosphatase (SALP) and total bilirubin were restored towards normalization significantly by the extracts. Silymarin was used as standard reference and exhibited significant hepatoprotective activity against carbon tetrachloride induced haptotoxicity in rats. The biochemical observations were supplemented with histopathological examination of rat liver sections. The results of this study strongly indicate that
Momordica dioica Roxb. leaves have potent hepatoprotective action against carbon tetrachloride induced hepatic damage in rats. Ethanolic extract was found more potent hepatoprotective. Meanwhile, in vivo antioxidant and free radical scavenging activities were also screened which were positive for both ethanolic and aqueous extracts. This study suggests that possible mechanism of this activity may be due to free radical-scavenging and antioxidant activities which may be due to the presence of flavonoids in the extracts.
The contamination of surface environments with hydroxide rich wastes leads to the formation of high pH (>11.0) soil profiles. One such site is a legacy lime works at Harpur Hill, Derbyshire where ...soil profile indicated in-situ pH values up to pH 12. Soil and porewater profiles around the site indicated clear evidence of the presence of the α and β stereoisomers of isosaccharinic acid (ISA) resulting from the anoxic, alkaline degradation of cellulosic material. ISAs are of particular interest with regards to the disposal of cellulosic materials contained within the intermediate level waste (ILW) inventory of the United Kingdom, where they may influence radionuclide mobility via complexation events occurring within a geological disposal facility (GDF) concept. The mixing of uncontaminated soils with the alkaline leachate of the site resulted in ISA generation, where the rate of generation in-situ is likely to be dependent upon the prevailing temperature of the soil. Microbial consortia present in the uncontaminated soil were capable of surviving conditions imposed by the alkaline leachate and demonstrated the ability to utilise ISAs as a carbon source. Leachate-contaminated soil was sub-cultured in a cellulose degradation product driven microcosm operating at pH 11, the consortia present were capable of the degradation of ISAs and the generation of methane from the resultant H2/CO2 produced from fermentation processes. Following microbial community analysis, fermentation processes appear to be predominated by Clostridia from the genus Alkaliphilus sp, with methanogenesis being attributed to Methanobacterium and Methanomassiliicoccus sp. The study is the first to identify the generation of ISA within an anthropogenic environment and advocates the notion that microbial activity within an ILW-GDF is likely to influence the impact of ISAs upon radionuclide migration.
The energy-dependent cross section of the Be7(n,alpha)He4 reaction, of interest for the so-called cosmological lithium problem in big bang nucleosynthesis, has been measured for the first time from ...10 meV to 10 keV neutron energy. The challenges posed by the short half-life of Be7 and by the low reaction cross section have been overcome at n_TOF thanks to an unprecedented combination of the extremely high luminosity and good resolution of the neutron beam in the new experimental area (EAR2) of the n_TOF facility at CERN, the availability of a sufficient amount of chemically pure Be7, and a specifically designed experimental setup. Coincidences between the two alpha particles have been recorded in two Si-Be7-Si arrays placed directly in the neutron beam. The present results are consistent, at thermal neutron energy, with the only previous measurement performed in the 1960s at a nuclear reactor. The energy dependence reported here clearly indicates the inadequacy of the cross section estimates currently used in BBN calculations. Although new measurements at higher neutron energy may still be needed, the n_TOF results hint at a minor role of this reaction in BBN, leaving the long-standing cosmological lithium problem unsolved.
Solvent extraction of iron (III) from the HCl leach liquor of low grade iron ore tailings was studied with Aliquat 336, a quaternary amine in kerosene. p-Nonyl phenol was used as the third phase ...modifier. The effect of different parameters such as equilibration time, HCl concentration, H
+ concentration, Cl
− concentration and extractant concentration on extraction of iron was studied. The effect of different diluents such as xylene, benzene, toluene, diphenyl ether, diethyl ether, cyclohexane, hexanol, cyclohexanol and butanol on extraction of iron was investigated. The effect of various salts such as NaCl, NaNO
3, Na
2SO
4, NaOOCCH
3, and Na
3C
6H
5O
7·2H
2O in the feed solution within the concentrations of 0.5 to 2.5
M on extraction of iron was studied. It was observed that extraction of iron increased from 51.82 to 97.52% and from 5.81 to 97.19% with increase in HCl and extractant concentrations from 1.67 to 9.7
M and from 0.025 to 0.4
M, respectively. From the slope analysis study, the number of moles of H
+, Cl
− and Aliquat 336 associated with the extracted species was determined and the extracted species was found to be R
3NCH
3
·FeCl
4. The McCabe–Thiele plot for extraction of iron with 0.2
M Aliquat 336 illustrated 2-stages at 1:1 phase ratio and the loaded organic contained 0.338
M (18.8496
kg/m
3) iron indicating 98.57% extraction. The stripping of iron from the loaded organic carried out with distilled water showed quantitative stripping in 3-stages at O:A ratio of 2:1.
► Study on Fe extraction from low grade Fe ore tailing leach liquor with Aliquat 336. ► Extraction increased with increase of HCl and Aliquat 336 concentration. ► Diluent and salt effects are studied and thermodynamic data generated. ► Extraction of Fe in 2 stages at O:A
=
1:1, stripping of LO in 3 stages at O:A
=
2:1. ► Extracted species is R
3NCH
3·FeCl
4.
The anoxic, alkaline hydrolysis of cellulosic materials generates a range of cellulose degradation products (CDP) including α and β forms of isosaccharinic acid (ISA) and is expected to occur in ...radioactive waste disposal sites receiving intermediate level radioactive wastes. The generation of ISA's is of particular relevance to the disposal of these wastes since they are able to form complexes with radioelements such as Pu enhancing their migration. This study demonstrates that microbial communities present in near-surface anoxic sediments are able to degrade CDP including both forms of ISA via iron reduction, sulphate reduction and methanogenesis, without any prior exposure to these substrates. No significant difference (n = 6, p = 0.118) in α and β ISA degradation rates were seen under either iron reducing, sulphate reducing or methanogenic conditions, giving an overall mean degradation rate of 4.7 × 10(-2) hr(-1) (SE ± 2.9 × 10(-3)). These results suggest that a radioactive waste disposal site is likely to be colonised by organisms able to degrade CDP and associated ISA's during the construction and operational phase of the facility.
It remains particularly problematic to define the structures of native macromolecular assemblies, which are often of low abundance. Here we present a strategy for isolating complexes at endogenous ...levels from GFP-tagged transgenic cell lines. Using cross-linking mass spectrometry, we extracted distance restraints that allowed us to model the complexes' molecular architectures.
COVID-19, caused by the coronavirus SARS-CoV-2, represents a serious worldwide health issue, with continually emerging new variants challenging current therapeutics. One promising alternate ...therapeutic avenue is represented by nanobodies, small single-chain antibodies derived from camelids with numerous advantageous properties and the potential to neutralize the virus. For identification and characterization of a broad spectrum of anti–SARS-CoV-2 Spike nanobodies, we further optimized a yeast display method, leveraging a previously published mass spectrometry-based method, using B-cell complementary DNA from the same immunized animals as a source of VHH sequences. Yeast display captured many of the sequences identified by the previous approach, as well as many additional sequences that proved to encode a large new repertoire of nanobodies with high affinities and neutralization activities against different SARS-CoV-2 variants. We evaluated DNA shuffling applied to the three complementarity-determining regions of antiviral nanobodies. The results suggested a surprising degree of modularity to complementarity-determining region function. Importantly, the yeast display approach applied to nanobody libraries from immunized animals allows parallel interrogation of a vast number of nanobodies. For example, we employed a modified yeast display to carry out massively parallel epitope binning. The current yeast display approach proved comparable in efficiency and specificity to the mass spectrometry–based approach, while requiring none of the infrastructure and expertise required for that approach, making these highly complementary approaches that together appear to comprehensively explore the paratope space. The larger repertoires produced maximize the likelihood of discovering broadly specific reagents and those that powerfully synergize in mixtures.
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