The impact of celestial pole offset modelling on VLBI UT1 Intensive results

Very Long Baseline Interferometry (VLBI) Intensive sessions are scheduled to provide operational Universal Time (UT1) determinations with low latency. UT1 estimates obtained from these observations heavily depend on the model of the celestial pole motion used during data processing. However, even the most accurate precession-nutation model, IAU 2000/2006, is not accurate enough to realize the full potential of VLBI observations. To achieve the highest possible accuracy in UT1 estimates, a celestial pole offset (CPO), which is the difference between the actual and modelled precession-nutation angles, should be applied. Three CPO models are currently available for users. In this paper, these models have been tested and the differences between UT1 estimates obtained with those models are investigated. It has been shown that neglecting CPO modelling during VLBI UT1 Intensive processing causes systematic errors in UT1 series of up to 20 microarcseconds. It has been also found that using different CPO models causes the differences in UT1 estimates reaching 10 microarcseconds. Obtained results are applicable to the satellite data processing as well.Comment: 8 pp., accepted for publication in Journal of Geodes

Effect of different concentrations of red palm olein on antioxidant enzymes activity of rat liver

The objective of this study was to evaluate the effect of different concentrations of red palm olein (RPO) on antioxidant enzymes activity of rat liver. Seventy eight (78) rats were randomly divided into thirteen (13) groups of 6 rats per group and treated with different concentrations of RPO (5, 10 and 15%) for 2, 4 and 8 weeks. Rats in the control group were given normal rat pellet only, while those in treated groups, 5, 10 and 15% of additional RPO were given. After 2, 4 and 8 weeks of treatment, the catalase (CAT) activity results showed that there was no significant difference (P>0.05) between the control group and the treated groups. The mean value of the catalase activity after 2 weeks in control group for 5, 10, and 15% were 1328, 1612, 1298 and 1270 U/mg, respectively. For superoxide dismutase (SOD), there was no significant difference (P>0.05) between the control group and treated groups after 2 and 8 weeks of treatment but there was significant difference (P<0.05) in the 15% RPO group after 4 weeks.Keywords: Red palm olein, catalase, superoxide dismutase, vitamin E

Interaction and Cooperative Nucleation of InAsSbP Quantum Dots and Pits on InAs(100) Substrate

An example of InAsSbP quaternary quantum dots (QDs), pits and dots–pits cooperative structures’ growth on InAs(100) substrates by liquid phase epitaxy (LPE) is reported. The interaction and surface morphology of the dots–pits combinations are investigated by the high-resolution scanning electron microscope. Bimodal growth mechanism for the both QDs and pits nucleation is observed. Cooperative structures consist of the QDs banded by pits, as well as the “large” pits banded by the quantum wires are detected. The composition of the islands and the pits edges is found to be quaternary, enriched by antimony and phosphorus, respectively. This repartition is caused by dissociation of the wetting layer, followed by migration (surface diffusion) of the Sb and P atoms in opposite directions. The “small” QDs average density ranges from 0.8 to 2 × 109 cm−2, with heights and widths dimensions from 2 to 20 nm and 5 to 45 nm, respectively. The average density of the “small” pits is equal to (6–10) × 109 cm−2 with dimensions of 5–40 nm in width and depth. Lifshits–Slezov-like distribution for the amount and surface density of both “small” QDs and pits versus their average diameter is experimentally detected. A displacement of the absorption edge toward the long wavelength region and enlargement toward the short wavelength region is detected by the Fourier transform infrared spectrometry

Invariant, super and quasi-martingale functions of a Markov process

We identify the linear space spanned by the real-valued excessive functions of a Markov process with the set of those functions which are quasimartingales when we compose them with the process. Applications to semi-Dirichlet forms are given. We provide a unifying result which clarifies the relations between harmonic, co-harmonic, invariant, co-invariant, martingale and co-martingale functions, showing that in the conservative case they are all the same. Finally, using the co-excessive functions, we present a two-step approach to the existence of invariant probability measures

Enhancement of In Vitro Skin Transport and In Vivo Hypoglycemic Efficacy of Glimepiride Transdermal Patches

Purpose: To utilize hydroxybutyl-β-cyclodextrin (HB-β-CD) and polyvinyl pyrrolidone (PVP) for the enhancement of the transdermal delivery of glimepiride (GMD).Methods: Matrix-type transdermal patches containing GMD, drug  coprecipitate or its inclusion complex were prepared using different gelling agents, viz, hydroxypropyl methylcellulose (HPMC), hydroxypropyl cellulose (HPC), carbopol and chitosan. In vitro skin permeation evaluation of the formulations was conducted using automated diffusion system. Selected patch formulations were assessed for hypoglycemic activity as well as for GMD plasma concentration in rats.Results: GMD- hydroxybutyl-β-cyclodextrin (HB-β-CD) binary systems (1:2 molar ratio) enhanced GMD aqueous solubility by > 10-fold. Diffusion test showed improved release of GMD-HB-β-CD inclusion complex compared with GMD alone. Maximum cumulative amounts of GMD- HB-β-CD that permeated through rat skin was 26.97 and 14.28 µg/cm2 for patches prepared with fchitosan and HPMC, respectively. Thus, GMD-chitosan  patches showed significantly higher (p < 0.05) drug permeation than GMD-HPMC after 6 h. Both chitosan and HPMC patches of GMD-HB-β-CD demonstrated substantial reduction (p < 0.05) in blood glucose level (192.67 ± 21.18 and 201 ± 15.11 mg/ dl, respectively), compared with the baseline value of 240 mg/ dl.Conclusion: Application of chitosan and HPMC transdermal patches of GMD-HB-β-CD can serve as a potential alternative to peroral GMD with improved bioavailability and patient compliance.Keywords: Glimepiride, Transdermal patch, Coprecipitate, Inclusion complex, Hydroxypropyl methylcellulose, Polyvinyl pyrrolidone, Chitosan, Skin permeatio

Bright betatron x-ray radiation from a laser-driven-clustering gas target

Hard X-ray sources from femtosecond (fs) laser-produced plasmas, including the betatron X-rays from laser wakefield-accelerated electrons, have compact sizes, fs pulse duration and fs pump-probe capability, making it promising for wide use in material and biological sciences. Currently the main problem with such betatron X-ray sources is the limited average flux even with ultra-intense laser pulses. Here, we report ultra-bright betatron X-rays can be generated using a clustering gas jet target irradiated with a small size laser, where a ten-fold enhancement of the X-ray yield is achieved compared to the results obtained using a gas target. We suggest the increased X-ray photon is due to the existence of clusters in the gas, which results in increased total electron charge trapped for acceleration and larger wiggling amplitudes during the acceleration. This observation opens a route to produce high betatron average flux using small but high repetition rate laser facilities for applications

Genome Sequence of Erythromelalgia-Related Poxvirus Identifies it as an Ectromelia Virus Strain

Erythromelagia is a condition characterized by attacks of burning pain and inflammation in the extremeties. An epidemic form of this syndrome occurs in secondary students in rural China and a virus referred to as erythromelalgia-associated poxvirus (ERPV) was reported to have been recovered from throat swabs in 1987. Studies performed at the time suggested that ERPV belongs to the orthopoxvirus genus and has similarities with ectromelia virus, the causative agent of mousepox. We have determined the complete genome sequence of ERPV and demonstrated that it has 99.8% identity to the Naval strain of ectromelia virus and a slighly lower identity to the Moscow strain. Small DNA deletions in the Naval genome that are absent from ERPV may suggest that the sequenced strain of Naval was not the immediate progenitor of ERPV