Detailed Inspection of γ-ray,Fast and Thermal Neutrons Shielding Competence of Calcium Oxide or Strontium Oxide Comprising Bismuth Borate Glasses

For both the B₂O₃-Bi₂O₃-CaO and B₂O₃-Bi₂O₃-SrO glass systems, γ-ray and neutron attenuation qualities were evaluated. Utilizing the Phy-X/PSD program, within the 0.015–15 MeV energy range, linear attenuation coefficients (µ) and mass attenuation coefficients (μ/ρ) were calculated, and the attained μ/ρ quantities match well with respective simulation results computed by MCNPX, Geant4, and Penelope codes. Instead of B₂O₃/CaO or B₂O₃/SrO, the Bi₂O₃ addition causes improved γ-ray shielding competence, i.e., rise in effective atomic number (Z_eff) and a fall in half-value layer (HVL), tenth-value layer (TVL), and mean free path (MFP). Exposure buildup factors (EBFs) and energy absorption buildup factors (EABFs) were derived using a geometric progression (G–P) fitting approach at 1–40 mfp penetration depths (PDs), within the 0.015–15 MeV range. Computed radiation protection efficiency (RPE) values confirm their excellent capacity for lower energy photons shielding. Comparably greater density (7.59 g/cm³), larger μ, μ/ρ, Z_eff, equivalent atomic number (Z_eq), and RPE, with the lowest HVL, TVL, MFP, EBFs, and EABFs derived for 30B₂O₃-60Bi₂O₃-10SrO (mol%) glass suggest it as an excellent γ-ray attenuator. Additionally, 30B₂O₃-60Bi₂O₃-10SrO (mol%) glass holds a commensurably bigger macroscopic removal cross-section for fast neutrons (Σ_R) (=0.1199 cm⁻¹), obtained by applying Phy-X/PSD for fast neutrons shielding, owing to the presence of larger wt% of ‘Bi’ (80.6813 wt%) and moderate ‘B’ (2.0869 wt%) elements in it. 70B₂O₃-5Bi₂O₃-25CaO (mol%) sample (B: 17.5887 wt%, Bi: 24.2855 wt%, Ca: 11.6436 wt%, and O: 46.4821 wt%) shows high potentiality for thermal or slow neutrons and intermediate energy neutrons capture or absorption due to comprised high wt% of ‘B’ element in it.     

Mesoporous superacid catalysts for valorisation of refinery naphtha stream

In the current petroleum refining scenario, many refineries end up with surplus naphtha which is either absorbed into the gasoline pool or exported at unattractive prices. Therefore, several options for naphtha valorisation are currently being explored. The usage of Liquified Petroleum Gas (LPG) as a fuel in heating appliances, cooking equipment and automobiles is rapidly increasing. The high specific calorific value, high octane number, clean and efficient combustion of LPG distinguish it as an extremely promising fuel of the future. In the current work, tungstophosphoric acid (TPA) supported on four different mesoporous silica supports were investigated as mesoporous superacids for hydroconversion of refinery naphtha using n-heptane as a model feedstock. The varied levels of interactions of prepared mesoporous silica with tungstophosphoric acid catalysts were observed to have a prominent effect on the strength of the acid sites generated on silica surfaces and as a result affected heptane hydroconversion activity and selectivity of isomerized and cracked products. Interestingly, activity could be tuned towards selective cracking or isomerization-cracking by selection of a suitable topology of mesoporous silica. Hexagonal Mesoporous Silica (HMS) and plugged SBA-15 supported TPA catalysts demonstrated high n-heptane conversion activity and isomerization selectivity whereas KIT-6 and SBA-15 supported TPA catalysts demonstrated high cracking selectivity to LPG.

TPA silanol interactions in mesoporous TPA silica composites govern the strength of acid sites, activity and selectivity.     

Pars plana modified Baerveldt implant versus neodymium:YAG cyclophotocoagulation in the management of neovascular glaucoma

OBJECTIVE: To determine the relative effectiveness of neodymium:YAG cyclophotocoagulation (NCYC) and pars plana modified Baerveldt implant (PPBI) surgery on intraocular pressure (IOP) control in eyes with neovascular glaucoma (NVG). PARTICIPANTS: In this retrospective comparative group study, 30 patients with NVG treated with contact NCYC were compared with 18 patients who underwent PPBI. Patients groups were not statistically dissimilar with respect to the underlying disorder-causing angle and iris neovascularization, intraocular pressure, and patient's age. RESULTS: During a follow up of 6 months, an IOP control of > or = 6 and < or = 21 mm Hg was achieved in 23 eyes (76.6%) treated with NCYC compared with 17 eyes (94.4%) receiving PPBI (P = 0.13). Among eyes that had unsuccessful outcome in both groups, the proportions with persistently high IOP or hypotony were greater in the NCYC group than in the PPBI group. Based on our criteria, the cumulative proportion of failure in the NCYC group was 23.3% at 6 months as compared to 5.6% in the PPBI group. Seven eyes (23.3%) in the NCYC group lost light perception versus 1 eye (5.6%) in the PPBI group. The incidence of postoperative choroidal effusion (36%) was higher in the PPBI group. CONCLUSIONS: This study suggests that in the management of NVG, PPBI surgery more frequently controls IOP in a medically acceptable range with less hypotony and greater preservation of visual acuity than NCYC.     

Adeno-associated virus 2-mediated antiangiogenic cancer gene therapy: long-term efficacy of a vector encoding angiostatin and endostatin over vectors encoding a single factor

Angiogenesis is characteristic of solid tumor growth and a surrogate marker for metastasis in many human cancers. Inhibition of tumor angiogenesis using antiangiogenic drugs and gene transfer approaches has suggested the potential of this form of therapy in controlling tumor growth. However, for long-term tumor-free survival by antiangiogenic therapy, the factors controlling tumor neovasculature need to be systemically maintained at stable therapeutic levels. Here we show sustained expression of the antiangiogenic factors angiostatin and endostatin as secretory proteins by recombinant adeno-associated virus 2 (rAAV)-mediated gene transfer. Both vectors provided significant protective efficacy in a mouse tumor xenograft model. Stable transgene persistence and systemic levels of both angiostatin and endostatin were confirmed by in situ hybridization of the vector-injected tissues and by serum ELISA measurements, respectively. Whereas treatment with rAAV containing either endostatin or angiostatin alone resulted in moderate to significant protection, the combination of endostatin and angiostatin gene transfer from a single vector resulted in a complete protection. These data suggest that AAV-mediated long-term expression of both endostatin and angiostatin may have clinical utility against recurrence of cancers after primary therapies and may represent rational adjuvant therapies in combination with radiation or chemotherapy.     

Does applying the Canadian Cervical Spine rule reduce cervical spine radiography rates in alert patients with blunt trauma to the neck? A retrospective analysis

Background  

A cautious outlook towards neck injuries has been the norm to avoid missing cervical spine injuries. Consequently there has been an increased use of cervical spine radiography. The Canadian Cervical Spine rule was proposed to reduce unnecessary use of cervical spine radiography in alert and stable patients. Our aim was to see whether applying the Canadian Cervical Spine rule reduced the need for cervical spine radiography without missing significant cervical spine injuries.     

Evidence for multiple signaling pathways in single squid olfactory receptor neurons

At least two different G-protein-mediated transduction cascades, the adenylate cyclase and phospholipase C (PLC) pathway, process chemosensory stimuli for various species. In squid olfactory receptor neurons (ORNs), physiological studies indicate that both pathways may be present; however, confirmation of the transduction molecules at the protein level is absent. Here we provide evidence that the G-proteins involved in both adenylate cyclase and PLC pathways are present in squid ORNs (Lolliguncula brevis). We used immunoblotting to show that Galpha(olf), Galpha(q), and a downstream effector, enzyme PLC140, are present in the squid olfactory epithelium (OE). To localize these proteins to one or more of the five morphological cell types described for squid OE, paraformaldehyde-fixed olfactory organs were cryosectioned (10 microm), double-labeled for Galpha(olf), Galpha(q), or PLC140, and imaged. Analysis of serial sections from entire olfactory organs for epithelial area and patterns of immunofluorescence revealed a region of highest immunoreactivity at the anterior half of the organ. At the cellular level, type 1 cells could not be distinguished morphologically and were not included in the analysis. The three labeling patterns observed in type 2 cells were Galpha(q) alone, PLC140 alone, and colocalization of Galpha(q) and PLC140. Subsets of cell types 3, 4, and 5 showed colocalization of Galpha(olf) with Galpha(q) but not with PLC140. These data suggest that the PLC pathway predominates in type 2 cells; however, coexpression of Galpha(olf) with Galpha(q) in cell types 3, 4, and 5 suggests that both pathways may participate in olfactory transduction in non-type 2 squid ORNs.     

The efficacy of a network intervention to reduce HIV risk behaviors among drug users and risk partners in Chiang Mai,Thailand and Philadelphia,USA

This HIV Prevention Trials Network study assessed the efficacy of a network-oriented peer education intervention promoting HIV risk reduction among injection drug users and their drug and sexual network members in Chiang Mai, Thailand and Philadelphia, USA. The study was designed to test impact on HIV infection, but the infection rate was low and the study was terminated early. This paper reports efficacy on outcomes of self-reported HIV risk behaviors. We enrolled 414 networks with 1123 participants. The experimental intervention consisted of six small group peer educator training sessions and two booster sessions delivered to the network index only. All participants in both arms received individual HIV counseling and testing. Follow-up visits occurred every six months for up to 30 months. There were 10 HIV seroconversions, 5 in each arm. The number of participants reporting injection risk behaviors dropped dramatically between baseline and follow-up in both arms at both sites. Index members in the intervention arm engaged in more conversations about HIV risk following the intervention compared to control indexes. There was no evidence of change in sexual risk as a result of the intervention. Reductions in injection risk behaviors were observed: 37%, 20%, and 26% reduction in odds of sharing cottons, rinse water and cookers, respectively, and 24% reduction in using a syringe after someone else. Analysis of the individual sites suggested a pattern of reductions in injection risk behaviors in the Philadelphia site. In both sites, the intervention resulted in index injection drug users engaging in the community role of discussing reduction in HIV injection risk behaviors. The intervention did not result in overall reductions in self-reported sexual risk behaviors, and although reductions in injection risk behaviors were observed, the overall efficacy in reducing risk was not established.