Nickel Nanocatalyst Supported Single-Step Hydroconversion of Dicyclopentadiene (DCPD) into High Energy-Density Fuel, Exo-Tetrahydrodicyclopentadiene (Exo-THDCPD).

There are several chemical methods for the synthesis of high energy-density fuel, exotetrahydrodicyclopentadiene (exo-THDCPD), however, still there is a challenge to synthesize exo-THDCPD conveniently. In present work, the exo-THDCPD from dicyclopentadiene (DCPD) has successfully synthesized through simplest and greener single step hydroconversion reaction over mesoporous supported nickel nanocatalyst (Ni/MCM-41). The reaction performed in autoclave under a hydrogen pressure ranging from 300-400 (Psi), temperature range 130-150 °C and progress has been monitored by gas chromatography which reveals that the reaction mechanism goes through dissociation-recombination of DCPD. The major reaction parameters such as temperature, pressure and nanocatalyst have been experimentally examined for the yield (85%) of the product. The structural analysis of exo-THDCPD is carried out by 1H NMR and FTIR techniques and the physicochemical properties have also been evaluated. Good quality nanocatalyst Ni/MCM-41 has been synthesized by impregnation incipient wetness method and characterized by XRD, EDAX, TEM, and BET techniques. The nanocatalyst is highly reactive due to its mesoporous structure having appropriate size and shape which gives free diffusion of the molecules. Repeatability of the nanocatalyst shows good reactivity up to the four runs.

New insights towards strikingly improved room temperature ethanol sensing properties of p-type Ce-doped SnO2 sensors.

In this article, room temperature ethanol sensing behavior of p-type Ce doped SnO2 nanostructures are investigated successfully. Interestingly, it is examined that the abnormal n to p-type transition behavior is caused by Ce doping in SnO2 lattice. In p-type Ce doped SnO2, Ce ion substituting the Sn is in favor of generating excess holes as oxygen vacancies, which is associated with the improved sensing performance. Although, p-type SnO2 is one of the important materials for practical applications, it is less studied as compared to n-type SnO2. Pure and Ce doped SnO2 nanostructures were successfully synthesized by chemical co-precipitation method. The structure, surface morphology, unpaired electrons (such as free radicals), and chemical composition of obtained nanoparticles were studied by various kinds of characterization techniques. The 9% Ce doped SnO2 sensors exhibit maximum sensor response of ~382 for 400 ppm of ethanol exposure with fast response time of ~5 to 25 sec respectively. Moreover, it is quite interesting that such enhancement of ethanol sensing is unveiled at room temperature, which plays a key role in the quest for better ethanol sensors. These remarkably improved sensing results are attributed to uniformly distributed nanoparticles, lattice strain, complex defect chemistry and presence of large number of unpaired electrons on the surface.

Ferromagnetic resonance of NiCoFe2O4 nanoparticles and microwave absorption properties of flexible NiCoFe2O4-carbon black/poly(vinyl alcohol) composites.

The effect of cationic disorder and particle morphology on the ferromagnetic resonance (FMR) of NiCoFe2O4 nanoparticles (NPs) and the electromagnetic shielding effectiveness of flexible composites (wherein the nanoparticles are used as fillers) has been presented. Upon annealing at 1000 °C, spherical, ∼25 nm, single crystalline (as-prepared) NPs are transformed into octahedral, ∼200 nm, polycrystalline (annealed) NPs and change the cationic distribution significantly. The effect of shape, size and cationic distribution on the resonance properties has been discussed using the randomly-oriented anisotropic-axis model. The temperature dependent evolution of FMR spectra has been found to be consistent with a Bloch spin-relaxation model. Analysis of the FMR spectra reveals that NiCoFe2O4 nanoparticles have a large internal magnetic field along with broad FMR linewidths of ∼2-3 kOe, signifying high magnetic losses that are essential for the absorption of electromagnetic (EM) waves. Next, NiCoFe2O4-carbon black (NCF-CB) hybrids grafted in a PVA matrix, as flexible composite films with a thickness of ∼1.5 mm, are assessed for EM wave absorption properties in the range of 8-18 GHz. As compared to annealed-NCF-CB/PVA (21 dB, ∼99.5%), the as-prepared-NCF-CB/PVA composite film exhibits significantly large SE of 27 dB (∼99.9% attenuation of the EM wave), with a dominant contribution from absorption (SEA ∼ 21 dB). The electrical conductivity, the electric modulus, and Cole-Cole plots reveal that the dielectric losses in the as-prepared-NCF-CB/PVA have significant contributions from cationic disorder and particle size, as compared to the annealed-NCF-CB/PVA composites. Cationic disorder increases the d-d electron transition probability between adjacent ionic pairs such as Co2+/Fe3+ and a reduced particle size creates large interfacial polarization in the as-prepared NCF/CB hybrids. Considerably large values of the Landes g-factor, magnetic anisotropy and better impedance matching indicate a dominant magnetic loss contribution in ap-NCF (g = 4.5) as compared to an-NCF (g = 2.5) at 300 K.

Observation of magnetic anomalies in one-step solvothermally synthesized nickel-cobalt ferrite nanoparticles.

Magnetic anomalies corresponding to the Verwey transition and reorientation of anisotropic vacancies are observed at 151 K and 306 K, respectively, in NiCoFe2O4 nanoparticles (NPs) synthesized by a modified-solvothermal method followed by annealing. Cationic disorder and spherical shape induced non-stoichiometry suppress the Verwey transition in the as-synthesized NPs. On the other hand, reorientation of anisotropic vacancies is quite robust. XRD and electron microscopy investigations confirm a single phase spinel structure and the surface morphology of the as-synthesized NPs changes from spherical to octahedral upon annealing. Rietveld analysis reveals that the Ni(2+) ions migrate from tetrahedral (A) to octahedral (B) sites upon annealing. The Mössbauer results show canted spins in both the NPs and the strength of superexchange is stronger in Co-O-Fe than Ni-O-Fe. Magnetic force images show that the as-synthesised NPs are single-domain whereas the annealed NPs are multi-domain octahedral particles. The FMR study reveals that both the NPs have a broad FMR line-width; and resonance properties are consistent with the random anisotropy model. The broad inhomogeneous FMR line-width, observation of the Verwey transition, tuning of the magnetic domain structure as well as the magnetic properties suggest that the NiCoFe2O4 ferrite NPs may be promising for future generation spintronics, magneto-electronics, and ultra-high-density recording media as well as for radar absorbing applications.

Influence of texture coefficient on surface morphology and sensing properties of W-doped nanocrystalline tin oxide thin films.

For the first time, a new facile approach based on simple and inexpensive chemical spray pyrolysis (CSP) technique is used to deposit Tungsten (W) doped nanocrystalline SnO2 thin films. The textural, optical, structural and sensing properties are investigated by GAXRD, UV spectroscopy, FESEM, AFM, and home-built sensing setup. The gas sensing results indicate that, as compared to pure SnO2, 1 wt % W-doping improves sensitivity along with better response (<2 s) and recovery time (<25 s) toward NO2 gas at operating temperatures of ∼225 °C. The optimal composition of 1 wt % W-doped films exhibit lowest crystallite size of the order of ∼8-10 nm with reduced energy band gap and large roughness values of 3.82 eV and 3.01 nm, respectively. Reduction in texture coefficient along highly dense (110) planes with concomitant increase along loosely packed (200) planes is found to have prominent effect on gas sensing properties of W-doped films.

Meta-analysis: the impact of disease activity at conception on disease activity during pregnancy in patients with inflammatory bowel disease.

BACKGROUND: The rate of exacerbation of inflammatory bowel disease (IBD) during pregnancy varies in the published literature. AIM: We sought to perform a systematic review and meta-analysis of the effects of disease activity at conception on disease course during pregnancy in women with IBD. METHODS: Published studies and abstracts from standard sources were screened for appropriate studies. Data were pooled and analysed using funnel and forest plots. Quality assessment scores were given using GRADE criteria. RESULTS: Fourteen studies were eligible for inclusion; ten studies contained patients with UC (N = 1130), and six studies contained patients with CD (N = 590). In patients with UC there was a significantly higher risk ratio of active disease during pregnancy in patients who commenced pregnancy with active disease (55%), when compared with those in remission at conception (36%) (RR 2.0, 95% CI: 1.5-3, P < 0.001). This risk was also higher in patients with CD (RR 2.0, 95% CI: 1.2-3.4, P = 0.006). Thirteen of the studies rated 'low' in all domains of a quality assessment, and there was significant statistical heterogeneity. CONCLUSIONS: Patients with IBD who conceive when their disease is active are more likely to have active disease during pregnancy than those who conceive when in remission. All studies used in this analysis had a high risk of bias therefore further studies are required.

Early vascular healing with biodegradable polymer coated sirolimus-eluting coronary stent implantation: assessed by optical coherence tomography results at 4-month follow-up.

AIM: The aim of this study was to evaluate the strut apposition and neointimal coverage of Supralimus-Core stent struts at 4 months after implantation using optical coherence tomography (OCT). METHODS: The Supralimus-Core OCT study is a retrospective, single-center study evaluating strut apposition and neointimal coverage with OCT at 4 months after stent implantation. A total of 12 patients, who had 15 stents implanted were included in the study. The OCT was obtained using a C7-XR FD-OCT (frequency-domain OCT) intravascular imaging system. Strut apposition, neointimal hyperplasia (NIH) thickness and stent coverage on each stent strut were evaluated. RESULTS: A total of 2870 struts and 1950 frames were analyzed from 15 stents. Average stent length was 29.3 mm. Average reference vessel diameter was 2.64 mm. Among 12 patients, 3 (25.0%) patients were with diabetes, 4 (26.7%) type B2 and 10 (66.7%) type C lesions. The apposed and covered struts were 2787 (97.11%), whereas malapposed and covered struts were 3 (0.10%), apposed and uncovered 49 (1.71%) and malapposed and uncovered 31 (1.08%). Mean NIH thickness was 155.1±55.2 µm. CONCLUSION: The present study suggests that Supralimus-Core stent has a favorable vascular healing pattern at 4 months after stent implantation in terms of stent-strut coverage and strut apposition. This information indicates that the Supralimus-Core stent is a promising solution for decreasing late stent restenosis and preventing stent thrombosis.

Laparoscopy-assisted surgery for neonatal intestinal atresia: single-center experience(*).

INTRODUCTION: Neonatal intestinal atresia surgery requires careful assessment of bowel patency, resection of the affected bowel and a diligent anastomosis. Traditional anastomosis with sutures via a laparoscopic approach would lengthen the surgical time. Various minimally invasive techniques have been reported for neonatal surgery. Our technique offers improved benefits of laparoscopy while observing good principles of surgery. MATERIALS AND SURGICAL TECHNIQUE: Using a three-port approach to aid careful laparoscopic inspection of the bowel, we performed laparoscopy-assisted neonatal intestinal atresia repair in three term neonates with no cardiorespiratory compromise. Anastomosis was manually performed after exteriorzation of the bowel via the umbilical port site without any extension of the original port-site incision. There were no complications or conversions to open approach. DISCUSSION: Our technique is an improvement over previously reported limited/umbilical laparotomy approaches and blends the benefits of laparoscopy and open surgery most effectively. Careful bowel inspection and assessment of patency could be safely and systematically performed laparoscopically with limited exteriorization of the bowel for rapid hand-sewn anastomosis and without compromising bowel viability. A multicenter randomized trial will be useful to compare the open laparotomy approach with our technique.

Beta-catenin is involved in alterations in mitochondrial activity in non-transformed intestinal epithelial and colon cancer cells.

BACKGROUND: Alteration in respiratory activity and mitochondrial DNA (mtDNA) transcription seems to be an important feature of cancer cells. Leukotriene D(4) (LTD(4)) is a proinflammatory mediator implicated in the pathology of chronic inflammation and cancer. We have shown earlier that LTD(4) causes translocation of beta-catenin both to the mitochondria, in which it associates with the survival protein Bcl-2 identifying a novel role for beta-catenin in cell survival, and to the nucleus in which it activates the TCF/LEF transcription machinery. METHODS: Here we have used non-transformed intestinal epithelial Int 407 cells and Caco-2 colon cancer cells, transfected or not with wild type and mutated (S33Y) beta-catenin to analyse its effect on mitochondria activity. We have measured the ATP/ADP ratio, and transcription of the mtDNA genes ND2, ND6 and 16 s in these cells stimulated or not with LTD(4). RESULTS: We have shown for the first time that LTD(4) triggers a cellular increase in NADPH dehydrogenase activity and ATP/ADP ratio. In addition, LTD(4) significantly increased the transcription of mtDNA genes. Overexpression of wild-type beta-catenin or a constitutively active beta-catenin mutant mimicked the effect of LTD(4) on ATP/ADP ratio and mtDNA transcription. These elevations in mitochondrial activity resulted in increased reactive oxygen species levels and subsequent activations of the p65 subunit of NF-kappaB. CONCLUSIONS: The present novel data show that LTD(4), presumably through beta-catenin accumulation in the mitochondria, affects mitochondrial activity, lending further credence to the idea that inflammatory signalling pathways are intrinsically linked with potential oncogenic signals.

Is there a positive effect of participation on a clinical trial for patients with advanced non-small cell lung cancer?

BACKGROUND: There is general belief that patients who enrolled on a clinical trial have better outcomes compared to those who are treated outside of a trial. We analyzed if there was a 'trial effect' for patients with advanced non-small cell lung cancer (NSCLC) treated with chemotherapy. MATERIALS AND METHODS: A retrospective analysis of cohorts of patients with advanced NSCLC who received chemotherapy inside and outside of a clinical trial were analyzed for response rates (RR), progression free survival (PFS), overall survival (OS), 1 and 2 year survival. RESULTS: There were 194 patients who received chemotherapy of which, 54 were on a clinical trial and 140 outside of it. For the whole group, the RR, median PFS, OS, one and two-year survivals were 35.4%, six months (range, 2-70), seven months (range, 2-72), 29.8% and 9.7% respectively. The differences in RR and PFS of patients who were treated inside and outside of a clinical trial were not significant (P=0.6164, 0.0881). The differences in median OS and one-year survivals between the groups were significant (P=0.0052, 0.022). For the whole group, patients who received II line chemotherapy had better OS (P< or = 0.0001). More patients in the trial group received II line chemotherapy (P=0.0004).The difference in the median OS between the groups continued to be significant even after patients who received II line chemotherapy were censored (P=0.0437). CONCLUSION: Patients with advanced NSCLC who were treated inside of a clinical trial had better OS compared to those who were treated outside of it.

Fusogenic peptide as diagnostic marker for detection of flaviviruses.

BACKGROUND: Dengue, Japanese encephalitis, West Nile encephalitis, yellow fever are the common flaviviral diseases associated with high morbidity and mortality. The initial symptoms of most of the flaviviral infections are similar to each other as well as to some other viral diseases. Making clinical diagnosis, therefore, becomes a challenging task for the clinician. Several studies have been reported on using detection of serum antibodies against flavivirus for the diagnosis of specific flaviviral disease; no field-based pan-flavi virus detection system is available, which can be used in low-endemicity areas for differentiation of flaviviral disease from other viral diseases. AIM: To identify a conserved amino acid sequence among all flaviviruses and evaluate the antibody formed against the conserved peptide to develop pan-flavivirus detection system. MATERIALS AND METHODS: In the present study we have compared amino acid sequences of several flaviviruses and identified a conserved amino acid sequence lying in domain II of envelope protein. RESULTS: A peptide having the conserved amino acid sequence was used to generate polyclonal antibodies and these antibodies were used to detect several flaviviruses. Anti-peptide polyclonal antibodies selectively recognized flaviviruses and did not detect non-flaviviruses. Anti-peptide antibodies detected presence of virus in serum spiked with pure virus preparations. CONCLUSION: The study offers a rationale for development of pan-flavivirus capture assay suitable for low endemic areas.

Simvastatin maintains steady patterns of GFR and improves AER and expression of slit diaphragm proteins in type II diabetes.

The factors determining the course of glomerular filtration rate (GFR) and albumin excretion rate (AER) and the expression of mRNA of slit diaphragm (SD) and podocyte proteins in microalbuminuric, hypertensive type II diabetic patients are not fully understood. GFR, AER, and SD protein mRNA were studied in 86 microalbuminuric, hypertensive, type II diabetics at baseline and after 4-year random double-blind treatment either with 40 mg simvastatin (Group 1) or with 30 g cholestyramine (Group 2) per day. Both groups had at baseline a GFR decay per year in the previous 2-4 years of 3 ml/min/1.73 m(2). Both Groups 1 and 2 showed a significant decrease of low-density lipoprotein cholesterol levels after simvastatin and cholestyramine treatment (P<0.01). No change from base line values was observed as for hs-C-reactive protein and interleukin-6. A significant decrease of 8-hydroxydeoxyguanosine urinary excretion was observed after simvastatin treatment. GFR did not change from baseline with simvstatin, whereas a decrease was observed with cholestyramine treatment (simvastatin vs cholestyramine: -0.21 vs -2.75 ml/min/1.73 m(2), P<0.01). AER decreased in Group 1 (P<0.01), but not in Group 2 patients. Real-time polymerase chain reaction measurement of mRNA SD proteins (CD2AP, FAT, Actn 4, NPHS1, and NPHS2) significantly increased in kidney biopsy specimens after simvastatin, but not cholestyramine treatment. Simvastatin, but not cholestyramine, 4-year treatment maintains steady patterns of GFR, and improves AER and expression of SD proteins in type II diabetes, despite similar hypocholesterolemic effects in circulation.

Comparison of a dipstick dot-ELISA with commercial assays for anti-dengue virus IgM antibodies.

Dengue virus infections have undergone dramatic expansion in range, affecting several tropical and subtropical regions of the world. Dengue virus causes life-threatening complications characterized by dengue hemorrhagic fever and dengue shock syndrome. No standard validated test systems are available for serological diagnosis of dengue virus infection. This creates problems in the diagnosis and proper management of patients. Evaluation of a Defense Research and Development Establishment (DRDE) dengue virus dipstick dot-ELISA test, developed in house, vis-à-vis commercially available immunodiagnostic kits was carried out for detection of IgM antibodies. The DRDE dengue dipstick dot-ELISA was performed on the basis of the dot-ELISA principle. Commercial tests, namely, the Panbio Dengue IgM Capture ELISA system (Panbio, Sinnamon Park, Australia) and Pathozyme Dengue M (Omega Diagnostics, Alva, UK), were performed according to the manufacturers' protocols. Ninety-one serum samples collected from the states of Kerala and Delhi, India during August and November of 2004 were used in the present study. The overall agreement among all three tests was found to be only 72.16% for IgM antibodies. Correlations between the DRDE dipstick dot-ELISA and the Panbio kit, between the DRDE dipstick dot-ELISA and the Pathozyme Dengue M kit, and between the Panbio kit and the Pathozyme Dengue M kit were found to be 96, 93, and 94%, respectively. Although the Panbio kit is widely used in various laboratories in India, the DRDE dipstick dot-ELISA promises to be a useful kit because of its field applicability and comparable sensitivity.

Use of a tissue expander and a polyglactic acid (Vicryl) mesh to reduce radiation enteritis: case report and literature review.

Management of stage IV rhabdomyosarcoma comprises systemic chemotherapy with local control by conservative surgery and radiotherapy. Abdominal radiotherapy may lead to radiation enteritis causing such serious morbidity as malabsorption, fistulae or stricture formation. The risk increases with the dose of radiation and length of bowel involved. Various methods have been utilised to displace the bowel from the radiation field. Usually these are applied in patients requiring pelvic irradiation. We report a case of metastatic alveolar rhabdomyosarcoma requiring radiotherapy to the right renal bed. Effective displacement of small bowel from the tumour site was achieved by a combined use of a tissue expander and Vicryl mesh. There were no complications from the surgery. This is the first report discussing combined use of a tissue expander and Vicryl mesh to aid radiotherapy to the renal fossa in a paediatric patient.

Congenital malformations of the diaphragm: findings of the West Midlands Congenital Anomaly Register 1995 to 2000.

OBJECTIVES: To describe trends in incidence, associated anomalies, clinical outcomes and sensitivity of prenatal diagnosis for congenital malformations of the diaphragm in the West Midlands Region between 1995 and 2000. METHODS: Information was retrieved from a population-based register of major congenital malformations in a health region of England, the West Midlands Congenital Anomaly Register (WMCAR), between 1995 and 2000. RESULTS: One hundred and sixty-one confirmed cases of congenital malformations of the diaphragm were notified from 396 577 births. This gives an incidence of 4.1 per 10,000 births. After natural losses and terminations, the incidence at birth was 2.9 per 10,000 registered births. For live-born cases, the infant mortality rate was 317 per 1000 births. 47% of the cases had additional structural or chromosomal anomalies; the infant mortality rate for these complex cases was 533 per 1000, an increased relative risk of 2.37 compared with isolated lesions. 66% of the cases were diagnosed prenatally, 51% of isolated lesions and 84% of complex cases. Fourteen prenatally diagnosed cases (12%) were false-positives; however, 11 of these cases had other significant pathology. These 14 cases were not included in the 161 confirmed cases. CONCLUSION: Congenital malformations of the diaphragm remain associated with considerable infant mortality. Most cases are now diagnosed before birth and the prognosis is adversely affected by the presence of other structural or chromosomal anomalies. This presents significant challenges for those involved in counselling the parents of affected fetuses.

Postoperative pneumatosis intestinalis in infants does not automatically preclude enteral feeding.

BACKGROUND: A degree of feed intolerance after neonatal abdominal surgery is common but in an otherwise well baby enteral feeding usually is continued at the highest tolerated level. However, the presence of rectal bleeding, pneumatosis intestinalis, or portal vein gas seen on plain abdominal x-rays suggest the possibility of postoperative necrotising enterocolitis. When this happens feedings usually are stopped for 7 to 10 days, and intravenous antibiotics and total parental nutrition are commenced. METHODS: The authors report 12 episodes of rectal bleeding and 11 episodes of pneumatosis intestinalis in 3 infants who previously had undergone neonatal abdominal surgery for intestinal malformations. In 7 of these episodes, feedings were neither stopped nor were antibiotics given. At the time of these 7 episodes, the infants were more than 3 kg in weight, had no significant cardiac or respiratory pathology, were all clinically stable, had no evidence of peritonitis, had no thrombocytopenia, and were greater than 37 weeks postconception. RESULTS: The 3 infants were monitored closely. There were no early or late problems observed attributable to this management. CONCLUSION: Carefully selected clinically stable patients that have postoperative pneumatosis intestinalis or exhibit rectal bleeding may be successfully managed by reduced enteral feedings with no antibiotics. J Pediatr Surg 36:1820-1823.