Post-infectious bronchiolitis obliterans and subpleural cysts in a 30-month-old boy with down syndrome

Post-infectious bronchiolitis obliterans is a rare disease that may occur following a microbiological insult towards the lower respiratory tract causing a severe form of chronic obstructive airway disease. Subpleural lung cyst may occur in 20-36% of Down syndrome. We report a case of a 30-month-old Down syndrome child who had interesting radiological concurrent findings of bronchiolitis obliterans with subpleural cysts on High Resolution Computed Tomography (HRCT) thorax. This patient was born premature and had early onset pneumonia during the neonatal period. Subsequently, he had three episodes of pneumonias at 18, 19 and 26 months. He presented with recurrent symptoms of cough, wheeze, rapid breathing and had features of persistent airway obstruction characterized by chest hyperinflation, persistent tachypnoea with crepitations and rhonchi despite on regular bronchodilators. The only positive culture was Influenza B from his nasopharyneal aspirate culture. To our knowledge, this is the first reported case with both radiological entities in a child with Down syndrome

An Ideal of Retirement Villages Business Model in Malaysia: Analysis of case studies

There are three types of retirement villages development business models: the outright sale model, the lease for life model and the rental model. This paper aims to investigate the influence elements of chosen business models adopted in Malaysia's retirement village development. This study uses a qualitative research method through interviews with the selected developers as case studies. The prominent contemplation for developing retirement villages are sustainability, practicality, profitability and land availability. Local developers have been mindful and creative in implementing their retirement village business models

Microstructure Analysis of Aluminum Alloy and Copper Alloy Circular Shells After Multiaxial Plastic Buckling

Aluminum and copper cylindrical shells were plastically buckled under quasi-static and dynamic loading conditions with an Absorption Compression-Torsion Plasticity (ACTP: Patent No. WO 2005090822) combined mechanical testing device. Optical microscopy and transmission electron microscopy (TEM) analysis were used to study the microscopic evolutions in the mechanically buckled aluminum and copper alloy samples. Optical microscopy showed evidence of the presence of second-phase particles in both the aluminum and copper alloys samples. Under dynamic loading aluminum samples showed more energy absorption as compared to copper samples. Material flow lines were more pronounced in the copper samples when observed by optical microscopy. The evidence that supports the increased energy absorption in the aluminum cylindrical shells can be supported by the TEM analysis more than the optical microscopy analysis. The TEM results showed highly oriented textured morphology with the presence of few dislocation cells structures and sub-structures

Passively Q-Switched pulse erbium doped fiber laser using Antimony (III) Telluride (Sb2Te3) thin film as saturable absorber

This paper demonstrates on an antimony telluride (Sb2Te3) thin film sandwiched between two fiber ferrule as saturable absorber for Qswitched pulsed Erbium doped fiber (EDF) laser. The saturable absorber is fabricated by dissolving Antimony (III) Telluride powder into PVA solution and dry in the ambient temperature for 48 hours. Then, 1 mm2 x 1 mm2 Sb2Te3-PVA film based saturable absorber is sandwiched in between FC/PC ferrule for Q-switched laser generation. The modulation depth of the Sb2Te3 is measured as 28.01% with input intensity 0.02 MW/cm2 . The developed passive saturable absorber integrated in EDF laser in ring cavity and the characterised pulse is with repetition rates of 30.21 kHz, shortest pulse width of 3.26 µs and signal-noise-ratio (SNR) of 42 dB. The maximum output pulse energy is achieved at pump power 69.5 mW with 29.5 nJ and the output power 0.89 mW

Variety of Antibody Responses to BNT162b2 and BBIBP-CorV Vaccinations Against COVID-19 Infections in Baghdad and Fallujah, Iraq

The huge impact of COVID-19 worldwide led to the rapid development of vaccines with inadequate data about its longevity, effectivity, and safety. This study aims to evaluate the effectiveness and safety of COVID-19 vaccines available in Iraq and to measure longevity of created antibody response among different time points of both Pfizer-BioNTech and Sinopharm vaccines in Baghdad and Fallujah, Iraq. A two-axis method was used: the first was cross sectional study on the vaccination state for COVID-19 in Baghdad and Fallujah, using an online survey contained questions about city, vaccine type, side effect, pre and post infections, and chronic diseases. The second part involved a prospective observational study of the vaccine’s immunological effectiveness and stability in 60 serum samples from completely vaccinated individuals (second dose) of Pfizer or Sinopharm along different time points (1 - 6 months) by measuring the SARS-CoV-2 Anti-RBD-IgG concentration and evaluating its correlation with pre-infection with COVID-19. Among different types of vaccines available in Iraq, people in Baghdad and Fallujah preferred Pfizer vaccine over other available types, particularly those with chronic diseases. No statistically significant difference was noticed between IgG concentrations at different points of time, IgG concentrations in Pfizer vaccinated individuals were more elevated than Sinopharm, and all of Pfizer vaccinated people showed positive results. Our study established a synergistic impact between recent COVID-19 infection and vaccination, leading to increased levels of IgG antibodies, notably in individuals who received the Pfizer vaccine. Additionally, our findings demonstrate that IgG concentrations remained stable in vaccinated individuals even six months after completing the vaccination with second dose

Relative assessment of anti-quorum sensing in Piper betle leaves extract via pyoverdin assay

Anti-quorum sensing property has been a popular alternative approach over bactericidal/bacteriostatic property in combating bacterial infection while simultaneously tackling the dilemma of antibiotic resistance. We presented pyoverdin assay as an initial screening to qualitatively determine the anti-quorum sensing activity in Piper betle by measuring the loss of absorbance at wavelength 630 nm. Growth of Pseudomonas aeruginosa was proven to be unaffected by the presence of the P. betle leaves extract. The regression value (R2) of the quorum sensing (QS) activity in untreated supernatant of P. aeruginosa was 0.9636 and we presented the QS activity in fold-change, normalized to untreated sample for a fair comparison between batch of assays. We further assessed the QS activity in the extracts of P. betle leaves and found the QS activity of P. aeruginosa grown in the presence of ethyl acetate extract at 200 μg/ml was reduced to 0.6-fold. As the concentrations went lower, higher fold of QS activity was observed, suggesting that P. betle leaves extract is demonstrating anti-QS activity at a higher concentration. Further fractionate of ethyl acetate crude extracts resulted in three fractionates with high anti-QS activity with >50% reduction in QS activity and five fractionates with intermediate anti-QS activity. The use of pyoverdin assay to qualitatively portray the anti-QS activity could shorten the lengthiness of extracting and measuring the signaling molecule yet, produces reliable information to screen for anti-QS activity and guide for further fractionation and purification of bioactive compound

Effect of Aluminium Content on the Tensile Properties of Mg-Al-Zn Alloys

ABSTRAC

Abrasive wear failure analysis of tungsten carbide hard facing on carbon steel blade

This study investigate the abrasive wear failure of tungsten carbide hardfacing on continuous digester (CD) blade (carbon steel) in an environment of sulphuric acid and ilmenite ore mixture. Comparison being made on the hardness, thickness and microstructural of the hardfacing between unworn and 3 months old worn blade on few locations around the blade. The cross sections of the blade revealed non-uniform coverage of the hardfacing on the blade for both worn and unworn blade. The edge of the blade has the least amount of hardfacing thickness which with time acts as the point of failure during the wear process. The hardness obtained from both the unworn and worn samples are around 25% lower from the hardfacing electrode manufacturer’s hardness specification. Microstructural micrograph analysis of the hardfacing revealed non uniform size carbide with non-uniform distributed of carbide in the hardfacing layer

Bromocarbons in the tropical coastal and open ocean atmosphere during the 2009 Prime Expedition Scientific Cruise (PESC-09)

Abstract. Atmospheric concentrations of very short-lived species (VSLS) bromocarbons, including CHBr3, CH2Br2, CHCl2Br, CHClBr2, and CH2BrCl, were measured in the Strait of Malacca and the South China and Sulu–Sulawesi seas during a two-month research cruise in June–July 2009. The highest bromocarbon concentrations were found in the Strait of Malacca, with smaller enhancements in coastal regions of northern Borneo. CHBr3 was the most abundant bromocarbon, ranging from 5.2 pmol mol−1 in the Strait of Malacca to 0.94 pmol mol−1 over the open ocean. Other bromocarbons showed lower concentrations, in the range of 0.8–1.3 pmol mol−1 for CH2Br2, 0.1–0.5 pmol mol−1 for CHCl2Br, and 0.1–0.4 pmol mol−1 for CHClBr2. There was no significant correlation between bromocarbons and in situ chlorophyll a, but positive correlations with both MODIS and SeaWiFS satellite chlorophyll a. Together, the short-lived bromocarbons contribute an average of 8.9 pmol mol−1 (range 5.2–21.4 pmol mol−1) to tropospheric bromine loading, which is similar to that found in previous studies from global sampling networks (Montzka et al., 2011). Statistical tests showed strong Spearman correlations between brominated compounds, suggesting a common source. Log–log plots of CHBr3/CH2Br2 versus CHBr2Cl/CH2Br2 show that both chemical reactions and dilution into the background atmosphere contribute to the composition of these halocarbons at each sampling point. We have used the correlation to make a crude estimate of the regional emissions of CHBr3 and to derive a value of 32 Gg yr−1 for the Southeast (SE) Asian region (10° N–20° S, 90–150° E). Finally, we note that satellite-derived chlorophyll a (chl a) products do not always agree well with in situ measurements, particularly in coastal regions of high turbidity, meaning that satellite chl a may not always be a good proxy for marine productivity. We would like to thank MOSTI (Malaysian Ministry of Science, Technology and Innovation). for giving opportunities and financial support for the University of Malaya (UM) and Universiti Kebangsaan Malaysia to participate in this scientific cruise, and other Malaysian public universities and agencies who helped during sampling. The Malaysian Royal Navy is thanked for their help and assistance in all aspects of the cruise. We also thank the SHIVA European FP7 project (grant 226224), NERC, NERC-NCAS and the British Council, through a PMI2 grant, for their support. Neil Harris would like to thank NERC for his Research Fellowship; Emma Leedham and Matt Ashfold thank NERC for studentships, and Doreena Dominick, Lin Chin Yik, Fatimah Ahamad and Nur Ily Hamizah for their assistance and the Ministry of Higher Education Malaysia (KPT’s) ERGS grant ER025-2013A. Finally, we also would like to thank Universiti Kebangsaan Malaysia (UKM) for the ICONIC-2013-004 grant, MOSTI e-science grant 04-01-02-SF-0752 for Universiti Kebangsaan Malaysia (UKM), UKM GGPM-2013-080 and UKM DPP-2014-162 and GUP-2013-057 for financial support.This paper was originally published in Atmospheric Chemistry and Physics, 14, 8137-8148, doi:10.5194/acp-14-8137-2014, 201