Method for retrieving range-resolved aerosol microphysical properties from polarization lidar measurements.

Aerosol microphysical properties, such as volume concentration (VC) and effective radius (ER), are of great importance to evaluate their radiative forcing and impacts on climate change. However, range-resolved aerosol VC and ER still cannot be obtained by remote sensing currently except for the column-integrated one from sun-photometer observation. In this study, a retrieval method of range-resolved aerosol VC and ER is firstly proposed based on the partial least squares regression (PLSR) and deep neural networks (DNN), combining polarization lidar and collocated AERONET (AErosol RObotic NETwork) sun-photometer observations. The results show that the measurement of widely-used polarization lidar can be reasonably used to derive the aerosol VC and ER, with the determination coefficient (R2) of 0.89 (0.77) for VC (ER) by use of the DNN method. Moreover, it is proven that the lidar-based height-resolved VC and ER at near-surface are well consistent with independent observations of collocated Aerodynamic Particle Sizer (APS). Additionally, we found that there are significant diurnal and seasonal variations of aerosol VC and ER in the atmosphere at Semi-Arid Climate and Environment Observatory of Lanzhou University (SACOL). Compared with columnar ones from the sun-photometer observation, this study provides a reliable and practical way to obtain full-day range-resolved aerosol VC and ER from widely-used polarization lidar observation, even under cloud conditions. Moreover, this study also can be applied to long-term observations by current ground-based lidar networks and spaceborne CALIPSO lidar, aiming to further evaluate aerosol climatic effects more accurately.

Gender Discrepancies in Middle Author Publications in US Academic General Surgery.

INTRODUCTION: To explore gender discrepancies in publications at general surgery departments, we performed a cross-sectional comparing the number of women and men at each academic rank and their number of first author (FA), middle author (MA), last author (LA), and total publications. METHODS: Thirty academic general surgery departments were randomly selected. For each faculty, we tabulated: first, middle, last names, gender, academic rank, educational leadership, year of medical school graduation, and additional graduate degrees. Bibliography, H-index, and citations were downloaded from the Scopus database. RESULTS: One thousand three hundred twenty-six faculty sampled, 881 (66.4%) men and 445 (33.5%) women. Men outnumbered women at all ranks, with increasing disparity at higher ranks. Men outnumbered women in all subspecialties-largest difference in transplant surgery (84.4% versus 15.6%, P < 0.001). Men at all ranks had more MA publications: assistant professor (rate ratio 1.20; 95% confidence interval, 1.01-1.43, P = 0.024), associate professor (1.65; 1.31-2.06, P < 0.001), and professor (1.50; 1.20-1.91, P = 0.008). Men associate professors had more LA publications (1.74; 1.34-2.37, P < 0.001). No differences found in FA publications at any rank, nor LA publications at assistant professor and professor ranks. At subspecialty level, men in surgical oncology (1.95; 1.55-2.45, P < 0.001) and transplant surgery (1.70; 1.09-2.66, P = 0.02) had more MA publications. CONCLUSIONS: While FA and LA publications did not differ significantly across genders, the largest difference lies in MA publications, beginning at junior ranks and persisting with seniority. Discrepancies in MA publications may reflect gender discrepancies in collaborative opportunities, hence total publications should be used cautiously when determining academic productivity.

Pharmacological Activities of Rhododendron afghanicum; an Endemic Species of Khyber Pakhtunkhwa, Pakistan.

Majority of different kinds of metabolites having therapeutic characteristics are thought to be stored in medicinal plants. So, the present study was aimed to explore the crude extract of leaves and stem of R. afghanicum for phytochemical screening and various pharmacological activities. Toxicological studies at 100 mg/kg showed 60 % mortality where its safe dose level was 90 mg/kg. Phytochemical screening revealed the presence of alkaloids, glycosides, flavonoids and tannins in both extracts. Bacterial strains were susceptible to (RLEt) and (RLM) crude extracts except Staphylococcus aureus. RSM showed maximum anti-inflammatory activity (20.16 %) followed by RSEt (20.14 %) where lowest activity was displayed by RLEt (18.46 %). Phytotoxic activity showed a substantial dose-dependent phyto-inhibition of Lemna minor. An outstanding cytotoxic potential was displayed with LD50 values of 9.46 and 13.03 µg/ml in both stem extracts. RLEt demonstrated a dose-dependent pain relief at 30, 60 and 90 mg/kg which was 31 %, 40 % and 52 % respectively. A considerable spasmolytic action was observed by the shrinkage of jejunum muscle in albino mice. RLEt at 1000 ppm showed (17 mm) and RLM at 1000 ppm showed (16 mm) zone of inhibition against Aspergillus niger. These findings support and corroborate the traditional applications of R. afghanicum for treating digestive, analgesic and inflammatory ailments.

Appraising the characteristics of particulate matter from leather tanning micro-environments, their respirational risks, and dysfunctions amid exposed working cohorts.

Leather tanneries are known for chemical laden work environments and pulmonic complaints among workers. This study presents an analysis of tannery micro-environments emphasizing on size-based variation in composition of particulate matter and consequent respiratory dysfunctions. Qualitative (FTIR, SEM-EDX) and quantitative assessment (elemental composition, carbon forms) of PM10 and 2.5 has been employed. For lung function evaluation of workforce, spirometry with ATS proprieties was used. The peak concentrations of both PM10 and 2.5 have been found at PU, FU, and B&S. The LTCR for only Cr is high for both PM2.5 and PM10. HQ was high for Al, Cr, and Mn for both PM sizes. The maximum organic and secondary organic carbon in PM10 was found at FU and in PM2.5 at PU. The varied PM composition included carbohydrate (B&S, WMO), ether (S&S, P&S) and hydroxyl (B&S, S&S, P&S), proteins, polyenes, vinyl groups (S&S, P&S, FU), alcohols (PU and FU), and aldehyde present at PU. These results were armored by high organic and total carbon concentrations for the same sites. Therefore, PM are classified into biogenic (carbonaceous: microbial and animal remains) from PU and WMO, incidental (industrial, mixt physico-chemical character) from PU, FU, WMO, B&S and P&S, and geogenic (crustal mineral dust) from RHT, B&S, PU, and P&S. Furthermore, increase in metal concentrations in PM10 (Cr, Mn, Co, Ni, V, As, Be, Ba, and Cd) and PM2.5 (As, Pb) while TC, OC, and SOC in PM2.5 caused depreciation overall lung function. The exposure to biogenic and incidental PM nature are key cause of pulmonic dysfunction.

Structural modification and strategies for the enhanced doxorubicin drug delivery.

Doxorubicin belongs to the anthracycline chemical class of the drug and is one of the widely used anticancer drugs. The common side effects of doxorubicin include vomiting, hair loss, rashes to serious side-effects such as irreversible cardiotoxicity, and drug-induced leukemia. This led many researchers around the globe to develop methods aimed to achieve higher efficacy and lower toxicity for doxorubicin. The present review article provides a detailed account of the design strategies i.e., chemical modifications and conjugate formation adopted by various research groups to minimize the side effects without compromising with the significant anticancer profile of the drug doxorubicin. Chemical modification of the drug includes alteration at C4' hydroxyl and C3' amine groups present in the sugar part. The pH-sensitive drug delivery system is covered highlighting use of theranostic tantalum oxide to the traditional approach of conjugating with acyl hydrazine and thiourea. Methods adopted to increase the bioavailability of the drugs inside the cancer cells viz., conjugation with humanized monoclonal antibody and other peptides along with their promising results are also discussed. The review further discusses works from recent years comprising of different nanoforms of doxorubicin for the targeted delivery of drugs inside the tumor cells. Few of the articles targeting nucleus or mitochondria as one of the effective cancer treatments are reported. The brain is inaccessible to the drug and it was modified through galactoxyloglucan-modified gold nanocarrier or conjugated with lactoferrin with enhanced permeability through the blood-brain barrier. Prodrug has particularly been used to target tumor tissues without affecting other tissue organs. The present review article offer clear advantages of one method over another adopted to target the cancer cells and may provide an insight for the researchers working in this area.

Rational drug design strategies for the development of promising multi-target directed indole hybrids as Anti-Alzheimer agents.

Alzheimer's disease (AD) is a neurological disorder that leads to dementia i.e., progressive memory loss accompanied with worsening of thinking ability of an individual. The cause of AD is not fully understood but it progresses with age where brain cells gradually die over time. According to the World Health Organization (WHO), currently 50 million people worldwide are affected by dementia and 60-70% of the cases belong to AD. Cumulative research over the past few decades have shown that molecules that act at a single target possess limited efficacy since these investigational drugs are not able to act against complex pathologies and thus do not provide permanent cure. Designing of multi-target directed ligands (MTDLs) appears to be more beneficial and a rational approach to treat chronic complex diseases including neurodegenerative diseases. Recently, MTDLs are being extensively researched by the medicinal chemists for the development of drugs for the treatment of various multifactorial diseases. Indole is one of the privileged scaffolds which is considered as an essential mediator between the gut-brain axis because of its neuroprotective, anti-inflammatory, ß-amyloid anti-aggregation and antioxidant activities. Herein, we have reviewed the potential of some indole-hybrids acting at multiple targets in the pathogenesis of AD. We have reviewed research articles from the year 2014-2021 from various scientific databases and highlighted the synthetic strategies, mechanisms of neuroprotection, toxicity, structure activity relationships and molecular docking studies of various indole-hybrid derivatives. This literature review of published data on indole derivatives indicated that developing indole hybrids have improved the pharmacokinetic profile with lower toxicity, provided synergistic effect, helped to develop more potent compounds and prevented drug-drug interactions. It is evident that this class of compounds have potential to inhibit multiple enzymes targets involved in the pathogenesis of AD and therefore indole hybrids as MTDLs may play an important role in the development of anti-AD molecules.

Effect of Curcuma longa on glycemia, neuropathic sensation and advanced glycation end product in diabetic patients.

Diabetes is a chronic disorder affecting a large number of people throughout the world. According to the American Diabetes Association, overeating is the major diet-related risk factor for type 2 diabetes. To ensure the efficacy of C. longa. in the improvement of glycemic control, neuropathic sensation, and reduction in the formation of advanced glycation end products 90 people that meet inclusion criteria were divided into 2 groups, the control group was only given antidiabetic drugs without C. longa supplement and the treatment group were given C. longa supplement as well as recommended hypoglycemic drugs for 120 days. Results reveal that in all combinations of antidiabetic medicine the addition of curcumin has significantly reduced the level of hemoglobin A1C as compared to the control group. Similarly, there has been a significant reduction in the formation of advanced glycation end products at the end of the study. While a significant improvement in neuropathic sensation has also been observed. Hence it may be concluded that C. longa can be efficiently used in chronic patients with diabetes as a supplement to manage the symptoms and complications of type II diabetes.

Fabrication of graphene oxide coated quartz filter paper for enhanced adsorption of particulate matter.

Airborne particulate matter has become an emerging issue globally due to environmental degradation and the health risk it causes. Volatilization of weakly adsorbed particles onto quartz filter paper (QFP) limits its performance. The adsorption of particulate matter (PM10) onto QFP coated with different concentrations of graphene oxide (GO) was investigated to enhance the adsorption potential. Hummer's method was adopted to synthesize GO. QFPs were coated with different concentrations of GO using a spin coating technique to optimize the result. The morphology and microstructure of GO-QFP were characterized by various experimental techniques, like XRD, FTIR, EDX, and SEM. GO showed considerable affinity to aerosol particles for GO-QFP weighing 5 mg/ml, whereas adsorption of the coated samples before and after was significantly reduced. The high affinity to aerosol particles was due to dominated π-π interactions and the grooved regions formed on the GO layer. It was considered that the high surface to volume ratio of GO-QFP improves the adsorptive property of the QF and consequently enhances the performance of the filter paper.

Prediction of Clearance and Dose of Midazolam in Preterm and Term Neonates: A Comparative Study Between Allometric Scaling and Physiologically Based Pharmacokinetic Modeling.

Children are not small adults because besides size there are subtle physiological and biochemical differences between children and adults. Like adults, children also require medicine for the management or cure for the underlying diseases. To select a right dose in children, pharmacokinetic (PK) information is warranted. However, in many instances, a PK study in neonates and infants may not be possible. Therefore, various methods are used to predict PK parameters in this group of population, and these predicted parameters may help to calculate a safe dose for the very young children. Allometry is widely used for the prediction of PK parameters in children and subsequently one can predict dose from these predicted PK parameters. Physiologically based pharmacokinetic modeling (PBPK) has also become a useful tool to achieve these goals. Therefore, the objective of this study was to compare the predictive performance of allometry and PBPK for a test compound, midazolam in preterm, and term neonates. In this study, there were 5 preterm neonates (gestational age ranging from 34 to 37 weeks) and 5 term neonates (gestational age ranging from 38 to 41 weeks). PBPK modeling was performed using PK-Sim 6.0 and clearance, as well as midazolam dose in neonates was predicted. Clearance and midazolam dose in neonates was also predicted by allometric scaling. In this study, the allometric exponents for the prediction of midazolam clearance in preterm neonates and term neonates were 1.2 and 1.1, respectively. Similarly, for the prediction of midazolam neonatal dose, the exponent of allometry was either 0.9 or 1.0. The predicted midazolam clearance and dose by both methods were then compared with observed midazolam clearance and dose in neonates. The results of the study showed a slightly better prediction of midazolam clearance in neonates by PBPK than allometric scaling. However, the projected dose of midazolam in neonates was comparable between the 2 methods. Overall, it was noted that both PBPK and allometric model can be used to predict clearance and dose of midazolam in neonates.

Temporal characteristics of aerosol optical properties over the glacier region of northern Pakistan.

Glacier melting due to light-absorbing aerosol has become a growing issue in recent decades. The emphasis of this study is to examine aerosol loadings over the high mountain glacier region of northern Pakistan between 2004 and 2016, with sources including local emissions and long-range transported pollution. Optical properties of aerosols were seasonally analyzed over the glacier region (35-36.5°N; 74.5-77.5°E) along with three selected sites (Gilgit, Skardu, and Diamar) based on the Ozone Monitoring Instrument (OMI). The aerosol sub-type profile was analyzed with Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO). Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model was used to understand the origin of air masses arriving in the study region. The highest values of aerosol optical depth (AOD) and single scattering albedo (SSA) occurred during spring, whereas aerosol index (AI) and absorption AOD (AAOD) exhibited maximum values in winter and summer, respectively. The minimum values of AOD, AI, AAOD, and SSA occurred in winter, autumn, winter, and autumn, respectively. The results revealed that in spring and summer the prominent aerosols were dust, whereas, in autumn and winter, anthropogenic aerosols were prominent. Trend analysis showed that AI, AOD, and AAOD increased at the rate of 0.005, 0.006, and 0.0001 yr-1, respectively, while SSA decreased at the rate of 0.0002 yr-1. This is suggestive of the enhancement in aerosol types over the region with time that accelerates melting of ice. CALIPSO data indicate that the regional aerosol was mostly comprised of sub-types categorized as dust, polluted dust, smoke, and clean continental. The types of aerosols defined by OMI were in good agreement with CALIPSO retrievals. Analysis of the National Oceanic and Atmospheric Administration Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model revealed that air parcels arriving at the glacier region stemmed from different source sites.

Isolation, structure elucidation and antibacterial activity of methyl-4,8-dimethylundecanate from the marine actinobacterium Streptomyces albogriseolus ECR64.

Around 120 actinobacterial colonies were isolated from various regions of marine East coast region of Tamil Nadu, India. Among them, 33 were morphologically distinct and they were preliminarily screened for their antibacterial activity against Pseudomonas fluorescens, Vibrio cholerae, V. parahaemolyticus, V. alginolyticus, and Aeromonas hydrophila by cross-streak plate technique. Among the isolated, the isolate ECR64 exhibited maximum zone of inhibition against fish pathogenic bacteria. The crude bioactive compounds were extracted from the isolate ECR64 using different organic solvents which exhibited maximum antibacterial activity. Separation and purification of the bioactive compounds were made by column chromatography which yielded 27 fractions and were re-chromatographed to obtain the active compound. Ultra violet (UV), Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectral studies were used to predict the structure of the active compound which was identified as methyl-4,8-dimethylundecanate. The potential isolate ECR64 was identified as Streptomyces albogriseolus by phylogenetic, phenotypic and genotypic (16S rRNA gene sequence) analyses. The identified compound methyl-4,8-dimethylundecanate can be used as potential and alternative drug in disease management of aquaculture.

Burden of Tobacco in Pakistan: Findings From Global Adult Tobacco Survey 2014.

Introduction: The Global Adult Tobacco Survey (GATS) is the global standard for systematically monitoring adult tobacco use and tracking key tobacco control indicators. Methods: Using a multistage stratified cluster design, 9856 households were sampled, and one individual was randomly selected from each household. Standard GATS questionnaire was used to collect information on tobacco use, cessation, second-hand smoke, knowledge, attitudes, and perceptions. Data were analyzed per standard GATS protocol. Results: Of 9856 individuals, 7831 individuals completed the interview. The response rate was 81%. Overall, 19.1% adults were currently using tobacco products and among them, 12.4% smoked tobacco, and 7.7% smokeless tobacco. Exposure to second-hand smoke was seen in 86% in a restaurant while it was 76% on public transportation. A total of 24.7% smokers made a quit attempt in the past 12 months. Anticigarette smoking information was observed by 37.7% adults, while 29.7% current smokers thought about quitting after reading health warning labels on cigarette packages. Most (85%) adults favored no smoking in public places, and 74.8% favored increasing taxes on tobacco products. Current cigarette smokers spent Pakistani Rupees 767.3 per month (7.78 USD) on manufactured cigarettes and consumed 4500 cigarette sticks (225 packs) annually. Conclusions: Besides 19.1% tobacco users, the majority (86%) were exposed to second-hand smoke at public places indicating that ban on tobacco use in public places is not being followed. A quarter of current smokers wants to quit smoking who may be provided assistance to reduce tobacco burden. Implications: This study provides national-level data about tobacco use and its burden and also indicates weak implantation of tobacco control laws. There is need to devise a strategy for proper implementation of these laws to reduce the tobacco burden in the country.

Characterization of aerosol optical properties using multiple clustering techniques over Zanjan, Iran, during 2010-2013.

Discrimination of aerosol types is very important, because different aerosols are created from diverse sources having different chemical, physical, and optical properties. In the present study, we have analyzed the seasonal classification of aerosol types by multiple clustering techniques, using AERosol Robotic NETwork (AERONET) data during 2010-2013 over Zanjan, Iran. We found that aerosol optical depth (AOD) showed pronounced seasonal variations of a summer high and winter low. Conversely, the values of the Angstrom exponent (AE) in winter and fall were higher than in spring and summer, which confirmed the presence of fine particles, while the low value of AE in the summer and spring represented the existence of coarse particles. Single Scattering Albedo (SSA) variations revealed the presence of scattering aerosols like dust in spring, summer, and fall while the dominance of absorbing-type aerosols in winter were also observed. The influence of local anthropogenic activities has caused a higher concentration of fine aerosols, and a higher fine mode fraction (FMF) of AOD in winter was recorded. Classification of aerosol types was carried out by analyzing different aerosol properties such as AOD versus AE, extinction Angstrom exponent (EAE) versus SSA, EAE versus absorption Angstrom exponent (AAE), FMF AOD versus EAE, and SSA versus FMF AOD. The analysis revealed the presence of dust and polluted dust in spring, summer, and fall in the atmosphere of Zanjan. Urban/industrial aerosols were available in all seasons, especially in fall and winter. The mixed aerosols existed in all seasons over the study location; however, no biomass burning aerosols were found. The Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) aerosol subtype profiles showed the dominance of dust and polluted dust in spring and summer. However, the presence of polluted dust and industrial smoke during fall and winter were also noted over the study site.

Neutrophil extracellular traps in patients with pulmonary tuberculosis.

Tuberculosis is a devastating infectious disease causing many deaths worldwide. Recent investigations have implicated neutrophil extracellular traps (NETs) in the host response to tuberculosis. The aim of the current study was to obtain evidence for NETs release in the circulation during human tuberculosis. For this we measured the plasma concentrations of nucleosomes in conjunction with neutrophil elastase, in 64 patients with active pulmonary tuberculosis and 32 healthy controls. Patients with active tuberculosis had elevated plasma levels of nucleosomes and elastase when compared with local healthy blood donors. Furthermore nucleosome and elastase levels showed a positive correlation. These findings provide the first evidence for the release of NETs in the circulation of patients with active pulmonary tuberculosis.

Long-term (2007-2013) analysis of aerosol optical properties over four locations in the Indo-Gangetic plains: erratum.

The authors regret the incomplete acknowledgment in Appl. Opt.55, 6199 (2016)APOPAI0003-693510.1364/AO.55.006199.

Weak two-photon absorption applied to the rapid prototyping of cell scaffolds.

Two-photon polymerization (TPP) has been employed to generate deep structures using the biocompatible and optically transparent monomer ethoxylated bisphenol A dimethacrylate (EO=6) (EBPADMA) and 4, 4'-Bis(diethylamino)benzophenon as the photoinitiator. The two-photon absorption cross section of the initiator was measured to be 1 GM (1 GM=1×10(-50) cm(4) s photon(-1)) in EBPADMA. Here we have explored a weak absorption regime whereby deep structures (∼300 µm) can be generated in a single pass. This allows rapid fabrication of structures suitable for cell scaffolds where the length scales are small, ∼10 µm, but are required over long ranges, ∼cm. The dependence of the TPP properties on the writing power, speed, exposure time and NA, of the focusing lens were studied in detail. Diffraction calculations for the focusing optics employed show that spherical aberration plays a significant role in determining the feature sizes achieved.

Long-term (2007-2013) analysis of aerosol optical properties over four locations in the Indo-Gangetic plains.

The emphasis of the present work lies on the examination of the distribution and spectral behavior of the optical properties of atmospheric aerosols in the Indo-Gangetic plains (IGP). Measurements were performed using an AErosol RObotic NETwork (AERONET) Sun photometer at four sites (Karachi, Lahore, Jaipur, and Kanpur) with different aerosol environments during the period 2007-2013. The aerosol optical depth (AOD) and Ångström exponent (α) were measured, and the results revealed a high AOD with a low α value over Karachi and Jaipur in July, while a high AOD with a high α value was reported over Lahore and Kanpur during October and December. The pattern of the aerosol volume size distribution (VSD) was similar across all four sites, with a prominent peak in coarse mode at a radius of 4.0-5.0 µm, and in fine mode at a radius of 0.1-4.0 µm, for all seasons. On the other hand, during the winter months, the fine-mode peaks were comparable to the coarse mode, which was not the case during the other seasons. The single scattering albedo (SSA) was found to be strongly wavelength-dependent during all seasons and for all sites, with the exception of Kanpur, where the SSA decreases with increasing wavelength during winter and post-monsoon. It was found that the phase function of the atmospheric aerosol was high at a small angle and stable around a scattering angle of 90°-180° at all sites and during all seasons. Spectral variation of the asymmetry parameter (ASY) revealed a decreasing trend with increasing wavelength, and this decreasing trend was more pronounced during the summer, winter, and post-monsoon as compared to pre-monsoon. Furthermore, extensive measurements suggest that both real (RRI) and imaginary (IRI) parts of the refractive index (RI) show contrasting spectral behavior during all seasons. Finally, the analysis of the National Oceanic and Atmospheric Administration hybrid single particle Lagrangian integrated trajectory model back trajectory revealed that the seasonal variation in aerosol types was influenced by a contribution of air masses from multiple source locations.

Native gallium adatoms discovered on atomically-smooth gallium nitride surfaces at low temperature.

In advanced compound semiconductor devices, such as in quantum dot and quantum well systems, detailed atomic configurations at the growth surfaces are vital in determining the structural and electronic properties. Therefore, it is important to investigate the surface reconstructions in order to make further technological advancements. Usually, conventional semiconductor surfaces (e.g., arsenides, phosphides, and antimonides) are highly reactive due to the existence of a high density of group V (anion) surface dangling bonds. However, in the case of nitrides, group III rich growth conditions in molecular beam epitaxy are usually preferred leading to group III (Ga)-rich surfaces. Here, we use low-temperature scanning tunneling microscopy to reveal a uniform distribution of native gallium adatoms with a density of 0.3%-0.5% of a monolayer on the clean, as-grown surface of nitrogen polar GaN(0001̅) having the centered 6 × 12 reconstruction. Unseen at room temperature, these Ga adatoms are strongly bound to the surface but move with an extremely low surface diffusion barrier and a high density saturation coverage in thermodynamic equilibrium with Ga droplets. Furthermore, the Ga adatoms reveal an intrinsic surface chirality and an asymmetric site occupation. These observations can have important impacts in the understanding of gallium nitride surfaces.

Reverse capillary flow of condensed water through aligned multiwalled carbon nanotubes.

Molecular transport through nanopores has recently received considerable attention as a result of advances in nanofabrication and nanomaterial synthesis technologies. Surprisingly, water transport investigations through carbon nanochannels resulted in two contradicting observations: extremely fast transport or rejection of water molecules. In this paper, we elucidate the mechanism of impeded water vapor transport through the interstitial space of aligned multiwalled carbon nanotubes (aligned-MWCNTs)--capillary condensation, agglomeration, reverse capillary flow, and removal by superhydrophobicity at the tip of the nanotubes. The origin of separation comes from the water's phase change from gas to liquid, followed by reverse capillary flow. First, the saturation water vapor pressure is decreased in a confined space, which is favorable for the phase change of incoming water vapor into liquid drops. Once continuous water meniscus is formed between the nanotubes by the adsoprtion and agglomeration of water molecules, a high reverse Laplace pressure is induced in the mushroom-shaped liquid meniscus at the entry region of the aligned-MWCNTs. The reverse Laplace pressure can be significantly enhanced by decreasing the pore size. Finally, the droplets pushed backward by the reverse Laplace pressure can be removed by superhydrophobicity at the tip of the aligned-MWCNTs. The analytical analysis was also supported by experiments carried out using 4 mm-long aligned-MWCNTs with different intertube distances. The water rejection rate and the separation factor increased as the intertube distance decreased, resulting in 90% and 10, respectively, at an intertube distance of 4 nm. This mechanism and nanotube membrane may be useful for energy-efficient water vapor separation and dehumidification.

Expression of inhibitory regulators of innate immunity in patients with active tuberculosis.

BACKGROUND: Tuberculosis (TB) is an important cause of morbidity and mortality worldwide. Toll-like-receptors (TLRs) are important for the recognition of the causative agent Mycobacterium tuberculosis. Negative regulation of TLRs is necessary to control deleterious inflammatory damage, but could provide a means of immune evasion by M. tuberculosis as well. METHODS: To obtain insight in the extent of expression of inhibitory regulators of immunity in patients with active TB, peripheral-blood-mononuclear-cells (PBMCs) and plasma were obtained from 54 TB patients and 29 healthy blood donors from Chittagong, Bangladesh. Bilateral alveolar macrophages were obtained from an infected versus a contralateral normal lung segment of 9 patients. Statistical analyses were performed using Mann-Whitney U and Wilcoxon matched pairs testing. Correlations were calculated using the Spearman rho test. RESULTS: PBMCs harvested from TB patients demonstrated increased mRNA expression of IL-1-receptor-associated-kinase-M, suppressor-of-cytokine-signalling-3 and Toll-interacting-protein. Flow cytometry revealed enhanced expression of IL-1-receptor-like-1 (ST2) on lymphocytes. Plasma soluble ST2 was elevated in patients with TB and correlated with established TB biomarkers, most strongly with soluble interleukin-2 receptor subunit α and interleukin-8. Alveolar macrophage mRNA expression of negative TLR regulators did not differ between the infected and contralateral lung side. CONCLUSION: These results show enhanced expression of distinct negative regulators of innate immunity in PBMCs of patients with TB and identify plasma soluble ST2 as a potential novel biomarker for TB disease activity.