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In situ instrumentation that can detect amino acids at parts-per-billion concentration levels and distinguish an enantiomeric excess of either d- or l-amino acids is vital for future robotic life-d...

In this study, nano-sized barium titanate powder was applied for the first time to polyester woven fabrics by knife coating at three different concentration rates. Some physical (thickness, mass per unit area, bending rigidity, air permeability and tear strength) properties, electromagnetic shielding efficiency and solar (transmittance, reflectance) properties of samples were presented. The samples were also characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. Electromagnetic shielding effectiveness of the fabrics was determined according to the ASTM D4935-10 standard by using a coaxial transmission line measurement technique in the frequency range of 15–3000 MHz. The solar properties were measured according to EN14500 standard using a UV/VIS/NIR spectrophotometer and results were calculated according to EN 410 standard. Results revealed that the electromagnetic shielding effectiveness and solar reflectance property of samples improved with increasing barium titanate concentration.

Depolanmış ürünlerdeki böceklerle mücadele oldukça önemlidir. Sitophilus granarius (Linnaeus, 1758) (Coleoptera: Curculionidae) ve Tribolium castaneum (Herbst, 1797) (Coleoptera: Tenebrionidea) depolanmış ürünlerde zarar meydana getiren önemli iki zararlı böcek türüdür. Depolanmış ürünlerdeki zararlılarla mücadelede kullanılabilecek alternatif ilaçlara ise her geçen gün ihtiyaç artmaktadır. Bu çalışmada, Achillea phrygia Boiss. et Bal. (Compositae), Prangos ferulacea (L.) Lindl. (Apiaceae) ve Salvia wiedemannii Boiss. (Lamiaceae) bitkilerinden elde edilen bitki ekstraktlarının, S. granarius ve T. castaneum ile mücadelede kullanılabilirlikleri araştırılmıştır. 72 saat sonunda, S. garanarius üzerinde test edilen bitkiler arasında en yüksek kontak aktiviteyi sırasıyla %74 ile P. ferulaceae hekzan, %71 ile A. phrygia methanol ekstraktı göstermiştir. T. castaneum üzerinde en yüksek aktiviteyi ise 72 saat sonunda %42 ile A. phrygia etil asetat ekstraktı göstermiştir. Bitki ekstraktları ile yapılan davranışsal etki çalışmalarında ise S. granarius üzerindeki en yüksek repellent aktivite 24. saat sonunda P. ferulaceae etil asetat ekstraktından (%52) elde edilmiştir. Bitki ekstraktlarının tamamı T. castaneum üzerinde yüksek oranda repellent etki göstermiştir.

Multimaterial fibers engineered to integrate glasses, metals, semiconductors, and composites found applications in ubiquitous sensing, biomedicine, and robotics. The longitudinal symmetry typical of fibers, however, limits the density of functional interfaces with fiber-based devices. Here, thermal drawing and photolithography are combined to produce a scalable method for deterministically breaking axial symmetry within multimaterial fibers. Our approach harnesses a two-step polymerization in thiol–epoxy and thiol–ene photopolymer networks to create a photoresist compatible with high-throughput thermal drawing in atmospheric conditions. This, in turn, delivers meters of fiber that can be patterned along the length increasing the density of functional points. This approach may advance applications of fiber-based devices in distributed sensors, large area optoelectronic devices, and smart textiles., Thermally drawable photoresist based on thiol−epoxy/thiol−ene network enables high-throughput fabrication of hundreds of meters of longitudinally patternable multimaterial fibers.

The molecules feeding life's emergence are thought to have been provided through the hydrothermal interactions of convecting carbonic ocean waters with minerals comprising the early Hadean oceanic crust. Few laboratory experiments have simulated ancient hydrothermal conditions to test this conjecture. We used the JPL hydrothermal flow reactor to investigate CO

Lower photonic conversion efficiency along with complexity of fabrication are the primary constrains for cost effective thin film solar cell production. In this work, a planar single junction structure of thin film solar cell made with two different active materials is studied, which can take care of the mentioned problems. The active materials were selected based on different parameters like band gap energy, contact potential, lattice mismatch and cost effectiveness. Simulation shows that optical absorption along with photonic conversion efficiency varies due to change in position, thickness and doping concentration of active material and so these parameters are optimized accordingly. Here an interface layer of Gallium Arsenide (GaAs) is added to the thin film Silicon (Si) layer. Our optimized Si-GaAs based thin film solar cell yields a short circuit current density of 27.51 mA/cm2 with conversion efficiency of 13.71% having a fill factor of 0.81 under AM1.5G for a typical thin film solar cell of total thickness 2 µm out of which 80% is crystalline Silicon (1.6 µm thick) and 20% is Gallium arsenide (0.4 µm thick). Thus, a simple structure with improved conversion efficiency is proposed.

Aim & Background: It was proposed that the differences in erythrocyte membrane protein contents—especially band 4—take a role in the serious anemia related to interferon plus ribavirin (I/R). The aim of this study is to evaluate whether the erythrocyte membrane protein contents predict anemia related to I/R or not. Methods: 180 mcg interferon α 2a once a week and weight adjusted ribavirin daily were given for 48 weeks to fifty patients with chronic hepatitis C. It was diagnosed as anemia when haemoglobin concentration was

Besides maintaining a physical barrier with adherens junctional (AJ) and tight junctional proteins, airway epithelial cells have important roles in modulating the inflammatory processes of allergic asthma. E-cadherin and beta-catenin are the key AJ proteins that are involved in airway remodeling. Various mediators such as transforming growth factor-beta (TGF-beta), epidermal growth factor (EGF), fibroblast growth factor (FGF), platelet derived growth factor (PDGF), insulin-like growth factor (IGF), tumor necrosis factor-alpha (TNF-alpha) and angiogenic factors, such as vascular endothelial growth factor (VEGF), are released by the airway epithelium in allergic asthma. The signaling pathways activated by these growth factors trigger epithelial-mesenchymal transition (EMT), which contributes to fibrosis and subsequent downregulation of E-cadherin. The present study used a mouse asthma model to investigate the effects of anti-VEGF, anti-TNF and corticosteroid therapies on growth factor and E-cadherin/beta-catenin expression. The study used 38 male BALB/c mice, divided into 5 groups. A chronic mouse asthma model was created by treating 4 of the groups with inhaled and intraperitoneal ovalbumin (n= 8 per group). Saline, anti-TNF-alpha (etanercept), anti-VEGF (bevacizumab) or a corticosteroid (dexamethasone) were applied to each group by intraperitoneal injection. No medication was administered to the control group (n=6). Immunohistochemistry for E-cadherin, beta-catenin and growth factors was performed on lung tissues and protein expression levels assessed using H-scores. Statistically significant differences were observed in E-cadherin, beta-catenin, EGF, FG, and PFGF (P0.005). All treatment groups had reduced TGF-beta, PDGF and FGF H-scores in comparison with the untreated asthma group (P=0.001). The EGF and IGF levels were not significantly different between the untreated asthmatic and non-asthmatic controls. The results suggested that anti-VEGF and TNF-alpha inhibition treatments are effective in decreasing growth factors, in a similar manner to conventional corticosteroid treatments. Anti-VEGF and TNF inhibition therapy may be an effective treatment for remodeling in asthma while offering an alternative therapeutic option to steroid protective agents. The data suggested that anti-VEGF treatment offered greater restoration of the epithelial barrier than both anti-TNF-alpha and corticosteroid treatment.

We describe the demographic, clinical, and laboratory characteristics of children with COVID 19 in comparison with those of not-laboratory-confirmed cases. We conducted a cross-sectional study on the epidemiological, clinical, radiological, and laboratory characteristics, and outcome of 422 children (aged 0–18 years) with suspected and confirmed COVID 19 admitted to the pediatric emergency department from March 23rd to July 23rd, 2020. Of the 422 children with suspected COVID-19 included in this study, COVID-19 was PCR-confirmed in 78 (18.4%). Fever (51.2%) and cough (43.5%) were the most prominent symptoms in children with confirmed cases. The clinical status of the patients with confirmed COVID-19 was significantly milder than that of those with suspected COVID-19. The proportion of COVID-19 pneumonia cases was 44.4%, 5.5%, 18.7%, and 8.5% for the age groups of ≤ 1, 2–6, 7–12, and ≥ 12 years, respectively. Of the 422 children, 128 (30.3%) underwent nasopharyngeal PCR testing for other respiratory viral pathogens; 21 (16.4%) were infected with viral pathogens other than severe acute respiratory syndrome-related coronavirus-2. Only one patient (4.7%) with confirmed COVID-19 had coinfection with respiratory syncytial virus and rhinovirus. The areas under the receiver-operating characteristics curves were 0.812 for WBCs, 0.752 for neutrophils, 0.717 for lactate dehydrogenase, and 0.708 for lymphocyte for predicting COVID-19 (p ≤ 0.001). Fever and cough or other clinical symptoms or signs should not be considered hallmarks of COVID 19. In this study, the WBC, neutrophil, and lymphocyte counts were predictive of COVID-19 positivity.

Investigating the binding interaction of small molecules to large ligands is a compelling task for the field of drug development, as well as agro-biotechnology, since a common trait of drugs and toxins is often a low molecular weight (MW). Here, we improve the limit of detection of the Interferometric Reflectance Imaging Sensor (IRIS), a label-free, highly multiplexed biosensor, to perform small-molecule screening. In this work, characterization of small molecules binding to immobilized probes in a microarray format is demonstrated, with a limit of detection of 1 pg/mm2 in mass density. First, as a proof of concept to show the impact of spatial and temporal averaging on the system noise, detection of biotin (MW = 244.3 Da) binding to a streptavidin-functionalized chip is performed and the parameters are tuned to achieve maximum signal-to-noise ratio (SNR ≈ 34). The optimized system is then applied to the screening of a 20-multiplexed antibody chip against fumonisin B1 (MW = 721.8 Da), a mycotoxin found in cereal grains. The simultaneously recorded binding curves yield an SNR ≈ 8. Five out of twenty antibodies are also screened against the toxin in a lateral flow assay, obtaining consistent results. With the demonstrated noise characteristics, further sensitivity improvements are expected with the advancement of camera sensor technology.

Enhancement of optical to electrical conversion is vital for improving the efficiency of any solar cell. In recent years, use of thin films instead of bulk wafers has resulted in a huge reduction of production cost, and as such, efficiency enhancement of thin-film solar cells is considered in this study. Though this enhancement depends on several factors, most significant among them is the increase in light absorption within the active material of the solar cell. In this work, various types of grating structures on both sides of active solar cell material for light trapping are studied in detail, and a new type of arrangement of optimized grating structure that significantly improves the light absorption is selected. Enhancement of light absorption for change in dielectric material of the grating structure without changing the active material is also observed. Along with structural optimization, simulated electrical characterization of the samples was also performed, which yields a short-circuit current density of 29.27 m A / c m 2 with conversion efficiency of 14.51%, having a fill factor of 0.83 for a typical ultrathin layer of active material of thickness 2 µm. This is quite significant because typical cells of this category have much lesser conversion efficiency.

Atmospheric water adsorbed onto clay mineral surfaces, of smectite group minerals in particular, can contaminate hydrogen released from structural hydroxyl groups during hydrogen-isotope analysis. Interlayer cation composition and cation hydration enthalpy, in particular, can affect the magnitude of this excess hydrogen yield and hence the hydrogen isotope composition (δ2H) of smectites. To evaluate this problem, δ2H of different cation-saturated (Ca2+, Na+, K+), dried forms of six smectite standards from the Clay Minerals Society Source Clays were measured using a modified sample drying and on-line High-Temperature-Conversion-Elemental-Analysis (TCEA) Continuous-Flow-Isotope-Ratio-Mass-Spectrometry (CF-IRMS) protocol. More negative interlayer cation hydration enthalpies (Ca2+ > Na+ > K+) led to higher residual adsorbed water contents, which produced poorer δ2H reproducibility for the determination of smectite hydroxyl hydrogen. The lowest adsorbed water contribution and the most reproducible and possibly accurate δ2H for smectite hydroxyl hydrogen was obtained for K-saturated smectites dried for both 4 and 24 h at 220 °C prior to isotopic analysis and transferred to a “Zero-Blank” autosampler in ≤2.5 min. This approach provided the lowest measurement error for hydroxyl δ2H and facilitated much greater sample throughput than classical methods for smectitic clays. This study proposes a protocol for hydroxyl δ2H determination in smectitic clay minerals, and reveals the effect of H-isotope fractionation of adsorbed water during sample preparation.

The detection of organic molecules that are indicative of past or present biological activity within the Solar System bodies and beyond is a key research area in astrobiology. Mars is of particular interest in this regard because of evidence of a (perhaps transient) warm and wet climate in its past. To date, space missions to Mars have primarily used pyrolysis technique to extract organic compounds from the Martian regolith, but it has not enabled a clear detection of unaltered native Martian organics. The elevated temperatures required for pyrolysis extraction can cause native Martian organics to react with perchlorate salts in the regolith, possibly resulting in the chlorohydrocarbons that have been detected by mass spectrometry, a commonly usedin situtechnique for space applications. Supercritical carbon dioxide (SCCO2) extraction technique is a powerful alternative to pyrolysis that may be capable of extracting and delivering unaltered native organic species to an analyser. In this study, we report the SCCO2extraction of unaltered amino acids (AAs) with simple laboratory analyses of extracts by capillary electrophoresis laser-induced fluorescence (CE/LIF) and liquid chromatography with mass spectrometry (LC/MS) techniques. The extraction efficiencies of several representative AAs using SCCO2with small amounts of pure water (~1–5%) as a co-solvent were determined. Glass beads were used as a model substrate to examine the effects of several experimental parameters and Johnson Space Center (JSC) Mars-1A Martian regolith simulant was used to study the effect of complex matrix on extraction efficiencies. With optimized experimental conditions (75C and 5% of water), extraction efficiencies from doped JSC Mars-1A were found to be ~40% for glycine, alanine and serine and ~10% for lysine. Extraction of native organics from undoped JSC Mars-1A suggests that SCCO2/water solvent system can extract both organics extractable with pure SCCO2and those extractable with pure water. Additionally, species not extracted by either pure SCCO2or pure water were extracted with SCCO2/water solvent. Despite the preliminary nature of this work, it paves the path for more comprehensive extraction studies of astrobiologically relevant samples with thorough analyses of resulting extracts.

Introduction:Cystic fibrosis (CF) is characterized with chronic inflammation with neutrophil and related cytokines in airway secretions. We aimed to measure the levels of neutrophil related inflammatory markers as nitric oxide, IL-8, IL-17, leukotriene B4 and neutrophil elastase as well as e-cadherin in exhaled breath condensate (EBC), and to determine their relation with clinical findings.Methods:We consecutively enrolled cystic fibrosis patients into our clinics between the age of six and eighteen years who could cooperate for exhaled breath condensate to this case-control study (n = 30). the age and sex matched control group (n = 26) was enrolled. Spirometry was performed during the stable period and EBC samples were obtained for measurement of the markers.Results:The mean age of the subjects enrolled was 12.1(4.2) years and 40% were positive forP.Aeruginosain sputum. Subjects who hadP.Aeruginosain sputum cultures had significantly lower FEV1, FVC and FEF 25/75 values compared to the ones withoutP.Aeruginosa(p = 0.002, p = 0.002 and p = 0.005 respectively). EBC neutrophil elastase levels were significantly higher in the CF patients compared to non-CF controls (3.11 4.71 versus 0.90 2.68, p = 0.04). Nitric oxide, IL-17, IL-8, e-cadherin, neutrophil elastase or leukotriene B4 levels in EBC of CF patients were not related toP.Aeruginosas infection, FEV1 levels or hospital admission in the last year.Conclusion:In our study, neutrophil elastase levels in EBC are higher in CF patients compared to non-CF controls. This is independent of acute infection and is evidence to the persistence of neutrophilic lung injury. However, EBC NO, IL-8, IL-17, e-cadherin, neutrophil elastase and leukotriene B4 levels as inflammatory markers, are not correlated with disease progression or clinical findings.

Bacterial infectious diseases are a major threat to human health. Timely and sensitive pathogenic bacteria detection is crucial in identifying the bacterial contaminations and preventing the spread of infectious diseases. Due to limitations of conventional bacteria detection techniques there have been concerted research efforts towards development of new biosensors. Biosensors offering label free, whole bacteria detection are highly desirable over those relying on label based or pathogenic molecular components detection. The major advantage is eliminating the additional time and cost required for labeling or extracting the desired bacterial components. Here, we demonstrate rapid, sensitive and label free E. coli detection utilizing interferometric reflectance imaging enhancement allowing for visualizing individual pathogens captured on the surface. Enabled by our ability to count individual bacteria on a large sensor surface, we demonstrate a limit of detection of 2.2 CFU/ml from a buffer solution with no sample preparation. To the best of our knowledge, this high level of sensitivity for whole E. coli detection is unprecedented in label free biosensing. The specificity of our biosensor is validated by comparing the response to target bacteria E. coli and non target bacteria S. aureus, K. pneumonia and P. aeruginosa. The biosensor performance in tap water also proves that its detection capability is unaffected by the sample complexity. Furthermore, our sensor platform provides high optical magnification imaging and thus validation of recorded detection events as the target bacteria based on morphological characterization. Therefore, our sensitive and label free detection method offers new perspectives for direct bacterial detection in real matrices and clinical samples., 15 pages, 6 figures, 1 table

Bacterial membrane vesicles (MVs) facilitate long-distance delivery of virulence factors crucial for pathogenicity. The entry and trafficking mechanisms of virulence factors inside host cells is recently emerging, however, if bacterial MVs modulate the physicochemical properties of the host lipid membrane remains unknown. Here we reconstitute the interaction of bacterial MV with host cell lipid membranes and quantitatively show that bacterial MV interaction increases the fluidity, dipole potential and elasticity of a biologically relevant multi-component host membrane. The presence of cylindrical lipids such as phosphatidylcholine and phosphatidylinositol and a moderate acyl chain length of C16 helps the MV interaction. While significant binding of bacterial MVs to the raft-like lipid membranes with phase separated regions of the membrane was observed, however, MVs have a preference for binding to the liquid disordered regions of the membrane. Further, the elevated levels of cholesterol tend to hinder the interaction of bacterial MVs. We further quantify the change in excess Gibbs free energy of mixing of bacterial MVs with host lipid membranes driving the modulation of host membrane parameters. The findings may have significant implications on the regulation of host machineries by pathogen through manipulation of host membrane properties.Significance StatementBacterial membrane vesicles (MVs) act as the long-distance delivery tools for virulence factor and thus, directly implicated in host-pathogen interactions and pathogenicity. While the mechanisms of virulence transfer is only recently emerging, however, the interaction of MVs the host cell membrane remains largely unexplored. Whether the MVs interaction can locally modulate the host lipid membrane physicochemical properties (such as fluidity, dipole potential and elasticity) remains unknown. Here, we quantitatively investigate the lipid specificity of E. Coli MV interaction and this results in increase in the fluidity, dipole potential and in-plane elasticity of a biologically relevant multi-component host membrane. The findings could be important for numerous cell-signaling processes as well as downstream events involving membrane-membrane fusion during process of phagosome maturation.

Sensitive and robust in situ chemical analysis of organic biomarkers is essential in the endeavor of finding chemical signatures of life either extinct or extant on our solar system bodies such as Europa, Enceladus, or Titan. Development of new analytical instruments and accompanying methodologies are needed, especially those that are compatible with unknown and diverse samples potentially found on solar system targets and that avoid complexities involved with other wet chemistry techniques (desalting, derivatization and contamination issues, etc.). In this study, we demonstrate that online supercritical fluid extraction and supercritical fluid chromatography with water-saturated CO2 can extract and separate nonpolar analytes of astrobiological interest, such as free fatty acids, polycyclic aromatic hydrocarbons, and polycyclic aromatic compounds containing nitrogen or sulfur. Silica was used as a support material to immobilize aqueous samples during extraction. A C18 stationary phase with an embedded polar functional group and efficient end-capping in combination with water in the mobile phase allowed efficient separation of both free fatty acids and basic compounds. The total analysis time was 30 min, including extraction, equilibration, and separation. Detection was performed with a UV detector and a quadrupole mass spectrometer equipped with electrospray ionization. The method was validated in terms of lower detection limits (0.02–40 μg/L), precision (repeatability 3–13%), relative standard deviation (RSD), intermediate precision 4–26% (RSD), trueness (bias ranging from − 48 to 9%), and retention time shifts (

WOS:000459759500001 In this study, the yellowing behavior of cellulose powders, which is applied to pretreated polyester woven fabrics with concentrations of 100g/kg by knife coating technique, was investigated. After drying process, coated fabrics were cured at different conditions to determine the effects of the curing temperature and time on yellowing behaviors. The yellowness-whiteness of coated fabrics was measured with a spectrophotometer according to ASTM E313. As the curing temperature and time increase, yellowing effect was more observable. However, the effect of temperature increase is found to be more significant than the increase in curing duration in terms of more observed yellowness. In order to investigate the reason of yellowing, cellulose powder samples were heated in drying oven at three different heating temperatures (130 degrees C, 150 degrees C, and 170 degrees C) for three different heating periods (3, 5, and 7 min). Then, thermal gravimetric analysis and Fourier transform infrared spectroscopy analysis of powder samples were performed for each temperature-period combinations. No ring-opening reaction on the cellulose group was found in the Fourier transform infrared spectroscopy analysis. However, the changes in the spectra can be attributed to the chain breakage in the cellulose macromolecules as well as water loss from the molecular structure during the heating process. Microscopic and scanning electron microscopic analysis was carried out to see any surface change on the fiber and coated fabric. There was no detectable surface change on the fiber and coated fabric surface, apart from a color change on the fabric surface.

The analysis of the organic compounds present in the martian regolith is essential for understanding the history and habitability of Mars, as well as studying the signs of possible extant or extinct life. To date, pyrolysis, the only technique that has been used to extract organic compounds from the martian regolith, has not enabled the detection of unaltered native martian organics. The elevated temperatures required for pyrolysis extraction can cause native martian organics to react with perchlorate salts in the regolith and possibly result in the chlorohydrocarbons that have been detected by in situ instruments. Supercritical carbon dioxide (SCCO2) extraction is an alternative to pyrolysis that may be capable of delivering unaltered native organic species to an in situ detector. In this study, we report the SCCO2 extraction of unaltered coronene, a representative polycyclic aromatic hydrocarbon (PAH), from martian regolith simulants, in the presence of 3 parts per thousand (ppth) sodium perchlorate. PAHs are a class of nonpolar molecules of astrobiological interest and are delivered to the martian surface by meteoritic infall. We also determined that the extraction efficiency of coronene was unaffected by the presence of perchlorate on the regolith simulant, and that no sodium perchlorate was extracted by SCCO2. This indicates that SCCO2 extraction can provide de-salted samples that could be directly delivered to a variety of in situ detectors. SCCO2 was also used to extract trace native fluorescent organic compounds from the martian regolith simulant JSC Mars-1, providing further evidence that SCCO2 extraction may provide an alternative to pyrolysis to enable the delivery of unaltered native organic compounds to an in situ detector on a future Mars rover.Biomarkers-Carbon dioxide-In situ measurement-Mars-Search for Mars' organics. Astrobiology 16, 703-714.

Introduction: MYD88 mutations are found in 25% of DLBCL and are associated with an inferior survival. MYD88 is an adapter molecule, forming the core of the Myddosome complex. MYD88 mutations constitutively activate pathways such as NFқB, leading to lymphomagenesis. Essential to the Myddosome-dependent signaling pathway is the recruitment of IRAK4 which complexes with MYD88 to activate downstream effects. Targeting IRAK4 is therefore a rational therapeutic approach in MYD88-mutant lymphomas. First-in-class IRAKIMiDs, novel heterobifunctional degraders that target IRAK4 as well as the IMiD substrates Ikaros and Aiolos to enable the inhibition of both the NFkB and IRF4 pathways activated by MYD88 mutations, demonstrate potent efficacy in MYD88-mutant lymphomas (KTX-475, KTX-582, Walker D et al. AACR 2020). Herein, we compare the activity of IRAKIMiDs to IRAK4 kinase inhibitors and IMiDs alone in MYD88-mutant DLBCL, and evaluate rational combinations of IRAKIMiDs and other active agents in DLBCL for synergy. Methods: MYD88-mutant (n=4) and wild type (n=4) DLBCL cell lines were exposed to a panel of single agents (KTX-475, KTX-582, BAY1830839, CA-4948, CC-220, lenalidomide, pomalidomide, ibrutinib, umbralisib, venetoclax) in order to establish the drug concentration:cytotoxicity effect relationship. Cell viability was assessed using Celltiter-Glo assay at 24-hour intervals. IC50 values were computed. MYD88-mutant DLBCL cells were co-exposed to combinations of KTX-475 with venetoclax, ibrutinib, or umbralisib at concentrations representing their respective IC10-40 in order to determine synergy using the excess over bliss (EOB) method. Venetoclax, ibrutinib, and umbralisib were selected for combinational studies in order to target adverse pathways known to be associated in DLBCL biology. To confirm IRAK4 degradation, western blot and flow cytometry was performed. Apoptosis was evaluated with flow cytometry. Pre-treatment RNA-seq libraries were developed for the purpose of identifying GSEA and mutational analysis to predict response to IRAKIMiDs. Results: Exposure to IRAKIMiDs led to potent activity in MYD88-mutated DLBCL with IC50s in the low nanomolar range. IRAK4 degradation occured in a dose- and time-dependent manner and was observed as early as four hours after exposure. IRAKIMiDs induced superior cytotoxicity compared to two IRAK4 kinase inhibitors, including CA-4948 (Curis), which is currently under clinical investigation for relapsed/refractory NHL, as determined by lower IC50s in all cell lines. IRAKIMiD IC50s were also lower compared to pomalidomide, lenalidomide, and CC-220. KTX-475 was selected for synergy assessments based on IC50 values. Synergy was observed after exposure to KTX-475 in conjunction with venetoclax, ibrutinib, or umbralisib as determined by EOB >0 in the MYD88-mutant OCI-LY10 model, with maximum values peaking at 72-96 hours. After dual drug exposure, IRAK4 degradation was validated by flow cytometry demonstrating that the addition of venetoclax, ibrutinib or umbralisib to KTX-475 did not impair IRAK4 degradation capabilities. RNA-seq interpretation is currently underway. Conclusions: Collectively, our results demonstrate that dual-function degraders targeting both IRAK4 and the IMiD substrates Ikaros and Aiolos can serve as a potential therapeutic option for poor prognosis MYD88-mutant DLBCL. Our data thus far demonstrate improved efficacy of IRAKIMiDs compared to IRAK4 kinase inhibitors or IMiDs alone in vitro, as well as synergy with other active agents in combination regimens. A promising lead IRAKIMiD candidate has been identified, with initiation of a first-in-human clinical trial in B-cell lymphomas planned for 2021. Disclosures Lue: Daiichi Sankyo: Honoraria; AstraZeneca: Speakers Bureau; Astex Pharmaceuticals: Honoraria; Kymera Therapeutics: Honoraria, Research Funding; Kura Oncology: Honoraria. Klaus:Kymera Therapeutics: Current Employment, Current equity holder in publicly-traded company. Kanik:Kymera Therapeutics: Current Employment, Current equity holder in publicly-traded company. McDonald:Kymera Therapeutics: Current Employment, Current equity holder in publicly-traded company. Gollob:Kymera Therapeutics: Current Employment, Current equity holder in publicly-traded company. Walker:Kymera Therapeutics: Current Employment, Current equity holder in publicly-traded company. O'Connor:Kymera Therapeutics: Current equity holder in private company, Honoraria, Membership on an entity's Board of Directors or advisory committees; TG Therapeutics: Current Employment, Current equity holder in publicly-traded company; Servier: Consultancy; Mundipharma: Other: Consulting; Astex Pharmaceuticals: Honoraria, Research Funding; Merck: Research Funding; Nomocan: Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Other: Data Safety Monitoring Committee, Research Funding. Mainolfi:Kymera Therapeutics: Current Employment, Current equity holder in publicly-traded company.

The standard laboratory procedure for determining the antibiotic susceptibility of a pathogen (an antimicrobial susceptibility test, AST) measures the inhibition of growth, and requires several days. This can delay effective therapy and lead to antibiotic overuse and misuse. Recent work (Wei Hou et al, Lab on a Chip 2015) has shown that resistant and susceptible pathogens will have very different gene expression profiles shortly following antibiotic exposure, and that these expression biomarkers may be used to accurately identify the pathogen species, strain and antibiotic susceptibility without growth. We therefore developed an ultrasensitive ‘digital microarray’ for performing rapid & quantitative gene expression analysis as part of a rapid AST. The digital microarray uses plasmonic gold nanorods (GNRs) functionalized with DNA to specifically label each target RNA that binds to the microarray. Each GNR on the array is then individually detected based on its light scattering, with an interferometric microscopy technique called SP- IRIS. Our optimized high-throughput version of SP-IRIS is able to scan a typical array of 500 spots in less than 10 minutes. Due to its single molecule readout, the assay has a limit of detection of less than 1 femtomolar following just 2 hours of incubation. Altogether, digital microarrays are about 10,000-fold more sensitive than fluorescence microarrays, yet maintain all of the strengths of the platform including low cost and high multiplexing. The reproducibility and robustness of the multiplexed assay will next be evaluated with clinically relevant pathogenic strains of E. coli as part of a functional rapid AST.

One model for the emergence of life posits that ancient, low temperature, submarine alkaline hydrothermal vents, partly composed of iron-sulfides, were capable of catalyzing the synthesis of prebiotic organic molecules from CO2, H2 and CH4. Specifically, hydrothermal mackinawite (FeIIS) and greigite (FeIIFeIII2S4) have been highlighted in previous studies as analogs of the active centers of hydrogenase, ferredoxin, acetyl coenzyme-A synthase and carbon monoxide dehydrogenase featured in the biochemistry of certain autotrophic prokaryotes that occupy the base of the evolutionary tree. Despite the proposed importance of iron sulfide minerals and clusters in the synthesis of abiotic organic molecules, the mechanisms for the formation of these sulfides from solution and their preservation under the anoxic and low temperature (below 100 °C) conditions expected in off-axis submarine alkaline vent systems is not well understood ( Bourdoiseau et al., 2011 , Rickard and Luther, 2007 ). To rectify this, single hydrothermal chimneys were precipitated using a unique apparatus to simulate growth at hydrothermal vents of moderate temperature under supposed Hadean ocean-bottom conditions. Iron sulfide phases were observed through Raman spectroscopy at growth temperatures ranging from 40° to 80 °C. Fe(III)-containing mackinawite is confirmed to be present with mackinawite and greigite, supporting an FeIII-mackinawite intermediate mechanism for the transformation of mackinawite to greigite below 100 °C. Raman spectroscopy of the chimneys revealed a maximum yield of greigite at 75 °C. These results suggest abiotic production of catalytically active mackinawite and greigite are possible under early Earth hydrothermal conditions as well as on other wet, rocky worlds geochemically similar to the Earth.

Streszczenie Przestawiono wyniki badań zmiany hydrofobowych właściwości drobnodyspersyjnego wapienia pod wpływem wybranych czynników korozyjnych. Badano dwie frakcje ziarnowe drobnodysper- syjnego wapienia, o średnicy ziaren zgodnie z danymi producenta (Kopalnia Wapienia Czatkowice) wynoszącej odpowiednio: dla mączki wapiennej poniżej 80 um oraz piasku wapiennego z przedziału 100-400 um. Badano również mączką wapienną hydrofobizowaną w kamieniołomie wapieni i margli cementowni w Małogoszczy. Badano materiały surowe oraz hydrofobizowanc za pomocą kwasu stearynowego, preparatu silikonowego oraz preparatu bitumicznego. Jako substancji agresywnych (korodotwórczych) użyto roztworów: kwasu etanowego, zasady amonowej, siarczanu VI sodu. Określono wpływ tych substancji na zmianą nasiąkliwości i ściśliwości badanych materiałów. Miarą nasiąkliwości była zmiana wilgotności materiałów podczas procesu wilgotnego składowania. Ściśli- wość obliczano na podstawie pomiarów deasymetrycznych: gęstości nasypowej swobodnej i upako- wanej, oznaczanych za pomocą cylindra miarowego. Niewielkie zmiany wartości współczynników ściśliwości uzyskane dla materiałów skorodowanych w porównaniu do wartości uzyskanych dla materiałów wyjściowych świadczą o podobnych właściwościach kohezyjnych obu rodzajów mate- riałów. Większość modyfikowanych (hydrofobowych) materiałów po procesie korodowania uzyski- wała gorsze właściwości wodoodporne niż materiały wyjściowe, ale w dalszym ciągu charakte- ryzowała sią wyższym stopniem hydrofobowości niż skorodowane materiały surowe. Dla mączki wapiennej nie uzyskano powtarzalnych wyników, co najprawdopodobniej spowodowane jest większą reaktywnością tego materiału związaną z małą średnicą ziaren. Przeprowadzone badania miały charakter wstępny.

We examine the electrochemical gradients that form across chemical garden membranes and investigate how self-assembling, out-of-equilibrium inorganic precipitates—mimicking in some ways those generated in far-from-equilibrium natural systems—can generate electrochemical energy. Measurements of electrical potential and current were made across membranes precipitated both by injection and solution interface methods in iron-sulfide and iron-hydroxide reaction systems. The battery-like nature of chemical gardens was demonstrated by linking multiple experiments in series which produced sufficient electrical energy to light an external light-emitting diode (LED). This work paves the way for determining relevant properties of geological precipitates that may have played a role in hydrothermal redox chemistry at the origin of life, and materials applications that utilize the electrochemical properties of self-organizing chemical systems.

The preparation and characterization of a novel solid-phase microextraction fiber is reported with application to the determination of pesticides in fruit juice. The fiber was fabricated by electrochemically coating a stainless steel wire with a thin polymeric film of 4-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl) benzenamine. The procedure was initiated in 10 mL of acetonitrile containing 5.5 mg of monomer, 0.1 mol NaClO4, and 0.1 mol LiClO4 by cycling the potential between −0.5 and 1.2 V with a scan rate of 100 mV/sec. The morphology of the fiber surface was examined by scanning electron microscopy and its stability was characterized by thermal gravimetric analysis. The fiber was exposed to headspace extraction of bromopropylate, chlorpyrifos, lambda-cyhalothrin, penconazole, and procymidone prior to the analysis by gas chromatography with an electron capture detector. Operational parameters affecting the extraction efficiency, adsorption and desorption times and temperature, and stirring rate were sc...

COPD is a chronic inflammatory disease which usually resulting from gene-environment interaction and complex, heterogeneous and characterized by exacerbations. NTHi (typeable Haemophilus influenzae) is the major known cause of COPD exacerbations and express sialic acid which contain lipooligosakkarit. There are some claims that Siglec-14, which is one of the sialic acid binding from lectins, increases immune cells of the inflammatory by interacting with the NTHi and causes more frequently to the exacerbations of COPD. In our study, it was aimed to determine relationship between exacerbations and SIGLEC-14 gene polymorphism in patients with COPD. Our study is a prospective comparative case series study which includes healthy controls. 85 COPD patients and for control group 94 healthy which was evaluated by Mersin University of Medicine Faculty Hospital pulmonary clinic with diagnosis of COPD between june 2015-june 2016 where included in our study. These SIGLEC14 genotype of DNA samples from venous blood and plasma were evaluated in Siglec-14 concentration and the patients monitored for exacerbation during a year. In both groups, SIGLEC14 wild / wild polymorphism is dominant, in patients group SIGLEC14 null / null polymorphism was not observed. The patients who have SIGLEC 14 wild / wild number of exacerbations was significantly greater (p = 0.041) than the patients who have SIGLEC14 wild/null genotipe. In adition the number of exacerbations in this group of patients receiving ICS was significantly higher than patients in the SIGLEC14 wild / null genotype (p=0.012). Ultimately, SIGLEC14 wild/wild polymorphism may be a predictor of exacerbations in COPD, but the same can not be said for SIGLEC14 serum levels.

We demonstrate a rice leaf-like hierarchically textured polymer fiber array for anisotropic non-wetting surfaces. To provide superhydrophobicity in addition to the anisotropic behavior, fiber surfaces are spray coated with organically modified silica nanoparticles. The resulting micro/nano hierarchically structured fiber surfaces demonstrate anisotropic non- wetting properties. We designed various fiber architectures for droplet transportation, mixing, and guiding exploiting the scalability of the fiber texture during thermal drawing; optional nanoparticle surface modification; and inherent flexibility of the fibers.

Biological nanoparticles such as viruses and exosomes are important biomarkers for a range of medical conditions, from infectious diseases to cancer. Biological sensors that detect whole viruses and exosomes with high specificity, yet without additional labeling, are promising because they reduce the complexity of sample preparation and may improve measurement quality by retaining information about nanoscale physical structure of the bio-nanoparticle (BNP). Towards this end, a variety of BNP biosensor technologies have been developed, several of which are capable of enumerating the precise number of detected viruses or exosomes and analyzing physical properties of each individual particle. Optical imaging techniques are promising candidates among broad range of label-free nanoparticle detectors. These imaging BNP sensors detect the binding of single nanoparticles on a flat surface functionalized with a specific capture molecule or an array of multiplexed capture probes. The functionalization step confers all molecular specificity for the sensor’s target but can introduce an unforeseen problem; a rough and inhomogeneous surface coating can be a source of noise, as these sensors detect small local changes in optical refractive index. In this paper, we review several optical technologies for label-free BNP detectors with a focus on imaging systems. We compare the surface-imaging methods including dark-field, surface plasmon resonance imaging and interference reflectance imaging. We discuss the importance of ensuring consistently uniform and smooth surface coatings of capture molecules for these types of biosensors and finally summarize several methods that have been developed towards addressing this challenge.

Protein microarrays are emerging tools which have become very powerful in multiplexed detection technologies. A variety of proteins can be immobilized on a sensor chip allowing for multiplexed diagnostics. Therefore, various types of analyte in a small volume of sample can be detected simultaneously. Protein immobilization is a crucial step for creating a robust and sensitive protein microarray-based detection system. In order to achieve a successful protein immobilization and preserve the activity of the proteins after immobilization, DNA-directed immobilization is a promising technique. Here, we present the design and the use of DNA-directed immobilized (DDI) antibodies in fabrication of robust protein microarrays. We focus on application of protein microarrays for capturing and detecting nanoparticles such as intact viruses. Experimental results on Single-particle interferometric reflectance imaging sensor (SP-IRIS) are used to validate the advantages of the DDI method.

Cells use three main ways of generating energy currency to drive metabolism: (i) conversion of adenosine diphosphate (ADP) to adenosine triphosphate (ATP) by the proton motive force through the rotor-stator ATP synthase; (ii) the synthesis of inorganic phosphate∼phosphate bonds via proton (or sodium) pyrophosphate synthase; or (iii) substrate-level phosphorylation through the direct donation from an active phosphoryl donor. A mechanism to produce a pyrophosphate bond as “energy currency” in prebiotic systems is one of the most important considerations for origin of life research. Baltscheffsky (1996) suggests that inorganic pyrophosphate (P_2O_7^(4-); PP_i) may have preceded ATP/ADP as an energy storage molecule in earliest life, produced by an H^+ pyrophosphatase. Here we test the hypothesis that PP_i could be synthesized in inorganic precipitates simulating hydrothermal chimney structures transected by thermal and/or ionic gradients. Appreciable yields of PP_i were obtained via substrate phosphorylation by acetyl phosphate within the iron sulfide/silicate precipitates at temperatures expected for an alkaline hydrothermal system.

A new type of amperometric cholesterol biosensor was fabricated to improve the biosensor characteristics such as sensitivity and reliability. For this purpose, a novel immobilization matrix 2-(4-fluorophenyl)-4,7-di(thiophene-2-yl)-1 H -benzo[ d ]imidazole (BIPF) was electrochemically deposited on a graphite electrode and used as a matrix for the immobilization of cholesterol oxidase (ChOx). Due to strong π–π stacking of aromatic groups in the structures of polymer backbone and enzyme molecule, one can easily achieve a sensitive and reliable biosensor without using any membrane or covalent bond formation between the enzyme molecules and polymer surface. Moreover, through pendant fluorine group of the polymer, H-bond formation between with enzyme molecules and polymer was generated. Cholesterol was used as the substrate and amperometric response was measured in correlation with cholesterol amount, at −0.7 V vs. Ag/AgCl in phosphate buffer (pH 7.0). Consequently, optimum conditions for this constructed biosensor were determined. K M app, I max , LOD and sensitivity values were investigated and calculated as 4.0 nM, 2.27 µA, 0.404 µM and 1.47 mA/mM cm 2 , respectively. A novel and accurate cholesterol biosensor was developed for the determination of total cholesterol in food samples.

Combination of nanoparticles and biomolecules attracted considerable attention in biosensing applications. In this study, effective surface design was investigated by modifying the electrode surface with pristine and functionalized gold nanoparticles. For this purpose, spherical gold nanoparticles were synthesized and characterized with UV–vis spectroscopy and transmission electron microscopy (TEM) analyses. Then, gold nanoparticles were modified with mercaptopropionic acid (MPA) yielding Au–S bonds (Au NPs/MPA). Moreover, a novel functional monomer, 6-(4,7-bis(2,3-dihydrothieno [3,4- b ][1,4]dioxin-5-yl)-2 H -benzo[ d ][1,2,3]triazol-2-yl)hexan-1-amine (BEDOA-6), was synthesized and used as an immobilization matrix for glucose biosensor. After successful electrochemical deposition of the polymer; poly(BEDOA-6) on graphite electrodes, immobilization of glucose oxidase (GOx) was carried out covalently with the help of crosslinking agent. During immobilization, Au NPs and Au NPs/MPA were used in biosensor fabrication in order to achieve the most effective surface design for target biosensor. In addition, SEM and fluorescence analyses were utilized to characterize the surface properties. The biosensor shows a wide linear range between 0.025 mM and 1.25 mM glucose concentration with a low detection limit of 0.025 mM. Also, kinetic parameters, operational and storage stabilities were determined. Finally, the biosensor was tested on beverages for glucose detection.

Triboelectric power harvesting and biochemical sensing inside poly(vinylidene fluoride) hollow fibers. Fiber‐based microfluidic energy harvesting system, which is also utilized as self‐powered chemical and biosensor. In vitro device concept demonstrating that triboelectric effect can be used for cell detection.

Hydrothermal chimneys and compartments comprising transition metal sulphides and associated minerals have been proposed as likely locations for the beginnings of life. In laboratory simulations of off-axis alkaline springs, it is shown that the interaction of a simulated alkaline sulphide-bearing submarine vent solution with a primeval anoxic iron-bearing ocean leads to the formation of chimney structures reminiscent of chemical gardens. These chimneys display periodicity in their deposition and exhibit diverse morphologies and mineralogies, affording the possibilities of catalysis and molecular sequestration. The addition of peptides and RNA to the alkaline solution modifies the elemental stoichiometry of the chimneys—perhaps indicating the very initial stage of the organic takeover on the way to living cells by charged organic polymers potentially synthesized in this same environment.

Objective: Apoptosis and its regulatory mechanisms take part in renal ischemia–reperfusion (I/R) injury which can result in acute renal failure and the inhibition of the caspase is considered as a new therapeutic strategy. In this context, we investigated the antiapoptotic and cytoprotective effects of iloprost, a prostacyclin analog, in kidney as a distant organ. Methods: Wistar albino rats were randomized into five groups (n = 12 in each) as sham, ischemia, I/R, iloprost (10 µ gk g −1 ), and I/R + iloprost (10 µ gk g −1 ). A 4 h reperfusion procedure was carried out after 4 h of ischemia. Caspase-8 was evaluated for death receptor-induced pathways, whereas caspase-9 was evaluated for mitochondriadependent pathways and caspase-3 was investigated for overall apoptosis. Superoxide dismutase (SOD) enzyme activity and nitrite content as an indicator of nitric oxide (NO) production were also analyzed in kidney tissues. Results: Caspases-3, -8, and -9 were all significantly elevated in both ischemia and I/R groups compared to the sham group; however, treatment with iloprost reduced caspases-3, -8, and -9. SOD enzyme activity was attenuated by iloprost when compared to ischemic rats. The different effects of NO were found which change according to the present situation in ischemia, I/R, and treatment with iloprost. Conclusions: These findings suggested that iloprost prevents apoptosis in both receptor-induced and mitochondria-dependent pathways in renal I/R injury and it may be considered as a cytoprotective agent for apoptosis. Understanding the efficiency of iloprost on the pathways for cell death may lead to an opportunity in the therapeutic approach for renal I/R injury.

Chemical gardens form when ferrous chloride hydrate seed crystals are added or concentrated solutions are injected into solutions of sodium silicate and potassium phosphate. Various precipitation morphologies are observed depending on silicate and phosphate concentrations, including hollow plumes, bulbs, and tubes. The growth of precipitates is controlled by the internal osmotic pressure, fluid buoyancy, and membrane strength. Additionally, rapid bubble-led growth is observed when silicate concentrations are high. ESEM/EDX analysis confirms compositional gradients within the membranes, and voltage measurements across the membranes during growth show a final potential of around 150-200 mV, indicating that electrochemical gradients are maintained across the membranes as growth proceeds. The characterization of chemical gardens formed with iron, silicate, and phosphate, three important components of an early earth prebiotic hydrothermal system, can help us understand the properties of analogous structures that likely formed at submarine alkaline hydrothermal vents in the Hadean-structures offering themselves as the hatchery of life.

We report on the use of a small light-weight mass spectrometer (MS) for chemical analysis of organic material directly from solution or from the solid state with potential value in future planetary missions. The mass spectrometer used in the experiments reported here is handheld and controlled from a laptop computer through custom software. Detection and identification of small organic molecules, including some that might be prebiotics, was achieved using methods relevant to in situ and remote sensing applications. The miniature MS was equipped with a discontinuous atmospheric pressure interface (DAPI) and a home-built electrosonic spray ionization (ESSI) source. Aqueous solutions of molecules of interest were examined using the ESSI technique, while desorption electrospray ionization (DESI) was applied to examine solid samples. The system performance was characterized by direct analysis of analytes belonging to several compound classes including biotic and abiotic amino acids, purines, pyrimidines, nucleosides and peptides. Detection limits in the sub-ppm range for solutions were achieved with the atmospheric pressure sampling/ionization interface. Tandem mass spectrometry (MS 2 ) was successfully applied to confirm trace detection of target compounds in mixtures. Multiple stage (MS n ) analysis, where n = 3–5, was employed for molecular structure confirmation and to demonstrate the high chemical specificity as well as the sensitivity of the instrumentation. The use of improved versions of this type of mass spectrometer on exploration missions could provide detailed chemical information on organic materials in physical states currently difficult to access. The high sensitivity and specificity, combined with rapid detection and the absence of requirements for sample preparation are encouraging features of the instrumentation.

We report photochemical studies of thin cryogenic ice films composed of N 2 , CH 4 and CO in ratios analogous to those on the surfaces of Neptune’s largest satellite, Triton, and on Pluto. Experiments were performed using a hydrogen discharge lamp, which provides an intense source of ultraviolet light to simulate the sunlight-induced photochemistry on these icy bodies. Characterization via infrared spectroscopy showed that C 2 H 6 and C 2 H 2 , and HCO are formed by the dissociation of CH 4 into H, CH 2 and CH 3 and the subsequent reaction of these radicals within the ice. Other radical species, such as C 2 , C 2 - , CN, and CNN, are observed in the visible and ultraviolet regions of the spectrum. These species imply a rich chemistry based on formation of radicals from methane and their subsequent reaction with the N 2 matrix. We discuss the implications of the formation of these radicals for the chemical evolution of Triton and Pluto. Ultimately, this work suggests that C 2 - , CN, HCO, and CNN may be found in significant quantities on the surfaces of Triton and Pluto and that new observations of these objects in the appropriate wavelength regions are warranted.

Field induced droplet ionization mass spectrometry (FIDI-MS) comprises a soft ionization method to sample ions from the surface of microliter droplets. A pulsed electric field stretches neutral droplets until they develop dual Taylor cones, emitting streams of positively and negatively charged submicrometer droplets in opposite directions, with the desired polarity being directed into a mass spectrometer for analysis. This methodology is employed to study the heterogeneous ozonolysis of 1-palmitoyl-2-oleoyl-sn-phosphatidylglycerol (POPG) at the air−liquid interface in negative ion mode using FIDI mass spectrometry. Our results demonstrate unique characteristics of the heterogeneous reactions at the air−liquid interface. We observe the hydroxyhydroperoxide and the secondary ozonide as major products of POPG ozonolysis in the FIDI-MS spectra. These products are metastable and difficult to observe in the bulk phase, using standard electrospray ionization (ESI) for mass spectrometric analysis. We also present studies of the heterogeneous ozonolysis of a mixture of saturated and unsaturated phospholipids at the air−liquid interface. A mixture of the saturated phospholipid 1,2-dipalmitoyl-sn-phosphatidylglycerol (DPPG) and unsaturated POPG is investigated in negative ion mode using FIDI-MS while a mixture of 1,2-dipalmitoyl-sn-phosphatidylcholine (DPPC) and 1-stearoyl-2-oleoyl-sn-phosphatidylcholine (SOPC) surfactant is studied in positive ion mode. In both cases FIDI-MS shows the saturated and unsaturated pulmonary surfactants form a mixed interfacial layer. Only the unsaturated phospholipid reacts with ozone, forming products that are more hydrophilic than the saturated phospholipid. With extensive ozonolysis only the saturated phospholipid remains at the droplet surface. Combining these experimental observations with the results of computational analysis provides an improved understanding of the interfacial structure and chemistry of a surfactant layer system when subject to oxidative stress.

Rare earth elements and selected trace elements were measured in 48 samples of carbonate and chert from stromatolites and associated facies in the 3.45 billion year old Strelley Pool Formation, Pilbara Craton, Western Australia. The samples show coherent REE+Y patterns that vary systematically with sedimentary facies. Chert samples from bedded cherts beneath the Strelley Pool Formation and from the upper bedded chert members in the formation show REE+Y patterns consistent with originating by precipitation from hydrothermal and mixed marine-hydrothermal fluids. In contrast, carbonates and cherts from the stromatolitic reef member share the essential shale-normalized characteristics of other Archean marine precipitates (LREE depletion, positive La and Gd anomalies, absence of a negative Ce anomaly and a strongly superchondritic Y/Ho ratio). The close correspondence between REE+Y signatures and independent sedimentary facies interpretations is viewed as strong evidence for the primary nature of REE+Y patterns. They can thus be used as a proxy for the fluids from which sediments precipitated. Mixing hyperbolae can be constructed that reproduce the chemistry of cherts and carbonates by mixing of hydrothermal and marine fluid endmembers throughout the entire vertical succession from beneath the Strelley Pool Formation to the uppermost cherts. The mixing hyperbolae provide semi-quantitative confirmation that the trace element compositions across the suite of cherts represent different mixtures of ambient seawater and hydrothermal fluids. Our results indicate that the Earth's oldest supracrustal carbonates and associated cherts record important aspects of the REE geochemistry of the waters in which they precipitated, and provide valuable information on possible habitats of some of Earth's earliest biota.

Germanium endometallo fullerene was syn- thesized by arcing Ge-impregnated graphite rod as anode and pure graphite rod as cathode. Photoluminescence (PL) and resistance measurements suggest that there are effec- tive interactions at the interface of Ge endometallo fullerene and poly 3-hexyl thiophene (P3HT). Four-fold enhancement of conductance has been found by adding just one weight percentage of Ge endometallo fullerene in the P3HT matrix at room temperature. However, at lower and higher tem- peratures, the enhancement in conductivity is low com- pared with room temperature, indicating the efficient charge transfer across the interface at the temperature range of 300-350 K. Atomic force microscopy (AFM) images also confirm the fact that temperature makes the more ordered heterojunctions between P3HT and Ge endohedral metallo- fullerene, which, in turn, trigger charge separation across interfaces. A sharp quenching in PL intensity of P3HT at room temperature by adding Ge endometallo fullerene indicates a strong interaction between the two and this composite material can be useful in photovoltaic cell. V C 2009

Previous work has concluded that H-D exchange occurs readily in polycyclic aromatic hydrocarbons frozen in deuterated water (D2O) irradiated with ultraviolet light. Here, we examine H-D exchange in methane-water ices following exposure to ultraviolet radiation and analyze the products formed as a result. We find that H-D exchange also occurs in methane-water ices by means of ultraviolet photolysis. Exchange proceeds through a radical mechanism that implies that almost all organic species will undergo significant H-D exchange with the matrix in water ices exposed to ultraviolet radiation. Given sufficient energetic processing of the ice, the H/D ratio of an ice matrix may be transferred to the organic species in the ice.

A method has been described for encapsulating Ge in a fullerene cage using GeO 2 and a graphite composite rod as anode and graphite as cathode. Annealing in an inert atmosphere before arcing, and the amount of GeO 2 in the rod determined the yield of Ge doped metallofullerene. Solvent extraction using soxlet in inert atmosphere followed by calcination in air was used to isolate metallofullerene from the soot. The insertion of Ge inside the fullerene was proven by ultra violet–visible absorption spectroscopy, matrix assisted laser desorption ionization-time of flight mass spectroscopy, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy.

We report a study on the broadband ultraviolet photolysis of methane–water ice mixtures, at low methane concentrations and temperatures relevant to the icy satellites of the outer Solar System. The photochemistry of these mixtures is dominated by the action of hydroxyl radicals on methane and the resulting products. This implies that, given sufficient exposure time, the methane will eventually be completely oxidized to carbon dioxide. The presence of methane inhibits the formation of hydrogen peroxide by serving as a trap for hydroxyl radicals. The distribution of photochemical products is broadly similar to that previously conducted using ion and electron sources, with some differences possibly attributable to the difference in radiation source. The results are applicable to a variety of icy bodies in the Solar System. On Enceladus, where methane mixed with water is measured in the plumes, methane in the surface ices is subject to oxidation and will eventually be converted to CO 2 . The C H stretch feature detected in the VIMS spectra of the Enceladus surface ice suggests that methane is currently being supplied to the surface ice, likely from re-condensation of the plume gas.

In the present study, monodisperse Fe 3 O 4 nanoparticles with diameters ranging from 10 nm to 25 nm were synthesized using a simple organic-phase synthetic route and these monodispersed nanoparticles were then used as catalyst for seed growth of carbon nanotube. Fe 3 O 4 nanoparticles were reduced to iron nanoparticles assembly by Argon mixed with 5% Hydrogen gas at 400 °C and then it was examined by atomic force microscopy (AFM), thermomechanical analysis (TMA) and powder diffraction X-ray spectroscopic techniques. XRD indicates that iron clusters are bcc in nature and AFM image shows that the iron nanoparticles assemblies are 50–65 nm in size. To control the agglomeration of iron nanoparticles, nanoporous hybrid support material of Al 2 O 3 and SiO 2 was used. However, this matrix also fails to stop the agglomeration of iron nanoparticles mainly due to the inhomogeneous distribution of pore diameters. TMA analysis of iron clusters shows a temperature-dependent morphology, therefore, the CNTs growth temperature critically ascertain the nature and structure of CNTs.

The dissociation of a wide range of oxygen-containing molecules following impact with electrons of carefully controlled energy is critically reviewed. Molecules considered range from diatomics, like O_2 and CO, to large molecules of biological and technological interest. Dissociation mechanisms are discussed and, where possible, quantitative data for the various possible processes, ionization, attachment, dissociation, excitation, emission etc., are presented. Gaps and discrepancies in our current data base are highlighted. Both graphical and tabular data are presented.

For in situ astrobiological studies of Mars or other planets, we must employ strategies that will enable us to verify whether our approach and prototype instruments are actually capable of distinguishing life from non-life. This must be done against a background of rigorously conducted scientific characterization of the environment or sample types being considered for measurement by the instruments under development. In this study we show how a combination of mineralogical and textural features can be considered a biosignature in an early Mars analogue environment, Death Valley, California. We propose that it is a combination of features in context of the geologic matrix which allows determination of biogenicity to be made. Polymineralic microbialites (organosedimentary formations constructed by microorganisms) from a spring pool at Badwater, within Death Valley National Park, are composed of alternating biogenic and abiogenic minerals in a distinct triplet sequence related to wet and dry seasons. A microbial community, occurring as a black biofilm, produced paired layers of two different mineral types: manganese oxyhydroxides and calcite. These biogenic layers are separated from the next pair by a gypsum layer and appear to be laid down in the wet season, with the gypsum (a mineral positively identified on Mars) precipitating in the dry part of the year, abiogenically (i.e., not dependent on microbial metabolic activity for its deposition). In addition, textural features (smaller grain size and less geometric morphology) unique to the biogenic vs the abiogenic layers, were consistently observed so that texture served as a biosignature in this environment.