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To monitor infection by the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) and successful vaccination against coronavirus disease 2019 (COVID‐19), the kinetics of neutralizing or blocking anti‐SARS‐CoV‐2 antibody titers need to be assessed. Here, we report the development of a quick and inexpensive surrogate SARS‐CoV‐2 blocking assay (SUBA) using immobilized recombinant human angiotensin‐converting enzyme 2 (hACE2) and human cells expressing the native form of surface SARS‐CoV‐2 spike protein. Spike protein‐expressing cells bound to hACE2 in the absence or presence of blocking antibodies were quantified by measuring the optical density of cell‐associated crystal violet in a spectrophotometer. The advantages are that SUBA is a fast and inexpensive assay, which does not require biosafety level 2‐ or 3‐approved laboratories. Most importantly, SUBA detects blocking antibodies against the native trimeric cell‐bound SARS‐CoV‐2 spike protein and can be rapidly adjusted to quickly pre‐screen already approved therapeutic antibodies or sera from vaccinated individuals for their ACE2 blocking activities against any emerging SARS‐CoV‐2 variants., A simple, inexpensive surrogate SARS‐CoV‐2 neutralization assay is introduced. Ectopic expression of the SARS‐CoV‐2 spike protein confers binding of Ramos‐Ig ‐ or HEK293 cells to plate‐bound recombinant human angiotensin‐converting‐enzyme‐2. This interaction can be blocked with reconvalescent or immune serum or with anti‐receptor‐binding domain antibodies. Bound spike‐expressing cells are quantitated with crystal violet.

Morphological findings in cases of intoxication are relatively rare in forensic pathology. In this article we report on a 26-year-old man who drank clear fluid from a tequila bottle that was given to him by a friend. Afterwards, the clear fluid was assumed to be smoke fluid containing diethylene glycol (DEG). The man died eight days later. Macroscopic and microscopic examination of the kidneys and the liver at forensic autopsy revealed findings typical of a DEG intoxication. In addition, the clinical course showed the typical triphasic pattern of symptoms. Toxicological analysis confirmed the presence of DEG in both the original smoke fluid and the tequila bottle. In conclusion, death was due to fatal intoxication by DEG. While most DEG intoxications have been mass poisoning incidents attributed to pharmaceutical products, the present case describes an unusual example of a single decedent.

Receptor occupancy, the ratio between amount of drug bound and amount of total receptor on single cells, is a biomarker for treatment response to therapeutic monoclonal antibodies. Receptor occupancy is traditionally measured by flow cytometry. However, spectral overlap in flow cytometry limits the number of markers that can be measured simultaneously. This restricts receptor occupancy assays to the analysis of major cell types, although rare cell populations are of potential therapeutic relevance. We therefore developed a receptor occupancy assay suitable for mass cytometry. Measuring more markers than currently available in flow cytometry allows simultaneous receptor occupancy assessment and high‐parameter immune phenotyping in whole blood, which should yield new insights into disease activity and therapeutic effects. However, varying sensitivity across the mass cytometer detection range may lead to misinterpretation of the receptor occupancy when drug and receptor are detected in different channels. In this report, we describe a method for optimization of mass cytometry receptor occupancy measurements by using antibody‐binding quantum simply cellular (QSC) beads for standardization across channels with different sensitivities. We evaluated the method in a mass cytometry‐based receptor occupancy assay for natalizumab, a therapeutic antibody used in multiple sclerosis treatment that binds to α4‐integrin, which is expressed on leukocyte cell surfaces. Peripheral blood leukocytes from a treated patient were stained with a panel containing metal‐conjugated antibodies for detection of natalizumab and α4‐integrin. QSC beads with known antibody binding capacity were stained with the same metal‐conjugated antibodies and were used to standardize the signal intensity in the leukocyte sample before calculating receptor occupancy. We found that QSC bead standardization across channels corrected for sensitivity differences for detection of drug and receptor and generated more accurate results than observed without standardization. © 2019 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.

The function of mitochondrial respiration during B cell fate decisions and differentiation remains equivocal. This study reveals that selection for mitochondrial fitness occurs during B cell activation and is essential for subsequent plasma cell differentiation. By expressing a mutated mitochondrial helicase in transitional B cells, we depleted mitochondrial DNA during B cell maturation, resulting in reduced oxidative phosphorylation. Although no changes in follicular B cell development were evident, germinal centers, class switch recombination to IgG, plasma cell generation and humoral immunity were diminished. Defective oxidative phosphorylation led to aberrant flux of the tricarboxylic acid cycle and lowered the amount of saturated phosphatidic acid. Consequently, MTOR activity and BLIMP-1 induction were curtailed whereas HIF1α, glycolysis and AMPK activity were amplified. Exogenous phosphatidic acid increased mTOR activity in activated B cells. Hence, mitochondrial function is required and selected for in activated B cells for the successful generation of functional plasma cells.

The global spread of SARS-CoV-2/COVID-19 is devastating health systems and economies worldwide. Recombinant or vaccine-induced neutralizing antibodies are used to combat the COVID-19 pandemic. However, the recently emerged SARS-CoV-2 variants B.1.1.7 (UK), B.1.351 (South Africa), and P.1 (Brazil) harbor mutations in the viral spike (S) protein that may alter virus-host cell interactions and confer resistance to inhibitors and antibodies. Here, using pseudoparticles, we show that entry of all variants into human cells is susceptible to blockade by the entry inhibitors soluble ACE2, Camostat, EK-1, and EK-1-C4. In contrast, entry of the B.1.351 and P.1 variant was partially (Casirivimab) or fully (Bamlanivimab) resistant to antibodies used for COVID-19 treatment. Moreover, entry of these variants was less efficiently inhibited by plasma from convalescent COVID-19 patients and sera from BNT162b2-vaccinated individuals. These results suggest that SARS-CoV-2 may escape neutralizing antibody responses, which has important implications for efforts to contain the pandemic., Graphical abstract, Comparison of the SARS-CoV-2 variants B.1.1.7, B.1.351, and P.1 shows that inhibitors under clinical evaluation are still effective in blocking entry, though the B.1.351 and P.1 variants evade antibody responses induced upon infection as well as vaccination and evade certain therapeutic antibodies.

Summary Plasma cells secreting affinity-matured antibodies develop in germinal centers (GCs), where B cells migrate persistently and directionally over defined periods of time. How modes of GC B cell migration influence plasma cell development remained unclear. Through genetic deletion of the F-actin bundling protein Swiprosin-1/EF-hand domain family member 2 (EFhd2) and by two-photon microscopy, we show that EFhd2 restrains B cell speed in GCs and hapten-specific plasma cell output. Modeling the GC reaction reveals that increasing GC B cell speed promotes plasma cell generation. Lack of EFhd2 also reduces contacts of GC B cells with follicular dendritic cells in vivo. Computational modeling uncovers that both GC output and antibody affinity depend quantitatively on contacts of GC B cells with follicular dendritic cells when B cells migrate more persistently. Collectively, our data explain how GC B cells integrate speed and persistence of cell migration with B cell receptor affinity.

Plasma cells depend on quality control of newly synthesized antibodies in the endoplasmic reticulum (ER) via macroautophagy/autophagy and proteasomal degradation. The cytosolic adaptor protein TFG (Trk-fused gene) regulates ER-Golgi transport, the secretory pathway and proteasome activity in non-immune cells. We show here that TFG is upregulated during lipopolysaccharide- and CpG-induced differentiation of B1 and B2 B cells into plasmablasts, with the highest expression of TFG in mature plasma cells. CRISPR-CAS9-mediated gene disruption of tfg in the B lymphoma cell line CH12 revealed increased apoptosis, which was reverted by BCL2 but even more by ectopic TFG expression. Loss of TFG disrupted ER structure, leading to an expanded ER and increased expression of ER stress genes. When compared to wild-type CH12 cells, tfg KO CH12 cells were more sensitive toward ER stress induced by tunicamycin, monensin and proteasome inhibition or by expression of an ER-bound immunoglobulin (Ig) μ heavy (µH) chain. CH12 tfg KO B cells displayed more total LC3, lower LC3-II turnover and increased numbers and size of autophagosomes. Tandem-fluorescent-LC3 revealed less accumulation of GFP-LC3 in starved and chloroquine-treated CH12 tfg KO B cells. The GFP:RFP ratio of tandem-fluorescent-LC3 was higher in tunicamycin-treated CH12 tfg KO B cells, suggesting less autophagy flux during induced ER stress. Based on these data, we suggest that TFG controls autophagy flux in CH12 B cells and propose that TFG is a survival factor that alleviates ER stress through the support of autophagy flux in activated B cells and mature plasma cells.Abbreviations: Ab, antibody; Ag, antigen; ASC, antibody-secreting cells; ATG, autophagy-related; BCR, B cell receptor; COPII, coat protein complex II; CpG, non-methylated CpG oligonucleotide; ER, endoplasmic reticulum; ERAD, ER-associated degradation; FO, follicular; GFP, green fluorescent protein; HC, heavy chain; Ig, immunoglobulin; IRES, internal ribosomal entry site; LC, light chain; MZ, marginal zone; NFKB, nuclear factor of kappa light polypeptide gene enhancer in B cells; TLR, toll-like receptor; UPR, unfolded protein response.

The sensing of microbial genetic material by leukocytes often elicits beneficial pro-inflammatory cytokines, but dysregulated responses can cause severe pathogenesis. Genome-wide association studies have linked the gene encoding phospholipase D3 (PLD3) to Alzheimer's disease and have linked PLD4 to rheumatoid arthritis and systemic sclerosis. PLD3 and PLD4 are endolysosomal proteins whose functions are obscure. Here, PLD4-deficient mice were found to have an inflammatory disease, marked by elevated levels of interferon-γ (IFN-γ) and splenomegaly. These phenotypes were traced to altered responsiveness of PLD4-deficient dendritic cells to ligands of the single-stranded DNA sensor TLR9. Macrophages from PLD3-deficient mice also had exaggerated TLR9 responses. Although PLD4 and PLD3 were presumed to be phospholipases, we found that they are 5' exonucleases, probably identical to spleen phosphodiesterase, that break down TLR9 ligands. Mice deficient in both PLD3 and PLD4 developed lethal liver inflammation in early life, which indicates that both enzymes are needed to regulate inflammatory cytokine responses via the degradation of nucleic acids.

Mass cytometry is increasingly employed in larger immune profiling studies involving data acquisitions across several days and multiple sites. For gaining a maximum of information from respective data by computational analyses, several techniques have been developed to minimize noise in mass cytometric data sets, such as sample banking, standardized instrument setup, sample barcoding, and signal normalization. However, the repeated preparation of cocktails composed of isotope-tagged antibodies remained a significant source of error. We here show that premixed antibody cocktails fail to deliver expected staining patterns when stored at 4°C for 4 weeks. As a solution, we developed and tested a cryopreservation method for highly multiplexed antibody cocktails for mass cytometry including lanthanide, palladium, and platinum conjugates that yielded stable staining patterns for at least 9 months when stored at temperatures below -80°C. Using frozen aliquots of antibody cocktails is an economic and flexible approach to significantly improve data consistency in large mass cytometry studies with repetitive staining/measurement cycles spanning several days or involving multiple data acquisition sites. © 2019 International Society for Advancement of Cytometry.

Polystyrene beads are broadly applied in flow cytometry. Implementing bead-based assays in mass cytometry is desired but hampered by the lack of an elemental label required for their detection. In this study, we introduce stable osmium tetroxide labeling as a universal approach for generating functionalized beads readily detectable by mass cytometry. We demonstrate the utility of osmium-labeled beads for signal spillover compensation in mass cytometry, and, strikingly, their application in quantitative Ab-binding capacity assays combined with high-dimensional profiling of human PBMC enabled the systematic assessment of receptor expression profiles across large numbers of cellular phenotypes. This analysis confirmed increased monocytic Siglec-1 expression in active systemic lupus erythematosus patients and, additionally, revealed interrelated reductions of CD4 expression by regulatory and memory CD4 T cells and HLA-DR expression by myeloid dendritic cells, pointing toward defective cross-talk at the immunological synapse that may limit immune responses in systemic lupus erythematosus. By converting conventional flow cytometry beads into beads suitable for mass cytometry, our approach paves the way toward the broad implementation of bead-based assays in high-dimensional cell profiling studies by mass cytometry in biomedical research.

Introduction One-third of the Australian population lives outside major cities and this group has worse health outcomes. Telehealth is becoming an accepted way to improve patient access to specialist healthcare. Over 200,000 Australian’s have hepatitis C virus (HCV) and new treatments are very effective and well tolerated. We aim to demonstrate that HCV treatment utilising telehealth support for care delivery has cure rates similar to onsite care in clinical trials. We also report length of consultation and calculate reductions in travel and carbon output. Methods Patient demographic, clinical, and treatment outcome data were collected prospectively from hospital software and analysed retrospectively. This was an audit of all patients treated for HCV in one year from a single tertiary hospital that included telehealth in their care delivery. Results Sustained virological response was achieved in 51/52 (98%) patients with completed treatment courses, and 51/58 (88%) of those who had a planned telehealth consultation as part of their management. A median of 634 km of patient travel was saved per telehealth consultation. Discussion We found that a telehealth-supported outreach programme for patients in regional Australia with HCV produced similar outcomes to clinical trials. There was a considerable saving in time and cost for the patients and significant environmental benefit through the reduction in carbon footprint associated with travel to distant specialist health services. We conclude that telehealth facilitated outreach is a feasible and effective way to access HCV treatment and cure in regional Australia.

Herein, we report on the first enantioselective synthesis of the sparteine-type alkaloids virgidivarine (1) and virgiboidine (2). The stereoselective construction of the challenging dipiperidine core within 1 and 2 was realized by applying an intramolecular ene-ene-yne ring-rearrangement metathesis (RRM) protocol. In combination with this sequence, an unprecedented tandem metathesis/oxidation reaction was established. Subsequent to the RRM event, the Ru-alkylidene species was converted into the highly potent dihydroxylation catalyst RuO4 by the addition of NaIO4. This transformation rendered five sequential reactions that include an ene-ene-yne RRM/dihydroxylation/glycol cleavage in a one-pot procedure. This approach provides practical and general access to dipiperidines and piperidino-quinolizidines. Despite their wide use in organic and organometallic chemistry as well as their occurrence in biologically active natural products, methods are still lacking for the stereoselective synthesis of these motifs.

A new structural type has been found for the compound with nominal composition (MgxCa1−x)Ni2.6. Its structure is made of nine layers (6 AB2 + 3 AB5) stacked in an original manner. The average structure may be regarded as a Gd2Co7 type-structure in which half of the AB5 blocks have been replaced by AB2 blocks. The hydrogen sorption properties are similar to those of the Ca0.4Mg0.6Ni3 compound with the PuNi3 structure. However, the resulting arrangement departs significantly from the PuNi3 structural type since a symmetry reduction from R-3m into R3 takes place.

To get deeper insight into the phase relations in the end-member system Fe2SiO4 and in the system (Fe, Mg)2SiO4 experiments were performed in a multi-anvil apparatus at 7 and 13 GPa and 1,000–1,200°C as a function of oxygen fugacity. The oxygen fugacity was varied using the solid oxygen buffer systems Fe/FeO, quartz–fayalite–magnetite, MtW and Ni/NiO. The run products were characterized by electron microprobe, Raman- and FTIR-spectroscopy, X-ray powder diffraction and transmission electron microscopy. At fO2 corresponding to Ni/NiO Fe-ringwoodite transforms to ferrosilite and spinelloid according to the reaction: 9 Fe2SiO4 + O2 = 6 FeSiO3 + 5 Fe2.40Si0.60O4. Refinement of site occupancies in combination with stoichiometric Fe3+ calculations show that 32% of the total Fe is incorporated as Fe3+ according to $$ \left ( {{\text{Fe}}_{1.60}^{2 + } {\text{Fe}}_{0.40}^{3 + } } \right)^{\text{VI}} \left ( {{\text{Si}}_{0.60} {\text{Fe}}_{0.40}^{3 + } } \right)^{\text{IV}} {\text{O}}_{4} . $$ From the Rietveld refinement we identified spl as spinelloid III (isostructural with wadsleyite) and/or spinelloid V. As we used water in excess in the experiments the run products were also analyzed for structural water incorporation. Adding Mg to the system increases the stability field of ringwoodite to higher oxygen fugacity and the spinel structure seems to accept higher Fe3+ but also water concentrations that may be linked. At oxygen fugacity corresponding to MtW conditions similar phase relations in respect to the breakdown reaction in the Fe-end-member system were observed but with a strong fractionation of Fe into spl and Mg into coexisting cpx. Thus, through this strong fractionation it is possible to stabilize very Fe-rich wadsleyite with considerable Fe3+ concentrations even at an intermediate Fe–Mg bulk composition: assuming constant K D independent on composition and a bulk composition of x Fe = 0.44 this fractionation would stabilize spl with x Fe = 0.72. Thus, spl could be a potential Fe3+ bearing phase at P–T conditions of the transition zone but because of the oxidizing conditions and the Fe-rich bulk composition needed one would expect it more in subduction zone environments than in the transition zone in senso stricto.

In the departments of nuclear medicine, patients are treated with relatively large activities of (131)I for therapeutic purposes. The applied activities are in the range of 200-10 000 MBq. Consequently, individuals situated in the dwellings of the patients dismissed from the hospital are subjected to an external as well as an internal radioiodine exposition. Internal exposition is due to the inhalation of (131)I exhaled by the patients. In this article, the measurements of radioactivity exhaled by patients with various thyroid diseases, treated with (131)I in the department of Nuclear Medicine of the Radiological Centre in Goettingen and in the Hospital of Nuclear Medicine in Wuerzburg are presented. The measurements of activities exhaled by patients were repeated daily, up to 25 d after the treatment. In addition, the residual activities were monitored by measuring the external dose rates, and by measuring the (131)I activity in the urine of these patients. In some cases, the exhaled radioiodine was separated into three fractions: the elemental, the organically bound and the aerosol-bound iodine fraction. On the basis of the proposed measurements, the doses received by the family members of a discharged patient treated with (131)I were estimated by a model calculation.

Agarose gel electrophoresis, which separates and sizes linear DNA and RNA fragments, is arguably the most basic and essential technique in molecular biology. It is commonly employed for analysis of PCR products, plasmid DNA, and products of restriction enzyme digestion. It is the first step for analysis of specific DNA and RNA fragments by northern and Southern blots. In this unit, we provide both written instructions and photographic images to take the reader from preparing a first agarose gel to analyzing results and determining the size of sample DNA. We include two protocols: agarose gel electrophoresis (commonly used to analyze DNA) and denaturing gel electrophoresis (for analyzing RNA). We have divided each protocol into four basic steps: (1) preparing and pouring the agarose gel; (2) preparing and loading samples; (3) running the agarose gel; and (4) staining the gel using the fluorescent stain ethidium bromide to visualize DNA and RNA. © 2015 by John Wiley & Sons, Inc. Keywords: DNA; RNA; separation; sizing; ethidium bromide; voltage; TAE; TBE; bromphenol blue; xylene cyanol; northern blotting; Southern blotting

We describe structural properties and biological activities of two related O-glycosylated peptide toxins isolated from injected (milked) venom of Conus striatus, a piscivorous snail that captures prey by injecting a venom that induces a violent, spastic paralysis. One 30 amino acid toxin is identified as kappaA-SIVA (termed s4a here), and another 37 amino acid toxin, s4b, corresponds to a putative peptide encoded by a previously reported cDNA. We confirm the amino acid sequences and carry out structural analyses of both mature toxins using multiple mass spectrometric techniques. These include electrospray ionization ion-trap mass spectrometry and nanoelectrospray techniques for small volume samples, as well as matrix-assisted laser desorption/ionization time of flight mass spectrometric analysis as a complementary method to assist in the determination of posttranslational modifications, including O-linked glycosylation. Physiological experiments indicate that both s4a and s4b induce intense repetitive firing of the frog neuromuscular junction, leading to a tetanic contracture in muscle fiber. These effects apparently involve modification of voltage-gated sodium channels in motor axons. Notably, application of either s4a or s4b alone mimics the biological effects of the whole injected venom on fish prey.

Corn inbreds are often more sensitive to herbicides than hybrids. Field experiments were conducted with three corn inbreds to (1) evaluate inbred sensitivity to the acetamide herbicides acetochlor, dimethenamid, flufenacet, and metolachlor, (2) compare the effects of various crop safeners in combination with acetochlor and metolachlor, and (3) measure the effect of herbicide microencapsulation on acetochlor injury. Herbicides were applied preemergence at the registered rate and at two, three, or four times the registered rate in corn. Injury ratings, plant population, and the percentage of plants showing acetamide injury symptoms were used to measure herbicide effect. The inbreds ‘Mo17’ and ‘Great Lakes 15’ (GL15) were sensitive to acetamide injury. Reductions in plant population and increases in the injury rating and the percentage of injured plants were caused by acetochlor, dimethenamid, flufenacet, metolachlor, and flufenacet + metribuzin when applied at three times the registered rate. The inbred ‘B73’ was not injured. The safeners benoxacor and dichlormid reduced injury caused by metolachlor. The percentage of plants injured by metolachlor 15 days after treatment (DAT) was lower when benoxacor was the safener compared to dichlormid. By 28 DAT, plants treated with safeners recovered from injury, and there were no differences between the treatments. The safeners dichlormid and furilazole reduced, but did not always eliminate, injury caused by acetochlor applied at three times the registered rate. Microencapsulation of acetochlor reduced injury to GL15. When the safeners dichlormid or furilazole were included in an acetochlor formulation, microencapsulation did not further reduce corn injury.

The impacts of new CT requirements for ozone disinfection of Cryptosporidium are evaluated using a desktop CT disinfection analysis. The analysis is applied to the design of new and upgraded ozone systems for two water treatment plants in Virginia. The results indicate that the feasibility of ozone disinfection of Cryptosporidium is dependent on ozone demand and decay characteristics of the water supply and may not be feasible for water supplies with moderate to high ozone decay rates. The CT analysis is a useful design procedure to evaluate the benefit-cost tradeoffs of using ozone to achieve alternative disinfection goals.

In the failing heart, the local angiotensin II concentration is increased, and the extent of cardiac angiotensin II release is related to the clinical signs of heart failure. The enzymes involved in myocardial generation of angiotensin II are the angiotensin-converting enzyme (ACE) and chymases. While myocardial angiotensin II is mainly generated by chymases in the human heart, ACE inhibitors nevertheless improve left ventricular (LV) function, attenuate LV remodelling and reduce mortality in heart failure patients. These beneficial actions of ACE inhibitors, however, relate to their beneficial effect on kinin metabolism. Angiotensin II type 1 receptor (AT1) antagonists also mediate part of their beneficial effects through increased bradykinin formation. However, in contrast to ACE inhibitors, AT1 receptor antagonists attenuate downstream signalling of angiotensin II-induced AT1 receptor activation, which increases the activity of existing proteins (e.g. NADPH oxidase) and the de novo synthesis of proteins (e.g. inducible nitric oxide synthase, tumor necrosis factor-α ) in cardiomyocytes. Given the multiple actions of AT1 receptor activation on cardiomyocyte and non-cardiomyocyte function in the presence of an increased myocardial AngII concentration, the reduction of cardiovascular mortality and rate of hospitalization following AT1 receptor blockade in heart failure patients not receiving ACE inhibitors is not surprising. Most importantly, the beneficial effects of AT1 receptor blockade are not only achieved when used as an alternative to ACE inhibition, but also when used on top of ACE inhibitors.

Purpose: The NMR-MOUSE® is an open and mobile sensor for measuring NMR relaxation parameters in organic matters. T1-measurements of the subcutaneous fatty tissue and the skin are reported. Material and Method: For the first time, the NMR-MOUSE® was employed to measure the signal recovery following saturation of the skin and the subcutaneous fatty tissue of three patients, before and after administering a contrast agent. Results: Despite a low signal-to-noise ratio, changes in the relaxation behaviour of the skin could be detected. Malignant tissue exhibits faster signal recovery than scar tissue and healthy tissue, which only show a small difference. Conclusions: Changes in the relaxation behavior can be monitored with the NMR-MOUSE®. Before the clinical use of the NMR-MOUSE, sensitivity, sensor mounting device, and sensor tuning must be improved. Further investigations need to be performed on a statistically relevant number of patients.

The corrosion behavior of milled Mg prepared by high-energy ball milling for 10 h has been investigated in alkaline solutions by electrochemical impedance spectroscopy and compared with that of unmilled Mg. X-ray powder diffraction indicates a crystallite size of 34 nm for the milled Mg compared to >100 nm for the unmilled powder. Chemical analyses show no significant iron contamination in milled Mg powder, indicating the absence of tools erosion during the milling procedure. In contrast, significant MgO enrichment in the milled powder is observed (6.5 wt.% after 10 h milling compared to 1.0 wt.% before milling). The oxygen contamination is mainly attributed to the powder oxidation occurring during milling. From XPS analyses, no MgO enrichment is detected on milled Mg electrode surface, confirming that MgO is dispersed homogeneously in the bulk of the material rather than to segregate on its surface. Electrochemical impedance spectroscopy demonstrates clearly the better corrosion resistance of milled Mg compared to unmilled Mg in passive conditions (KOH solution, pH=14) and in more active corrosion conditions (borate solution, pH=8.4). This is illustrated by a nobler corrosion potential and by a significant increase of the interfacial resistance related to the film and charge-transfer reaction. Moreover, the variation of the different electrochemical parameters (corrosion potential, interfacial resistance and capacitance) with immersion time is less accentuated and tends more rapidly to a steady state with milled Mg, suggesting an enhancement of the Mg(OH)2 formation kinetic. The origin of the distinctive passivation behavior of ball-milled Mg is discussed.

BepiColombo is the planetary mission of the Cosmic Vision Programme of the European Space Agency (ESA), devoted to the thorough exploration of Mercury and its environment. It will be carried out as a joint project between ESA and JAXA (Japanese Aerospace Exploration Agency). BepiColombo consists of two spacecraft, the Mercury Planetary Orbiter (MPO) and the Mercury Magnetospheric Orbiter (MMO). The MMO studies the wave and particle environment of the planet, while the MPO is dedicated to the characterization of Mercury itself. Both spacecraft will be in dedicated orbits that have been optimized for their tasks. They will be launched together on a single Soyuz-Fregat in July 2012 and reach Mercury about 4 years later. Then BepiColombo will start its one year mission, which will provide the detailed information necessary to understand the process of planetary formation and evolution in the hottest part of the proto-planetary nebula as well as the similarities and differences between the magnetospheres of Mercury and the Earth.

Ultraviolet (UV) disinfection is being considered for inactivation of pathogens in filtered surface waters across North America. MS2 coliphage is the most commonly used test microbe for UV reactor validation in North America, and the development of UV dose-response data for MS2 at bench scale is an integral part of validation testing. This research evaluated the effect of water quality (e.g., turbidity, particle count, particle size, and absorbance) and sample depth on inactivation of MS2 coliphage in 17 filtered waters. In addition, the inactivation performance of low-pressure (LP) and medium-pressure (MP) lamp types was compared. Results indicated that turbidity, particle count, and absorbance, when factored into the bench-scale dose measurement, did not affect UV inactivation of MS2 coliphage in filtered waters meeting federal regulations. UV light from MP lamps appeared more effective than LP UV for inactivating MS2. These results suggest that water quality should not be considered a major factor in properly designed UV bench-scale tests or in reactor validation challenges that use inactivation kinetics of MS2 coliphage as a dose-measurement tool in filtered surface waters.

Binary Ca–Ni and ternary Ca–Mg–Ni alloys have been synthesized by mechanical alloying. The phase structures and hydrogen storage properties of the as-milled nanocrystalline and the thermally annealed alloys have been investigated. The phase structure changes with the (Ca+Mg)/Ni and the Mg/Ca ratios in the Ca–Mg–Ni ternary system. A too high Mg/Ca ratio leads to the formation of a MgNi2 phase. The plateau pressure increases with Mg content in the CaxMg1−xNi2 and CaxMg1−xNi3 pseudo-binary alloys, however, the hydrogen storage capacity decreases. Mg does not substitute Ca in the CaNi5 and Ca2Ni7 compounds. Adding or substituting a small amount of Mg in these compounds destroys the A2B7 as well as the AB5 structures and results in an AB3 phase and an accompanying nickel phase.

The hydrolysis reaction of nanostructured MgH 2 and nanocomposites MgH 2 –X (X=Ca, Li, LiAlH 4 ) prepared by ball-milling was studied as a function of milling time and component proportion. It was found that nanocrystallinity greatly enhances the hydrolysis kinetics. Moreover, in this new class of chemical hydrides, the reaction also proceeds to full completion, contrary to some conventional chemical hydrides where the reaction stops before total completion due to the formation of passivation layers. The effect of addition of acidic solutions was also investigated.

Nanocrystalline Ti–Ru–Fe–O (2-1-1-2) was prepared by mechanical alloying in a ZOZ attritor. Vacuum plasma spray (VPS) was then used to deposit coatings of this material on a substrate. Energy dispersive X-ray fluorescence and X-ray diffraction analysis was used to follow the change in the chemical composition and crystalline structure of the powder upon deposition by VPS. Nanocrystalline Ti–Ru–Fe–O (2-1-1-2) prepared by the ZOZ attritor contains more than 50 wt.% of hexagonal Fe 2 Ti and a smaller amount ( 2 Ti and Ru results in the formation of several cubic phases with lattice parameters ranging from 2.96 to 3.02 A. This reflects a change in the Ru content on the 1 a ( 1 2 , 1 2 , 1 2 ) site of the cubic lattice. The deposition process also results in the formation of Ti 2 O 3 . This phase is present in excess at the surface of the coating but can be efficiently dissolved through etching in an acid solution. The cathodic overpotential for hydrogen evolution of such activated coatings in typical chlorate electrolysis conditions is η 250 =−550 mV.

Indoor VOC (volatile organic compound) exposure has been shown to be correlated with airway symptoms and allergic manifestations in children. An investigation was conducted within an ongoing birth cohort study (LISA: Lifestyle-Immune System-Allergy) of the association between maternal exposure to VOCs and immune status at birth, in particular the cytokine secretion profile of cord-blood T cells. In a randomly selected group of 85 neonates, cytokine-producing cord-blood T cells were analyzed using intracellular cytokine detection. VOC exposure was measured in children's dwellings by passive sampling, while parents were asked to complete questionnaires about possible sources of VOC exposure. Adjusted odds ratios (ORs) were calculated by logistic regression based on categorized quartiles. A positive association was found between elevated percentages of interleukin-4-producing (IL-4) type 2 T cells and exposure to naphthalene (OR = 2.9) and methylcyclopentane (OR = 3.3). Exposure to tetrachloroethylene was associated with reduced percentages of interferon-gamma-producing (IFN-gamma) type 1 T cells (OR = 2.9). In addition, smoking during pregnancy was correlated with a higher indoor air concentration of naphthalene (OR = 3.8), new carpets in infants' bedrooms with elevated methylcyclopentane concentrations (OR = 4.1), and home renovation with a higher trichloroethylene burden (OR = 4.9). Our data suggest that maternal exposure to VOC may have an influence on the immune status of the newborn child.

Tourniquet-imposed ischemia-reperfusion of extremities generates reactive oxygen and nitrogen species (RONS), which can disrupt intermediary metabolism and ATP production. This study tested the hypothesis that fluid resuscitation with pyruvate, a natural antioxidant and metabolic fuel, ameliorates the deleterious effects of ischemia-reperfusion on intermediary metabolism in skeletal muscle. Anesthetized male goats (∼25 kg) were bled to a mean arterial pressure of 48 ± 1 mmHg and then subjected to 90 min hindlimb ischemia with a tourniquet and femoral crossclamp, followed by 4-h reperfusion. Lactated Ringers (LR) or pyruvate Ringers (PR) was infused intravenous for 90 min, from 30 min ischemia to 30 min reperfusion, to deliver 0.05 mmol kg−1 min−1 lactate or pyruvate. Time controls (TC) underwent neither hemorrhage nor hindlimb ischemia. Lipid peroxidation product 8-isoprostane, RONS-sensitive aconitase and creatine kinase activities, antioxidant superoxide dismutase activity, and phosphocreatine phosphorylation potential ([PCr]/[{Cr}{Pi}]), an index of tissue energy state, were measured in reperfused gastrocnemius at 90 min resuscitation ( n = 6 all groups) and 3.5 h post-resuscitation ( n = 8 TC, 9 LR, 10 PR). PR more effectively than LR suppressed 8-isoprostane formation, prevented inactivation of aconitase and creatine kinase, doubled superoxide dismutase activity, and augmented [PCr]/([Cr][Pi]). Pyruvate-enriched Ringer’s is metabolically superior to Ringer’s lactate for fluid resuscitation of tourniqueted muscle.

Polarization-induced orientational order in three different azopolymers is investigated and discussed with respect to the formation of surface relief gratings induced by holographic exposure. For this purpose the birefringence and dichroism induced by different light polarization, namely linear, elliptical or circular, has been studied. To determine the symmetry and the induced amount of orientational order the illuminated region is characterized by the scalar Maier-Saupe order parameter S. Tensor gratings were induced in these materials by holographic exposure with different kinds of polarization patterns and were investigated with polarization- and atomic force microscopy. The gratings are characterized by diffraction efficiencies as well as by depth and shape of the surface modulation. Large surface modulations (>2.5μm) and diffraction efficiencies (>90%) for a 5μm thick film were obtained.

The mixing efficiency of four alternative ozone dissolution systems, including conventional bubble diffusion and pipeline injection/diffusion reactors, were compared by measuring the variability of ozone residual measurements at the outlet of each reactor. The standard deviation and coefficient of variation of a time series of residual measurements were used to provide a quantitative measure of the level of mixing in the reactor. The results indicate that properly designed pipeline dissolution systems provide significantly improved mixing over oxygen-fed or air-fed bubble diffusion systems. Minimum mixing criteria for bubble diffusion systems cited in the literature may underestimate the level of mixing required to achieve stable ozone residuals downstream of the dissolution chamber of conventional bubble diffusion chambers.

Cigarette smoking is associated with an increased risk of leukemia; benzene, an established leukemogen, is present in cigarette smoke. By combining epidemiologic data on the health effects of smoking with risk assessment techniques for low-dose extrapolation, we assessed the proportion of smoking-induced total leukemia and acute myeloid leukemia (AML) attributable to the benzene in cigarette smoke. We fit both linear and quadratic models to data from two benzene-exposed occupational cohorts to estimate the leukemogenic potency of benzene. Using multiple-decrement life tables, we calculated lifetime risks of total leukemia and AML deaths for never, light, and heavy smokers. We repeated these calculations, removing the effect of benzene in cigarettes based on the estimated potencies. From these life tables we determined smoking-attributable risks and benzene-attributable risks. The ratio of the latter to the former constitutes the proportion of smoking-induced cases attributable to benzene. Based on linear potency models, the benzene in cigarette smoke contributed from 8 to 48% of smoking-induced total leukemia deaths [95% upper confidence limit (UCL), 20-66%], and from 12 to 58% of smoking-induced AML deaths (95% UCL, 19-121%). The inclusion of a quadratic term yielded results that were comparable; however, potency models with only quadratic terms resulted in much lower attributable fractions--all < 1%. Thus, benzene is estimated to be responsible for approximately one-tenth to one-half of smoking-induced total leukemia mortality and up to three-fifths of smoking-related AML mortality. In contrast to theoretical arguments that linear models substantially overestimate low-dose risk, linear extrapolations from empirical data over a dose range of 10- to 100-fold resulted in plausible predictions.

The long-term effects of high bone resorption on blood ionized calcium and calciotropic hormone levels following oophorectomy in 6-month-old Sprague-Dawley female rats were investigated. Fasting urine and blood samples were collected from 16 sham and 16 oophorectomized (oophx) rats preoperatively and up to 130 days postoperatively. From 50 days postoperation, daily injections of 17-β estradiol (E2) (20 μg/kg body weight) were administered subcutaneously to eight of the oophx rats. Urine hydroxyproline excretion (OHPrE) and serum osteocalcin were significantly elevated (P < 0.001) as a result of oophorectomy and normalized within 6 days of E2 replacement. Urine deoxypyridinoline and total serum alkaline phosphatase were significantly elevated (P < 0.001) following oophorectomy and suppressed to control levels after 37 days of E2 replacement. Blood ionized calcium was significantly reduced in oophx rats (P < 0.001) compared with sham rats and was normalized by E2 replacement at 55 days posttreatment. Serum 1,25 dihydroxyvitamin D (1,25(OHD)2D3) was significantly elevated (P < 0.001) in oophx rats and again was normalized by E2 at 55 days posttreatment. Serum parathyroid hormone (PTH) was unaffected by oophorectomy. These data indicate that despite increased bone resorption following oophorectomy, blood ionized calcium levels are decreased. The increased bone turnover in oophx rats was rapidly suppressed by E2 replacement before ionized calcium levels were normalized, suggesting a direct effect of estrogen on the modulation of bone cell activity. The depression of blood ionized calcium levels following oophorectomy, which is not mediated by calciotropic hormones, suggests an effect of estrogen on intestinal calcium absorption, renal handling of calcium, or a combination of both.

The enantioselective total synthesis of the dipyrrolidine alkaloid (-)- TRANS-dendrochrysine was accomplished in 18 steps starting from tropone. The key step was a ring-rearrangement -metathesis for the construction of the bisheterocyclic skeleton of the natural product in a single step.

During moderate prolonged myocardial ischemia, the myocardium is dysfuctional but can remain viable. In such ischemic and dysfunctional myocardium, contractile function is reduced in proportion to the reduction in regional myocardial blood flow, i.e., a state of "perfusion-contraction matching" exists. The metabolic status of such myocardium improves over the first few hours, as myocardial lactate production is attenuated and creatine phosphate, after an initial reduction, returns to control values. Ischemic myocardium, characterized by perfusion-contraction matching, metabolic recovery and lack of necrosis, has been termed "short-term hibernating myocardium". "Short-term hibernating" myocardium can respond to an inotropic stimulation with increased contractile function, however, at the expense of a renewed worsening of the metabolic status. A role for endogenous adenosine in the development of hibernation has been excluded, since neither contractile function, metabolic parameters, nor viability are altered by increased catabolism of endogenous adenosine by infusion of adenosine deaminase. Also activation of ATP-dependent potassium channels is not responsible for "short-term hibernation". "Short-term hibernating" myocardium has, however, reduced calcium responsiveness.

High energy ball-milling of Pt, Ru, and Al in a 1:1:8 atomic ratio has been used to produce CO tolerant unsupported Pt-Ru based catalysts for the oxidation of hydrogen in polymer electrolyte fuel cells. After leaching Al, this catalyst [Pt 0.5 -Ru 0.5 (Al 4 )] displays a specific area of 38 m 2 /g. It shows hydrogen oxidation performance and CO tolerance equivalent to those of Pt 0.5 -Ru 0.5 Black from Johnson Matthey, the commercial catalyst which was found to be the most CO tolerant one in this study. Pt 0.5 -Ru 0.5 (Al 4 ) is a composite catalyst. It consists of two components: (i) small crystallites (∼ 4 nm) of a Pt-Al solid solution (1-3 Al wt%) of low Ru content, and (ii) larger Ru crystallites. The providers of oxygenated species necessary for the electrochemical oxidation of CO on Pt are either oxidized Al or Ru. The latter may be either on the surface of the Pt-Al (+Ru) alloy crystallites or at the surface of the larger Ru crystallites. Pt 0.5 -Ru 0.5 (Al 4 ) provides a stable current under H 2 + 100 ppm CO.

The highly explosive bismuth triazide, Bi(N3)3, was obtained in pure form by the reaction of BiF3 with Me3SiN3 in acetonitrile under solvothermal conditions at temperatures between 90 and 100 °C. X-ray, (14)N NMR, infrared, and Raman spectra are discussed along with the data for the acetonitrile, acetone, and dmso adducts. The influence of the solvent on the purity of the azide products is studied in detail for Bi(N3)3 and the [Bi(N3)6](3-) ion. Moreover, temperature dependent structural dynamics in the [Bi(N3)6](3-) ion, which is caused by small changes in the local environment around the [Bi(N3)6](3-) ion in the solid state, was studied by temperature variable single crystal X-ray and Raman studies. The azido-chlorido ligand back exchange was studied in detail by NMR techniques in [Bi(N3)6](3-) and Bi(N3)3 when chlorinated solvents such as CH2Cl2 were utilized leading to the formation of CH2(N3)Cl and/or HN3 along with partially chlorinated bismuth azides.

A novel class of photochemically active amphiphiles has been synthesized containing a ketone moiety as a biradical or radical pair precursor on the hydrophobic tail of sodium sulfate surfactants. Alteration of the molecular structure of each ketone-containing surfactant allows for the systematic and predictable manipulation of the micellar size and shape, both of which are important in determining the coupling between the unpaired electrons confined within the micelle and the intraradical dynamics. The structure of the resulting aggregates has been analyzed by small-angle neutron scattering (SANS). The results show that the amphiphiles form ellipsoidal micelles with aggregation numbers between 30 and 150 that depend on the balance between monomer dimensions and steric effects caused by the atomic spatial arrangement within the hydrophobic tail of the different surfactants.

Cocoamidopropyl betaines are becoming increasingly important because of their mild and effective surface-active properties, especially in cosmetic formulations. Their analysis, especially the determination of their concentration in commercially available solutions, is very complicated. This paper describes different techniques - titrations, chromatography and NMR-spectroscopy - that can be effectively used to characterize betaine solutions. By using these methods, detailed information on the chemical structure of the betaine molecules and of the by-products in the solution can be obtained. Additionally they can be used to quantify the betaine concentration very precisely. The combination of these techniques gives information on the fatty acid distribution of the betaines, allows differentiation between surface-active and surface-inactive betaines and helps to characterize non-betainic structures in the solutions. For quality control purposes the titration with perchloric acid gives the best results.

X-band time-resolved electron paramagnetic resonance (TREPR) spectra of 1,16- and 1,21- acylalkyl biradicals, obtained in toluene solution at low temperatures (187−253 K), are reported. The spectra show a strong temperature dependence in their patterns of chemically induced electron spin polarization. The spin-correlated radical pair (SCRP) mechanism dominates at high temperatures, while the radical pair mechanism (RPM) is the main pattern at lower temperatures. It is postulated that the SCRP spectrum is suppressed at the lower temperature due to molecular motion on a time scale which modulates the exchange interaction (J) between the unpaired electrons. Simultaneously the RPM is enhanced by this motion. Average values of J calculated from end-to-end distance distributions for the C21 biradical show that in the absence of this dynamic effect, an intense SCRP spectrum would be present at the lower temperature. The results demonstrate that the interpretation of average J couplings may be difficult in temperature regions where these motional effects dominate the appearance of the spectrum.

〈100〉 and 〈111〉-Ge single crystals were preamorphized in a thin surface layer using 50 keV or 85 keV N+ ions. Ion beam induced epitaxial crystallization (IBIEC) and interfacial amorphization (IBIIA) at the amorphous/crystalline interface were studied using different kinds of high energy ion beams. The crystallization rate for the 〈100〉-Ge is about 1.5 times higher than that for 〈111〉-Ge. The total recrystallised thickness depends mainly on the nuclear energy deposition and the irradiation temperature. Interfacial amorphization is detected in Ge for the first time. Cross section TEM micrographs show a sharp amorphous/crystalline interface for both IBIEC and IBIIA. The fit of the experimental data yields an activation energy of 0.82 eV for IBIEC and 1.16 eV for IBIIA.

A new type of ozone contactor, called the SVI-DT (sidestream venturi injection with downflow tube) contactor, was evaluated at pilot scale and compared with the performance of a traditional countercurrent flow, fine-bubble diffusion contactor. The specially designed downflow tube, equipped with one or more pressurized sidestream venturi injectors and installed inside an ozone reactor, facilitated the dissolution of ozone into water. The results showed that the SVI-DT contactor achieved high mass transfer rates and outperformed the fine-bubble diffusion contactor in removing color and yielding higher and longer-lasting dissolved ozone residuals. The hydraulic behavior of the new contactor was also evaluated, and operating limits were established for maintaining stable two-phase flow conditions in the downflow tube.

Near-infrared emissions of the SL9 impact sites of Jupiter have been recorded on July 16-18, 1994, at ESO (La Silla, Chile). A very strong emission of methane was recorded between 3.50 and 3.56 μm, shortly after impact H, showing evidence for a temporary increase of the Jovian stratospheric temperature. Emissions of H 2 (2.12 μm) and H 3 + (3.53 μm) were also detected above some of the impact sites, several hours after the impacts. The observed H 3 + emissions, however, seem to be at least partly contaminated by the southern aurora. A strong continuum was also detected at 2.12 μm over most of the impact sites, presumably due to intense scattering of reflected sunlight by stratospheric haze.

The coexpression of the natriuretic peptides ANP, BNP and CNP as well as their differential regulation in mouse macrophages was demonstrated by quantitative PCR, HPLC analysis, and specific radioimmunoassays. Exposure of peritoneal- and bone marrow-derived macrophages to various immunomodulators revealed that bacterial LPS strikingly increases (up to 300-fold) the mRNA coding for CNP as does zymosan (up to 15-fold). In this respect, neither the phorbol ester PMA nor the glucocorticoid dexamethasone had any effect. Examination of macrophages for ANP mRNA showed a similar response to LPS and zymosan, though only a three- to sixfold increase, confirming previous data. In contrast, the concentration of mRNA coding for brain natriuretic peptide in these cells was reduced by dexamethasone (up to twofold) as well as LPS (two- to fivefold). No change was observed upon challenge with zymosan or PMA. The findings at the mRNA level are complemented by their corresponding peptide products. Incubation of macrophages with LPS resulted in a two- and fivefold elevation of intracellular ANP and CNP immunoreactivity, respectively. The amount of peptides released from cells under these conditions was found increased for ANP (threefold) and CNP (10-fold). No changes were observed for both intra- and extracellular brain natriuretic peptide. The coexpression of natriuretic peptides in macrophages as well as their different regulations by immunomodulators suggest discrete functions of these peptides within the immune system.

The influence of loading on the activity and stability of heat-treated carbon-supported cobalt phthalocyanine electrocatalysts for oxygen reduction was studied. The Co loading on the carbon support was varied from 0 to 8 weight percent (w/o), while heat-treatment temperatures ranging from 500 to 1100 C were studied. There is an optimum value of the Co loading on the carbon support (about 3.5 w/o) over which the catalytic activity of the Co on carbon catalyst decreases. This trend is observed in both half-cell (rotating disk electrode measurements) and H{sub 2}/O{sub 2} fuel cell measurements. The optimum value of the Co loading on the carbon support is independent of the heat-treatment temperature. An explanation is proposed for this observation. The authors have also performed short-term (1.5 to 18 h) life tests with the 3.5 w/o Co on carbon-support materials heat-treated at various temperatures. It is shown that the current density lost after 18 h of operation is a function of the heat-treatment temperature being lower the higher the temperature. The observed increase in the stability of the material with the heat-treatment temperature is best explained by considering the protective role played by the graphitic-like layer surrounding the Co metal particles.