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Strategy of interference-free atomic hydrogen detection in flames using femtosecond multi-photon laser-induced fluorescence

Hydrogen atoms are key species in combustion of hydrogen/hydrocarbon fuels. Interference-free detection of hydrogen atoms natively generated in flames using femtosecond laser-induced fluorescence (LIF) was investigated employing two colors, i.e., 243 nm and 486 nm, as excitation source: two-photon excitation followed by a relay one-photon excitation. This strategy was compared with another commonl

Efficient evaluation of humoral immune responses by the use of serum pools

Background: Collection and testing of individual serum samples are often used in research to gain knowledge about e.g. the humoral response against bacteria or virus. This is a valid but time-consuming method and might be a waste of valuable serum samples for inefficient research. So far, no study has considered using serum pools as a quick and efficient screening method to confirm or deny hypothe

Solving large instances of the RSA problem in flexgrid elastic optical networks

We present an optimization procedure that mixes advanced large-scale optimization methods and heuristics to solve large instances (with over 1.7 million integer variables) of the routing and spectrum allocation (RSA) problem - a basic optimization problem in flexgrid elastic optical networks. We formulate the problem as a mixed-integer program for which we develop a branch-and-price algorithm enha

Bats may eat diurnal flies that rest on wind turbines

Bats are currently killed in large numbers at wind turbines worldwide, but the ultimate reason why this happens remains poorly understood. One hypothesis is that bats visit wind turbines to feed on insects exposed at the turbine towers. We used single molecule next generation DNA sequencing to identify stomach contents of 18 bats of four species (Pipistrellus pygmaeus, Nyctalus noctula, Eptesicus

Entrapment of air during imbibition of agglomerated powder beds

Complete wetting is crucial for efficient recombination of powders. On the powder bed scale, wetting is governed solely by capillary forces and the resistance to flow, i.e. spontaneous imbibition. Slow or incomplete imbibition of the powder bed may lead to gelling of the liquid front, which will stop the recombination process and cause the formation of lumps, which is usually undesirable. In this

Carbon dioxide narcosis : Influence of short-term high concentration carbon dioxide inhalation on EEG and cortical evoked responses in the rat

The effects of 1 min exposure to 80% CO2 inhalation was studied in rats under light general anaesthesia with N2O. It was found that 80% CO2 gave a rapid slowing of the EEG as well as a rapid decrease of the amplitude of cortical somatosensory evoked potentials. Only minor influences upon the blood pressure and heart rate were seen. The changes were found to be transient and most of the EEG effects

Microstructure, crystallographic texture and mechanical behaviour of friction stir processed Mg-Zn-Ca-Zr alloy ZKX50

The feasibility of applying friction stir processing (FSP) to locally homogenise and to refine the microstructure of a recently developed Mg-Zn-Ca(-Zr) alloy, ZKX50, has been examined. The application of a single pass of FSP resulted in dissolution of coarse intermetallic particles at dendrite boundaries and grain refinement, from an average grain size of ~60 µm in the as-cast state to ~1.2 µm. Th

Strategies to design clinical studies to identify predictive biomarkers in cancer research

The discovery of reliable biomarkers to predict efficacy and toxicity of anticancer drugs remains one of the key challenges in cancer research. Despite its relevance, no efficient study designs to identify promising candidate biomarkers have been established. This has led to the proliferation of a myriad of exploratory studies using dissimilar strategies, most of which fail to identify any promisi

Development of Plasmodium falciparum specific naïve, atypical, memory and plasma B cells during infancy and in adults in an endemic area

Background: B-cells are essential in immunity against malaria, but which sub-sets of B-cells specifically recognize Plasmodium falciparum and when they appear is still largely unknown. Results: Using the flow cytometry technique for detection of P. falciparum specific (Pf+) B-cells, this study for the first time measured the development of Pf+ B cell (CD19+) phenotypes in Ugandan babies from birth

Metabolites controlling the rate of starch synthesis in the chloroplast of C3 plants

The extent to which different stromal metabolites affecting ADPglucose pyrophosphorylase control the rate of photosynthetic starch production in the chloroplast of C3 plants has been examined by kinetic model studies. The results indicate that ATP, glucose 1‐phosphate, 3‐phosphoglycerate, fructose 6‐phosphate, and orthophosphate may provide significant contributions to the starch synthesis rate ch

A mathematical model of the Calvin photosynthesis cycle

A mathematical model is presented for photosynthetic carbohydrate formation in C3 plants under conditions of light and carbon dioxide saturation. The model considers reactions of the Calvin cycle with triose phosphate export and starch production as main output processes, and treats concentrations of NADPH, NAD+, CO2, and H+ as fixed parameters of the system. Using equilibrium approximations for a

A rapid‐equilibrium model for the control of the Calvin photosynthesis cycle by cytosolic orthophosphate

A simple model based on rapid‐equilibrium assumptions is derived which relates the steady‐state activity of the Calvin cycle for photosynthetic carbohydrate formation in C3 plants to the kinetic properties of a single cycle enzyme (fructose bisphosphatase) and of the phosphate translocator which accounts for the export of photosynthate from the chloroplast. Depending on the kinetic interplay of th

Quantum chemical calculations of the reorganization energy of blue- copper proteins

The inner-sphere reorganization energy for several copper complexes related to the active site in blue-copper protein has been calculated with the density functional B3LYP method. The best model of the blue-copper proteins, Cu(Im)2(SCH3)(S(CH'3)2)(0/+), has a self-exchange inner-sphere reorganization energy of 62 kJ/mol, which is at least 120 kJ/mol lower than for Cu(H2O)(+/2+)/4 This lowering of

Childhood leukaemia survivors' experiences of long-term follow-ups in an endocrine clinic – A focus-group study

The survival rate after childhood cancer has improved markedly and today more than 80% of patients will survive. Many childhood cancer survivors suffer from late complications due to radiotherapy and chemotherapy. Survivors of Acute Lymphoblastic Leukaemia (ALL), treated with cranial radiotherapy, are at a particularly high risk of having endocrine complications. Purpose To illuminate childhood AL

IFCC approved HPLC reference measurement procedure for the alcohol consumption biomarker carbohydrate-deficient transferrin (CDT) : Its validation and use

Carbohydrate-deficient transferrin (CDT) is used as a biomarker of sustained high alcohol consumption. The currently available measurement procedures for CDT are based on various analytical techniques (HPLC, capillary electrophoresis, nephelometry), some differing in the definition of the analyte and using different reference intervals and cut-off values. The Working Group on Standardization of CD

Elevated ambulatory systolic-diastolic pressure regression index is genetically determined in hypertensive patients with coronary heart disease

Objectives: Ambulatory systolic-diastolic pressure regression index (ASDPRI) as a composite marker of cardiovascular (CV) properties is related to CV complications. However, genetic determinants of ASDPRI are not known. The aim of this study is to report the relationship between certain single nucleotide polymorphisms (SNP) and ASDPRI in hypertensive patients with CAD confirmed by coronary angiogr