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Performance, energy and cost evaluation of a nanofiltration plant operated at elevated temperatures

The influence of temperature on cost and energy consumption during nanofiltration has been evaluated. The effect of temperature on pressure drop, fouling, concentration polarisation and changes in the membrane performance were evaluated experimentally and theoretically. Nanofiltration experiments using pure solutions and wastewater from the meat industry were performed at 25 and 55 °C with an Alfa

The growing season greenhouse gas balance of a continental tundra site in the Indigirka lowlands, NE Siberia

Carbon dioxide and methane fluxes were measured at a tundra site near Chokurdakh, in the lowlands of the Indigirka river in north-east Siberia. This site is one of the few stations on Russian tundra and it is different from most other tundra flux stations in its continentality. A suite of methods was applied to determine the fluxes of NEE, GPP, R-eco and methane, including eddy covariance, chamber

Characterization of the conical intersection of the visual pigment rhodopsin at the CASPT2//CASSCF/AMBER level of theory

The branching plane associated with the conical intersection controlling the photochemical Z -> E isomerization reaction of rhodopsin has been mapped using a CASPT2//CASSCF/ AMBER quantum mechanics-molecular mechanics method. The nature of the derivative coupling and gradient difference vectors spanning the branching plane has been investigated, showing that the conical intersection is not only as

The microbial communities and primary productivity of cryoconite holes in an Arctic glacier (Svalbard 79°N)

The microbial communities and photosynthetic capacity of cryoconite holes on the Midre Lovénbreen Glacier at 79°N in Spitzbergen (Svalbard Archipelago) were investigated in July/August 2000 and July 2001. The constituents of the microbial assemblages were more abundant in material on the cryoconite bottoms than in the overlying water. Bacterial concentrations ranged from 1.00 to 4.502104 ml-1 in t

Histamine uptake by human endometrial cells expressing the organic cation transporter EMT and the vesicular monoamine transporter-2

Cellular reuptake of monoamines, which is mediated by cell membrane transporters, is followed by accumulation in vesicles by vesicular monoamine transporters (VMAT). The aim of this study was to demonstrate the presence of functional monoamine transporters with high affinity for histamine in human endometrial tissue, since histamine has been implicated as a paracrine signal during endometrial deci

Movement artefact suppression in blood perfusion measurements using a multifrequency technique

The standard way of suppressing movement artefacts in Doppler measurements is by means of a high-pass filter. This is because artefacts usually are of high amplitude, but have low frequencies. The immediate drawback is, then, that low-velocity blood flow is also filtered out. In this paper, a method to reduce movement artefacts in blood perfusion measurements is proposed, using simultaneous transm

Cyclodextrins in hydrophobically modified poly(ethylene glycol) solutions: Inhibition of polymer-polymer associations

in an aqueous solution of a hydrophobically, end-modified poly(ethylene glycol) polymer, HM-PEG, the thickening effect is dependent on intermolecular hydrophobic associations and the formation of a network structure. In the present investigation cyclodextrin, CD, has been added to an aqueous HM-PEG solution and a decrease in Newtonian viscosity has been followed. The decreased viscosity refers to

An African origin for the intimate association between humans and Helicobacter pylori

Infection of the stomach by Helicobacter pylori is ubiquitous among humans. However, although H. pylori strains from different geographic areas are associated with clear phylogeographic differentiation(1-4), the age of an association between these bacteria with humans remains highly controversial(5,6). Here we show, using sequences from a large data set of bacterial strains that, as in humans, gen

Origin of photocurrent in lateral quantum dots-in-a-well infrared photodetectors

Interband and intersubband transitions of lateral InAs/In0.15Ga0.85As dots-in-a-well quantum dot infrared photodetectors were studied in order to determine the origin of the photocurrent. The main intersubband transition contributing to the photocurrent (PC) was associated with the quantum dot ground state to the quantum well excited state transition. By a comparison between intersubband PC measur

Upregulation of Flt3 expression within the bone marrow Lin(-)Sca1(+)c-kit(+) stem cell compartment is accompanied by loss of self-renewal capacity

Flt3 has emerged as a potential regulator of hematopoietic stem cells (HSC). Sixty percent of cells in the mouse marrow Lin(-)Sca1(+)c-kit(+) HSC pool expressed flt3. Although single cell cloning showed comparable high proliferative, myeloid, B, and T cell potentials of Lin(-)Sca1(+)c-kit(+)flt3(+) and Lin(-)Sca1(+)c-kit(+)flt3(-) cells, only Lin(-)Sca1(+)c-kit(+)flt3(-) cells supported sustained

Particle-induced phase separation in mixed polymer solutions

The influence of added colloidal particles on the phase separation of mixed aqueous polymer solutions is investigated. Two types of particles (polystyrene latex or silica) and different combinations of segregating polymers (dextran of varying molar mass combined with poly(ethylene oxide) (PEO) of varying molar mass, or Ucon, a copolymer of ethylene oxide and propylene oxide) were used. All systems

In vitro effect of fibrinogen on Candida albicans germ tube formation

Pseudohyphae formation by Candida albicans blastoconidia, as seen in vaginal smears, is a phenotypical change commonly assumed to mean fungal invasiveness, i.e. not mere colonization. C. albicans forms germ tubes in vitro in the presence of serum. In our search for inhibitory components of germ tube formation, we decided to study fibrinogen. The inhibition of germ tube formation by clinical isolat

Entanglement at finite temperatures in the electronic two-particle interferometer

In this work we discuss a theory for entanglement generation, characterization and detection in fermionic two-particle interferometers (2PIs) at finite temperature. The motivation for our work is provided by the recent experiment by the Heiblum group (Neder et al 2007 Nature 448 333) realizing the two particle interferometer proposed by Samuelsson et al (2004 Phys. Rev. Lett. 92 026805). The exper

Novel polymer-polymer conjugates for recovery of lactic acid by aqueous two-phase extraction

A new family of polymer conjugates is proposed to overcome constraints in the applicability of aqueous two-phase systems for the recovery of lactic acid. Polyethylene glycol-polyethylenimine (PEI) conjugates and ethylene oxide propylene oxide-PEI (EOPO-PEI) conjugates were synthesized. Aqueous two-phase systems were generated when the conjugates were mixed with fractionated dextran or crude hydrol