Photosynthetic responses to irradiance by the photosymbionts of the two Red Sea sponges Theonella swinhoei (Gray) and Cliona vasti®ca (Hancock) growing under dim light conditions were measured in situ (in September 1997) using a newly developed underwater pulse amplitude modulated (PAM) ̄uorometer. Relative rates of photosynthetic electron transport (ETR) were calculated as the e€ective quantum...

Isolated maize bundle sheath chloroplasts showed substantial rates of noncyclic photophosphorylation. A typical rate of phosphorylation coupled to whole-chain electron transport (methylviologen or ferricyanide as acceptor) was 60 mumol per hour per milligram chlorophyll) with a coupling efficiency (P/e(2)) of 0.6. Partial electron transport reactions driven by photosystem I or II supported phos...

The rugose colonial variant of Vibrio cholerae O1 El Tor produces an exopolysaccharide (EPS(ETr)) that enables the organism to form a biofilm and to resist oxidative stress and the bactericidal action of chlorine. Transposon mutagenesis of the rugose variant led to the identification of vpsR, which codes for a homologue of the NtrC subclass of response regulators. Targeted disruption of vpsR in...

The non-coupled substrate oxidation mediated by components of the electron transport chain that are not coupled to energy accumulation (such as plant alternative oxidase and rotenone-insensitive NADH dehydrogenases) and uncoupled respiration are peculiar features of plant mitochondria. The physiological significance of such energy-wasting oxidation processes is still debated. It is proposed tha...

Plant factories using artificial light to produce vegetables have high energy costs due the demand for electricity lighting. Compared conventional sources, light-emitting diodes (LEDs) offer possibility of tailoring spectrum and regulating intensity are more energy-efficient in terms conversion regardless levels lighting intensity. Optimal daily integral (DLI) requirements key factors plant gro...

the transport properties of liquids and gases through polymeric materialsplay a very important role in some areas of industrial applications. in thisstudy, natural rubber (nr)/caco3 composites were prepared by melt mixingmethod. by equilibrium swelling test, the transport process of toluene in the prepared natural rubber composites was investigated. the diffusion and transport of toluene throug...

Organic mixed valence compounds consisting of bisdiarylamino charge-bearing units with an oligothiophene bridge and oligothiophene radical cations have been compared using molecular modeling. The study has been performed with oligomers of 1 to 22 thiophene units. These two series of molecules have several properties in common, and intramolecular Single Electron Transfer (SET) in both series can...

Establishing mechanisms and intrinsic reactivity in the oxidation of phenol with water as the proton acceptor is a fundamental task relevant to many reactions occurring in natural systems. Thanks to the easy measure of the reaction kinetics by the current and the setting of the driving force by the electrode potential, the electrochemical approach is particularly suited to this endeavor. Despit...

In this paper, the hemoglobin (Hb)-collagen microbelt modified electrode with three-dimensional configuration was fabricated via the electrospinning method. Direct electron transfer of the Hb immobilized into the electrospun collagen microbelts was greatly facilitated. The apparent heterogeneous electron transfer rate constant (k(s)) was calculated to be 270.6s⁻¹. The electrospun Hb-collagen mi...

The paper studies the kinetic equation for electron transport in semiconductors. New formulas for the heat generation rate are derived by analyzing the basic scattering mechanisms. In addition, properties of the steady state distribution are discussed and possible extensions of the deviational particle Monte Carlo method to the area of electron transport are proposed.