Dinitrogen fixation and residue nitrogen of different managed legumes and nitrogen uptake of subsequent winter wheat [N2-Fixierung und residualer Stickstoff verschiedener Futterleguminosen sowie N-Aufnahme der Folgefrucht Winterweizen.]

Fixed nitrogen accumulated by legumes is the main nitrogen source for organic farming systems. Knowledge about the amount of fixed nitrogen, its pathways into forage yield, crop residues, soil-N and yield formation of the following crop is needed for designing crop rotations. Two field experiments were conducted in Northern Germany with differently managed (cut, mulched) legumes (red clover, alfalfa, white clover) in pure stands and various mixtures with two companion grasses (Lolium multiflorum, Lolium perenne) have been grown to determine N2-fixation, residue nitrogen and N-uptake of subsequent crops. Cropped grass/legume reached higher N2-fixation than mulched. While green manure grass/legume left up to 280 kg ha-1 of N in mulch, stubble and roots on the field, most cropped grass/legume mixtures left less than 110 kg N ha-1 in crop residues. Pure legume swards or legume rich mixtures showed higher N2-fixation than grass rich mixtures. N-uptake in late autumn and at maturity of the subsequent wheat was strongly correlated to the legume content in DM-yield

Yield, forage quality, residue nitrogen and nitrogen fixation of different forage legumes

Fixed nitrogen accumulated by legumes is the main nitrogen source for organic farming systems. Knowledge about the amount of fixed nitrogen, its pathways into forage yield, crop residues, soil-N and yield formation of the following crop is needed for designing crop rotations. In a field experiment conducted in Northern Germany differently managed (cut, mulched) legumes (red clover, alfalfa, white clover) in pure stands and in mixture with a companion grass (Lolium perenne) have been grown to determine Yield, forage-quality, N2-fixation and residue nitrogen. Cropped grass/legume reached higher N2-fixation than mulched. While green manure grass/legume left up to 296 kg ha-1 of N in mulch, stubble and roots on the field, most cropped grass/legume mixtures left less than 120 kg N ha-1 in crop residues. Cropped swards showed higher N2-fixation than the mulched mixtures. Swards with red clover or alfalfa reached higher legume contents and harvestable biomass than swards with white clover. Conclusions The results show that biomass production, forage yields, residue nitrogen and N fixation of grass/legume mixtures can be influenced by various combinations of legume species and management. The factors listed have to be considered carefully when planning crop rotations

Joining of thirty three percent by weight random glass fibre reinforced polystyrene using variable frequency microwave

[Abstract]: This paper extends the range of applications for Variable Frequency Microwave (VFM) (2 – 18 GHz) facilities to joining thirty three percent by weight glass fibre reinforced polystyrene composite [PS/GF (33%)]. With a given power level, the composite was exposed to various exposure times to microwave irradiation. The primer or coupling agent used was 5-minute two-part adhesive containing 100% liquid epoxy and 8% amine, i.e. Araldite, which was more readily microwave reactive than the composite itself. Bond strengths of the joints were lap shear tested and results were compared with those obtained using fixed frequency (2.45 GHz) microwave processing. The VFMF was operated under software control, which provided automatic data logging facilities. The maximum lap shear bond strength of joint was 430 N/cm2 using variable frequency microwave facility while that obtained by fixed frequency microwave configuration was only 331 N/cm2. The former is nearly 30% stronger than the latter

Simulation and optimization of n-type PERL silicon solar cell structure

Optimization of structure and process parameters of PERL (Passivated Emitter Rear Locally Diffused) silicon solar cell using SILVACO software package has been carried out. PERL single junction silicon solar cells are reported by researchers to have high efficiency (~ 20-25 %) and are promising for further improvement. Optimization is based on process and device simulation in SILVACO software package and integrating a Response Surface Methodology for optimal solution. Optimization of texture dimensions and ARC is followed by process parameters optimization for the emitter and base for best performance solar cell. A solar cell of efficiency 24 % is demonstrated by the simulation. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2794

A Survey Of The Forms Of Tuberculosis Encountered At Harare Hospital, Rhodesia, 1967—1969

A CAJM article on the forms of Tuberculosis encountered at Harare Central Hospital.It was decided to study the frequency with which tuberculosis was diagnosed in Africans admitted to the Harare Central Hospital in Salisbury, Rhodesia. We also wanted to learn how often this diagnosis was proven at the time of discharge of the patient, since we had reason to believe that tuberculosis was not an easy condition to prove in every case

The Impact of Medicare's Prospective Payment System on Psychiatric Patients Treated in Scatterbeds

Medicare's Prospective Payment System (PPS) for hospitals was phased-in during the 1884 Federal Fiscal Year. While many providers of psychiatric inpatient care were exempted from PPS patients treated in general hospital beds outside of psychiatric units (scatterbeds) were not. This allows for an initial assessment of the impact of PPS on psychiatric patients. We use a single equation model of hospital length of stay to estimate the impact of PPS. We allow for the possibility of both anticipating behavior and slow adjustment to the new payment scheme. The results indicate a substantial response to PPS over the first year of implementation. The estimated response includes sizable anticipatory and slow adjustment components. The findings suggest that policy discussions may be weighted too heavily in the direction of concern over hospital financial status given the ability of hospitals to change their behavior.

Evaluating the Economic and Environmental Sustainability of Integrated Farming Systems

Economic and environmental sustainability has become a major concern for forage-based animal production in Europe, North America and other parts of the world. Development of more sustainable farming systems requires an assimilation of experimental and modelling research. Field research is critical for supporting the development and evaluation of models, and modelling is needed to integrate farm components for predicting the long-term effects and interactions resulting from farm management changes. Experimentally supported simulation provides a tool for evaluating and comparing farming strategies and predicting their effect on the watershed, region and beyond

Age-related differences in corticospinal excitability during observation and motor imagery of balance tasks

Postural control declines across adult lifespan. Non-physical balance training has been suggested as an alternative to improve postural control in frail/immobilized elderly people. Previous studies showed that this kind of training can improve balance control in young and older adults. However, it is unclear whether the brain of young and older adults is activated differently during mental simulations of balance tasks. For this purpose, soleus (SOL) and tibialis motor evoked potentials (MEPs) and SOL H- reflexes were elicited while 15 elderly (mean ± SD = 71 ± 4.6 years) and 15 young participants (mean ± SD = 27 ± 4.6 years) mentally simulated static and dynamic balance tasks using motor imagery (MI), action observation (AO) or the combination of AO and MI (AO + MI). Young subjects displayed significant modulations of MEPs that depended on the kind of mental simulation and the postural task. Elderly adults also revealed differences between tasks, but not between mental simulation conditions. Furthermore, the elderly displayed larger MEP facilitation during mental simulation (AGE-GROUP; F(1,28) = 5.9; p = 0.02) in the SOL muscle compared to the young and a task-dependent modulation of the tibialis background electromyography (bEMG) activity. H-reflex amplitudes and bEMG in the SOL showed neither task- nor age- dependent modulation. As neither mental simulation nor balance tasks modulated H- reflexes and bEMG in the SOL muscle, despite large variations in the MEP-amplitudes, there seems to be an age-related change in the internal cortical representation of balance tasks. Moreover, the modulation of the tibialis bEMG in the elderly suggests that aging partially affects the ability to inhibit motor output

Towards quantitative prediction of proteasomal digestion patterns of proteins

We discuss the problem of proteasomal degradation of proteins. Though proteasomes are important for all aspects of the cellular metabolism, some details of the physical mechanism of the process remain unknown. We introduce a stochastic model of the proteasomal degradation of proteins, which accounts for the protein translocation and the topology of the positioning of cleavage centers of a proteasome from first principles. For this model we develop the mathematical description based on a master-equation and techniques for reconstruction of the cleavage specificity inherent to proteins and the proteasomal translocation rates, which are a property of the proteasome specie, from mass spectroscopy data on digestion patterns. With these properties determined, one can quantitatively predict digestion patterns for new experimental set-ups. Additionally we design an experimental set-up for a synthetic polypeptide with a periodic sequence of amino acids, which enables especially reliable determination of translocation rates.Comment: 14 pages, 4 figures, submitted to J. Stat. Mech. (Special issue for proceedings of 5th Intl. Conf. on Unsolved Problems on Noise and Fluctuations in Physics, Biology & High Technology, Lyon (France), June 2-6, 2008