516 research outputs found
Effects of Rumen Fill on Intake and Milk Production in Dairy Cows Fed Perennial Ryegrass
Physical limitation often limits dry matter intake (DMI) of high producing cows or cows fed high forage diets. The extent to which DMI is regulated by distention in the rumen depends upon the cow’s energy requirement and filling effects of the diet offered (Allen, 2000). The objective here was to challenge middle lactation dairy cows with rumen fill (rumen inert bulk – RIB) feeding ryegrass fresh cut (indoors) or grazed to determine whether RIB affects intake and milk production
High-resolution stimulated Raman spectroscopy and analysis of v2 and v3 bands of 13C2H4 using the D2h top data system
HRMS 2015, Dijon, France, August 24-28, 2015Peer Reviewe
Acquisition efficiency of Flavescence dorée phytoplasma by Scaphoideus titanus Ball from infected tolerant or susceptible grapevine cultivars or experimental host plants
The rate of Flavescence dorée phytoplasma (FDP) acquisition by the leafhopper vector Scaphoideus titanus Ball was tested under field and glass house conditions confining healthy reared nymphs on canes of FDP-infected grapevines or on FDP-infected cuttings collected in the field during the dormant season. Acquisition tests were performed using FD-tolerant (Merlot) or highly susceptible (Pinot blanc) grapevine cultivars, or alternatively using experimentally infected broadbean plants. Frequency of FDP acquisition by leafhoppers was evaluated using a polymerase chain reaction (PCR) assay. Different batches of insects were confined on the same infected source plants in the vineyard for acquisition access periods (AAP) of 7 d at a time at intervals of 15-20 d during spring and summer. When diseased Pinot blanc grapevines were used as source plants, acquisition by leafhoppers and transmission to healthy grapevines increased over summer, while almost no acquisition or transmission was observed when diseased Merlot grapevines were used as source plants. Tests conducted under controlled conditions confirmed that Merlot is a poorer source of FDP than Pinot blanc; the optimum FDP source for S. titanus was broadbean although this plant is not a natural host of the leafhopper. It is assumed that grapevine cultivars play an important role in influencing the proportion of FDP-infected leafhoppers in the vineyards and therefore influencing the rate of disease progress.
Does the Feeding Behaviour of Dairy Cows Differ When Fed Ryegrass Indoors vs. Grazing?
Dairy cows eating ryegrass ingest smaller boli when grazing than when fed indoors (93 vs. 142 g; Boudon et al., 2004). To investigate whether this difference in bolus affects feeding behaviour of the cows, an automated system (chewing halters) was used to monitor feeding behaviour of cows given ad libitum access to perennial ryegrass in individual feed troughs (indoor feeding, IF) or at pasture (grazing, GR)
Early transitions and tertiary enrolment: The cumulative impact of primary and secondary effects on entering university in Germany
Our aim is to assess how the number of working class students entering German universities can effectively be increased. Therefore, we estimate the proportion of students from the working class that would successfully enter university if certain policy interventions were in place to eliminate primary effects (performance differentials between social classes) and/or secondary effects (choice differentials net of performance) at different transition points. We extend previous research by analysing the sequence of transitions between elementary school enrolment and university enrolment and by accounting for the impact that manipulations at earlier transitions have on the performance distribution and size of the student ‘risk-set’ at subsequent transitions. To this end, we develop a novel simulation procedure which also seeks to find viable solutions to the shortcomings in the German data landscape. Our findings show that interventions are most effective if they take place early in the educational career. Neutralizing secondary effects at the transition to upper secondary school proves to be the single most effective means to increase participation rates in tertiary education among working class students. However, this comes at the expense of lower average performance levels. (DIPF/author
Mapping spectroscopic uncertainties into prospective methane retrieval errors from Sentine-5 and its precursor
Sentinel-5 (S5) and its precursor (S5P) are future European satellite missions aiming at global monitoring of methane (CH4) column average dry air mole fractions (XCH4). The spectrometers to be deployed on-board the satellites record spectra of sunlight backscattered from the Earth\u27s surface and atmosphere. In particular, they exploit CH4 absorption in the shortwave infrared spectral range around 1.65 µm (S5 only) and 2.35 µm (both, S5 and S5P) wavelength. Given an accuracy goal of better than 2% for XCH4 to be delivered on regional scales, assessment and reduction of potential sources of systematic error such as spectroscopic uncertainties is crucial. Here, we investigate how spectroscopic errors propagate into retrieval errors on the global scale. To this end, absorption spectra of a ground-based Fourier Transform Spectrometer (FTS) operating at very high spectral resolution serve as estimate for the quality of the spectroscopic parameters. Feeding the FTS fitting residuals as a perturbation into a global ensemble of simulated S5 and S5P-like spectra at relatively low spectral resolution, XCH4 retrieval errors exceed 1% in large parts of the world and show systematic correlations on regional scales, calling for improved spectroscopic parameters
The HITRAN2016 Molecular Spectroscopic Database
This paper describes the contents of the 2016 edition of the HITRAN molecular spectroscopic compilation. The new edition replaces the previous HITRAN edition of 2012 and its updates during the intervening years. The HITRAN molecular absorption compilation is composed of five major components: the traditional line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, infrared absorption cross-sections for molecules not yet amenable to representation in a line-by-line form, collision-induced absorption data, aerosol indices of refraction, and general tables such as partition sums that apply globally to the data. The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, added line-shape formalisms, and validity. Moreover, molecules, isotopologues, and perturbing gases have been added that address the issues of atmospheres beyond the Earth. Of considerable note, experimental IR cross-sections for almost 300 additional molecules important in different areas of atmospheric science have been added to the database. The compilation can be accessed through www.hitran.org. Most of the HITRAN data have now been cast into an underlying relational database structure that offers many advantages over the long-standing sequential text-based structure. The new structure empowers the user in many ways. It enables the incorporation of an extended set of fundamental parameters per transition, sophisticated line-shape formalisms, easy user-defined output formats, and very convenient searching, filtering, and plotting of data. A powerful application programming interface making use of structured query language (SQL) features for higher-level applications of HITRAN is also provided
The effects of social service contact on teenagers in England
Objective: This study investigated outcomes of social service contact during teenage years.
Method: Secondary analysis was conducted of the Longitudinal Survey of Young People in England (N = 15,770), using data on reported contact with social services resulting from teenagers’ behavior. Outcomes considered were educational achievement and aspiration, mental health, and locus of control. Inverse-probability-weighted regression adjustment was used to estimate the effect of social service contact.
Results: There was no significant difference between those who received social service contact and those who did not for mental health outcome or aspiration to apply to university. Those with contact had lower odds of achieving good exam results or of being confident in university acceptance if sought. Results for locus of control were mixed.
Conclusions: Attention is needed to the role of social services in supporting the education of young people in difficulty. Further research is needed on the outcomes of social services contact
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