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991.
992.
The purpose of this study was to investigate the potential of affecting milking frequency in an Automatic Milking System (AMS) by changing ingredient composition of the concentrate fed in the AMS. In six experiments, six experimental concentrates were tested against a Standard concentrate all supplied in the amounts of 5 kg/cow/day. Fifteen cows were fed the experimental concentrate and another 15 cows the Standard concentrate for 14 days and then for the next 14 days the cows were fed the opposite diets to be their own control. The change from one mixture to the next was done over only one day. In each experiment the 30 cows were composed of 12–14 of Danish Holstein, 8–10 of Danish Red and 8 were Jerseys. Basal mixed ration (MR) was fed ad libitum and intake was recorded individually. The effect of the different concentrates on intake and production was evaluated within experiment against the Standard concentrate. A marked effect was found on the number of visits of the cows in the AMS and the subsequent milk production in relation to composition of the concentrate. The composition of the concentrates also influenced the composition of the milk and the MR intake. Based on the overall responses the cows preferred a mixture containing Barley and Oats. Also Wheat based concentrate appeared to be preferred to concentrate based on Maize or Barley and the cows did not like the Fat rich or the pure Artificially dried grass concentrate used in the experiment. 相似文献
993.
In order to minimise the hair damage due to hair straightening process, post-treatment is recommended to protect the damaged
hair from further depreciation and breakage. However, few reported quantitatively about the effectiveness of post-treatment
after hair straightening process. Therefore, the aim of this paper will investigate the effectiveness of post-treatment methods
for chemically straightened hairs. The effectiveness will be evaluated through different analytical methods such as scanning
electron microscopy (SEM), diffuse reflectance spectrophotometry, tensile strength test and urea bisulphite solubility test
for the properties related to morphological structure, hair colour change, tensile strength as well as chemical damage respectively.
From the findings of the instrumental results, it was obvious that the application of post-treatments would improve the lustre
of the damaged hair by giving higher value in lightness when compared with the raw hair control sample. Furthermore, the strength
property of the post-treated hair increased when compared with the chemically straightened hair. This was due to the fact
that the film-forming agents of conditioning products formed a protective layer and smooth surface on the fibre surface. 相似文献
994.
Using hedonic models, we analyze the effects of proximity and noise on housing prices in neighborhoods near Hartsfield‐Jackson Atlanta International Airport during 1995–2002. Proximity to the airport is related positively to housing prices. We address complications caused by changes over time in the levels and geographic distribution of noise and by the fact that noise contours are measured infrequently. A general decline in noise boosted housing prices during 1995–2002. After accounting for proximity, house characteristics, and demographic variables, houses in noisier areas sold for less than houses subjected to less noise. Also, the noise discount is larger during 2000–2002 than 1995–1999. 相似文献
995.
China is the world’s leading producer of potatoes, growing 22% of all potatoes. Production continues to rise, owing to increases
in both land devoted to potato production and yield per hectare. Most potato production occurs in the northern and southwest
regions of the country. The processing of coarse starch is the most important component of the potato processing industry
in China, but other processing industries, such as crisps and French fries, are expanding. Major production constraints include
inadequate germplasm resources for cultivar development, the lack of high quality seed potatoes, and limited access to equipment
for mechanized cultivation, planting, fertilizing, spraying, and harvesting. Additional weaknesses in storage and transportation
technologies must be addressed, as they are the major constraints for the healthy development of the potato industry. The
introduction and improvement of these technologies will ensure the sustainable development of the potato industry in China. 相似文献
996.
Urine [12·3 g nitrogen (N) L?1], collected from native Tan sheep in rangeland of the Loess Plateau in north‐western China, was applied to vegetation patches dominated by Stipa bungeana (C3 grass) or Pennisetum flaccidum, (C4 grass) at either 0, 1·0, 2·0 or 4·0 L urine m?2 in early‐, mid‐, or late‐growing season, and herbage mass and tiller number per sample recorded, allowing calculation of the respective contributions of increases in tiller weight and tiller density to the response from N in urine. Such records were made three times in the growing season of application of urine, and at the end of the following growing season. Responses to urine were of the order of 1 and 5 kg herbage DM kg?1 N applied for S. bungeana and P. flaccidum, respectively. Except for early‐season application, responses of S. bungeana were mainly expressed in the season following urine application whereas responses of P. flaccidum tended to be expressed within the year of urine application, although with a residual response in the following year. The general pattern was for a tiller density‐mediated response in the period immediately after application, followed later by a tiller weight‐mediated response. Taken together with other recent research, S. bungeana can be considered a stress‐tolerating species with a limited response to N application and P. flaccidum an opportunist species able to capitalize on increased N supply. 相似文献
997.
The use of High Volume Instrument (HVI) to measure cotton lint characteristics produces high dimensional data. A model which
utilized Kohonen Self Organizing Maps (SOM) to visualize cotton lint HVI data, k-means clustering technique to cluster the
data and Probabilistic Neural Network (PNN) for data classification was designed and tested using Kenyan cotton lint. According
to the model the Kenyan cotton lint can be grouped into four clusters, which were successfully classified by using PNN with
a correlation coefficient (R-value) of 1. 相似文献
998.
J. G. Valdez M. A. Makuch A. F. Ordovini J. C. Frisvad D. P. Overy R. W. Masuelli R. J. Piccolo 《Plant pathology》2009,58(2):352-361
A total of 147 samples of garlic ( Allium sativum ) bulbs affected by blue mould were obtained from a variety of agroclimatic districts between December 1999 and February 2000. Penicillium species were identified using both morphological and chemotaxonomic characteristics. Penicillium allii was the predominant species isolated (81·8%) in this survey and the only species proven to be pathogenic on garlic. Other species were isolated much less frequently: P. chrysogenum (13·7%), P. brevicompactum (2·8%), P. phoeniceum (0·9%), P. aurantiogriseum (0·6%) and P. flavigenum (0·2%). Colonies of P. allii could be classified into four morphotypes and their distribution seemed to be influenced by seed trade and agricultural practices. Penicillium allii isolates were grouped into three aggressiveness phenotypes (low, medium and high) based on their ability to cause disease during field trials on susceptible (Fuego INTA) and less susceptible (Castaño INTA) garlic cultivars. The number of surviving plants at 191 days after planting and postharvest bulb weight contributed the most towards aggressiveness modelling. 相似文献
999.
Under the changing agro-climatic conditions of western Europe, the parasitic weed Phelipanche ramosa infests host crops such as tomato, hemp, tobacco and oilseed rape at an increasing rate. A Fusarium oxysporum isolate (FOG), that had effectively reduced the parasite's incidence under controlled environmental conditions, was tested in different granular formulations (pesta granules, alginate pellets) on P. ramosa parasitising tobacco under field-grown conditions. FOG reduced number and biomass of P. ramosa shoots by between 50% and 70% in three consecutive years (2006–2008). A single pesta application did not show consistent results throughout seasons; 50% reduction of P. ramosa biomass (DM) in the first year could not be repeated in the following years (20–30%). An alginate formulation applied alone performed better. However, a combination of pesta granules with alginate pellets had the highest reliable control efficacy (60–70%) of all treatments in two seasons, compared with the untreated control. Fungal population counts in soil samples did not show a close correlation to biocontrol efficacy. To understand field performance of this biocontrol agent, additional glasshouse and laboratory studies were conducted using soil from the experimental site. The glasshouse study revealed some fungistatic effects of the field soil that partly explain the reduced efficacy (-40%) in the field compared with results obtained under controlled conditions. Results show the potential of FOG for P. ramosa control. Because formulation affected the biocontrol efficacy, it may be worthwhile to test how the delivery system can be changed in order to achieve increased disease development in the field. 相似文献
1000.