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991.
Kifah Jumaah Odhaib Kazeem Dauda Adeyemi Muideen Adewale Ahmed Muhammad Faseleh Jahromi Shokri Jusoh Anjas Asmara Samsudin Abdul Razak Alimon Halimatun Yaakub Awis Qurni Sazili 《Tropical animal health and production》2018,50(5):1011-1023
The objective of this study was to determine the effects of dietary supplementation of Nigella sativa L. seeds, Rosmarinus officinalis L. leaves and their combination on rumen metabolism, nutrient intake and digestibility, growth performance, immune response and blood metabolites in Dorper lambs. Twenty-four entire male Dorper lambs (18.68?±?0.6 kg, 4–5 months old) were randomly assigned to a concentrate mixture containing on a dry matter basis either, no supplement (control, T1), 1% R. officinalis leaves (T2), 1% N. sativa seeds (T3) or 1% R. officinalis leaves +1% N. sativa seeds (T4). The lambs had ad libitum access to urea-treated rice straw (UTRS) and were raised for 90 days. Supplemented lambs had greater (P?< 0.05) intake of DM and UTRS than the control lambs. The T4 lambs had lower (P?< 0.05) nutrient digestibility than those fed other treatments. Total and daily weight gain was greater (P?< 0.05) in T2 lambs than those fed other diets. The T3 and T4 lambs had greater (P?< 0.05) ruminal pH than the T1 and T2 lambs. Supplemented lambs had lower (P?<?0.05) ruminal total volatile fatty acids, acetate, propionate, NH3-N and C18:0 than the control lambs. The T4 lambs had lower (P?< 0.05) population of Fibrobacter succinogenes, Ruminococcus albus, methanogens and total protozoa compared with those fed other diets. Supplemented lambs had lower (P?< 0.05) neutrophils, basophils and serum urea and greater (P?<?0.05) serum IgA and IgG compared with the control lambs. The current results emphasised the variation in the efficacy of medicinal plants in ruminant nutrition. 相似文献
992.
Nathaly Enciso Luciana L. K. Ostronoff Guillermo Mejías Leticia G. León María Luisa Fermín Elena Merino Cristina Fragio Luis Avedillo Concepción Tejero 《Veterinary research communications》2018,42(1):29-38
Adult Mesenchymal Stem Cells (MSC) are cells that can be defined as multipotent cells able to differentiate into diverse lineages, under appropriate conditions. These cells have been widely used in regenerative medicine, both in preclinical and clinical settings. Initially discovered in bone marrow, MSC can now be isolated from a wide spectrum of adult and foetal tissues. Studies to evaluate the therapeutic potential of these cells are based on their ability to arrive to damaged tissues. In this paper we have done a comparative study analyzing proliferation, surface markers and OCT4, SOX9, RUNX2, PPARG genes expression in MSC cells from Bone marrow (BMMSC) and Adipose tissue (ASC). We also analyzed the role of Stem Cell Factor (SCF) on MSC proliferation and on ASCs metalloproteinases MMP-2, MMP-9 secretion. Healthy dogs were used as BMMSC donors, and ASC were collected from omentum during elective ovariohysterectomy surgery. Both cell types were cultured in IMDM medium with or without SCF, 10% Dog Serum (DS), and incubated at 38 °C with 5% CO2. Growth of BMMSCs and ASCs was exponential until 25–30 days. Flow citometry of MSCs revealed positive results for CD90 and negative for CD34, CD45 and MCH-II. Genes were evaluated by RT-PCR and metalloproteinases by zymografy. Our findings indicate morphological and immunological similarities as well as expression of genes from both origins on analyzed cells. Furthermore, SCF did not affect proliferation of MSCs, however it up-regulated MMP-2 and MMP-9 secretion in ASCs. These results suggest that metalloproteinases are possibly essential molecules pivoting migration. 相似文献
993.
As the levels of radioactivity in seafood have fallen back into the safe range, Fukushima fisheries are considering reopening. However, even if seafood from the Fukushima area were sufficiently safe to distribute to seafood markets, its value may be undermined because of the damage done to its reputation by the Fukushima disaster. We quantified consumers’ preferences for seafood from Fukushima and adjacent prefectures to examine the extent of the reputational damage to Fukushima seafood. We conducted a choice experiment to measure consumers’ willingness to pay for seafood from the Fukushima area. We also measured the impact of displaying ecolabels [Marine Stewardship Council (MSC) and Marine Eco-label Japan (MEL)] on Fukushima products. The results indicated that Fukushima products are considerably discounted compared with products displayed as domestic; even products from adjacent prefectures are substantially discounted. By contrast, consumers positively evaluated locally labeled products. We also found that demersal fish are discounted more than pelagic fish that inhabit the ocean surface off the shore of Fukushima. 相似文献
994.
Yigang Hu Zengru Wang Qi Wang Shiping Wang Zhishan Zhang Zhenhua Zhang Yang Zhao 《Journal of Soils and Sediments》2017,17(2):326-339
Purpose
Changes in bioactive soil C pools and their temperature sensitivities will dominate the fate of soil organic C in a warmer future, which is not well understood in highland ecosystems. This study was conducted in order to evaluate climate change, especially cooling effects, on soil labile organic C (LOC) pools in a Tibetan alpine meadow.Materials and methods
A short-term reciprocal translocation experiment was implemented to stimulate climate warming (downward translocation) and cooling (upward translocation) using an elevation gradient on the Tibetan Plateau. Variations in soil microbial biomass C (MBC), dissolved organic C (DOC) and LOC were analyzed.Results and discussion
Over the range of soil temperature from 0.02 to 5.5 °C, warming averagely increased soil MBC, DOC and LOC by 15.3, 17.0 and 3.7 % while cooling decreased them by 11.0, 11.9 and 3.2 %, respectively. Moreover, warming generally increased the proportion of DOC in LOC but cooling had an opposite effect, while the response of the MBC proportion to DOC and LOC varied depending on vegetation type. Soil MBC, DOC and LOC pools were positively related to soil temperature and showed a hump-shaped relationship with soil moisture with a threshold of about 30–35 %. Although soil DOC was more sensitive to warming (5.1 % °C?1) than to cooling (3.0 % °C?1), soil LOC showed a symmetrical response due to regulation by soil moisture.Conclusions
Our results indicated that climate change would not only change the size of soil LOC pools but also their quality. Therefore, cooling effects and regulation of soil moisture should be considered to evaluate the fate of soil organic C in Tibetan alpine meadows in a warmer future.995.
Three slow-growing legume trees used for desert reforestation and urban gardening in the Sonoran Desert of Northwestern Mexico
and the Southwestern USA were evaluated whether their growth can be promoted by inoculation with plant growth-promoting bacteria
(Azospirillum brasilense and Bacillus pumilus), unidentified arbuscular mycorrhizal (AM) fungi (mainly Glomus sp.), and supplementation with common compost under regular screenhouse cultivation common to these trees in nurseries. Mesquite
amargo (Prosopis articulata) and yellow palo verde (Parkinsonia microphylla) had different positive responses to several of the parameters tested while blue palo verde (Parkinsonia florida) did not respond. Survival of all tree species was over 80% and survival of mesquite was almost 100% after 10 months of cultivation.
Inoculation with growth-promoting microorganisms induced significant effects on the leaf gas exchange of these trees, measured
as transpiration and diffusive resistance, when these trees were cultivated without water restrictions. 相似文献
996.
Hyper-spectral remote sensing to monitor vegetation stress 总被引:1,自引:0,他引:1
Hong-Yan Ren Da-Fang Zhuang Jian-Jun Pan Xue-Zheng Shi Hong-Jie Wang 《Journal of Soils and Sediments》2008,8(5):323-326
Background, aim, and scope Vegetation stress diagnoses based on plant sampling and physiochemical analysis using traditional methods are commonly time-consuming,
destructive and expensive. The measurement of field spectral reflectance is one basis of airborne or spaceborne remote sensing
monitoring.
Materials and methods In this study, paddy plants were grown in the barrels evenly filled with 10.0 kg soil that was mixed respectively with 0,
2.5 × 207.2 and 5.0 × 207.2 mg Pb per 1,000 g soil. Rice canopy spectra were gathered by mobile hyper-spectral radiometer
(ASD FieldSpec Pro FR, USA). Meanwhile, canopy leaves in the field-of-view (FOV) of spectroradiometer were collected and then
prepared in the laboratory, (1) for chlorophyll measurement by Model 721 spectrophotometer, and (2) for Pb determination by
atomic absorption spectrophotometer (SpectraAA-220FS).
Results and discussion Canopy spectral reflectance in the region of visible-to-near-infrared light (VNIR) increased, because ascended Pb concentration
caused the decrease of canopy chlorophyll content. In the agro-ecosystem, however, heavy metal contamination is presented
typically as mixture and their interactions strongly affect actually occurring effects. Normalized spectral absorption depth
(D
n), and shifting distance (DS) of red edge position (REPs) revealed the differences in Pb concentration for canopy leaves,
especially at the early tillering stage. Due to insufficient biomass of rice plants, the 30th day was not reliable enough
for the selection of crucial growth stages. Some special sensitive bands might be omitted at the same time because of limited
sample sets.
Conclusions Our initial experiments are still too few in the amounts of both metals and plants neither to build accurate prediction models
nor to discuss the transformation from ground to air/spaceborne remote sensing. However, we are pleased to communicate that
ground remote sensing measurements would provide reliable information for the estimation of Pb concentration in rice plants
at the early tillering stage when proper features (such as DS and D
n) of reflectance spectra are applied.
Recommendations and perspectives Hyper-spectral remote sensing is a potential and promising technology for monitoring environmental stresses on agricultural
vegetation. Further ground remote sensing experiments are necessary to evaluate the possibility of hyper-spectral reflectance
spectroscopy in monitoring different kinds of metals’ stress on various plants. 相似文献
997.
In this work, dopamine hydrochloride, an environmental friendly compound, was applied on polyester fabric through conventional simple impregnation method in alkaline solution (pH=8.5) at room temperature. In situ spontaneous oxidative polymerization of dopamine form polydopamine (PDA) along with aminolysis of polyester fabric surface. Also, a range of colored polyester fabric were successfully achieved by formation of polydopamine adhesive coating layer at different concentration of dopamine hydrochloride (0.001-4 g/l). Fourier transform infrared spectroscopy and field emission scanning electron microscopy showed deposition of polydopmaine on the polyester fabric surface. The modified colored polyester fabric showed reasonable durability against washing, rubbing and light. The treated polyester fabric with 2 g/l dopamine hydrochloride as optimum concentration indicated not only lower spreading time for water droplet and electrical resistance with higher tensile strength but also very good bactericidal activity against Staphylococcus aureus and Escherichia coli. 相似文献
998.
In order to prevent surgical complications due to microbial infections, we have developed polypropylene suture grafted with silver nanoparticles (PPsuture/Ag nanocomposite) by a simple immersion procedure. Physical and mechanical properties of developed suture are investigated. Suture surface characteristics are examined by scanning electron microscopy (SEM) imaging and atomic force microscopy (AFM). Silver content on suture surface was determined by Inductively coupled plasma atomic emission spectroscopy (ICP-AES). The mechanical properties of developed antibacterial PP suture/Ag were studied. We note that proposed silver coating method has not affected mechanical performances of suture. Antimicrobial performances of PP suture/Ag nanocomposites against S. aureus and E. coli colonies were also investigated. 相似文献
999.
Zhi-Wei Wang Lei Gao Hai Zhou Liu Shi Yong Mei Yuan Zhou Chang Ping Xiang Ting Wang 《Euphytica》2012,186(2):313-320
A male sterile plant appeared in the radish breeding program at the Hubei Academy of Agricultural Sciences, Hubei, China.
In its progeny, a two-type (half of plants male sterile, the other half male fertile) line 01GAB was established. An F2 population of 260 plants from a cross of male-sterile 01GAB and a male fertile line 9802H segregated for male fertility in
a 3:1 ratio indicating that fertility was restored by a single dominant gene, here designated RsMs. A PCR-based DNA marker specific to the male fertility Rfob gene in 9802H was absent in 01GAB. Linkage analysis placed the RsMs locus 10.7 cM away from the Rfo locus. In an F2 population of hybrids between 01GAB and male fertile 9802B, a co-dominant DNA marker for the RSultr3.2A (a radish sulfate transporter gene) locus was linked to the RsMs locus at 1.5 cM suggesting that fertility restoration in 01GAB was located in the region with known male sterility restorers
in radish. However, no maintainer for the 01GAB source of male sterility has been identified so far. Cytological observations
have shown that the abnormalities in male sterile anthers first appeared in tapetum at the tetrad stage, followed by a hypertrophy
of the tapetal cells at the vacuolate microspore period. These results suggest that male sterility in 01GAB is likely to be
genetic in nature, or it may represent a new type of the cytoplasmic male sterility. 相似文献
1000.
Zhongyi Sun Xiufeng Wang Haruhiko Yamamoto Jiquan Zhang Hiroshi Tani Guosheng Zhong Shuai Yin 《Paddy and Water Environment》2017,15(1):181-191
Rice is the second largest staple crop in the world and therefore plays an important role in food security. As a thermophilic crop, rice is sensitive to temperature changes. Thus, research on the chilling damage of rice is essential. The Sanjiang Plain is an emerging rice production area and is located at high latitudes in China, the world’s largest rice-producing country. Landsat data were used to extract rice-planting area from 1985 to 2015. MODIS 13Q1, which was uniformly distributed during the growing period of rice, was used to obtain NDVI values of paddies during 2002–2015. Dynamic Identification Index of sterile-type chilling damage and monitoring standard of delayed-type chilling damage were the proposed methods used in this paper, which were used to judge the chilling damage of rice. The results show that in the study region, the rice-planting area in 2015 is nearly 12 times larger than that in 1985. Delayed-type chilling damage occurred in 2002 and 2009, while sterile-type chilling damage occurred in 2005, 2006, 2009, 2010, 2014, and 2015. Comparing with the prevalent meteorological standards, the results indicate that the index and standards proposed in this paper are precise, applicable, and more sensitive than them. The method is a macroscopic and accurate method to identify chilling damage in rice and can also provide a scientific basis to ensuring the stability of rice yield. 相似文献