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排序方式: 共有409条查询结果,搜索用时 15 毫秒
111.
Miho Kojima Hiroyuki Yamamoto Kayo Okumura Yasuhisa Ojio Masato Yoshida Takashi Okuyama Toshihiro Ona Kenji Matsune Kentaro Nakamura Yuji Ide Sri Nugroho Marsoem Mohd Hamami Sahri Yusuf Sudo Hadi 《Journal of Wood Science》2009,55(6):417-424
We investigated the feasibility of using several fast-growing tropical or subtropical hardwood species for timber production by measuring key wood qualities in relationship to the high rates of lateral growth. The trees tested were sampled from even-aged plantations of Acacia mangium, A. auriculiformis, hybrid Acacia (A. mangium × A. auriculiformis), Eucalyptus grandis, E. globulus, and Paraserianthes falcataria (Solomon and Java origin) that had already reached commercial harvesting age. The released strain of the surface growth stress (RS), xylem density (XD), microfibril angle (MFA), and fiber length (FL) were measured at the outermost part of the xylem at breast height in each tree. Results were then compared to the lateral growth rate (radius/age) at breast height, which provides a relative indicator of the amount of tree growth per year. Our findings indicated that RS was constant, regardless of lateral growth rate in each species. Similar results were observed for XD, MFA, and FL, with a few exceptions, suggesting that high growth rates do not intrinsically affect the wood properties of fast-growing tropical or subtropical species that have reached harvesting age. However, special attention must be paid to patterns of xylem maturation when developing plantations of such species. 相似文献
112.
Khairul Hafiz Mohd Yusoff Arifin Abdu Katsutoshi Sakurai Sota Tanaka Yumei Kang 《Soil Science and Plant Nutrition》2013,59(4):357-368
The morphological and chemical properties of homegardens in the beach ridges with interspersed swales (BRIS) soils were evaluated in order to find a clue for developing sustainable agricultural management. Field survey and soil sampling were conducted at the homegardens and secondary forests in Sungai Ular Village and in the experimental farm of Malaysian Agriculture Research Institute (MARDI), Cherating Station. Chemical fertilizers including ash, charcoal waste and plant litter were applied to the homegardens in both the inland-ward area (HG-I) and in the shoreline area (HG-S). Manure was applied in HG-I and seafood waste from fish processing was buried in the soils in HG-S. High correlation was found between total carbon (T-C) and cation exchange capacity (CEC), indicating soil organic matter was the determinant factor for CEC in the very sandy BRIS soils. The levels of T-C, total nitrogen (T-N), and CEC at 0–10 cm in HG-I in parallel with increasing ages of homegardens. The soils in 0–10 cm and 20–30 cm showed higher levels of T-C and T-N with higher C/N ratios in HG-I than in HG-S and the MARDI farm. The high levels of exchangeable Ca, Mg, and K in HG-I compared with the MARDI farm, suggesting that improved CEC with increasing soil organic matter in HG-I heighten the retention of basic cations supplied as chemical fertilizer, ash, and manure. The level of available P was higher in HG-S than HG-I, attributed by the seafood waste application in the shoreline area. Thus, on the BRIS, the levels of soil organic matter and nutrients can be sustained by the homegarden management although it cannot be regarded as a closed system compared with those in the other tropical regions because chemical fertilizer was used and a certain amounts of nutrients seemed to leach down beyond plant rooting depth. 相似文献
113.
Mehdi Rasoli Swee Keong Yeap Sheau Wei Tan Hassan Moeini Aini Ideris Mohd Hair Bejo Noorjahan Banu Mohamed Alitheen Pete Kaiser Abdul Rahman Omar 《Comparative immunology, microbiology and infectious diseases》2014
Newcastle disease (ND) is a highly contagious avian disease and one of the major causes of economic losses in the poultry industry. The emergence of virulent NDV genotypes and repeated outbreaks of NDV in vaccinated chickens have raised the need for fundamental studies on the virus–host interactions. In this study, the profiles of B and T lymphocytes and macrophages and differential expression of 26 immune-related genes in the spleen of specific-pathogen-free (SPF) chickens, infected with either the velogenic genotype VII NDV strain IBS002 or the genotype VIII NDV strain AF2240, were evaluated. A significant reduction in T lymphocyte population and an increase in the infiltration of IgM+ B cells and KUL01+ macrophages were detected in the infected spleens at 1, 3 and 4 days post-infection (dpi) (P < 0.05). The gene expression profiles showed an up-regulation of CCLi3, CXCLi1, CXCLi2 (IL-8), IFN-γ, IL-12α, IL-18, IL-1β, IL-6, iNOS, TLR7, MHCI, IL-17F and TNFSF13B (P < 0.05). However, these two genotypes showed different cytokine expression patterns and viral load. IBS002 showed higher viral load than AF2240 in spleen at 3 and 4 dpi and caused a more rapid up-regulation of CXCLi2, IFN-γ, IL-12α, IL-18, IL-1β, iNOS and IL-10 at 3 dpi. Meanwhile, the expression levels of CCLI3, CXCLi1, IFN-γ, IL-12α, IL-1β and iNOS genes were significantly higher in AF2240 at 4 dpi. In addition, the expression levels of IL-10 were significantly higher in the IBS002-infected chickens at 3 and 4 dpi. Hence, infection with velogenic genotype VII and VIII NDV induced different viral load and production of cytokines and chemokines associated with inflammatory reactions. 相似文献
114.
Lawan Adamu Noraniza Mohd Adzahan Abdullah Rasedee Bashir Ahmad 《Journal of Equine Veterinary Science》2014
Endurance racing is one long-distance event among the equine sporting activities associated with severe injuries and metabolic derangements that impede the health status of horses participating in the event. Therefore, this study evaluated the physical parameters and risk factors associated with the elimination of Arabian and crossed Arabian endurance horses during a 120-km race. Fifty-three Arabian and crossed Arabian endurance horses aged 6 to 15 years old participated in an endurance race of 120 km. All the horses were examined and found fit according to Fédération Équestre Internationale (FEI) regulations. After the endurance race 14 Arabian endurance horses completed the race successfully while 31 Arabian and crossed Arabian were eliminated. Their speed and heart rates were significantly higher (P < .0001). There were significant differences in skin recoil (P < .0395), color of mucous membrane (P < .0189), intestinal motility (P < .0124), and capillary refill time (P < .0082). There also were significant differences in age (P < .0018), breed (P < .0119), and equine establishments (P < .0205) among the eliminated horses and the Arabian and crossed Arabian endurance horses that successfully completed the race. In conclusion, the physical parameters and risk factors were significantly associated with the elimination of Arabian and crossed Arabian endurance horses. Therefore, close monitoring of the physical parameters and risk factors are essential in order to improve the performance of Arabian and crossed Arabian horses, and further studies are required on other associated parameters. 相似文献
115.
Postseismic viscoelastic rebound 总被引:3,自引:0,他引:3
The sudden appearance of a dislocation, representing an earthquake, in an elastic layer (the lithosphere) overriding a viscoelastic half space (the asthenosphere) is followed by time-dependent surface deformation, which is very similar to in situ postseismic deformation. The spectacular postseismic deformation following the large Nankaido earthquake of 1946 yields for the asthenosphere a viscosity of 5 x 10(19) poise and a 50 percent relaxation of the shear modulus. Large thrust type earthquakes may provide, in the future, a new method for exploring the rheology of the earth's upper mantle. 相似文献
116.
117.
对新疆吐鲁番市万亩人工固沙林的观测表明,风速降低39%~68%,粗糙度提高13.8~27.3cm,沙的吹失减少98.2%~99.2%,空气相对湿度增加9.46%,绝对温度增加1.61hPa,饱和差减少2.03hPa,日蒸发减少9.9mm,固定了流沙,改善了小气候,保护了附近的村庄和农田,生态效益显著。 相似文献
118.
119.
This study hypothesizes that melatonin with exogenous progesterone (CIDR) can improve follicular, luteal, ovarian and uterine haemodynamic of heat-stressed cows. Holstein cows (N = 12) studied for two spontaneous oestrous cycles during winter then divided equally during summer into the CIDR group received CIDR for 7 days and the melatonin group (Mel) received three injections of melatonin (75 mg/head) at the CIDR insertion, removal and ovulation days. Blood samples were collected to assay oestradiol (E2), progesterone (P4) and nitric oxide (NO). On day 0 (Ovulation), Mel had more small follicles (p < .05), higher ipsilateral and contralateral ovarian arteries (Ov.A.) peak systolic velocity (PSV), higher ipsilateral uterine artery (Ut.A.) PSV (p = .031) and blood flow volume (BFV), also Mel elevated contralateral Ut.A. PSV and BFV (p < .0001) but lowered contra Ut.A. pulsatility index (PI, p < .0001), E2 (p < .01) and NO (p < .0001). Mel increased the corpus luteum diameter (CL, p < .001), coloured area (p < .007) and P4 (p < .0001) on day 5 and reduced them (p < .05; p < .01) on Day 14. On day 10, Mel obtained CL diameter (p < .03) and coloured area (p < .002) of spontaneous that was higher than CIDR and decreased P4 (p < .003). Mel increased CL diameter, area and coloured area and decreased them thereafter. Mel increased the ipsilateral ovarian and uterine arteries PSV and BFV before ovulation and until day 8. Mel increased P4 and decreased NO until days 6 and 14. In conclusion, the improvement in follicular, luteal, ovarian and uterine haemodynamic and the decrease of NO production proved our hypothesis Melatonin doses higher than 75 mg/head is recommended to improve the heat-stressed cow's fertility. 相似文献
120.
Sandip Kumar Khurana Anju Sehrawat Ruchi Tiwari Minakshi Prasad Baldev Gulati Muhammad Zubair Shabbir Rajesh Chhabra Kumaragurubaran Karthik Shailesh Kumar Patel Mamta Pathak Mohd. Iqbal Yatoo Vivek Kumar Gupta Kuldeep Dhama Ranjit Sah Wanpen Chaicumpa 《The Veterinary quarterly》2021,41(1):61
Brucellosis is a zoonotic disease of great animal welfare and economic implications worldwide known since ancient times. The emergence of brucellosis in new areas as well as transmission of brucellosis from wild and domestic animals is of great significance in terms of new epidemiological dimensions. Brucellosis poses a major public health threat by the consumption of non-pasteurized milk and milk products produced by unhygienic dairy farms in endemic areas. Regular and meticulous surveillance is essentially required to determine the true picture of brucellosis especially in areas with continuous high prevalence. Additionally, international migration of humans, animals and trade of animal products has created a challenge for disease spread and diagnosis in non-endemic areas. Isolation and identification remain the gold standard test, which requires expertise. The advancement in diagnostic strategies coupled with screening of newly introduced animals is warranted to control the disease. Of note, the diagnostic value of miRNAs for appropriate detection of B. abortus infection has been shown. The most widely used vaccine strains to protect against Brucella infection and related abortions in cattle are strain 19 and RB51. Moreover, it is very important to note that no vaccine, which is highly protective, safe and effective is available either for bovines or human beings. Research results encourage the use of bacteriophage lysates in treatment of bovine brucellosis. One Health approach can aid in control of this disease, both in animals and man. 相似文献