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961.
962.
Culturing the longsnout seahorse, Hippocampus reidi, remains challenging because unlike most cultured seahorse species, Artemia is not an optimal first feed. Ideally, more nutritious live feeds such as wild plankton or copepods should be used, but are not always readily available. Therefore, facilities commonly utilize enriched rotifers. Numerous feed enrichment products exist, including Dan's Feed Artemia Enrichment®, (Dan's Feed) which is a blend of commercially available enrichment products. The aim of this study was to assess the survivorship, growth, and condition factor (CF) of 0–28 DPR (days post release) H. reidi fed with rotifers and Artemia enriched with Dan's Feed. This enrichment was evaluated against (1) rotifers and Artemia enriched with live alga (Isochrysis galbana), and (2) wild plankton and Artemia enriched with Dan's Feed. At 28 DPR, in terms of survivorship and growth, seahorses fed with rotifers and Artemia enriched with Dan's Feed had a lower CF and outperformed those fed rotifers and Artemia enriched with I. galbana. Seahorses fed with rotifers and Artemia enriched with Dan's Feed performed on par with those fed with wild plankton and Artemia with no significant difference in CF. These findings demonstrated that the culture of H. reidi may be feasible with rotifers and Artemia enriched with Dan's Feed . 相似文献
963.
Hyo-jin Chung Wook-hun Chung Jae-Hoon Lee Dai-Jung Chung Wo-Jong Yang A-Jin Lee Chi-Bong Choi Hwa-Seok Chang Dae-Hyun Kim Hyun Jung Suh Dong-Hun Lee Soo-Han Hwang Sun Hee Do Hwi-Yool Kim 《Journal of veterinary science (Suw?n-si, Korea)》2016,17(1):97-102
We induced percutaneous spinal cord injuries (SCI) using a balloon catheter in 45 rats and transplanted human umbilical cord blood derived mesenchymal stem cells (hUCB-MSCs) at the injury site. Locomotor function was significantly improved in hUCB-MSCs transplanted groups. Quantitative ELISA of extract from entire injured spinal cord showed increased expression of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF) and neurotrophin-3 (NT-3). Our results show that treatment of SCI with hUCB-MSCs can improve locomotor functions, and suggest that increased levels of BDNF, NGF and NT-3 in the injured spinal cord were the main therapeutic effect. 相似文献
964.
Ramasamy Harikrishnan Ju‐Sang Kim Man‐Chul Kim Moon‐Soo Heo Chellam Balasundaram 《Journal of the World Aquaculture Society》2012,43(2):259-269
The effect of different solvent‐based (methanol, ethanol, and aqueous) extracts of Liriope platyphylla at 0, 0.1, 1.0, and 2.0 mg doses on hematology and innate immune response in olive flounder, Paralichthys olivaceus, against Flexibacter maritimus is reported. The red blood cells and white blood cells significantly increased with ethanol and aqueous extracts with any dose against F. maritimus while the hematocrit level significantly increased with methanol or ethanol extracts. However, the hemoglobin content significantly increased irrespective of the doses and type of extracts, whereas the mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration significantly decreased. The lymphocytes and monocytes significantly increased in all doses and extracts, whereas neutrophils increased in ethanol or aqueous extracts. However, the thrombocytes level neither the doses nor extracts did not significant changes to the control against pathogen. Total protein and globulin levels significantly increased with all the doses of ethanol extract while does not significant change in methanol extract. The phagocytic activity and complement activity were significantly enhanced with any dose of ethanol extract while with aqueous extract it was only at 1.0 and 2.0 mg doses. At all the doses of each extract significantly enhanced the leucocytes activity against F. maritimus. The results confirm that the ethanolic and aqueous extracts of L. platyphylla stimulate the immune response against F. maritimus in P. olivaceus. 相似文献
965.
966.
967.
There has been a decline in tree growth since the operation of factories atPinus thunbergii forests around a petrochemical industrial complex in Korea. This study was carried out to investigate the effects of air
pollution on tree ring width and ring density ofPinus thunbergii. Soft X-ray densitometrical method was used. Decline of ring width was the highest during 3 years immediately after the operation
of factories. The percentage of decrease was almost bigger immediately after operation as compared with before. Maximum density
(MAXD), and the difference (DD) between maximum density and minimum density (MIND) generally decreased since operation of
factories, while minimum density increased in the beginning of operation of factories. There was a significant correlation
between ring width and high temperature, and precipitation in the beginning of growing season, respectively. There was also
a negative correlation between annual mean concentration of SO2 and ring width at 5% level (r=−0.627*). It is suggested that the decline of ring width after operation of factories was due to compound factors of air pollution
and climate. The effect of other factors should be still more studied.
A part of this paper was presented at the International Workshop on Asian and Pacific Dendrochronology on March 4–9, 1995
in Tsukuba (Forestry and Forest Products Research Institute), Japan. 相似文献
968.
969.
This study examined the distribution of water-extractable Al in soils from forest sites near Nagoya in Aichi Prefecture. The
mean concentrations of water-extractable Al in surface soils varied markedly among sites, with the values at site FGB (126 mg/kg)
higher than those at sites FG (11.8 mg/kg) and FCB (33.8 mg/kg). Comparisons of the acid buffer capacity of vegetation at
the sites revealed that forest cover has a higher capacity for neutralization than the denuded state. We found that the effects
of acidic accumulation in the surface soils of suburban forests might depend on vegetation history, and that forest soils
that once had no vegetation cover accumulated labile Al due to acidification. The phenomenon was particularly distinct on
granite bedrock. 相似文献
970.
Nagel JM Griffin KL Schuster WS Tissue DT Turnbull MH Brown KJ Whitehead D 《Tree physiology》2002,22(12):859-867
Despite its recent expansion in eastern US forests, red maple (Acer rubrum L.) generally exhibits a low leaf photosynthetic rate, leaf mass per unit area (LMA) and leaf nitrogen concentration ([N]) relative to co-occurring oaks (Quercus spp.). To evaluate these differences from the perspective of leaf energy investment, we compared leaf construction cost (CC) and leaf maintenance cost (MC) with leaf photosynthetic rate at saturating photon flux density and ambient CO2 partial pressure (Amax) in red maple and co-occurring red oak (Quercus rubra L.) and chestnut oak (Quercus prinus L.). We also examined relationships among leaf physiological, biochemical and structural characteristics of upper-canopy leaves of these three species at lower (wetter) and upper (drier) elevation sites of a watershed in the Black Rock Forest, Cornwall, NY, USA. Although A(max), leaf [N], leaf carbon concentration ([C]) and LMA were significantly less in red maple than in either oak species at both sites, CC per unit leaf area of red maple was 28.2 and 35.4% less than that of red oak at the lower and upper site, respectively, and 38.8 and 32% less than that of chestnut oak at the lower and upper site, respectively. Leaf MC per unit leaf area, which was positively associated with leaf CC (r2 = 0.95), was also significantly lower in red maple than in either oak species at both sites. When expressed per unit leaf area, A(max) was positively correlated with both CC (r2 = 0.65) and MC (r2 = 0.59). The cost/benefit ratio of CC/Amax of red maple was significantly less than that of chestnut oak at the lower site, however, CC/A(max) did not exhibit any significant interspecific differences at the upper site. Expressed per unit leaf area, CC was correlated positively with LMA (r2 = 0.90), leaf [N] (r2 = 0.97), and leaf [C] (r2 = 0.89), and negatively correlated with leaf molar carbon to nitrogen ratio (r2 = 0.92). Combined with red maple's general success in many oak-dominated forests, our findings suggest that reduced leaf-level photosynthetic capacity and related leaf characteristics in red maple are partially balanced by lower energy and resource requirements for leaf biomass construction and maintenance, which could enhance the competitive success of this species. 相似文献