The effect of short day treatments on containerized Douglas-fir morphology,physiology and phenology     

Turner  Jennifer  Mitchell  Stephen J. 《New Forests》2003,26(3):279-295

The effect of short day treatments (blackout) on Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) container seedlings at the time of lift and following cold storage was investigated. Variables measured included height, root collar diameter (RCD), root growth capacity (RGC), photosynthetic efficiency after –18 °C freezing (PEF), and days to terminal bud break (DBB). From one to four blackout dormancy induction treatments were started on three dates (July 12, July 26, and August 10) with 10 or 20 d between multiple blackouts. Increasing the number of blackout treatments resulted in lower RCD, lower DBB in the late winter/early spring, and higher PEF in the early fall. Later blackout start dates decreased PEF in the early fall, and increased overall height and late fall RGC as compared to earlier blackout start dates. Nurseries growing Douglas-fir seedlings from coastal Pacific Northwest provenances should be aware that blackout regimes can decrease RGC in the late fall, and cause quicker dormancy release in the early spring. Coastal Douglas-fir can be lifted and planted in the early fall, when RGC and DBB are relatively high. If planting between February and April is necessary, seedlings given blackout should be cold stored in January to maintain an adequate level of dormancy, RGC and PEF.  相似文献   

Immunohistochemical Expression of Growth Factors in the Follicular Wall of Normal and Cystic Ovaries of Sows          下载免费PDF全文

FJF Sant'Ana  JL Reis Junior  GR Blume  EJ Gimeno  F Rey  HH Ortega 《Reproduction in domestic animals》2015,50(2):327-332

The expression of growth factors was evaluated immunohistochemically in normal and cystic ovaries of sows. The immunohistochemically stained area (IHCSA) was quantified by image analysis to analyse the expression of these proteins in the follicular wall of secondary, tertiary and cystic follicles. IGF‐I immunoreactivity was strong in the granulosa cell layer (GC), moderate in the theca interna (TI) and mild in the theca externa (TE) of the normal follicles. There was severe reduction of the labelling to IGF‐I in the GC of the follicular and luteinized cysts. In the normal follicles, the reactivity for IGF‐II was very similar to pattern noted in IGF‐I. There was reduction of the IHCSAs in the GC of the follicular and luteinized cysts, but the decrease was not significant. The staining of the IGF‐II in the TI and TE of the cysts was increased, in comparison with normal follicles. The IHCSAs for VEGF were higher in the GC and TE of the normal follicles in contrast to TI, but this difference was noted only in the tertiary follicle. The VEGF reactivity increased in the GC of the cysts, in relation to normal follicles. The results of the current study show that the formation of ovarian cysts in sows is associated with alterations in the immunohistochemical expression of some growth factors.  相似文献   

Effects of unilateral ovariectomy on recruitment and growth of follicles in the rainbow trout,Oncorhynchus mykiss     

C. R. Tyler  J. J. Nagler  T. G. Pottinger  M. A. Turner 《Fish physiology and biochemistry》1994,13(4):309-316

Virgin female rainbow trout, Oncorhynchus mykiss, were unilaterally ovariectomised at various stages of ovarian development to investigate the effect of the removal of one ovary on subsequent recruitment and growth of follicles in the remaining ovary. The right ovary was removed from groups of 12–15 fish, 12, 7 and 4 months before they were due to ovulate, and the gonadosomatic index and follicle number and size determined just prior to ovulation. There were no differences in fecundity or follicle size in fish unilaterally ovariectomised at 12 and 7 months prior to ovulation compared to the controls. However, in the females unilaterally ovariectomised 4 months prior to ovulation, the remaining ovary either had the normal number of follicles for a single ovary but of a significantly larger size than follicles in the controls, or alternatively had almost 70% more than the normal number of vitellogenic follicles but comprising two distinctly different size populations. Differences in plasma oestradiol-17β concentrations at the final sample were seen only in females unilaterally ovariectomised 4 months prior to ovulation, where the levels were significantly lower than both the sham operated and control fish (p < 0.05). These data show that in the rainbow trout, complete compensatory ovarian hypertrophy following unilateral ovariectomy can occur throughout a major part of ovarian development, but that follicle recruitment is limited to stages up to (and therefore fecundity is determined by) mid-vitellogenesis.  相似文献   

A Large‐scale,Rapid Public Health Response to Rabies in an Organ Recipient and the Previously Undiagnosed Organ Donor     

R. M. Wallace  D. Stanek  S. Griese  D. Krulak  N. M. Vora  L. Pacha  V. Kan  M. Said  C. Williams  T. H. Burgess  S. S. Clausen  C. Austin  J. Gabel  M. Lehman  L. N. Finelli  G. Selvaggi  P. Joyce  F. Gordin  D. Benator  A. Bettano  S. Cersovsky  C. Blackmore  S. V. Jones  B. D. Buchanan  A. I. Fernandez  D. Dinelli  K. Agnes  A. Clark  J. Gill  M. Irmler  D. Blythe  K. Mitchell  T. J. Whitman  M. J. Zapor  S. Zorich  C. Witkop  P. Jenkins  P. Mora  D. Droller  S. Turner  L. Dunn  P. Williams  C. Richards  G. Ewing  K. Chapman  C. Corbitt  T. Girimont  R. Franka  S. Recuenco  J. D. Blanton  K. A. Feldman 《Zoonoses and public health》2014,61(8):560-570

This article describes and contrasts the public health response to two human rabies cases: one organ recipient diagnosed within days of symptom onset and the transplant donor who was diagnosed 18 months post‐symptom onset. In response to an organ‐transplant‐related rabies case diagnosed in 2013, organ donor and recipient investigations were conducted by multiple public health agencies. Persons with potential exposure to infectious patient materials were assessed for rabies virus exposure. An exposure investigation was conducted to determine the source of the organ donor's infection. Over 100 persons from more than 20 agencies spent over 2700 h conducting contact investigations in healthcare, military and community settings. The 564 persons assessed include 417 healthcare workers [5.8% recommended for post‐exposure prophylaxis (PEP)], 96 community contacts (15.6% recommended for PEP), 30 autopsy personnel (50% recommended for PEP), and 21 other persons (4.8% recommended for PEP). Donor contacts represented 188 assessed with 20.2% recommended for PEP, compared with 5.6% of 306 recipient contacts recommended for PEP. Human rabies cases result in substantial use of public health and medical resources, especially when diagnosis is delayed. Although rare, clinicians should consider rabies in cases of encephalitis of unexplained aetiology, particularly for cases that may result in organ donation.  相似文献   

The mbuna cichlids of Lake Malawi: a model for rapid speciation and adaptive radiation   总被引：6，自引：0，他引：6  

Martin J. Genner  & George F. Turner 《Fish and Fisheries》2005,6(1):1-34

Mbuna, the dominant fishes on the rocky shores of Lake Malawi, have become a major ‘model system’ for the study of rapid speciation and adaptive radiation. At least 295 putative species are known, of which more than 200 remain undescribed. There is no good evidence for monophyly in the mbuna, rather mitochondrial DNA phylogenies indicate that they are polyphlyetic with respect to benthic feeding cichlids of the genera Aulonocara, Alticorpus and some species of Lethrinops. Male mbuna hold territories for 18 months or more and breed year‐round. All species are maternal mouthbrooders, but females do not guard free‐swimming young. Mbuna are polygamous (both sexes). There is sexual dimorphism in size, colour and fin length, and many species show within‐population colour polymorphism. Mbuna genera are largely differentiated on the basis of head, jaw and tooth morphology, but congeneric species are generally distinguished by male colour. Many morphologically specialized forms have broad diets and often feed on common easily obtainable resources. While it is likely that dietary and habitat niche partitioning contributes to species coexistence, this has never clearly been demonstrated under experimental conditions. Populations on spatially separated habitat patches are often genetically differentiated, probably because most species are specialized for life on rocky shores, and lack a dispersal phase in their life histories. Males seem to disperse more than females, but are able to home several kilometres back to their territories. Some closely related ecologically equivalent allopatric populations are differentiated in male colour. Those tested have been shown to mate at least partially assortatively. Sexual selection acting on male colour seems the most plausible mechanism for initial species divergence. The same colour forms seem to have arisen several times, suggesting frequent parallel evolution. The main conservation threat to mbuna at present seems to be translocation of species within the lake as a result of the aquarium trade. However, deleterious effects on indigenous populations are not documented. In the long run, sedimentation, pollution, introduction of alien species and the development of targeted food fisheries could be more serious threats.  相似文献   

Genetic Variation for Heat Tolerance During the Reproductive Phase in Brassica rapa     

Annisa  S. Chen  N. C. Turner  W. A. Cowling 《Journal of Agronomy and Crop Science》2013,199(6):424-435

We investigated heat tolerance at the reproductive stage in six spring‐type B. rapa accessions and one B. juncea accession as a control. Plants were subjected to two temperature treatments for seven days in controlled environmental rooms, beginning one day before the first open flower on the main stem inflorescence. The high‐temperature treatment ranged from 25 °C to 35 °C during 16 h light and 25 °C during 8 h dark. The control temperature treatment was set at 23 °C during 16 h light and 15 °C during 8 h dark. Soil moisture was maintained at close to field capacity to avoid drought stress. Main stem buds that emerged during the treatment period were tagged, and pod and seed production was recorded at each reproductive node. Leaf temperature depression and leaf conductance increased in the high‐temperature treatment which indicated that plants were not drought stressed. A leafy vegetable type of B. rapa from Indonesia was the most tolerant to high temperature, as defined by its ability to set seed equally well in the control and high‐temperature treatments, followed by an oilseed type from Pakistan. Pollen viability remained above 87 % in all accessions and treatments. We conclude that bud number and length, and pod number produced under high temperatures, might provide a useful preliminary screen for high‐temperature tolerance and that B. rapa may be a valuable source of heat tolerance in canola (B. napus).  相似文献   

Pseudohyperparathyroidism in a mare associated with squamous cell carcinoma of the vulva     

L F Karcher  J L Le Net  B F Turner  T J Reimers  B C Tennant 《The Cornell veterinarian》1990,80(2):153-162

An 18-year-old Appaloosa mare was examined because of squamous cell carcinoma of the vulva, anorexia with pronounced weight loss, and hypercalcemia. The tumor had developed rapidly over a period of 3 months and externally extended ventrally involving the perineum and the dorsal aspect of the udder. Necropsy examination demonstrated a large primary squamous cell carcinoma of the vulva, perineum, and mammary gland with metastases to the supramammary, sublumbar, deep inguinal, and mediastinal lymph nodes. No gross renal lesions were observed and, histologically, there was only mild vacuolation of renal tubular epithelium. Based on the normal concentration of serum parathyroid hormone, the absence of evidence of hypervitaminosis D, and normal renal function, a diagnosis was made of hypercalcemia of malignancy or pseudohyperparathyroidism. The mechanism responsible for hypercalcemia was not determined, but the histologic type of the neoplasm and the clinical course suggested possible production of a humoral hypercalcemic factor by the neoplasm, similar to that demonstrated in certain types of human squamous cell carcinoma.  相似文献   

NURSES NEWS: Nurses at Harrogate     

J. Turner 《The Journal of small animal practice》1990,31(7):367-367

  相似文献   

A revised concept of landscape equilibrium: Disturbance and stability on scaled landscapes   总被引：20，自引：0，他引：20  

Monica G. Turner  William H. Romme  Robert H. Gardner  Robert V. O'Neill  Timothy K. Kratz 《Landscape Ecology》1993,8(3):213-227

  相似文献   

Intraperitoneal Insemination in Mammals: A Review     

JL Yaniz  M Lopez-Bejar  P Santolaria  J Rutllant  & F Lopez-Gatius 《Reproduction in domestic animals》2002,37(2):75-80

This review focuses on factors associated with the development of intraperitoneal insemination in mammals. Findings to date indicate that fertility improves as the sperm cell concentration rises, but that the optimal sperm number differs in each species. Sperm washing before intraperitoneal insemination favours fertility. Peritoneal fluid shows a variable effect on spermatozoa, depending on the hormonal status of the female. The optimal time for insemination appears to be just prior to ovulation. The technique may be performed either through the abdominal or the vaginal wall. Verification of sperm deposition in the proximity of the ovaries improves fertility rates. Although associated with some risk of infection and an immune reaction against spermatozoa, the intraperitoneal technique rarely gives rise to severe anaphylactic shock, peritonitis, adhesion formation and the production of anti‐sperm antibodies and these complications may be prevented by adequate sperm pretreatment and antibiotic therapy. The success of intraperitoneal insemination in humans, with results comparable with those of intrauterine insemination in the treatment of infertility, suggest the potential use of this technique in domestic mammals, especially in those in which intrauterine insemination poses practical difficulties. Some of the methods applied in human intraperitoneal insemination, such as confirming the position of the needle in the peritoneal cavity, and sperm pre‐treatments might also improve results in domestic species. Conversely, the use of the animal model should help to develop some aspects of this technique in humans.  相似文献