Siliceous tablets in the larval shells of apatitic discinid brachiopods     

A Williams  M Cusack  JO Buckman  T Stachel 《Science (New York, N.Y.)》1998,279(5359):2094-2096

The marine bivalved Brachiopoda are abundant throughout the geological record and have apatitic (CaPO4-rich) or calcitic (CaCO3-rich) shells. Vesicles covering the larval valves of living apatitic-shelled discinids contain tablets of silica. The tablets are cemented into close-packed mosaics by spherular apatite in glycosaminoglycans. They are usually lost as vesicles degrade but leave imprints on the underlying apatitic shell. Similar imprints ornament larval surfaces of some of the earliest Paleozoic apatitic-shelled brachiopods and may also be indicators of siliceous biomineralization.  相似文献   

Lobster larval transport in the southern Gulf of St. Lawrence     

JOËL CHASSÉ  ROBERT J. MILLER 《Fisheries Oceanography》2010,19(5):319-338

A bio‐physical semi‐Langrangian model was developed to follow the drift and abundance of lobster larvae from hatching to settlement as post‐larvae. The geographic domain encompasses Northumberland Strait and the areas surrounding Prince Edward Island in the southern Gulf of St. Lawrence. The model was run for ten larval seasons, 1983–87 and 1997–2001, representing two periods of egg production. The model was forced with tides, winds, heat fluxes, and marine and freshwater fluxes at open boundaries. Biological inputs were location, date, and density of larvae at hatching, development rates, a time window and a minimum bottom temperature required for successful settlement, and two scenarios of daily mortality. Net drift was west to east but stronger on the north than the south side of Prince Edward Island. The hatch was greater in the second 5‐yr period, but the spatial patterns of settlement were similar. For both mortality scenarios, the same five of the 24 larval source areas were important in providing settlers. Horizontal shear of larval distribution indicates fishing communities were dependent on the hatch from fishing grounds of multiple upstream communities. Variation in daily and annual post‐larval settlement was greatest north of Prince Edward Island. From the 24 source areas there was an eightfold range in the fraction of larvae surviving to settlement, with advection into deep water an important cause of mortality. Four to five possible fishery management areas were identified using multidimensional scaling to group sink areas having shared source areas. We hypothesize leaky discontinuity in connectivity between these groups.  相似文献   

A high‐throughput system used to determine frequency and distribution of phosphine resistance across large geographical regions     

David I Schlipalius  Andrew G Tuck  Hervoika Pavic  Gregory J Daglish  Manoj K Nayak  Paul R Ebert 《Pest management science》2019,75(4):1091-1098

  相似文献   

Adjustment Stresses on Rural Laborers in the Mississippi Delta and the Ozarks     

MARY JO GRINSTEAD-SCHNEIDER  BERNAL L. GREEN 《Growth and change》1978,9(3):36-43

  相似文献   

Cloning of the short-tailed Gyeongju Donggyeong dog via SCNT: conserving phenotypic inheritance     

Yoo Bin CHOI  Geon A KIM  Hyun Ju OH  Min Jung KIM  Young Kwang JO  Erif Maha Nugraha SETYAWAN  Seok Hee LEE  Byeong Chun LEE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):329-331

Somatic cell nuclear transfer is a useful tool to maintain genetic information of animals. The Gyeongju Donggyeong dog is a breed registered as natural monument in Korea. The unique feature of the Donggyeong dog is its tail, as the Donggyeong dog can be classified as either short tailed or tailless. The aim of this study was to preserve the Donggyeong dog’s unique feature by cloning. Fibroblasts were obtained from a short-tailed Donggyeong dog. In vivo matured oocytes were enucleated, microinjected with a donor cell and fused electrically. Reconstructed embryos were transferred to six recipient dogs. One surrogate became pregnant, and one short-tailed Donggyeong dog was delivered. This study demonstrated that the phenotype of the Donggyeong dog could be conserved by somatic cell nuclear transfer.  相似文献   

Correction of sickle cell disease in adult mice by interference with fetal hemoglobin silencing     

Xu J  Peng C  Sankaran VG  Shao Z  Esrick EB  Chong BG  Ippolito GC  Fujiwara Y  Ebert BL  Tucker PW  Orkin SH 《Science (New York, N.Y.)》2011,334(6058):993-996

Persistence of human fetal hemoglobin (HbF, α(2)γ(2)) in adults lessens the severity of sickle cell disease (SCD) and the β-thalassemias. Here, we show that the repressor BCL11A is required in vivo for silencing of γ-globin expression in adult animals, yet dispensable for red cell production. BCL11A serves as a barrier to HbF reactivation by known HbF inducing agents. In a proof-of-principle test of BCL11A as a potential therapeutic target, we demonstrate that inactivation of BCL11A in SCD transgenic mice corrects the hematologic and pathologic defects associated with SCD through high-level pancellular HbF induction. Thus, interference with HbF silencing by manipulation of a single target protein is sufficient to reverse SCD.  相似文献   

Ultrasensitive stain for proteins in polyacrylamide gels shows regional variation in cerebrospinal fluid proteins   总被引：126，自引：0，他引：126  

C R Merril  D Goldman  S A Sedman  M H Ebert 《Science (New York, N.Y.)》1981,211(4489):1437-1438

A new silver stain for electrophoretically separated polypeptides can be rapidly and easily used and can detect as little as 0.01 nanogram of protein per square millimeter. When employed with two-dimensional electrophoresis, it should permit qualitative and quantitative characterization of protein distributions in body fluids and tissues. It has been used to demonstrate regional variations in cerebrospinal fluid proteins.  相似文献   

DNA polymerase activities of human milk   总被引：1，自引：0，他引：1  

B I Gerwin  P S Ebert  H C Chopra  S G Smith  J P Kvedar  S Albert  M J Brennan 《Science (New York, N.Y.)》1973,180(82):198-201

  相似文献   

Einfluss von blattappliziertem Bor auf Boraufnahme und Fruchteigenschaften von Kulturheidelbeeren (Vaccinium corymbosum)     

C. Hahnfeld  Dr. G. Ebert  A. Alexander 《Erwerbs-Obstbau》2004,46(6):129-132

In 2003, highbush blueberry (Vaccinium corymbosum) cultivars ‘Brigitta Blue’ and ‘Nelson’ were treated with a foliar boron-containing, ascofol spray (Wuxal^®). After blossoming, the plants were sprayed three times with 0.5% ascofol solution. Control plants were sprayed with tap water. Fruit harvest of each cultivar was on July 19 and 30, respectively. Leaf samples were taken on June 4 and August 7. The boron content of fruits and leaves was analyzed along with fruit yield and single berry weight. The potential absorption rate of applied boron (boron increase in leaves and fruits) was calculated. Foliarly applied boron was readily taken up by the leaves of both cultivars and translocated to the fruits. A potential boron absorption rate of 2.4% was calculated for ‘Nelson’. Foliar application of boron did not increase fruit yield in either cultivar. However, ‘Nelson’ showed a slight increase of berry weight in the second harvest, associated with the boron treatments.  相似文献   

Dilatation of the Ampullae and an Increased Incidence of Loose Sperm Heads after Bilateral Vesiculectomy in a Bull     

JO Nöthling  DH Volkmann 《Reproduction in domestic animals》1997,32(6):321-324

  相似文献