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41.
42.
Ewa Tomaszewska Siemowit Muszyski Piotr Dobrowolski Dariusz Wicek Agnieszka Tomczyk‐Warunek Izabela
wietlicka Stefan G. Pierzynowski 《Journal of animal physiology and animal nutrition》2019,103(2):626-643
It has been demonstrated in animal studies that prenatal administration of β‐hydroxy‐β‐methylbutyrate (HMB, metabolite of leucine) influences general growth and mechanical endurance of long bones in newborn offspring in sex‐dependent manner. The present experiment was conducted to evaluate the effect of HMB treatment of pregnant sows on bone development in offspring at weaning. From 70th day until the 90th day of gestation, sows received either a basal diet (n = 12) or the same diet supplemented with HMB (n = 12) at the dose of 0.2 g/kg of body weight/day. Femora obtained from six males and females in each group weaned at the age of 35 days were examined. Maternal HMB treatment significantly enhanced body weight and changed bone morphology increasing femur mechanical strength in both sexes. Maternal HMB supplementation also elevated bone micro‐ and macroelement concentrations and enhanced content of proteoglycans in articular cartilage. Based on the obtained results, it can be concluded that maternal HMB supplementation in the mid‐gestation period significantly accelerated bone development in both sexes by upregulation of a multifactorial system including leptin and osteoprotegerin. However, the sex (irrespective of the HMB treatment) was the factor which influenced the collagen structure in cartilages and trabecular bone, as demonstrated both by the Picrosirius red staining and performed analysis of thermal stability of collagenous tissues. The structural differences in collagen between males and females were presumably related to a different collagen maturity. No studies conducted so far provided a detailed morphological analysis of bone, articular cartilage, growth plate and the activities of the somatotropic and pituitary–gonadal axes, as well as leptin/osteoprotegerin system in weaned offspring prenatally treated with HMB. This study showed also the relationship between the maternal HMB treatment and bone osteometric and mechanical traits, hormones, and growth and bone turnover markers such as leptin, osteoprotegerin and insulin‐like growth factor‐1. 相似文献
43.
The morphology of parcel patterns created by humans both in urban and rural areas is investigated. The parcel size distribution
function, f(a), provides a criterion, that enables unambiguous classification of each piece of land as city core, suburbs, or rural area.
The morphology of the rural area corresponds to a scale-free structure and follows a power-law distribution f(a) ~ a
−n
of the parcel areas with the exponent n ≈ 1. In suburbs, the area distribution follows the log-normal distribution. In the city core, f(a) has an unimodal shape with an algebraically decaying tail, n = 2. Our study is based on data originating mainly from North America, the Hawaiian Islands, and Australia. For the regions
analyzed, the characteristics of the parcel size distribution are universal and robust with respect to geographical, historical,
and economical conditions accompanying development of a given area. The urbanization process can be described in terms of
the changes of the morphology of the patterns of land fragmentation. In this formulation, the rural morphology, which can
be thought as natural one because it exhibits a scale-free distribution of parcel sizes, is transformed into the artificial
morphology developed in the city centers.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
44.
Popmintchev T Chen MC Popmintchev D Arpin P Brown S Alisauskas S Andriukaitis G Balciunas T Mücke OD Pugzlys A Baltuska A Shim B Schrauth SE Gaeta A Hernández-García C Plaja L Becker A Jaron-Becker A Murnane MM Kapteyn HC 《Science (New York, N.Y.)》2012,336(6086):1287-1291
High-harmonic generation (HHG) traditionally combines ~100 near-infrared laser photons to generate bright, phase-matched, extreme ultraviolet beams when the emission from many atoms adds constructively. Here, we show that by guiding a mid-infrared femtosecond laser in a high-pressure gas, ultrahigh harmonics can be generated, up to orders greater than 5000, that emerge as a bright supercontinuum that spans the entire electromagnetic spectrum from the ultraviolet to more than 1.6 kilo-electron volts, allowing, in principle, the generation of pulses as short as 2.5 attoseconds. The multiatmosphere gas pressures required for bright, phase-matched emission also support laser beam self-confinement, further enhancing the x-ray yield. Finally, the x-ray beam exhibits high spatial coherence, even though at high gas density the recolliding electrons responsible for HHG encounter other atoms during the emission process. 相似文献
45.
Bhowmick NA Chytil A Plieth D Gorska AE Dumont N Shappell S Washington MK Neilson EG Moses HL 《Science (New York, N.Y.)》2004,303(5659):848-851
Stromal cells can have a significant impact on the carcinogenic process in adjacent epithelia. The role of transforming growth factor-beta (TGF-beta) signaling in such epithelial-mesenchymal interactions was determined by conditional inactivation of the TGF-beta type II receptor gene in mouse fibroblasts (Tgfbr2fspKO). The loss of TGF-beta responsiveness in fibroblasts resulted in intraepithelial neoplasia in prostate and invasive squamous cell carcinoma of the forestomach, both associated with an increased abundance of stromal cells. Activation of paracrine hepatocyte growth factor (HGF) signaling was identified as one possible mechanism for stimulation of epithelial proliferation. Thus, TGF-beta signaling in fibroblasts modulates the growth and oncogenic potential of adjacent epithelia in selected tissues. 相似文献
46.
Kita A Bråthen E Knutsen SH Wicklund T 《Journal of agricultural and food chemistry》2004,52(23):7011-7016
The aim of this work was to examine the effect of blanching or soaking in different acid solutions on the acrylamide content in potato crisps. Furthermore, the effects of a shorter frying time and a lower frying temperature combined with a postdrying were investigated. Soaking or blanching of potato slices in acidic solutions decreased the pH of potato juice and increased the extraction of amino acids and sugars. Potato crisps obtained after such pretreatments were characterized by lower acrylamide content. The most effective extraction of free amino acids and sugars as well as the largest decrease of acrylamide content (90%) in crisps was obtained when potato slices were soaked in acetic acid solution for 60 min at 20 degrees C. Shorter frying time followed by postdrying resulted in low-moisture potato crisps. Furthermore, the postdrying treatment gave a decreases in acrylamide content of approximately 70% when potato slices were fried at 185 degrees C and approximately 80% when potato slices were fried at 160 degrees C. Effective ways of decreasing acrylamide content in crisps production have been found. Crisps with low acrylamide content and good sensory quality can be obtained either by blanching in acetic acid as pretreatment or by a short frying followed by postdrying. 相似文献
47.
Assessment of the impact of climate change on the latency period of leaf rust on triticale in Poland
Andrzej Wójtowicz Marek Wójtowicz Roland Sigvald Bartosz Czernecki Henryk Ratajkiewicz Agnieszka Łacka 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2020,70(3):195-207
ABSTRACTDisease development in plants is strongly dependent on weather conditions, with temperature playing a particularly significant role by influencing latency period duration. Using two models describing the relationship between latency period and temperature, we performed simulations aimed at predicting changes in the latency period of leaf rust (Puccina recondita f. sp. tritici) on triticale in response to expected climate change. The simulations were based on meteorological data recorded in the period 1986–2005 at locations representing 16 provinces in Poland and based on values obtained after transformation of the observed data to reflect temperature changes under four scenarios (RCP2.6, RCP4.5, RCP6.0 and RCP8.5) according to the giss_e2_r climate model. In all scenarios, the results for the two triticale cultivars studied, Witon (vulnerable to P. recondita) and Gniewko (less susceptible), showed a threat of faster development (shorter leaf rust latency period) on triticale triggered by climate change in south-east and south-central Poland than in other regions. The results also showed an increased probability of future regional diversification of leaf rust latency period duration on vulnerable triticale cultivars, opportunities for earlier start of leaf rust epidemics on triticale in Poland and an increase in ?nal disease severity in comparison with 1986–2005. 相似文献
48.
Janusz A Capone DL Puglisi CJ Perkins MV Elsey GM Sefton MA 《Journal of agricultural and food chemistry》2003,51(26):7759-7763
(E)-1-(2,3,6-Trimethylphenyl)buta-1,3-diene (TPB) was identified as a potent odorant in acid hydrolysates of crude glycoconjugate fractions isolated from grapes and grape vine leaves. TPB was also identified in a Semillon wine, using gas chromatography/mass spectrometry, by co-injection with an authentic sample. TPB had an aroma detection threshold of 40 ng/L in a neutral white wine and the concentration of TPB in four out of five white wines analyzed ranged from 50 to 210 ng/L. 相似文献
49.
In this study, Tulipa fosteriana was found to contain 45S rDNA repeat units of 9.7 and 9.5 kb, in which at least 7 types of 45S rDNAs were identified by restriction
site analysis. For 5S rDNA, repeat units ranging from 364 bp to 396 bp were identified. The diploid cultivars (2n = 2x = 24)
‘Christmas Dream’ and ‘Queen of Night,’ representing the horticultural group T. gesneriana, and ‘Red Emperor’, belonging to T. fosteriana, were compared cytogenetically using cloned 5S and 45S rDNAs. Fluorescence in situ hybridization (FISH) analysis identified
many rDNA sites located on each chromosome in the diploid genomes. For example, we identified 71 sites of 5S rDNA and 10 sites
of 45S rDNA in ‘Red Emperor’. Additionally, FISH analyses enabled construction of karyotypes for these cultivars. Karyotype
comparison of T. gesneriana cultivars showed conservation of repetitive rDNA unit positioning. A clear difference in chromosome size and signal pattern
was observed between T.
gesneriana and T.
fosteriana cultivars. Here we demonstrate the unique nature of the highly repeated 5S rDNA units in these Tulipa species and the usefulness of FISH karyotyping with cloned 5S and 45S rDNAs to clearly distinguish between chromosomes from
T. gesneriana and T. fosteriana.
Hitoshi Mizuochi and Agnieszka Marasek contributed equally to this paper 相似文献
50.
Agnieszka Nowak Joanna Kochan Ewa Świętek Barbara Kij Sylwia Prochowska Wojciech Witarski Monika Bugno-Poniewierska Wojciech Niżański 《Reproduction in domestic animals》2020,55(8):992-997
The aim of this study was to evaluate the applicability of the Cryotech technique for the vitrification of domestic cat (Felis catus) oocytes, as a model for other feline species threatened with extinction. This technique, in which oocytes are stored in a minimal volume of medium, is already widely used in human assisted reproductive technology. In the first part of this study, a viability test (EtBr/FDA) was used to evaluate the toxicity of the vitrification media (solutions). After IVM, oocytes were placed in vitrification and warming solutions according to the manufacturer's procedure, with or without exposure to liquid nitrogen. The solutions and the vitrification procedure each caused a reduction in oocyte viability, with survival rates of 71.4% in oocytes exposed to the Cryotech media (without cooling in liquid nitrogen), and 62% in oocytes that were vitrified. In the second part of the experiment, parthenogenetic activation was used to evaluate the developmental potential of oocytes previously vitrified using the Cryotech method. After warming, the oocytes were activated using a combination of 0.7 µM ionomycin in TCM 199 medium (5 min) followed by 2 mM 6-DMAP in TCM 199 supplemented with 10% FBS (3 hr), then cultured and evaluated every 24 hr for parthenogenetic cleavage. In the experimental group, 23/50 (46%) cleaved embryos were obtained. Domestic cat oocytes, vitrified by the Cryotech method, are characterized by high survival rates. However, it is necessary to improve the technique to increase the developmental competence of embryos obtained from vitrified oocytes. 相似文献