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排序方式: 共有351条查询结果,搜索用时 31 毫秒
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Li Day Mi Xu Sofia K. Øiseth Yacine Hemar Leif Lundin 《Food and Bioprocess Technology》2010,3(6):928-934
A range of thermal and mechanical processes were used to create dispersions with different particle morphologies, i.e., systems that contain primarily plant cell wall clusters with an average particle size (d(0.5)) of ~200 µm, single cells ((d(0.5)?=?~70 µm) or cell fragments (d(0.5)?=?~40 µm). The small and large deformation rheology (viscoelastic properties and flow properties) of these dispersions, with a range of total solid contents covering textures varying from a fluid to a paste, were determined. The particle dispersions showed weak gel-like behaviour. Their elastic modulus (G′) as a function of total solid content exhibited three regions of different rheological behaviours. The particles formed particulate colloidal networks at relatively low solid content. The interaction of particles contributed to the sharp increase in the elastic modulus of the dispersion in the concentrated region. Further packing of particles beyond the critical packing volume fraction, caused the G′ for the ‘cluster-cell’ and the ‘single-cell’ dispersions to reach a plateau value. This is due to particle deformation resulting in changes in their microstructure and their ability to pack closely. Plant particle dispersions displayed abrupt yielding at the critical stress with a 3–4 order decrease in viscosity and high yield stress at low solids due to the formation of particulate colloidal network. 相似文献
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Stahl A Schellewald C Stavdahl ? Aamo OM Adde L Kirker?d H 《IEEE transactions on neural systems and rehabilitation engineering》2012,20(4):605-614
Cerebral palsy (CP) is a perinatally acquired nonprogressive brain damage resulting in motor impairment affecting mobility and posture. Early identification of infants with CP is desired to target early interventions and follow-up. During early infancy, distinct motion patterns occur which are highly predictive for later disability. These motor patterns can be observed and recorded. In this paper, a method to predict later CP based on early video recordings of the infants' spontaneous movements, applying optical flow and statistical pattern recognition, is presented. We extract motion information from video recordings of young infants using a total variation related optical flow method. By using wavelet analysis features from motion trajectories of points initiated on a regular grid were extracted and classified using a support vector machine. 相似文献
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Mette Kristensen Lars F Østergaard Ulrich Halekoh Henry Jørgensen Charlotte Lauridsen Kirsten Brandt Susanne Bügel 《Journal of the science of food and agriculture》2008,88(12):2161-2172
BACKGROUND: Many consumers perceive organic foods as more nutritious than conventional foods. However, the existing evidence is insufficient to support or refute this belief. The purpose of the present study was to investigate the effect of three different model cultivation systems on selected major and trace element contents of dried foodstuffs (carrots, kale, peas, potatoes and apples) grown in two consecutive years, as well as mineral retention determined in 36 rats (second generation in a multi‐generation study) fed diets based on these foodstuffs from one year. RESULTS: Overall, there was no evident trend towards differences in element content of foodstuffs or diets due to the use of different cultivation systems, and differences between harvest years exceeded those seen between cultivation methods. Also, no significant differences in the retention of elements in rats fed diets derived from different cultivation systems were seen, since higher intake resulted in correspondingly higher excretion. CONCLUSION: This study does not support the belief that organically grown foodstuffs generally contain more major and trace elements than conventionally grown foodstuffs, nor does there appear to be an effect on the bioavailability of major and trace minerals in rats. Copyright © 2008 Society of Chemical Industry 相似文献
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Vilde Yuli Stenberg Roy Hartvig Larsen Li-Wei Ma Qian Peng Petras Juzenas
yvind Sverre Bruland Asta Juzeniene 《International journal of molecular sciences》2021,22(9)
Radioligand therapy targeting the prostate-specific membrane antigen (PSMA) is rapidly evolving as a promising treatment for metastatic castration-resistant prostate cancer. The PSMA-targeting ligand p-SCN-Bn-TCMC-PSMA (NG001) labelled with 212Pb efficiently targets PSMA-positive cells in vitro and in vivo. The aim of this preclinical study was to evaluate the therapeutic potential of 212Pb-NG001 in multicellular tumour spheroid and mouse models of prostate cancer. The cytotoxic effect of 212Pb-NG001 was tested in human prostate C4-2 spheroids. Biodistribution at various time points and therapeutic effects of different activities of the radioligand were investigated in male athymic nude mice bearing C4-2 tumours, while long-term toxicity was studied in immunocompetent BALB/c mice. The radioligand induced a selective cytotoxic effect in spheroids at activity concentrations of 3–10 kBq/mL. In mice, the radioligand accumulated rapidly in tumours and was retained over 24 h, while it rapidly cleared from nontargeted tissues. Treatment with 0.25, 0.30 or 0.40 MBq of 212Pb-NG001 significantly inhibited tumour growth and improved median survival with therapeutic indexes of 1.5, 2.3 and 2.7, respectively. In BALB/c mice, no signs of long-term radiation toxicity were observed at activities of 0.05 and 0.33 MBq. The obtained results warrant clinical studies to evaluate the biodistribution, therapeutic efficacy and toxicity of 212Pb-NG001. 相似文献
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Biotic and abiotic determinants of the ascent behaviour of adult Atlantic salmon transiting passable waterfalls
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Robert J. Lennox Eva B. Thorstad Ola H. Diserud Finn Økland Steven J. Cooke Ingar Aasestad Torbjørn Forseth 《河流研究与利用》2018,34(8):907-917
The spawning migration of Atlantic salmon has been characterized by tracking salmon carrying electronic tags as they ascend rivers, but still little is known about how natural obstacles such as waterfalls influence migratory behaviour and how such behaviours are mediated by various biotic (e.g., fish size) and abiotic (e.g., discharge, water temperature, and barometric pressure) factors. The Norwegian river Numedalslågen is interrupted by natural waterfalls ranging in height from 2 to 6 m. We tagged 113 Atlantic salmon with radio transmitters in the estuary and used stationary radio telemetry stations to track fish. Ninety‐one salmon were recorded in Numedalslågen, 39 of which remained in the river for spawning. Large salmon moved farther and faster upriver but also delayed longer and had lower daily probability to pass the second waterfall. Delay below and passage probability at the final, largest waterfall was affected by water discharge, wherein passage occurred when discharge was declining. Barometric pressure also influenced daily probability of ascent, albeit in opposite directions for each waterfall. Importantly, we also found that salmon with surgically implanted radio transmitters moved farther upriver on average and delayed less time below one of the waterfalls than those with externally attached transmitters. Although there is variance in timing arising from individual decision‐making, we showed that natural waterfalls delay progress of Atlantic salmon on their spawning migration and that both biotic (i.e., size) and abiotic (i.e., barometric pressure and discharge) factors influenced the salmon's decisions to pass waterfalls that they encounter. 相似文献
60.
Candida cylindracea lipase (SIGMA) was tested against triglycerides (TG) and wax esters (WE) of marine origin as substrates. Under the same conditions, wax esters were hydrolysed at a lower rate than the triglycerides. The C14 to C18 saturated and monounsaturated fatty acids were preferentially hydrolysed whereas the longer chain monoenes (20:1 and 22:1) and particularly the polyunsaturated fatty acids (18:4,20:5 and 22:6) were resistant to the hydrolysis in triglycerides as well as in wax esters. No specificity was demonstrated for the fatty alcohols in the wax esters. 相似文献