1,110 research outputs found
The German Bight (North Sea) is a nursery area for both locally and externally produced sprat juveniles
To better understand the role of the German Bight (GB) as a nursery area for juvenile North Sea sprat Sprattus sprattus we sought to determine whether the area may receive only locally or also externally produced offspring. We sampled juveniles during 3 trawl surveys in the GB in August, September, and October 2004 and applied otolith microstructure analysis in order to reconstruct their distributions of the day-of-first-increment-formation (dif). These were contrasted with spatial and seasonal patterns of sprat egg abundance in the GB and its adjacent areas, observed during 6 monthly plankton surveys. It was found that the majority of juveniles originated mainly from April/May 2004, coinciding with high spawning activity west of the GB, whereas spawning and larval production inside the GB peaked notably later, in May/June. This indicated that a large proportion of juveniles was produced outside the GB and transported subsequently into it through passive and/or active migration. Shifts to later mean difs from one survey to the next and length distributions indicative of the simultaneous presence of multiple cohorts, supported the notion that the GB is a complex retention and nursery area for sprat offspring from different North Sea spawning grounds and times. Later born juveniles had significantly faster initial growth rates than earlier born conspecifics, which was likely temperature-mediated, given the strong correlation between back-calculated growth histories and sea surface temperature as a proxy for thermal histories of juveniles (r(2) = 0.52). (C) 2009 Elsevier B.V. All rights reserved
Resolution of a low-lying placenta and placenta previa diagnosed at the midtrimester anatomy scan
Food conversion efficiency and the von Bertalanffy growth function 1: a modification of Pauly's model
A simple modification of Pauly's model for relating food conversion efficiency (K sub(1)) and body weight is proposed. The key parameter is an index to how efficiently food can be absorbed; the other parameter is related to the surface-limiting growth, an important component of von Bertalanff's and Pauly's theories of fish growth
Depth-dependent nutritional condition of sprat Sprattus sprattus larvae in the central Bornholm Basin, Baltic Sea
Bimodal depth distribution patterns observed for sprat Sprattus sprattus larvae in previous field studies conducted in the deep basins of the Baltic Sea have led researchers to hypothesise that larval sprat condition was depth-dependent. We examined this hypothesis by measuring morphological, biochemical and otolith-based proxies for nutritional condition in sprat larvae collected in discrete 5 m depth intervals from the surface to the bottom in the central Bornholm Basin. Similar to earlier studies, larval sprat were most abundant in 2 depth strata (0 to 10 and 65 to 75 m). Their nutritional condition in surface and deep waters was not uniformly expressed by the different indices. For example, sprat larvae from 0 to 10 m could not be distinguished from conspecifics caught at 65 to 75 m by a long-latency condition proxy (otolith-based growth rates). Similarly, a medium-latency proxy (RNA:DNA) did not suggest differences in condition between the depths. However, short-latency proxies (protein:standard length and DNA:dry weight) supported the depth-dependent condition hypothesis. The lack of correspondence and pitfalls associated with the use and interpretation of multiple condition indices (e.g. the influences of temperature and body size) are discussed and recommendations to strengthen these various metrics are provided
Food conversion efficiency and the von Bertalanffy growth function. Part II and conclusion: Extension of the new model to the generalized von Bertalanffy growth function
Food conversion, Growth, Mathematical models
A new Retention Index for the Central Baltic Sea: Long-Term Hydrodynamic Modelling Used to Improve Baltic Sprat, Sprattus sprattus, Recruitment Models
To study inter-annual differences in drift patterns of larval sprat from the Bornholm Basin, we used a 3D, eddy-resolving circulation model of the Baltic Sea and simulated the drift of Lagrangian particles for each of 24 years (1979-2002) of available forcing data. We observed that in some years particles were transported almost completely out of the basin, whereas circulation in other years retained the majority of drifters within the seeding area (Bornholm Basin). A new retention index was derived that is associated to age 0 sprat recruitment in ICES Subdivision 25, estimated from area-disaggregated MSVPA runs. The significant linear relationship (P 80%) than those derived from particles released earlier into the model domain. This intra-annual pattern may suggest that recruitment success in central Baltic sprat was ā at least during the last decade - predominantly determined by the relative survival of larval cohorts emerging late in the spawning season. The index is significantly cross-correlated to other environmental time series, most importantly annual surface temperature in August, which makes it difficult to conclude on the processes crucial for central Baltic sprat recruitment success
Predictive value of midtrimester universal cervical length screening based on parity
OBJECTIVES: To evaluate the effect of parity on performance characteristics of midtrimester cervical length (CL) in predicting spontaneous preterm birth (sPTB) before 37 weeks.
METHODS: This was a retrospective cohort study of 13,508 women with no history of sPTB undergoing universal transvaginal CL screening at 17 to 23 weeks\u27 gestation from 2011 to 2016. Patients who declined screening or with unknown delivery outcomes were excluded. Areas under the receiver operator characteristic curves were used to assess and compare the predictive ability of CL screening for sPTB. The sensitivity, specificity, and positive and negative predictive values were estimated for specific CL cutoffs for prediction of sPTB.
RESULTS: There were 20,100 patients, of whom 2087 (10%) declined screening and 4505 (22%) did not meet inclusion criteria. Of the remaining 13,508 patients, 43% were nulliparous. The incidence rates of sPTB were 6.5% in nulliparas and 4.9% in multiparas (Pā\u3cā.001). The mean CLs were 39.9 mm in nulliparas and 41.8 mm in multiparas (Pā\u3cā.001), and those of the first percentiles were 19.0 mm in nulliparas and 24.0 mm in multiparas. Cervical length was significantly more predictive of sPTB in nulliparas (area under the curve, 0.67; 95% confidence interval, 0.63-0.70; versus 0.61, 95% confidence interval, 0.57-0.63; P = .008). At CL cutoffs of 10, 15, 20, and 25 mm or less, the sensitivity was lower in multiparas, and the specificity was comparable between the groups.
CONCLUSIONS: Midtrimester CL is less predictive of sPTB in multiparas compared to nulliparas. The poor predictive ability, especially in multiparas, calls into question the value of universal CL screening in this population
RGD-avidinābiotin pretargeting to Ī±vĪ²3 integrin enhances the proapoptotic activity of TNFĪ± related apoptosis inducing ligand (TRAIL)
Recombinant TNF-related apoptosis-inducing ligand (TRAIL) is considered a powerful and selective inducer of tumor cell death. We hypothesize that TRAILās potential as anticancer agent can be enhanced further by promoting its accumulation in tumor tissue. For this purpose, we developed TRAIL complexes that bind to angiogenic endothelial cells. We employed an avidinābiotin pretargeting approach, in which biotinylated TRAIL interacted with RGD-equipped avidin. The assembled complexes killed tumor cells (Jurkat T cells) via apoptosis induction. Furthermore, we demonstrated that the association of the RGD-avidin-TRAIL complex onto endothelial cells enhanced the tumor cell killing activity. Endothelial cells were not killed by TRAIL nor its derived complexes. Our approach can facilitate the enrichment of TRAIL onto angiogenic blood vessels, which may enhance intratumoral accumulation. Furthermore, it offers a versatile technology for the complexation of targeting ligands with therapeutic recombinant proteins and by this a novel way to enhance their specificity and activity
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