Is manual foot lenght measurement of comparable value to ultrasound femur and humerus measurement in anatomical studies for the assessment of foetal age?

Contemporary anatomical studies require reliable methods for determining foetal age. Menstrual age is often found to be inadequate. A combination of several anatomical features showing age-dependency may result both in exact age approximation and pathology detection. The authors compared the manual foot length measurements with the ultrasound femur and humerus length measurements of aborted foetuses in the calculation of foetal age. The correlation between femur length and foot length as well as humerus length and foot length were statistically significant. The expected value formulae for foot length are presented. The authors conclude that foetal age assessment based on foot length metering is reliable before the 7th calendar month of pregnancy and correlates with ultrasound measurements of the humerus and femur

Relationships between the El-Niño Southern Oscillation and spate flows in southern Africa and Australia

International audienceThe flow records of arid zone rivers are characterised by a high degree of seasonal variability, being dominated by long periods of very low or zero flow. Discrete flow events in these rivers are influenced by aseasonal factors such as global climate forcings. The atmospheric circulations of the El-Niño Southern Oscillation (ENSO) have been shown to influence climate regimes across many parts of the world. Strong teleconnections between changing ENSO regimes and discharges are likely to be observed in highly variable arid zones. In this paper, the influence of ENSO mechanisms on the flow records of two arid zone rivers in each of Australia and Southern Africa are identified. ENSO signals, together with multi-decadal variability in their impact as identified through seasonal values of the Interdecadal Pacific Oscillation (IPO) index, are shown to influence both the rate of occurrence and the size of discrete flow episodes in these rivers. Keywords: arid zones, streamflow, spates, climate variability, ENSO, Interdecadal Pacific Oscillation, IP

Characterization of multiple stable conformers of the EC5 domain of E-cadherin and the interaction of EC5 with E-cadherin peptides

The objectives of this work were to express the EC5 domain of E-cadherin and determine its structural characteristics as well as to evaluate the binding properties of HAV and BLG4 peptides to EC5 using spectroscopic methods. Homophilic interactions of E-cadherins are responsible for cell-cell adhesion in the adherens junctions of the biological barriers (i.e., intestinal mucosa and blood-brain barriers). The EC5 domain of E-cadherin has an important role in T-cell adhesion to intestinal mucosa via αEβ7 integrin-E-cadherin interactions. In this study, the expressed EC5 has a high thermal stability (Tm = 64.3 °C); it also has two stable conformations at room temperature, which convert to one conformation at approximately 54.5 °C. NMR and FTIR showed that HAV and BLG4 peptides bind to EC5. HSQC-NMR showed that either Asn or Gln of EC5 was involved in the interactions with HAV and BLG4 peptides. EC5 underwent a conformational change upon interaction with the HAV and BLG4 peptides. Finally, the binding properties of both peptides were modeled by docking experiments, and the results suggest that Asn-46 and Asn-75 of EC5 could be involved during the interaction with the peptides and that the Ser and Trp residues of the HAV and BLG4 peptides, respectively, were important for binding to EC5

Dynamic elements and kinetics: Most favorable conformations of peptides in solution with measurements and simulations

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared inJ. Chem. Phys. 151, 225102 (2019); doi: 10.1063/1.5131782 and may be found at https://aip.scitation.org/doi/10.1063/1.5131782.Small peptides in solution adopt a specific morphology as they function. It is of fundamental interest to examine the structural properties of these small biomolecules in solution and observe how they transition from one conformation to another and form functional structures. In this study, we have examined the structural properties of a simple dipeptide and a five-residue peptide with the application of far-UV circular dichroism (CD) spectroscopy as a function of temperature, fluorescence anisotropy, and all-atom molecular dynamics simulation. Analysis of the temperature dependent CD spectra shows that the simplest dipeptide N-acetyl-tryptophan-amide (NATA) adopts helical, beta sheet, and random coil conformations. At room temperature, NATA is found to have 5% alpha-helical, 37% beta sheet, and 58% random coil conformations. To our knowledge, this type of structural content in a simplest dipeptide has not been observed earlier. The pentapeptide (WK5) is found to have four major secondary structural elements with 8% 310 helix, 14% poly-L-proline II, 8% beta sheet, and 14% turns. A 56% unordered structural population is also present for WK5. The presence of a significant population of 310 helix in a simple pentapeptide is rarely observed. Fluorescence anisotropy decay (FAD) measurements yielded reorientation times of 45 ps for NATA and 120 ps for WK5. The fluorescence anisotropy decay measurements reveal the size differences between the two peptides, NATA and WK5, with possible contributions from differences in shape, interactions with the environment, and conformational dynamics. All-atom molecular dynamics simulations were used to model the structures and motions of these two systems in solution. The predicted structures sampled by both peptides qualitatively agree with the experimental findings. Kinetic modeling with optimal dimensionality reduction suggests that the slowest dynamic processes in the dipeptide involve sidechain transitions occurring on a 1 ns timescale. The kinetics in the pentapeptide monitors the formation of a distorted helical structure from an extended conformation on a timescale of 10 ns. Modeling of the fluorescence anisotropy decay is found to be in good agreement with the measured data and correlates with the main contributions of the measured reorientation times to individual conformers, which we define as dynamic elements. In NATA, the FAD can be well represented as a sum of contributions from representative conformers. This is not the case in WK5, where our analysis suggests the existence of coupling between conformational dynamics and global tumbling. The current study involving detailed experimental measurements and atomically detailed modeling reveals the existence of specific secondary structural elements and novel dynamical features even in the simplest peptide systems

Why not "do simple things in a simple way": Use of the Pap test as the first step in screening genetic stability for human cultured stem cell therapy?

The aim of this study was to analyze adipose tissue-derived mesenchymal stem cells (AT-MSCs) using the Pap test as a first screening step to evaluate genetic stability. Human adipose tissue from six healthy female donors was obtained from elective liposuction procedures. The cells were isolated, cultivated at P2/P3, characterized by flow cytometric analysis, and differentiation induced. The AT-MSCs were stained by Papanicolaou staining and analyzed according to the Bethesda classification, and viability-apoptosis relationships were evaluated. The results of the Pap test for Sample I indicated high-grade alterations consistent with genetic instability; for Samples II-V, atypical cells of undetermined significance; and for Sample VI, normal cells. These results demonstrate the potential of using the Pap test as an initial screening step to evaluate the genetic stability of cultured AT-MSCs and also suggest its use for other adherent cells such as embryonic stem cells or induced pluripotent stem cells

Probabilistic streamflow prediction and uncertainty estimation in ephemeral catchments

Conference theme 'Digital Water.'Probabilistic streamflow predictions at the daily scale are of major practical interest for environmental management and planning, including risk assessment as part of reservoir management operations. Ephemeral catchments, where streamflow is frequently zero or negligible, pose particularly stark challenges in this context, due to asymmetry of the error distribution and the discrete (rather than continuous) nature of zero flows. In this work, our focus is on two practical error modelling approaches where predictive uncertainty is approximated by a (transformed) Gaussian error model. The first approach, termed "pragmatic", does not distinguish between zero and positive flows during calibration, but sets negative flows to zero when making predictions. The second approach, termed "explicit", applies a "censored" Gaussian assumption in both calibration and prediction. We report a comparison of these two approaches over 74 Australian catchments with diverse hydroclimatology, using multiple performance metrics. The performance of the approaches depended on the catchment type as follows: (1) "mid-ephemeral" catchments, where 5-50% of days have zero flows, are best modelled using the "explicit" approach in combination with the Box-Cox streamflow transformation with a power parameter of 0.2; (2) "low-ephemeral" catchments, with fewer than 5% zero flow days, can be modelled using the pragmatic approach with (relatively) little loss of predictive performance; (3) "high-ephemeral" catchments, with more than 50% zero flow days, prove challenging to both approaches, and require more specialised techniques. The findings provide practical guidance towards improving probabilistic streamflow predictions in ephemeral catchments. Previous chapter Next chapterDmitri Kavetski, David McInerney, Mark Thyer, Julien Lerat and George Kuczer

An efficient causative event-based approach for deriving the annual flood frequency distribution

In ungauged catchments or catchments without sufficient streamflow data, derived flood frequency methods are often applied to provide the basis for flood risk assessment. The most commonly used event-based methods, such as design storm and joint probability approaches are able to give fast estimation, but can also lead to prediction bias and uncertainties due to the limitations of inherent assumptions and difficulties in obtaining input information (rainfall and catchment wetness) related to events that cause extreme floods. An alternative method is a long continuous simulation which produces more accurate predictions, but at the cost of massive computational time. In this study a hybrid method was developed to make the best use of both event-based and continuous approaches. The method uses a short continuous simulation to provide inputs for a rainfall-runoff model running in an event-based fashion. The total probability theorem is then combined with the peak over threshold method to estimate annual flood distribution. A synthetic case study demonstrates the efficacy of this procedure compared with existing methods of estimating annual flood distribution. The main advantage of the hybrid method is that it provides estimates of the flood frequency distribution with an accuracy similar to the continuous simulation approach, but with dramatically reduced computation time. This paper presents the method at the proof-of-concept stage of development and future work is required to extend the method to more realistic catchments. © 2014 Elsevier B.V.Jing Li, Mark Thyer, Martin Lambert, George Kuczera, Andrew Metcalf

Development of operating rules for a complex multireservoir system by coupling genetic algorithms and network optimization

This is an Accepted Manuscript of an article published in Hydrological Sciences Journal on MAY 1 2013, available online: http://dx.doi.org/10.1080/02626667.2013.779777[EN] An alternative procedure for assessment of reservoir Operation Rules (ORs) under drought situations is proposed. The definition of ORs for multi-reservoir water resources systems (WRSs) is a topic that has been widely studied by means of optimization and simulation techniques. A traditional approach is to link optimization methods with simulation models. Thus the objective here is to obtain drought ORs for a real and complex WRS: the Júcar River basin in Spain, in which one of the main issues is the resource allocation among agricultural demands in periods of drought. To deal with this problem, a method based on the combined use of genetic algorithms (GA) and network flow optimization (NFO) is presented. The GA used was PIKAIA, which has previously been used in other water resources related fields. This algorithm was linked to the SIMGES simulation model, a part of the AQUATOOL decision support system (DSS). Several tests were developed for defining the parameters of the GA. The optimization of various ORs was analysed with the objective of minimizing short-term and long-term water deficits. The results show that simple ORs produce similar results to more sophisticated ones. The usefulness of this approach in the assessment of ORs for complex multi-reservoir systems is demonstrated.The authors wish to thank the Confederacion Hidrogrofica del Jucar (Spanish Ministry of the Environment) for the data provided in developing this study and the Comision Interministerial de Ciencia y Tecnologia, CICYT (Spanish Ministry of Science and Innovation) for funding the projects INTEGRAME (contract CGL2009-11798) and SCARCE (programme Consolider-Ingenio 2010, project CSD2009-00065). The authors also thank the European Commission (Directorate-General for Research and Innovation) for funding the project DROUGHT-R&SPI (programme FP7-ENV-2011, project 282769) and the Seventh Framework Programme of the European Commission for funding the project SIRIUS (FP7-SPACE-2010-1, project 262902). We are grateful to the reviewers for their valuable comments, which have improved this paper.Lerma Elvira, N.; Paredes Arquiola, J.; Andreu Álvarez, J.; Solera Solera, A. (2013). Development of operating rules for a complex multireservoir system by coupling genetic algorithms and network optimization. Hydrological Sciences Journal. 58(4):797-812. https://doi.org/10.1080/02626667.2013.779777S79781258