Effect of molecular weight on the ability of guar gum to enhance "weak gel" rheology of microdispersed oxidised cellulose (MDOC)

MDOC comprises small, essentially insoluble, particles which associate to form “weak gel” networks at concentrations above ∼4 wt%. Association is promoted by guar gum, causing an increase in G′ at low levels of addition and a decrease at higher concentrations, due to excessive aggregation of the MDOC particles. For guar gum samples with molecular weights ranging from ∼60 to ∼1800 kDa, we found that the concentration required to give maximum G′ for 5 wt% dispersions of MDOC increased systematically from ∼0.005 wt% for the lowest molecular weight to ∼0.3 wt% for the highest. We propose that guar gum drives self-association of MDOC to reduce enthalpically-unfavourable (segregative) interactions between the two materials, and that large coils are less effective than smaller ones because a higher proportion of chain sequences are buried in the interior of the coil, where they cannot make segmental contacts with the MDOC particles

IPv6 Applicability in SCADA System Network

     The trend today is to build a secure fault tolerant Internet/Intranet connected distributed SCADA system networks using open and standard software/hardware. This paper made use of advances in Ethernet such as Fast/Gigabit Ethernet, micro-segmentation and full-duplex operation using switches, IPv6 enhanced features and TCP/IP to fulfill the real-time requirements for SCADA system network. OPNET Modeler simulator is used for modeling and simulating the network. The various measured delays showed that IPv6 introduction in such network introduces very small (negligible) delay and shows better performance on applying Quality of Service relative to IPv4. Also it is found that delays increase with increased transported packet size

Industrial Ethernet Protocols IPv6 enabling approach

The current Internet Protocol (IPv4) made Ethernet with TCP/IP find application in industrial automation environment via Industrial Ethernet Protocols. The question "Can things go smooth in Internet Protocol next generation (IPv6)?". This paper answers the question by proposing solutions and proofing via simulation using OPNET Modeler simulator that IPv6 introduction in industrial automation environment introduces very small (negligible) delay relative to IPv4. Measured delays include: global Ethernet delay, IP node end-to-end delay and delay variation for 72, 520 and 1500 bytes transported packet size. Results showed that IPv6 introduces very small delay relative to IPv4, the various delays increase with increased packet size and IPv6 can be used in industrial automation environment. &nbsp

Postpartum depression in the Occupied Palestinian Territory:a longitudinal study in Bethlehem

BACKGROUND: Postpartum depression (PPD) affects women from different cultures around the world. No previous studies have investigated PPD among women in Palestine. Fertility rates in Palestine are among the highest in the world, hence even low rates of PPD could have considerable national impact. The aim of this study was to determine the prevalence of, and risk factors for, PPD among Palestinian mothers. METHODS: 101 mothers were recruited during the registration of their child’s birth (within 1 week) at the Bethlehem branch of the Ministry of Interior. Participants were assessed via a face to face interview, and were followed up 1 week, 2 weeks, 6 weeks, 3 months, and 6 months later by telephone interview. Interviews included the Arabic Edinburgh Postnatal Depression Scale (EPDS), with PPD indicated by depressive symptoms (EPDS score ≥11) at ≥2 follow-up time points. Pearson’s correlation was calculated between repeated EPDS scores, and multivariable logistic regression was used to investigate risk factors for PPD. RESULTS: The prevalence of depressive symptoms was fairly constant (14–19%) over the follow-up period. Most depressive symptoms developed within 1 month of delivery; mothers with depressive symptoms at 3 months postpartum were highly likely to still have symptoms at 6 months. 27.7% (28/101) of women met our criteria for PPD. High parity (odds ratio (OR) 4.52 (95% CI 0.90, 22.8) parity 3+ versus primiparous), unplanned pregnancy (OR 2.44 (0.99, 6.01)) and sex of child not being the one desired (OR 5.07 (1.12, 22.9)) were associated with PPD, but these associations were attenuated in multivariable analysis. CONCLUSIONS: The prevalence of PPD in Palestine appears to be higher than in high income countries, but similar to the prevalence in other Middle Eastern countries. High parity and unplanned pregnancy were identified as risk factors for PPD, suggesting that fully meeting the need for family planning could reduce the incidence of PPD in the Palestinian population

Similarity in depressive symptom profile in a population-based study of migrants in the Netherlands

Objective Depression is a clinical syndrome developed in Western Europe and North-America. The expression of symptoms and the impact of symptoms on functioning may therefore be expected to vary across cultures and languages. Our first aim was to study differences in depressive symptom profile between indigenous and non-Western immigrant populations in the Netherlands. We hypothesized that differences in expression of depressive symptoms would be more likely in the domains of mood and cognitions, and less likely in the domains of psychomotor and vegetative symptoms. Our second aim was to study ethnic differences in the association of depressive symptoms and general functioning. Method In a random community sample stratified for ethnicity in Amsterdam, the Netherlands, depressive symptoms were assessed by bilingual interviewers using the Composite International Diagnostic Interview (CIDI 2.1) and the Symptom Checklist-90-Revised (SCL-90-R). Impairments in functioning were measured by the World Health Organization Disability Assessment Schedule II (WHODAS II). Results were obtained from 812 subjects: N = 321 native Dutch, N = 213 Turkish-Dutch, N = 191 Moroccan-Dutch, N = 87 Surinamese-Dutch. Differences in depressive symptom expression were tested by differential item functioning. Results The prevalence of DSM-IV depressive disorder and the overall level of depressive symptoms were higher in the Turkish and Moroccan immigrant groups compared to native Dutch subjects. Ethnic differences in item functioning of depressive symptoms were rare, and equally unlikely in all four symptom domains. Depression was equally associated with functional impairment across ethnic groups. Conclusion Although depressive symptoms were more common among migrants than in the indigenous population, both the depressive symptom profile and the associated functional impairments were comparable. These findings may help diminishing concerns about the validity of using existing diagnostic procedures among ethnic minority groups

Gelation of high methoxy pectin by acidification with D-glucono-delta-lactone (GDL) at room temperature

Rheological comparisons have been made between preparations of high methoxy pectin (DE approximate to 70%) gelled by acidification with D-glucono-delta-lactone (GDL) on holding for 16 h at 25 degrees C in the presence of 60 wt% sucrose, and otherwise identical preparations gelled by acidification with citric acid at high temperature and cooling from 90 to 25 degrees C at 1 degrees C/min. Two series of experiments were carried out for both methods of acidification. In the first series, the concentration of pectin (c) was held constant at 1.0 wt% and the final pH attained after holding (with GDL) or cooling (with citric acid) was varied from 3.75 to 2.25. In the second series, the final pH was held constant at 3.0 and c was varied from 0.25 to 2.00 wt%. All samples were then heated (1 degrees C/min) from 25 to 90 degrees C. Rheological changes on cooling/holding and heating were characterised by low-amplitude oscillatory measurements of storage modulus (C) and loss modulus (G '') at 1 rad s(-1) and 0.5% strain, and mechanical spectra were recorded at 25 degrees C. Selected samples, gelled with GDL, were also characterised by compression testing (at 25 degrees C), and a direct linear relationship was found between the logarithm of yield stress and log G'. The concentration-dependence of moduli for the samples acidified to pH 3.0 with GDL had the form typical of biopolymer gels, with logG' versus logc approaching a limiting slope of 2 as c was raised above the minimum critical gelling concentration (c(o) approximate to 0.3 wt%). Under all conditions of pH and pectin concentration studied, the values of G '' (at 25 degrees C) for the samples acidified with citric acid were higher than those of the corresponding GDL-induced networks. The values of G' were also higher, except at very low pH (below similar to 2.7 at c = 1.0 wt%) or very high concentrations of pectin. At pectin concentrations above similar to 1.5 wt%, the moduli of the samples gelled with citric acid (at pH 3.0) levelled out, or decreased slightly, with the values of C dropping below those of the GDL-induced networks towards the end of the concentration range studied (at c; 2 wt%). All samples acidified with citric acid showed gel-like response (G' > G '') at 90 degrees C, attributed to hydrophobic association. The downturn in moduli at 25 degrees C for high concentrations of pectin is attributed to formation and disruption of strong networks during mixing with citric acid at high temperature ("pregelation"). It is suggested, however, that "weak gels" formed at lower concentrations or at pH values above similar to 2.7 may enhance gel properties by preserving a continuous network as hydrophobic junctions dissociate on cooling and are replaced by hydrogen-bonded junctions, in contrast to random percolation during gelation with GDL at 25 degrees C. On re-heating from 25 to 90 degrees C, the reverse processes (dissociation of hydrogen-bonded structures and formation of hydrophobic associations) were evident in an initial reduction and subsequent increase in moduli, as observed in previous studies. Similar heating traces were obtained for samples acidified with GDL to pH values above similar to 3.0 (at c = 1.0 wt%) or with pectin concentrations below similar to 1.0 wt% (at pH 3.0). However, at higher concentrations or lower values of pH (i.e. conditions favourable to extensive intermolecular association) an abrupt decrease in C, with an accompanying maximum in G '', was observed on heating through the temperature range similar to 60-80 degrees C. This is attributed to excessive hydrophobic association, causing collapse of network structure. It is further suggested that, for samples acidified with citric acid, there is preferential association of chain sequences of high ester content into hydrophobic junctions at 90 degrees C, leaving sequences with a high content of unesterified carboxyl groups available to form long hydrogen-bonded junctions during cooling, and thus giving gels that are stronger and more resistant to network collapse. (C) 2008 Elsevier Ltd. All rights reserved

ROOFN3D: DEEP LEARNING TRAINING DATA FOR 3D BUILDING RECONSTRUCTION

Machine learning methods have gained in importance through the latest development of artificial intelligence and computer hardware. Particularly approaches based on deep learning have shown that they are able to provide state-of-the-art results for various tasks. However, the direct application of deep learning methods to improve the results of 3D building reconstruction is often not possible due, for example, to the lack of suitable training data. To address this issue, we present RoofN3D which provides a new 3D point cloud training dataset that can be used to train machine learning models for different tasks in the context of 3D building reconstruction. It can be used, among others, to train semantic segmentation networks or to learn the structure of buildings and the geometric model construction. Further details about RoofN3D and the developed data preparation framework, which enables the automatic derivation of training data, are described in this paper. Furthermore, we provide an overview of other available 3D point cloud training data and approaches from current literature in which solutions for the application of deep learning to unstructured and not gridded 3D point cloud data are presented