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Quantitative description of root-water uptake under combined salinity and water stress is needed to optimize crop yields and water management in arid and semiarid regions. This study was conducted to develop a simple macroscopic root-water uptake model for nonuniform transient soil water content and salinity conditions in the root zone. This new model and previous models were tested against detailed experimental data obtained with Alfalfa (Medicago sativa L.) grown in the greenhouse in packed sandy loam (Typic Haplaquent) columns. Soil water content, pressure head, and osmotic head distributions in the root zone were varied by means of the amounts, application intervals, and salinities of the irrigation water. Experimental data under separate and combined stresses were used to test the various models using mean values of soil solution osmotic and pressure heads. The simple additive reduction function provided the worst agreement with the experimental data, while for most cases the multiplicative reduction functions could not adequately account for both water and salinity stress conditions. The newly proposed linear reduction function is neither additive nor multiplicative, but was assumed that both the intersect and slope of the reduction function increased with salinity. This model provided excellent agreement with the experimental data, particularly at higher soil solution salinities. The new reduction function could be used with any other nonlinear salinity reduction function.

Comparison of six different laboratory methods for obtaining hydraulic diffusivity and conductivity on eolian silt loam, eolian sand, fluviatile silt loam and marine sandy loam reveals that all the methods yield different results. The information about soil hydraulic properties is essential for the development of soil-waterflow models, making the accurate determination of the properties important. The comparison of the different methods could not be effectively performed due to hysteresis.

Automatic atomized water spray system is used to measure the soil hydraulic conductivity as function of volumetric water content. This technique enables the accurate prediction of soil hydraulic conductivities between saturation and values around 0.1 mm/d. Simultaneous measurements with time-domain reflectometry exhibit the hydraulic conductivity as a single-valued function of water content.

Researchers compared the Topp-Davis-Annan calibration equation with a theoretical (Maxwell-De Loor) and an empirical (fitting exponent alpha) mixing construct for the solid phase (s), tightly bound water (bw), free water and air components. The Maxwell-De Loor equation allows for effects and ostensible anomalous behavior such as falling effective Epsilon with rising Epsilon s, which shows that it is the better calibration equation.

The development of surface seals on soils under different rain intensities is affected by erosion, runoff and infiltration. In an experiment conducted to study the evolution of soil horizons under different rain intensities, high values for surface seal conductances occurred when the seal was partially open. Maximum thickening of the surface seal and minimum macroporosity was observed five minutes after intensity peak. Soil erosion was heightened with continous rain as the surface seal thinned out and total porosity in terms of planar voids increased.

Aim: There is considerable heterogeneity in outcomes in studies reporting on the treatment of haemorrhoidal disease (HD). The aim of this study was to develop a Core Outcome Set (COS) for HD in cooperation with the European Society of Coloproctology. Method: A Delphi study was performed according to the Outcome Measures in Rheumatology (OMERACT) methodology. In total 38 healthcare professionals and 30 patients were invited to the panel. Previously, 10 outcome domains and 59 outcomes were identified through a systematic literature review. In this study, these domains and outcomes were formed into one questionnaire for healthcare professionals and a separate questionnaire for patients. Sequential questionnaire rounds prioritizing the domains and outcomes were conducted. Panel members were asked to rate the appropriateness of each domain and outcome on a nine‐point Likert scale. During a face‐to‐face meeting, healthcare professionals agreed on the primary and secondary end‐points of the COS for HD. Finally, a short survey was sent to the healthcare professionals in order to reach consensus on how the chosen end‐points should be assessed and at which time points. Results: The response rate in questionnaire round 1 for healthcare professionals was 44.7% (n = 17). Sixteen out of 17 healthcare professionals also completed the questionnaire in round 2. The response rate for the patient questionnaire was 60% (n = 18). Seventeen healthcare professionals participated in the face‐to‐face meeting. The questionnaire rounds did not result in a clear‐cut selection of primary and secondary end‐points. Most domains and outcomes were considered important, and only three outcomes were excluded. During the face‐to‐face meeting, agreement was reached to select the domain 'symptoms' as primary end‐point, and 'complications', 'recurrence' and 'patient satisfaction' as secondary end‐points in the COS for HD. Furthermore, consensus was reached that the domain 'symptoms' should be a patient reported outcome measure and should include the outcomes 'pain' and 'prolapse', 'itching', 'soiling' and 'blood loss'. The domain 'complications' should include the outcomes 'incontinence', 'abscess', 'urinary retention', 'anal stenosis' and 'fistula'. Consensus was reached to use 'reappearance of initial symptoms' as reported by the patient to define recurrence. During an additional short survey, consensus was reached that 'incontinence' should be assessed by the Wexner Fecal Incontinence Score, 'abscess' by physical examination, 'urinary retention' by ultrasonography, 'anal stenosis' by physical examination, and 'fistula' by physical examination and MR imaging if inconclusive. During follow‐up, the outcome 'symptoms' should be assessed at baseline, 7 days, 6 weeks and 1 year post‐procedure. The outcomes 'abscess' and 'urinary retention' should be assessed 7 days post‐procedure and 'incontinence', 'anal stenosis' and 'fistula' 1 year post‐procedure. Conclusions: We developed the first European Society of Coloproctology COS for HD based on an international Delphi study among healthcare professionals. The next step is to incorporate the patients' perspective in the COS. Use of this COS may improve the quality and uniformity of future research and enhance the analysis of evidence. [ABSTRACT FROM AUTHOR]

The electrical permittivity of soil is a function of the water content, which facilitates water content measurements. The permittivity of soil is also a function of the frequency of the applied electric field. This frequency dependence can be described by the relationship between the dielectric relaxation frequency and the activation enthalpy of the water, which in turn is related to the soil matric pressure. The activation enthalpy or soil matrix pressure is a measure of the binding forces acting on a water molecule in the soil matrix. Each water molecule is differently bound, varying from tightly bound to free water. The permittivity of the bulk soil results from the contribution of all the water molecules in the soil matrix. Therefore, the permittivity of soil as a function of frequency is related to the soil matrix pressure. It is realistic to consider hygroscopic water as ice like. A relatively sharp transition can be observed from free to hygroscopic water at matric pressure -- 100 MPa corresponding to relaxation frequency [f.sub.r] [approximately equals] 8 GHz. Therefore, for the interpretation of dielectric data using a dielectric mixture equation, the water content of soil can be split conveniently in 'free' water and 'hygroscopic' water.

A change in the relative proportions of the constituents of a porous material like soil will cause a change in its electrical permittivity. The measured permittivity reflects the impact of the permittivities of the individual material constituents. Numerous dielectric mixture equations are published, but none of these equations are generally applicable. A new theoretical mixture equation is derived, using the principle of superposition of electric (E) fields. This mixture equation relates the measured permittivity to a weighted sum of the permittivities of the individual material constituents and includes depolarization factors to account for electric field refractions at the interfaces of the constituents. The depolarization factors are related to physical properties of the material. Most other mixture equations contain one or more empirical factors. The concept of the depolarization factor is comparable with that of the 'shape factor' of particles as described by other authors. A special case of the new mixture equation, for which the depolarization factors equals one (no depolarizations), appeared equal to a mixture equation for fluids derived from using thermodynamics. The new mixture equation is compared with other mixture equations. Comparison of the new mixture equation with measured data for glass beads and fine sand was promising. Concluding, depolarization factors in the new mixture equation relate the microstructural and compositional material properties to the measured bulk permittivity of a material. Although not shown, depolarization factors can be calculated from physical material properties.

Aim This study aimed to assess the cost-effectiveness of sacral neuromodulation ( SNM) compared with conservative treatment in children and adolescents with constipation refractory to conservative management. Method A Markov probabilistic model was used, comparing costs and effectiveness of SNM and conservative treatment in children and adolescents aged 10-18 years with constipation refractory to conservative management. Input for the model regarding transition probabilities, utilities and healthcare costs was based on data from a cohort of patients treated in our centre. This cohort consisted of 30 female patients (mean age 16 years) with functional constipation refractory to conservative management. The mean duration of laxative use in this group was 5.9 years. All patients had a test SNM, followed by a permanent SNM in 27/30. Median follow-up was 22.1 months (range 12.2-36.8). The model was run to simulate a follow-up period of 3 years. Results The mean cumulative costs for the SNM group and the conservative treatment group were €17 789 ( SD €2492) and €7574 ( SD €4332) per patient, respectively. The mean quality adjusted life years ( QALYs) in the SNM group was 1.74 ( SD 0.19), compared with 0.86 ( SD 0.14) in the conservatively managed group. The mean incremental cost-effectiveness ratio was €12 328 per QALY ( SD €4788). Sensitivity analysis showed that the outcomes were robust to a wide range of model assumptions. Conclusion Chronic constipation seriously affects the quality of life of children and adolescents. Preliminary evidence suggests that SNM can improve symptoms and quality of life at a reasonable cost. [ABSTRACT FROM AUTHOR]

Purpose: Over the last decade, many studies were performed regarding treatment options for hemorrhoidal disease. Randomised controlled trials (RCTs) should have well-defined primary and secondary outcomes. However, the reported outcome measures are numerous and diverse. The heterogeneity of outcome definition in clinical trials limits transparency and paves the way for bias. The development of a core outcome set (COS) helps minimizing this problem. A COS is an agreed minimum set of outcomes that should be measured and reported in all clinical trials of a specific disease. The aim of this project is to generate a COS regarding the outcome of treatment after hemorrhoidal disease. Methods: A Delphi study will be performed by an international steering group healthcare professionals and patients with the intention to create a standard outcome set for future clinical trials for the treatment of hemorrhoidal disease. First, a literature review will be conducted to establish which outcomes are used in clinical trials for hemorrhoidal disease. Secondly, both healthcare professionals and patients will participate in several consecutive rounds of online questionnaires and a face-to-face meeting to refine the content of the COS. Discussion: Development of a COS for hemorrhoidal disease defines a minimum outcome-reporting standard and will improve the quality of research in the future. [ABSTRACT FROM AUTHOR]

Study Question: What is the cost-effectiveness of elective single embryo transfer (eSET) versus double embryo transfer (DET) strategies from a societal perspective, when applying a time horizon of 1, 5 and 18 years?Summary Answer: From a short-term perspective (1 year) it is cost-effective to replace DET with single embryo transfer; however when intermediate- (5 years) and long-term (18 years) costs and consequences are incorporated, DET becomes the most cost-effective strategy, given a ceiling ratio of €20 000 per quality-adjusted life years (QALY) gained.What Is Already Known: According to previous cost-effectiveness research into embryo transfer strategies, DET is considered cost-effective if society is willing to pay around €20 000 for an extra live birth. However, interpretation of those studies is complicated, as those studies fail to incorporate long-term costs and outcomes and used live birth as a measure of effectiveness instead of QALYs. With this outcome, both multiple and singletons were valued as one live birth, whereas costs of all children of a multiple were incorporated.Study Design, Size, Duration: A Markov model (cycle length: 1 year; time horizon: 1, 5 and 18 years) was developed comparing a maximum of: (i) three cycles of eSET in all patients; (ii) four cycles of eSET in all patients; (iii) five cycles of eSET in all patients; (iv) three cycles of standard treatment policy (STP), i.e. eSET in women <38 years with a good quality embryo, and DET in all other women; and (v) three cycles of DET in all patients.Participants/materials, Setting, Methods: Expected life years (LYs), child QALYs and costs were estimated for all comparators. Input parameters were derived from a retrospective cohort study, in which hospital resource data were collected (n=580) and a parental questionnaire was sent out (431 respondents). Probabilistic sensitivity analysis (5000 iterations) was performed.Main Results and the Role Of Chance: With a time horizon of 18 years, DETx3 is most effective (0.54 live births, 10.2 LYs and 9.8 QALYs) and expensive (€37 871) per couple starting IVF. Three cycles of eSET are least effective (0.43 live births, 7.1 LYs and 6.8 QALYs) and expensive (€25 563). We assumed that society is willing to pay €20 000 per QALY gained. With a time horizon of 1 year, eSETx3 was the most cost-effective embryo transfer strategy with a probability of being cost-effective of 99.9%. With a time horizon of 5 or 18 years, DETx3 was most cost-effective, with probabilities of being cost-effective of 77.3 and 93.2%, respectively.Limitations, Reasons For Caution: This is the first study to use QALYs generated by the children in the economic evaluation of embryo transfer strategies. There remains some disagreement on whether QALYs generated by new life should be used in economic evaluations of fertility treatment. A further limitation is that treatment ends when it results in live birth and that only child QALYs were considered as measure of effectiveness. The results for the time horizon of 18 years might be less solid, as the data beyond the age of 8 years are based on extrapolation.Wider Implications Of the Findings: The current Markov model indicates that when child QALYs are used as measure of outcome it is not cost-effective on the long term to replace DET with single embryo transfer strategies. However, for a balanced approach, a family-planning perspective would be preferable, including additional treatment cycles for couples who wish to have another child. Furthermore, the analysis should be extended to include QALYs of family members.Study Funding/competing Interests: This study was supported by a research grant (grant number 80-82310-98-09094) from the Netherlands Organization for Health Research and Development (ZonMw). There are no conflicts of interest in connection with this article.Trial Registration Number: Not applicable. [ABSTRACT FROM AUTHOR]

Using orthogonal design, we created a questionnaire containing 16 cases of twin pregnancies. For each case, respondents indicated whether they would plan a vaginal delivery (VD) or a caesarean section (CS). We assessed the association between each variable (maternal age, parity, mode of conception, gestational age, chorionicity, body mass index, foetal growth, foetal presentation and wish for additional children) and the planned mode of delivery. A VD was planned mostly for vertex presentation of twin A (vertex–vertex vs. non-vertex–vertex, odds ratio [OR]: 0.002, 95% confidence interval [CI]: 0.001–0.003,p< 0.001). For vertex– non-vertex (vs. vertex–vertex) presentation, chances on planning a VD decreased threefold (OR: 0.29, 95% CI: 0.018–0.46,p< 0.001), although the majority of respondents would still plan a VD. In multiparous (vs. nulliparous) women, VD was chosen more often (OR: 3.24, 95% CI: 2.50–4.18,p< 0.001).Vertex presentation of twin A and multiparity were the main reasons for planning a VD. [ABSTRACT FROM PUBLISHER]

Objective: This study aims to determine the impact of using a prediction model for recurrent preeclampsia to customize antenatal care in subsequent pregnancies.Methods: We compared care consumption, pregnancy outcomes, and self-reported health state of two risk-based subgroups, and compared these to a reference group receiving standard care.Results: We included a total of 311 women from 12 hospitals. Compared to standard care, recurrence-risk guided care did not lead to different outcomes or self-perceived health.Conclusion: Our study exemplifies that recurrence-risk-based stratification of antenatal care in former preeclampsia patients is feasible; it does not lead to worse pregnancy outcomes. [ABSTRACT FROM AUTHOR]

STUDY QUESTION: To what extent are outcome measures in endometriosis-related quality of life studies influenced by the setting in which patient recruitment is performed? SUMMARY ANSWER: Quality of life outcomes in women with endometriosis are highly influenced by recruitment strategies. WHAT IS KNOWN ALREADY: Most studies on quality of life in women with endometriosis are conducted in tertiary care centres or patient associations. It is conceivable that the setting in which patient recruitment is performed influences the quality of life results. This has not been investigated before. STUDY DESIGN, SIZE, DURATION: Retrospective questionnaire based cohort study (part of the World Endometriosis Research Foundation (WERF) EndoCost study). The investigated women were recruited in three settings: a tertiary care centre for endometriosis (n = 135); five secondary care centres (n = 63); an endometriosis patient association (n = 291). PARTICIPANTS/MATERIALS, SETTING, METHODS: The secondary and tertiary care population included women with a laparoscopic and/or histological diagnosis of endometriosis. The patient association population consisted of women with a self-reported diagnosis of surgically confirmed endometriosis. MAIN RESULTS AND THE ROLE Of CHANCE: The populations did not differ in terms of age, co-morbidities and education level. Delay of diagnosis was the longest in the patient association (median 7 years) (tertiary care 2 years; secondary care 1.5 years) (P < 0.001). The tertiary care population reported more laparotomies (64%) than the other populations (secondary care 43%; patient association 47%) (P = 0.002). Affected job was least prevalent in the secondary care setting (35%) (patient association 64%; tertiary care 56%) (P < 0.001). Affected relationships were most prevalent in the patient association setting (52%) (tertiary care 38%; secondary care 22%) (P < 0.001). Chronic pain was least prevalent in patients in secondary care (44%) (tertiary care 65%; patient association 61%) (P = 0.009). Substantial differences in quality of life were detected between secondary care (median physical component 50.4, mental component 49.6); tertiary care (physical component 46.2, mental component 46.2) and the patient association (physical component 45.0, mental component 44.6) (P < 0.001, P = 0.018). LIMITATIONS, REASONS FOR CAUTION: The response rate was relatively low (35%). Analysis of the hospital populations revealed that non-responders and responders did not differ with respect to age or revised American Fertility Society classification, indicating that the non-responder bias is limited. However, other factors, such as social and marital status or symptomatology, might be different for non-responders. Missing values were analysed as if the symptom was not present. Missing values never exceeded 10%, except for one value. Therefore, it can be expected that the effect of missing data on the outcome is negligible. Twenty-five patients belonged to more than one category. A sensitivity analysis showed that the influence of assigning patients to another category was limited. WIDER IMPLICATIONS Of THE FINDINGS: Outcomes regarding quality of life are highly influenced by recruitment strategy. None of the groups appeared to be a representative selection of the total population of women with endometriosis. An alternative strategy for creating a representative population for cost and quality of life studies is probably to recruit women who live in a specific geographic area rather than women that visit a specific hospital or are a member of a patient association. STUDY FUNDING/COMPETING INTEREST(S): The WERF EndoCost study was funded by the World Endometriosis Research Foundation. The sponsors did not have a role in the design and conduct of this study: collection, management, analysis, interpretation of the data; preparation, review, approval of the manuscript. L.H. is the chief executive and T.M.D. was a board member of WERF at the time of funding. T.M.D holds the Merck-Serono Chair and the Ferring Chair in Reproductive Medicine in Leuven, Belgium and has served as consultant for Merck-Serono, Schering-Plough, Astellas, and Arresto. [ABSTRACT FROM AUTHOR]

Objective: To validate a previously published prediction model for recurrent early-onset preeclampsia (PE). Methods: We included 229 pregnant women with a history of early-onset PE and computed their risk using the prediction model, compared the predicted risk to their pregnancy outcomes and assessed performance of the model. Results: Early-onset PE recurred in 6.6% of participants. The area under the receiver operating characteristic curve was 59% (95% CI: 45-73). The model created groups that were only moderately different in terms of their risk. Conclusions: The model's discriminate ability was poor and predictive performance insufficient to classify women into relevant risk groups. [ABSTRACT FROM AUTHOR]