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In the forming of thermoplastic composite laminates, the temperature‐dependent bending behaviour plays a significant role, in addition to in‐plane tension, in‐plane shear and ply/ply as well as tool/ply friction. The bending properties are decoupled from the in‐plane properties. Classical beam theories are therefore not valid for laminates, as they significantly overestimate the bending stiffness, especially in the molten state. Various approaches to modelling the bending behaviour have been presented in the literature, which can be used to model the out‐of‐plane properties for simulation. With these approaches, a parameter optimisation based on experimental deflection curves is performed through cantilever beam tests. A comparative analysis is then carried out to evaluate the suitability of a temperature and direction dependent modelling of the bending behaviour, the influence of the in‐plane properties and the computation time. [ABSTRACT FROM AUTHOR]

Although renewed interest in flow around groundwater circulation wells is a positive development, the multiple and unacknowledged republication of previously published results is not. This is what has happened in a recent paper published in Water Resources Research by Tu et al. (2020, https://doi.org/10.1029/2020WR027529). The paper repeats results that appeared in Ni et al. (2011, https://doi.org/10.1016/j.applthermaleng.2011.04.030) as well as in the lead authors' own earlier work: Tu et al. (2019, https://doi.org/10.1016/j.applthermaleng.2018.09.029). And all three papers fail to acknowledge that the same ideas and closely related solutions were published in this Journal much earlier by Kabala (1993, https://doi.org/10.1029/92WR01820) and Zlotnik and Ledder (1996, https://doi.org/10.1029/95WR03813). Key Points: Tu et al. (2020) conducted a superficial literature review for flow around groundwater circulation well and missed numerous relevant publications, including those that previously published their resultsAll results claimed as novel by Tu et al. (2020) have been published earlier [ABSTRACT FROM AUTHOR]

Abstract: Soils in mountainous areas are often polygenetic, developed in slope covers that relate to glacial and periglacial activities of the Pleistocene and Holocene and reflect climatic variations. Landscape development during the Holocene may have been influenced by erosion/solifluction that often started after the Holocene climatic optimum. To trace back soil evolution and its timing, we applied a multi‐methodological approach. This approach helped us to outline scenario of soil transformation. According to our results, some aeolian input must have occurred in the late Pleistocene. During that time and the early Holocene, the soils most likely had features of Cryosols or Leptosols. Physico‐chemical and mineralogical analyses have indicated that the material was denudated (between late Boreal to the Atlantic) from the ridge and upper‐slope positions forming a colluvium at mid‐slope positions. Later, during the Sub‐Boreal, mass wasting of the remains of silt material deposited at the end of the Pleistocene age on the ridge top seems to have occurred. In addition, the cool and moist conditions caused the deposition of a colluvium at the lower‐slope positions. The next phase was characterized by the transformation of Leptosols/Cambisols into Podzols at upper‐slope or shoulder positions and to Albic Cambisols at mid‐slope positions. During the Sub‐Boreal period, Stagnosols started to form at the lower part of the slope catena. Overall, the highest erosion rates were calculated at the upper‐slope position and the lowest rates at mid‐slope sites. Berylium‐10 (10Be) data showed that the Bs, BC/C were covered during the Holocene by a colluvium with a different geological composition which complicated the calculation of erosion or accumulation rates. The interpretation of erosion and accumulation rates in such multi‐layered materials may, therefore, be hampered. However, the multi‐methodological reconstruction we applied shed light on the soil and landscape evolution of the eastern Karkonosze Mountains. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

One key limiting factor to groundwater remediation is contaminant sequestered in pores whose contents do not mix well with the bulk flow. Mixing between well-connected (pores whose volume is flushed as water flows through the aquifer) and poorly connected pores (pores whose volume does not exchange readily when water flows through the aquifer) is of primary concern. Under steady flow, contaminants are effectively trapped in the poorly connected pores and are transferred only by molecular diffusion. This slow mixing process between pore types is a bottleneck to remediation. We present a novel rapidly pulsed pumping method that increases the mixing between these pore types. We do it in the context of pump-and-treat remediation because it is the most common remediation practice. In rapidly pulsed pumping, the increase in flow causes a deep sweep, which pushes the flow into poorly connected pores and sweeps out sequestered contaminants. The decrease in flow causes a vortex ejection, which causes the vortex within the poorly connected pore to emerge with contaminant. These actions are modeled with computational fluid mechanics to elucidate the individual mechanisms and determine how they function and interact. Cleanup of single and multiple poorly connected pore systems were simulated and show the acceleration possible. This technique can decrease the time and cost needed to remediate contaminated aquifers, which in the United States has been estimated to exceed $1 trillion. Since our rapidly pulsed pumping method enhances mixing between well-connected and poorly connected pores, it can be applied to other remediation schemes such as in situ methods. [ABSTRACT FROM AUTHOR]

Seasonal variability of Cu, Pb, and Zn concentrations in litter leachates and soil solutions was examined in an afforested zone surrounding a copper smelter in SW Poland. Litter leachates (with zero-tension lysimeters) and soil solutions (with MacroRhizon suction-cup samplers, installed at a depth of 25-30 cm) were collected monthly at three sites differing in contamination levels in the years 2009 and 2010 (total Cu: 2380, 439, and 200 mg kg-1, respectively). Concentrations of Cu in the litter leachate were correlated with dissolved organic C (DOC), whereas Zn and Pb were mainly related to leachate pH. Metal concentrations in the soil solution were weakly influenced by their total content in soils and the monthly fluctuations reached 300, 600, and 700% for Cu, Pb, and Zn, respectively. Metal concentrations in soil solutions (Cu 110-460 μg L-1; Zn 20-1190 μg L-1; Pb 0.5-36 μg L-1) were correlated with their contents in the litter leachates. Chemical speciation, using Visual Minteq 3.0, proved organically-complexed forms even though the correlations between metal concentrations and soil solution pH and DOC were statistically insignificant. The flux of organically-complexed metals from contaminated forest floors is believed to be a direct and crucial factor affecting the actual heavy metal concentrations and their forms in the soil solutions of the upper mineral soil horizons. [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to compare the psychological impact of loop electrosurgical excision procedure ( LEEP) in pre- and postmenopausal women. Material and Methods This was an observational comparative study including 231 pre- and 108 post-menopausal women undergoing LEEP who were subjected to an interview inquiring specific psychological domains concerning the impact of this surgical procedure. The associations between women's answers and their hormonal status were tested by logistic regression analysis. Results Multivariate analysis showed that after LEEP, postmenopausal women were associated with answers that indicated significant psychological changes concerning the impact of cervix disease ( Odds Ratio [ OR] = 2.38, 95% Confidence Interval [ CI] 1.22-4.66), their body image ( OR = 6.80, 95% CI 2.30-20.08), interpersonal relationship with their partner ( OR = 8.32, 95% CI 1.77-38.99) and sexual health quality ( OR = 2.25, 95% CI 1.15-4.39). Conclusion Limited to our sample, the psychological impact of LEEP seems to be greater in postmenopausal than in premenopausal women. We speculate that LEEP could cause failure of psychological domains already weakened by menopause. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To evaluate the diagnostic accuracy of measuring cervical length (CL) in combination with cervical and plasma nitric oxide metabolite (NOx) levels to identify women undergoing preterm labor (PTL) who will deliver preterm. Methods: A hospital-based prospective cohort study of 730 women undergoing spontaneous PTL between 24 and 33weeks+6days of pregnancy was conducted. Measurement of cervical and plasma NOx levels and ultrasonographic assessment of CL were performed to find the best model to predict preterm delivery (PTD). Optimal cut-off values were calculated by receiver operating characteristic (ROC) curve analysis. Logistic regression analysis and rank correlation tests were also performed. Results: CL of 15mm or less, cervical NOx levels greater than 87.6μmol/L, and plasma NOx levels greater than 123μmol/L (P <0.0001) were the only factors significantly associated with PTD within 7days of sampling. This combined model provided high diagnostic accuracy (sensitivity 80.0%; specificity 99.2%). Both cervical and plasma NOx levels were negatively correlated with CL (r =−0.453, P <0.0001 and r =−0.362, P< 0.0001, respectively). Conclusion: Combined measurement of CL and levels of cervical and plasma NOx could help identify women undergoing symptomatic PTL who are at increased risk of PTD. [Copyright &y& Elsevier]

Four soil profiles located near a copper smelter in Poland were investigated for the distribution and chemical fractions of Cu, Pb, and Zn and their mobility in relation to soil properties. Contamination with heavy metals was primarily restricted to surface horizons and the extent of contamination was 7‐ to 115‐fold for Cu, 30‐fold for Pb, and 6‐fold for Zn as compared with subsurface horizons. In the less‐contaminated fine‐textured soil, the metals were distributed in the order: residual >> Fe–Mn oxides occluded > organically complexed > exchangeable and specifically adsorbed, while the order for sandy soils was: residual > organically complexed > Fe–Mn oxides occluded > exchangeable and specifically adsorbed. The contaminated surface horizons of these profiles showed no consistent pattern of metal distribution. However, the common features of highly contaminated soils were very low percentage of residual fraction and the dominance of the NH4OAc extractable fraction. The sum of mobile metal fractions was generally <10% in subsurface horizons, while in the contaminated surface horizons these fractions made up 50% of the total metal contents. Soil properties contributed more to the relative distribution of the metal fractions in the studied profiles than did the distance and direction to the source of pollution. The amounts of metal extracted by 0.01 M CaCl2 accounted for only a small part of the same metals extracted by NH4OAc. The mobility indexes of metals correlated positively and significantly with the total content of metals and negatively with the clay content. [ABSTRACT FROM AUTHOR]

Discusses the paper `Dipole Probe and Field Application of a Single-Borehole Device for Measurements of Vertical Variations of Hydraulic Conductivity,' by Vitaly A. Zlotnik and Brian R. Zurbuchen. Questions on the isotropy assumption; Reply of the authors to the discussion.

Objective To establish prevalence of renal disease, asympotoamtic renal lesions and possible renal symptoms in geographically defined population of individuals with tuberous sclerosis. Patients and methods The study involved 131 patients (64 men, 67 women) with tuberous sclerosis who were resident in nine of the districts within the Wessex Region and three Bristol Health Districts and who had been identified by a prevalence study [1]. The patients' been identified by a prevalence study [1]. The patients' mean age was 22 years (range 6 months-74 years). Established renal disease was identified by history. Where possible individuals were seen were examined. Specific enquiry was made for flank pain and macroscopic haematuria. Renal ultrasound, blood pressure measurement and urine analysis was offered to all individuals with tuberous sclerosis who were resident in the Bath Health District. Results Eight patients (6%) had a history of either renal polycystic kidney disease (two patients) or haemorrhage from renal angiomyolipomas (five female patients, one male patient). A further 21% of female and 3% of male patients had a history of severe flank pain or haematuria. Renal ultrasound screening revealed abnormalities in 10 of 21 individuals; angiomyolipoma > 1 cm were found in seven and were twice as common in female patients. Conclusions Regular clinical review of individuals with tuberous sclerosis should include enquiry for renal symptoms and abdominal examination. Lesions >4cm are most likely to be symptomatic but sound screening of adolescents or adults can be recommended. [ABSTRACT FROM AUTHOR]

- Magnetic resonance imaging (MRI) scans were performed on 55 bladder cancer patients on whom clinicopathological staging was available from transurethral resection and cystectomy specimens. The overall accuracy of MRI scanning in this group was 84%, although true concordance rates are debatable without open surgical correlation. In the subgroup of 25 patients who had accurate open surgical correlation (from cystectomy, laparotomy or post mortem) the concordance rate was 76% with MRI. Errors occurred mainly in the T3 group of tumours, with 2 being overstaged and 2 being understaged out of a total of 12 in the open surgical correlation group (66% accuracy). Difficulties were also encountered in staging tumours at the bladder base, with an error rate of 22% (2 of 9) for T4 tumours in this area. With regard to lymph node staging there was a 100% (5 of 5) specificity in defining pathologically involved nodes but there was a false negative rate of 15% (3 of 19). Although it has many advantages over CT scanning, MRI produces a significant error rate in terms of over-and under-staging invasive tumours. There are difficulties associated with detecting minimal involvement of adjacent organs and lymph nodes as well as determining the exact depth of muscle penetration. Improvements may come in the future with the use of contrast enhancement agents such as gadolinium as well as more advanced machines. [ABSTRACT FROM AUTHOR]

The space-time statistical structure of soil water uptake by oak trees was investigated in a 3.1-m-diameter closed top chamber using a three-dimensional measurement grid of soil moisture and pressure, and measurements of tree transpiration. Using the time domain reflectometery (TDR) measured moisture content, resistance block measured soil water pressure, and a compact constant head permeameter measured saturated hydraulic conductivity, the soil hydraulic properties for the chamber were first estimated. Then, dimensionless statistical measures that utilize the soil water pressure were proposed and used to assess the relative importance of lateral to vertical flow. On the basis of the measured statistical properties of the soil-water pressure, it was found that the vertical flow is at least an order of magnitude larger than the lateral flow, and thus a one-dimensional flow approximation to continuity was utilized. Using continuity and a first-order Taylor series expansion of the Buckingham-Darcy vertical flux about the spatial mean moisture content state, an approximate relation for the time variation of the spatial mean moisture content was derived and tested with the TDR measurements. Despite a large spatial coefficient of variation in the TDR measured moisture content (which was also shown to be comparable to reported values from larger-scale field experiments), good agreement between mean moisture content predictions and measurements were found for two separate drying cycles. The approximate Taylor series flux expansion was utilized for deriving an analogous relation for the time variation of the spatial moisture content variance. The resultant variance budget was used to assess the role of root water uptake on the spatial variability of moisture content. It was found that the root uptake component, which resulted from a covariance between the root water uptake and moisture content spatial perturbations, is comparable to the contribution from soil hydraulic properties and soil water redistribution. One of the main findings in this study is that root water uptake is central to the moisture content spatial variance dissipation especially for dry soil moisture conditions. These results were further investigated using Monte-Carlo simulations. [ABSTRACT FROM AUTHOR]

We evaluate systematic errors inherent in two flowmeter test interpretation methodologies. A physically consistent two-dimensional groundwater flow model is used to numerically simulate the single flowmeter test and the double flowmeter test in 25 different two-layer confined aquifers of a priori known horizontal hydraulic conductivities, K i; specific storativities, S si, and hydraulic diffusivities, v i= K i/ s si, in each layer ( i=1, 2). Values selected for the layer hydraulic parameters span those encountered in natural sandy formations with the ratios of the corresponding parameters in the two layers falling in the following ranges: 1 ≤ K1/ K2 ≤ 100, 0.0001 ≤ S s1/ S s2 ≤ 100, and 1 ≤ V1/ v2 ≤ 10,000. We find that the size of the hydraulic diffusivity contrast rather than the hydraulic conductivity ratio is the dominating factor for the parameter estimation accuracy in the two flowmeter methodologies. For the single flowmeter test methodology the ratio of the estimate over the corresponding true value falls within the range , whereas for the double flowmeter test it falls within . The double flowmeter test also provides estimates of layer specific storativity, S si. These are accurate only for the special case of equal layer hydraulic diffusivities. The test yields order-of-magnitude estimates of S si for layer hydraulic diffusivities differing from each other by up to an order of magnitude. For larger differences the estimation errors are much larger. Hydraulic parameters of a given layer are better estimated when the flowmeter is placed either exactly at the interlayer boundaries or, ideally, at two different points within each layer away from the boundaries. The results from simulated flowmeter tests in a five-layer system are consistent with those for the two-layer aquifers. This implies that the presented results most likely apply to flowmeter tests in arbitrary multilayer aquifers. Existence of significant errors in aquifer parameters estimated from synthetic flowmeter data demonstrate that the Theis [1935] model, which is assumed to be valid in each layer by the two considered interpretation methodologies, does not fully capture the flow dynamics in layered aquifers. This is illustrated by numerically calculated examples of simultaneously nonuniform and transient well face flux distributions in a layered aquifer. A model more sophisticated than that of Theis [1935] needs to be found. [ABSTRACT FROM AUTHOR]

The method of quasi-reversibility (QR) (Lattes and Lions, 1969) has been used previously to solve the diffusion equation with reversed time. We develop a quasi-reversible solution to a convection-dispersion equation by solving the QR diffusion operator in a moving coordinate system. The solution procedure is applied to the problem of recovering the history of a groundwater contaminant plume from observations of its present conditions. This approach to the plume history problem is potentially superior to the Tikhonov regularization approach used by Skaggs and Kabala (1994) because it is easier to implement and readily allows for space- and time-dependent transport parameters. However, our results for a few example problems suggest that the QR procedure is less accurate than the regularization technique. Thus the easy implementation and improved generality of the QR procedure come at the expense of accuracy; this trade-off will have to be weighed if the QR technique is to be used. [ABSTRACT FROM AUTHOR]

The flowmeter test, when modified, can be applied long before the well response reaches a quasi-steady state. In many practical applications the traditional flowmeter test provides only an order of magnitude estimate of the hydraulic conductivity distribution. Conducting the double flowmeter test, i.e., running the flowmeter test on the same borehole twice (at appropriate times), improves the accuracy of the estimated downhole distribution of the hydraulic conductivity and, in addition, provides the downhole distribution of the specific storativity. Formulae for the hydraulic conductivity and specific storativity of each layer are derived for a case of a layered aquifer. The accuracy of the estimated parameter distributions is evaluated via a first-order sensitivity analysis. A formula is also found for the equivalent specific storativity of a layered aquifer. In addition, it is shown that accounting for well bore storage in the flowmeter test leads to an inconsistent model, and hence the flowmeter test should be conducted only after well bore storage effects disappear. [ABSTRACT FROM AUTHOR]

Finding the history of a groundwater contaminant plume from measurements of its current spatial distribution is an ill-posed problem and, consequently, its solution is extremely sensitive to errors in the input data. In this paper, Tikhonov regularization (Tikhonov and Arsenin, 1977) is used in numerical experiments to recover the release history of a plume that has originated from a known, single site. The recovered release history is then used to reconstruct the plume evolution history. The method is found to be insensitive to round off errors, but its accuracy is affected by plume measurement errors, the extent to which the plume has dissipated, and, to a lesser degree, the accuracy of the transport parameter estimates. A regularization approach may be effective at finding a plume history when there are adequate data. [ABSTRACT FROM AUTHOR]

Nuclear magnetic resonance relaxation measurements were used to identify different characteristic porosity domains in soil and aquifer materials. The porosity distribution can be inferred from these measurements by a regularization method applicable to any nuclear magnetic resonance (NMR) relaxation, or by an analytic method applicable only to multiexponential relaxations (D. Orazio et al., 1989). The porosity distribution obtained from NMR relaxation measurements strongly depends on the pore shape factor. For the Borden aquifer material, both the regularized and the analytic pore size distribution obtained from NMR relaxation measurements are consistent with those obtained by Ball et al. (1990) using Hg porosimetry and N2 adsorption. For the Eustis and the Webster soils, the measured porosity domains are qualitatively consistent with those expected based on their respective composition. Our findings suggest that due to the long time required to saturate fine pores, NMR measurements of porosity distribution that are collected at short saturation times are biased toward larger pore sizes. [ABSTRACT FROM AUTHOR]

A new single-borehole measurement technique for confined aquifers, the dipole flow test, yields the vertical distributions of the horizontal hydraulic conductivity, the vertical hydraulic conductivity, and the specific storativity when applied to different borehole intervals. The test utilizes straddle packers to isolate two chambers in the borehole, pressure transducers to monitor drawdown in them, and a small pump to create a dipole flow pattern in the aquifer by pumping water at a constant rate from the aquifer into one chamber, transferring it within the well to the next chamber, and finally injecting it back to the aquifer. A mathematical model describing the drawdown in each chamber is derived for the transient as well as the steady state cases. The aquifer parameters may be estimated from data produced by the dipole flow test alone or in conjunction with conventional pumping tests. The dipole flow regime reaches a steady state relatively quickly, especially in well permeable aquifers. A robust computational methodology for estimating the aquifer parameters, suitable for automatization, is based on the Newton-Raphson algorithm applied to a system of up to three nonlinear equations, each describing the well drawdown at a different judiciously chosen time. Due to the relatively small drawdown it invokes, the dipole flow test may be applicable to unconfined aquifers as well. [ABSTRACT FROM AUTHOR]

The effects of soil heterogeneity on the transport of moisture in the unsaturated zone are studied by means of functional sensitivities, which are more suitable than elementary (or conventional) sensitivities for analyzing continuous systems. The earlier described algorithm is applied to three problems, drainage, infiltration, and exfiltration, for two Miller-similar soils (a randomly generated heterogeneous Yolo light clay and a homogeneous one). It reveals the difference between drainage, on the one hand, and both infiltration and exfiltration on the other. The scaled flux sensitivity profiles, i.e., the functional derivatives of fluxes with respect to Miller-similarity parameter λ( x), are flat for drainage, demonstrating that drainage is equally sensitive to changes in λ( x) at all points of the profile and hence that the similarity parameter has to be modeled well in the whole soil column. Analogous sensitivity profiles for infiltration and exfiltration problems show, significant delay in propagation of functional sensitivities in the soil column (with respect to the moisture front), allowing thus for less stringent modeling of the similarity parameter for the bottom of the column. Infiltration problems seem to be most difficult to deal with, because they are most sensitive to the similarity parameter. [ABSTRACT FROM AUTHOR]

The cumulant expansion method, used previously by Sposito and Barry (1987) to derive an ensemble average transport equation for a tracer moving in a heterogeneous aquifer, is generalized to the case of a reactive solute that can adsorb linearly and undergo first-order decay. In the process we also generalize the Van Kampen (1987) result for the cumulant expansion of a multiplicative stochastic differential equation containing a time-dependent sure matrix. The resulting partial differential equation exhibits terms with field-scale coefficients that are analogous to those in the corresponding nonstochastic local-scale transport equation. There are also new terms in the third- and fourth-order spatial derivatives of the ensemble average concentration. It is demonstrated that the effective solute velocity for the aqueous concentration, not that for the total concentration (aqueous plus sorbed), is relevant for a field-scale description of solute transport. The field-scale effective solute velocity, dispersion coefficient, retardation factor, and first-order decay parameters, unlike their local-scale counterparts, are time-dependent because of autocorrelations and cross correlations among the random local solute velocity, retardation factor, and first-order decay constant. It is shown also that negative cross correlations between the random tracer solute velocity and the inverse of the local retardation factor may produce both enhanced dispersion and a temporal growth in the field-scale retardation factor. These effects are possible in any heterogeneous aquifer for which a stochastic description of aquifer spatial variability is appropriate. [ABSTRACT FROM AUTHOR]

Sensitivity analysis is one of the tools available for analyzing the effects of parameter uncertainty and soil heterogeneity on the transport of moisture in the unsaturated similar porous media. Direct differentiation of the discretized Richards equation with respect to parameters defining spatial variability leads to linear systems of equations for elementary sensitivities that are readily solved in conjunction with the original equation. These elementary sensitivities can be easily transformed into approximations of functional sensitivities and into sensitivities of boundary fluxes. A numerical implementation of this technique in one space dimension yields results that are consistent with exact analytical solutions and with numerical perturbation calculations. The effects of a given heterogeneity can be modeled adequately provided that the maximum relative change of the scale factor from one grid point to the next not exceed a number on the order of unity. [ABSTRACT FROM AUTHOR]

The response of a fully penetrating well to a slug test in a confined aquifer can be described by a single differential equation that is valid for any degree of damping. Although an analytical solution is not available, numerical methods are readily applied. The impact of nonlinear terms becomes significant only when the initial water level displacement is a large fraction of the effective water column height. Previously published approximate solutions for underdamped response are sometimes very accurate. [ABSTRACT FROM AUTHOR]

Focuses on the establishment of the International Church of Pretoria in South Africa. Role of the Church in the provision of spiritual guidance to people; Influence of the French-speaking foreigners on the establishment of the Church; Composition of the members of the Church; Challenges and struggles experienced by the Church's members.

A non-linear least-squares (NLS) method is used without regularization to recover the release history of a groundwater contaminant plume from its current measured spatial distribution. The flow system is assumed to be one-dimensional, with the plume originating from a known single site. The solution is found to be very sensitive to noise and to the extent to which the plume is dissipated. Although the NLS method is extremely sensitive to measurement errors for the gradual release scenario, it can resolve the release histories for catastrophic release scenarios reasonably well, even in the presence of moderate measurement errors. A number of synthetic numerical examples are analysed. We find that for catastrophic contaminant releases the NLS method may be an alternative to the Tikhonov regularization approach. [ABSTRACT FROM AUTHOR]

Steady-state numerical simulations of the dipole flow test in layered aquifers demonstrate that the test produces a good estimate of the equivalent hydraulic conductivity anisotropy ratio for the part of the aquifer spanned by the well chambers. The effects of chamber size, different conductivity of layers and layer location on the estimated anisotropy ratios are presented. The steady-state dipole flow test, when performed at different levels in the well, can yield estimates ofthe down-hole anisotropy ratio distribution. Numerical simulations also illustrate that the skin effect can significantly distort the anisotropy estimates produced by the dipole flow test. [ABSTRACT FROM AUTHOR]

Forty-four patients undergoing magnetic resonance imaging (MRI) head scans for non-nasal disease were asked to complete a questionnaire immediately after the scan. Subjective patency was scored for each nasal airway, patients were also asked about other nasal symptoms, hay fever, upper respiratory tract infections, medication and any history of nasal surgery or trauma. The following measurements from MRI scans were made: the cross-sectional area of the nasal airway at the anterior end of the middle turbinate, the horizontal width of the inferior turbinate and maximum septal mucosal thickness. In addition the presence of any septal deviation and the thickness or the mucosa of the paranasal sinuses was assessed. Correlation between subjective airway patency and the anatomical parameters studied was generally very weak. However, patients with sinus mucosal thickening on MRI scanning had significantly lower subjective patency scores (left P = 0.003, right P = 0.029) for both nasal airways. Assessment of the nasal airway on MRI correlates poorly with symptoms of nasal obstruction. However, patients with sinus mucosal thickening ( > 5 mm) had significantly more symptoms of nasal obstruction on both sides. [ABSTRACT FROM AUTHOR]

Background: Variations in the thickness of the nasal septum are well documented1 although their relation to nasal obstruction is unclear. Objective methods of assessing the nasal airway correlate poorly with subjective patency.2 Objective: To determine if septal mucosal thickness and other parameters derived from MRI imaging correlate significantly with subjective sensation of nasal resistance. Methods: Forty patients undergoing MRI head scans for non-nasal disease were asked to complete a questionnaire immediately prior to the scan being taken. Subjective patency was scored for each nasal airway, patients were also asked about hayfever, URTIs, medication and history of nasal surgery or trauma. Scans were assessed using image analysis software. The following parameters were assessed at the level of the nasal valve: cross-sectional area of airway, horizontal thickness of inferior turbinate and maximum septal mucosal thickness. In addition, the presence of septal deviation (lateral to the vertical plane of the middle turbinate), and sinus mucosal thickening of 4 mm or more was assessed. Repeatability and inter-observer error was calculated. Data was analysed using non-parametric tests and multiple stepwise regression. Results: Overall correlation between anatomical parameters and subjective patency was low. Patients with sinus mucosal thickness greater than 4 mm on MRI scanning had subjectively poorer nasal airways (left P = 0.003, right P = 0.029). Multiple regression confirmed sinus mucosal thickening as the most significant predictor of patency but also negative correlation between ipsilateral mucosal thickness and patency (P < 0.002) and positive correlation between contralateral turbinate thickness (P < 0.01) and patency. Conclusions: Anatomical factors in both ipsilateral and contralateral nasal airways are of... [ABSTRACT FROM AUTHOR]