LNAPLs do not Always Float: An Example Case of a Viscous LNAPL under Variable Water Table Conditions

An intermediate-scale experiment was conducted to investigate the behavior of a viscous LNAPL under variable water table conditions. Two LNAPL volumes were released from a small source zone on top of the flow cell into a partly saturated, homogeneously packed porous medium. Following a 30-day redistribution period, the water table was increased 0.5 m in 50 minutes. After the water table rise, LNAPL behavior was monitored for an additional 45 days. Fluid saturation scans were obtained periodically with a fully automated dual-energy gamma radiation system. Results show that both spills follow similar paths downwards. LNAPL drainage from the unsaturated zone was relatively slow and a considerable residual LNAPL saturation was observed after 30 days of drainage. Most of the mobile LNAPL moved into the capillary fringe during this period. After the water table rise, LNAPL moved up in a delayed fashion. After 45 days, the LNAPL has moved up only approximately 0.2 m. Since the LNAPL has only moved up a limited amount, nonwetting fluid entrapment was also limited. The experiment was simulated using the STOMP multifluid flow simulator. A comparison indicates that the simulator is able to predict the observed phenomena well, including residual saturation formation in the vadose zone, and limited upward LNAPL movement after the water table rise. The results of this experiment show that viscous mobile LNAPL, subject to variable water table conditions, does not necessarily float on the water table and may not appear in an observation well

The Connective Tissue Disorder Associated with Recessive Variants in the SLC39A13 Zinc Transporter Gene (Spondylo-Dysplastic Ehlers-Danlos Syndrome Type 3): Insights from Four Novel Patients and Follow-Up on Two Original Cases.

Recessive loss-of-function variants in SLC39A13, a putative zinc transporter gene, were first associated with a connective tissue disorder that is now called "Ehlers-Danlos syndrome, spondylodysplastic form type 3" (SCD-EDS, OMIM 612350) in 2008. Nine individuals have been described. We describe here four additional affected individuals from three consanguineous families and the follow up of two of the original cases. In our series, cardinal findings included thin and finely wrinkled skin of the hands and feet, characteristic facial features with downslanting palpebral fissures, mild hypertelorism, prominent eyes with a paucity of periorbital fat, blueish sclerae, microdontia, or oligodontia, and-in contrast to most types of Ehlers-Danlos syndrome-significant short stature of childhood onset. Mild radiographic changes were observed, among which platyspondyly is a useful diagnostic feature. Two of our patients developed severe keratoconus, and two suffered from cerebrovascular accidents in their twenties, suggesting that there may be a vascular component to this condition. All patients tested had a significantly reduced ratio of the two collagen-derived crosslink derivates, pyridinoline-to-deoxypyridinoline, in urine, suggesting that this simple test is diagnostically useful. Additionally, analysis of the facial features of affected individuals by DeepGestalt technology confirmed their specificity and may be sufficient to suggest the diagnosis directly. Given that the clinical presentation in childhood consists mainly of short stature and characteristic facial features, the differential diagnosis is not necessarily that of a connective tissue disorder and therefore, we propose that SLC39A13 is included in gene panels designed to address dysmorphism and short stature. This approach may result in more efficient diagnosis

The reliability of the patellotrochlear index on magnetic resonance imaging for measuring patellofemoral height

Background: The purpose of this study was to determine the inter-and intra-observer reliability of the patellotrochlear index (PTI) on magnetic resonance images (MRI) in patients with patellofemoral pain. The correlation between the PTI measured on MRI and the modified Insall-Salvati (MIS) ratio measured on radiographs was also assessed. Methods: The PTI was assessed on MRI images and the MIS ratio on radiographs of 66 knees of 62 patients. Assessment was performed by two orthopaedic surgeons, one orthopaedic surgery registrar, two radiologists and one radiology registrar. Correlation coefficients, standard errors of measurement and limits of agreement were calculated for the PTI. To assess the association between the PTI and the MIS ratio, the Pearson's correlation coefficient was calculated. Results: The PTI showed good interobserver reliability (intraclass correlation coefficient (ICC) 0.79; 95% confidence interval (CI) 0.73-0.85) and excellent intra-observer reliability (ICC 0.90; 95% CI 0.89-0.91). The standard error of measurement was 0.05 and limits of agreement with the mean +/- 0.09. A very weak and not significant correlation was found between the PTI and the MIS (r = 0.02; P = 0.77). Conclusions: The PTI showed good interobserver reliability and excellent intra-observer reliability. In order to conclude which measurement method of assessing patellar height is truly the most reliable, future studies should investigate agreement parameters (standard error of measurement, limits of agreement) besides solely correlation coefficients. We found a very weak correlation between the PTI and the MIS which suggests that at least one index has poor validity. Future validity studies on indices to assess patellar height are necessary. (c) 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

The Clinical Spectrum of Missense Mutations of the First Aspartic Acid of cbEGF-like Domains in Fibrillin-1 Including a Recessive Family

Marfan syndrome (MFS) is a dominant disorder with a recognizable phenotype. In most patients with the classical phenotype mutations are found in the fibrillin-1 gene (FBN1) on chromosome 15q21. It is thought that most mutations act in a dominant negative way or through haploinsufficiency. In 9 index cases referred for MFS we detected heterozygous missense mutations in FBN1 predicted to substitute the first aspartic acid of different calcium-binding Epidermal Growth Factor-like (cbEGF) fibrillin-1 domains. A similar mutation was found in homozygous state in 3 cases in a large consanguineous family. Heterozygous carriers of this mutation had no major skeletal, cardiovascular or ophthalmological features of MFS. In the literature 14 other heterozygous missense mutations are described leading to the substitution of the first aspartic acid of a cbEGF domain and resulting in a Marfan phenotype. Our data show that the phenotypic effect of aspartic acid substitutions in the first position of a cbEGF domain can range from asymptomatic to a severe neonatal phenotype. The recessive nature with reduced expression of FBN1 in one of the families suggests a threshold model combined with a mild functional defect of this specific mutation. © 2010 Wiley-Liss, Inc

Red blood cell glutathione peroxidase activity in female nulligravid and pregnant rats

<p>Abstract</p> <p>Background</p> <p>The alterations of the glutathione peroxidase enzyme complex system occur in physiological conditions such as aging and oxidative stress consequent to strenuous exercise.</p> <p>Methods</p> <p>Authors optimize the spectrophotometric method to measure glutathione peroxidase activity in rat red blood cell membranes.</p> <p>Results</p> <p>The optimization, when applied to age paired rats, both nulligravid and pregnant, shows that pregnancy induces, at seventeen d of pregnancy, an increase of both reactive oxygen substance concentration in red blood cells and membrane glutathione peroxidase activity.</p> <p>Conclusion</p> <p>The glutathione peroxidase increase in erythrocyte membranes is induced by systemic oxidative stress long lasting rat pregnancy.</p

Modifying Hofstee standard setting for assessments that vary in difficulty, and to determine boundaries for different levels of achievement.

BACKGROUND: Fixed mark grade boundaries for non-linear assessment scales fail to account for variations in assessment difficulty. Where assessment difficulty varies more than ability of successive cohorts or the quality of the teaching, anchoring grade boundaries to median cohort performance should provide an effective method for setting standards. METHODS: This study investigated the use of a modified Hofstee (MH) method for setting unsatisfactory/satisfactory and satisfactory/excellent grade boundaries for multiple choice question-style assessments, adjusted using the cohort median to obviate the effect of subjective judgements and provision of grade quotas. RESULTS: Outcomes for the MH method were compared with formula scoring/correction for guessing (FS/CFG) for 11 assessments, indicating that there were no significant differences between MH and FS/CFG in either the effective unsatisfactory/satisfactory grade boundary or the proportion of unsatisfactory graded candidates (p > 0.05). However the boundary for excellent performance was significantly higher for MH (p < 0.01), and the proportion of candidates returned as excellent was significantly lower (p < 0.01). MH also generated performance profiles and pass marks that were not significantly different from those given by the Ebel method of criterion-referenced standard setting. CONCLUSIONS: This supports MH as an objective model for calculating variable grade boundaries, adjusted for test difficulty. Furthermore, it easily creates boundaries for unsatisfactory/satisfactory and satisfactory/excellent performance that are protected against grade inflation. It could be implemented as a stand-alone method of standard setting, or as part of the post-examination analysis of results for assessments for which pre-examination criterion-referenced standard setting is employed

Physical therapy plus general practitioners’ care versus general practitioners’ care alone for sciatica: a randomised clinical trial with a 12-month follow-up

A randomised clinical trial in primary care with a 12-months follow-up period. About 135 patients with acute sciatica (recruited from May 2003 to November 2004) were randomised in two groups: (1) the intervention group received physical therapy (PT) added to the general practitioners’ care, and (2) the control group with general practitioners’ care only. To assess the effectiveness of PT additional to general practitioners’ care compared to general practitioners’ care alone, in patients with acute sciatica. There is a lack of knowledge concerning the effectiveness of PT in patients with sciatica. The primary outcome was patients’ global perceived effect (GPE). Secondary outcomes were severity of leg and back pain, severity of disability, general health and absence from work. The outcomes were measured at 3, 6, 12 and 52 weeks after randomisation. At 3 months follow-up, 70% of the intervention group and 62% of the control group reported improvement (RR 1.1; 95% CI 0.9–1.5). At 12 months follow-up, 79% of the intervention group and 56% of the control group reported improvement (RR 1.4; 95% CI 1.1; 1.8). No significant differences regarding leg pain, functional status, fear of movement and health status were found at short-term or long-term follow-up. At 12 months follow-up, evidence was found that PT added to general practitioners’ care is only more effective regarding GPE, and not more cost-effective in the treatment of patients with acute sciatica than general practitioners’ care alone. There are indications that PT is especially effective regarding GPE in patients reporting severe disability at presentation

Expanding the genetic and phenotypic spectrum of ACTA2-related vasculopathies in a Dutch cohort

Purpose: Heterozygous pathogenic/likely pathogenic (P/LP) variants in the ACTA2 gene confer a high risk for thoracic aortic aneurysms and aortic dissections. This retrospective multicenter study elucidates the clinical outcome of ACTA2-related vasculopathies. Methods: Index patients and relatives with a P/LP variant in ACTA2 were included. Data were collected through retrospective review of medical records using a standardized questionnaire. Results: A total of 49 individuals from 28 families participated in our study. In total, 20 different ACTA2 variants were detected. Aortic events occurred in 65% of the cases (78.6% index patients and 47.6% relatives). Male sex and hypertension emerged as significantly associated with aortic events. Of 20 individuals, 5 had an aortic diameter of <45 mm (1.77 inches) at the time of the type A dissection. Mean age at first aortic event was 49.0 ± 12.4 years. Severe surgical complications for type A and type B dissection occurred in 25% and 16.7% of the cases and in-hospital mortality rates were 9.5% and 0%, respectively. Conclusion: P/LP ACTA2 variants are associated with an increased risk for an aortic event and age-related penetrance, which emphasizes the importance of early recognition of the disease. Caregivers should be aware of the risk for aortic dissections, even in individuals with aortic diameters within the normal range

Patients Enrolled in Large Randomized Clinical Trials of Antiplatelet Treatment for Prevention After Transient Ischemic Attack or Ischemic Stroke Are Not Representative of Patients in Clinical Practice: the Netherlands Stroke Survey

Background and Purpose—Many randomized clinical trials have evaluated the benefit of long-term use of antiplatelet drugs in reducing the risk of new vascular events in patients with a recent transient ischemic attack or ischemic stroke. Evidence from these trials forms the basis for national and international guidelines for the management of nearly all such patients in clinical practice. However, abundant and strict enrollment criteria may limit the validity and the applicability of results of randomized clinical trials to clinical practice. We estimated the eligibility for participation in landmark trials of antiplatelet drugs of an unselected group of patients with stroke or transient ischemic attack from a national stroke survey. Methods—Nine hundred seventy-two patients with transient ischemic at