Scheimpflug-based analysis of the reflectivity of the cornea in Marfan Syndrome

Purpose:We sought to investigate corneal reflectivity inMarfan syndrome (MFS) on the basis of Scheimpflug light intensity distribution. Methods: In a retrospective case-control analysis, the left eyes of 40 MFS patients and 40 age- and refraction-matched healthy controls were investigated. Patients with MFS meeting the Ghent II diagnostic criteria and with genetic confirmation of disease were included. Exclusion criteria were the following: Coexisting corneal, conjunctival, or scleral pathology, use of medication known to affect corneal transparency, history of ocular surgery, and insufficient data. Scheimpflug tomography images were exported to analyze corneal transparency in different corneal layers and regions. Each corneal image was automatically segmented, after which the corresponding pixel intensities in the defined regions of interest were statistically modeled using a Weibull probability density function from which parameters a (transparency) and ß (homogeneity) were derived. Results: The cornea in MFS showed significantly higher light reflectivity (overall cornea, a = 71 ± 17 arbitrary units (a.u.)) than in the control group (overall cornea, a = 59 ± 15 a.u.) (t test, P = 0.003). The a parameter was significantly higher in MFS eyes in all examined layers and regions (P 0.05). The difference in a did not correlate with ocular biometric properties (corneal thickness and curvature) or ectopia lentis (P> 0.05). Conclusions: The cornea in MFS shows significantly higher reflectivity than healthy controls with similar levels of homogeneity. Translational Relevance: The proposed methodology detects corneal reflectivity changes in MFS not available from regular slit-lamp examination

Cast Glance Near Infrared Imaging Observations of the Space Shuttle During Hypersonic Re-Entry

High resolution calibrated infrared imagery of the Space Shuttle was obtained during hypervelocity atmospheric entries of the STS-119, STS-125 and STS128 missions and has provided information on the distribution of surface temperature and the state of the airflow over the windward surface of the Orbiter during descent. This data collect was initiated by NASA s Hypersonic Thermodynamic Infrared Measurements (HYTHIRM) team and incorporated the use of air- and land-based optical assets to image the Shuttle during atmospheric re-entry. The HYTHIRM objective is to develop and implement a set of mission planning tools designed to establish confidence in the ability of an existing optical asset to reliably acquire, track and return global quantitative surface temperatures of the Shuttle during entry. On Space Shuttle Discovery s STS-119 mission, NASA flew a specially modified thermal protection system tile and instrumentation package to monitor heating effects from boundary layer transition during re-entry. On STS-119, the windward airflow on the port wing was deliberately disrupted by a four-inch wide and quarter-inch tall protuberance built into the modified tile. In coordination with this flight experiment, a US Navy NP-3D Orion aircraft was flown 28 nautical miles below Discovery and remotely monitored surface temperature of the Orbiter at Mach 8.4 using a long-range infrared optical package referred to as Cast Glance. Approximately two months later, the same Navy Cast Glance aircraft successfully monitored the surface temperatures of the Orbiter Atlantis traveling at approximately Mach 14.3 during its return from the successful Hubble repair mission. In contrast to Discovery, Atlantis was not part of the Boundary Layer Transition (BLT) flight experiment, thus the vehicle was not configured with a protuberance on the port wing. In September 2009, Cast Glance was again successful in capturing infrared imagery and monitoring the surface temperatures on Discovery s next flight, STS-128. Again, NASA flew a specially modified thermal protection system tile and instrumentation package to monitor heating effects from boundary layer transition during re-entry. During this mission, Cast Glance was able to image laminar and turbulent flow phenomenology optimizing data collection for Mach 14.7. The purpose of this paper is to describe key elements associated with STS-119/125/128 mission planning and execution from the perspective of the Cast Glance flight crew that obtained the imagery. The paper will emphasize a human element of experience, expertise and adaptability seamlessly coupled with Cast Glance system and sensor technology required to manually collect the required imagery. Specific topics will include a near infrared (NIR) camera upgrade that was implemented just prior to the missions, how pre-flight radiance modeling was utilized to optimize the IR sensor configuration, communications, the development of aircraft test support positions based upon Shuttle trajectory information, support to contingencies such as Shuttle one orbit wave-offs/west coast diversions and then the Cast Glance perspective during an actual Shuttle imaging mission

Speciation of vanadium in the dissolved, colloidal, and sediment phase under dynamic redox-conditions in a V contaminated soil treated and untreated with biochar

Vanadium is a redox-sensitive toxic element and can exist in a variety of oxidation states: −1, 0, +2, +3, +4, and +5. Vanadium (+5) is considered as a potentially dangerous pollutant. Biochar (BC) can be used to remediate soils contaminated with potential toxic elements (PTEs) including V. However, the efficiency of BC to immobilize V and its on speciation of V in the dissolved and colloidal phase and its mobilization and phytoavailability in the sediment phase under dynamic redox-conditions in highly contaminated soils under dynamic redox conditions has not been studied up to date. Thus, we have i) quantified the impact of pre-definite redox conditions on the speciation and release dynamics of V in the dissolved and colloidal phase as well as on the mobilization and phytoavailability of V in the soil sediments phase in a highly contaminated alkaline soil (CS) (non-treated) (pH = 7.44 and total V = 1,040 mg kg-1) collected from China and in the same soil treated with BC (CS+BC), and ii) assessed the impact of rice husk biochar as soil amendment on the same parameters. The impact of redox potential (EH), pH, dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), iron (Fe), manganese (Mn), and sulfate (SO42-) on speciation and release dynamics of V was also determined under dynamic redox conditions. In addition, the used biochar was characterized using scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDX) and nuclear magnetic resonance spectroscopy (NMR). The experiment was conducted in stepwise from moderate reducing (-30 mV in CS and -12 mV in CS+BC) to oxidizing (+218 mV in CS and +333 mV in CS+BC) soil conditions in different cycles using a highly sophisticated automated biogeochemical microcosm apparatus. Flooding of the CS and CS+BC caused significant changes of pH values which varied from 6.15 to 8.33 in the CS and from 5.14 to 7.91 in the CS+BC and the EH correlated negatively with pH. The dissolved concentrations of V varied from 15.2-46.4 mg L-1 in the CS to 14.9-50.2 mg L-1 in the CS+BC, while the colloidal concentrations of V varied from 39.5-49.9 mg L-1 in the CS to 31.8-50.2 mg L-1 in the CS+BC. Different redox cycles affected significantly the speciation and release dynamics of V in the dissolved and colloidal phase and its mobilization and phytoavailability in the sediment phase

Development and validation of a patient‐assessed gastroparesis symptom severity measure: the Gastroparesis Cardinal Symptom Index

SummaryBackground : Patient‐based symptom assessments are necessary to evaluate the effectiveness of medical treatments for gastroparesis.Aim : To summarize the development and measurement qualities of the Gastroparesis Cardinal Symptom Index (GCSI), a new measure of gastroparesis‐related symptoms.Methods : The GCSI was based on reviews of the medical literature, clinician interviews and patient focus groups. The measurement qualities (i.e. reliability, validity) of the GCSI were examined in 169 gastroparesis patients. Patients were recruited from seven clinical centres in the USA to participate in this observational study. Patients completed the GCSI, SF‐36 Health Survey and disability day questions at a baseline visit and again after 8 weeks. Clinicians independently rated the severity of the patients' symptoms, and both clinicians and patients rated the change in gastroparesis‐related symptoms over the 8‐week study.Results: The GCSI consists of three sub‐scales: post‐prandial fullness/early satiety, nausea/vomiting and bloating. The internal consistency reliability was 0.84 and the test–re‐test reliability was 0.76 for the GCSI total score. Significant relationships were observed between the clinician‐assessed symptom severity and the GCSI total score, and significant associations were found between the GCSI scores and SF‐36 physical and mental component summary scores and restricted activity and bed disability days. Patients with greater symptom severity, as rated by clinicians, reported greater symptom severity on the GCSI. The GCSI total scores were responsive to changes in overall gastroparesis symptoms as assessed by clinicians (P = 0.0002) and patients (P = 0.002).Conclusion: The findings of this study indicate that the GCSI is a reliable and valid instrument for measuring the symptom severity in patients with gastroparesis

Factors affecting metal mobilisation during oxidation of sulphidic, sandy wetland substrates

Most metals accumulate as sulphides under anoxic conditions in wetland substrates, reducing their bioavailability due to the solubility of metal sulphides. However, upon oxidation of these sulphides when the substrate is occasionally oxidised, metals can be released from the solid phase to the pore water or overlaying surface water. This release can be affected by the presence of carbonates, organic matter and clay. We compared changes of Cd, Cu and Zn mobility (CaCl2 extraction) during oxidation of a carbonate-rich and a carbonate-poor sulphidic, sandy wetland substrate. In addition, we studied how clay with low and high cation sorption capacity (bentonite and kaolinite, respectively) and organic matter (peat) can counteract Cd, Cu and Zn release during oxidation of both carbonate-rich and carbonate-poor sulphidic sediments. CaCl2-extractability of Cu, a measure for its availability, is low in both carbonate-poor and carbonate-rich substrates, whereas its variability is high. The availability of Cd and Zn is much higher and increases when peat is supplied to carbonate-poor substrates. A strong reduction of Cd and Zn extractability is observed when clay is added to carbonate-poor substrates. This reduction depends on the clay type. Most observations could be explained taking into account pH differences between treatments, with kaolinite resulting in a lower pH in comparison to bentonite. These pH differences affect the presence and characteristics of dissolved organic carbon and the metal speciation, which in turns affects the interaction of metals with the solid soil phase. In carbonate-rich substrates, Cd and Zn availability is lower and the effects of peat and clay amendment are less clear. The latter can also be attributed to the high pH and lack of pH differences between treatments

A hyperparasite affects the population dynamics of a wild plant pathogen

Peer reviewe

Lack of Relationship Between Chronic Upper Abdominal Symptoms and Gastric Function in Functional Dyspepsia

To determine the relationship between gastric function and upper abdominal sensations we studied sixty FD patients (43 female). All patients underwent three gastric function tests: 13C octanoic gastric emptying test, three-dimensional ultrasonography (proximal and distal gastric volume), and the nutrient drink test. Upper abdominal sensations experienced in daily life were scored using questionnaires. Impaired proximal gastric relaxation (23%) and a delayed gastric emptying (33%) are highly prevalent in FD patients; however, only a small overlap exists between the two pathophysiologic disorders (5%). No relationship was found between chronic upper abdominal symptoms and gastric function (proximal gastric relaxation, gastric emptying rate, or drinking capacity) (all P > 0.01). Proximal gastric relaxation or gastric emptying rate had no effect on maximum drinking capacity (P > 0.01). The lack of relationship between chronic upper abdominal sensations and gastric function questions the role of these pathophysiologic mechanisms in the generation of symptoms