Percutaneous Anorectoplasty (PARP)-An Adaptable, Minimal-Invasive Technique for Anorectal Malformation Repair

Background: Anorectal malformations comprise a broad spectrum of disease. We developed a percutaneous anorectoplasty (PARP) technique as a minimal-invasive option for repair of amenable types of lesions. Methods: Patients who underwent PARP at five institutions from 2008 through 2021 were retrospectively analyzed. Demographic information, details of the operative procedure, and perioperative complications and outcomes were collected. Results: A total of 10 patients underwent the PARP procedure during the study interval. Patients either had low perineal malformations or no appreciable fistula. Most procedures were guided by ultrasound, fluoroscopy, or endoscopy. Median age at PARP was 3 days (range 1 to 311) days;eight patients were male. Only one intraoperative complication occurred, prompting conversion to posterior sagittal anorectoplasty. Functional outcomes in most children were highly satisfactory in terms of continence and functionality. Conclusions: The PARP technique is an excellent minimal-invasive alternative for boys born with perineal fistulae, as well as patients of both sexes without fistulae. The optimal type of guidance (ultrasound, fluoroscopy, or endoscopy) depends on the anatomy of the lesion and the presence of a colostomy at the time of repair

Air-sea gas transfer : its dependence on wind stress, small-scale roughness, and surface films

Author Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 109 (2004): C08S17, doi:10.1029/2003JC002131.The influence of wind stress, small-scale waves, and surface films on air-sea gas exchange at low to moderate wind speeds (<10 m s−1) is examined. Coincident observations of wind stress, heat transfer velocity, surface wave slope, and surface film enrichments were made in coastal and offshore waters south of Cape Cod, New England, in July 1997 as part of the NSF-CoOP Coastal Air-Sea Chemical Fluxes study. Gas transfer velocities have been extrapolated from aqueous heat transfer velocities derived from infrared imagery and direct covariance and bulk heat flux estimates. Gas transfer velocity is found to follow a quadratic relationship with wind speed, which accounts for ~75–77% of the variance but which overpredicts transfer velocity in the presence of surface films. The dependence on wind stress as represented by the friction velocity is also nonlinear, reflecting a wave field-dependent transition between limiting transport regimes. In contrast, the dependence on mean square slope computed for the wave number range of 40–800 rad m−1 is found to be linear and in agreement with results from previous laboratory wind wave studies. The slope spectrum of the small-scale waves and the gas transfer velocity are attenuated in the presence of surface films. Observations over large-scale gradients of biological productivity and dissolved organic matter show that the reduction in slope and transfer velocity are more clearly correlated with surface film enrichments than with bulk organic matter concentrations. The mean square slope parameterization explains ~89–95% of the observed variance in the data and does not overpredict transfer velocities where films are present. While the specific relationships between gas transfer velocity and wind speed or mean square slope vary slightly with the choice of Schmidt number exponent used to scale the heat transfer velocities to gas transfer velocities, the correlation of heat or gas transfer velocity with mean square slope is consistently better than with wind speed.Funding for this work was provided by the NSF Coastal Ocean Processes (CoOP) program (OCE-9410534, OCE- 9711285 (WHOI) and OCE-9409222, OCE-9711391(URI)). Additional support for data analysis was provided by NASA (NAGW-2431, JPL Contract 961425). Partial funding was also provided by the German Science Foundation (DFG) through the DFG research unit FOR240: Image Sequence Analysis to Investigate Dynamic Processes

Impact of bulk weight on drying behaviour and hop quality after drying

Hops are a key ingredient for beer brewing due to their role in the creation of the foam characteristics, bitterness of the beers and aroma. Whilst in the past foam and bitterness were the key characteristics sought by the market, the last decade has seen a steep increase in demand of aroma hops for the production of crafts beers. Color of the final product plays a major role in quality perception of traders and brewers. Therefore, color changes were investigated to estimate the impact of bulk weight and thus drying time and conditions on the upper surface of the bulk. A calibrated imaging system consisting of a CCD camera and illumination was integrated into the dryer. Further, changes of and ß acid contents were investigated. Hops of the variety Mandarina Bavaria were dried at 65°C and an air velocity of 0.35 m/s. Bulk weights investigated were 12, 20 and 40 kg/m² respectively. Drying times were 105, 135, and 195 min. Drying characteristics showed a unique development which very likely is due to the distinct physiology of hop cones (string, bracteole, bract, lupilin glands). Color changes depended strongly on the bulk weight and resulting bulk thickness whilst a and ß acid contents were not affected by the drying conditions. The research presented showed that air mass flow in relation to the mass of water to be removed is critical for the quality of the product as well as the processing time required

Measurement of hop moisture content and chromaticity during drying with VNIR hyperspectral imaging

The drying of hops is a crucial post harvesting stage in the production of beer. If hops are not dried to below a specific moisture content they will spoil prior to being processed into pellets for beer production. Further to this, drying of hops is usually undertaken by farmers themselves, and with a single harvest per year the drying operation is of great economic importance for their survival. The monitoring of moisture content is usually undertaken through moisture and humidity sensors placed within the hops themselves. However this method leads to the sampling of moisture content in specific spots, and as such relies upon drying uniformity. Furthermore the moisture content of the hops at the input stage varies greatly with environmental conditions. Optical methods with 2D sensors offer the opportunity to monitor moisture content changes across the entire drying area. With hyperspectral imaging allowing investigations to uncover the most important wavelengths related to moisture content. To investigate this Mandarina Bavaria hops were imaged during the drying process in-situ using a hyperspectral camera (Specim PFD-V10E) across the 400-1000nm region. Drying was undertaken at two temperatures (65, 70°C), with three different bulk weights (12, 20 and 40 kg/m²) and at two air speeds (0.35 and 0.50-0.35m/s). This was to introduce variation into the model to allow fully characterisation of spectral changes of hops during drying. Investigations have shown that a simple optical system using a small number of wavelengths can be used to estimate hop moisture content and chromaticity

Ion association and solvation of perchlorate salts in N,N-dimethylformamide and N,N-dimethylacetamide

The results of dielec. relaxation expts. on solns. of LiClO4, NaClO4 and Bu4NClO4 in N,N-dimethylformamide (DMF), and N,N-dimethylacetamide (DMA), performed at 25 °C in the frequency range 0.2 ≤ ν/GHz ≤ 89 are presented. For all electrolytes, a solute relaxation process due to ion pairs is obsd. in addn. to the solvent relaxation. The alkali salts form predominantly solvent-shared ion pairs in DMF and DMA, whereas contact ion pairs are obsd. for Bu4NClO4. In all cases, the rate of ion-pair formation is nearly diffusion-controlled. Effective solvation nos. were deduced from the solvent dispersion amplitude. Data suggest that the anion-solvent interactions are weak, whereas the alkali ions form a well-defined primary solvation shell. Interestingly, irrotational bonding of solvent mols. by Bu4N+ is obsd., possibly due to steric interactions

Dielectric relaxation spectroscopy of electrolyte solutions. Recent developments and prospects

A review with 59 refs.; exemplified by recent temp.-dependent measurements from the authors' lab. it is shown that precise complex permittivity spectra obtained by the use of time domain and frequency domain methods in the mega- to gigahertz range yield specific information on solvent dynamics as well as on ion-solvation and ion-assocn. phenomena not available so far

Influence of pre‐drying storage time on essential oil components in dried hops (Humulus lupulus L.)

BACKGROUND: It is well known that duration of pre-drying storage impacts on hop quality. However, little knowledge existsregarding its actual effects on valuable hop components. To investigate these effects, fresh hop cones were stored for 5 or24 h and dried for 210 min at 65 °C thereafter. Furthermore, to understand the effect of freezing hop cones on the essentialoil content, both fresh and stored samples were frozen before and after drying. RESULTS: The results from gas chromatography analysis show an increase in linalool, -caryophyllene, humulene, geraniol con-tent and decrease in myrcene content dependent on the period of storage. Total colour difference ∆E values of 4.61 and 5.27were obtained for fresh and stored hops respectively, indicating discoloration of hops during storage. Modelling of moisturecurves revealed the Wang and Singh model to be suitable, with R2adjvalues of 0.978 and 0.989 and root-mean-square errorvalues of 0.037 and 0.019 for fresh and stored hops respectively. CONCLUSION: The results from this study provide an in-depth understanding on the changes occurring within the hop conesboth during storage and drying and will further help hop processors optimize their storage times

Impact of Process Parameters and Bulk Properties on Quality of Dried Hops

Hops are critical to the brewing industry. In commercial hop drying, a large bulk of hops is dried in multistage kilns for several hours. This affects the drying behavior and alters the amount and chemical composition of the hop oils. To understand these changes, hops of the var. Hallertauer Tradition were dried in bulks of 15, 25 and 35 kg/m&sup2; at 60 &deg;C and 0.35 m/s. Additionally, bulks of 25 kg/m&sup2; were also dried at 65 &deg;C and 0.45 m/s to assess the effect of change in temperature and velocity, respectively. The results obtained show that bulk weights significantly influence the drying behavior. Classification based on the cone size reveals 45.4% medium cones, 41.2% small cones and 8.6% large cones. The highest &Delta;E value of 6.3 and specific energy consumption (113,476 kJ/kgH2O) were observed for the 15 kg/m&sup2; bulk. Increasing the temperature from 60 &deg;C to 65 &deg;C increased the oil yield losses by about 7% and myrcene losses by 22%. The results obtained show that it is important to define and consider optimum bulk and process parameters, to optimize the hop drying process to improve the process efficiency as well the product quality

Impact of Process Parameters and Bulk Properties on Quality of Dried Hops

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