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The effective monitoring of hydraulic fracturing in unconventional oil and gas production requires tools to quantify elastic property variations even in the absence of microseismic activity. To track the subtle time-lapse variations in reservoir properties during such activities, monitoring techniques with high repeatability and high resolution, spatially and temporally, are required. Distributed acoustic sensing (DAS) is a rapidly maturing fiber-optic technology for low-cost, permanent, high density, in-well monitoring. Surface orbital vibrators (SOVs) are inexpensive fixed rotary seismic sources that offer the opportunity to frequently interrogate the subsurface with energies comparable to vibroseis sources. We have evaluated a field vertical seismic profile test, conducted in the Eagle Ford play, pairing an SOV source recorded by DAS behind casing in a deviated well to better evaluate the potential of the technology set for unconventional reservoir monitoring. We determine the data processing workflow for reservoir monitoring using the SOV-DAS system. We analyze the data characteristics of the SOV-DAS system, including the signal-to-noise ratio characteristics and source repeatability. High-quality P- and S-wave reflections, as well as mode conversions, are visible in the vertical section. In addition, clear P-P reflections are also observable along the horizontal well sections. Time shifts with a mean value of 10 μs between different data sets demonstrate the high repeatability for the semipermanent SOV source, which is crucial for time-lapse analysis. We also apply reflection imaging on P and S to reveal reflection depths. In a first-of-its-kind deployment, we implemented a rotating SOV with a slewing bearing and discuss the possibility to optimize S-wave construction along the horizontal well with specific SOV orientation directions. Our preliminary results indicate that the combination of repeatable surface sources such as SOVs with DAS has significant potential for providing a low-cost approach for high-resolution seismic monitoring of unconventional reservoirs.

This case report presents a lipofibromatous hamartoma of the median nerve in a 31-year-old man who presents local deformity and a sensory deficit in the nerve territory. The tumor was evaluated with magnetic resonance, computed tomography, and plain film radiography, studying the pathognomonic findings of this tumor. The patient did not want surgical treatment because of prior surgical sequelae. A prior surgical biopsy was reported as a peripheral nerve with normal axonal fascicles surrounded by abundant fibroadipose tissue. This tumor has a low incidence with less than 180 cases reported in the literature., {"references":["Al-Jabri T, Garg S, Mani GV. Lipofibromatous hamartoma of the median nerve. J Orthop Surg Res. 2010;5:71. doi: 10.1186/1749-799X-5-71.","Toms AP, Anastakis D, Bleakney RR, Marshall TJ. Lipofibromatous hamartoma of the upper extremity: a review of the radiologic findings for 15 patients. AJR Am J Roentgenol. 2006;186: 805-11. doi: 10.2214/AJR.04.1717.","Tahiri Y, Xu L, Kanevsky J, Luc M. Lipofibromatous hamartoma of the median nerve: a comprehensive review and systematic approach to evaluation, diagnosis, and treatment. J Hand Surg Am. 2013;38:2055-67. doi: 10.1016/j.jhsa.2013.03.022.","Nilsson J, Sandberg K, Søe Nielsen N, Dahlin LB. Magnetic resonance imaging of peripheral nerve tumours in the upper extremity. Scand J Plast Reconstr Surg Hand Surg. 2009;43:153-9. doi: 10.1080/02844310902734572.","Nardella D, Sohawon S, Carlier A. Lipofibromatous hamartoma of the median nerve. Three case reports. J Plast Reconstr Aesthet Surg. 2009;62 :e314-7. doi: 10.1016/j.bjps.2007.11.061.","Cavallaro MC, Taylor JA, Gorman JD, Haghighi P, Resnick D. Imaging findings in a patient with fibrolipomatous hamartoma of the median nerve. AJR Am J Roentgenol. 1993;161:837-8. doi: 10.2214/ajr.161.4.8372770.","Kara M, Ozcakar L, Ekiz T, Yalçın E, Tiftik T, Akyüz M. Fibrolipomatous hamartoma of the median nerve: comparison of magnetic resonance imaging and ultrasound. PM R 2013;5:805-6. doi: 10.1016/j.pmrj.2013.03.026.","Okechi H, Dimostheni A, Kerscher SR, Gugel I, Bevot A, Schaefer JF, et al. Fibrolipomatous hamartomas of the median nerve in infancy and early childhood-imaging hallmarks, symptomatology, and treatment. Eur J Pediatr. 2018; 177 :567-73. doi: 10.1007/s00431-018-3100-7.","Giuliano V, Outwater EK, Mitchell DG, Burke MA. Median nerve hamartoma: MR imaging using chemical shift techniques. Magn Reson Imaging. 1997;15:1091-4. doi: 10.1016/s0730-725x(97)00155-0."]}

The acromial and coracoid process morphology is of clinical relevance due to associations with functional limitations and shoulder pathology. Our objective was to describe the anatomical characteristics of the acromial and coracoid process using computed tomography (CT). Descriptive, observational, transversal and retrospective study. A total of 155 CT of patients without shoulder pathology, of both genders, and indistinct age were evaluated and grouped by age: Group 1 40 years. The following parameters were evaluated: Acromial type (AcT), vertical coracoid distance (VCD), acromial tilt (AT), acromial projection (AP), critical shoulder angle (CSA), type of the subcoracoid outlet (TSO), and the area of the subcoracoid outlet (ASO). Statistically significant differences were found between men and women for VCD (14.44 ± 4.79 vs. 11.76 ± 4.00 mm; p

The effectiveness of surfactants to improve oil recovery in unconventional oil reservoirs through wettability alteration and enhancement of spontaneous imbibition has been extensively studied. However, very few simulation studies have considered the impact of complex fracture networks on the wettability alteration due to the difficulty in handling the connection between fractures and matrix. Non-uniform fracture networks are difficult to represent using traditional discrete fracture models and local grid refinement (LGR). In this study, we used the Embedded Discrete Fracture Model (EDFM) method to simulate wettability alteration in reservoirs with complex fracture networks. In EDFM, the reservoir is discretized with structured grids, and additional grids are created to represent the fractures. Each fracture plane is that is physically embedded inside a matrix grid is discretized by the cell boundaries, and transport coefficients are calculated for those additional grids. We verified our EDFM model against LGR in both oil wet and water wet conditions for relatively uniform geometries, observing good matches in well productivities and pressure responses. Then we performed a series of numerical sensitivity studies to demonstrate the impact of natural fracture networks on the wettability alteration. Our results show that fracture density, sets of fractures, and fracture conductivity significantly affect the well productivity. The matrix permeability also has similar effects. We modified the wettability condition of the activated fracture grids and matrix grids around fractures from oil-wet to water-wet. The impacts of fractures and permeability were greatly amplified in changing from oil-wet to water-wet systems, as occurs when surfactant is added to injected frac water. This study improves our capability in the area of modeling complex fracture networks, and provides meaningful guidance for enhanced oil recovery in shale reservoirs when designing a surfactant injection strategy.

Amyand’s hernia is an uncommon form of inguinal hernia. It represents

Background Mycetoma is a chronic, localized infection caused by fungi and bacteria. It usually affects the skin, subcutaneous tissue, and bone of exposed areas with deformity of the affected limb, ulcers, and fistula; however, pain is not severe, therefore the patient comes late to hospital for care. Objective To establish the diagnosis of mycetoma in the foot by imaging and identify the principal radiological signs. Materials and methods Six patients with foot mycetoma were evaluated with plain x-ray, ultrasound, and magnetic resonance (MR) after confirming the diagnosis by histopathology and culture. Results All patients presented the MR "dot-in-circle" sign; four presented "punched out" bone lesions on plain x-ray. The six patients had fistulas, ulceration, a seropurulent exudate, edema, and a foot deformity. Four patients had N. brasiliensis infection with positive anti-Nocardia IgG antibodies, and only half presented bone lesions. Conclusion Characteristic findings were foot deformity, edema, bone lesions, ulcers, fistulas and the presence of the "dot-in-circle" sign. We recommend a comprehensive study of patients with plain x-ray and MR.

IntroductionDonor sites of split-thickness skin grafts (STSGs) are painful and limit patient rehabilitation. We conducted this study to assess the efficacy of a non-adherent polyurethane dressing in reducing pain and its effect on the epithelialization rate of donor sites of STSGs.MethodsFifteen patients requiring an STSG were included. In 10 patients the donor sites were randomly divided into two halves and covered with either a non-adherent polyurethane dressing or a standard non-adherent gauze. In five patients with bilateral donor sites, one side was covered with the non-adherent polyurethane dressing and the other with non-adherent gauze. The pain was assessed with a visual analog scale and epithelialization was also assessed, calculating non-epithelialized areas with image software by a blinded surgeon. Epithelialization of the wounds covered with the non-adherent polyurethane dressing was assessed at day 8 and 10 and those with non-adherent gauze at day 10.ResultsPostoperative pain significantly decreased with the non-adherent polyurethane dressing during the length of the study (6.07±1.46 vs. 1.72±1.6) and at each time point (p

To gain understanding of the mechanisms and rock properties which dominate fracture conductivity generation and decline, fracture conductivity behavior was investigated in several shale reservoirs in the laboratory to identify the main parameters that control the fracture conductivity. The comprehensive study investigated the conductivity behaviors of four shale plays, the Barnett, Fayetteville, Marcellus and Eagle Ford, by testing fracture conductivity as a function of closure stress using collected outcrop rock samples. Conductivity of fractured rock samples are measured using a modified API RP 61 procedure. In addition to conductivity, a plethora of rock properties such as Young's modulus, Poisson's ratio, Brinell hardness, rock brittleness, and mineralogy are measured corresponding to each conductivity test sample. Other parameters considered in this study include proppant mesh size, proppant concentration, and fracture topography to see the resulting impact on conductivity. With all measurements, a multivariate analysis is carried out with the goal of seeking a correlation between fracture conductivity and the influential rock properties and treatment parameters. All results are cross-compared to identify similarities and differences between formations as well as the most important parameters influencing fracture conductivity relative to each formation. The results indicate a positive trend between both Brinell hardness and Young's Modulus with fracture conductivity. Increased fracture face surface roughness is also found to have an overall decrease in conductivity in propped fractures. The influential parameters are different for different shale plays. Some parameters are more important in one formation but less influential in others. The observations are integrated into a preliminary simple correlation for conductivity behavior. The observations and results from this study clarify the similarity and differences in varying shale plays.

OBJECTIVE. The purpose of this study was to assess esophageal damage in patients with recessive dystrophic epidermolysis bullosa (RDEB) with or without dysphagia. SUBJECTS AND METHODS. Fourteen patients with either severe generalized or another generalized form of RDEB recruited through a research and support foundation were evaluated for obstructive esophageal lesions by means of barium esophagography. RESULTS. All patients, even those without dysphagia, had at least one stenosis; five patients had two stenoses. Stenotic lesions occurred most often (74%) in the upper third of the esophagus. CONCLUSION. Esophageal stenosis is a common complication in patients with RDEB, even when they do not have dysphagia. We recommend regular esophagographic examinations of all patients with RDEB.

Sand erosion may cause severe damage of blades in wind turbine and helicopter blades as well as many surface compo- nents of airplanes. In this study, thin nanopapers made of carbon nanofibers (CNFs) are used to enhance the resistance of solid parti- cle erosion of glass fiber (GF)/wind epoxy composites. Finite element computer simulations are used to elucidate the underlying mechanisms. The much higher particle erosion resistance of nanopapers compared to GF-reinforced epoxy composites is attributed to the high strength of CNFs and their nanoscale structure. The excellent performance in particle erosion resistance makes the CNF- based nanopaper a prospective protective coating material for the turbine blades in the wind energy industry. V C 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 000: 000-000, 2012

In this article, a new manufacturing method was used to prepare the hybrid composite, wherein carbon nanofibers were sprayed and bonded onto continuous fiber mats instead of pre-mixing them in the polymer resin. The effect of carbon nanofibers on the mold filling characteristics in a vacuum assisted resin transfer molding system was investigated. A simple one-dimensional flow model was used to correlate the permeability and porosity to the mold filling time. It was found that the dispersion and loading of the carbon nanofibers affected the permeability and porosity of the reinforcement system, and hence the mold filling time.

Polyaniline (PANI) “nanograss” was grown on carbon nanofibers (CNFs). The cure behavior of an epoxy resin with and without unmodified CNFs or PANI modified CNFs was studied by means of non-isothermal and isothermal differential scanning calorimetry (DSC). CNFs accelerated the reaction of epoxy and diamine. PANI surface modification further increased the reaction rate and the extent of reaction. An autocatalytic cure kinetic model was used to fit the reaction curves. It was found that activation energies of the epoxy reaction decreased in the presence of CNFs and PANI modified CNFs. The observed catalytic effect of CNF and PANI surface coating can be very useful for low temperature cure of large epoxy composite products. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Summary Purpose To determine the effectiveness of three different combinations for the “loading phase” in the treatment of diabetic macular edema (DME), using bevacizumab (BVZ), triamcinolone (TCL) and subthreshold macular photocoagulation (SMPC). Methods Experimental, longitudinal, prospective, comparative and blind. Patients were randomly assigned to three treatment branches: Group 1: BVZ + SMPC (12 eyes), Group 2: SMPC + BVZ + TCL (7 eyes), Group 3: BVZ + TCL (11 eyes). Treatment with BVZ and TCL was given every 4 weeks for 3 months, SMPC was applied once at the beginning of treatment. Initial and final measurements of best corrected visual acuity (BCVA), central macular thickness (CMT) and intraocular pressure (IOP) were tested. Results The improvement in BCVA and the reduction in CMT was statistically superior in group of BVZ + SMPCwhen compared to the other groups. There were no differences in IOP. Conclusions Combined therapies in the “loading phase”are a good option when treating DME. Although the group with BVZ + SMPC obtained the best results, further studies with longer follow-up and a higher number of participants to establish this combined therapy as the first treatment option are required.