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Introduction Dupuytren’s contracture is a connective tissue disease characterized by an abnormal proliferation of collagen in the palm and fingers, which leads to a decline in hand function because of progressive joint flexion. In addition to surgical and percutaneous interventions, collagenase clostridium histolyticum (CCH, trade name Xiaflex) is an intralesional enzymatic treatment for adults with palpable cords. The objectives of this study are to evaluate factors predictive of recurrence following treatment with CCH and to review the outcomes of repeat treatments with CCH for recurrent contracture. Materials and Methods An institutional review board–approved retrospective chart review was conducted for patients between 2010 and 2017 who received CCH injections for Dupuytren’s contracture at a Veterans Affairs hospital. Demographics, comorbidities, affected finger and joint, pre/posttreatment contracture, time to recurrence, and treatment of recurrence were recorded. Successful treatment was defined as contracture ≤5° following CCH, and improvement was defined as ≥20° reduction from baseline contracture. Study cohorts were followed after their secondary treatment, and time to recurrence was recorded and plotted using a Kaplan–Meier curve. A Cox proportional hazards model was used to compare treatment group risk factors for recurrence with a P-value less than .05 defined as statistical significance. Results Of 174 injections performed for the correction of flexion deformities in 109 patients, 70% (121) were successfully treated with CCH, and an additional 20% (35) had improvement. There was a recurrence of contractures in 43 joints (25%). Of these, 16 contractures were treated with repeat CCH, whereas another 16 underwent limited fasciectomy. In total, 75% (12 of 16) of the repeat CCH group and 75% of the fasciectomy group were successfully treated. Pre-injection contracture of ≥25° was found to be predictive of recurrence (P Conclusions Initial treatment of contracture with CCH had a 70% success rate with 25% recurrence during the study period. Compared with limited fasciectomy, CCH had decreased efficacy. Based on the findings of this study, we believe that the treatment of primary and/or recurrent Dupuytren’s contracture with CCH is a safe and less invasive alternative to fasciectomy in the era of telemedicine. CCH treatment requires no suture removal, which allows the ability to assess motion virtually, and the potential consequences of CCH treatment such as skin tears can be assessed and managed conservatively. In the veteran and active duty population, CCH can facilitate faster recovery and return to service. Strengths of this study include a large series of veteran populations with longitudinal follow-up to determine treatment efficacy for primary Dupuytren’s contracture and recurrence. Limitations include a smaller sample size compared to previous trials, a lack of standardized follow-up, and the retrospective nature of our study that prohibits randomization to compare outcomes between CCH treatment and fasciectomy efficacy over time. Directions for future research include stratification of patients by joint and specific digit involvement as well as comparison with percutaneous needle fasciotomy, another minimally invasive technique that could benefit the veteran population at increased risk for developing Dupuytren’s disease.

Targeted muscle reinnervation (TMR) has been shown to improve phantom and neuropathic pain in both the acute and chronic amputee population. Through rerouting of major peripheral nerves into a newly denervated muscle, TMR harnesses the plasticity of the brain, helping to revert the sensory cortex back toward the preinsult state, effectively reducing pain. We highlight a unique case of an above-elbow amputee for sarcoma who was initially treated with successful transhumeral TMR. Following inadvertent nerve biopsy of a TMR coaptation site, his pain returned, and he was unable to don his prosthetic. Revision of his TMR to a more proximal level was performed, providing improved pain and function of the amputated arm. This is the first report to highlight the concept of secondary neuroplasticity and successful proximal TMR revision in the setting of multiple insults to the same extremity.

Highlights • Serratia marcescens is gram-negative facultative anaerobic bacillus. • S. marcescens is responsible for a small percentage of hospital-acquired infections. • S. marcescens infection usually occurs in outbreaks. • This case describes a rare chronic S. marcescens sternal infection., Introduction Serratia marcescens is a facultative anaerobic bacillus that very rarely causes sternal infections. We describe a sternal abscess resulting from chronic S. marcescens infection that presented 13 years after coronary artery bypass graft surgery (CABG). Presentation of case A 71-year-old diabetic man presented 13 years after CABG with a new distal sternal “mass” that intermittently drained purulent fluid. He was treated with oral antibiotics, but the symptoms persisted. Exploration revealed an abscess extending to the sternal body. A non-absorbable braided suture and a sternal wire were removed, but a sinus tract remained despite further antibiotics and conservative care. Subsequent computed tomography and bone scintigraphy revealed a substernal soft tissue density with bone involvement. An abscess cavity was excised from the substernal anterior mediastinum. Another non-absorbable braided suture was removed. Cultures grew carbapenem-resistant S. marcescens. Discussion Nosocomial or hospital-associated clusters of S. marcescens infection are known, but isolated infections seldom occur. S. marcescens infections in cardiac surgery patients are unusual. Only a single report described a chronic sternal infection resulting from S. marcescens that was identified 15 years after an initial episode caused by the same organism in a heart transplant recipient who was immunocompromised. Diabetes and non-absorbable braided sutures placed for hemostasis at the wire sites were probably contributing factors to our patient’s chronic infection. Conclusion This report described the presentation and treatment of a chronic S. marcescens sternal abscess that occurred 13 years after CABG. Chronic sternal infections due to this organism in cardiac surgery patients are exceeding rare.

Background Cosmetic surgery tourism is increasing exponentially. Patients seek cosmetic procedures within the United States and abroad, lured by lower cost procedures, shorter waiting lists, and affordable airfare and hotel accommodations. Unfortunately, operations are often performed by non–board-certified plastic surgeons, sometimes not even by plastic surgeons. Preoperative counseling, frequently limited to a video-chat with an office secretary, provides inadequate discussion regarding potential complications. Postoperative care is careless and rarely involves the operating surgeon. Complications are frequent, with management falling into the hands of plastic surgeons unfamiliar with the patient’s care. Furthermore, the physician, rather than the patient or hospital, faces the largest cost burden. Objectives The authors sought to explore their institution’s experience treating complications of cosmetic tourism and investigate associated costs. Methods The retrospective review of 16 patients treated for complications related to cosmetic surgery tourism plus cost analysis revealed a substantial discrepancy between money saved by undergoing surgery abroad and massive costs accrued to treat surgical complications. Results The most common complication was infection, often requiring surgery or IV antibiotics on discharge. Mean cost per patient was $26,657.19, ranging from $392 (single outpatient visit) to $154,700.79 (prolonged admission and surgery). Overall, the hospital retained 63% of billed charges, while physicians retained only 9%. The greatest amount paid by any single patient was $2635.00 by a patient with private insurance. Conclusions Cosmetic tourism has severe medical repercussions for patients and complications that burden hospitals, physicians, and the US medical system. Physicians treating the complications suffer the greatest financial loss. Level of Evidence: 4

Background: Proximally based, pedicled flexor carpi ulnaris (FCU) muscle flap has been described previously for soft tissue coverage of the proximal forearm and elbow. No studies have been done on the distal muscular perforators and its use as a distally based flap. Methods: Ten fresh-frozen cadaveric dissections were done. Specimens were injected with latex to facilitate identification of the perforators. Distal muscular perforators were dissected and distances of the pedicles from the distal wrist crease and ulnar styloid were measured and recorded. A clinical case is also presented where a distally based FCU muscle flap was used for coverage in a patient with median nerve neuroma. Results: A distal muscular perforator and a second more proximal perforator were identified in all specimens. The average distance from the most distal muscular perforator to the ulnar styloid was 3.0 cm. The average distance to the wrist crease was 4.6 cm. The more proximal perforators had an average distance to the ulnar styloid and wrist crease of 7.3 cm and 8.8 cm, respectively. At 7 months post-op, the patient who underwent median nerve neurolysis and coverage with pedicled FCU flap had much improved sensation, with complete resolution of pain and tingling, and without any functional deficits. Conclusions: The use of a distally based FCU muscle flap is a good option for soft tissue coverage of the distal forearm, wrist, and hand. The distal muscular perforators from the ulnar artery exhibit a relatively consistent anatomy.

Background: Cubital tunnel syndrome is a common compressive neuropathy of the upper extremity. The anconeus epitrochlearis muscle is an unusual but occasional contributor. We review our experience with this anomalous muscle in elbows with cubital tunnel syndrome. Methods: We retrospectively reviewed charts of 13 patients noted to have an anconeus epitrochlearis muscle associated with cubital tunnel syndrome. Results: Ten patients had unilateral ulnar neuropathy supported by nerve conduction studies. Three had bilateral cubital tunnel syndrome symptoms with 1 of those having normal nerve conduction studies for both elbows. Eight elbows were treated with myotomy of the anconeus epitrochlearis muscle and submuscular transposition of the ulnar nerve. The other 8 elbows were treated with myotomy of the anconeus epitrochlearis muscle and in situ decompression of the ulnar nerve only. All but 1 patient had either clinical resolution or improvement of symptoms at follow-up ranging from 2 weeks to 1 year after surgery. The 1 patient who had persistent symptoms had received myotomy and in situ decompression of the ulnar nerve only. Conclusions: An anomalous anconeus epitrochlearis occasionally results in compression of the ulnar nerve but is usually an incidental finding. Its contribution to compression neuropathy can be tested intraoperatively by passively ranging the elbow while observing the change in vector and tension of its muscle fibers over the ulnar nerve. Regardless of findings, we recommend myotomy of the muscle and in situ decompression of the ulnar nerve. Submuscular transposition of the ulnar nerve may be necessary if there is subluxation.

Heterotopic ossification (HO) is widely recognized as a common occurrence among patients suffering from traumatic spinal cord injuries (SCI). The exact etiology of HO formation remains unknown. Published medical and surgical management strategies are often plagued with questionable effectiveness and frequent complications. There are minimal publications regarding the management strategies of HO in SCI patients as it pertains to plastic surgery. We present a case series of patients treated at our institution who underwent treatment for pressure ulcers with underlying HO to highlight the vast spectrum of clinical phenotypes present in this population. The pathophysiology, diagnostic tools, methods of prevention, and surgical management of HO are discussed here. We believe that there are two clinically relevant patterns of HO in SCI patients. A neurogenic process that occurs early after injury is usually bilateral and involves uninjured hip joints. Pressure sores that occur are related to poor joint mobility and subsequent development of pressure points. An infection-driven process in which HO development is associated with either pressure sores or septic hip joints is generally unilateral and not always associated with hip contractures. They present different challenges and reconstructive options to plastic surgeons. Although complications such as infection and HO recurrence are common, the functional and psychological benefits of restoring hip flexion are usually worthwhile.

Background The shape of the deep cervical structures is the shape of an aesthetic neck. With age, changes can obstruct visualization of that shape. Achieving a youthful contour requires removal of excess skin and fat but also control of the platysma to allow skin to redrape like a blanket over an underlying framework. The authors' technique makes the platysma part of the deep cervical structures whose shape underlies an attractive neck and allows the skin to redrape to that contour. Methods To make the platysma conform closely to the deep cervical structures and allow the skin to show that new form, the authors developed a procedure that includes removal of excess fat, attaching the platysma to the hyoid fascia, approximating the edges of the platysma above and below that suture, and wide undermining of skin to allow it to re-drape naturally over those deeper structures. Results Over 7 years, 110 patients underwent aesthetic facial surgery that included hyoid suspension of the platysma. One patient had recurrence of platysmal bands after failure of the key suture. Complications included hematoma in three patients and submental seromas in three patients, but no permanent nerve injury, no skin loss from vascular compromise, no reported changes in vocal resonance, and no complaints of difficulty swallowing. Conclusions This method allows the skin to redrape over a youthful framework and produces reliable aesthetic and long lasting results. It is a simple, reproducible, teachable technique that enables surgeons to achieve results previously difficult to obtain in a single operation. Clinical question/level of evidence Therapeutic, IV.

Background Insidious cumulative brain injury from motor vehicle-induced whole-body vibration (MV-WBV) has not yet been studied. The objective of the present study is to validate whether whole-body vibration for long periods causes cumulative brain injury and impairment of the cerebral function. We also explored a preventive method for MV-WBV injury. Methods A study simulating whole-body vibration was conducted in 72 male Sprague-Dawley rats divided into 9 groups (N = 8): (1) 2-week normal control; (2) 2-week sham control (in the tube without vibration); (3) 2-week vibration (exposed to whole-body vibration at 30 Hz and .5 G acceleration for 4 hours/day, 5 days/week for 2 weeks; vibration parameters in the present study are similar to the most common driving conditions); (4) 4-week sham control; (5) 4-week vibration; (6) 4-week vibration with human apolipoprotein A-I molecule mimetic (4F)-preconditioning; (7) 8-week sham control; (8) 8-week vibration; and (9) 8-week 4F-preconditioning group. All the rats were evaluated by behavioral, physiological, and histological studies of the brain. Results Brain injury from vibration is a cumulative process starting with cerebral vasoconstriction, squeezing of the endothelial cells, increased free radicals, decreased nitric oxide, insufficient blood supply to the brain, and repeated reperfusion injury to brain neurons. In the 8-week vibration group, which indicated chronic brain edema, shrunken neuron numbers increased and whole neurons atrophied, which strongly correlated with neural functional impairment. There was no prominent brain neuronal injury in the 4F groups. Conclusions The present study demonstrated cumulative brain injury from MV-WBV and validated the preventive effects of 4F preconditioning.

Background: Lipomas are common benign tumors. When they develop in proximity to peripheral nerves, they can cause neurologic symptoms secondary to mass effect. Previous reports have shown symptom resolution after removal of lipomas compressing various upper extremity peripheral nerves. However, brachial plexus lipomas are relatively rare. Our multidisciplinary experience with brachial plexus lipoma resection is reviewed in the largest case series to date. Methods: A retrospective chart review of all patients undergoing resection of brachial plexus lipomatous tumors between 2006 and 2016 was performed. Patient demographic data, diagnostic imaging, clinical presentation, operative details, surgical pathology, and clinical outcomes were reviewed. Results: Twelve brachial plexus lipomatous tumors were resected in 11 patients: 10 lipomas, 1 hibernoma, and 1 atypical lipomatous tumor. The most common tumor location was supraclavicular (50%), followed by axillary (42%), and proximal medial arm (8%). The most common brachial plexus segment involved was the upper trunk (50%), followed by posterior cord (25%), lateral pectoral nerve (8%), lower trunk (8%), and proximal median nerve (8%). Most patients presented with an enlarging painless mass (58%). Of the patients who presented with neurologic symptoms, symptoms resolved in the majority (80%). Conclusions: Brachial plexus lipomas are rare causes of compression neuropathy in the upper extremity. Careful resection and knowledge of brachial plexus anatomy, which may be distorted by the tumor, are critical to achieving a successful surgical outcome with predictable symptom resolution. Finally, surveillance magnetic resonance imaging may be warranted for atypical lesions.

Insidious brain microinjury from motor vehicle-induced whole-body vibration (WBV) has not yet been investigated. For a long time we have believed that WBV would cause cumulative brain microinjury and impair cerebral function, which suggests an important risk factor for motor vehicle accidents and secondary cerebral vascular diseases. Fifty-six Sprague-Dawley rats were divided into seven groups (n = 8): 1) 2-week normal control group, 2) 2-week sham control group (restrained in the tube without vibration), 3) 2-week vibration group (exposed to whole-body vibration at 30 Hz and 0.5g acceleration for 4 hr/day, 5 days/week, for 2 weeks), 4) 4-week sham control group, 5) 4-week vibration group, 6) 8-week sham control group, and 7) 8-week vibration group. At the end point, all rats were evaluated in behavior, physiological, and brain histopathological studies. The cerebral injury from WBV is a cumulative process starting with vasospasm squeezing of the endothelial cells, followed by constriction of the cerebral arteries. After the 4-week vibration, brain neuron apoptosis started. After the 8-week vibration, vacuoles increased further in the brain arteries. Brain capillary walls thickened, mean neuron size was obviously reduced, neuron necrosis became prominent, and wide-ranging chronic cerebral edema was seen. These pathological findings are strongly correlated with neural functional impairments. © 2014 Wiley Periodicals, Inc.

A new tool was developed for large volume sampling to facilitate marine microbiology and biogeochemical studies. It was developed for remotely operated vehicle and hydrocast deployments, and allows for rapid collection of multiple sample types from the water column and dynamic, variable environments such as rising hydrothermal plumes. It was used successfully during a cruise to the hydrothermal vent systems of the Mid-Cayman Rise. The Suspended Particulate Rosette V2 large volume multi-sampling system allows for the collection of 14 sample sets per deployment. Each sample set can include filtered material, whole (unfiltered) water, and filtrate. Suspended particulate can be collected on filters up to 142 mm in diameter and pore sizes down to 0.2 μm. Filtration is typically at flowrates of 2 L min−1. For particulate material, filtered volume is constrained only by sampling time and filter capacity, with all sample volumes recorded by digital flowmeter. The suspended particulate filter holders can be filled with preservative and sealed immediately after sample collection. Up to 2 L of whole water, filtrate, or a combination of the two, can be collected as part of each sample set. The system is constructed of plastics with titanium fasteners and nickel alloy spring loaded seals. There are no ferrous alloys in the sampling system. Individual sample lines are prefilled with filtered, deionized water prior to deployment and remain sealed unless a sample is actively being collected. This system is intended to facilitate studies concerning the relationship between marine microbiology and ocean biogeochemistry.

Introduction: After nerve injury, excessive calcium impedes nerve regeneration. We previously showed that calcitonin improved nerve regeneration in crush injury. We aimed to validate the direct effect of calcitonin on transected and repaired nerve. Methods: Two rat groups (n = 8) underwent sciatic nerve transection followed by direct repair. In the calcitonin group, a calcitonin-filled mini-osmotic pump was implanted subcutaneously, with a catheter parallel to the repaired nerve. The control group underwent repair only, without a pump. Evaluation and comparison between the groups included: (1) compound muscle action potential recording of the extensor digitorum longus (EDL) muscle; (2) tetanic muscle force test of EDL; (3) nerve calcium concentration; and (4) nerve fiber count and calcified spot count. Results: The calcitonin pump group showed superior recovery. Conclusions: Calcitonin affects injured and repaired peripheral nerve directly. The calcitonin-filled mini-osmotic pump improved nerve functional recovery by accelerating calcium absorption from the repaired nerve. This finding has potential clinical applications. Muscle Nerve 51: 229–234, 2015

A 20-year-old male was evaluated for winging of the scapula and an enlarging axillary mass of 4 months' duration. Imaging demonstrated a multiloculated cystic lesion that extended into the axilla and superiorly displaced the brachial plexus and axillary vessels surrounding an exostotic mass arising from the scapula. Surgery confirmed the mass to be a benign osteochondroma with a reactive bursa. The long thoracic nerve was intact and the serratus anterior muscle contracted normally with nerve stimulation. The scapular winging resolved completely following resection of the osteochondroma, and shoulder and arm function remained normal. A literature review of causes of pseudo-winging of the scapula was performed. Scapular osteochondroma is a rarely reported cause of scapula winging.

After a nerve injury, calcium concentration in the intra-nerve fiber drastically increases. The purpose of our study was to test an implantable micro-osmotic pump to deliver medications to accelerate calcium absorption, thereby greatly improving nerve regeneration. Twenty-four SD rats were divided into four groups of six each: (1) Sham control: crush injury to sciatic nerve only; (2) Crush injury with a Nifedipine pump; (3) Crush injury with a Calcitonin pump; (4) Crush injury with a Saline pump. Each rat's right sciatic nerve was crushed. The micro-osmotic pump was implanted in the neck, and the dripping tube was routed to the injured nerve. After four weeks of survival time, compound muscle action potential (CMAP), tetanic muscle force (TMF), myelinated nerve fiber area (NFA), nerve calcium concentration (NCC), and calcified spots (CS) were evaluated. The calcium absorption rate (CAR) was also determined. The order from highest to lowest recovery rate was Nifedipine>Calcitonin>Sham control>Saline. Differences among the groups were statistically significant (P

0.4 Sr0.5Ba0.1TiO3 abstract The system LSBT/YSZ (LSBT is La0.4Sr0.5Ba0.1TiO3) is a promising combination as an anode material for full ceramic SOFCs. An anode comprising a porous layer of YSZ impregnated with LSBT shows good performance for conversion of high sulfur content fuels. The microstructures within the composite matrix were determined and correlated with the parameters of the production process. The anodes were characterized electrochemically using impedance spectroscopy (EIS) and potentiodynamic tests per- formed at 850

Our previous studies showed that the functional recovery of an injured nerve correlates with calcium absorption, and that acceleration of this absorption can greatly improve regeneration. In our study, we examined effects of the calcium concentration on cultured Schwann cells obtained from the rat sciatic nerve. Using published methods and simple calculations, we measured the calcium concentration inside normal and injured (crushed) nerve fibers and found that the injured-nerve internal calcium concentration is 16.8 mM, on average. The cells, including Schwann cells, were isolated from an intact sciatic nerve and cultured with various Ca2+ concentrations of calcium-spiked media, from the normal (1.8 mM) to 5.0–16.8 mM. The cells were fixed, blocked, and incubated with Anti-S-100, Goat-Anti-Mouse, and Propidium Iodide. They were viewed under fluorescent conditions to identify the Schwann cells. All the cells in the control dishes were viable, and there were large numbers of Schwann cells present. All the experimental dishes showed the profound concentration-dependent harmful effect of excessive calcium on the number and type of cells present. The high level of calcium corresponding to nerve injury severely affected Schwann and all other cell survival and growth in this cell culture study. Thus, Schwann cell survival and growth are very sensitive to and negatively affected by higher calcium levels than that in the normal media.

Undoped BaTiO 3 perovskite oxide is more effective than SrTiO 3 and La 2 Ti 2 O 7 oxide as anode catalyst in SOFC fueled with H 2 S-containing methane. Electrochemical performance, impedance spectroscopy and other characterizations show that pure BaTiO 3 is a good anode catalyst for conversion of methane in SOFC, especially in H 2 S-containing atmospheres. Compared with SrTiO 3 and La 2 Ti 2 O 7 samples, the BaTiO 3 −based fuel cell has higher resistance to carbon deposition, better electrochemical performance and much higher stability during long term operation. A maximum power density of 135 mW cm −2 was achieved at 900 °C with 0.5% H 2 S–CH 4 in a fuel cell having a 300 μm thick YSZ electrolyte. High catalytic activity for methane conversion, mixed electronic and ionic conductivity, and the surface basicity of BaTiO 3 unexpectedly provides promising performance as anodes in SOFC.

The performance of La0.4Sr0.6TiO3±δ-Y0.2Ce0.8O2−δ (LST-YDC) composite anodes in solid oxide fuel cells significantly improved when 0.5% H2S was present in syngas (40% H2, 60% CO) or hydrogen. However, electrochemical impedance spectroscopy measurements at OCV showed that polarization resistance of the cell increased when the concentration of H2S exceeded 0.5%. Gas chromatographic and mass spectrometric analyses revealed that the rate of electrochemical oxidation of all fuel components improved when H2S was present in the fuel. Electrochemical stability tests performed under potentiostatic conditions showed that there was no power degradation caused by the presence of H2S in different feeds, and that there was power enhancement when 0.5% H2S was present.

A cathode-supported SOFC consisting of LSM (La 0.8 Sr 0.2 MnO 3− δ ) cathode supporter, LSM–Sm 0.2 Ce 0.8 O 2− δ (SDC) cathode functional layer (CFL), yttria stabilized zirconia (YSZ)/SDC bi-layered electrolyte and Ni-YSZ anode layer was fabricated by a slurry spin coating technique. The influence of the porosity in both the CFL and cathode supporter on the electrochemical properties of the cells has been investigated. It was found that properly controlling the porosity in the CFL would improve the performance of the cells using O 2 in the cathode side (O 2 -cells), with a maximum power density (MPD) value achieving as high as 0.58 W cm −2 at 850 °C. However, this improvement is not so evident for the cells using air in the cathode side (air-cells). When increasing the porosity in the cathode-supporter, a significant increase of the power density for the air cells due to the decreasing R conc,c (cathode concentration polarization to the cell resistance) can be ascertained. In terms of our analysis on various electrochemical parameters, the R act (activation polarization to the cell resistance) is assumed to be mainly responsible for the impedance arcs measured under the OCV condition, with a negligible R conc,c value being able to be detected in our impedances. In this case, a significant decreasing size of the impedance arcs due to the increasing porosity in the cathode supporter would correspond to a decrease of the R act values, which was proved to be induced by the decreasing R conc,c .

Electrochemical performance, impedance spectroscopy and carbon tolerance analysis show, for the first time, that molybdenum carbide has great potential for application as anode catalyst in proton-conducting solid oxide fuel cells. Ethylene and stable power density are coproduced from ethane in proton-conducting SOFC with molybdenum carbide as anode catalyst and BCZY as electrolyte. Keywords: Molybdenum carbide, Proton-conducting electrolyte, Solid oxide fuel cell, Ethane dehydrogenation to ethylene

Ni–P amorphous alloy coatings with different P content are coated onto porous Ni foam by means of electroless plating. The plated Ni foams exhibit excellent carbon deposition resistance and structure stability in syngas at elevated temperature when P content is higher than 6.5 wt% in the coating. Anode supported solid oxide fuel cells fabricated using a spin coating process have a maximum power density of ∼1.3 W cm −2 in H 2 at 850 °C and ∼0.8 W cm −2 in syngas at 800 °C. The H 2 -fueled cells with naked and plated Ni foam current collector have very similar internal ohmic resistance and power density, which confirm the good electronic conductivity of the coatings. The syngas-fueled cells with Au mesh and plated Ni foam current collector reach almost identical power density and internal resistance, and the latter has no apparent degradation of power output during extended fuel cell stability testing. Thus Ni–P is a promising carbon deposition resistant coating of current collector for syngas-fueled solid oxide fuel cells.

Copper coated nickel foam with Cu/Ni ratio of 2.5 was fabricated using electrochemical plating and characterized using XRD, SEM, EDS and Van der Pauw four point conductivity measurements. Copper coated nickel foam exhibited good stability of electronic conductivity and mechanical strength during more than 150 h exposure to 500 ppm H 2 S-containing syngas at 750 °C. In contrast, uncoated nickel foam readily underwent severe carbon deposition and brittle fracture resulting in dramatic increase of electronic resistance under the same testing conditions. Copper coated nickel foam is a promising current collector for H 2 S-containing syngas solid oxide fuel cells (SOFCs).

Addition of 0.5% hydrogen sulfide into syngas improved the performance of a oxygen conducting solid oxide fuel cell by enhancing the electrochemical oxidation of carbon monoxide. However, there was no consumption of hydrogen sulfide, as determined by mass spectrometric and gas chromatographic analyzes of the effluent gases during potentioidynamic and potentiostatic runs. The anode was a composite of lanthanum strontium titanate and yttrium cerium oxide. The electrochemical performance of the fuel cell fuelled with syngas containing 0.5% hydrogen sulfide was stable during 30 h galvanostatic tests.

Background Since the 1980s, the C7 nerve root has gained clinical relevance as a donor nerve in severe brachial plexus root avulsion injuries. Despite success with the cross-chest C7 nerve transfer, inducing injury on an otherwise normal side hinders global acceptance. By sacrificing the C7 nerve root, a predictable pattern of transient sequelae is seen, including extensor weakness and index and middle finger anesthesia. The purpose of this study is to observe cortical activity during direct stimulation of the C7 nerve root using blood oxygen level dependent functional magnetic resonance imaging (fMRI) in a rat model. Methods A total of 12 male Sprague-Dawley rats, weighing 200–250 g, were used in this study. Following an acclimation period of 1 week, 12 rats underwent exposure and dissection of the brachial plexus. Seven rats underwent placement of an implantable electrode (AISI 304, Plastics1, Roanoke, VA, USA) on the C7 nerve root, while five rats underwent electrode placement on the radial nerve. All animals then underwent fMRI during direct nerve stimulation. Ten consecutive coronal images were obtained during nerve stimulation, using a 9.4-T small-animal MRI scanner. Results Cortical activation is seen within a very specific area of the primary sensory region of the forelimb during C7 nerve root stimulation. The cortical activation seen during radial nerve stimulation includes that seen during C7 stimulation but extends several slices caudally. Conclusions The sensory representation of the C7 nerve root is seen in only a small area in the S1FL region compared to that seen in the terminal branches of the brachial plexus. However, this area shows a significant overlap with the S1FL area of activation seen during radial nerve stimulation. This makes sense as the C7 nerve root contributes some, but not all, sensory axons to the radial nerve. Mapping of the C7 cortical representation in the rat brain not only adds to the ongoing development of the motor and sensory ratunculus but also provides an important foundation to study subsequent C7 donor nerve models.

Ethane and electrical power are co-generated in proton ceramic fuel cell reactors having Cr 2 O 3 nanoparticles as anode catalyst, BaCe 0.8 Y 0.15 Nd 0.05 O 3− δ (BCYN) perovskite oxide as proton conducting ceramic electrolyte, and Pt as cathode catalyst. Cr 2 O 3 nanoparticles are synthesized by a combustion method. BaCe 0.8 Y 0.15 Nd 0.05 O 3− δ (BCYN) perovskite oxides are obtained using a solid state reaction. The power density increases from 51 mW cm −2 to 118 mW cm −2 and the ethylene yield increases from about 8% to 31% when the operating temperature of the solid oxide fuel cell reactor increases from 650 °C to 750 °C. The fuel cell reactor and process are stable at 700 °C for at least 48 h. Cr 2 O 3 anode catalyst exhibits much better coke resistance than Pt and Ni catalysts in ethane fuel atmosphere at 700 °C.

Cu surface modified nickel foam is obtained by heating copper coated nickel foam in a reducing atmosphere. La0.75Sr0.25Cr0.5Mn0.5O3−δ (LSCM) perovskite oxide is prepared using a sol–gel combustion method. The modified foams and LSCM powders exhibit excellent resistance to carbon deposition in syngas at high temperatures. Furthermore, Cu modified foams show better mechanical strength compared to bare Ni foam, which readily cracks after exposure to syngas at high temperature. LSCM retains its perovskite structure during exposure to syngas or carbon monoxide at 900 °C for 10 h. Cu surface modified Ni foam current collector demonstrates good chemical compatibility with LSCM in syngas atmosphere at high temperature. Syngas solid oxide fuel cells (SOFCs) are assembled using Cu modified Ni foam anode current collector, LSCM anode catalyst, YSZ electrolyte, and porous Pt cathode. The present fuel cell provides similar power density to one with gold anode current collector and has excellent stability during operation at 900 °C.

The structure, morphology and electrical conductivity for BaZr0.8Y0.2O3 − δ (BZY20) and BZY20 with ZnO sintering aid are compared. Both materials have a very dense structure. The bulk and total conductivities for BZY20 with ZnO sintering aid are lower than those of BZY20 in the range 400 to 650 °C. Both materials are stable up to 650 °C in hydrogen containing 5000 ppm H2S. Dense anode-supported electrolyte thin films are prepared using spin coating.

A new oxide-salt composite electrolyte, YSZ–K3PO4–Ca3(PO4)2, shows proton conductivity in the order of 10−2 S/cm at 700 °C. The proton transport number, determined using a hydrogen concentration cell, rises from more than 93% at 550 °C to 99% at 700 °C. The composite electrolyte is chemically stable in H2S containing atmosphere, and so is a good candidate electrolyte material for H2S solid oxide fuel cells applications.

The level of barium doping in lanthanum strontium titanate (La0.4Sr0.6−xBaxTiO3, 0 ≤ x ≤ 0.2; LST, x = 0; LSBT, x > 0), prepared by solid state synthesis, affects its performance as anode in solid oxide fuel cells (SOFCs). Cell structures of LST and all LSBT were similar. The oxidation state of Ti in all compounds was reduced by a comparable amount when LST or LSBT was heated under reducing conditions to form La0.4Sr0.6−xBaxTi0.594+Ti0.413+O2.97. All fuel cells using LST or LSBT had high activity for conversion of hydrogen or methane, and the activity increased with the level of substitution by Ba. In addition, performance was enhanced when H2S was present in either CH4 or H2 fuel. There was good contact between YSZ electrolyte and each LSBT or LSB anode.

About 20 nm precursor powders for BaCe0.85Y0.15O3−δ (BCY) were synthesized by combustion method. The nanopowder had about 100 times larger specific volume than sintered BCY. A bi-layered proton conducting membrane having a thick porous BCY substrate and an integrally supported dense BCY thin film were co-fabricated facilely by pressing two layers comprising the precursor powder and its mixture with starch, followed by co-sintering at high temperature. Pt was impregnated into the porous BCY layer matrix as anode catalyst for dehydrogenation of ethane to ethylene. A hydrocarbon solid oxide fuel cell with the BCY thin film electrolyte and Pt electrodes demonstrated high selectivity (90.5%) to ethylene at 36.7% ethane conversion with co-generation of 216 mW cm−2 electrical energy output at 700 °C. The ethane conversion and ethylene selectivity increased with current density.

Strontium-doped lanthanum vanadate, La0.7Sr0.3VO4, LSV, was prepared via a nitrate-citrate combustion method. The phase formation process of LSV was studied using thermogravimetric analysis and X-ray diffraction (XRD). A pure phase of LSV was formed during baking at 900 °C for 7 h in 10% H2−Ar. LSV is chemically and electrochemically stable in H2S-containing syngas (40% H2, 60% CO, and 5000 ppm H2S). LSV is an active anode catalyst for use in solid oxide fuel cells (SOFCs), and a H2-air fuel cell with configuration LSV/YSZ/Pt provided maximum power density of 210 mW cm−2 at 900 °C and a current density close to 400 mA cm−2. Impedance measurements showed that the anodic polarization resistance depended on the fuel gas, and was highest for CO and lowest for H2. The ohmic and polarization resistance of the cell decreased with increase in temperature.

The performance of a series of perovskite oxides having the mutual chemical formula and structure La0.75Sr0.25Cr0.5X0.5O3−δ (X = Co, Fe, Ti, Mn) as solid oxide fuel cell anode electrocatalysts depends on the nature of the substituent element X. The electrocatalytic activity for methane oxidation in a fuel cell correlates well with ex-situ temperature programmed catalytic conversion of CH4, X = Co > Mn ∼ Fe > Ti, under temperature programmed reaction conditions in 5% CH4/He. The total conductivity of the materials in air decreases X = Co > Fe > Mn > Ti. Within the series of catalysts, the order of maximum fuel cell power density depended on feed: CH4, X = Fe > Mn > Ti; H2, X = Fe > Mn > Ti; and 0.5% H2S/CH4, X = Ti > Fe > Mn. The Co-containing catalyst was unstable under reducing conditions. A process is proposed to explain the difference in catalyst order and enhanced activities in H2S/CH4 as fuel compared to CH4 alone.

Whereas Ce0.9Sr0.1Cr0.5V0.5O3 is an active fuel cell anode catalyst for conversion of only the H2S content of 0.5% H2S–CH4 at 850 °C, inclusion of 5 wt% NiO to form a composite catalyst enabled concurrent electrochemical conversion of CH4. A fuel cell with a 0.3 mm thick YSZ membrane and Ce0.9Sr0.1Cr0.5V0.5O3 as anode catalyst had a maximum power density of 85 mW cm−2 in 0.5% H2S–CH4 at 850 °C, arising only from the electro-oxidation of H2S. Using a same thick membrane, promotion of the anode with 5 wt% NiO increased the total anode electro-oxidation activity to afford maximum power density of 100 mW cm−2 in 0.5% H2S–CH4. The same membrane provided 30 mW cm−2 in pure CH4, showing that the incremental improvement arose substantially from CH4 conversion. Performance of each anode was stable for over 12 h at maximum power output. XPS and XRD analyses showed that an increase in conductivity of Ce0.9Sr0.1Cr0.5V0.5O3 in H2S-containing environments resulted from a change in composition and structure from the tetragonal oxide to monoclinic Ce0.9Sr0.1Cr0.5V0.5(O,S)3.

The stability and activity in 0.5% H 2 S–CH 4 of Ce 0.9 Sr 0.1 VO 3 and Ce 0.9 Sr 0.1 VO 4 anode materials for H 2 S-containing CH 4 fueled SOFCs have been determined. XRD showed that Ce 0.9 Sr 0.1 VO 4 was reduced when the fuel gas was 0.5% H 2 S–CH 4 , while Ce 0.9 Sr 0.1 VO 3 remained stable over 24 h at 950 °C. Electrochemical tests in 0.5% H 2 S–CH 4 showed stable performance at 950 and 800 °C for cells comprising Ce 0.9 Sr 0.1 VO 3 |YSZ|Pt. Comparison of fuel cell performances using 0.5% H 2 S–CH 4 , 0.5% H 2 S–N 2 and 5% H 2 S–N 2 as feeds showed that Ce 0.9 Sr 0.1 VO 3 was not active for oxidation of methane, but highly active for conversion of H 2 S. Electrochemical impedance results were consistent with the finding that the anode was activated only in an environment that contained H 2 S. Conductivity measurements showed there was an increase in conductivity in H 2 S-containing environments, and that this increase resulted from a change in composition and structure from the oxide to monoclinic Ce 0.9 Sr 0.1 V(O,S) 3 , as evidenced by XPS and XRD analyses.

ZnO-doped BaZr0.85Y0.15O3−δ perovskite oxide sintered at 1500 °C has bulk conductivity of the order of 10−2 S cm−1 above 650 °C, which makes it an attractive proton-conducting electrolyte for intermediate-temperature solid oxide fuel cells. The structure, morphology and electrical conductivity of the electrolyte vary with sintering temperature. Optimal electrochemical performance is achieved when the sintering temperature is about 1500 °C. Cathode-supported electrolyte assemblies were prepared using spin coating technique. Thin film electrolytes were shown to be dense using SEM and EDX analyses.

Co-doping of yttrium doped mixed barium cerate/zirconate perovskite (BCZY) with small amounts of Pr (BCZYP) substantially increases electrical conductivity while retaining structural and chemical stability. BCZYP is pre- dominantly a proton conductor at temperatures up to 600-650˚C, whereas it is a mixed proton/oxide ion/electron conduc- tor at higher temperatures. The co-doped BCZYP perovskite can be useful for applications requiring proton conduction at intermediate temperatures.

The kinetics of liquid catalytic dehydration of methanol over an ion exchange resin (Amberlyst 35) has been determined for the temperature range 343 to 403 K using a batch reactor. The experimental data are described well by an Eley-Rideal type kinetic expression, for which the surface reaction is the rate-determining step. A catalytic distillation process for methanol dehydration to dimethyl ether (DME) has been modeled using the experimentally determined kinetic data. The results were incorporated into the rate-controlled reaction mode for RadFrac, a part of the commercial simulation program Aspen Plus. It was shown that synthesis of high purity DME can be achieved using a single catalytic distillation column. Thus there is significant potential for reduction of overall capital cost for a plant for methanol dehydration to DME when compared to conventional production facilities that involve separate reaction and distillation processes.

Yttrium-doped barium zirconate (BZY) perovskite structured materials are the first protonic electrolytes proven to be stable for use at intermediate temperatures (450–700 °C) in hydrogen containing 5000 ppm H 2 S. Structures of materials were characterized and stability was confirmed using XRD, SEM and EDX methods. While BZY powders and membranes are stable proton conductors in H 2 S-containing atmosphere, in contrast Y-doped barium cerate has poor chemical stability. The resistance of BZY, measured by impedance spectroscopy, is strongly dependent on temperature and atmosphere. Total conductivity of BZY increased with temperature in both hydrogen and dilute H 2 S atmospheres.

Yttrium-doped barium cerate, BaCe0.85Y0.15O3−α (BCY15), membranes are proton-conducting electrolytes for intermediate-temperature protonic ceramic fuel cells (IT-PCFC), useful for, among other processes, co-production of power and ethylene by dehydrogenation of ethane. BCY15 membranes showed good conductivity at intermediate temperatures, 15 and 20 mS cm−1 at 700 and 750 °C, respectively. Maximum power density was 174 mW cm−2 at 700 °C, with a corresponding current density of 320 mA cm−2, using a C2H6,Pt/BCY15/Pt,O2 fuel cell, with a ca. 0.5 mm thick membrane, producing 34% ethane conversion with 96% ethylene selectivity Comparison of performances using vertical and horizontal set-ups showed that horizontal set-ups are subject to torsional strain, causing reduced cell performance resulting from even minor leakage at the glass seal.

A new, highly active and stable anode catalyst material LaCrO3−VOx−YSZ has been developed for solid oxide fuel cell systems fueled with impure hydrogen. The presence of CO in the anode feed enhanced initial fuel cell performance when compared to the use of CO-free H2 containing 5000 ppmv H2S. Impedance spectra showed that the anode polarization resistance decreased in the presence of CO. Current density of 450 mA/cm2 at 0.6 V and maximum power density of 260 mW/cm2 (at 450 mA/cm2) were obtained at 900 °C. XRD (X-ray diffraction) and XPS (X-ray photoelectron spectroscopy) analyses showed that the new catalyst was chemically stable in H2S-rich syngas or hydrogen. However, when syngas was used, slow carbon deposition compromised the fuel cell performance during long tests at high temperatures.