bluuebunny/crossref_metadata_2025_split huggingface dataset:
Robot-assisted pancreatoduodenectomy with preservation of the vascular supply for autologous islet cell isolation and transplantation: a case report
Authors: Giulianotti Piero , Gorodner Veronica , Kinzer Katie , Benedetti Enrico , Oberholzer Jose 
Published: March 2012

Abstract

Introduction
For patients with chronic pancreatitis presenting with medically intractable abdominal pain, surgical intervention may be the only treatment option. However, extensive pancreatic resections are typically performed open and are associated with a substantial amount of postoperative pain, wound complications and long recovery time. Minimally invasive surgery offers an avenue to improve results; however, current limitations of laparoscopic surgery render its application in the setting of chronic pancreatitis technically demanding. Additionally, pancreatic resections are associated with a high incidence of diabetes. Transplantation of islets isolated from the resected pancreas portion offers a way to prevent post-surgical diabetes; however, preservation of the vascular supply during pancreatic resection, which determines islet cell viability, is technically difficult using current laparoscopic approaches. With recent advances in the surgical field, robotic surgery now provides a means to overcome these obstacles to achieve the end goals of pain relief and preserved endocrine function. We present the first report of a novel, minimally invasive robotic approach for resection of the pancreatic head that preserves vascular supply and enables the isolation of a high yield of viable islets for transplantation.

Case presentation
A 35-year old Caucasian woman presented with intractable chronic abdominal pain secondary to chronic pancreatitis, with a stricture of her main pancreatic duct at the level of the ampulla of Vater and distal dilatation. She was offered a robotic-assisted pylorus-preserving pancreatoduodenectomy and subsequent islet transplantation, to both provide pain relief and preserve insulin-secretory reserves.

Conclusion
We present a novel, minimally invasive robotic approach for resection of the pancreatic head with complete preservation of the vascular supply, minimal warm ischemia time (less than three minutes) and excellent islet recovery (134,727 islet equivalent). Our patient is currently pain-free with normal glycemic control. Robot-assisted pylorus-preserving pancreatoduodenectomy and autologous islet transplantation can be safely performed and has the potential to minimize operative traumas as well as to partially preserve endocrine function. Results from this case report suggest that this dual procedure should be considered as a treatment option for patients with chronic pancreatitis at earlier stages of the disease, before irreversible islet loss occurs.
Hypoxia mediated isolation and expansion enhances the chondrogenic capacity of bone marrow mesenchymal stromal cells
Authors: Adesida Adetola B , Mulet-Sierra Aillette , Jomha Nadr M 
Published: March 2012

Abstract
Introduction
The capacity of bone marrow mesenchymal stromal cells (BMSCs) to be induced into chondrocytes has drawn much attention for cell-based cartilage repair. BMSCs represent a small proportion of cells of the bone marrow stromal compartment and, thus, culture expansion is a necessity for therapeutic use. However, there is no consensus on how BMSCs should be isolated nor expanded to maximize their chondrogenic potential. During embryonic development pluripotent stem cells differentiate into chondrocytes and form cartilage in a hypoxic microenvironment.

Methods
Freshly harvested human BMSCs were isolated and expanded from the aspirates of six donors, under either hypoxic conditions (3% O2) or normoxic conditions (21% O2). A colony-forming unit fibroblastic (Cfu-f) assay was used to determine the number of cell colonies developed from each donor. BMSCs at passage 2 (P2) were characterized by flow cytometry for the phenotypic expression of cell surface markers on mesenchymal stem cells. BMSCs at P2 were subsequently cultured in vitro as three-dimensional cell pellets in a defined serum-free chondrogenic medium under normoxic and hypoxic conditions. Chondrogenic differentiation of the BMSCs was characterized by biochemical and histological methods and by quantitative gene-expression analysis.

Results
After 14 days of culture, the number of BMSC colonies developed under hypoxia was generally higher (8% to 38% depending on donor) than under normoxia. BMSCs were positive for the cell surface markers CD13, CD29, CD44, CD73, CD90, CD105 and CD151, and negative for CD34. Regardless of the oxygen tension during pellet culture, hypoxia-expanded BMSC pellets underwent a more robust chondrogenesis than normoxia-expanded BMSC pellets after three weeks of culture, as judged by increased glycosaminoglycan synthesis and Safranin O staining, along with increased mRNA expression of aggrecan, collagen II and Sox9. Hypoxic conditions enhanced the mRNA expression of hypoxia inducible factor-2 alpha (HIF-2α) but suppressed the mRNA expression of collagen X in BMSC pellet cultures regardless of the oxygen tension during BMSC isolation and propagation.

Conclusions
Taken together, our data demonstrate that isolation and expansion of BMSCs under hypoxic conditions augments the chondrogenic potential of BMSCs. This suggests that hypoxia-mediated isolation and expansion of BMSCs may improve clinical applications of BMSCs for cartilage repair.
Survival of Older Patients With Cancer in the Veterans Health Administration Versus Fee-for-Service Medicare
Authors: Landrum Mary Beth , Keating Nancy L. , Lamont Elizabeth B. , Bozeman Samuel R. , Krasnow Steven H. , Shulman Lawrence , Brown Jennifer R. , Earle Craig C. , Rabin Michael , McNeil Barbara J. 
Published: March 2012

Purpose The Veterans Health Administration (VHA) provides high-quality preventive chronic care and cancer care, but few studies have documented improved patient outcomes that result from this high-quality care. We compared the survival rates of older patients with cancer in the VHA and fee-for-service (FFS) Medicare and examined whether differences in the stage at diagnosis, receipt of guideline-recommended therapies, and unmeasured characteristics explain survival differences. Patients and Methods We used propensity-score methods to compare all-cause and cancer-specific survival rates for men older than age 65 years who were diagnosed or received their first course of treatment for colorectal, lung, lymphoma, or multiple myeloma in VHA hospitals from 2001 to 2004 to similar FFS-Medicare enrollees diagnosed in Surveillance, Epidemiology, and End Results (SEER) areas in the same time frame. We examined the role of unmeasured factors by using sensitivity analyses. Results VHA patients versus similar FFS SEER-Medicare patients had higher survival rates of colon cancer (adjusted hazard ratio [HR], 0.87; 95% CI, 0.82 to 0.93) and non–small-cell lung cancer (NSCLC; HR, 0.91; 95% CI, 0.88 to 0.95) and similar survival rates of rectal cancer (HR, 1.05; 95% CI, 0.95 to 1.16), small-cell lung cancer (HR, 0.99; 95% CI, 0.93 to 1.05), diffuse large–B-cell lymphoma (HR, 1.02; 95% CI, 0.89 to 1.18), and multiple myeloma (HR, 0.92; 95% CI, 0.83 to 1.03). The diagnosis of VHA patients at earlier stages explained much of the survival advantages for colon cancer and NSCLC. Sensitivity analyses suggested that additional adjustment for the severity of comorbid disease or performance status could have substantial effects on estimated differences. Conclusion The survival rate for older men with cancer in the VHA was better than or equivalent to the survival rate for similar FFS-Medicare beneficiaries. The VHA provision of high-quality care, particularly preventive care, can result in improved patient outcomes.
Faecaloma in ano
Authors: Jalil O , Jones H , Stephenson BM , Williams GL 
Published: March 2012

Introduction Faecal concretions or faecalomas (’stone of faeces’) are symptomatic of many well-recognised colorectal conditions. Faecalomas are usually located in the colon or rectum and associated with disorders of colorectal transit. We describe an unusual case of ’faecaloma in ano’ secondary to a chronic fissure in ano. A 67-year-old woman with a 10-year history of chronic constipation and intermittent anal discomfort presented with a painless perianal lump of similar duration. Methods The patient’s case notes were reviewed and a literature search was carried out. Results Examination under anaesthesia, sigmoidoscopy and anoscopy did not reveal any mucosal abnormality or an internal opening or any connection with the perianal lump. The mass was enucleated after incising the skin, leaving behind a cavity completely separate from the anal canal and sphincters. Histology revealed inspissated faecal material with evidence of calcification. Conclusions Chronic fissures may be complicated by sepsis and, rarely, a ’fissure fistula’ may develop. We suspect that this was the underlying pathogenesis of this ’faecaloma in ano’. The term faecaloma in ano befits the clinical picture.
EXHIBITION REVIEWS
Authors: Damgaard Kristoffer , Sakr Yasir 
Published: March 2012

'BAYT AL-AQQAD - A HOUSE IN DAMASCUS', THE DAVID COLLECTION, COPENHAGEN, UNTIL AUGUST 7, 2011
'OUT OF PLACE', DARAT AL-FUNUN – THE KHALID SHOMAN FOUNDATION, AMMAN, JUNE 7–SEPTEMBER 29, 2011
Towards systematics of calcite biocrystals: insight from the inside
Authors: Schmahl Wolfgang W. , Griesshaber Erika , Kelm Klemens , Ball Alexander , Goetz Andreas , Xu Dayin , Kreitmeier Lisa , Jordan Guntram 
Published: March 2012

Abstract
Biocrystals of calcite are frequent as they are employed by many phylae of organisms in shells, eggshells, teeth, spines or sensoric apparatus. The calcite phase in these materials occurs in a range of constitutions, from polycrystalline fabrics to “single-crystals”. We demonstrate systematics of calcite biocrystal architectures, from the hybrid composite mesocrystal fibres of brachiopod and mollusc shells, via the submillimeter-sized hybrid composite crystal aggregates formed by mesocrystal fibres with both morphological co-orientation and lattice co-oriäentation, to more complex purpose-oriented multiplex äcomposite crystals of echinoderm teeth, which feature a high degree of single-crystal-like 3D orientational correlation of microstructural elements of different morphology and composition. These systematics rely on observations by electron backscatter diffraction (EBSD) and TEM.
Atom-Probe Tomographic Studies of Thin Films and Multilayers
Authors: Larson David J. , Cerezo Alfred , Juraszek Jean , Hono Kazuhiro , Schmitz Guido 
Published: March 2012

AbstractThis article reviews investigations of the growth and reactions within thin metal and oxide films using atom-probe tomography. Included in this review are (1) studies of interfacial and growth reactions in magnetoresistive metallic, metal/oxide, and magnetic magnetostrictive multilayers; (2) comparison of selected portions of these results to simulated film growth using molecular dynamics; and (3) study of the origin of room-temperature ferromagnetism in dilute magnetic semiconductors. Information of this type is useful in order to understand the formation and thermal evolution of thin films (and to compare to theory and modeling) and, ultimately, to permit further optimization of devices based on thin films.
First-principles transition state study of oxygen reduction reaction on Pt (111) surface modified by subsurface transition metals
Authors: Duan Zhiyao , Datta Aditi , Wang Guofeng 
Published: March 2012

ABSTRACTWe have performed first-principles density functional theory calculations to investigate how subsurface 3d transition metals M (M = Ni, Co, Fe, Ti, or V) affect the energetics and mechanisms of oxygen reduction reaction (ORR) on the outermost Pt mono-surface layer of Pt/M (111) surfaces. We found that the alteration of the ORR mechanism pathway can explain the activity enhancement for ORR on the Pt/M (111) surfaces.
Graphene Composite Materials for Supercapacitor Electrodes
Authors: Lake John , Tanaka Zuki , Chen Bin 
Published: March 2012

ABSTRACTThis study presents a materials development of composite electrode materials of graphene oxide (GO) and transition metal oxide nanostructures. Reduced graphene oxide (rGO) films were obtained by electrophoretic deposition (EPD) onto a conductive substrate. Co3O4 and MnO2 nanostructures were synthesized to form composites with rGO. Graphene materials, with high electrical conductivity, high specific surface area and excellent mechanical properties are ideal for a host of electrical applications. The properties of metal oxides like Co3O4 and MnO2 has allowed for increased energy density, while rGO increases charge storage and transport in the electrical double layer at the electrode/electrolyte interface. Graphene and metal oxide composites offer increased energy density and capacitance compared with traditional double layer supercapacitors.
Gasochromic and electrical properties of Pt-nanoparticle-dispersed tungsten oxide thin films prepared by a sol-gel process
Authors: Yamaguchi Yuki , Nishio Keishi , Kineri Tohru 
Published: March 2012

ABSTRACTIt is well known that tungsten tri-oxide (WO3) exhibits electrochromic and gasochromic properties. When Pt-nanoparticle-dispersed tungsten oxide (Pt-WO3) is exposed to hydrogen gas, the optical and electrical properties of the Pt-WO3 change drastically. Consequently, it is expected that thin films of WO3 can be applied as hydrogen gas leakage sensors. In this study, thin films of Pt-WO3 were prepared on glass substrates using a sol-gel process. The optical and electrical properties of the films were evaluated. Amorphous and crystalline WO3 were easily obtained by changing the heat-treatment temperature. The ion diffusion coefficient of the film depended on the WO3 structure (i.e., whether it was amorphous or crystalline) because the density of amorphous WO3 is lower than that of crystalline WO3. Films with low crystallinity were found to have superior chromic properties to both those with high crystallinity and amorphous films. Thin films of Pt-WO3 prepared at 673K showed the largest change in optical transmittance and electrical conductivity when exposed to H2 gas compared with thin films prepared at other temperatures. When this film was exposed to 100% H2 gas, the normalized transmittance decreased rapidly (in less than 0.2 sec) from 100% to almost 50%. The optical absorbance of the film was dependent on the H2 gas concentration (mixed with N2 gas) in the range from 0.1 to 5% and the relationship between them was linear. The relationship between the electrical conductivity and hydrogen gas concentration (mixed with N2 gas) in the range from 100 to 10000ppm was also linear.
Can You Protect Your Motor Without Sacrificing Performance?
Authors: Guidroz Blair , Barton Steven 
Published: March 2012

Abstract
Achieving balance between performance and longevity of drilling motors is a constant struggle. Operating above recommended parameters delivers higher Rates of Penetration (ROP) but can be too aggressive, causing accelerated component wear and potentially, premature failure. Conservative operation decreases the component wear but can be detrimental to drilling performance. A novel approach to controlling motor performance allows operators to operate at specified limits while preventing load spikes that damage motors.
Stalling is a problem that affects bearing loading, occasionally leading to driveshaft torsional failure, but more commonly causing power section damage in the stator, reported as chunking. Chunking occurs when the elastomer in the stator has reached the fatigue limit and small pieces break free of the profile. The output performance of the power section decreases as the effective area of power section is reduced and it becomes less efficient. Reduction in output performance decreases ROP and operators will typically push motors harder to maintain ROP, further accelerating the time to failure.
An innovative internal device prevents premature failure by limiting the amount of differential pressure applied across the motor. Excess pressure is relieved by porting fluid through the center of the rotor, bypassing the power section inlet. Rotational speed decreases as flow into the power section is decreased. The pre-determined relief point is adjustable to optimize motor performance for specific applications. Preventing motor damage delivers longer drilling hours with reduced unplanned trips.
Field testing of the device has resulted in a significant reduction in motor component damage. ROP improved and was consistent through the drilling program with the controlled and steady operation of the device. Cost per foot decreased as longer intervals were drilled per motor. This device gives operators a new tool to optimize motor performance.
Exploration to Production in 2 Years: A Contracting Strategy Case Study
Authors: Passos Vinicius , McCallum George , Dubey Sharad , Lindsay Gordon 
Published: March 2012

Abstract
The IEA tells us that hydrocarbon fuels will continue to dominate the global energy mix with coal, oil and natural gas supplying almost 80% of primary energy needs. The consequent higher costs of new supply and the challenges of matching supply and demand are not likely to decrease.
Brazil is one of emerging areas offering a cushion to this demand-supply gap. Typically the offshore exploration efforts in Brazil were led by NOC and IOCs. This changed in July 2007 with the creation of a new Independent Brazilian O&G Company. The company acquired 21 exploration blocks in November 2007 and increased its portfolio to 29 blocks by March 2009. The challenge of exploiting the blocks was achieved by setting ambitious, time bound, exploration and production goals and delivering against those goals.
A conventional contracting strategy would have required a large in house team, with relevant technical expertise and multiple service contracts. It would have led the company to recruit heavily and to develop multiple internal processes and procedures prior to being able to start operations. However, the time frame set by the company to deliver the goals required a different approach. The company clearly needed to multiply its talents through rapid access to resources, people and technology in a technology intensive industry.
The company chose an outsourcing strategy pillared on project management, and worked wherever practicable and appropriate to minimize the number of contractors. The majority of the exploration work was contracted to two major contractors, one integrated oilfield service provider and one drilling contractor. This gave the company access a large pool of petro-technical experts, mature processes and a wide portfolio of technologies in a short period of time.
This paper looks at how this strategy allowed the company to successfully achieve its goals and increase value to its stakeholders. It also looks at the issues encountered and how they were productively turned around.
Innovative Well Completions Meet the Challenges of Producing High Wax Crude in a Giant Onshore Field in India
Authors: Kumar Vipin , McKenzie Tim , Singh Ratan , Wenk Andrew , Chandra Santosh 
Published: March 2012

Abstract
The Mangala field located in the sparsely populated, remote, undeveloped Thar Desert of NW India, is the country’s largest onshore producing oilfield. The field development includes 100 production (11 horizontal) and 50 plus water-injection wells, all directionally drilled from wellpads. The oil is waxy, low GOR crude, with a pour point above 40 Deg C. Wells are producing up to 12,000 bopd.
Completion design challenges included; high CO2 content, high wax appearance temperature, high pour point, high viscosities, possible emulsions, sand production and the need for artificial lift. Hot water was selected as the field wide medium for maintaining flow assurance. A completion design was developed, which allows hot water circulation inside the production annulus with a coiled tubing string run with the production tubing to maintain temperatures above pour point. The hot water supply is also used to provide power fluid to the annulus for jet pumping. Some wells have ESPs installed.
Specialized rig setup and well head systems were designed to allow simultaneous deployment of production tubing, heater string, chemical and instrument lines, and ESP cables. The wellhead design ensures that barrier policies are maintained throughout the well construction. Simultaneous running of all completion components warranted a specially designed tubing running system and CT deployment system built into the completion rig. Jet pump power fluid exposes the completion to high loads which also made the completion design quite challenging.
This paper describes the successful design and deployment of these innovative completions and wellhead systems. To date more than 100 completions have been deployed successfully and are delivering ~125,000 bopd. All this has been achieved with excellent HSE performance (~970 days of LTI free operation) on the completion rig.
Performance Drilling- Innovative Concepts Improve Benchmarking and Optimization Processes
Authors: Mensa-Wilmot Graham , Yimpoonsap Pakarang 
Published: March 2012

Abstract
Performance drilling1, 2(PD), acknowledged as an enabler to performance improvement and drilling cost reduction, needs to be executed with specific inputs and guidelines. Benchmarking plays a critical role in the PD process. For PD to be effective, benchmarking must ensure that data evaluations and comparisons are conducted under similar conditions.
To achieve this goal, three innovative performance drilling concepts – formation drillability3 (FI), drilling index4 (DI) and performance drilling evaluation (PDE), have been developed to improve the benchmarking process. In comparison to the industry’s current methods, the new concepts look at data analysis and interpretation differently. These new concepts establish a "total" benchmarking process. Rock mechanics data, as well as drilling data, are analyzed through a normalization process based on pre–determined project objectives. The objectives are identified, ranked, and given weighting constants, based on their contributions to project success and cost reductions.
FI normalizes and compares rock mechanics effects for all wells being analyzed, through calculation of dimensionless parameters. DI assigns weighted factors to project objectives, normalizes drilling parameters, compares drilling efficiency levels for all bits, and calculates dimensionless evaluaton parameters. PDE, a final dimensionless parameter, captures the effects of FI and DI on the benchmarking process. As a result, and through use of these concepts, benchmarking processes are executed under similar conditions.
Consequently benchmarking, acknowledged as a critical part of the PD process, assumes its rightful dominance in the decision making process. This paper will discuss the process as well as results from projects that have been executed with these principles. A software package, developed to speed up the evaluation and decision making processes, will also be presented. The contributions of these concepts on the PD process will be clearly established.