bluuebunny/crossref_metadata_2025_split huggingface dataset:
Safety Performance: An Operations Approach to Management
Authors: Lane Ian , Watkiss Richard 
Published: June 2009

Abstract
This paper presents a case history of a turnaround in safety performance coincident with the introduction of the Step Change Initiative in the North Sea, from an operations rather than a safety specialist's approach. The safety record on 5 platform drilling facilities in the North Sea during 1996 was exemplary, but deteriorated markedly during 1997. Possible factors including management focus, industry activity levels and the impact of workscope are all discussed, concluding that whilst all may have had an impact none could confidently be targeted as the primary cause.
In an effort to reverse the trend, input was sought from the workforce with the aim of building on existing (and previously effective) safety tools rather than introducing a raft of new initiatives. Shortfalls in the identification of hazard and the management of risk were identified. Improvements in this area including focused crew involvement (via Tool Box Talks, Theoretical Maximum Performance Techniques, and other means), rig equipment upgrading and formal procedures were made. Other key changes included higher visibility of leadership from both KCA and the Client, Shell, and the contentious issue of incentivisation. In all, a 24 point action plan was devised and implemented whilst it was being developed, under the main headers of leadership, risk management and workforce involvement. Early results show an extremely positive trend, not only on the 5 "worst" afflicted installations but across the whole of KCA (LTIF/NLTIF per 200,000 man hours) — (SeeFig. 1). Fig 1KCA Drilling LTIF / NLTIF per 200,000 Manhours
How to manage wellbore stability in the Vicking Graben tertiary shales by using mud systems environmentally friendly?
Authors: Charlez Ph. A. , Pradet V. , Onaisi A. , Gregoire M. 
Published: June 2009

Abstract
This paper deals with the drilling of the 17"1/2 section of the Dunbar field (Viking Graben - North Sea). In the past, this formation was systematically drilled with a conventional WBM in underbalanced conditions (mud weight less than formation pore pressure estimated at 1.4SG). With such a mud system, the well was highly unstable particularly in the Eocene shales (very large amounts of cavings were produced, calliper was very overgauged) and the final trip was particularly tight. Following three remedial side tracks experienced over the last two years, an extensive study has been carried out. The main recommendations were to drill the Eocene in overbalanced conditions (MW&gt;1.4SG) with a Silicate Mud. The results obtained on two wells slightly inclined (20° and 35° inclination at the 13"3/8 casing shoe) were very encouraging. By contrast to previous underbalanced experience, the hole was perfectly in gauge and trips much easier (regular wiper trips to be performed). However, even in the case of a perfectly stable rock and to ensure a good hole cleaning, the wells had to be circulated at a high rate and a sufficiently thick rheology.
These results have then been confirmed on a third well (64° at the 13"3/8 casing shoe) with a maximum mud weight equal to 1.45SG. However, this MW was not sufficient for 72° inclination (the well was too unstable and had to be abandoned).
Deterministic Versus Probabilistic Volume Estimates for Reservoirs Without a Known Downdip Limit
Authors: Jordan D. G. , Collarini C. R. 
Published: June 2009

Abstract
The Society of Petroleum Engineers and the World Petroleum Congresses issued revised reserve definitions in 1997 which allow reserves to be estimated using either deterministic or probabilistic methods.1 In the case of reservoirs defined by only a lowest-known hydrocarbon (LKH), the deterministic method limits the proved area to "the area defined by fluid contacts", i.e., the area above the LKH. Likewise, deterministically derived proved plus probable reserves are often considered to extend downdip to one sand thickness below the LKH, and there is little guidance on the limits of possible reserves. Probabilistic methods use 90%, 50%, and 10% confidence levels to determine proved, probable, and possible reserves, respectively, but with no guidance as to what distributions should be used.
Three reservoirs were examined and their estimated reservoir volumes compared using deterministic methods and probabilistic methods where various levels of information about the location of the reservoir limits were known. In certain cases, the estimated proved, probable, and possible volumes using the two methods varied significantly. Various distributions were used for the probabilistic methods, with significant variation in results.
Mesenchymal Stem Cells Prevent the Rejection of Fully Allogenic Islet Grafts by the Immunosuppressive Activity of Matrix Metalloproteinase-2 and -9
Authors: Ding Yunchuan , Xu Danmei , Feng Gang , Bushell Andrew , Muschel Ruth J. , Wood Kathryn J. 
Published: June 2009

OBJECTIVE
Mesenchymal stem cells (MSCs) are known to be capable of suppressing immune responses, but the molecular mechanisms involved and the therapeutic potential of MSCs remain to be clarified.

RESEARCH DESIGN AND METHODS
We investigated the molecular mechanisms underlying the immunosuppressive effects of MSCs in vitro and in vivo.

RESULTS
Our results demonstrate that matrix metalloproteinases (MMPs) secreted by MSCs, in particular MMP-2 and MMP-9, play an important role in the suppressive activity of MSCs by reducing surface expression of CD25 on responding T-cells. Blocking the activity of MMP-2 and MMP-9 in vitro completely abolished the suppression of T-cell proliferation by MSCs and restored T-cell expression of CD25 as well as responsiveness to interleukin-2. In vivo, administration of MSCs significantly reduced delayed-type hypersensitivity responses to allogeneic antigen and profoundly prolonged the survival of fully allogeneic islet grafts in transplant recipients. Significantly, these MSC-mediated protective effects were completely reversed by in vivo inhibition of MMP-2 and MMP-9.

CONCLUSIONS
We demonstrate that MSCs can prevent islet allograft rejection leading to stable, long-term normoglycemia. In addition, we provide a novel insight into the mechanism underlying the suppressive effects of MSCs on T-cell responses to alloantigen.
Immune Mediators in Patients With Acute Diabetic Foot Syndrome
Authors: Weigelt Christian , Rose Bettina , Poschen Ulrike , Ziegler Dan , Friese Gerd , Kempf Kerstin , Koenig Wolfgang , Martin Stephan , Herder Christian 
Published: June 2009

OBJECTIVE
Subclinical inflammation is an important risk factor for type 2 diabetes and diabetes complications. However, data on the association between inflammation and acute diabetic foot syndrome are scarce. The aim of this study was to compare systemic immune mediators in diabetic patients with and without an ulcer and to identify modulating factors.

RESEARCH DESIGN AND METHODS
Circulating levels of acute-phase proteins, cytokines, and chemokines were measured in diabetic patients with an ulcer (n = 170) and without an ulcer (n = 140). Of the patients, 88% had type 2 diabetes.

RESULTS
Patients with an acute foot ulcer had higher levels of C-reactive protein (CRP), fibrinogen, interleukin (IL)-6, macrophage migration inhibitory factor, macrophage inflammatory protein-1α, and interferon-γ–inducible protein-10 as well as lower levels of RANTES (regulated on activation normal T-cell expressed and secreted) (all P &lt; 0.01). No differences were found for IL-8, IL-18, and monocyte chemoattractant protein-1. Most of these associations persisted after adjustment for demographic and anthropometric data, metabolic confounders, and diabetes complications. In multivariate models, size of ulcer according to the University of Texas classification but not the grade of infection was independently associated with three markers of subclinical inflammation (CRP, IL-6, and fibrinogen).

CONCLUSIONS
We demonstrate in our cross-sectional study that acute foot ulcers and their severity are associated with a marked upregulation of acute-phase proteins, cytokines, and chemokines independently of the concomitant infection. Further studies should investigate whether an activation of the immune system precedes the development of foot ulcer and whether anti-inflammatory therapies might be effective.
Short-Term Aerobic Exercise Reduces Arterial Stiffness in Older Adults With Type 2 Diabetes, Hypertension, and Hypercholesterolemia
Authors: Madden Kenneth M. , Lockhart Chris , Cuff Darcye , Potter Tiffany F. , Meneilly Graydon S. 
Published: June 2009

OBJECTIVE
The relationship between increased arterial stiffness and cardiovascular mortality is well established in type 2 diabetes. We examined whether aerobic exercise could reduce arterial stiffness in older adults with type 2 diabetes complicated by comorbid hypertension and hyperlipidemia.

RESEARCH DESIGN AND METHODS
A total of 36 older adults (mean age 71.4 ± 0.7 years) with diet-controlled or oral hypoglycemic–controlled type 2 diabetes, hypertension, and hypercholesterolemia were recruited. Subjects were randomly assigned to one of two groups: an aerobic group (3 months vigorous aerobic exercise) and a nonaerobic group (no aerobic exercise). Exercise sessions were supervised by a certified exercise trainer three times per week, and a combination of cycle ergometers and treadmills was used. Arterial stiffness was measured using the Complior device.

RESULTS
When the two groups were compared, aerobic training resulted in a decrease in measures of both radial (−20.7 ± 6.3 vs. +8.5 ± 6.6%, P = 0.005) and femoral (−13.9 ± 6.7 vs. +4.4 ± 3.3%, P = 0.015) pulse-wave velocity despite the fact that aerobic fitness as assessed by Vo2max did not demonstrate an improvement with training (P = 0.026).

CONCLUSIONS
Our findings indicate that a relatively short aerobic exercise intervention in older adults can reduce multifactorial arterial stiffness (type 2 diabetes, aging, hypertension, and hypercholesterolemia).
Asian Americans: Diabetes Prevalence Across U.S. and World Health Organization Weight Classifications
Authors: Oza-Frank Reena , Ali Mohammed K. , Vaccarino Viola , Narayan K.M. Venkat 
Published: June 2009

OBJECTIVE
To compare diabetes prevalence among Asian Americans by World Health Organization and U.S. BMI classifications.

RESEARCH DESIGN AND METHODS
Data on Asian American adults (n = 7,414) from the National Health Interview Survey for 1997–2005 were analyzed. Diabetes prevalence was estimated across weight and ethnic group strata.

RESULTS
Regardless of BMI classification, Asian Indians and Filipinos had the highest prevalence of overweight (34–47 and 35–47%, respectively, compared with 20–38% in Chinese; P &lt; 0.05). Asian Indians also had the highest ethnic-specific diabetes prevalence (ranging from 6–7% among the normal weight to 19–33% among the obese) compared with non-Hispanic whites: odds ratio (95% CI) for Asian Indians 2.0 (1.5–2.6), adjusted for age and sex, and 3.1 (2.4–4.0) with additional adjustment for BMI.

CONCLUSIONS
Asian Indian ethnicity, but not other Asian ethnicities, was strongly associated with diabetes. Weight classification as a marker of diabetes risk may need to accommodate differences across Asian subgroups.
Third ventricle colloid cysts: a consecutive 12-year series
Authors: Mathiesen Tiit , Grane Per , Lindgren Lars , Lindquist Christer 
Published: June 2009

✓ A continuous follow-up review of colloid cysts including aspects of natural history and evaluation of treatment options is necessary to optimize individual treatment. Thirty-seven consecutive patients with colloid cyst of the third ventricle seen at Karolinska Hospital between 1984 and 1995 were reviewed. Five patients were admitted in a comatose state, and two died despite emergency ventriculostomy. Three had recurrent cysts following previous aspiration procedure. During the study period, patients underwent a total of 10 ventriculostomies, 10 aspirations, 26 microsurgical operations, and two shunt operations.
Twenty-four of 26 microsurgical operations were transcallosal and two were transcortical. Twenty-four operations (22 transcallosal and two transfrontal approaches) without permanent morbidity were performed by four surgeons. Transient memory deficit from forniceal traction was noted in 26%. The remaining two transcallosal operations, which led to permanent morbidity or mortality, were performed by two different surgeons. Aspiration of cysts performed by four different surgeons carried a 40% risk of transient memory deficit (10% permanent) and an 80% recurrence rate. One patient was found to be cured on radiological studies obtained at the 5-year follow-up review.
Seven cysts were followed by means of radiological studies with no treatment for 6 to 37 months. Five of these cysts grew, indicating that younger patients with colloid cysts will probably need surgical treatment.
The main causes of unfavorable results were: 1) failure to investigate symptoms that proved fatal; 2) subtotal resection; and 3) surgical complications. Transcallosal microsurgery produced excellent results when performed by experienced surgeons. A colloid cyst of the foramen of Monro is a disease that should be detected before permanent neurological damage has occurred. Permanent morbidity or mortality should not be accepted in modern series of third ventricle colloid cysts.
Medulloblastoma: is the 5-year survival rate improving?
Authors: David Karoly M. , Casey Adrian T. H. , Hayward Richard D. , Harkness William F. J. , Phipps Kim , Wade Angie M. 
Published: June 2009

✓ A series of 80 cases of medulloblastomas in children undergoing operation and postoperatively followed between 1980 and 1990 at Great Ormond Street Hospital for Children (GOSH) has been reviewed and compared to an earlier series reported from the same institution by McIntosh. The overall 5-year survival rate for the present series was 50%, although three patients died after surviving 5 years. The operative mortality rate was 5%. Survival analysis revealed that the presence or absence of spinal metastases and the necessity for some form of cerebrospinal fluid diversion within 30 days of the operation independently significantly affected survival in this series. Those patients with no spinal metastasis and total tumor removal had a 5-year survival rate of 73%, making this the most favorable subgroup in the series. Patient age and gender, duration of symptoms, Chang T stages, tumor volume, extent of resection, and postoperative chemotherapy were not significant variables.
Although these results are better than those reported in the earlier GOSH series, they are not significantly different from the results of the second 5-year cohort of patients described in that article. Radiotherapy remains the greatest advance in treatment, although it is hoped that further improvement will result from the various chemotherapy protocols now being studied and from increasing knowledge of the biological behavior of these tumors.
Utility of relative cerebral blood volume mapping derived from perfusion magnetic resonance imaging in the routine follow up of brain tumors
Authors: Siegal Tali , Rubinstein Rina , Tzuk-Shina Tzahala , Gomori John M. 
Published: June 2009

✓ It was recently demonstrated that imaging of brain tumors by relative cerebral blood volume (CBV) maps reconstructed from dynamic magnetic resonance (MR) data provide similar diagnostic information compared to positron emission tomography (PET) or 201Tl single-photon emission computerized tomography (201Tl-SPECT) scans. The authors used relative CBV mapping for routine follow-up evaluation of patients with brain tumors and compared its sensitivity to diagnostic MR imaging, 201Tl-SPECT and clinical assessment.
Fifty-nine patients were prospectively followed using 191 concomitant studies of dual section relative CBV maps, MR imaging, 201Tl-SPECT, and neurological evaluations. Studies were repeated every 2 to 3 months (median three evaluations/patient). The relative CBV maps were graded as relative CBV 0 to 4, where Grades 3 and 4 are indicative of proliferating tumors (four = rapid leak). There were 44 high-grade and 15 low-grade tumors followed during treatment. During the follow-up period a change in relative CBV grade was observed in 56% of the patients, revealing an increasing grade in 72% of them. The rapid leak phenomenon was detected in 35% of all studies and in 81% of those with a worsening relative CBV grade. Tumor progression was detected earlier by relative CBV maps as follows: earlier than MR imaging in 32% of the studies (earlier by a median of 4.5 months; p < 0.01); earlier than 201Tl-SPECT in 63% (median 4.5 months; p < 0.01), and earlier than clinical assessment in 55% (median 6 months; p < 0.01). In 82% of studies with positive MR imaging but negative 201Tl-SPECT, the lesions were smaller than 1.5 cm. The relative CBV maps clearly delineated the appearance of rapid leak in these lesions.
Routine use of relative CBV maps that can be implemented on any high-field MR unit and added to the regular MR evaluation provides useful functional information in patients with brain tumors. When used as an adjunct follow-up evaluation it proved more sensitive than the other modalities for early prediction of tumor growth. It is very sensitive to small regional changes, unlike functional imaging such as PET or SPECT scans. Based on previous experience with 76 regional CBV studies, the authors conclude that regional CBV mapping correlates with active tumor and it may separate enhancing scar and radiation injury from infiltrative tumor. A new effect named the rapid leak phenomenon was also observed; this phenomenon, as identified on the regional CBV maps, correlates with high malignancy.
Pathogenesis of Chiari malformation: a morphometric study of the posterior cranial fossa
Authors: Nishikawa Misao , Sakamoto Hiroaki , Hakuba Akira , Nakanishi Naruhiko , Inoue Yuichi 
Published: June 2009

✓ To investigate overcrowding in the posterior cranial fossa as the pathogenesis of adult-type Chiari malformation, the authors studied the morphology of the brainstem and cerebellum within the posterior cranial fossa (neural structures consisting of the midbrain, pons, cerebellum, and medulla oblongata) as well as the base of the skull while taking into consideration their embryological development. Thirty patients with Chiari malformation and 50 normal control subjects were prospectively studied using neuroimaging. To estimate overcrowding, the authors used a “volume ratio” in which volume of the posterior fossa brain (consisting of the midbrain, pons, cerebellum, and medulla oblongata within the posterior cranial fossa) was placed in a ratio with the volume of the posterior fossa cranium encircled by bony and tentorial structures. Compared to the control group, in the Chiari group there was a significantly larger volume ratio, the two occipital enchondral parts (the exocciput and supraocciput) were significantly smaller, and the tentorium was pronouncedly steeper. There was no significant difference in the posterior fossa brain volume or in the axial lengths of the hindbrain (the brainstem and cerebellum). In six patients with basilar invagination the medulla oblongata was herniated, all three occipital enchondral parts (the basiocciput, exocciput, and supraocciput) were significantly smaller than in the control group, and the volume ratio was significantly larger than that in the Chiari group without basilar invagination.
These results suggest that in adult-type Chiari malformation an underdeveloped occipital bone, possibly due to underdevelopment of the occipital somite originating from the paraxial mesoderm, induces overcrowding in the posterior cranial fossa, which contains the normally developed hindbrain. Basilar invagination is associated with a more severe downward herniation of the hindbrain due to the more severely underdeveloped occipital enchondrium, which further exacerbates overcrowding of the posterior cranial fossa.
Diagnosis of root avulsions in traumatic brachial plexus injuries: value of computerized tomography myelography and magnetic resonance imaging
Authors: Carvalho Gustavo Adolpho , Nikkhah Guido , Matthies Cordula , Penkert Götz , Samii Madjid 
Published: June 2009

✓ Surgical management and prognosis of traction injuries of the brachial plexus depend on the accurate diagnosis of root avulsion from the spinal cord. Myelography, computerized tomography (CT) myelography, and recently magnetic resonance (MR) imaging have become the main radiological methods for preoperative diagnosis of cervical root avulsions. Most of the previous studies on the accuracy of CT myelography and MR imaging studies have correlated the radiological findings with the extraspinal surgical findings at brachial plexus surgery. Surgical experience shows that in many cases extraspinal findings diverge from intradural determinations. Consequently, only correlation with the intradural surgical findings will allow assessment of the factual accuracy of CT myelography and MR imaging studies.In a prospective study, 135 cervical roots (C5–8) were evaluated by CT myelography and/or MR imaging and further explored intradurally via a hemilaminectomy. The accuracy of the preoperative CT myelography—based diagnosis in relation to the intraoperative findings was 85%. On the other hand, MR imaging demonstrated an accuracy of only 52%. The most common reasons for false-positive or false-negative findings were: 1) partial rootlet avulsion; 2) intradural fibrosis; and 3) dural cystic lesions. Computerized tomography myelography scans using 1- to 3-mm axial slices prove to be the most reliable method to evaluate preoperatively the presence of complete or partial root avulsion in traumatic brachial plexus injuries.Because extradural judgment of cervical root avulsion can be unreliable, accurate assessment of intraspinal root avulsion enormously simplifies the decision concerning the choice of donor nerves for transplantation and/or neurotization during brachial plexus surgery.