bluuebunny/crossref_metadata_2025 huggingface dataset:
Global justice: From theory to development action
Authors: Papaioannou Theo , Yanacopulos Helen , Aksoy Zuhre
Published: July 2009

One of the new forces likely to influence the future of global change and re‐shape development agendas is the growing theory and practice of global justice. The latter is founded upon the moral and political claim that, in today's globalising world, our duties and obligations to other persons extend beyond state borders. Two frontiers of the current theory and practice of global justice are poverty reduction and environmental sustainability. This paper draws on the discussion of the emerging theory and practice of global justice at the Development Studies Association conference 2008 on ‘Development's Invisible Hands’. However, the idea of global justice is a source of intentional action and the basis of social and political struggles, not an ‘invisible hand’ of development. The focus of the paper is on particular cases of campaigns in the field of poverty reduction and environmental sustainability such as the Jubilee 2000 Debt Cancellation campaign, Make Poverty History and the campaign for farmers' rights. The argument of the paper is that global justice is both a normative claim and an instrument of social and political action. This is clearly reflected in campaigns for and debates on extending the idea of fairness beyond state borders. Copyright © 2009 John Wiley & Sons, Ltd.
International development and belief in progress
Authors: Plant Stephen J.
Published: July 2009

Though interest in religious faith is growing in development studies, more needs to be done to show how faith commitments shape approaches to development. This paper models for non‐specialists ways in which the content of one particular faith tradition, the Christian tradition, might be brought to bear on development theory and practice. The particular issue explored is the belief in progress implicit in development. The paper argues that belief in the capacity of human beings to effect their own progress sits uneasily with the Christian tradition. It concludes that an authentically Christian account of hope may lead to a richer Christian understanding of the good of development. Copyright © 2009 John Wiley & Sons, Ltd.
The possibilities for and constraints on agency: Situating women's public and ‘hidden’ voices in Greater Buenos Aires
Authors: Tabbush Constanza
Published: July 2009

This paper focuses on women's possibilities for agency in an excluded neighbourhood of the suburbs of Buenos Aires, Argentina. In this urban location, while women's social and economic insecurity become part of public concerns and civil society demands for state action, other forms of women's physical vulnerability are sidelined from state institutions and cannot be voiced as social concerns. This paper tackles this paradox and analyses women's public and hidden narratives of participation, and identifies the social processes and institutional mechanisms by which certain needs of women are sidelined from the public sphere. Copyright © 2009 John Wiley & Sons, Ltd.
What's politics got to do with it?: Why donors find it so hard to come to terms with politics, and why this matters
Authors: Unsworth Sue
Published: July 2009

Donors are paying more attention to politics, and some are applying political analysis to specific aspects of development practice. But this is having little influence on mainstream debates about aid, and donors are not questioning their implicit assumptions about how development happens. There are powerful intellectual and institutional barriers to recognising that politics is central to the whole development process. This matters because, without a change in their mental models, donors will not invest in understanding local political dynamics, or give priority to strategically important but difficult issues. If they did so they would discover some very practical opportunities for progress. Copyright © 2009 John Wiley & Sons, Ltd.
Dynamics of microvascular remodelling during tumor growth in bone
Authors: Fuhrhop Ina , Schroeder Malte , Rafnsdóttir Svanheidur Loa , Viezens Lennart , Rüther Wolfgang , Hansen‐Algenstaedt Nils , Schaefer Christian
Published: July 2009

Microcirculatory properties of tumors have been shown to play a pivotal role in tumor progression and inefficacy of therapies. Although the influence of the microenvironment on angiogenesis has been intensively investigated in soft tissue tumors, little is known about the microvascular properties in bone metastasis. To determine the impact of the bone microenvironment on tumor growth and microcirculation we performed intravital microscopy using the “femur window” after implantation of red‐fluorescent‐protein‐transduced breast cancer cells into the femura of severe‐combined‐immunodeficient mice. Tumor size, functional vascular density, vessel diameter, and vessel distribution were quantified over 14 days. Tumor growth and microcirculation could be quantified at a high spatial resolution. Tumor progression was associated with a rapid remodeling process of the microcirculation within the tumor and the surrounding tissue. Although the total functional vascular density remained unaltered, we found a significant loss in small vessels and a concomitant increase in vascular diameter. The presented study demonstrates for the first time dynamics of morphological microcirculatory alterations of tumor growth in bone. The observed changes in tumor vascularization exhibit strong similarities to soft tissue tumors; however, the dynamics of vascular alterations are more rapid in the bone microenvironment. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:27–31, 2010
Quantification of D‐Asp and D‐Glu in rat brain and human cerebrospinal fluid by microchip electrophoresis
Authors: Huang Yong , Shi Ming , Zhao Shulin
Published: July 2009

A microchip electrophoresis (MCE) method with LIF detection was presented for quantification of D‐aspartic acid (D‐Asp) and D‐glutamate (D‐Glu) in biological samples. D‐Asp and D‐Glu were determined after precolumn derivatization with FITC. The chiral separation was performed on a glass/PDMS hybrid microfluidic chip using γ‐CD as chiral selector in the running buffer. High sensitive detection was obtained by the LIF detection. The LODs (S/N = 3) for D‐Asp and D‐Glu were 6.0×10–8 and 4.0×10–8 M, respectively. Using this method, the levels of D‐Asp and D‐Glu in rat brain and human cerebrospinal fluid (CSF) were determined.
RP–HPLC–ESI–MS characterization of novel peptide fragments related to rat parotid secretory protein in parasympathetic induced saliva
Authors: Ekström Jörgen , Murakami Masataka , Inzitari Rosanna , Khosravani Nina , Fanali Chiara , Cabras Tiziana , Fujita‐Yoshigaki Junko , Sugiya Hiorshi , Messana Irene , Castagnola Massimo
Published: July 2009

Two peptides (MW 1211.7 and 928.5 Da) were detected by RP–HPLC–ESI–MS analysis of parotid saliva secreted upon continuous parasympathetic stimulation. The peptide with the higher mass (PSPFr‐A) corresponded to the N‐terminal dodecapeptide (Fragment 1–12) of rat parotid secretory protein (PSP), while the peptide with the lower mass (PSPFr‐B) corresponded to the 4–12 fragment of the same protein. During stimulation, the PSPFr‐A secretion increased, while the PSPFr‐B secretion decreased (HPLC–ESI–MS). In the presence of cycloheximide, PSPFr‐A was not demonstrated, while the PSPFr‐B secretion decreased. In the presence of aprotinin, the PSPFr‐B secretion was almost abolished, while the PSPFr‐A secretion increased to higher levels than those observed in the absence of the inhibitor. In vitro perfusion, with artificial solution, of stimulated rat parotid glands excluded that the fragments were derived from the circulation. Neither peptide occurred in enriched granule preparations from unstimulated glands. The results suggest that at least two pathways – granular and vesicular – are responsible for the generation of the two peptides. PSPFr‐A is the first cleavage product in both pathways. PRPFr‐B is probably generated from granular PSPFr‐A only and, at the end of the granule mediated pathway, by the action of an enzyme of the serine protease class.
Determination of 25‐hydroxyvitamin D3 in human plasma using HPLC with UV detection based on SPE sample preparation
Authors: Kand'ár Roman , Žáková Pavla
Published: July 2009

Interest in the metabolism and physiological action of vitamin D is increased exponentially. The most important metabolites of vitamin D are 25‐hydroxyvitamin and 1,25‐dihydroxyvitamin D3. The aim of the study was to develop a rapid and simple HPLC method for the measurement of 25‐hydroxyvitamin D3 in human plasma. A method for the measurement of 25‐hydroxyvitamin D3 using HPLC with UV detection and investigation into the extraction techniques with regard to stability and recovery are described. For the separation, RP column LiChroCart 125‐4, Purospher RP‐18e, 5 μm, was used. The mixture of methanol and deionized water (95:5 v/v) was used as mobile phase. The analytical performance of this method is satisfactory: the intra‐ and inter‐assay coefficients of variation were below 10%. Quantitative recoveries from spiked plasma samples were between 92.0–103.2%. The LOD was 10 nmol/L. The preliminary reference range of 25‐hydroxyvitamin D3 in a group of blood donors is 62 ± 26 nmol/L.
ABO-incompatible deceased donor liver transplantation in the United States: A national registry analysis
Authors: Stewart Zoe A. , Locke Jayme E. , Montgomery Robert A. , Singer Andrew L. , Cameron Andrew M. , Segev Dorry L.
Published: July 2009

In the United States, ABO-incompatible liver transplantation (ILT) is limited to emergent situations when ABO-compatible liver transplantation (CLT) is unavailable. We analyzed the United Network for Organ Sharing database of ILT performed from 1990-2006 to assess ILT outcomes for infant (0-1 years; N = 156), pediatric (2-17 years; N = 170), and adult (> 17 years; N = 667) patients. Since 2000, the number of ILT has decreased annually, and there has been decreased use of blood type B donors and increased use of blood type A donors. Furthermore, ILT graft survival has improved for all age groups in recent years, beyond the improved graft survival attributable to era effect based on comparison to respective age group CLT. On matched control analysis, graft survival was significantly worse for adult ILT as compared to adult CLT. However, infant and pediatric ILTs did not have worse graft survival versus age-matched CLT. Adjusted analyses identified age-specific characteristics impacting ILT graft loss. For infants, transplant after 2000 and donor age < 9 years were associated with reduced risk of ILT graft loss. For pediatric patients, female recipient sex and donor age > 50 years were associated with increased risk of ILT graft loss. For adults, life support, repeat transplant, split grafts, and hepatocellular carcinoma were associated with increased risk of ILT graft loss. The current study identifies important trends in ILT in the United States in the modern immunosuppression era, as well as specific recipient, donor, and graft characteristics impacting ILT graft survival that could be utilized to guide ILT organ allocation in exigent circumstances. Liver Transpl 15:883–893, 2009. © 2009 AASLD.
The impact of consecutive operations on survival after liver transplantation
Authors: Halldorson Jeffrey B. , Bakthavatsalam Ramasamy , Reyes Jorge D. , Perkins James D.
Published: July 2009

The impact of surgeon fatigue on patient outcomes has not been previously studied. In order to assess the relationship of surgeon workload to patient outcome, we analyzed the impact of the interval between liver transplants and the cumulative number of liver transplants in a week on patient outcome. The outcomes of 390 liver transplants performed between 2003 and 2006 at the University of Washington Medical Center were analyzed. Overall 1-year patient/graft survival was significantly higher if the primary surgeon had >2 days between transplants (≤2 days between transplants, 82.8%/81.5%, versus >2 days between transplants, 92.5%/91.2%, P < 0.003/0.004). Patient survival was also improved if a surgeon performed ≤3 liver transplants in 1 week versus ≥4 (90.4% versus 80.9%, P < 0.026). No other analyzed complication reached significance. Surgeon fatigue from successive transplants may potentially affect liver transplant survival. Call schedules should recognize the potential impact of workload on liver transplant outcome. Liver Transpl 15:907–914, 2009. © 2009 AASLD.
Increased incidence of cytomegalovirus infection in high-risk liver transplant recipients receiving valganciclovir prophylaxis versus ganciclovir prophylaxis
Authors: Shiley Kevin T. , Gasink Leanne B. , Barton Todd D. , Pfeiffenberger Patrice , Olthoff Kim M. , Blumberg Emily A.
Published: July 2009

Optimal measures for the prevention of cytomegalovirus (CMV) in high-risk orthotopic liver transplant (OLT) patients are unknown. The charts of high-risk OLT recipients with 12 months of follow-up who were transplanted over a 44-month period were reviewed. The incidence of CMV disease in CMV-seropositive donor/CMV-seronegative recipient patients receiving valganciclovir or ganciclovir prophylaxis was compared. Sixty-six patients met the inclusion criteria and were treated with 1 of 3 prophylactic regimens: valganciclovir (900 mg daily; 27 patients), oral ganciclovir (1000 mg every 8 hours; 17 patients), or intravenous ganciclovir (6 mg/kg daily; 22 patients). Eight CMV cases occurred, all after completion of the prophylaxis. The combined incidence of CMV disease with intravenous and oral ganciclovir was lower than the incidence in valganciclovir recipients (P = 0.056; relative risk, 4.33; 95% confidence interval, 0.94–19.87). CMV disease occurred in 22.2% of valganciclovir recipients, 4.5% of intravenous ganciclovir recipients, and 5.9% of oral ganciclovir recipients. In conclusion, late-onset CMV disease occurred more frequently among high-risk liver transplant recipients treated with valganciclovir prophylaxis. The 4-fold higher incidence of CMV disease in our study supports the avoidance of valganciclovir for prophylaxis in high-risk OLT patients. Liver Transpl 15:963–967, 2009. © 2009 AASLD.
No evidence for systemic platelet activation during or after orthotopic liver transplantation
Authors: Pereboom Ilona T. A. , Adelmeijer Jelle , van Leeuwen Yvonne , Hendriks Herman G. D. , Porte Robert J. , Lisman Ton
Published: July 2009

Platelet function is thought to deteriorate during liver transplantation as a result of platelet activation and proteolysis of platelet receptors by plasmin following reperfusion. However, this hypothesis has never been formally tested. Twenty patients undergoing a first or second liver transplant were included in the study. Blood samples were taken at standardized time points during transplantation and up to 10 days after transplantation. Platelet activation was assessed by detection of the activation markers P-selectin and activated integrin αIIbβ3 with flow cytometry. Proteolytic cleavage of platelet receptors was assessed by flow cytometry measurement of the constitutively expressed platelet receptors glycoprotein Ibα and integrin αIIbβ3. In addition, using enzyme-linked immunosorbent assay techniques, we measured plasma levels of platelet activation products β-thromboglobulin and platelet factor 4 and plasma levels of cleaved fragments of glycoproteins Ibα and V. Flow cytometry analyses provided no evidence of substantial platelet activation during transplantation. In fact, the expression of activated integrin αIIbβ3 decreased postoperatively; this indicated that platelets were in a slightly activated state prior to surgery. Plasma levels of β-thromboglobulin and platelet factor 4 also substantially decreased after transplantation. In addition, no changes were observed in the constitutively expressed platelet receptors or in the plasma levels of platelet receptor fragments, and this indicated a lack of substantial receptor proteolysis. In conclusion, no evidence was found for significant activation of circulating blood platelets or the proteolysis of key platelet receptors during liver transplantation. These findings suggest that the platelet functional capacity does not decrease during liver transplantation. Liver Transpl 15:956–962, 2009. © 2009 AASLD.
An intention-to-treat analysis of liver transplantation for hepatocellular carcinoma using organ procurement transplant network data
Authors: Pelletier Shawn J. , Fu Sherry , Thyagarajan Veena , Romero-Marrero Carlos , Batheja Mashal J. , Punch Jeffrey D. , Magee John C. , Lok Anna S. , Fontana Robert J. , Marrero Jorge A.
Published: July 2009

Single-center studies have shown acceptable long-term outcomes following orthotopic liver transplantation (OLT) for hepatocellular carcinoma (HCC) when tumors are within the Milan criteria. However, the overall survival and waiting list removal rates have not been described at a national level with pooled registry data. To evaluate this, a retrospective cohort of patients listed for OLT with a diagnosis of HCC between January 1998 and March 2006 was identified from Organ Procurement Transplant Network data. Analysis was performed from the time of listing. Adjusted Cox models were used to assess the relative effect of potential confounders on removal from the waiting list as well as survival from the time of wait listing. A total of 4482 patients with HCC were placed on the liver waiting list during the study period. Of these, 65% underwent transplantation, and 18% were removed from the list because of tumor progression or death. The overall 1- and 5-year intent-to-treat survival for all patients listed was 81% and 51%, respectively. The 1- and 5-year survival was 89% and 61% for those listed with tumors meeting the Milan criteria versus 70% and 32% for those exceeding the Milan criteria (P < 0.0001). On multivariate analysis, advanced liver failure manifested by Child-Pugh class B or C increased the risk of death, while age < 55 years, meeting the Milan criteria, and obtaining a liver transplant were associated with better survival. The current criteria for liver transplantation of candidates with HCC lead to acceptable 5-year survival while limiting the dropout rate. Liver Transpl 15:859–868, 2009. © 2009 AASLD.
Liver transplantation at the extremes of the body mass index
Authors: Dick André A. S. , Spitzer Austin L. , Seifert Catherine F. , Deckert Alysun , Carithers Robert L. , Reyes Jorge D. , Perkins James D.
Published: July 2009

Controversies exist regarding the morbidity and mortality of patients undergoing liver transplantation at the extremes of the body mass index (BMI). A review of the United Network for Organ Sharing database from 1987 through 2007 revealed 73,538 adult liver transplants. Patients were stratified into 6 BMI categories established by the World Health Organization: underweight, <18.5 kg/m2; normal weight, 18.5 to <25 kg/m2; overweight, 25 to <30 kg/m2; obese, 30 to <35 kg/m2; severely obese, 35 to <40 kg/m2; and very severely obese, ≥40 kg/m2. Survival rates were compared among these 6 categories via Kaplan-Meier survival curves with the log-rank test. The underweight and very severely obese groups had significantly lower survival. There were 1827 patients in the underweight group, 1447 patients in the very severely obese group, and 68,172 patients in the other groups, which became the control. Groups with extreme BMI (<18.5 and ≥40) were compared to the control to assess significant differences. Underweight patients were more likely to die from hemorrhagic complications (P < 0.002) and cerebrovascular accidents (P < 0.04). When compared with the control, the very severely obese patients had a higher number of infectious complications and cancer events (P = 0.02) leading to death. In 3 different eras of liver transplantation, multivariable analysis showed that underweight and very severe obesity were significant predictors of death. In conclusion, liver transplantation holds increased risk for patients at the extremes of BMI. Identifying these patients and instituting aggressive new policies may improve outcomes. Liver Transpl 15:968–977, 2009. © 2009 AASLD.
Quantitative unique continuation for Neumann problems of elliptic equations with weight
Authors: Tao Xiangxing
Published: July 2009

Let P(ω, ∇) be an elliptic operator with weight ω, and let u be a solution in some Lipschitz domains to −P(ω, ∇u)+W∇u+Vu=0 with sharp singular potentials W and V. The weighted doubling estimates, the weighted three‐ball inequalities and the unique continuation at the boundary for solution u of the Neumann problem are established in this paper. Copyright © 2009 John Wiley & Sons, Ltd.
The Utility of Simulation in Medical Education: What Is the Evidence?
Authors: Okuda Yasuharu , Bryson Ethan O. , DeMaria Samuel , Jacobson Lisa , Quinones Joshua , Shen Bing , Levine Adam I.
Published: July 2009

Medical schools and residencies are currently facing a shift in their teaching paradigm. The increasing amount of medical information and research makes it difficult for medical education to stay current in its curriculum. As patients become increasingly concerned that students and residents are “practicing” on them, clinical medicine is becoming focused more on patient safety and quality than on bedside teaching and education. Educators have faced these challenges by restructuring curricula, developing small‐group sessions, and increasing self‐directed learning and independent research. Nevertheless, a disconnect still exists between the classroom and the clinical environment. Many students feel that they are inadequately trained in history taking, physical examination, diagnosis, and management. Medical simulation has been proposed as a technique to bridge this educational gap. This article reviews the evidence for the utility of simulation in medical education. We conducted a MEDLINE search of original articles and review articles related to simulation in education with key words such as simulation, mannequin simulator, partial task simulator, graduate medical education, undergraduate medical education, and continuing medical education. Articles, related to undergraduate medical education, graduate medical education, and continuing medical education were used in the review. One hundred thirteen articles were included in this review. Simulation‐based training was demonstrated to lead to clinical improvement in 2 areas of simulation research. Residents trained on laparoscopic surgery simulators showed improvement in procedural performance in the operating room. The other study showed that residents trained on simulators were more likely to adhere to the advanced cardiac life support protocol than those who received standard training for cardiac arrest patients. In other areas of medical training, simulation has been demonstrated to lead to improvements in medical knowledge, comfort in procedures, and improvements in performance during retesting in simulated scenarios. Simulation has also been shown to be a reliable tool for assessing learners and for teaching topics such as teamwork and communication. Only a few studies have shown direct improvements in clinical outcomes from the use of simulation for training. Multiple studies have demonstrated the effectiveness of simulation in the teaching of basic science and clinical knowledge, procedural skills, teamwork, and communication as well as assessment at the undergraduate and graduate medical education levels. As simulation becomes increasingly prevalent in medical school and resident education, more studies are needed to see if simulation training improves patient outcomes. Mt Sinai J Med 76:330–343, 2009. © 2008 Mount Sinai School of Medicine
Teaching Teamwork in Medical Education
Authors: Lerner Susan , Magrane Diane , Friedman Erica
Published: July 2009

Teamwork has become a major focus in healthcare. In part, this is the result of the Institute of Medicine report entitled To Err Is Human: Building a Safer Health System, which details the high rate of preventable medical errors, many of which are the result of dysfunctional or nonexistent teamwork. It has been proposed that a healthcare system that supports effective teamwork can improve the quality of patient care and reduce workload issues that cause burnout among healthcare professionals. Few clear guidelines exist to help guide the implementation of all these recommendations in healthcare settings. In general, training programs designed to improve team skills are a new concept for medicine, particularly for physicians who are trained largely to be self‐sufficient and individually responsible for their actions. Outside of healthcare, research has shown that teams working together in high‐risk and high‐intensity work environments make fewer mistakes than individuals. This evidence originates from commercial aviation, the military, firefighting, and rapid‐response police activities. Commercial aviation, an industry in which mistakes can result in unacceptable loss, has been at the forefront of risk reduction through teamwork training. The importance of teamwork has been recognized by some in the healthcare industry who have begun to develop their own specialty‐driven programs. The purpose of this review is to discuss the current literature on teaching about teamwork in undergraduate medical education. We describe the science of teams, analyze the work in team training that has been done in other fields, and assess what work has been done in other fields about the importance of team training (ie, aviation, nonmedical education, and business). Additionally, it is vital to assess what work has already been done in medicine to advance the skills required for effective teamwork. Much of this work has been done in fields in which medical professionals deal with crisis situations (ie, anesthesia, trauma, and labor and delivery). We describe the current programs for teaching medical students these essential skills and what recommendations have been made about the best ways to introduce teaching this skill set into the curriculum. Finally, we include a review on assessing teamwork because one cannot teach team training without implementing an assessment to ensure that the skills are being learned. Mt Sinai J Med 76:318–329, 2009. © 2008 Mount Sinai School of Medicine
A variational multiscale method to model crack propagation at finite strains
Authors: Mergheim J.
Published: July 2009

This contribution presents a hierarchical variational multiscale framework to model propagating discontinuities at finite strains. Thereby the deformation map is decomposed into coarse‐scale and fine‐scale displacements, which results in a decoupled system of coarse‐scale and fine‐scale equations. Both are solved numerically by means of the finite element method whereby crack propagation is taken into account at the fine scale. Growing cracks are numerically handled by the introduction of discontinuous elements. A locality assumption on the fine‐scale solution and an adaptive scheme to resize the fine‐scale domain are introduced and demonstrated to increase the efficiency of the method. Copyright © 2009 John Wiley & Sons, Ltd.
Flexible body dynamics in a local frame with explicitly predicted motion
Authors: Kawamoto A. , Krenk S. , Suzuki A. , Inagaki M.
Published: July 2009

This paper deals with formulation of dynamics of a moving flexible body in a local frame of reference. In a conventional approach the local frame is normally fixed to the corresponding body and always represents the positions and angles of the body: the positions and angles are represented by Cartesian coordinates and Euler angles or Euler parameters, respectively. The elastic degrees of freedom are expressed by, e.g. nodal coordinates in a finite element analysis, modal coordinates, etc. However, the choice of these variables as the generalized coordinates makes the resulting equations of motion extremely complicated. This is because the representation of the rotation of a body is highly non‐linear and this non‐linearity makes the coefficient matrices dependent on the coordinates themselves. In this paper, we propose an alternative way of treating the issue by explicitly predicting the body motions and regularly updating the local frame. First, the motion of the local frame is assumed to explicitly follow the associated moving body. Then, the equations of motion are derived in a set of generalized coordinates that express both rigid‐body and elastic degrees of freedom in the local frame. These equations are solved by a time integration with a given time interval. The motion of the local frame in the interval is estimated from a prediction of the rigid‐body motions. Then, the gap between the predicted and the actual motions is evaluated. Finally, the predictions are iteratively corrected by the obtained responses in the rigid‐body motions so that the gap should remain within an imposed tolerance. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and characterization of polyurethane cationomer/MMT hybrid composite
Authors: Buruiana Tinca , Melinte Violeta , Buruiana Emil C , Mihai Aura
Published: July 2009

BACKGROUND: The development of polymeric nanocomposites incorporating intercalated or exfoliated layered silicate clays into the organic matrix has been substantially motivated by the significant improvements induced by the presence of the inorganic component. Moreover, understanding and controlling the dispersion of inorganic layers into segmented polyurethane matrices by means of ionic interactions, and exploiting these interactions to enhance physicomechanical behaviour, could be of great interest in the field of polymer nanocomposites.

RESULTS: New cationic polyurethane elastomers were prepared starting from poly(butylene adipate)diol (Mn = 1000 g mol−1), 4,4′‐diphenylmethane diisocyanate, 1,4‐butanediol and N‐methyldiethanolamine or N,N′‐β‐hydroxyethylpiperazine, used as potential quaternizable moieties. The characterization of the polymers was achieved using specific analyses employed for the macromolecular samples (Fourier transform infrared and 1H NMR spectroscopy, thermogravimetric analysis (TGA), gel permeation chromatography). An extension of our research on polymers reinforced with organically modified montmorillonite (OM‐MMT) in order to prepare hybrid composites with improved properties was performed and the resulting materials were characterized using TGA, X‐ray diffraction, atomic force microscopy and scanning electron microscopy. Also, the mechanical properties of the cationic polyurethane/OM‐MMT composites were investigated in comparison with the pristine ionic/non‐ionic polymers and their composites containing non‐ionic polymer blended with OM‐MMT or ionic polymer and unmodified MMT.

CONCLUSION: The insertion of the organically modified clay into the polymeric matrix gave an improvement of the mechanical properties of the polyurethane composites, especially the tensile strength and stiffness of the hybrid materials. Copyright © 2009 Society of Chemical Industry
Quantitative risk assessment for the transport of ammonia by rail
Authors: Hassan C.R. Che , Puvaneswaran B. , Aziz A.R. , Zalina M. Noor , Hung F.C. , Sulaiman N.M.
Published: July 2009

Risk assessments are considered to be an essential tool in ensuring the safety of engineering projects. The benefits of using risks assessments have prompted its acceptance in the safety legislation for a number of industries. The use of quantitative risk assessment for rail transportation of hazardous materials has gained more attention in recent years, because the amount of the transported hazardous materials is large, and the transportation route often passes through populated areas, such as cities. In this study, the risk for the ammonia transportation by rail in Malaysia was conducted by combining the results from a previous failure frequency analysis and consequence analysis. The assessment results acknowledged the significant effects of train speeds on the overall individual risk. The risk with a tolerable risk limit of 1 × 10−6 per year increased significantly with more train accidents occurring at increasing speeds. Most of the surrounding populations along the transportation route analyzed are exposed to higher risk levels than the tolerable limit. This risk exposure to the public demonstrates the need for proper planning of moving ammonia through populated areas. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2010
A novel technique for nonlinear sensitivity analysis: application to moist predictability
Authors: Rivière O. , Lapeyre G. , Talagrand O.
Published: July 2009

A new nonlinear technique is described to compute the sensitivity of synoptic perturbation growth to environmental moisture. The perturbation growth is defined using a nonlinear generalization of singular vectors called Nonlinear Singular Vectors (NLSV). For a given atmospheric state evolving in time, the nonlinear sensitivity method consists in maximizing the growth rate of perturbations by seeking both the optimal NLSV perturbations and the most favorable spatial distribution of the moisture field. This results in a new atmospheric state that differs initially only by the water vapour field. The NLSV computed along this new state has the largest possible growth rate for all possible water vapour fields. We apply this method to a simulation of the moist primitive equations. For the particular case we study, we obtain a moistening of the lower troposphere and an amplification of energy of optimal perturbations three times larger than the amplification of optimal perturbations computed without altering the water vapour field. The optimal perturbations are similar to the perturbations of the unmodified water vapour case. A noteworthy property is that the complete saturation of the atmosphere leads to a smaller increase in amplification rate, which means that the water vapour field is strongly tied to the NLSV structure. Mechanisms explaining these results are discussed. This technique overcomes the limitations (in particular the linearity assumption) of moist singular vector analysis using moist norms or adjoint sensitivity analysis. It can be applied to diagnose sensitivity to other fields as well. Copyright © 2009 Royal Meteorological Society
Diagnostic procedures
Authors: McKean Joseph W. , Sheather Simon J.
Published: July 2009

Diagnostic procedures are used to check the quality of a fit of a model, to verify the validity of the assumptions behind the model, and to find outlying and/or highly influential observations. Our discussion focuses on the linear model (the most widely used model). Much of our discussion, however, pertains to other models, as we show when we extend our discussion to mixed models at the end of the paper. The traditional fit, least squares (LS), can be severely impaired by just one outlier. So along with LS we present two robust fits and diagnostic procedures which explore the differences among the three fits. These comparisons generally find the outlying and influential cases. Armed with this methodology, we then proceed to discuss diagnostics that explore the quality of fit and verify the validity of the assumptions, including independent and identically distributed errors and normality. Copyright © 2009 John Wiley & Sons, Inc.

This article is categorized under:

Statistical Models > Linear Models

Statistical and Graphical Methods of Data Analysis > Robust Methods

Statistical Models > Fitting Models

Statistical and Graphical Methods of Data Analysis > Statistical Graphics and Visualization
Prevalence of Hypothyroidism in Benign Breast Disorders and Effect of Thyroxine Replacement on the Clinical Outcome
Authors: Bhargav Panchagan R. K. , Mishra Anjali , Agarwal Gaurav , Agarwal Amit , Verma Ashok Kumar , Mishra Saroj Kanta
Published: July 2009

Background

The aim of this study was to determine the prevalence of hypothyroidism in patients with benign breast disorders (BBD). We then asked if thyroxine replacement in hypothyroid patients has any impact on the clinical outcome of the BBD.

Methods

This prospective study included 201 women with BBD. None of the included patients had previously suspected hypothyroidism. Clinical, laboratory, and follow‐up details of the patients were noted. Baseline serum thyroxine, thyroid‐stimulating hormone (TSH), and prolactin estimation was done in all cases. Thyroid peroxidase antibody (TPOAb) estimation was done in hypothyroid patients and/or patients with a goiter. In addition to the standard conservative management protocol, hypothyroid patients were given thyroxine replacement therapy. Their response to treatment was assessed at 3‐month intervals. The clinical outcomes of euthyroid and hypothyroid groups were compared.

Results

The mean age of the patients was 34 ± 8 years, and the mean length of follow‐up was 13.0 ± 4.2 months. The overall prevalence of hypothyroidism was 23.2% (nipple discharge 37%, mastalgia 23%, lump/lumpiness 17.4%). The rate of hypothyroidism and the mean serum TSH concentration were significantly higher among patients with nipple discharge than among those with mastalgia (P = 0.001) or a lump (P = 0.01). In all, 39% of hypothyroid women had TSH concentrations >10 mIU/l, and 53% had an elevated TPOAb titer. BBD symptoms were alleviated in 83% of the hypothyroid patients with only thyroxine replacement. The final clinical outcomes of hypothyroid patients with nipple discharge and mastalgia were significantly better than that of their euthyroid counterparts (P = 0.028 and 0.001, respectively); no significant difference was noted in patients with lumpiness (P = 0.144).

Conclusions

All women with BBD should be screened for hypothyroidism because the prevalence of hypothyroidism is high among this group and correction of hypothyroidism results in significant clinical improvement of BBD in most of these patients.
Minimally Invasive Surgical Treatment of Hepatocellular Carcinoma: Long‐Term Outcome
Authors: Lai Eric C. H. , Tang Chung Ngai , Yang George P. C. , Li Michael K. W.
Published: July 2009

Background

Laparoscopic liver resection for hepatocellular carcinoma (HCC) is still a matter of debate because of the uncertainty of the long‐term results and the fear of compromising the oncological resection. Published findings on survival and outcome after laparoscopic liver resection for HCC are scarce still. The aim of the present study was to report the perioperative and long‐term outcome of minimally invasive surgical treatment of HCC.

Methods

From January 1998 to November 2008, all patients with HCC who underwent laparoscopic liver resection in our unit were included. A prospectively collected database was analyzed retrospectively. Perioperative outcome included procedure‐related morbidity and mortality. Long‐term outcome included 5‐year overall survival and disease‐free survival.

Results

During the study period, 30 consecutive patients with HCC underwent laparoscopic liver resection (hand‐assisted laparoscopic liver resection, n = 22; total laparoscopic liver resection, n = 7; converted to open approach, n = 1). The mean tumor size was 2.8 cm. The mean operating time was 139.4 min, and 90% of patients had R0 resection and 10% of patients had R1 resection. The hospital mortality and morbidity rates were 0 and 20%, respectively. The mean hospital stay was 7.4 days. For those patients (n = 22) with a minimal follow‐up of 24 months, the 5‐year overall and disease‐free survival rates were 50 and 36%, respectively. No port site recurrence occurred.

Conclusions

This study showed that laparoscopic liver resection for HCC was feasible and safe in selected patients. The long‐term survival was also favorable.
Patients with Less Than Three Episodes of Diverticulitis May Benefit from Elective Laparoscopic Sigmoidectomy
Authors: Rotholtz Nicolas A. , Montero Miguel , Laporte Mariano , Bun Maximiliano , Lencinas Sandra , Mezzadri Norberto
Published: July 2009

Background

This study was designed to asses the predictive factors of postoperative complications in patients who underwent a laparoscopic elective approach for recurrent diverticulitis and to determine the relationship between the number of acute episodes and surgical morbidity.

Methods

A retrospective analysis was performed on patients with colonic diverticular disease treated by an elective laparoscopic approach between July 2000 and November 2007. The variables studied were age, sex, BMI, ASA, number of previous acute episodes, local severity, abdominal surgery history, comorbidity, and laparoscopic training of the surgeon. Logistic regression analysis was used to establish significant results.

Results

A total of 137 patients were analyzed; 87 (63.5%) were men with a mean age of 56.7 (range, 27–89) years. Intraoperative and postoperative complications occurred in 2.9% (n = 4) and 12.4% (n = 17) of the patients respectively. Conversion rate was 9.4% (n = 13). Local severity (odds ratio (OR), 16.34; 95% confidence interval (CI), 4.1–64.5, p = 0.00007), history of abdominal surgery (OR, 3.02; 95% CI, 0.8–11.5; p = 0.02), and the training of the operating surgeon (OR, 4.8; 95% CI, 1.02–22.7; p = 0.001) were significant risk factors related to surgery conversion. A history of three or more acute episodes was significantly associated with a high severity of local process and was a risk factor related to conversion (OR, 2.6; 95% CI, 0.5–12.3; p = 0.22). The severity of the local process seems to be a risk factor for perioperative complications. A significant association (χ2, 4.45; p = 0.03) between conversion and postoperative complications also was observed (OR: 3.79, 95% CI, 1.02–14.07; p = 0.04).

Conclusions

A history of three or more acute episodes of diverticulitis with conservative treatment is associated with a high severity of the local process during laparoscopic sigmoidectomy and increases the rate of conversion and perioperative complications.
Preparation of Monodisperse Iron Oxide Nanoparticles via the Synthesis and Decomposition of Iron Fatty Acid Complexes
Authors: Chen Chih-Jung , Lai Hsin-Yi , Lin Chee-Cheng , Wang Jiun-Shen , Chiang Ray-Kuang
Published: July 2009

Iron fatty acid complexes (IFACs) are prepared via the dissolution of porous hematite powder in hot unsaturated fatty acid. The IFACs are then decomposed in five different organic solvents under reflux conditions in the presence of the respective fatty acid. The XRD analysis results indicate that the resulting NPs comprise a mixture of wustite, magnetite, and maghemite phases. The solvents with a higher boiling point prompt the formation of larger NPs containing wustite as the major component, while those with a lower boiling point produce smaller NPs with maghemite as the major component. In addition, it is shown that unstable NPs with a mixed wustite–magnetite composition can be oxidized to pure maghemite by extending the reaction time or using an oxidizing agent.
Substance use and abuse trajectories across adolescence: A latent trajectory analysis of a community‐recruited sample of girls
Authors: Marti C. Nathan , Stice Eric , Springer David W.
Published: July 2009

We used data from a school‐based study of 496 adolescent girls to identify qualitatively distinct substance use and substance abuse developmental trajectory groups and tested whether the problematic groups differed from the non‐problematic groups on baseline and outcome validation variables. Results identified four substance use groups (late users, normative users, late‐heavy users, early‐heavy users) and four substance abuse groups (non‐abusers, moderate‐escalating abusers, moderate decreasing abusers, adolescent‐limited heavy abusers). Problematic substance use and abuse trajectory groups, relative to non‐problematic groups, showed elevations in baseline validation variables (age 14 delinquency, depressive symptoms, negative affectivity, parental support deficits, body dissatisfaction) and outcome validation variables (age 20 delinquency, depressive symptoms, social impairment, legal problems, school dropout, and substance abuse diagnosis), providing partial validation of this trajectory model.
Psychosocial, mechanical, and metabolic factors in adolescents’ musculoskeletal pain in multiple locations: A cross‐sectional study
Authors: Paananen Markus V. , Auvinen Juha P. , Taimela Simo P. , Tammelin Tuija H. , Kantomaa Marko T. , Ebeling Hanna E. , Taanila Anja M. , Zitting Paavo J. , Karppinen Jaro I.
Published: July 2009

Recent studies indicate that adolescents often experience musculoskeletal pains in two or more body locations. However, previous studies have mainly focused on localized pains, and the determinants of multiple musculoskeletal pains in adolescents are not well known. The present study was set to evaluate the role of psychosocial, mechanical, and metabolic factors in adolescents’ musculoskeletal pains in multiple locations. The study population consisted of the 1986 Northern Finland Birth Cohort; 15‐ to 16‐year‐old adolescents (n=6986), who responded to a mailed questionnaire in 2001. We assessed the associations of emotional and behavioral problems, physical activity, sitting time, sleeping time, overweight and smoking with musculoskeletal pains using multinomial logistic regression. Multiple pains were common, 23% of boys and 40% of girls reported feeling pain in at least three locations over the past 6 months. These pains were not only associated with anxious/depressed symptoms, withdrawn/depressed symptoms, somatic complaints, rule‐breaking and aggressive behavior, social problems, thought and attention problems, but also with high physical activity level, long sitting time, short sleeping time and smoking, among both boys and girls. In addition, pain in three to four locations associated with overweight in girls. A high number of psychosocial, mechanical and metabolic factors associated strongly with multiple pains. In conclusion, multiple musculoskeletal pains were strongly associated with psychosocial complaints, but also with mechanical and metabolic factors. Reported musculoskeletal pains in multiple locations in adolescence may have both peripheral (trauma, decreased regenerative ability) and central (sensitivity) causes.
Reciprocal influence on the incidence of symptoms in trigeminally and spinally innervated areas
Authors: Marklund Susanna , Wiesinger Birgitta , Wänman Anders
Published: July 2009

Temporomandibular disorders (TMD), headaches, and spinal pain show co‐morbidity and may therefore influence each other. The hypothesis tested is that the presence of any of these conditions will increase the risk of onset of new symptoms within a 2‐year period. The study population comprised 280 dental students, who were examined three times at 12‐month intervals. The incidence was calculated for a 2‐year period, based on subjects without the defined symptom at baseline. Each participant was classified into five different case‐control groups, representing incidence cases or no incidence (controls) of: (1) nonpain TMD symptoms; (2) jaw pain; (3) headaches; (4) spinal pain; and (5) TMD pain. Presence of headaches and of spinal pain and signs and symptoms of TMD at baseline were used as independent variables in logistic regression analyses, controlling for age and sex. Incidence cases with TMD pain reported spinal pain at baseline significantly more often than the controls, and were mostly women. Incidence cases with headaches and incidence cases with jaw pain significantly more often had signs of TMD and reported spinal pain at baseline, compared to controls. Incidence cases with nonpain TMD symptoms or spinal pain significantly more often presented with signs of TMD at baseline. Our findings show that pain and dysfunction in trigeminally innervated areas and pain in spinally innervated areas mutually predict the onset of new symptoms in dental students, indicating common pathophysiological mechanisms and individual vulnerability. This may be of importance in risk assessment and treatment planning of individuals with musculoskeletal pain.