bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrogenerated Chemiluminescence Sensor Based on a Self‐Assembled Monolayer of Ruthenium(II)‐bis(2,2′‐bipyridyl)(aminopropyl imidazole) on Gold Deposited Screen Printed Electrode
Authors: Kang Chang Hoon , Choi Young‐Bong , Kim Hyug‐Han , Choi Han Nim , Lee Won‐Yong
Published: July 2011

A new electrogenerated chemiluminescence (ECL) sensor based on a self‐assembled monolayer (SAM) of Ru(II)‐bis(2,2′‐bipyridyl)(aminopropyl imidazole) on a gold‐deposited screen printed electrode (SPE) has been developed. Since the ECL emission of the Ru(II)‐bis(2,2′‐bipyridyl)(aminopropyl imidazole) complex can be easily obtained at an applied potential of less than +0.8 V, the possibility of the oxidation of the Ru‐complex SAM formed on gold‐deposited SPE electrode surface was greatly diminished and thus the stability of the resulting Ru‐complex SAM‐based ECL sensor was enormously enhanced compared to the previously reported Ru(bpy)32+‐derivative monolayer‐based ECL sensors with applied potentials of more than +1.0 V. In the present study, the gold deposited SPE with carbon nanotube paste was used in order to increase the amount of Ru‐complex immobilized on the electrode surface through a large surface area of deposited gold nanoparticles causing good charge transport and thus leading to the increased sensitivity of the ECL sensor. The ECL characteristics obtained with the present Ru‐complex SAM‐based ECL sensor are compared with those obtained with other Ru(bpy)32+‐SAM‐based ECL sensors.
Mesoporous amine‐bridged polysilsesquioxane for CO2 capture
Authors: Qi Genggeng , Fu Liling , Duan Xiaonan , Choi Brian Hyun , Abraham Michael , Giannelis Emmanuel P.
Published: August 2011

A novel class of amine‐supported sorbents based on amine‐bridged mesoporous polysilsesquioxane was developed via a simple one‐pot sol‐gel process. The new sorbent allows the incorporation of a large amount of active groups without sacrificing surface area or pore volume available for CO2 capture, leading to a CO2 capture capacity of 3.2 mmol g−1 under simulated flue gas conditions. The sorbent is readily regenerated at 100°C and exhibits good stability over repetitive adsorption‐desorption cycling. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd
Conditional deletion of Bmpr1a in differentiated osteoclasts increases osteoblastic bone formation, increasing volume of remodeling bone in mice
Authors: Okamoto Mina , Murai Junko , Imai Yuuki , Ikegami Daisuke , Kamiya Nobuhiro , Kato Shigeaki , Mishina Yuji , Yoshikawa Hideki , Tsumaki Noriyuki
Published: July 2011

Bone undergoes remodeling consisting of osteoclastic bone resorption followed by osteoblastic bone formation throughout life. Although the effects of bone morphogenetic protein (BMP) signals on osteoblasts have been studied extensively, the function of BMP signals in osteoclasts has not been fully elucidated. To delineate the function of BMP signals in osteoclasts during bone remodeling, we deleted BMP receptor type IA (Bmpr1a) in an osteoclast-specific manner using a knock-in Cre mouse line to the cathepsin K locus (CtskCre/+;Bmpr1aflox/flox, designated as Bmpr1aΔOc/ΔOc). Cre was specifically expressed in multinucleated osteoclasts in vivo. Cre-dependent deletion of the Bmpr1a gene occurred at 4 days after cultivation of bone marrow macrophages obtained from Bmpr1aΔOc/ΔOc with RANKL. These results suggested that Bmpr1a was deleted after formation of osteoclasts in Bmpr1aΔOc/ΔOc mice. Expression of bone-resorption markers increased, thus suggesting that BMPRIA signaling negatively regulates osteoclast differentiation. Trabeculae in tibia and femurs were thickened in 3.5-, 8-, and 12-week-old Bmpr1aΔOc/ΔOc mice. Bone histomorphometry revealed increased bone volume associated with increased osteoblastic bone-formation rates (BFR) in the remodeling bone of the secondary spongiosa in Bmpr1aΔOc/ΔOc tibias at 8 weeks of age. For comparison, we also induced an osteoblast-specific deletion of Bmpr1a using Col1a1-Cre. The resulting mice showed increased bone volume with marked decreases in BFR in tibias at 8 weeks of age. These results indicate that deletion of Bmpr1a in differentiated osteoclasts increases osteoblastic bone formation, thus suggesting that BMPR1A signaling in osteoclasts regulates coupling to osteoblasts by reducing bone-formation activity during bone remodeling. © 2011 American Society for Bone and Mineral Research
Advantages of isovolemic hemodilution‐red cell exchange therapy to prevent recurrent stroke in sickle cell anemia patients
Authors: Sarode Ravi , Matevosyan Karén , Rogers Zora R. , Burner James D. , Rutherford Cynthia
Published: July 2011

Chronic simple hypertransfusion (every 3 to 4 weeks) effectively prevents secondary stroke in children with sickle cell anemia but leads to iron overload despite chelation therapy. Conventional red blood cell exchange (C‐RBCx) has advantages over simple transfusion: no net iron gain and less frequent hospital visits. However, C‐RBCx requires more red blood cell units, an apheresis instrument and skilled personnel; it is also more expensive. We developed a modified procedure where isovolemic hemodilution precedes RBCx (IHD‐RBCx) to decrease RBC units required and to increase the interval between procedures. Twenty patients underwent IHD‐RBCx over a period of 7 years. IHD‐RBCx required 11% fewer RBC units and increased inter‐procedure interval from 37 to 53 days compared to C‐RBCx. The median number of annual procedures decreased from 9.8 to 7.0 per patient, resulting in estimated savings of more than $4.5 million over 10 years for 20 patients while providing improved care. Five patients have discontinued chelation therapy; three while on C‐RBCx and two while on IHD‐RBCx. No adverse events occurred related to the isovolemic hemodilution phase and no patients had recurrent stroke. IHD‐RBCx is a safe, efficient, and cost effective therapy for secondary prevention of stroke in patients with sickle cell anemia. J. Clin. Apheresis, 2011. © 2011 Wiley‐Liss, Inc.
Serum amyloid‐A levels in neonatal necrotizing enterocolitis
Authors: Eras Zeynep , Oğuz Suna , Dizdar Evrim Alyamac , Sari Fatma Nur , Dilmen Uğur
Published: July 2011

We aimed to evaluate serum levels of serum amyloid‐A (SAA) both in the diagnosis and monitoring the treatment response of necrotizing enterocolitis (NEC). Forty‐five preterm neonates were enrolled in the study, including 15 infants with NEC, 15 with sepsis, and 15 healthy preterm infants. Pre‐ and posttreatment serum SAA levels were measured. Among patients with NEC, 11 had stage 1 and 4 had stage 2 disease according to the modified Bell's staging criteria. Baseline SAA levels of the infants with NEC were significantly higher than controls (P=0.013) and were significantly lower than those with sepsis (P=0.004). When infants with stage 1and stage 2 NEC were analyzed separately, baseline SAA levels of the infants with stage 2 NEC were significantly higher than controls (P=0.027) than those with stage 1 NEC (P=0.018), but similar to those with sepsis. There was a trend that baseline SAA levels were also correlated with the Bell stage (r=0.501, P=0.057). Posttreatment SAA levels significantly decreased in infants with sepsis (P=0.002). Pre‐ and posttreatment SAA levels were similar in patients with stage 1 and 2 NEC. In conclusion, SAA rises in early stages of NEC and may aid in diagnosis as a serum marker. J. Clin. Lab. Anal. 25:233–237, 2011. © 2011 Wiley‐Liss, Inc.
Unusual false‐positive case of urinary screening for buprenorphine
Authors: Lippi Giuseppe , Romero Araelsis , Cervellin Gianfranco , Mercadanti Mariella
Published: July 2011

Buprenorphine is a centrally acting analgesic drug that is administered for the management of opioid dependence and as an analgesic drug for the treatment of chronic pain. The growing use of this substance has determined an increased need for laboratory testing for either detection and confirmation of the illicit use or monitoring compliance as a substitution therapy for opioid dependence. We describe here the case of urinary sample adulteration with exogenous buprenorphine (6,952 ng/ml), which has led to afalse‐positive immunoassay test result (14.9 ng/ml) on a subsequent sample due to a phenomenon of instrumental carry‐over. This unusual case confirms the importance to take into account adulteration when screening urines for buprenorphine in patients undergoing substitution therapy for opioid dependence, routinely perform a confirmation assay on positive samples, and rule out instrumental carry‐over. J. Clin. Lab. Anal. 25:244–245, 2011. © 2011 Wiley‐Liss, Inc.
Evaluation of α‐iduronidase in dried blood spots is an accurate tool for mucopolysaccharidosis I diagnosis
Authors: Müller Karen B. , Pereira Vanessa G. , Martins Ana M. , D'Almeida Vânia
Published: July 2011

Background: Mucopolysaccharidosis type I (MPS I) is caused by a deficiency of the α‐L‐iduronidase (IDUA), which leads to the accumulation of glycosaminoglycans in lysosomes. MPS I patients present a spectrum ranging from a severe to an attenuated phenotype. Once clinical suspicion is present, diagnosis of MPS I can be performed by enzyme activity determination and/or molecular analysis. The aim of this study was to establish a reference interval value to IDUA activity using a dried blood spots (DBS) assay and to evaluate whether this assay could be a secure tool to diagnose MPS I patients. Results: IDUA activity range on HV DBS samples were 1.40–7.78 µmol/l blood/hr. Regarding the validation group, 11 of the 36 individuals clinically suspected of MPS I had the diagnosis confirmed by DBS and reference assay (leukocytes). When we considered the new proposed cutoff value of 1.5 µmol/l blood/hr, the sensitivity, specificity, and predictive values were 100%. Conclusions: Our results strongly suggest that the determination of IDUA activity using a DBS assay is a secure tool for MPS I diagnosis. However, it is extremely important to assure that all recommendations for collection, transport, and storage are correctly followed to guarantee the quality of the samples. J. Clin. Lab. Anal. 25:251–254, 2011. © 2011 Wiley‐Liss, Inc.
Serum paraoxonase‐1 activities and oxidative status in patients with plaque‐type psoriasis with/without metabolic syndrome
Authors: Usta Murat , Turan Enver , Aral Hale , Inal Berrin Bercik , Gurel Mehmet Salih , Guvenen Guvenc
Published: July 2011

Objective: Psoriasis is a chronic immune‐mediated inflammatory skin disease associated with metabolic syndrome, which is made up of a cluster of disorders, including obesity, diabetes mellitus, dyslipidemia, and cardiovascular disease. The aim of this study was to investigate serum paraoxonase‐1 activities and oxidative status parameters in patients with plaque‐type psoriasis with or without metabolic syndrome. Methods: In this study, patients with plaque‐type psoriasis with (n=25) or without (n=27) metabolic syndrome, according to the criteria of the International Diabetes Federation (IDF), were matched for age and sex to an equally sized control group (n=25). Results: In patients without metabolic syndrome, serum paraoxonase and arylesterase activities showed mean decreases of 29 and 6%, respectively, whereas in patients with metabolic syndrome, the mean decreases in the enzymes' activities were 35 and 11%, respectively, compared with those in the control group. Serum total antioxidant capacity and total oxidant status were not statistically significant in any of the three groups. Multiple linear regression analysis revealed that HDL cholesterol and log‐transformed triglyceride were independent variables for serum arylesterase activity and that fasting glucose and diastolic blood pressure were independent variables for serum paraoxonase activity. Conclusions: These results suggest that according to the criteria of the IDF, the significant decrease observed in serum paraoxonase activity was independent of the metabolic syndrome in patients with mild‐to‐moderate plaque‐type psoriasis, whereas the significant decrease in serum arylesterase activity was associated with the metabolic syndrome. J. Clin. Lab. Anal. 25:289–295, 2011. © 2011 Wiley‐Liss, Inc.
Cutoff level to detect heterozygous alpha 1 antitrypsin deficiency in Turkish population
Authors: Simsek Halis , Pinar Aslı , Altinbas Akif , Alp Alparslan , Balaban Yasemin H. , Buyukasik Yahya , Ozcebe Osman , Hascelik Gulsen , Gedikoglu Gokhan , Tatar Gonca
Published: July 2011

Background: Alpha 1 antitrypsin (AT) deficiency is a hereditary disorder leading to the defective defence system against neutrophil elastasis in lung and accumulation of insoluble heterodimer AT molecules in hepatocytes. Knowledge of the prevalence of AT deficiency in each country is important to organize the public health policy. The aim of this study is to determine the prevalence of AT deficiency in Turkish population and to define the cutoff value of AT level in serum to detect heterozygous AT deficient subjects. Materials and Methods: Serum samples from 1,203 healthy blood donors were used, attending the Blood Bank of Hacettepe Medical Faculty. Isoelectric focusing method for determining PIM, PIS, and PIZ alleles and rate immune nephelometry for measuring the level of AT in serum were used. Results: Out of 1,203 healthy blood donors enrolled, 1,164 (%96.8) had normal variant PI MM allelee, 9 (%0.7) PI MZ, 7 (%0.6) PI MS, 6 (%0.5) MF, and 17 (%1.4) PI M? (unidentified variants with existing standards). Most individuals (89.6%) with low AT level (cutoff <100 mg/dl) in serum were positive for PI MM allele. The cutoff value to investigate PI MZ was 100.5 mg/dl, which had PPV and NPV of 5.0 and 99.9%, respectively. AT deficiency is a rare hereditary disorder in asymptomatic healthy Turkish blood donors. Although the cutoff value of 100.5 mg/dl for AT level in serum was able to detect heterozygous AT deficiency in the healthy population, this finding should be conformed to case‐control studies. J. Clin. Lab. Anal. 25:296–299, 2011. © 2011 Wiley‐Liss, Inc.
Detection of the JAK2 mutation in myeloproliferative neoplasms by asymmetric PCR with unlabeled probe and high‐resolution melt analysis
Authors: Cao Hong‐Cui , Lin Jiang , Qian Jun , Yao Dong‐Ming , Li Yun , Yang Jing , Chen Qin , Chai Hai‐Yan , Xiao Gao‐Fei
Published: July 2011

Background: Several methods have been established to detect the JAK2 V617F mutation, a frequent event involved in the pathogenesis of myeloproliferative neoplasms (MPNs). High‐resolution melt (HRM) analysis is a newly established technique without the requirement of any gel‐based post‐PCR handling. Methods: An asymmetric PCR with unlabeled specific probe was developed and combined to HRM analysis o screen for JAK2 V617F mutation. Results: Heterozygous mutation was easily distinguished from homozygous JAK2 for the obvious shape change. Homozygous JAK2 mutant can be also well separated from wild‐type JAK2 in the presence of internal temperature calibrators. The easily recognizable and maximal sensitivity of HRM analysis was 5% for the detection of JAK2 V617F mutation, higher than 25% of direct sequencing. In the test of blind screening of 223 samples (111 Ph− MPNs, 60 Ph+ chronic myeloid leukemia, and 52 acute myeloid leukemia), JAK2 V617F mutations were found in 78 (70%) patients with MPNs, but in none with chronic and acute myeloid leukemia. HRM analysis of all cases was fully concordant with the results of PCR‐RFLP and direct sequencing. Conclusions: The HRM method with unlabeled probe could be used as convenient, sensitive and reliable diagnostic test for detection of JAK2 V617F mutation. J. Clin. Lab. Anal. 25:300–304, 2011. © 2011 Wiley‐Liss, Inc.
A pollen record of the last 450 years from a lowland peat bog on Tristan da Cunha, South Atlantic, implying early anthropogenic influence
Authors: Ljung Karl , Björck Svante
Published: July 2011

A pollen diagram from a small peat bog on the island of Tristan da Cunha in the central South Atlantic (37°05'S,12°17'W) is presented. The pollen diagram contains data from both introduced and native plant taxa. The earliest pollen grains from introduced Plantago lanceolata are dated to around AD 1570, and probably represent unintentional introductions of weeds by the earliest Portuguese explorers visiting the islands. After AD 1600, a greater abundance of pollen from introduced plants and declining tree pollen values indicate opening of the lowland vegetation and more intense land use, probably attributable to the effect of seasonal seal and whale hunters. After AD 1800, evidence of increased erosion and more intense land use are inferred from the pollen diagram, reflecting permanent settlement. Copyright © 2011 John Wiley & Sons, Ltd.
Quality changes in sea urchin (Strongylocentrotus nudus) during storage in artificial seawater saturated with oxygen, nitrogen and air
Authors: Wang Chao , Xue Changhu , Xue Yong , Li Zhaojie , Lv Yingchun , Zhang Hao
Published: August 2011

BACKGROUND: Sea urchin gonads are highly valued seafood that degenerates rapidly during the storage period. To study the influence of dissolved oxygen concentration on quality changes of sea urchin (Strongylocentrotus nudus) gonads, they were stored in artificial seawater saturated with oxygen, nitrogen or air at 5 ± 1 °C for 12 days.

RESULTS: The sensory acceptability limit was 11–12, 6–7 and 7–8 days for gonads with oxygen, nitrogen or air packaging, respectively. Total volatile basic nitrogen (TVB‐N) values reached 22.60 ± 1.32, 32.37 ± 1.37 and 24.91 ± 1.54 mg 100 g−1 for gonads with oxygen, nitrogen or air packaging at the points of near to, exceeding and reaching the limit of sensory acceptability, indicating that TVB‐N values of about 25 mg 100 g−1 should be regarded as the limit of acceptability for sea urchin gonads. Relative ATP content values were 56.55%, 17.36% and 18.75% for gonads with oxygen, nitrogen or air packaging, respectively, on day 2. K‐values were 19.37%, 25.05% and 29.02% for gonads with oxygen, nitrogen or air packaging, respectively, on day 2. Both pH and aerobic plate count values showed no significant difference (P > 0.05) for gonads with the three treatments.

CONCLUSION: Gonads with oxygen packaging had lower sensory demerit point (P < 0.05) and TVB‐N values (P < 0.05), and higher relative ATP content (P < 0.01) and K‐values (P < 0.05), than that with nitrogen or air packaging, with an extended shelf life of 4‐5 days during storage in artificial seawater at 5 ± 1 °C. Copyright © 2011 Society of Chemical Industry
Movements of white‐tailed deer in riparian habitat: Implications for infectious diseases
Authors: Clements Gregory M. , Hygnstrom Scott E. , Gilsdorf Jason M. , Baasch David M. , Clements Myndi J. , Vercauteren Kurt C.
Published: July 2011

Movements of male white‐tailed deer (Odocoileus virginianus) are of great concern with respect to spread of chronic wasting disease (CWD) across landscapes because most yearlings males disperse and adult males have higher prevalence of CWD than do females and younger deer. We radiocollared and monitored 85 male white‐tailed deer in the middle Missouri River Valley of eastern Nebraska and western Iowa, USA from 2004 to 2008. Average size (±SE) of fixed‐kernel annual home ranges (95%) and core areas (50%) for resident deer were 449 (±32) ha and 99 (±7) ha, respectively. Resident deer exhibited a high‐degree of fidelity to their home ranges. Mean overlap between consecutive annual home ranges and core areas was 81% and 74%, respectively. Average dispersal distance was 17.7 ± 4.5 km (range = 3–121 km) for 22 radio‐marked and 6 ear‐tagged yearlings. Mean spring dispersal distance (25 km) was 150% greater than fall (10 km). Dispersal direction from Desoto National Wildlife Refuge (DNWR) was bimodal on a northwest to southeast axis that followed the Missouri River corridor. Of 22 yearlings that dispersed, 18 (82%) established adult home ranges within the river valley. Dispersal movements of yearling males represent the greatest risk for rapid spread of diseases from infected source populations. Disease management efforts in riparian habitats should target male fawns and yearling males for removal in areas within or immediately adjacent to river corridors. © 2011 The Wildlife Society.
Synthesis, characterization, and computational modeling of benzodithiophene donor–acceptor semiconducting polymers
Authors: Sista Prakash , Hao Jing , Elkassih Sussana , Sheina Elena E. , Biewer Michael C. , Janesko Benjamin G. , Stefan Mihaela C.
Published: July 2011

Donor–acceptor semiconducting polymers containing benzodithiophene with decyl phenylethynyl substituents have been synthesized. Density functional calculations on the polymers' band gaps and frontier orbitals energies provide reasonable agreement with cyclic voltammetry, photoelectron spectroscopy, and UV–vis absorption measurements. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Synthesis, molecular, and morphological characterization of initial and modified diblock copolymers with organic acid chloride derivatives
Authors: Politakos Nikolaos , Weinman Craig J. , Paik Marvin Y. , Sundaram Harihara S. , Ober Christopher K. , Avgeropoulos Apostolos
Published: July 2011

Six well defined PS‐b‐PB1,2 diblock copolymers (PS: polystyrene and PB: polybutadiene) with almost 100% of 1,2 microstructure for the PB segment were synthesized. Size exclusion chromatography (SEC), membrane osmometry (MO) and proton nuclear magnetic resonance spectroscopy (1H NMR) were used for verification of the molecular characteristics and the 100% ‐1,2 addition for the PB blocks. Modification with heptanoyl or pentadecafluorooctanoyl chloride was accomplished via hydroboration and subsequent oxidation, leading to hydroxylated PB blocks and was verified with 1H NMR and Fourier transform infrared (FTIR) spectroscopy. Only two samples were modified with both organic acid chloride derivatives. Structural characterization was accomplished via transmission electron microscopy (TEM) and small‐angle X‐ray scattering (SAXS) in all cases. The self‐assembly was more evident in the modified copolymers with the corresponding halides due to the increase of the molecular weight of the modified PB block. Taking into consideration the χN values in each case and comparing the results with those of PS‐b‐PI copolymers already reported in the literature the discrepancies with the theoretical predictions are very small or minimal. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
The Spitsbergen South Cape tip jet
Authors: Reeve Mathew A. , Kolstad Erik W.
Published: July 2011

We investigated low‐level tip jets generated at the southern tip of the island of Spitsbergen, part of the Svalbard archipelago in the Arctic. Low‐level tip jets occur in many locations where airflow converges around obstacles, such as islands. They are often poorly resolved in forecasts or re‐analyses, so it is important to document their locations and shed light on why they occur. Tip jets are the result of flow stagnation and flow splitting upstream of an obstacle; both of these processes are dependent on the stability of the air column, wind speed and direction upstream. Jets generated around Sørkapp, the southern cape of Spitsbergen, have been resolved previously in numerical studies, but no climatology exists. In this study, we used the Weather Research and Forecasting model (WRF) to demonstrate the influence of topography on the development of tip jets. We used QuikSCAT satellite‐derived surface wind data to identify tip jet events and compile climatologies, and the ERA‐Interim data to investigate the prevailing synoptic conditions during jet events and identify the main driving forces.

We found that tip jets can occur throughout the year, associated with a negative surface‐level pressure anomaly moving in a northeast direction from the Norwegian Sea and towards the Barents Sea. On average, jets occurred just over 8% of days throughout the year. The maximum 60‐day running mean of occurrence was around 12% and occurred between February and March. The results showed that negative wind speed and positive static stability anomalies were statistically significant upstream of the island group. These anomalies remain significant when seasons of high, middle and low occurrence were analysed separately. We conclude therefore that wind direction persistence may play an important role in the seasonality of jet occurrences in the study region. Copyright © 2011 Royal Meteorological Society
Exploring middle school students' conceptions of the relationship between genetic inheritance and cell division
Authors: Williams Michelle , DeBarger Angela Haydel , Montgomery Beronda L. , Zhou Xuechun , Tate Erika
Published: August 2011

This study examines students' understanding of the normative connections between key concepts of cell division, including both mitosis and meiosis, and underlying biological principles that are critical for an in‐depth understanding of genetic inheritance. Using a structural equation modeling method, we examine middle school students' understanding of these relationships. A total of 209 seventh‐grade students participated in this study and completed a technology‐enhanced unit on genetics. Content‐based assessments were administered to all students. Findings from a confirmatory factor analysis supplemented with an analysis of students' responses revealed a strong relationship between the concepts of genetic inheritance and cell division and provided evidence of the nature of the difficulties that students have when trying to understand these concepts. Specifically, students were challenged to demonstrate an integrated understanding of the differences between mitosis and meiosis processes. Also some students struggled to explain the importance of these processes as they relate to passage of genetic information. This study offers the science education field further insight into younger students' learning about genetic inheritance and informs the design of effective science learning materials at the middle school level. © 2011 Wiley Periodicals, Inc. Sci Ed 96:78–103, 2012
Subgroup identification based on differential effect search—A recursive partitioning method for establishing response to treatment in patient subpopulations
Authors: Lipkovich Ilya , Dmitrienko Alex , Denne Jonathan , Enas Gregory
Published: July 2011

We propose a novel recursive partitioning method for identifying subgroups of subjects with enhanced treatment effects based on a differential effect search algorithm. The idea is to build a collection of subgroups by recursively partitioning a database into two subgroups at each parent group, such that the treatment effect within one of the two subgroups is maximized compared with the other subgroup. The process of data splitting continues until a predefined stopping condition has been satisfied. The method is similar to ‘interaction tree’ approaches that allow incorporation of a treatment‐by‐split interaction in the splitting criterion. However, unlike other tree‐based methods, this method searches only within specific regions of the covariate space and generates multiple subgroups of potential interest. We develop this method and provide guidance on key topics of interest that include generating multiple promising subgroups using different splitting criteria, choosing optimal values of complexity parameters via cross‐validation, and addressing Type I error rate inflation inherent in data mining applications using a resampling‐based method. We evaluate the operating characteristics of the procedure using a simulation study and illustrate the method with a clinical trial example. Copyright © 2011 John Wiley & Sons, Ltd.
Multiple imputation for completion of a national clinical audit dataset
Authors: Cattle Brian A. , Baxter Paul D. , Greenwood Darren C. , Gale Christopher P. , West Robert M.
Published: July 2011

The Myocardial Ischaemia National Audit Project (MINAP) is a register of heart attacks covering 234 acute admitting hospitals in England and Wales. It is used to assess the extent to which hospitals are attaining the government targets for patients with heart attacks (myocardial infarction). MINAP is therefore of national importance in coronary care and of potential international importance for research. As with most observational databases, there is missing data in MINAP, which has the potential to bias statistical analyses. In this paper, we use multiple imputation to reduce the impact of missing data and we give details of how our imputation scheme was implemented. The key contribution of this paper is the provision of multiply completed datasets, suited to a range of analyses, that can be used to make efficient inferences without the distractions of missing data. Our work will assist MINAP in achieving its priority goal of providing useful data with which to analyse patient care. Copyright © 2011 John Wiley & Sons, Ltd.
cDNA microarray analysis of the gene expression of murine leukemia RAW 264.7 cells after exposure to propofol
Authors: Wu Rick Sai‐Chuen , Liu Kuo‐Ching , Tang Nou‐Ying , Chung Hsiung‐Kwang , Ip Siu‐Wan , Yang Jai‐Sing , Chung Jing‐Gung
Published: July 2011

Propofol (2,6‐diisopropylphenol) is the most extensively used general anesthetic‐sedative agent and it is employed in clinical patients. It has been shown that propofol exhibits anticancer activities. However, there is no available information to address propofol‐induced cytotoxic effects and affected gene expressions on murine leukemia cells. Therefore, we investigated the effects of propofol on the levels of protein and gene expression, which are associated with apoptotic death in mouse leukemia RAW 264.7 cells in vitro. Results indicated that propofol induced cell morphological changes, cytotoxicity, and induction of apoptosis in RAW 264.7 cells in vitro. Western blot analysis demonstrated that propofol promoted Fas, cytochrome c, caspase‐9 and −3 active form and Bax levels, but inhibited Bcl‐xl protein level which led to cell apoptosis. Furthermore, cDNA microarray assay indicated that propofol significantly enhanced 5 gene expressions (Gm4884; Gm10883; Lce1c; Lrg1; and LOC100045878) and significantly suppressed 26 gene expressions (Gm10679; Zfp617; LOC621831; LOC621831; Gm5929; Snord116; Gm3994; LOC380994; Gm5592; LOC380994; Gm4638; LOC280487; Gm4638; Tex24; A530064D06Rik; BC094916; EG668725; Gm189; Hist2h3c2; Gm8020; Snord115; Gm3079; Olfr198; Tdh; Snord115; and Olfr1249). Based on these observations, propofol‐altered apoptosis‐related proteins might result from induction of apoptotic gene expression and inhibition of cell growth gene expression, which finally led to apoptosis in a mouse leukemia cell line (RAW 264.7) in vitro. © 2011 Wiley Periodicals, Inc. Environ Toxicol 28: 471–478, 2013.
Emergence and refinement
Authors: Sanders J. W. , Smith Graeme
Published: August 2011

Emergent behaviour—system behaviour not determined by the behaviours of system components when considered in isolation—is commonplace in multi-agent systems, particularly when agents adapt to environmental change. This article considers the manner in which Formal Methods may be used to authenticate the trustworthiness of such systems. Techniques are considered for capturing emergent behaviour in the system specification and then the incremental refinement method is applied to justify design decisions embodied in an implementation. To demonstrate the approach, one and two-dimensional cellular automata are studied. In particular an incremental refinement of the ‘glider’ in Conway’s Game of Life is given from its specification.
Stop bugging me: An examination of adolescents’ protection behavior against online harassment
Authors: Lwin May O. , Li Benjamin , Ang Rebecca P.
Published: July 2011

Online harassment is a widespread phenomenon with consequential implications, especially for adolescents, who tend to engage in high‐risk behavior online. Through the use of Protection Motivation Theory (PMT), we examine the predictors motivating the intention of youths to adopt protection behavior against online harassment. A survey was conducted with 537 youths from a stratified sample in Singapore. Regression analyses showed that perceived severity of online harassment, response efficacy and self efficacy of online protective behavior were significant predictors of behavioral intention with varying weights. The sole exception was perceived susceptibility to online harassment, which did not significantly predict behavioral intention. Gender and age were also found to moderate adolescents’ uptake of protective behavior. The results suggest that public service programs targeted at educating youths should aim to increase coping appraisals and emphasize the severity of online harassment. Targeted educational programs could include those aimed at specific age or gender groups.
Body image as a mediator of non‐suicidal self‐injury in adolescents
Authors: Muehlenkamp Jennifer J. , Brausch Amy M.
Published: July 2011

Attitudes towards the body have been largely overlooked as a potential risk factor for adolescent non‐suicidal self‐injury (NSSI) despite theorizing that a negative body image may play a critical role in the development of this behavior. The current study used structural equation modeling to evaluate the fit of a theoretical model specifying body image as a mediator between negative affect and NSSI in a combined clinical and non‐clinical sample of 284 adolescents. The data supported the model, accounted for 21.6% of the variance in NSSI, and body image significantly mediated the relationship between negative affect and NSSI. These findings provide essential preliminary evidence that body image may represent a necessary but not sufficient risk factor for NSSI in adolescents and that treatment for NSSI should consider targeting body‐related pathology in addition to emotion regulation. The findings also support including body image within developing etiological models of NSSI.
Testicular Microlithiasis, Long Term Experience of a Single Institution
Authors: Kimuli Michael , Beckley Ian , Cast James , Cooksey Graeme
Published: July 2011

Introduction:

Several studies have reported an association between testicular microlithiasis (TML) and testicular malignancy with some suggesting the concordance to be as high as 40%. In 2000, we published a large study of 4819 patients referred for scrotal ultrasound (USS) at four referral centers. Based on our findings we recommended ultrasound surveillance of patients with TML. The aim of this study was to determine the long-term outcome of our surveillance regimen.

Methods:

We reviewed the prospective database of all men diagnosed with TML at USS between 1996 and 2006 at our institution. All patients diagnosed with TML were scheduled for six-monthly USS and in addition they were given instructions to perform regular self-examination. Fifteen years after the surveillance program was commenced, all patients were contacted and asked to complete a short questionnaire.

Results:

57 men were diagnosed with TML with no concurrent or previous testicular tumour. The mean period of follow up was 28.4 months (3–102). Only one man developed testicular cancer during the follow up period.

Conclusions:

We currently recommend regular testicular self-examination of all men with TML and reserve USS surveillance for selected patients with associated risk factors for testicular malignancy.
Erectile Dysfunction following Radical Prostatectomy: A Review
Authors: Pantelides Nicholas M. , Agrawal Sachin , Poullis Chris , Chetwood Andrew , Winkler Mathias H.
Published: July 2011

Radical prostatectomy remains the gold-standard treatment for localised prostate cancer. Despite the widespread introduction of nerve-sparing techniques, post-operative erectile dysfunction (ED) is still a significant source of morbidity. There are multiple approaches to prevent and treat ED. Recent refinements to surgical technique attempt to minimise disruption to the prostatic neural and arterial supply. A greater understanding of the factors affecting ED has also enabled the first multi-variate risk stratification model, thereby potentially improving awareness of pre-operative risk. Numerous on-demand treatments are available, including phosphodiesterase type 5 inhibitors, intracavernous/transurethral alprostadil, vacuum erection devices and combination therapy with multiple agents. As our understanding of the aetiology improves, attempts to manipulate the molecular mechanisms underpinning ED are also being investigated. In addition, early pharmacological rehabilitation is used to preserve cavernosal smooth muscle function until intra-operative neurapraxia resolves, although the optimum regimen is yet to be defined. Currently, much work is ongoing to improve our understanding and treatment of post-prostatectomy ED. We review the current status and recent advances in this field.
Person-Centered Care — Ready for Prime Time
Authors: Ekman Inger , Swedberg Karl , Taft Charles , Lindseth Anders , Norberg Astrid , Brink Eva , Carlsson Jane , Dahlin-Ivanoff Synneve , Johansson Inga-Lill , Kjellgren Karin , Lidén Eva , Öhlén Joakim , Olsson Lars-Eric , Rosén Henrik , Rydmark Martin , Sunnerhagen Katharina Stibrant
Published: July 2011

Long-term diseases are today the leading cause of mortality worldwide and are estimated to be the leading cause of disability by 2020. Person-centered care (PCC) has been shown to advance concordance between care provider and patient on treatment plans, improve health outcomes and increase patient satisfaction. Yet, despite these and other documented benefits, there are a variety of significant challenges to putting PCC into clinical practice. Although care providers today broadly acknowledge PCC to be an important part of care, in our experience we must establish routines that initiate, integrate, and safeguard PCC in daily clinical practice to ensure that PCC is systematically and consistently practiced, i.e. not just when we feel we have time for it. In this paper, we propose a few simple routines to facilitate and safeguard the transition to PCC. We believe that if conscientiously and systematically applied, they will help to make PCC the focus and mainstay of care in long-term illness.
Denial of pain relief during labor to parturients in southeast Nigeria
Authors: Chigbu Chibuike O. , Onyeka Tonia C.
Published: July 2011

Objective

To evaluate the experiences of parturients with regard to pain relief during labor in Enugu, Nigeria.

Methods

Women attending the prenatal clinics of 3 maternity care centers were interviewed via pre‐tested interviewer‐administered questionnaires between August 2010 and January 2011. Both open and closed questions were asked to evaluate the opinions and experiences of the respondents with regard to labor analgesia in previous pregnancies.

Results

Overall, 34.1% of respondents were aware of their right to labor pain relief. Only 33.5% of maternal requests for labor pain relief were granted. Women who did not request labor analgesia indicated ignorance and fear of labor caregivers as their major reasons.

Conclusion

Most women in southeast Nigeria are unaware of their right to pain relief in labor. Ignorance and fear of unfavorable reactions from labor caregivers are hindering women from requesting labor analgesia. There is a need to address the issue of refusal of maternal requests for labor pain relief because it constitutes a violation of the fundamental right of the parturient and an unnecessary breach of medical ethics.
Pudendal thigh flap in the treatment of acquired gynatresia from caustic pessaries
Authors: Ugburo Andrew O. , Mofikoya Bolaji O. , Oluwole Ayodeji A. , Fadeyibi Idowu O. , Abidoye Gbadegesin
Published: July 2011

Objectives

To evaluate the use of vaginoplasty with the pudendal thigh flap in patients with gynatresia caused by herbal pessaries in a multidisciplinary context.

Methods

The study included patients with herbal‐pessary‐induced vaginitis and gynatresia. Surgical treatment consisted of vaginoplasty with the pudendal thigh flap; patients with associated fibroids had a myomectomy during the same setting. The severity of the stenosis and the outcome after surgery were assessed with rating scales devised for the present study.

Results

The study included 21 patients (mean age 36.05 ± 1.69 years, range 18–50 years). The most common reason for herbal pessary use was fibroids with infertility. Prior to presentation, most patients had already undergone a median of 2 procedures involving vaginal adhesiolysis and dilatations without improvement. In total, 17 (80.9%) patients underwent surgery. Of these, 6 (35.3%) presented with both fibroids and gynatresia. Before surgery, all patients had poor sexual function with apareunia. Postoperatively, 11 (64.7%) patients reported painless sexual intercourse.

Conclusion

Joint management by plastic surgeons and gynecologists using the pudendal thigh flap for vaginoplasty in caustic gynatresia resulted in a functional vagina. Simultaneous myomectomy and vaginoplasty in patients with fibroids and gynatresia was safe.
A population‐based register study to determine indications for episiotomy in Finland
Authors: Räisänen Sari , Vehviläinen‐Julkunen Katri , Gisler Mika , Heinonen Seppo
Published: July 2011

Objective

To evaluate whether there is a shift in the episiotomy target group from women at low risk to those at high risk of obstetric anal sphincter injuries, concomitant with a decrease in the use of episiotomy.

Methods

A population‐based register of 514 741 women with singleton vaginal deliveries recorded in the Finnish Medical Birth Register was reviewed. Primiparous and multiparous women with episiotomy were compared to women without episiotomy for possible risk factors via stepwise logistic regression analysis. The prevalence and risk of episiotomy were evaluated over 5 time periods from 1997 to 2007.

Results

The occurrence of episiotomy decreased from 71.5% in 1997–1999 to 54.9% in 2006–2007 among primiparous women, and from 21.5% in 1997–2001 to 9.2% in 2006–2007 among multiparous women. The use of episiotomy decreased in not only low‐risk but also high‐risk women who had operative vaginal or breech deliveries, macrosomic newborns, and oxytocin augmentation. The ratio of episiotomy use remained relatively unchanged in different subgroups even though episiotomy policy became increasingly restrictive over time.

Conclusions

The spectrum of episiotomy indications has not changed over time, and use of episiotomy has declined arbitrarily to a similar extent among high‐ and low‐risk women.
Medical, ethical, and legal considerations in fertility preservation
Authors: Shah Divya K. , Goldman Edward , Fisseha Senait
Published: July 2011

The past 2 decades have seen a significant rise in cancer survival rates, and an increasing proportion of survivors at reproductive age are interested in childbearing. Although assisted reproduction provides physicians with an array of potential possibilities to help patients whose fertility is compromised by cancer treatment, there is still a dearth of regulation regarding the application of this technology. The present paper reviews the current options for fertility preservation, with a particular focus on the legal and ethical challenges that confront providers of this type of care.
Occupational health in health care workers
Authors: Hofmann Friedrich , Stößel Ulrich
Published: July 2011

Since the second half of the 20th century occupational health in health care workers is a well-established part of occupational medicine. Identification of environmental, biological, chemical, physical, and psychosocial hazards has lead to a number of preventive measures: Technical (e.g. use of safe instruments and double gloving as protection) and immunological (vaccinations) measures against biological hazards), and technical (lifting aides) and personal (back-schools) intervention to prevent musculoskeletal disorders are well-designed examples.
National determinants of international preferences in post-communist Europe: The case of Slovakia in the European Union
Authors: Rybář Marek
Published: July 2011

This paper shows that the dominant theory of European integration, the liberal inter-governmentalism, contains several assumptions about the process and character of national preference formation that may not be fully met in the post-communist EU member states. It argues that the primacy of economic and societal interests in influencing positions of national governments should not be taken for granted. Using Slovakia as an example, it demonstrates the autonomy of political and bureaucratic actors and importance of their preferences. It is also argued that ideational and exogenous factors should not be left out in constructing a realistic framework of national preference formation.
The Emergence of Timbre: Ligeti's Synthesis of Electronic and Acoustic Music in Atmosphères
Authors: IVERSON JENNIFER
Published: August 2011

In 1957, soon after his emigration from Hungary, György Ligeti began an internship at the electronic music studio of Westdeutscher Rundfunk (WDR) in Cologne. The three electronic works Ligeti produced there constitute a small portion of his oeuvre, but it is commonly acknowledged that his experiences in the studio were crucial for his stylistic development. This article makes specific analytical connections between the techniques of elektronische Musik that Ligeti encountered at the WDR and his sound-mass techniques in acoustic composition. The discourses in circulation in the electronic studio of the 1950s – especially as articulated by Karlheinz Stockhausen, Karel Goeyvaerts, and Gottfried Michael Koenig – reveal a collective obsession with gaining compositional control over timbre. By internalizing and reusing mainstream elektronische Musik techniques such as additive synthesis, filtering, and Bewegungsfarbe in an acoustic form, Ligeti brought timbre forward as the central compositional problem in the acoustic work Atmosphères.
Fast micro Hall effect measurements on small pads
Authors: Westergaard Østerberg Frederik , Hjorth Petersen Dirch , Nielsen Peter F. , Rosseel Erik , Vandervorst Wilfried , Hansen Ole
Published: August 2011

Sheet resistance, carrier mobility, and sheet carrier density are important parameters in semiconductor production, and it is therefore important to be able to rapidly and accurately measure these parameters even on small samples or pads. The interpretation of four-point probe measurements on small pads is non-trivial. In this paper we discuss how conformal mapping can be used to evaluate theoretically expected measurement values on small pads. Theoretical values calculated from analytical mappings of simple geometries are compared to the values found from the numerical conformal mapping of a square onto the infinite half-plane, where well-established solutions are known. Hall effect measurements are performed to show, experimentally, that it is possible to measure Hall mobility in less than one minute on squares as small as 70 × 70 μm2 with a deviation of ±6.5% on a 1σ level from accurate reference measurements, when only small sheet resistance variations are present. For samples with a sheet resistance variation of more than 5%, a more time consuming method must be used. Here, the theoretically expected measurement values are computed based on the sheet resistance variation using a finite element method. This more accurate method has an experimental repeatability of ±1.6% even on inhomogeneous samples.
Direct observation of fatigue in epitaxially grown Pb(Zr,Ti)O3 thin films using second harmonic piezoresponse force microscopy
Authors: Murari Nishit M. , Hong Seungbum , Lee Ho Nyung , Katiyar Ram. S.
Published: August 2011

Here, we present a direct observation of fatigue phenomena in epitaxially grown Pb(Zr0.2Ti0.8)O3 (PZT) thin films using second harmonic piezoresponse force microscopy (SH-PFM). We observed strong correlation between the SH-PFM amplitude and phase signals with the remnant piezoresponse at different switching cycles. The SH-PFM results indicate that the average fraction of switchable domains decreases globally and the phase delays of polarization switching differ locally. In addition, we found that the fatigue developed uniformly over the whole area without developing region-by-region suppression of switchable polarization as in polycrystalline PZT thin films.