bluuebunny/crossref_metadata_2025 huggingface dataset:
Sensitivity Analysis of Weight Reduction Results of an Observational Cohort Study in Overweight and Obese Children and Adolescents in Germany: the EvAKuJ Study
Authors: Böhler Thomas , Goldapp Cornelia , Mann Reinhard , Reinehr Thomas , Bullinger Monika , Holl Reinhard , Hoffmeister Ulrike , van Egmond-Fröhlich Andreas , Ravens-Sieberer Ulrike , Wille Nora , Westenhöfer Joachim , Bengel Jürgen
Published: October 2013

In the German EvAKuJ observational cohort study, changes in the body mass index standard deviation score (BMI-SDS) of overweight and obese children and adolescents as primary outcome of multimodal (short, inpatient or long, outpatient) weight-loss interventions are difficult to interpret. Published intention-to-treat (ITT) and per protocol data obtained at the end of the intervention (T1), one year (T2), and two years (T3) after its end were used for sensitivity analysis of treatment success rates. The odds ratio and the number needed to treat (NNT) for BMI-SDS reduction of at least −0.2 (successful treatment) and at least −0.5 (good treatment success) were related to spontaneous BMI-SDS reduction rates in a hypothetical control group (control event rate, CER). At T1, treatment seems to be effective up to a CER of 10% in inpatients and of 5% in outpatients. ITT analysis, compromised by a loss to follow-up of 81 to 90% (inpatients) and 57 to 66% (outpatients), indicated that treatment may become less effective at a CER above 1% in inpatients (e.g., successful treatment at T2: NNT=106, at T3: NNT=51), and above 5% in outpatients (successful treatment at T2: NNT=7, at T3: NNT=8; good treatment success at T2 and T3: NNT=25). Positive short-term effects of inpatient treatment of overweight and obese children and adolescents may not be maintained in the long term. Long-term effectiveness of outpatient treatment may depend on age and the degree of overweight.
Evaluation of progress with using community conversation as a strategy to encourage district level abandonment of female genital mutilation and/or cutting in 10 districts in Ethiopia
Authors: Alem Ellen , Hailu Emezat , Siyoum Haile-leul , Sesay Ibrahim , Mitik Lulit , Suyama Maki , Kibur Martha , Pearson Roger
Published: October 2013

Background: Female genital mutilation and/or cutting (FGM/C), whilst widespread, is declining in Ethiopia; 81% of 45–49-year-old women were circumcised in a 2005 survey, and 62%of 15–19-year-olds.Objectives: This evaluation examined progress in abandoning FGM/C in ten woredas(districts) where strategy based on the social convention theory had led to official declarations of abandonment and assessed if the strategy could accelerate the declining trend of the FGM/C practice in Ethiopia.Method: Quantitative and qualitative instruments collected data from a document review, a household survey (1275 households), in-depth and key informant interviews and focus group discussions.Results: Overall, there were encouraging results in terms of awareness creation and behavioural change to some extent. Sixty-nine percent of women and 41% of girls interviewed perceived a decline in the practice (range 40% – 90%) after the declaration. Seventy-six percent of women said they would not circumcise girls in the future. The involvement of influential people such as religious leaders, elders, health extension workers, and law enforcement officials in the teaching contributed immensely to the awareness creation. However, some districts reports indicated the practice had gone underground. The costs of facilitating the strategy varied from USD 3 to 7 per person, with better results where costs were higher. The abandonment events tended to costaround 25% of total costs, an area where cost efficiency can be improved.Conclusion: The evaluation has informed the dialogue around the development of the country’s first national budgeted strategy that aims to accelerate the abandonment of all harmful traditionalpractices.
Evaluation development in Senegal
Authors: Lomeña-Gelis Monica
Published: October 2013

Background: This article outlined the diversified history, the current state and future prospects of planning and evaluation in Senegal. Objectives: The aim was to nurture debate on the quest for a more ‘African-rooted evaluation practice’. Method: The article was based on an extensive grey literature review, the author’s involvement in SenEval and personal interviews. The literature on development evaluation and evaluation capacity development helped to frame the overall analysis. Results: Donor policies and practices have heavily influenced evaluation practice in Senegal but recent changes are shifting the emphasis to more context-specific practice. Some encouraging signs are the creation of a high-level commission for evaluation, the impulsion of results-based management in public administrations and the improved monitoring of poverty reduction strategies. Also promising are the individual evaluation capacities of some local actors and more diversified, professionalised training. The last flagship activities promoted by SenEval, a voluntary organisation of professional evaluators, and the prospects of its formalisation, could be a turning point in the development of evaluation in Senegal. Nevertheless, evaluation practice remains today focused more on accountability and controlthan on learning. Moreover, the institutional setup is not coherent and consolidated to ensure a perennial system to manage, conduct and use evaluations, ensuring their quality and inclusion in the policy cycle. Conclusion: We argued that SenEval has a significant role to play in boosting demand, strengthening the policy and institutional framework and promoting exchanges with the African and international evaluation community.
Fear as dread of a God who kills and abuses? About a darker side of a key, but still forgotten biblical motif
Authors: De Villiers Pieter G.R.
Published: October 2013

This article investigates the motif of fear of God in biblical texts and contexts by discussing its use to indicate dread and by analysing the implications and consequences of such a reading of this key motif. After a brief overview of research on and contextual information about fear of God, it investigates fear as an intense and extreme human emotion and considers the reason why the motif is used by biblical authors in their discussions of the divine-human relationship, especially in the light of the fact that dread of God implies that God is a threatening force and dangerous power. It then evaluates how biblical authors embed fear within a configuration of thought that contains crucial themes of justice and holiness, without moving beyond this dimension of dread. Finally it investigates some hermeneutical considerations to cope with the challenges that an understanding of fear of God as dread brings with it.
A Pilot Curriculum to Integrate Community Health Into Internal Medicine Residency Training
Authors: Catalanotti Jillian , Popiel David , Johansson Patrik , Talib Zohray
Published: October 2013

Background

Public health training has become an important aspect of residency education. The Institute of Medicine recommends public health training for all resident physicians, and internal medicine educational milestones include general public health skills.

Objective

We sought to integrate community health into internal medicine residency training by developing a community health elective (CHE) curriculum.

Methods

We developed a 2-week CHE curriculum for internal medicine residents, featuring facilitated discussion sessions, clinical experience at health centers targeting medically underserved populations, and a culminating presentation. We evaluated our pilot curriculum using pre-elective and postelective course surveys with Likert-type questions.

Results

Of 150 eligible residents, 32 (21%) enrolled in the elective. Nearly all participants (30 of 32, 94%) strongly agreed that learning about community health was an important part of their residency training. Residents' perceived competence at discharging hospital patients with follow-up at community health sites increased 13-fold after taking the elective (P < .001). There was no increase in reported likelihood to practice in an underserved community or in primary care.

Conclusions

The CHE addresses several Accreditation Council for Graduate Medical Education competencies and internal medicine Milestones and could be a replicable model for internal medicine residency programs that seek to provide community health training.
The effects of β-glucan isolated from Pleurotus ostreatus on the development of arthritis and methotrexate treatment in rats with adjuvant arthritis
Authors: Rovenský Jozef , Stančíková Mária , Švík Karol , Bauerová Katarína , Jurčovičová Jana
Published: October 2013

Cel pracy: Celem badania była ocena wpływu β-(1,3/1,6)-D-glukanu izolowanego z grzyba Pleurotus ostreatus (β-glukan-PO) na postępowanie profilaktyczne oraz leczenie adiuwantowego zapalenia stawów (adjuvant arthritis – AA), a także na leczenie metotreksatem (MTX) u szczurów.

Materiał i metody: W grupie szczurów z AA profilaktycznie podawano MTX (1 mg/kg m.c. na tydzień), β-glukan-PO (1 mg/kg m.c. co drugi dzień) lub ich kombinację przez 28 dni od aplikacji adiuwantu. Metotreksat i β-glukan-PO (15 mg/kg m.c. codziennie) stosowano także terapeutycznie od 13. do 35. dnia po immunizacji. Jako markery stanu zapalnego oraz zapalenia stawów oceniano masę ciała, obrzęk tylnej łapy, wynik oceny artrogramu oraz stężenie albumin w surowicy.

Wyniki: Profilaktyczne podawanie małej dawki MTX znamiennie hamowało markery zarówno stanu zapalnego, jak i zapalenia stawów. Metotreksat i jego kombinacja z β-glukanem-PO znamiennie zwiększała masę ciała u szczurów z zapaleniem stawów. β-glukan-PO podawany w monoterapii nie wpływał na masę ciała, ale znamiennie zmniejszał zarówno obrzęk tylnej łapy, jak i wynik oceny zapalenia stawów. W skojarzeniu z MTX, β-glukan-PO znacznie wzmacniał korzystne działanie MTX, co powodowało wyraźniejsze zmniejszenie obrzęku tylnej łapy oraz obniżenie wskaźników oceny zapalenia stawów.

Stężenie albuminy w surowicy u szczurów w grupie kontrolnej z zapaleniem stawów było znamiennie mniejsze niż w grupie kontrolnej zdrowych osobników. Zarówno MTX w monoterapii, jak i leczenie skojarzone MTX + β-glukan-PO znamiennie hamowało zmniejszanie stężenia albuminy w surowicy. Pod względem terapeutycznym MTX nie wywierał istotnego wpływu na markery stanu zapalnego oraz zapalenia stawów. β-glukan-PO w dużej dawce (15 mg/kg m.c.) w monoterapii hamował obrzęk tylnej łapy, poprawiał wyniki oceny artrogramu oraz stężenie albuminy w surowicy.

Wnioski: β-glukan-PO w monoterapii działał korzystnie zarówno na rozwój, jak i leczenie AA stawów u szczurów oraz zwiększał skuteczność podstawowego leczenia za pomocą MTX. U pacjentów z reumatoidalnym zapaleniem stawów taki immunomodulator może zapobiegać wtórnym infekcjom i przywracać upośledzoną homeostazę immunologiczną.
Leczenie złamań kości krzyżowej za pomocą cementu kostnego u pacjentów z osteoporozą
Authors: Gasik Robert , Kubaszewski Łukasz , Mihułka Sławomir
Published: October 2013

Vertebral body fractures are most commonly observed fractures of the patients with osteoporosis. Most often are observed in the thoraco-lumbar junction and thoracic spine. It is rather seldom observed in the sacral bone. In case where sacral fracture was diagnosed in patient with osteoporosis, the available treatment procedures are similar to those used in the other vertebral compression fractures. Contemporary treatment protocol along with pharmacotherapy to slow down the bone turn-over, rehabilitation, orthotic treatment, advocates also for percutaneous injection with the bone cement of the sacral bone – sacroplasty.

Sacroplasty procedure gives chance to decrease the pain related to the fracture, limiting the immobilisation time, directly related to the bone density loss. The procedure can be performed in local anaesthesia with sedation, which is beneficial for elderly patients with co-morbidities. Contraindications for it are similar to those underlined in the rest of the spine: posterior wall fracture endangering the cement leakage to the spinal canal, neurological symptoms aggravated by the fracture occurrence, as well the general ones. In spite the sacroplasty is to be considered low risk procedures, serious complication might be observed. The most serious are cement leakage into the spinal canal or pulmonary or central nervous system embolisation with the cement. Sacroplasty, similarly to the vertebroplasty in the thoracic or lumbar spine might be a suitable procedure in osteoporotic fracture treatment of the sacrum.
Primary hemochromatosis with articular involvement
Authors: Kościńska-Ilczyszyn Kinga , Żuchowski Paweł , Wojciechowski Rafał , Jeka Sławomir
Published: October 2013

Hemochromatoza jest przewlekłą chorobą ogólnoustrojową wywołaną nadmiernym gromadzeniem żelaza. Wyróżnia się hemochromatozę pierwotną, uwarunkowaną genetycznie, oraz syderozy wtórne (wtórne zespoły nagromadzenia żelaza). Opis przypadku dotyczy 68-letniej pacjentki z dolegliwościami bólowymi stawów od kilku lat, z rozpoznaną hemochromatozą pierwotną, potwierdzoną badaniem genetycznym, z homozygotyczną mutacją genu HFE C282Y/C282Y, hospitalizowaną w klinice w Bydgoszczy z powodu podejrzenia reumatoidalnego zapalenia stawów (RZS). U chorej wykonano wiele badań diagnostycznych, m.in. badania radiologiczne, biochemiczne, ultrasonograficzne, jak również uwzględniono dane dotyczące wcześniejszych dolegliwości, schorzenia współistniejące oraz informacje z wywiadu rodzinnego, ustalając rozpoznanie hemochromatozy pierwotnej z zajęciem stawów. Opis tego przypadku wnosi istotne informacje przydatne w diagnostyce różnicowej RZS.
Usability issues in mobile learning: Students’ perceptions in Pakistani universities
Authors: Imtinan Umera , Chang Vanessa , Issa Tomayess
Published: October 2013

Usability in mobile devices, for learning, has drawn researchers’ attention since the term mobile learning has been coined in teaching and learning arenas. Current mobile devices in the market have ignored the design and styles for learning purposes. Although mobile devices have some features for games purposes, there are other important usability characteristics that ought to be considered to support learning. Therefore, mobile learning researchers need to investigate the learning options with the available capabilities of mobile devices. Students in developing countries reported more problems related to usability based on their individual experiences dealing with mobile devices for learning purposes. This paper aims to identify the implications of usability in mobile devices for learning based on research conducted in Pakistan.
Challenges against the successes of mLearn in Bangladesh
Authors: Parvin Shahanaj
Published: October 2013

Mobile learning is a recent phenomenon in the Bangladeshi education system. The ongoing English in Action project has been at the forefront of promoting the use of mobile technologies for English language training in Bangladesh, and has been one of the primary examples to demonstrate the potential of mobile devices in the classroom, and teacher professional support. This paper will discuss the challenges that have arisen in the promotion of mobile learning in Bangladesh, as well as the successes as highlighted by the English in Action project. Moreover, it will offer a brief glimpse into the work of the project and its mechanism for spreading mobile learning in typical Bangladeshi context.
Quality of sms-learning as a rapidly growing m-learning mode for foreign language learning
Authors: Fatahipour Majid , Najm Mahnaz Ghasemi
Published: October 2013

m-learning breaks away with the traditional education by focusing not just on developing mobile applications but also sms-learning (using regulated text messages) which is useful and engaging for learning English. Yet there is little research on the quality of sms-learning. In this paper, we view m-learning as an ever-present opportunity for learning in what Stead (2012) describes as today's blurred boundary between work and play. A service platform provider, the National Mobile Company of Iran, has enabled several private service providers (SPs) to use text messages for educational purposes. A contribution to the field is integrating theories of linguistics and m-learning. While learners benefit from extensive reading practice at their own pace (Day and Bamford, 1998), the four elements of m-learning proposed by Ray (2004) is a basis for measuring quality. The data comes from semi-structured interviews with three important SPs with 268 active subscribers to their English learning services. An survey was also conducted on the views of over 120 users on pros and cons of these services which found that although sms-learning is very engaging with informal tasks that impact learning (as theorized by Cross, 2007), it has to meet several challenges (e.g. meeting various requirements of learners and learning context, administrative hurdles/costs) to respond better to the users' expectations and learning needs. The quality is concluded as average because the services provided by the SPs were not strong in terms of personal sphere and context sensitivity although they were satisfactory in terms of efficiency and providing interaction.
Supporting Interaction in Learning Activities Using Mobile Devices in Higher Education
Authors: Shishah Wesam , Hopkins Gail , FitzGerald Elizabeth , Higgins Colin
Published: October 2013

Mobile devices are personal, portable and being increasingly used to assist students’ learning that creates new educational opportunities for students at university. Adopting mobile technologies to various educational activities that students are practicing in Higher Education (HE) is a key challenge yet one that could create powerful opportunities to support academic learning. This research will investigate how students at university use mobile devices with respect to engagement and interaction in various learning activities. It will study how students in HE engage with learning tasks and what social interactions occur when they are trying to achieve their academic goals. Also, the tools/software that support their academic goals in different learning settings or activities will be considered. This paper shows the background of the research to promote students’ interaction in various learning settings (including both different physical environments and different activities) using mobile learning support system.
Adjustment of cast metal post/cores modeled with different acrylic resins
Authors: Gusmão João Milton Rocha , Pereira Renato Piai , Alves Guilhermino Oliveira , Pithon Matheus Melo , Moreira David Costa
Published: October 2013

Aim: Evaluate the performance of four commercially available chemically-activated acrylic resins (CAARs) by measuring the level of displacement of the cores following casting. Materials and Methods: Two devices were constructed to model the cores based on a natural tooth. Forty post/cores were modeled, 10 in each of the following CAARs: Duralay (Reliance Dental, Illinois, USA), Pattern Resin (GC, Tokyo, Japan), Dencrilay (Dencril, Sao Paulo, Brazil), and Jet (Clássico, Sao Paulo, Brazil). Two casting rings were included,each of which contained 5 post/cores for each of the four CAARs tested, a total of 20 per ring. Following casting, the specimens were only sandblasted and separated from the feeding channels. The post/cores wereplaced in device 1 and, with the aid of an optical microscope, were attached to a digital camera. Images were then taken of the adjustment between the core and the remaining tooth on the labial surface. The images wereprocessed using the Image Tool for Windows, version 3.0, measuring three fixed points in each specimen. Data were statistically analyzed using the ANOVA and Tukey test. Results: The 40 post/cores were dividedinto eight groups according to resin brand and casting, obtaining the following results for mean and standard deviation (in mm): Dencrilay 0.192 CI (± 0.08), CII 0.058 (± 0.03); Duralay CI 0.097 (± 0.03), CII 0.131 (±0.06); Pattern CI 0.07 (± 0.03), CII 0.10 (± 0.05); and Jet CI 0.06 (± 0.02), CII 0.382 (± 0.17). Statistically significant differences could be identified when comparing the Dencrilay CI and the Jet CII with the remaining groups, which all proved to be unfavorable. Conclusion: The quality of cast metal post/core adjustment is not associated with the use of a specific acrylic resin.Uniterms: Post and core techinique. Acrylic resins.
Análise dos custos da saúde bucal na atenção básica no município de Vitória de Santo Antão, Pernambuco
Authors: Lorena Sobrinho José Eudes de , Espírito Santo Antônio Carlos Gomes do
Published: October 2013

Objetivo: Analisar os custos da saúde bucal na atenção básica no município da Vitória de Santo Antão, Pernambuco, no ano de 2010. Materiais e Métodos: Trata-se de um estudo de caso, onde foi utilizada ametodologia do custeio por absorção, sendo somados os custos com recursos humanos, com materiais odontológicos e de pensos com finalidade odontológica, com manutenção de equipamentos odontológicose os custos prediais das unidades de saúde. Calculou-se o percentual do financiamento por ente federativo (União, Estado e Município), o custo médio do procedimento odontológico e o custo médio da saúde bucal deatenção básica por habitante. Estabeleceu-se a representatividade do custo total sobre a despesa com a atenção básica e sobre a despesa total com saúde. Resultados: O custo total foi de R$ 1.340.307,80, sendo 85,6%(R$ 1.147.048,00) referentes aos recursos humanos, 8,5% (R$ 114.000,00) à manutenção de equipamentos, 3,2% (R$ 42.635,27) aos custos prediais e 2,7% (R$ 36.624,53) aos recursos materiais. Quanto às fontes de financiamento, 37,5% dos recursos foram provenientes da União e 62,5% do próprio Município. Não se observou repasse de recursos provenientes do Estado. O custo médio do procedimento foi de R$ 14,88 e ocusto médio da saúde bucal de atenção básica por habitante foi de R$ 17,61. O custo total representou 15,3% da despesa total com atenção básica e 6,7% da despesa total com a função saúde. Conclusão: os custos comrecursos humanos foram os mais representativos, sendo esta uma limitação para a ampliação da cobertura do serviço, diante da Lei de Responsabilidade Fiscal. O modelo de pacto federativo brasileiro continua conferindoao município a maior responsabilidade pelo financiamento das ações e serviços de saúde bucal, ainda que estes tenham baixa representatividade nos custos com a saúde.Descritores: Economia da saúde. Atenção primaria à saúde. Saúde bucal.
Discarded Bottles as a Mortality Threat to Shrews and Other Small Mammals in the Southern Appalachian Mountains
Authors: Brannon M. Patrick , Bargelt Lindsey B.
Published: October 2013

A total of 2,445 discarded bottles were inspected for skeletal remains at 50 roadside pull-off sites along the southeastern Blue Ridge escarpment of North Carolina and Georgia to assess their mortality risk to shrews. Of these, 1,196 bottles were open and served as potential traps, with an average of about 239 open bottles per km of roadside searched. Small mammal remains were found in bottles at 54.0% of the study sites and in 4.7% of the open bottles we examined. A total of 126 specimens were found in bottles representing 4 species of shrews, 2 species of rodents, and one mole, with approximately 25 entrapped specimens per km of roadside examined. Frequency of small mammal entrapment was 10.6% due in part to multiple captures in individual bottles, and the overall mortality rate was calculated as 32.3 animals per year across all sites. Although accumulation of new bottles in this region is slow, those that persist along roads generate enormous numbers of trap-nights which could potentially result in many small mammal fatalities.
The utility of a guideliner™ catheter in retrograde percutaneous coronary intervention of a chronic total occlusion with reverse cart—the “capture” technique
Authors: Mozid Abdul M. , Davies John R. , Spratt James C.
Published: October 2013

The hybrid approach to percutaneous treatment of chronic total occlusion (CTO) of coronary arteries requires both antegrade and retrograde skillsets. In the retrograde approach, wire externalization through the antegrade guide catheter often requires the use of a short donor guide catheter and a long (>150 cm) micro‐catheter. Despite this there are occasions where the micro‐catheter is unable to reach the anterograde guide catheter because of long collateral channels particularly when the retrograde limb involves a bypass graft. We report such a case where retrograde intervention was used to treat a right coronary artery (RCA) CTO in a patient with stable angina. The retrograde limb involved a saphenous vein graft to the native circumflex artery, which in turn provided collateral channels to the distal RCA. After performing reverse controlled anterograde and retrograde sub‐intimal tracking (CART), the retrograde micro‐catheter was only able to reach the mid RCA. To solve this, a Guideliner™ catheter was passed on the antegrade wire and successfully advanced over and “captured” the retrograde micro‐catheter. Wire externalization was then completed and the RCA was subsequently stented with a good final angiographic result. This case illustrates a novel approach to completing wire externalization and provides a further indication for the role of the Guideliner™ catheter in treating CTOs. © 2013 Wiley Periodicals, Inc.
Pulmonary complications in chronic liver disease
Authors: Machicao Victor I. , Balakrishnan Maya , Fallon Michael B.
Published: October 2013

The association of chronic liver disease with respiratory symptoms and hypoxia is well recognized. Over the last century, three pulmonary complications specific to chronic liver disease have been characterized: hepatopulmonary syndrome (HPS), portopulmonary hypertension (POPH), and hepatic hydrothorax (HH). The development of portal hypertension is fundamental in the pathogenesis of each of these disorders. HPS is the most common condition, found in 5%-30% of cirrhosis patients, manifested by abnormal oxygenation due to the development of intrapulmonary vascular dilatations. The presence of HPS increases mortality and impairs quality of life, but is reversible with liver transplantation (LT). POPH is characterized by development of pulmonary arterial hypertension in the setting of portal hypertension, and is present in 5%-10% of cirrhosis patients evaluated for LT. Screening for POPH in cirrhosis patients eligible for LT is critical since severe POPH is a relative contraindication for LT. Patients with moderate POPH, who respond adequately to medical therapy, may benefit from LT, although sufficient controlled data are lacking. HH is a transudative pleural effusion seen in 5%-10% of cirrhosis patients, in the absence of cardiopulmonary disease. Diagnosis of HH should prompt consideration for LT, which is the ultimate treatment for HH. Conservative management includes salt restriction and diuretics, with thoracentesis and transjugular intrahepatic portosystemic shunt (TIPS) as second-line therapeutic options. (HEPATOLOGY 2014;59:1627-1637)
Failure to Learn: A System View*
Authors: Holmes Sophia
Published: October 2013

Educational psychologists, remedial teachers and others working with children who are considered to have learning difficulties tend to regard the problem as being within the child and disregard the importance of the social/educational context. This paper argues that contextual factors are very important and classifies these factors in terms of the subsystems within the educational system. Typical subsystem structures and interactions are discussed and illustrated with case studies. The roles and interventions of the therapist working within the educational system are described. The numerous difficulties in working with a large system are discussed as well as some strategies for dealing with them.
Oxidation behavior of alloy HK40 in H2H2O atmosphere
Authors: Shao M.‐Z. , Cui L.‐S. , Zheng Y.‐J. , Wang Y.‐X. , Xing L.‐L.
Published: October 2013

In the present paper, the isothermal oxidation behavior of alloy HK40 in H2H2O atmosphere in the temperature range 850–950 °C was systematically investigated by means of TGA, XRD, SEM, and EDS. The results demonstrated that the oxidation of alloy HK40 under low oxygen partial pressure obeyed a cubic instead of parabolic rate law. The values of the oxidation rate constant k at 850, 900, and 950 °C were 0.0079, 0.01886 and 0.04031 mg3/(cm6 h) at 850, 900, and 950 °C, respectively. The scales were composed of MnCr2O4 and Cr2O3. MnCr2O4 mainly existed in the form of blades in the outer part of the scale and its amount gradually increased with increasing temperature. In addition, there were silica particles along the scale/metal interface and indications were found that they contribute to the improvement of scale spallation resistance at high temperature as found by scratch tests.
Corrosion dependence of an AlMgSi alloy under MgCl2 solution drop on initial concentration and humidity
Authors: Li J. F. , Zeng F. L.
Published: October 2013

The corrosion behavior of an Al–0.63Mg–0.28Si alloy under MgCl2 solution droplets with different initial concentration in environments of 33, 75, and 88% relative humidity (RH) was studied using a Kelvin probe. The available cathodic limiting current associated with oxygen reduction was highly dependent on the environment RH and initial concentration. In the 33% RH environment, metastable pitting was the main form of corrosion. In some cases at 75 and 88% RH, the potential baseline decreased slowly by hundreds of mV and remained at the lower value, indicating stable filiform‐like corrosion grew. The initiation time of the stable corrosion was determined by the environment RH and initial concentration. With increasing initial concentration or decreasing environment RH, the available cathodic limiting current decreased, stable corrosion was difficult to occur. The stable corrosion could occur outside the drop and/or inside the drop, which was dependent on not only the cathodic limiting current but also the environment RH.
Corrosion behavior of ZnNiAl2O3 nanocomposite coatings obtained by electrodeposition from alkaline electrolytes
Authors: Blejan D. , Muresan L. M.
Published: October 2013

The aim of this work was to investigate the anti‐corrosive properties of nanocomposite ZnNi coatings containing Al2O3 nanoparticles, prepared from alkaline commercial electrolytes (pH 13), (PERFORMA 280.5, COVENTYA S.A.S, France), by electrodeposition on carbon steel (OL37). The corrosion resistance of the coatings prepared with different concentrations of Al2O3 (5, 10, and 15 g/L) was evaluated in 0.2 g/L Na2SO4 solution (pH 5) by open circuit potential (OCP) measurements, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) techniques. The results of electrochemical measurements were corroborated with those obtained by using X‐ray diffraction analysis. The obtained results show that the introduction of Al2O3 nanoparticles in the plating bath generally brings an increase in corrosion resistance of ZnNi layers and put in evidence the existence of an optimal Al2O3 concentration. Under the examined conditions, the optimal concentration determined from polarization measurements was proven to be 5 g/L Al2O3. The highest value of the polarization resistance, Rp, obtained from impedance measurements corresponds also to ZnNi with 5 g/L Al2O3, which is in agreement with the results obtained from polarization and XRD measurements.
Optimization of corrosion process of stainless steel coating during cleaning in steel brewery tanks
Authors: Rezić T. , Rezić I. , Blaženović I. , Šantek B.
Published: October 2013

The aim of this research was to optimize and investigate effects of corrosion process during cleaning of stainless‐steel coatings in microbrewery tanks and to predict their resistance to nitric acid in washing solution. Experimental conditions were limited with minimal concentration of acid that satisfied requirements of sanitation protocol, and maximal concentration of acid that did not cause corrosion and release of metals higher then prescribed law limits. Process was monitored by release of metal ions and optimized by design of experiment (DOE) using software Design‐Expert. This approach proved to be very beneficial, cost reductive, and effective for optimization of complex systems. The results of experiments prediction were compared to additional testing, and their matching proved the effectiveness of modeling. Therefore DOE is an effective tool for estimation of steel coating corrosion processes. In addition, optimized values satisfied required criteria, so the proposed protocol can be used in the effective sanitation of industrial tanks and pipelines in brewing industry.
Corrosion protection of pure aluminium and aluminium alloy (AA7075) in salt solution with silane‐based sol–gel coatings
Authors: Younis A. A. , Ensinger W. , El‐Sabbah M. M. B. , Holze R.
Published: October 2013

Sol–gel films of tetraethoxysilane (TEOS), phenyltriethoxysilane (PTES) and phenyltrimethoxysilane (PTMS) were prepared on aluminium and aluminium alloy AA7075 and characterised. The corrosion inhibition properties of uncoated and coated specimens were evaluated with potentiodynamic polarisation scan, linear polarisation resistance and open circuit potential measurements. With scanning electron microscopy and optical microscopy effects of the sol–gel coating were shown. Weight loss measurements were performed at different pH‐values. More hydrophobic coatings as PTMS show a considerably better corrosion inhibition capacity as compared to the capacity provided by less hydrophobic ones as TEOS and PTES.
The effect of atmospheric pollution on materials damage
Authors: Syed S.
Published: October 2013

According to ASTM G50‐76, materials have been exposed to atmospheres of Saudi Arabia. Environmental factors such as temperature, relative humidity and deposition rates of pollutants (Cl− and SO2) were investigated. X‐ray diffraction was used for characterization. Corrosion rates were determined by weight loss. As per ISO 9223, aggressivity classification was made. The results obeyed well with the empirical kinetics equation of the form C = Ktn, where K and C are the corrosion losses in mg/cm2 after 1 and t years of the exposure, respectively, and n is constant. Based on n values, the corrosion mechanisms of samples are predicted.
Corrosion rate and corrosion product characterisation using Raman spectroscopy for steel embedded in chloride polluted fly ash mortar
Authors: Criado M. , Martínez‐Ramirez S. , Fajardo S. , Gómez P. P. , Bastidas J. M.
Published: October 2013

Electrochemical impedance spectroscopy (EIS) and polarisation curves assisted by Raman spectroscopy were used to study the corrosion behaviour and to characterise the corrosion products of reinforcing steel embedded in fly ash mortars with and without chloride pollution. Two alkaline solutions with different soluble silica contents were utilised to activate the fly ash. After 720 days of experimentation the reinforcing steel embedded in fly ash mortar without chlorides remained passive, while the specimens in fly ash polluted with chloride ions (0.4 and 2%) yielded current density values of the order of 2 × 10−5 A/cm2, typical of an active state. The main corrosion products identified on the steel surface were less crystallised phases of iron oxyhydroxide hydrates and goethite (α‐FeOOH) or lepidocrocite (γ‐FeOOH).
Instrumented impact test of duplex stainless steel miniature specimen
Authors: Wunder J. , Karl A. , Dwars A. , Böhm A.
Published: October 2013

The paper describes a new approach to characterize metallic materials by a novel instrumented notch impact test for samples with small specimen size. A piezo‐electric sensor mounted on the pendulum hammer provides force information during the fracture process. By numerical integration of the signal the absorbed impact energy can be calculated very exactly. Further information about the fracture behavior can be extracted from the resulting force‐displacement‐diagram. Several duplex stainless steels in different heat treatment conditions were tested and compared to standard Charpy impact testing specimen. It is concluded that different grades of embrittlement of duplex materials can be detected with high accuracy. Due to a data acquisition rate of 250 kilo‐samples/second and limited stiffness of the pendulum hammer impact energies of less than 7% of maximum energy materials with high brittleness can only be characterized qualitatively.
Directional dependence of the fatigue crack growth rate on Ti‐6Al‐4V due to a microstructural related transition of the crack closure mode
Authors: Kriegsmann A. , Müller C.
Published: October 2013

An der (α+β)‐Titanlegierung Ti‐6Al‐4V wurde durch gezielte Wärmebehandlung in einem Temperaturgradienten ein scharfer Gefügeübergang von globularem zu lamellarem Gefüge eingestellt. Globulare Gefüge zeigen bereits bei geringen Belastungen rein plastizitätsinduzierte Rissschließung, während bei lamellaren Gefügen bis zu hohen ΔK Werten rauigkeitsinduzierte Rissschließung beobachtet wird. Der gezielt eingestellte Gefügeübergang ermöglicht es somit, die Auswirkung eines Wechsels im Rissschließmodus (rauigkeitsinduziert, plastizitätsinduziert) auf die Rissausbreitung bei einer konstanten Schwingbreite der Spannungsintensität ΔK zu untersuchen. Beim Wechsel der Rissschließung von plastizitätsinduzierter zu rauigkeitsinduzierter Rissschließung stellt sich die Rissöffnungsbelastung für das jeweils an der Rissspitze vorliegende Gefüge ein. Beim Wechsel von rauigkeitsinduzierter zu plastizitätsinduzierter Rissschließung hingegen treten signifikante Rissschließeffekte im Risspfad auf, die zu höheren Rissöffnungsbelastungen und damit zu einer Verringerung der Rissausbreitungsgeschwindigkeit beitragen. Hierdurch entsteht für eine konstante Belastung ΔK eine Richtungsabhängigkeit der Rissausbreitungsgeschwindigkeit.
Cavitation tests to materials and coatings – comparison of different evaluation processes and identification of the cavitation erosion of EN‐GJS‐600‐3, G‐CuAl8Mn8 and GX4CrNi13‐4 + QT
Authors: Gäkle M. , Kley M. , Ritzel L.
Published: October 2013

Werkstoffschäden an kavitationsbelasteten Strömungsmaschinen verursachen Kosten durch Reparatur und Stillstandszeit der Maschinen. Ziel muss es daher sein, die Kavitation durch Strömungsoptimierung zu verringern und durch eine geeignete Werkstoffauswahl in einen zeitlich unkritischen Bereich zu verschieben. Daher ist es erforderlich die Kavitationsbeständigkeit von Werkstoffen und Beschichtungen, welche zur Steigerung der Lebensdauer eingesetzt werden können, zu untersuchen. Im Hinblick auf eine umfassende Versuchsreihe wurde die Eignung verschiedener Auswerteverfahren wie Tastschnittmessung, Weißlichtprofilometrie, Wägung und optischer Vergleich untersucht um für den jeweiligen Anwendungsfall eine geeignete Auswertemethode auswählen zu können. Die Ergebnisse zeigen, dass sich zur Auswertung von Werkstoffversuchen die Wägung mit einer hochauflösenden Waage am besten eignet, wobei die Weißlichtprofilometrie dieser bei der genauen Auswertung von Beschichtungsversuchen deutlich überlegen ist. Der optische Vergleich eignet sich in beiden Fällen um schnelle Vergleiche anzustellen. Beispielhafte Untersuchungen zeigen die Kavitationsresistenz von G‐CuAl8Mn8 gegenüber den untersuchten Stählen auf.
Investigation on a new process chain of deposition or friction welding and subsequent hot forging
Authors: Frischkorn C. , Huskic A. , Hermsdorf J. , Barroi A. , Kaierle S. , Behrens B.‐A. , Overmeyer L.
Published: October 2013

According to the state of the art most current forging parts and technical components are made of mono‐materials. Nevertheless, parts consisting of only one material increasingly reach their specific material and constructive limits in the established production processes. Through use of previously joined raw parts consisting of different materials, it is possible to produce application‐optimized hybrid parts. This paper describes the production chain of hybrid parts produced by combining two different joining processes with subsequent hot compression tests. The joining of various materials is realized by a deposition welding with a laser‐stabilized gas‐metal‐arc deposition welding (LGD) process and a conventional friction welding process. Subsequently, the hybrid samples are compressed under varying forming parameters such as temperature and deformation degrees. In order to characterize the joining zone, metallurgical investigations are carried out.
Investigation of jarosite process tailing waste by means of raman and infrared spectroscopy
Authors: Kerolli‐Mustafa M. , Bačić I. , Ćurković L.
Published: October 2013

The aim of this work was to identify and characterize three samples of jarosite process tailing waste in Mitrovica, Kosovo, using Raman and Fourier transform infrared (FTIR) spectroscopy. The identification is made based on the assignment of bands in the Raman and FTIR spectra. Both Raman and FTIR spectra show the fundamental stretching and bending vibration mode of SO42–, OH– and NH4+ groups. The results obtained by the means of Raman and infrared spectroscopy are compared with cited reference data in order to sum the analysis of vibrational spectra.
Managing External Risks for International Architectural, Engineering, and Construction (AEC) Firms Operating in Gulf Cooperation Council (GCC) States
Authors: Loo Siaw Chuing , Abdul-Rahman Hamzah , Wang Chen
Published: October 2013

International projects involve both uncertainties raised domestically and external risks in international transactions. Through a questionnaire survey and case studies among architectural, engineering, and construction (AEC) firms operating in the Gulf, this study found 36.5% external risk factors that should be contemplated before the award of contracts and 53.9% afterward to ensure smooth running. An external risk breakdown structure (E-RBS) and a framework for foreign AEC firms operating in Gulf Cooperation Council (GCC) states were developed for users to identify and respond to external risks in a more systematic manner. International firms outside Malaysia are strongly advised to use the framework for risk forecasting and mitigation when operating in the Gulf.
Fragmentations of [M–H]– anions of peptides containing Ser sulfate. A joint experimental and theoretical study
Authors: Nha Tran T. T. , Wang Tianfang , Hack Sandra , Bowie John H.
Published: October 2013

RATIONALE

To determine the negative‐ion cleavages from [M–H]– ions of Ser sulfate‐containing peptides using experiment and theory in concert.

METHODS

Fragmentations were explored using a Waters QTOF2 mass spectrometer in negative‐ion electrospray mode, together with calculations at the CAM‐B3LYP/6‐311++g(d,p) level of theory. Peptides used in this study were:
urn:x-wiley:09514198:media:rcm6686:rcm6686-math-0001

RESULTS

Previously, it has been shown that a peptide containing a Tyr sulfate group shows [(M–H)––SO3] as the base peak. Only a small peak was observed corresponding to HOSO3– (formed following rearrangement of the sulfate). A Ser sulfate‐containing peptide, in contrast, shows pronounced peaks due to cleavage product anions [(M–H)––SO3] and HOSO3–. Theoretical calculations at the CAM‐B3LYP/6‐311++g(d,p) level of theory suggest that rearrangement of a Ser sulfate to give C‐terminal CO2SO3H is energetically unfavourable in comparison with fragmentation of the intact Ser sulfate to yield [(M–H)––SO3] and HOSO3–. [(M–H)––H2SO4] anions are not observed in the spectra of peptides containing Ser sulfate, presumably because HOSO3– is a relatively weak gas‐phase base (ΔGacid = 1265 kJ mol–1).

CONCLUSIONS

Experimental and theoretical data suggest that [(M–H)––SO3] and HOSO3– product anions (from a peptide with a C‐terminal Ser sulfate) are formed from the serine sulfate anion accompanied by specific proton transfer. CID MS/MS/MS data for an [(M–H)––SO3] ion of an underivatised sulfate‐containing peptide will normally allow the determination of the amino acid sequence of that peptide. The one case we have studied where that is not the case is GLS(SO3H)GDA(OH), where the peptide contains Ser sulfate and Asp, where the diagnostic Asp cleavages are competitive with the Ser sulfate cleavages. Copyright © 2013 John Wiley & Sons, Ltd.
The quantitative surface analysis of an antioxidant additive in a lubricant oil matrix by desorption electrospray ionization mass spectrometry
Authors: Da Costa Caitlyn , Reynolds James C. , Whitmarsh Samuel , Lynch Tom , Creaser Colin S.
Published: October 2013

RATIONALE

Chemical additives are incorporated into commercial lubricant oils to modify the physical and chemical properties of the lubricant. The quantitative analysis of additives in oil‐based lubricants deposited on a surface without extraction of the sample from the surface presents a challenge. The potential of desorption electrospray ionization mass spectrometry (DESI‐MS) for the quantitative surface analysis of an oil additive in a complex oil lubricant matrix without sample extraction has been evaluated.

METHODS

The quantitative surface analysis of the antioxidant additive octyl (4‐hydroxy‐3,5‐di‐tert‐butylphenyl)propionate in an oil lubricant matrix was carried out by DESI‐MS in the presence of 2‐(pentyloxy)ethyl 3‐(3,5‐di‐tert‐butyl‐4‐hydroxyphenyl)propionate as an internal standard. A quadrupole/time‐of‐flight mass spectrometer fitted with an in‐house modified ion source enabling non‐proximal DESI‐MS was used for the analyses.

RESULTS

An eight‐point calibration curve ranging from 1 to 80 µg/spot of octyl (4‐hydroxy‐3,5‐di‐tert‐butylphenyl)propionate in an oil lubricant matrix and in the presence of the internal standard was used to determine the quantitative response of the DESI‐MS method. The sensitivity and repeatability of the technique were assessed by conducting replicate analyses at each concentration. The limit of detection was determined to be 11 ng/mm2 additive on spot with relative standard deviations in the range 3–14%.

CONCLUSIONS

The application of DESI‐MS to the direct, quantitative surface analysis of a commercial lubricant additive in a native oil lubricant matrix is demonstrated. © 2013 The Authors. Rapid Communications in Mass Spectrometry published by John Wiley & Sons, Ltd.
An integrated exact mass spectrometric strategy for comprehensive and rapid characterization of phenolic compounds in licorice
Authors: Xu Tongtong , Yang Min , Li Yifeng , Chen Xin , Wang Qiurong , Deng Wangping , Pang Xiayan , Yu Kate , Jiang Baohong , Guan Shuhong , Guo De‐an
Published: October 2013

RATIONALE

Licorice (Gancao) is derived from the dried roots and rhizomes of Glycyrrhiza species (Leguminosae) and appears as a component herb in about 60% of traditional Chinese medicine (TCM) prescriptions. Modern pharmacological studies have shown that flavonoids are one class of the major components responsible for the bioactivities of licorice. Ultra‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry (UPLC/QTOF MS) has proven to be a powerful tool for rapid profiling and identification of natural products in complex herbal medicines.

METHODS

A UPLC/QTOF MS method was established for the first time for profiling and structural characterization of the phenolic compounds (most of them flavonoids) in licorice. The combined use of data‐independent acquisition (MSE) and data‐dependent acquisition (DDA) was illustrated.

RESULTS

Fifteen flavonoid reference compounds were used to explore the fragmentation pathways. Compound identification was based upon the exact mass, general fragmentation behaviors, retention times, UV absorption, and the related botanical biogenesis. As a result, a total of 51 compounds were characterized, three of which were reported for the first time.

CONCLUSIONS

The LC/MS analysis for each injection took less than 9 min. The developed method is fast, accurate and reliable due to its high resolution and high efficiency characteristics as a result of combining both UPLC separation and QTOF exact mass measurement. Copyright © 2013 John Wiley & Sons, Ltd.