bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the Formability of Aluminium Alloy Sheets at Room and Elevated Temperatures
Authors: Zhou Jia , Zhang Jun Ping , Ma Ming Tu
Published: November 2016

This paper presents the main achievements of a research project aimed at investigating the applicability of the hot stamping technology to non heat treatable aluminium alloys of the 5052 H32 and heat treatable aluminium alloys of the 6016 T4P after six months natural aging. The formability and mechanical properties of 5052 H32 and 6016 T4P aluminum alloy sheets after six months natural aging under different temperature conditions were studied, the processing characteristics and potential of the two aluminium alloy at room and elevated temperature were investigated. The results indicated that the 6016 aluminum alloy sheet exhibit better mechanical properties at room temperature. 5052 H32 aluminum alloy sheet shows better formability at elevated temperature, and it has higher potential to increase formability by raising the temperature.
Effect of Dispersoids on Long-Term Stable Electrical Aluminium Connections
Authors: Kemsies Richard H. , Milkereit Benjamin , Kessler Olaf , Fuhrmann Torsten , Schlegel Stephan , Plonus Falk , Miller-Jupp Simon Peter , Hirsch Jürgen
Published: November 2016

In electrical power systems bolted joints with bus bars made of aluminium are common, whereby the tendency towards higher operating temperatures can be observed. At higher temperatures a reduction of the joint force can occur due to creep and/or stress relaxation processes, which leads to an increasing electrical resistance and, in the worst case, to failed joints. The aim of this project is to increase the creep resistance (and to minimise the stress relaxation) of aluminium conductors for electrical applications without a significant reduction in their electrical conductivity – even after long-term exposure to elevated temperatures. The effect of dispersoids in different aluminium alloys on the longterm behaviour of currentcarrying joints at high temperatures (i.e. 140 °C) was investigated. Longterm tests on bolted joints with force measuring devices were performed to monitor the joint forces and to measure the joint resistances, both with and without current supply.
Effect of Microstructure on Impact Energy of an Al-Mg-Sc Alloy
Authors: Zhemchuzhnikova Daria , Kaibyshev Rustam
Published: November 2016

Analysis of the absorbed impact energy of an Al-Mg-Sc alloy after different thermo-mechanical processing routes was investigated between-196°C and 20°C. The material with a grain size of ∼ 22 μm in cast condition and with an average grain size of 0.7 μm produced by was produced by equal-channel angular pressing (ECAP) exhibits well-defined ductile-brittle transition in the temperature interval-60...-100°C, however, even at-196°C the value impact energy of fine-grained alloy is higher by a factor of 2 in comparison with coarse-grained state. The impact toughness of the hot rolled alloy linearly decreases with decreasing temperature. The influence of different microstructures on impact toughness and fracture behavior of alloy is discussed.
Quantification of Fatigue Weaklinks in High Strength Al Alloys
Authors: Yang Lin , Jin Yan , Cai Pei , Yin Fu Xing , Li Qiang , Zhai T.
Published: November 2016

Fatigue weak-link density and strength distribution are materials fatigue properties which are useful in evaluation of alloy quality in terms of the fatigue crack nucleation behavior. This paper reports: 1) an experimental methodology developed to measure fatigue weak-link density and strength distribution by measuring surface crack population as a function of the maximum applied stress, and 2) a quantitative model to quantify fatigue weak-links, based on the 3-D effects of pores in cast alloys. The experimental method could be employed to characterize the fatigue crack initiation behaviors and their anisotropy in wrought and cast Al alloys such as AA8090 Al-Li, AA2026, AA7075 and A713 alloys. It was found that the crack populations were a Weibull function of the applied maximum stress. By fitting this measured curve, fatigue weak-link density could be quantified in these alloys. The derivative of the measured Weibull function resulted in the strength distribution of the fatigue weak-links. The fatigue weak-links could also be quantified from the reconstructed microstructure of a cast Al alloy by analyzing the stress/strain fields around a micro-pore (an elasto-plastic media) under cyclic loading as a function of pore position in depth on surface using a 3-D finite element method. The incubation life for the fatigue crack initiated from a surface pore could be estimated using a microscopic scale Manson-Coffin equation. The results obtained using the 3-D pore-sensitive model were consistent with the experimental results, i.e., the crack population was a Weibull function of the applied stress. The percentage of crack initiation life was found to increase with decrease in cyclic load, i.e., at the stress just above the fatigue limit, it was over 95% the total fatigue life, compared to just 62.5% at the maximum stress of 110% yield strength.
Effects of Sn Addition on Clustering and Age-Hardening Behavior in a Pre-Aged Al-Mg-Si Alloy
Authors: Shishido Hisao , Takaki Yasuo , Kozuka Masaya , Matsumoto Katsushi , Aruga Yasuhiro
Published: November 2016

The effects of Sn addition on clustering and age-hardening behavior in an Al-0.6Mg-1.0Si (mass %) alloy were investigated. Addition of Sn delayed the age-hardening in single aging at 170 ̊C. On the other hand, Sn promoted the age-hardening response in 3-step aging process which comprises a pre-aging (PA) at 90 ̊C for 18ks followed by natural aging (NA) for 604.8ks and artificial aging (AA) at 170 ̊C. The characteristics of clusters formed during PA and NA were evaluated by differential scanning calorimetry (DSC) analysis and atom probe tomography (APT). The DSC results show that the endothermic peak at around 160 ̊C to 200 ̊C was observed in the Sn-free alloy. On the other hand, in the Sn-added alloy, endothermic peak was not observed. It is suggested that Sn addition suppresses the formation of the clusters formed during NA. The APT results show that the Sn addition decreases the number density of clusters, especially smaller clusters. No Sn precipitates were found in Mg-Si precipitates formed during AA at 170 ̊C for 3.6ks. It is speculated that suppression of smaller cluster formation by addition of Sn promotes the age-hardening response
Preliminary Investigation into the Suitability of 2xxx Alloys for Wire-Arc Additive Manufacturing
Authors: Fixter J. , Gu J. , Ding J. , Williams Stewart W. , Prangnell Philip B.
Published: November 2016

An investigation has been performed into the compatibility of aluminum alloys used in the aerospace industry with Wire-Arc Additive Manufacturing. Modelling and preliminary experimental trials have been performed to show that it is viable to use Al-Cu-Mg alloys, like 2024, without solidification cracking. A relatively fine and texture free grain structure was obtained in the as-deposited WAAM material and the addition of inter-pass deformation, by rolling each added layer, led to further grain size refinement. With adequate control of porosity and subsequent heat treatment, the WAAM material was found to have tensile properties comparable to that of standard wrought products.
Microstructural and Mechanical Characteristics of Cladding Billets with Different Clad Ratios
Authors: Han Xing , Cui Jian Zhong
Published: November 2016

AA4045/AA3003 cladding billets with different clad ratios were fabricated by direct chill casting process. The macrostructures, microstructures, compositions distribution and the mechanical properties near the bonding interface were investigated in detail. The results show that the cladding billet with few defects could be obtained by semi-continuous casting process. The metallurgical bonding was formed due to the diffusions of elements. The decreasing of clad ratio changed the microstructure at the interface and reduced the thickness of diffusion layer. The hardness around the interface is higher than that of AA3003 side but lower than that of the other side, indicating that the interface yield strength is also higher than that of AA3003. After extrusion process, the characteristics of the interface remain that of as-cast cladding billet.
Adsorptive CuO/CuAl2O4 Nanoparticles for the Separation of Aqueous Methyl Orange
Authors: Menon Samvit G. , Choudhari K.S. , Kulkarni Suresh D. , Santhosh C.
Published: November 2016

A simple method for the separation of aqueous methyl orange, an azo dye, is reported, where CuO/CuAl2O4 nanoparticles synthesisedby co-precipitation methodwere used as the adsorbent. The presence of cubic CuAl2O4 (CAO) and monoclinic CuO phase of this composite material was confirmed by X-Ray diffraction and its specific surface area wasdetermined by BET nitrogen adsorption method.To study the nature of surface charge, theisoelectric point of the material was determined using the pH drift methodfollowing which the rate of decolouration was studied forpH 5and pH 7. Theexperiments in the absence oflight show that adsorption of the dye is prevalent even up to 6h leading to 86% decolouration.A methanolic extraction was effectivefor quantitative separation ofadsorbed dye fromCuO/CuAl2O4 nanoparticles regenerating them for reuse. The presence of methyl orange in the extracted solution and on the nanoparticles at various stages was verified byUV-Visible and FT-IR spectroscopic methods.The extent of adsorption was quantified and found tobe as high as 86%. The catalyst aftercomplete extraction ofmethyl orange (MO),could be reused for the decolouration. Stability of the nanoparticles after reuse was verified by the closematch of XRD patterns ofthe pure and reused CAOwhich show no significant changes in itscrystal structure. The separation method shown here can be extended for the removal of other azo dyesfrom textile effluents.
Studies on Control of Erratic Release of Ketoprofen from Commercial Patches for Sustained Pain-Relief Using Silica Microparticles
Authors: Gaware S. , Bala Preetam , Dhobale Sandip , Joshi Anand , Wagh Narendra , Pal Kavita , Kale Sangeeta N.
Published: November 2016

Sustained release of pharmaceutical drug has been a challenge to medical practitioners for a very long time. This is a requirement of anaesthetists, endoscopic surgeons and even dentists. Though commercial bandages are already available for pain and inflammation control, their drug release mechanism is mostly unknown, and is predominantly erratic. This poses a dilemma for medical practitioners, due to which, even if it is recommended to keep patch adhered to skin for 6 hours, it is often replaced in couple of hours or many a times a good amount of undelivered drug remains in the patch and gets wasted. Combining this need for systematic release of drug through such commercial patches and the property of sustained release of drug molecules through mesoporous silica particles, led to an idea for using a coat of Silica Microparticles (SiMPs) on to these patches to achieve controlled and sustained release of drug, mainly Ketoprofen (KP) (a pain-relieving commercial drug). SiMPs were synthesised and coated with pure KP drug on one hand and on another a thin layer of SiMPs was coated on the commercial KP patch. The sustained release studies were done for duration of 6-8 hours. The structural chemistry and the interaction chemistry of the silica-trapped-KP showed that the carboxylic acidic group of hydrogen from KP makes partial bond with silica through weak van-der-Waal forces interaction and efficiency of 75 % of drug loading. The commercial KP patch showed initial burst and later erratic release. However, KP patches upon coating with SiMPs showed controlled release of drug, with the initial burst release and subsequent sustained release in the agar platform-based drug release study. Loose conjugational chemistry, with good bio-availability of SiMPs provides a fine control over the release mechanism, which probably forms a fine mesh-matrix through which the drug slowly percolates. Further, since the particles are not too small, the passage of these particles through the skin-barrier is also less-probable, thereby imparting a facilitative effect for drug passage, in a controlled fashion. Hence a simple strategy is proposed to achieve better medicinal patches for pain-control and better drug efficacy.
An Experimental and Simulation Studies on Sound Absorption Coefficients of Banana Fibers and their Reinforced Composites
Authors: bin Bakri Muhammad Khusairy , Jayamani Elammaran , Heng Soon Kok , Hamdan Sinin , Kakar Akshay
Published: November 2016

This research focuses on the simulation of sound absorption coefficient of banana fiber and experimentation of sound absorption coefficient of banana fiber epoxy composites. For simulation, ‘Mechel’ empirical model was used to manipulate the flow resistivity and ‘Delany and Bazley’ empirical model was used to develop the prediction of sound absorption coefficient at frequency ranges from 500 Hz to 6000 Hz. For experimentation, two-microphone transfer function impedance tube model was used to analyze the sound absorption coefficient at frequency ranges from 500 Hz to 6000 Hz. Based on simulation, it is predicted and analyzed that the sound absorption coefficient of banana fiber found to be as high as 0.97 for the effects on the material thickness of banana fiber and 0.64 for the effects on the fiber diameter size and flow resistivity of banana fiber in the frequency ranges from 500 Hz to 6000 Hz. According to experimental results, it is observed and analyzed that the sound absorption coefficient of banana epoxy composites found to be as high as 0.11 for untreated banana epoxy composites and 0.12 for treated banana epoxy composites in the frequency ranges from 500 Hz to 6000 Hz.
Detection of Posttraumatic Stress Symptoms in Patients After Discharge From Intensive Care
Authors: Warlan Heather , Howland Lois , Connelly Cynthia
Published: November 2016

Background

Despite emphasis on identifying personal and clinical characteristics that place patients at higher risk for posttraumatic stress syndrome after intensive care, the extent of screening for the syndrome in intensive care patients is unknown.

Objectives

To examine the feasibility and acceptability of a screening tool to detect posttraumatic stress syndrome, screen for the syndrome soon after discharge from intensive care to identify patients at risk for post-traumatic stress disorder, and determine personal and clinical factors related to higher scores on the screening instrument.

Methods

A single-center, cross-sectional design was used. At 2 to 4 weeks after hospital discharge, 41 patients treated in an intensive care unit completed the screening instrument and the Screening Experience Questionnaire via telephone. Associations between participants’ characteristics and scores were examined, and screening experiences were described.

Results

Participants reported that the screening instrument was easy to understand, caused little distress, and could be completed in an acceptable time frame. Participants reported that they had not been screened via a formal process or received education during or after their stay in the unit. Among the participants, 44% preferred screening in the outpatient setting. Higher scores on the screening tool were associated with history of depression, moderate levels of sedation, and intensive care unit delirium.

Conclusions

The majority of intensive care patients most likely are not being screened for posttraumatic stress syndrome despite a higher risk for the syndrome in these patients than in the general population.
Limitation in the use of spectral analysis to detect Weligama coconut leaf wilt disease affected palms in Southern Sri Lanka
Authors: Nainanayake A. D. , Gunathilake J. , Kumarathunga M. D. P. , Gunawardena P. M. , Wijesekara H. T. R.
Published: November 2016

Weligama Coconut Leaf Wilt Disease (WCLWD) was first reported in late 2006 in the Weligama Divisional Secretariat Division (DSD) in Matara District in the Southern Province of Sri Lanka. Surveys conducted in 2012 revealed that 65,838, 251,980 and 14,344 palms affected by the disease in Galle, Malara and Hambanlota districts respectively. It has been confirmed by the Coconut Research Institute that the disease is caused by a phytoplasma which has some resemblance to the phytoplasma of Coconut Root (Wilt) disease in India. A 3 km wide boundary was demarcated covering the area affected by the disease and all suspicious palms were removed in the boundary zone. In the core area, affected palms were gradual removed. The disease prevailing area spanned > 680 km2 and the detection of affected coconut palms across such a large area became practically difficult. Therefore, the objective of the present study was to find alternative methods to detect affected coconut palms with yellowing leaves prominent at the middle stage of the disease, using multispectral satellite images of 0.5 m resolution. It was envisaged to use this technique as a supportive management tool at field level, if successful. Normalized Differential Vegetation Index (NDVI) which is the standard and widely used algorithm for detecting vegetation under stress conditions did not reveal an appreciable isolation of canopies of affected coconut palms. Of the different customized algorithms tested, the best outcome was obtained by the algorithm (Red + Green) - 2 x (Blue). When this algorithm was applied to the multispectral satellite images of 0.5 m resolution in the affected area, adult coconut palms in advanced stage of the disease could be distinguished with an accuracy of above 80%. However, a detection of palms in the early stages of the disease where leaf flaccidity is the major morphological symptom could not be made with an acceptable level of accuracy. Moreover, the detection of affected coconut seedlings was much more difficult. Thus, only an overall accuracy of 60 - 70% could be achieved by this approach with multispectral satellite images of 0.5 m resolution. Although the level of accuracy is not sufficient for a comprehensive field level application, there is scope for further improvement using images with higher resolution.
IL-27 Is Essential for Suppression of Experimental Allergic Asthma by the TLR7/8 Agonist R848 (Resiquimod)
Authors: Jirmo Adan Chari , Daluege Kathleen , Happle Christine , Albrecht Melanie , Dittrich Anna-Maria , Busse Mandy , Habener Anika , Skuljec Jelena , Hansen Gesine
Published: November 2016

Different models of experimental allergic asthma have shown that the TLR7/8 agonist resiquimod (R848) is a potential inhibitor of type 2 helper cell–driven inflammatory responses. However, the mechanisms mediating its therapeutic effects are not fully understood. Using a model of experimental allergic asthma, we show that induction of IL-27 by R848 is critical for the observed ameliorative effects. R848 significantly inhibited all hallmarks of experimental allergic asthma, including airway hyperreactivity, eosinophilic airway inflammation, mucus hypersecretion, and Ag-specific Ig production. Whereas R848 significantly reduced IL-5, IL-13, and IL-17, it induced IFN-γ and IL-27. Neutralization of IL-27 completely reversed the therapeutic effect of R848 in the experimental asthma model, demonstrating dependence of R848-mediated suppression on IL-27. In vitro, R848 induced production of IL-27 by murine alveolar macrophages and dendritic cells and enhanced expression of programmed death–ligand 1, whose expression on monocytes and dendritic cells has been shown to regulate peripheral tolerance in both murine and human studies. Moreover, in vitro IL-27 enhanced secretion of IFN-γ whereas it inhibited IL-5 and IL-13, demonstrating its direct effect on attenuating Th2 responses. Taken together, our study proves that R848-mediated suppression of experimental asthma is dependent on IL-27. These data provide evidence of a central role of IL-27 for the control of Th2-mediated allergic diseases.
Development, Functioning, and Effectiveness of a Preoperative Risk Assessment Clinic
Authors: Tariq Hassan , Ahmed Rafeeq , Kulkarni Salil , Hanif Sana , Toolsie Omesh , Abbas Hafsa , Chilimuri Sridhar
Published: October 2016

Lee first described the concept of preoperative assessment testing (PAT) clinic in 1949. An efficiently run clinic is associated with increased cost-effectiveness by lowering preoperative admission time and thus reducing the length of stay and the associated costs. The setup of the PAT clinic should be based on the needs, culture, and resources of the institution. Various models for the setup of PAT clinic have been described, including the concept of a perioperative surgical home, which is a patient-centered model designed to improve health and the delivery of health care and to reduce the cost of care. Although there are several constraints in the development of PAT clinics, with increasing awareness about the usefulness of pre-operative risk assessments, growing bodies of literature, and evidence-based guidelines, these clinics are becoming a medical necessity for the improvement of perioperative care.
Сложность виртуальных трехмерных многообразий
Authors: Vesnin Andrei Yurievich , Turaev Vladimir Georgievich , Fominykh Evgeny Anatol'evich
Published: November 2016

Виртуальные трехмерные многообразия были введены С. В. Матвеевым в 2009 г. как естественные обобщения классических трехмерных многообразий. В настоящей работе вводится понятие сложности виртуального многообразия. Исследуется вопрос о значениях сложности виртуальных многообразий, задаваемых специальными полиэдрами с одной или двумя $2$-компонентами. На основе полученных результатов устанавливаются точные значения сложности для широкого класса трехмерных гиперболических многообразий с вполне геодезическим краем.
Библиография: 24 названия.
Almendravirus: A Proposed New Genus of Rhabdoviruses Isolated from Mosquitoes in Tropical Regions of the Americas
Authors: Contreras Maria Angelica , Eastwood Gillian , Guzman Hilda , Popov Vsevolod , Savit Chelsea , Uribe Sandra , Kramer Laura D. , Wood Thomas G. , Widen Steven G. , Fish Durland , Tesh Robert B. , Vasilakis Nikos , Walker Peter J.
Published: November 2016

The Rhabdoviridae is a diverse family of negative-sense single-stranded RNA viruses, many of which infect vertebrate hosts and are transmitted by hematophagous arthropods. Others appear to be arthropod specific, circulating only within arthropod populations. Herein, we report the isolation and characterization of three novel viruses from mosquitoes collected from the Americas. Coot Bay virus was isolated from Anopheles quadrimaculatus mosquitoes collected in the Everglades National Park, Florida; Rio Chico virus was isolated from Anopheles triannulatus mosquitoes collected in Panama; and Balsa virus was isolated from two pools of Culex erraticus mosquitoes collected in Colombia. Sequence analysis indicated that the viruses share a similar genome organization to Arboretum virus and Puerto Almendras virus that had previously been isolated from mosquitoes collected in Peru. Each genome features the five canonical rhabdovirus structural protein genes as well as a gene encoding a class 1A viroporin-like protein (U1) located between the G and L genes (3′-N-P-M-G-U1-L-5′). Phylogenetic analysis of complete L protein sequences indicated that all five viruses cluster in a unique clade that is relatively deeply rooted in the ancestry of animal rhabdoviruses. The failure of all viruses in this clade to grow in newborn mice or vertebrate cells in culture suggests that they may be poorly adapted to replication in vertebrates.
Microleakage of Glass Ionomer-based Provisional Cement in CAD/CAM-Fabricated Interim Crowns: An in vitro Study
Authors: Farah Ra'fat I , Al-Harethi Naji
Published: November 2016

Aim

The aim of this study was to compare in vitro the marginal microleakage of glass ionomer-based provisional cement with resin-based provisional cement and zinc oxide non-eugenol (ZONE) provisional cement in computer-aided design and computer-aided manufacturing (CAD/CAM)-fabricated interim restorations.

Materials and methods

Fifteen intact human premolars were prepared in a standardized manner for complete coverage of crown restorations. Interim crowns for the prepared teeth were then fabricated using CAD/CAM, and the specimens were randomized into three groups of provisional cementing agents (n = 5 each): Glass ionomer-based provisional cement (GC Fuji TEMP LT™), bisphenol-A-glycidyldimethacrylate (Bis-GMA)/triethylene glycol dimethacrylate (TEGDMA) resin-based cement (UltraTemp® REZ), and ZONE cement (TempBond NE). After 24 hours of storage in distilled water at 37°C, the specimens were thermocycled and then stored again for 24 hours in distilled water at room temperature. Next, the specimens were placed in freshly prepared 2% aqueous methylene blue dye for 24 hours and then embedded in autopolymerizing acrylic resin blocks and sectioned in buccolingual and mesiodistal directions to assess dye penetration using a stereomicroscope. The results were statistically analyzed using a nonparametric Kruskal–Wallis test. Dunn's post hoc test with a Bonferroni correction test was used to compute multiple pairwise comparisons that identified differences among groups; the level of significance was set at p < 0.05.

Results

All groups exhibited marginal microleakage; the Bis-GMA/TEGDMA resin-based provisional cement demonstrated the lowest microleakage scores, which were statistically different from those of the glass ionomer-based provisional cement and the ZONE cement.

Conclusion

The provisional cementing agents exhibited different sealing abilities. The Bis-GMA/TEGDMA resin-based provisional cement exhibited the most effective favorable sealing properties against dye penetration compared with the glass ionomer-based provisional cement and conventional ZONE cement.

Clinical significance

Newly introduced glass ionomer-based provisional cement proved to be inferior to resin-based provisional cement as far as marginal microleakage is concerned.

How to cite this article

Farah RI, Al-Harethi N. Microleakage of Glass Ionomer-based Provisional Cement in CAD/CAM-Fabricated Interim Crowns: An in vitro Study. J Contemp Dent Pract 2016;17(10):801-806.
Assessment of Interexaminer Agreement in the Detection of Condyle Morphology and positioning with Two Methods: Radiographic and Tomographic
Authors: Conti Ana CCF , Giunco JS de Almeida , Oltramari-Navarro PV Pedron , Fernandes TM Freire , Navarro R de Lima , de Almeida MR
Published: November 2016

Aim

This study aims at evaluating the interexaminer agreement between radiographic and tomographic methods to determine condyle morphological variations and positioning.

Materials and methods

The sample comprised 100 individuals aged 13 to 30 years, from the patient files of University of North Paraná. The assessment of condyles morphology and positioning was performed in images of digital panoramic radiography (DPR) and reconstructed panoramic images from the cone beam computed tomography (CBCT) scans, by using the Dolphin three-dimensional (3D) program. The condyle morphology was categorized as flat, convex, and angular as well as its positioning classified into anterior, posterior, and concentric. Three calibrated examiners performed this subjective evaluation. After that, another examiner performed an objective assessment of the condyles positioning using tomographic sagittal scans of the condyles, applying the same 3D program. This objective evaluation of the condyle position, considered the gold standard (GS), was achieved by using a formula based on the measurement values of the joint spaces, anterior and posterior. The kappa test was used to assess the interexaminer agreement in determining the condyles morphology and positioning, as well as between the condyle positioning results determined by the examiners and the GS.

Results

The results showed poor agreement among examiners and between the subjective and objective condyle positioning evaluation.

Conclusion

It was concluded that the panoramic radiography (PR), either digitalized or reconstructed from CBCT scans, is not suitable for determining variations in condyle morphology and position.

Clinical significance

Whenever it is necessary to evaluate the mandibular condyle during the orthodontic screening, the orthodontist should consider another image modality better than the PR.

How to cite this article

de Almeida Giunco JS, Oltramari-Navarro PVP, Freire Fernandes TMF, de Lima Navarro R, de Almeida MR, de Castro Ferreira Conti AC. Assessment of Interexaminer Agreement in the Detection of Condyle Morphology and positioning with Two Methods: Radiographic and Tomographic. J Contemp Dent Pract 2016;17(10):837-843.
Assessment of the Incidence of Posttreatment Endodontic Flare-ups in Patients undergoing Single-sitting Root Canal Therapies: A Clinical Study
Authors: Priyank Harsh , Devi TM Chaitra , Goel Pallavi , Sahu Nivedita , Nihalani Shweta , Shandilya Ashutosh
Published: November 2016

Introduction

Endodontic therapy is one of the commonly used procedures for treating the teeth affected by various pathologies. One of the major problems for endodontists despite the advancements in the root canal procedures is the posttreatment endodontic flare-ups. Much debate exists regarding the completion of endodontic therapy in a single sitting or multiple sittings. Hence, we assessed the incidence of endodontic flare-ups in patients undergoing single-sitting root canal therapies.

Materials and methods

The present study included 200 patients who underwent single-sitting endodontic therapy. Clinical details and conditions of each and every tooth of every patient were recorded before and after the completion of endodontic therapy. Irrigation during the root canal procedures was done by 2.5% NaOCl solution in most of the cases while others were irrigated with various combinations of ethylenediaminetetraacetic acid (EDTA) and cycloheximide (CHX) solutions. Follow-up records and readings of the patents were noted and were subjected to statistical analysis.

Results

Four groups were formed which divided the patients equally on the basis of their age. Out of 50 patients in the age group of 21 to 30 years, only 4 showed posttreatment endodontic flare-ups, while no endodontic flare-up was recorded in patients with age group of 31 to 50 years. Only two male and four females showed flare-ups postoperatively. A nonsignificant correlation was obtained when flare-up cases were compared on the basis of type of irrigation solution used during canal preparation.

Conclusion

Single-sitting endodontic therapy appears to be a successful procedure with good prognosis and minimal posttreatment flare-up results, even in patients with periapical pathologies.

Clinical significance

Single-sitting root canal procedures can be successfully carried in patients with vital or nonvital pulp tissues and also in patients with periapical lesions.

How to cite this article

Priyank H, Chaitra Devi TM, Goel P, Sahu N, Nihalani S, Shandilya A. Assessment of the Incidence of Posttreatment Endodontic Flare-ups in Patients undergoing Single-sitting Root Canal Therapies: A Clinical Study. J Contemp Dent Pract 2016;17(10):849-852.
Expression of Myofibroblasts in Oral Squamous Cell Carcinoma: An Immunohistochemical Study
Authors: Khan Javed , Prasad B Vikas , Kakatkar Gauri S , Jain Preet , Jain Meetu , Patel Maulik
Published: November 2016

Introduction

Oral squamous cell carcinoma (OSCC) is one of the most common types of malignancy affecting the orafacial region and with a high mortality rate. The fact that stroma of the tumor modulates and facilitates the progression and metastasis of the malignancy has been shown in the past studies. The cells of the activated stroma that are responsible for the progression and metastasis of the tumor are the fibroblasts having smooth muscle properties. These myofibroblasts are said to secrete numerous inflammatory mediators and factors which are said to play a crucial role in tumor progression. Therefore, we evaluated the presence of myofibroblasts in OSCC, by immunohistochemistry using alpha smooth muscle actin (α-SMA) antibody.

Materials and methods

We evaluated a total of 50 biopsy specimens from the archives of the oral pathology, where 20 specimens out of 50 were of well-differentiated OSCC (WDOSCC), 20 were of poorly differentiated OSCC (PDOSCC), and 10 were of normal healthy controls. All the specimens were stained by immunohistochemically using with monoclonal antihuman α-SMA. Etemad-Moghadam et al method was used for assessing the myofibroblast distribution. Staining index was evaluated for the groups and compared. All the results were analyzed by Statistical Package for the Social Sciences (SPSS) software.

Results

The mean percentage of myofibroblasts score for WDOSCC and PDOSCC were 2.88 and 2.92 respectively. The mean staining intensity score in WDOSCC and PDOSCC were 2.88 and 2.55 respectively. Statistically significant results were obtained while comparing the final staining index score between the OSCC group and normal control group. No significant correlation could be obtained while comparing the mean staining index score in between WDOSCC and PDOSCC.

Conclusion

Malignant epithelium might induce the adjacent stromal tissue to produce myofibroblasts. These specialized cells may be utilized as therapeutic targets for the treatment of OSCC.

Clinical significance

Proliferation of myofibroblasts may be used as a stromal marker of premalignancy and malignancy.

How to cite this article

Prasad BV, Kakatkar GS, Jain P, Jain M, Patel M, Khan J. Expression of Myofibroblasts in Oral Squamous Cell Carcinoma: An Immunohistochemical Study. J Contemp Dent Pract 2016;17(10):857-860.
Interannual variation, decadal trend, and future change in ozone outflow from East Asia
Authors: Zhu Jia , Liao Hong , Mao Yuhao , Yang Yang , Jiang Hui
Published: November 2016

Abstract. We examine the past and future changes in O3 outflow from East Asia using a global three-dimensional chemical transport model GEOS-Chem. The simulations of Asian O3 outflow for 1986–2006 are driven by the assimilated GEOS-4 meteorological fields, and those for 2000–2050 are driven by the meteorological fields archived from the Goddard Institute for Space Studies (GISS) General Circulation Model (GCM) 3 under the IPCC SRES A1B scenario. Sensitivity studies are conducted to examine the respective impacts of meteorological parameters and emissions on the variations in the outflow flux of O3. When both meteorological parameters and anthropogenic emissions varied during 1986–2006, the simulated Asian O3 outflow fluxes exhibited a small and statistically insignificant decadal trend of −2.2 % decade−1, but large interannual variations (IAVs) with seasonal absolute percent departure from the mean (APDM) values of 4–9 % and annual APDM value of 3.3 %. Sensitivity simulations indicated that the large IAVs of O3 outflow fluxes were mainly caused by the variations in meteorological conditions. The simulations of the 2000–2050 changes show that the annual outflow flux of O3 will increase by 2.0 %, 7.9 %, and 12.2 %, respectively, owing to climate change alone, emissions change alone, and changes in both climate and emissions. Therefore, climate change will aggravate the effects of the increases in anthropogenic emissions on future changes in the Asian O3 outflow. Future climate change is predicted to greatly increase Asian O3 outflow in the spring and summer seasons as a result of the projected increases in zonal winds. Findings from the present study help to understand the variations in tropospheric O3 in the downwind regions of East Asia on different timescales, and have important implications for long-term air quality planning.
A New Oxidation Flow Reactor for Measuring Secondary Aerosol
Formation of Rapidly Changing Emission Sources
Authors: Simonen Pauli , Saukko Erkka , Karjalainen Panu , Timonen Hilkka , Bloss Matthew , Aakko-Saksa Päivi , Rönkkö Topi , Keskinen Jorma , Dal Maso Miikka
Published: November 2016

Abstract. Oxidation flow reactors or environmental chambers can be used to estimate secondary aerosol formation potential of different emission sources. Emissions from anthropogenic sources, such as vehicles, often vary on short timescales. For example, to identify the vehicle driving conditions that lead to high potential secondary aerosol emissions, rapid oxidation of exhaust is needed. However, the residence times in environmental chambers and in most oxidation flow reactors are too long to study these transient effects. Here, we present a new oxidation flow reactor, TSAR (TUT Secondary Aerosol Reactor), which has a short residence time and near-laminar flow conditions. This allows studying e.g. the effect of vehicle driving conditions on secondary aerosol formation potential of the exhaust. We show that the flow pattern in TSAR is nearly laminar and particle losses are negligible. The secondary organic aerosol (SOA) produced in TSAR has a similar mass spectrum as the SOA produced in the state-of-the-art reactor, PAM (Potential Aerosol Mass). Both reactors produce the same amount of mass, but the TSAR has a higher time-resolution. We also show that the TSAR is capable of measuring secondary aerosol formation potential of a vehicle during a transient driving cycle, and that the fast response of the TSAR reveals how different driving conditions affect the amount of formed secondary aerosol. Thus, the TSAR can be used to study rapidly changing emission sources, especially the vehicular emissions during transient driving.
Detection of deterministic and probabilistic convective initiation using Himawari-8 Advanced Himawari Imager data
Authors: Lee Sanggyun , Han Hyangsun , Im Jungho , Jang Eunna , Lee Myong-In
Published: November 2016

Abstract. Detection of Convective Initiation (CI) is very important because convective clouds bring heavy rainfall and thunderstorms that typically cause severe socioeconomic damages. In this study, deterministic and probabilistic CI detection models based on decision trees (DT), random forest (RF), and logistic regression (LR) were developed using Himawari-8 Advanced Himawari Imager (AHI) data obtained from June to August 2015 over the Korean Peninsula. We used a total of 12 interest fields that contain brightness temperature, spectral differences of the brightness temperatures, and their time trends to develop CI detection models. While the interest field of 11.2 μm TB was considered the most crucial to detect CI in the deterministic models and the probabilistic RF model, the trispectral difference, i.e., (8.6–11.2 μm) − 11.2–12.4 μm), was determined as the most important one in the LR model. The performance of the four models varied by CI case and validation data. Nonetheless, the DT model typically showed higher POD, while the LR model produced higher OA and CSI and lower FAR than the other models. The CI detection of the mean lead times by the four models were in the range of 32–35 min, which implies that convective clouds can be detected in 30 min advance before precipitation intensity exceeds 35 dBZ over the Korean Peninsula in summer using the Himawari-8 AHI data is possible.
Continuous and high-precision atmospheric concentration measurements
of COS, CO2, CO and H2O using a quantum cascade laser spectrometer (QCLS)
Authors: Kooijmans Linda M. J. , Uitslag Nelly A. M. , Zahniser Mark S. , Nelson David D. , Montzka Stephen A. , Chen Huilin
Published: November 2016

Abstract. Carbonyl sulfide (COS) has been suggested as a useful tracer for gross primary production as it is taken up by plants in a similar way as CO2. To explore and verify the application of this novel tracer, it is highly desired to develop the ability to perform continuous and high-precision in situ atmospheric measurements of COS and CO2. In this study we have tested a quantum cascade laser spectrometer (QCLS) for its suitability to obtain accurate and high-precision measurements of COS and CO2. The instrument is capable of simultaneously measuring COS, CO2, CO and H2O after including a weak CO absorption line in the extended wavelength range. An optimal background and calibration strategy was developed based on laboratory tests to ensure accurate field measurements. We have derived water vapor correction factors based on a set of laboratory experiments and found that for COS the interference associated with a water absorption line can dominate over the effect of dilution. This interference can be solved mathematically by fitting the COS spectral line separately from the H2O spectral line. Furthermore, we improved the temperature stability of the QCLS by isolating it in an enclosed box and actively cooling its electronics with the same thermoelectric chiller used to cool the laser. The QCLS was deployed at the Lutjewad atmospheric monitoring station (60 m; 6°21′ E, 53°24′ N; 1 m a.s.l.) in the Netherlands from July 2014 to April 2015. The QCLS measurements of independent working standards while deployed in the field showed a mean difference with the assigned cylinder value within 3.3 ppt COS, 0.05 ppm for CO2 and 1.7 ppb for CO over a period of 35 days. The different contributions to uncertainty in measurements of COS, CO2 and CO were summarized and the overall uncertainty was determined to be 7.5 ppt for COS, 0.23 ppm for CO2 and 3.3 ppb for CO for 1-minute data. A comparison of in situ QCLS measurements with those from concurrently filled flasks that were subsequently measured by the QCLS showed a difference of −9.7 ± 4.6 ppt for COS. Comparison of the QCLS with a cavity ring-down spectrometer showed a difference of 0.12 ± 0.77 ppm for CO2 and −0.9 ± 3.8 ppb for CO.
New insights on resource stoichiometry: assessing availability of
carbon, nitrogen and phosphorus to bacterioplankton
Authors: Soares Ana R. A. , Bergström Ann-Kristin , Sponseller Ryan A. , Moberg Joanna M. , Giesler Reiner , Kritzberg Emma S. , Jansson Mats , Berggren Martin
Published: November 2016

Abstract. Boreal lake and river ecosystems receive large quantities of organic nutrients and carbon (C) from their 10 catchments. How bacterioplankton respond to these inputs is not well understood, in part because we base our understanding and predictions on "total pools", yet we know little about the stoichiometry of bioavailable elements within the organic matter. We designed bioassays with the purpose to exhaust the pools of readily bioavailable dissolved organic carbon (BDOC), bioavailable dissolved nitrogen (BDN) and bioavailable dissolved phosphorus (BDP) as fast as possible. Applying the method in four boreal lakes at base flow conditions yielded concentrations of bioavailable resources that ranged from 105–693 μg C L−1 for BDOC (2 % of total DOC), 24–288 μg N L−1 for BDN (31 % of total dissolved nitrogen) and 0.2–17 μg P L−1 for BDP (49 % of total dissolved phosphorus). Thus, relative bioavailability increased from carbon (C) to nitrogen (N) to phosphorus (P). We show that the main part of bioavailable nutrient resources is organic, representing 80 % of BDN and 61 % of BDP. In addition, we demonstrate that total C : N and C : P ratios are as much as 13-fold higher than C : N and C : P ratios for bioavailable resource fractions. Further, by applying additional bioavailability measurements to seven widely 20 distributed rivers, we provide support for a general pattern of relatively high bioavailability of P and N in relation to C. Altogether, our findings underscore the role of C as limiting factor for bacterial growth in boreal C-rich freshwaters, and suggest that these ecosystems are very sensitive to increased input of bioavailable DOC.
The Sub-Polar Gyre Index – a community data set for application in fisheries and environment research
Authors: Berx Barbara , Payne Mark R.
Published: November 2016

Abstract. Scientific interest in the sub-polar gyre of the North Atlantic Ocean has increased in recent years. The sub-polar gyre has contracted and weakened, and changes in circulation pathways have been linked to changes in marine ecosystem productivity. To aid fisheries and environmental scientists, we here present a time series of the Sub-Polar Gyre Index (SPG-I) based on monthly mean maps of sea surface height. The established definition of the SPG-I is applied, and the first EOF and PC are presented. Sensitivity to the spatial domain and time series length are explored, but found not to be important factors. Our time series compares well with indices presented previously. The SPG-I time series is freely available online (doi:10.7489/1806-1) and we invite the community to access, apply and publish studies using this index time series.
Size-resolved simulations of the aerosol inorganic composition with the new
hybrid dissolution solver HyDiS-1.0: description, evaluation and first
global modelling results
Authors: Benduhn François , Mann Graham W. , Pringle Kirsty J. , Topping David O. , McFiggans Gordon , Carslaw Kenneth S.
Published: November 2016

Abstract. The dissolution of semi-volatile inorganic gases such as ammonia and nitric acid into the aerosol aqueous phase has an important influence on the composition, hygroscopic properties, and size distribution of atmospheric aerosol particles. The representation of dissolution in global models is challenging due to inherent issues of numerical stability and computational expense. For this reason, simplified approaches are often taken, with many models treating dissolution as an equilibrium process. In this paper we describe the new dissolution solver HyDiS-1.0, which was developed for the global size-resolved simulation of aerosol inorganic composition. The solver applies a hybrid approach, which allows for some particle size classes to establish instantaneous gas-particle equilibrium, whereas others are treated time dependently (or dynamically). Numerical accuracy at a competitive computational expense is achieved by using several tailored numerical formalisms and decision criteria, such as for the time- and size-dependent choice between the equilibrium and dynamic approaches. The new hybrid solver is shown to have numerical stability across a wide range of numerical stiffness conditions encountered within the atmosphere. For ammonia and nitric acid, HyDiS-1.0 is found to be in excellent agreement with a fully dynamic benchmark solver. In the presence of sea salt aerosol, a somewhat larger bias is found under highly polluted conditions if hydrochloric acid is represented as a third semi-volatile species. We present first results of the solver's implementation into a global aerosol microphysics and chemistry transport model. We find that (1) the new solver predicts surface concentrations of nitrate and ammonium in reasonable agreement with observations over Europe, the USA, and East Asia, (2) models that assume gas-particle equilibrium will not capture the partitioning of nitric acid and ammonia into Aitken-mode-sized particles, and thus may be missing an important pathway through which secondary particles may grow to radiation- and cloud-interacting size, and (3) the new hybrid solver's computational expense is modest, at around 10 % of total computation time in these simulations.