bluuebunny/crossref_metadata_2025 huggingface dataset:
An Approach to Study Species Persistence in Unconstrained Random Networks
Authors: Fischer Samuel M. , Huth Andreas
Published: October 2019

The connection between structure and stability of ecological networks has been widely studied in the last fifty years. A challenge that scientists continue to face is that in-depth mathematical model analysis is often difficult, unless the considered systems are specifically constrained. This makes it challenging to generalize results. Therefore, methods are needed that relax the required restrictions. Here, we introduce a novel heuristic approach that provides persistence estimates for random systems without limiting the admissible parameter range and system behaviour. We apply our approach to study persistence of species in random generalized Lotka-Volterra systems and present simulation results, which confirm the accuracy of our predictions. Our results suggest that persistence is mainly driven by the linkage density, whereby additional links can both favour and hinder persistence. In particular, we observed “persistence bistability”, a rarely studied feature of random networks, leading to a dependency of persistence on initial species densities. Networks with this property exhibit tipping points, in which species loss can lead to a cascade of extinctions. The methods developed in this paper may facilitate the study of more general models and thereby provide a step forward towards a unifying framework of network architecture and stability.
Early Prediction of Soybean Traits through Color and Texture Features of Canopy RGB Imagery
Authors: Yuan Wenan , Wijewardane Nuwan Kumara , Jenkins Shawn , Bai Geng , Ge Yufeng , Graef George L.
Published: October 2019

Global crop production is facing the challenge of a high projected demand, while the yields of major crops are not increasing at sufficient speeds. Crop breeding is an important way to boost crop productivity, however its improvement rate is partially hindered by the long crop generation cycles. If end-season crop traits such as yield can be predicted through early-season phenotypic measurements, crop selection can potentially be made before a full crop generation cycle finishes. This study explored the possibility of predicting soybean end-season traits through the color and texture features of early-season canopy images. Six thousand three hundred and eighty-three images were captured at V4/V5 growth stage over 6039 soybean plots growing at four locations. One hundred and forty color features and 315 gray-level co-occurrence matrix-based texture features were derived from each image. Another two variables were also introduced to account for location and timing differences between the images. Five regression and five classification techniques were explored. Best results were obtained using all 457 predictor variables, with Cubist as the regression technique and Random Forests as the classification technique. Yield (RMSE = 9.82, R2 = 0.68), Maturity (RMSE = 3.70, R2 = 0.76) and Seed Size (RMSE = 1.63, R2 = 0.53) were identified as potential soybean traits that might be early predictable.
Mathematical modelling the pathway of genomic instability in lung cancer
Authors: Li Lingling , Zhang Xinan , Tian Tianhai , Pang Liuyong
Published: October 2019

Genomic instability plays a significant role in lung cancer. Although substantial research has been conducted using both clinical and theoretical studies, it is still a hotly debated issue to whether genomic instability is necessary or whether genomic instability precedes oncogenes activation and tumor suppressor genes inactivation for lung cancer. In response to this issue, we come up with a mathematical model incorporating effects of genomic instability to investigate the genomic instability pathway of human lung cancer. The presented model are applied to match the incidence rate data of lung cancer from the Life Span Study cohort of the atomic bomb survivors in Nagasaki and Hiroshima and the Surveillance Epidemiology and End Results registry in the United States. Model results suggest that genomic instability is necessary in the tumorigenesis of lung cancer, and genomic instability has no significant impact on the net proliferation rate of cells by statistical criteria. By comparing the results of the LSS data to those of the SEER data, we conclude that the genomic instability pathway exhibits a sensitivity to radiation exposure, more intensive in male patients.
Takayasu Arteritis with Dyslipidemia Increases Risk of Aneurysm
Authors: Pan Lili , Du Juan , Chen Dong , Zhao Yanli , Guo Xi , Qi Guanming , Wang Tian , Du Jie
Published: October 2019

Low-density lipoprotein cholesterol (LDL-C) has been associated with the occurrence of abdominal aortic aneurysm. However, whether LDL-C elevation associated with aneurysms in large vessel vasculitis is unknown. The aim of this study is to investigate the clinical and laboratory features of Takayasu arteritis (TAK) and explore the risk factors that associated with aneurysm in these patients. This retrospective study compared the clinical manifestations, laboratory parameters, and imaging results of 103 TAK patients with or without aneurysms and analyzed the risk factors of aneurysm formation. 20.4% of TAK patients were found to have aneurysms. The LDL-C levels was higher in the aneurysm group than in the non-aneurysm group (2.9 ± 0.9 mmol/l vs. 2.4 ± 0.9 mmol/l, p = 0.032). Elevated serum LDL-C levels increased the risk of aneurysm by 5.8-fold (p = 0.021, odds ratio [OR] = 5.767, 95% confidence interval [CI]: 1.302–25.543), and the cutoff value of level of serum LDL-C was 3.08 mmol/l. The risk of aneurysm was 4.2-fold higher in patients with disease duration >5 years (p = 0.042, OR = 4.237, 95% CI: 1.055–17.023), and 2.9-fold higher when an elevated erythrocyte sedimentation rate was present (p = 0.077, OR = 2.851, 95% CI: 0.891–9.115). In this study, elevated LDL-C levels increased the risk of developing aneurysms in patients with TAK.
Identification of protein-protein and ribonucleoprotein complexes containing Hfq
Authors: Caillet Joël , Baron Bruno , Boni Irina V. , Caillet-Saguy Célia , Hajnsdorf Eliane
Published: October 2019

Hfq is a RNA-binding protein that plays a pivotal role in the control of gene expression in bacteria by stabilizing sRNAs and facilitating their pairing with multiple target mRNAs. It has already been shown that Hfq, directly or indirectly, interacts with many proteins: RNase E, Rho, poly(A)polymerase, RNA polymerase… In order to detect more Hfq-related protein-protein interactions we have used two approaches, TAP-tag combined with RNase A treatment to access the role of RNA in these complexes, and protein-protein crosslinking, which freezes protein-protein complexes formed in vivo. In addition, we have performed microscale thermophoresis to evaluate the role of RNA in some of the complexes detected and used far-western blotting to confirm some protein-protein interactions. Taken together, the results show unambiguously a direct interaction between Hfq and EF-Tu. However a very large number of the interactions of proteins with Hfq in E. coli involve RNAs. These RNAs together with the interacting protein, may play an active role in the formation of Hfq-containing complexes with previously unforeseen implications for the riboregulatory functions of Hfq.
Automated and Manual Quantification of Tumour Cellularity in Digital Slides for Tumour Burden Assessment
Authors: Akbar Shazia , Peikari Mohammad , Salama Sherine , Panah Azadeh Yazdan , Nofech-Mozes Sharon , Martel Anne L.
Published: October 2019

The residual cancer burden index is an important quantitative measure used for assessing treatment response following neoadjuvant therapy for breast cancer. It has shown to be predictive of overall survival and is composed of two key metrics: qualitative assessment of lymph nodes and the percentage of invasive or in situ tumour cellularity (TC) in the tumour bed (TB). Currently, TC is assessed through eye-balling of routine histopathology slides estimating the proportion of tumour cells within the TB. With the advances in production of digitized slides and increasing availability of slide scanners in pathology laboratories, there is potential to measure TC using automated algorithms with greater precision and accuracy. We describe two methods for automated TC scoring: 1) a traditional approach to image analysis development whereby we mimic the pathologists’ workflow, and 2) a recent development in artificial intelligence in which features are learned automatically in deep neural networks using image data alone. We show strong agreements between automated and manual analysis of digital slides. Agreements between our trained deep neural networks and experts in this study (0.82) approach the inter-rater agreements between pathologists (0.89). We also reveal properties that are captured when we apply deep neural network to whole slide images, and discuss the potential of using such visualisations to improve upon TC assessment in the future.
Risk factors for immune-related adverse events associated with anti-PD-1 pembrolizumab
Authors: Eun Yeonghee , Kim In Young , Sun Jong-Mu , Lee Jeeyun , Cha Hoon-Suk , Koh Eun-Mi , Kim Hyungjin , Lee Jaejoon
Published: October 2019

We investigated risk factors for immune-related adverse events (irAEs) in patients treated with anti-programmed cell death protein1 antibody pembrolizumab. A retrospective medical record review was performed to identify all patients who received at least one dose of pembrolizumab at Samsung Medical Center, Seoul, Korea between June 2015 and December 2017. Three hundred and ninety-one patients were included in the study. Data were collected on baseline characteristics, treatment details, and adverse events. Univariate and multivariate logistic regression models were used to identify risk factors for irAEs. Sixty-seven (17.1%) patients experienced clinically significant irAEs; most commonly dermatologic disorders, followed by pneumonitis, musculoskeletal disorders, and endocrine disorders. Fourteen patients (3.6%) experienced serious irAEs (grade ≥ 3). Most common serious irAEs were pneumonitis (2.3%). Four deaths were associated with irAEs, all of which were due to pneumonitis. In multivariate regression analysis, a higher body mass index (BMI) and multiple cycles of pembrolizumab were associated with higher risk of irAEs (BMI: odds ratio [OR] 1.08, 95% confidence interval [CI] 1.01–1.16; pembrolizumab cycle: OR 1.15, 95% CI 1.08–1.22). A derived neutrophil-lymphocyte ratio (dNLR) greater than 3 at baseline was correlated with low risk of irAEs (OR 0.37, 95% CI 0.17–0.81). Our study demonstrated that an elevated BMI and higher number of cycles of pembrolizumab were associated with an increased risk of irAEs in patients treated with pembrolizumab. Additionally, increased dNLR at baseline was negatively correlated with the risk of developing irAEs.
A novel multi-parametric analysis of non-invasive methods to assess animal distress during chronic pancreatitis
Authors: Abdelrahman Ahmed , Kumstel Simone , Zhang Xianbin , Liebig Marie , Wendt Edgar Heinz Uwe , Eichberg Johanna , Palme Rupert , Thum Thomas , Vollmar Brigitte , Zechner Dietmar
Published: October 2019

Ethical responsibility, legal requirements and the need to improve the quality of research create a growing interest in the welfare of laboratory animals. Judging the welfare of animals requires readout parameters, which are valid and sensitive as well as specific to assess distress after different interventions. In the present study, we evaluated the sensitivity and specificity of different non-invasive parameters (body weight change, faecal corticosterone metabolites concentration, burrowing and nesting activity) by receiver operating characteristic curves and judged the merit of a multi-parametric analysis by logistic regression. Chronic pancreatitis as well as laparotomy caused significant changes in all parameters. However, the accuracy of these parameters was different between the two animal models. In both animal models, the multi-parametric analysis relying on all the readout parameters had the highest accuracy when predicting distress. This multi-parametric analysis revealed that C57BL/6 mice during the course of chronic pancreatitis often experienced less distress than mice after laparotomy. Interestingly these data also suggest that distress does not steadily increase during chronic pancreatitis. In conclusion, combining these non-invasive methods for severity assessment represents a reliable approach to evaluate animal distress in models such as chronic pancreatitis.
A family of orthologous proteins from centipede venoms inhibit the hKir6.2 channel
Authors: Ramu Yajamana , Lu Zhe
Published: October 2019

Inhibitors targeting ion channels are useful tools for studying their functions. Given the selectivity of any inhibitor for a channel is relative, more than one inhibitor of different affinities may be used to help identify the channel in a biological preparation. Here, we describe a family of small proteins in centipede venoms that inhibit the pore (hKir6.2) of a human ATP-sensitive K+ channel (hKATP). While the traditional peptide-sequencing service gradually vanishes from academic institutions, we tried to identify the sequences of inhibitory proteins purified from venoms by searching the sequences of the corresponding transcriptomes, a search guided by the key features of a known hKir6.2 inhibitor (SpTx1). The candidate sequences were cross-checked against the masses of purified proteins, and validated by testing the activity of recombinant proteins against hKir6.2. The four identified proteins (SsdTx1-3 and SsTx) inhibit hKATP channels with a Kd of <300 nM, compared to 15 nM for SpTx1. SsTx has previously been discovered to block human voltage-gated KCNQ K+ channels with a 2.5 μM Kd. Given that SsTx inhibits hKir6.2 with >10-fold lower Kd than it inhibits hKCNQ, SsTx may not be suitable for probing KCNQ channels in a biological preparation that also contains more-SsTx-sensitive KATP channels.
Germylene stabilized group 12 metal complexes and their reactivity with chalcogens
Authors: Sinhababu Soumen , Sharma Mahendra Kumar , Mahawar Pritam , Kaur Supreet , Singh Vivek Kumar , Paliwal Akhil , Yadav Dhirendra , Kashyap Hemant K. , Nagendran Selvarajan
Published: October 2019

This manuscript reports the first examples of germylene stabilized cadmium complexes 3, 6, and 7, and novel germylene zinc complexes 2 and 5.
Facile creation of hierarchical nano-sized ZSM-5 with a large external surface area via desilication–recrystallization of silicalite-1 for conversion of methanol to hydrocarbons
Authors: Shao Juan , Fu Tingjun , Ma Zhe , Zhang Chunmei , Li Han , Cui Liping , Li Zhong
Published: October 2019

Mesoporous ZSM-5 with large external surface and strong acidity were created through desilication–recrystallization of nano-sized silicalite-1, and the catalytic lifetime of its regenerated catalyst is 2.5 times longer than fresh catalyst.
Structural evolution of Ag/BN hybrids via a polyol-assisted fabrication process and their catalytic activity in CO oxidation
Authors: Konopatsky Anton S. , Firestein Konstantin L. , Leybo Denis V. , Sukhanova Ekaterina V. , Popov Zakhar I. , Fang Xiaosheng , Manakhov Anton M. , Kovalskii Andrey M. , Matveev Andrei T. , Shtansky Dmitry V. , Golberg Dmitri V.
Published: October 2019

Enhanced catalytic activity of Ag/BN nanohybrids is ascribed to the formation of a thin intermediate Ag–O–B layer.
Complementary bonding analysis of the N–Si interaction in pentacoordinated silicon compounds using quantum crystallography
Authors: Fugel Malte , Ponomarenko Maksym V. , Hesse Maxie F. , Malaspina Lorraine A. , Kleemiss Florian , Sugimoto Kunihisa , Genoni Alessandro , Röschenthaler Gerd-Volker , Grabowsky Simon
Published: October 2019

The unique combination of quantum crystallography and complementary bonding analysis is used to investigate the bonding of pentacoordinated silicon atoms.
A general benzylic C–H activation and C–C coupling reaction of zirconocenes mediated by C–N bond cleavage in tert-butylisocyanide – unusual formation of iminoacyl complexes
Authors: Arndt Perdita , Reiß Melanie , Spannenberg Anke , Schünemann Claas , Reiß Fabian , Beweries Torsten
Published: October 2019

Reactions of the zirconocene alkyne complex [rac-(ebthi)Zr(η2-Me3SiC2SiMe3)] (rac-(ebthi) = rac-1,2-ethylene-1,1′-bis(η5-tetrahydroindenyl)) with tert-butylisocyanide and methylbenzenes were investigated.
Ionic liquids with polychloride anions as effective oxidants for the dissolution of UO2
Authors: Yao Aining , Qu Feng , Liu Yu , Qu Guangyin , Lin Hao , Hu Shaowen , Wang Xiangyun , Chu Taiwei
Published: October 2019

Polychloride ionic liquids can not only successfully dissolve UO2, but also raise the chlorine efficiency.
Simultaneous energy harvesting and storage via solar-driven regenerative electrochemical cycles
Authors: Ding Yu , Guo Xuelin , Ramirez-Meyers Katrina , Zhou Yangen , Zhang Leyuan , Zhao Fei , Yu Guihua
Published: October 2019

An innovative energy system integrating energy conversion and storage is designed to achieve cost-effective harnessing of solar energy and thermal energy.
Conjugated polymers for visible-light-driven photocatalysis
Authors: Dai Chunhui , Liu Bin
Published: October 2019

This review summarizes the recent advancements in π-conjugated polymers for various photocatalytic applications under visible light.
Aptamer-functionalized exosomes from bone marrow stromal cells target bone to promote bone regeneration
Authors: Luo Zhong-Wei , Li Fu-Xing-Zi , Liu Yi-Wei , Rao Shan-Shan , Yin Hao , Huang Jie , Chen Chun-Yuan , Hu Yin , Zhang Yan , Tan Yi-Juan , Yuan Ling-Qing , Chen Tuan-Hui , Liu Hao-Ming , Cao Jia , Liu Zheng-Zhao , Wang Zhen-Xing , Xie Hui
Published: October 2019

A novel strategy to deliver therapeutic exosomes to bone is developed for the first time by conjugating a specific BMSC-targeting aptamer to the exosomal surface.
Cell membrane based biomimetic nanocomposites for targeted therapy of drug resistant EGFR-mutated lung cancer
Authors: Wu Pengying , Yin Dongtao , Liu Jiaming , Zhou Huige , Guo Mengyu , Liu Jing , Liu Yang , Wang Xiaobing , Liu Ying , Chen Chunying
Published: October 2019

A cancer cell membrane-based biomimetic strategy was developed by loading doxorubicin and icotinib to overcome drug-resistance of EGFR-mutation lung cancer.
Screening the 4f-electron spin of TbPc2 single-molecule magnets on metal substrates by ligand channeling
Authors: Barhoumi Rabei , Amokrane Anis , Klyatskaya Svetlana , Boero Mauro , Ruben Mario , Bucher Jean-Pierre
Published: October 2019

Tuning the magnetic Kondo screening of the 4f-electron moment in TbPc2 double-deckers upon controlled molecule–substrate interaction.
A high-power lithium-ion hybrid capacitor based on a hollow N-doped carbon nanobox anode and its porous analogue cathode
Authors: Liang Tian , Wang Huanwen , Fei Rixin , Wang Rui , He Beibei , Gong Yansheng , Yan Chunjie
Published: October 2019

A novel “dual carbon” lithium-ion hybrid capacitor configuration is designed by using an anode of a hollow nitrogen-doped carbon nanobox and its porous analogue cathode.
Electronic modulation of composite electrocatalysts derived from layered NiFeMn triple hydroxide nanosheets for boosted overall water splitting
Authors: Yan Lei , Ren Yanrong , Zhang Xiaolong , Sun Yulin , Ning Jiqiang , Zhong Yijun , Teng Botao , Hu Yong
Published: October 2019

Fe and Mn co-doped Ni3S2 nanosheet arrays (FM-NS NSAs) and layered NiFeMn triple hydroxide (NiFeMn-LTH)/FM-NS hybrid NSAs can be employed as OER and HER electrodes for boosted overall water splitting.
Correction: A series of red iridium(iii) complexes using flexible dithiocarbamate derivatives as ancillary ligands for highly efficient phosphorescent OLEDs
Authors: Lu Guang-Zhao , Wu Ruixia , Liu Liang , Zhou Liang , Zheng You-Xuan , Zhang Wen-Wei , Zuo Jing-Lin , Zhang Hongjie
Published: October 2019

Correction for ‘A series of red iridium(iii) complexes using flexible dithiocarbamate derivatives as ancillary ligands for highly efficient phosphorescent OLEDs’ by Guang-Zhao Lu et al., Mater. Chem. Front., 2019, 3, 860–866.
Brittle solid collapse to simple liquid for a waxy suspension
Authors: Andrade Diogo E. V. , Coussot Philippe
Published: October 2019

Waxy oils initially solid (left) undergo an abrupt transition to liquid after a simple shock (successive pictures on the right).
A metaheuristic penalty approach for the starting point in nonlinear programming
Authors: Penas David R. , Raydan Marcos
Published: October 2019

Solving nonlinear programming problems usually involve difficulties to obtain a starting point that produces convergence to a local feasible solution, for which the objective function value is sufficiently good. A novel approach is proposed, combining metaheuristic techniques with modern deterministic optimization schemes, with the aim to solve a sequence of penalized related problems to generate convenient starting points. The metaheuristic ideas are used to choose the penalty parameters associated with the constraints, and for each set of penalty parameters a deterministic scheme is used to evaluate a properly chosen metaheuristic merit function. Based on this starting-point approach, we describe two different strategies for solving the nonlinear programming problem. We illustrate the properties of the combined schemes on three nonlinear programming benchmark-test problems, and also on the well-known and hard-to-solve disk-packing problem, that possesses a huge amount of local-nonglobal solutions, obtaining encouraging results both in terms of optimality and feasibility.
Die neuen Leitlinien zur Überprüfung von Heilpraktikeranwärtern
Authors: Lubbe Reinhard
Published: October 2019

Am 23. Dezember 2016 wurde vom Bundestag das „Dritte Gesetz zur Stärkung der pflegerischen Versorgung und zur Änderung weiterer Vorschriften“ verabschiedet. Unter Artikel 17e und 17 f findet sich eine Änderung des Heilpraktikergesetzes und der ersten Durchführungsverordnung zum Heilpraktikergesetz. In letzterer wird das Bundesministerium für Gesundheit beauftragt Leitlinien zur Überprüfung von Heilpraktikeranwärtern *  zu erstellen. Dies erfolgte und die Leitlinien sind seit dem 22.3.2018 in Kraft 1. Am grundsätzlichen rechtlichen Konstrukt des Heilpraktikerwesens (Ordnungsrechtliche Genehmigung; Gefahrenausschluss) wurde nichts geändert.
Die Nachsorge des Lungenkarzinoms
Authors: Tufman Amanda , Duell Thomas , Schneider Christian
Published: October 2019

Ziel dieses Beitrags ist es, die aktuellen Leitlinien bzw. Empfehlungen zur Nachsorge des Lungenkarzinoms zu präsentieren und eine evidenzbasierte Herangehensweise für die Erstellung von individualisierten Nachsorgepläne aufzuzeigen.
Clinical Study on Minimally Invasive Liquefaction and Drainage of Hypertensive Putaminal Hemorrhage through Frontal Approach
Authors: W. Gong , J. Ma
Published: October 2019

Background Hypertensive intracerebral hemorrhage is one of the most common cerebrovascular diseases with high mortality and high disability rate. The aim of this study was to observe the curative effect of minimally invasive liquefaction and drainage of hypertensive putaminal hemorrhage (HPH) through frontal approach.

Methods This study retrospectively reviewed the clinical data of 66 HPH patients who underwent surgery from January 2012 to January 2017 including 35 males and 31 females, aged 51 to 82 years, with an average age of 61.6 ± 7.32 years. All patients were treated in the first people’s hospital of Kunshan. They were divided into two groups: puncture thrombolysis and drainage therapy (PTDT) group and conventional craniotomy (CC) group.

Result The pulmonary infection rate in PTDT group was 13.8%, significantly lower than that of 27.7% in CC group (p < 0.05). One year after onset, the modified Rankin scale (mRS) score of surviving patients was evaluated. The mRS score of the PTDT group with 30 to 60 mL of preoperative bleeding was 1.91 ± 0.82, which was significantly better than that of the CC group (2.21 ± 0.83) (p < 0.05). There was no significant difference in mRS score between PTDT group (2.59 ± 0.62) and CC group (2.88 ± 0.87) with preoperative bleeding > 60 mL (p > 0.05). In patients with Glasgow coma scale (GCS) 5 to 8 scores, the mRS of PTDT and CC groups were 2.73 ± 0.72 and 2.94 ± 0.96, respectively (p > 0.05). In patients with GCS 9 to 13 scores, the mRS score of PTDT group was 1.83 ± 0.69, which was significantly better than that of CC group (2.06 ± 0.74) (p < 0.05).

Conclusion HPH can be treated effectively through PTDT. PTDT group has lower lung infection rate than CC group. And it can significantly improve the prognosis of patients with preoperative bleeding volume of 30 to 60 mL and preoperative GCS score of 9 to 13.
Clinical Evaluation of Resin-Based Composites in Posterior Restorations: 12-Month Results
Authors: Celik Cigdem , Arhun Neslihan , Yamanel Kivanc
Published: October 2019

Objectives: The purpose of this study was to evaluate and compare the 12 month clinical performances of two different posterior composites in Class I and Class II restorations.

Methods: Thirty-one patients (10 male, 21 female) were recruited into the study. A total of 82 Class I and Class II cavities were restored with either a nanohybrid composite (Grandio) or a low-shrinkage composite (Quixfil), using their self etch adhesives (Futura Bond and Xeno III) according to manufacturers instructions. The restorations were clinically evaluated 1 week after placement as baseline, and after 6 and 12 months post-operatively using modified USPHS criteria by two previously calibrated operators. Statistical analysis were performed using Pearson Chi-square and Fishers Exact Test (P<.05).

Results: All patients attended the 12-month recall. Lack of retention was not observed in any of the restorations. With respect to color match, marginal adaptation, secondary caries and surface texture, no significant differences were found between two restorative materials tested after 12 months (P>.05). None of the restorations had marginal discoloration and anatomic form loss on the 12 month follow-up. Restorations did not exhibit post-operative sensitivity at any evaluation period.

Conclusions: Clinical assessment of nanohybrid (Grandio) and low-shrinkage posterior composite (Quixfil) exhibited good clinical results with predominating alpha scores after 12 months. However; further evaluations are necessary for the long-term clinical performance of these materials. (Eur J Dent 2010;4:57-65)
Evaluation of the Friction of Self-Ligating and Conventional Bracket Systems
Authors: Tecco Simona , Iorio Donato Di , Nucera Riccardo , Bisceglie Beatrice Di , Cordasco Giancarlo , Festa Felice
Published: October 2019

Objectives: This in vitro study evaluated the friction (F) generated by aligned stainless steel (SS) conventional brackets, self-ligating Damon MX© brackets (SDS Ormco, Glendora, California, USA), Time3© brackets (American Orthodontics, Sheboygan, Wisconsin, USA), Vision LP© brackets (American Orthodontics), and low-friction Slide© ligatures (Leone, Firenze, Italy) coupled with various SS, nickel-titanium (NiTi), and beta-titanium (TMA) archwires. Methods: All brackets had a 0.022-inch slot, and the orthodontic archwires were 0.014-inch, 0.016-inch, 0.014×0.025-inch, 0.018×0.025-inch, and 0.019×0.025-inch NiTi; 0.017×0.025-inch TMA; and 0.019×0.025-inch SS. Each bracket-archwire combination was tested 10 times. In the test, 10 brackets of the same group were mounted in alignment on a metal bar. The archwires moved through all the 10 brackets at a crosshead speed of 0.5 mm/min (each run lasted approximately 5 min). The differences among 5 groups of brackets were analyzed through the Kruskal-Wallis test, and a Mann-Whitney test was calculated as post hoc analysis. The P value was set at 0.05. Results: Coupled with 0.014-inch NiTi and 0.016-inch NiTi, Victory Series© brackets generated the greatest F, while Damon MX© and Vision LP© brackets generated the lowest (P<.05); no significant differences were observed between Time3© brackets and Slide© ligatures. Coupled with all the rectangular archwires, Victory Series© brackets, Slide© ligatures, and Vision LP© self-ligating brackets generated significantly lower F than did Time3© and Damon MX© self-ligating brackets (P<.05). Conclusions: These findings suggest that self-ligating brackets are a family of brackets that, in vitro, can generate different levels of F when coupled with thin or thick, rectangular, or round archwires. Clinical conclusions based on our results are not possible due to the limitations of the experimental conditions. (Eur J Dent 2011;5:310-317)
Quality of Root Canal Fillings Performed by Undergraduate Dental Students
Authors: Unal Gul Celik , Kececi Ayse Diljin , Kaya Bulem Ureyen , Tac Ali Gurhan
Published: October 2019

Objectives: The purpose of this study was to evaluate the radiographic quality of root canal fillings performed by first and second clinical year dental students at the Faculty of Dentistry in Süleyman Demirel University, Turkey. Methods: The technical quality of 833 root canal fillings was evaluated by three examiners according to the density of the filling and the distance between the end of the filling and the radiographic apex. A root canal with acceptable filling length and homogeneous root filling was defined as being good quality endodontic work (GQEW). A treated tooth was defined as having good quality endodontic work tooth (GQEW-T) when all its canals had a GQEW rating. Results: A Chi-square (χ2) test at the 0.05 significance level was used for the statistical analysis of the data. Of a total of 833 root canals, 662 (79.47%) root fillings were classed as GQEW. Two hundred fifty canals (73.4%) (135 teeth) treated by first clinical year dental students were defined as GQEW-T while 412 canals (204 teeth) (73.9%) treated by second clinical year dental students were defined as GQEW-T (P>.05). Most of the GQEW-T were defined in anterior teeth (90.1%), whereas the fewest were in molar teeth (46.6%) for both first and second clinical year dental students (P<.001). Conclusions: The quality of root canal fillings in anterior teeth performed by undergraduate dental students in Isparta, Turkey was satisfactory. However, to improve the success with molar teeth, education about newer techniques and instruments must be incorporated into the preclinical and clinical curriculum. (Eur J Dent 2011;5:324-330)
The Effect of Investment Materials on the Color of Feldspathic Ceramics
Authors: Azevedo Cubas Gloria Beatriz de , Fontes Sílvia Terra , Camacho Guilherme Brião , Demarco Flávio Fernando , Pereira-Cenci Tatiana
Published: October 2019

Objectives: The aim of this study was to evaluate the influence of investment type on the color of feldspathic ceramics. Methods: Ceramic specimens were constructed using the refractory die technique, using four investments (i.e., Vitadurvest, Duravest, Duceralay Superfit, and Fortune) to observe their effect on the color of five commercially available ceramics (i.e., Super Porcelain EX-3, Vision Esthetic, Vintage Halo, IPS Classic, and Vitadur Alpha). The color analysis of the ceramics was performed with a colorimeter using the CIE L*a*b* color coordinates. Results: The investments produced significant alterations on a*, b*, and L* color parameters of the ceramics tested. The ceramic Vision Esthetic was influenced by the type of investment in all color parameters (P<.05). Two investments (Duravest and Fortune) produced alterations in color parameters with three of the five ceramics tested. Conclusions: The investment materials produced alterations on the ceramic color parameters, resulting in unacceptable chromatic alterations (ΔE*). (Eur J Dent 2011;5:433-440)
Color and opacity of composites protected with surface sealants and submitted to artificial accelerated aging
Authors: Aguilar Fabiano Gamero , Roberti Garcia Lucas da Fonseca , Cruvinel Diogo Rodrigues , Silva Sousa Ana Beatriz , Pires-de-Souza Fernanda de Carvalho Panzeri
Published: October 2019

Objectives: To evaluate the color similarity, stability and opacity of composites (TPH, Charisma, and Concept, shade A2) protected with surface sealants (Fortify Plus and Biscover) and cyanoacrylate (Super Bonder).

Methods: Forty specimens of each composite were made and separated into 4 groups (n=10) according to the surface protection: GI - without sealant; GII - cyanoacrylate; GIII - Fortify Plus; GIV - Biscover. Color and opacity readings were taken before and after Artificial Acelerated Aging (AAA) and the values obtained for color stability were submitted to statistical analysis by 2-way ANOVA and Bonferroni’s test (P<.05). The values acquired for color similarity were submitted to 1-way ANOVA and Tukey’s test (P<.05). The specimen sufaces were compared before and after AAA using Scanning Electronic Microscopy (SEM).

Results: Studied composites did not present the same values for the coordinates L*, a* and b * before AAA, indicating that there was no color similarity among them. All composites presented color alteration after AAA with clinically unacceptable values. Protected groups presented lower opacity variation after AAA, in comparison with the control goup. SEM evaluation demonstrated that AAA increased the surface irregularities in all of the studied groups.

Conclusion: Surface sealants were not effective in maintaining composite color, but were able to maintain opacity. (Eur J Dent 2012;6:24-33)
Conservative reconstruction of the smile by orthodontic, bleaching, and restorative procedures
Authors: Sundfeld Renato Herman , Machado Lucas Silveira , de Oliveira Fernanda Garcia , Santos Eduardo Almada , Lugato Isabel Cristina Prado Torres , Neto Daniel Sundfeld
Published: October 2019

The following is a clinical case report of a patient whose chief complaint was the presence of generalized spacing in the maxillary anterior segment following orthodontic treatment. After meticulous clinical analyses and discussions of the clinical procedures to be adopted, dental bleaching was performed in both arches with 10% hydrogen peroxide (Opalescence Trèswhite Supreme 10% Hydrogen Peroxide - Ultradent Products, Inc., South Jordan, USA) after the conclusion and stabilization of orthodontic treatment. Then, the orthodontic appliance was removed and the diastemas in the maxillary anterior teeth were closed with Amelogen Plus (Ultradent Products, Inc., South Jordan, USA) resin composite. It was observed that the association of orthodontic, bleaching, and restorative procedures was capable of restoring dental shape, function, and esthetics, allowing the patient to smile without hesitation. (Eur J Dent 2012;6:105-109)
Radiopacity evaluation of composite restorative resins and bonding agents using digital and film x-ray systems
Authors: Oztas Bengi , Kursun Sebnem , Dinc Gul , Kamburoglu Kıvanc
Published: October 2019

Objective: The purpose of this in vitro study was to explore the radiopacity of composite resins and bonding materials using film and phosphor plates.

Methods: Nine composite dental resin specimens and human tooth slices were exposed together with an aluminium stepwedge using dental film and phosphor plates. Eight dentin bonding specimens were prepared and exposed in a similar manner. Their radiopacity on film was assessed using a transmission densitometer, and the radiopacity with phosphor plates was assessed digitally using the system’s own software (Digora). Data were analysed using one-way analysis of variance (ANOVA) and post-hoc Tukey tests (P<.05). Film and phosphor plate radiopacity values were compared using simple regression analysis

Results: Excellent linear correlation was found between film and phosphor plates for both composite resins and bonding agents. The composite materials Spectrum Tph and Natural Look exhibited the highest radiopacity with film and with phosphor plates, respectively. All the dentin bonding agents tested exhibited lower radiopacity than dentin. Conclusion: Synergy, Ice, Filtek Silorane, Filtek Z250, Clearfil Majesty Posterior, Herculite Classic, Spectrum Tph, and Natural Look composite materials exhibited greater radiopacity than dentin, and all the dentin bonding agents tested exhibited lower radiopacity than either enamel or dentin. (Eur J Dent 2012;6:115-122)
Multidisciplinary treatment of non-syndromic oligodontia
Authors: Bural Canan , Oztas Evren , Ozturk Sukru , Bayraktar Gulsen
Published: October 2019

Oligodontia is the agenesis of 6 or more teeth, excluding third molars. The etiology of congenital absence of teeth is believed to be rooted in heredity or developmental anomalies. The absence of teeth in patients can cause aesthetic, functional, and psychological problems, particularly if the anterior region is involved. This case report describes the multidisciplinary treatment approach toward a patient 17 years of age with non-syndromic oligodontia, with absence of 11 permanent teeth. Genetic counseling revealed non-syndromic, autosomal-recessive-linked oligodontia. The objectives of the first phase of therapy were pre-prosthetic orthodontic space opening for proper positioning of the missing teeth and correction of inter-maxillary relations, as a prerequisite for proper prosthetic restoration. The second phase of therapy was prosthetic restoration of the missing teeth and provision of occlusion with full-mouth porcelain fused to metal crowns and bridges after increasing occlusal vertical dimension by 2 mm. (Eur J Dent 2012;6:218-226)
In vivo assessment of secondary caries and dentin characteristics after traditional amalgam restorations
Authors: Pinheiro Isauremi Vieira de Assunção , Borges Boniek Castillo Dutra , de Lima Kenio Costa
Published: October 2019

Objectives:This study aimed to evaluate in vivo the occurrence of secondary caries and dentin characteristics in permanent molars after traditional amalgam restorations, by means of clinical visual examination, radiographs and laser-induced fluorescence (LF) (DIAGNOdent).

Methods:Thirty first permanent molars of 30 schoolchildren in the 7 to14 year-old age group were included. Caries was removed by hand. Thus, indirect pulp capping was performed with glassionomer cement (GIC), the cavity was varnished and amalgam filled. LF was measured before and after cavity preparation and after a 12-month observation period. Dentin color after cavity preparation and after the 12-month observation period was recorded. Recurrent caries was also investigated by visual clinical and radiographic examinations, in addition to dentin thickness between pulp and indirect GIC pulp capping. Data was analyzed by ANOVA for repeated measurements, paired “t” test and descriptive statistic.

Results:There were statistically significant differences (P<.05) among LF scores for dentin in all periods evaluated, with the lowest scores shown after 12 month of observation. There was no statistical difference between dentin color after cavity preparation and following 12 months of observation. Moreover, there was no recurrent caries attack at 12-month follow-up; dentin thickness between pulp and indirect GIC pulp capping was similar between baseline and final observation periods. It was concluded that the clinical restorative procedure using hand caries removal, indirect pulp capping with GIC, varnishing and amalgam filling the cavity did not provide secondary caries and increased dentin mineral content after 12 months. (Eur J Dent 2012;6:263-269)
Dislocation reduction in AlInSb mid-infrared photodiodes grown on GaAs substrates
Authors: Fujita H. , Nakayama M. , Morohara O. , Geka H. , Sakurai Y. , Nakao T. , Yamauchi T. , Suzuki M. , Shibata Y. , Kuze N.
Published: October 2019

We investigated the electrical and optical properties of a highly mismatched AlInSb/GaAs photodiode sensor working in the mid-infrared range at room temperature. A substantial increase in the device performance was achieved by controlling the strain energy density in the dislocation filter layers and barrier layers to reduce the density of threading and interfacial dislocations, respectively. The resulting photodiode showed a high resistance-area product of 0.24 Ω cm2 and a peak detectivity of 2.2 × 109 cm Hz1/2 W–1 at 3.3 μm.
Shear-induced platelet aggregation: 3D-grayscale microfluidics for repeatable and localized occlusive thrombosis
Authors: Griffin Michael T. , Kim Dongjune , Ku David N.
Published: October 2019

Atherothrombosis leads to complications of myocardial infarction and stroke as a result of shear-induced platelet aggregation (SIPA). Clinicians and researchers may benefit from diagnostic and benchtop microfluidic assays that assess the thrombotic activity of an individual. Currently, there are several different proposed point-of-care diagnostics and microfluidic thrombosis assays with different design parameters and end points. The microfluidic geometry, surface coatings, and anticoagulation may strongly influence the precision of these assays. Variability in selected end points also persists, leading to ambiguous results. This study aims to assess the effects of three physiologically relevant extrinsic design factors on the variability of a single end point to provide a quantified rationale for design parameter and end-point standardization. Using a design of experiments approach, we show that the methods of channel fabrication and collagen surface coating significantly impact the variability of occlusion time from porcine whole blood, while anticoagulant selection between heparin and citrate did not significantly impact the variability. No factor was determined to significantly impact the mean occlusion time within the assay. Occlusive thrombus was found to consistently form in the first third (333 μm) of the high shear zone and not in the shear gradient regions. The selection of these factors in the design of point-of-care diagnostics and experimental SIPA assays may lead to increased precision and specificity in high shear thrombosis studies.
Understanding the multi-mass model and sound generation of vocal fold oscillation
Authors: Park Myung-cheol
Published: October 2019

When a speaker speaks, the vocal fold oscillates, generating a voice. The voice resonating in the vocal tract and in the mouth is converted to speech when the speaker changes the shapes of the mouth and tongue. When the vocal fold oscillates, a voice is generated because the vocal fold oscillation vibrates the air in succession, and the vocal fold oscillation triggers the generation of the fundamental frequency of the vocal fold as well as that of the harmonic sound at the same time. It is not easy to understand these sound generation principles acoustically, however, unless one is equipped with deep knowledge in the fields of physics and acoustics. In this paper, therefore, the vocal fold will be simplified as a multi-mass model, and a way to easily understand the principle that the fundamental frequency and harmonic sound are generated simultaneously by vocal fold oscillation will be presented.
Measurement of electron temperature in a non-equilibrium discharge of atmospheric pressure supported by focused microwave radiation from a 24 GHz gyrotron
Authors: Sintsov Sergey , Vodopyanov Alexander , Mansfeld Dmitry
Published: October 2019

A microwave discharge of atmospheric pressure, maintained by focused CW radiation of a 24-GHz gyrotron in an argon flow in an external air atmosphere, was investigated. The electron temperature was determined by the current-voltage curve of a dual Langmuir probe placed in a plasma torch. The electron temperature was also estimated from plasma emission spectra within the framework of a coronal plasma model. The obtained values of the electron temperature coincide within the measurement accuracy. Also, the electron temperature is many times higher than the gas temperature. This fact allows us to stand of a significantly non-equilibrium atmospheric pressure plasma.
Wind analysis links West Antarctic ice loss to humans
Authors: Lopatka Alex
Published: October 2019

Anthropogenic warming is reversing the predominant winds over the region and could explain the ice sheet’s destabilization.
Teaching physics for tomorrow: Equipping students to change the world
Authors: Bailey Crystal , Arion Douglas
Published: October 2019

Why should engineers have all the fun?
Release of technology critical metals during sulfide oxidation processes: the case of the Poderosa sulfide mine (south-west Spain)
Authors: Cánovas Carlos Ruiz , Macías Francisco , Olías Manuel , Basallote Maria Dolores , Pérez-López Rafael , Ayora Carlos , Nieto Jose Miguel
Published: October 2019

Environmental contextNatural weathering of rocks may release technology critical elements (TCEs) to the environment, and anthropogenic activities can noticeably increase TCE release rates. We investigated acid mine drainage outflows from an underground sulfide mine in south-west Spain, reporting TCE concentrations orders of magnitude higher than those observed in natural waters. The findings improve our knowledge on mobility of TCEs in different geological settings.
AbstractExtensive extraction of technology critical elements (TCEs) from the lithosphere and their use results in a growing dispersion and remobilisation of these elements within the environmental compartments. We investigated the concentration and mobility of different TCEs (rare earth elements (REEs), Sc, Y, Ga and Tl) in acid mine drainage (AMD) outflows from a massive sulfide underground mine in south-west Spain for around 2 years. High levels of TCEs were observed; average concentrations of 8.2mgL−1 of REEs, 1.5mgL−1 of Y, 80µgL−1 of Ga, 53µgL−1 of Sc and 42µgL−1 of Tl were reported, several orders of magnitude higher than those observed in natural waters. The TCEs source in the study site is primarily accessory minerals in the host rocks, although the contribution of Ga and Tl by sulfides cannot be discarded. A seasonal variability in TCEs is observed in AMD waters, although their maximum concentrations do not coincide with those of sulfide-related elements. TCEs seem not to be controlled by the precipitation of secondary minerals, but by the intensity of chemical weathering inside the mined zone. A positive correlation between REEs and the Si/Na+K ratio seems to indicate that these elements are linked to resistant minerals to weathering.
Fate of steroid hormone micropollutant estradiol in a hybrid magnetic ion exchange resin-nanofiltration process
Authors: Imbrogno Alessandra , Samanta Prantik , Schäfer Andrea I.
Published: October 2019

Environmental contextContamination of surface water by micropollutants is a major environmental concern because of their high persistence and toxicity. Micropollutants are only partially removed in nanofiltration water treatment systems, encouraging the investigation of more complex systems involving partitioning with membrane materials, organic matter and ion exchange resins. This study elucidates the micropollutant partitioning mechanisms in this complex water treatment system. AbstractThe accumulation of micropollutants, such as steroid hormones, in magnetic ion exchange resin-nanofiltration (MIEX-NF) poses a risk to the environmental contamination of surface water where the treated water is discharged. In this study, the partitioning of the steroid hormone estradiol (E2) with humic acid (HA), MIEX and the membrane is investigated at different feed water conditions (e.g. pH and presence of calcium). The transport and adsorption of E2 in NF is not affected significantly by the E2-HA interaction. Indeed, E2 partitions with HA between 8% and 25% at different pH. This is attributed to the presence of calcium ions, which reduces the number of HA molecules available to interact with E2 molecules. The calcium interference is evident especially at pH>10, where calcite and HA precipitate to result in irreversible membrane fouling. In the hybrid MIEX-NF process, the E2-MIEX interaction occurs at all pH conditions. Approximately 40% of the E2 total mass partitions with MIEX. This is significantly higher than E2 accumulation in NF. Since the partitioning is at least partially reversible, this poses a risk for accidental E2 release into the process streams.