bluuebunny/crossref_metadata_2025 huggingface dataset:
Unexpected ischemia during transcatheter patent arterial duct closure
Authors: Materna Ondrej , Suchanek Vojtech , Reich Oleg
Published: September 2019

A child undergoing routine transcatheter patent arterial duct closure developed severe transient ischemic changes in the electrocardiogram (Pardee waves) while the aortic retention skirt of the Amplatzer™ Duct Occluder was pulled against the duct orifice. The occluder was then released, and the delivery system was pulled back to inferior caval vein which led to electrocardiogram normalisation. Aortic root angiography showed a single coronary artery originating from the right sinus of Valsalva with the left coronary stem wedged behind the posterior aspect of the right ventricular outflow tract. We believe that the left coronary artery was compressed while applying tension on the occluder delivery system.
Why do parties support emigrant voting rights?
Authors: Østergaard-Nielsen Eva , Ciornei Irina , Lafleur Jean-Michel
Published: September 2019

Policies allowing enfranchisement of non-resident citizens (emigrants and their descendants) are now implemented in the majority of states worldwide. A growing number of case studies show that the extension of voting rights to non-resident citizens is often contested among country of origin political parties. However, there is no systematic comparative study of why different political parties support or oppose external voting rights and how this position is framed by the parties. Drawing on a unique data set based on 34 debates across 13 countries, we estimate the extent to which ideology and party family are correlated with the positioning and framing of parties. Among the findings are that the more to the right is a party, the more it tends to support external voting rights, except in the case of radical right parties. The position on emigrant voting rights is largely framed along more pragmatic arguments.
Demography and Dispossession: Explaining the Growth of the Global Informal Workforce, 1950-2000
Authors: Benanav Aaron
Published: September 2019

Since 1950, the world’s urban labor force has expanded dramatically, a process that has been accompanied by a large increase in informal employment. Accounts of these phenomena generally assume that urban workers without formal work are mostly recent migrants from the countryside. This article shows that outside of China, most of the growth of the world’s urban workforce has been the consequence of demographic expansion rather than rural-to-urban migration. A large portion of the world’s growing urban-born workforce has ended up in informal employment. I develop a concept of demographic dispossession to explain the relatively autonomous role demographic growth has played, first, in the proletarianization of the global population and, second, in the informalization of the urban workforce. I then explore the reasons why demographic growth in low- and medium-income countries tended to be more rapid and urban than demographic growth had been historically in the high-income countries.
Database of Families with Twins and Higher Order Multiples in Japanese Twins Mothers Clubs
Authors: Ooki Syuichi
Published: September 2019

It is desirable for twin researchers to be aware of the needs and concerns of families of multiples and provide participants with appropriate and useful feedback and advice based on scientific evidence. Our most recent database on families with twins throughout Japan is based on a questionnaire survey conducted in 2016. Mailed questionnaires, consisting of over 500 items, were used to collect the basic data. The response rate was 38% (566/1478). This is part of a nationwide study designed to assess the long-term effect of perinatal conditions on mothers of multiples. Its aim was to study the growth and development of multiples in childhood, and for the creation of a multifetal mother and child health handbook, and to conduct a genetic epidemiologic study to test the developmental origin of health and disease hypothesis. One of the ultimate aims of this research was to provide evidence-based information on parenting of multiples for families with multiples.
As Artic Sea Ice Disappears, What Happens to Ecosystems?
Authors: Wheeling Kate
Published: September 2019

The northern Bering Sea is experiencing record-setting low winter sea ice levels, which are impacting plankton, fish, and other animals in the region.
Correction: Temporal dynamics of miRNAs in human DLPFC and its association with miRNA dysregulation in schizophrenia
Authors: Hu Zhonghua , Gao Shouguo , Lindberg Daniel , Panja Debabrata , Wakabayashi Yoshi , Li Keshen , Kleinman Joel E. , Zhu Jun , Li Zheng
Published: September 2019

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Scintigraphic Investigations of the Deep and Superficial Lymphatic Systems in the Evaluation of Lower Limb Oedema
Authors: Barbieux Romain , Roman Mirela Mariana , Rivière Fanny , Leduc Olivier , Leduc Albert , Bourgeois Pierre , Provyn Steven
Published: September 2019

The lymphoscintigraphic investigation (LySc) of the superficial lymphatic system (SLS) remains the gold standard for the diagnosis of lower limb lymphoedema. However, LySc of the deep lymphatic system (DLS) may be useful for diagnosing deep lymphatic system insufficiency in patients with lower limb oedema (LLE) but normal and/or paradoxical LySc of the SLS. The purpose of this study was therefore to evaluate a new LySc of the deep lymphatic system in patients presenting with a normal and/or paradoxical SLS exam showing LLE. In all, 15 patients with unilateral and 17 with bilateral LLE underwent 3-phased deep LySc of the lower limb via the injection of 99 mTc-labelled human serum albumin (HSA) nanocolloids in the Kager’s triangle. The absence of popliteal lymphatic node visualization after phase 2 of DLS LySc to diagnose a deep lymphatic insufficiency has a specificity and a sensitivity of 89% in patients with unilateral LLE and without associated venous symptoms. An insufficiency of the DLS was observed in 67% of cases with unilateral LLE and 59% of patients with bilateral LLE of venous and/or lymphatic origin. In conclusion, the lymphoscintigraphic visualization of the popliteal lymphatic nodes after the injection of 99 mTc-labelled HSA nanocolloids in the Kager’s triangle seems to be an effective way to diagnose DLS insufficiency in patients with LLE but normal findings in the SLS.
Mutation profiling of cancer drivers in Brazilian colorectal cancer
Authors: dos Santos Wellington , Sobanski Thais , de Carvalho Ana Carolina , Evangelista Adriane Feijó , Matsushita Marcus , Berardinelli Gustavo Nóriz , de Oliveira Marco Antonio , Reis Rui Manuel , Guimarães Denise Peixoto
Published: September 2019

The molecular basis of colorectal cancer (CRC) can guide patient prognosis and therapy. In Brazil, knowledge on the CRC mutation landscape is limited. Here, we investigated the mutation profile of 150 cancer-related genes by next-generation sequencing and associated with microsatellite instability (MSI) and genetic ancestry in a series of 91 Brazilian CRC patients. Driver mutations were found in the APC (71.4%), TP53 (56.0%), KRAS (52.7%), PIK3CA (15.4%) and FBXW7 (10.9%) genes. Overall, genes in the MAPK/ERK, PIK3/AKT, NOTCH and receptor tyrosine kinase signaling pathways were mutated in 68.0%, 23.1%, 16.5%, and 15.3% of patients, respectively. MSI was found in 13.3% of tumors, most of which were proximal (52.4%, P< 0.001) and had a high mutation burden. European genetic ancestry was predominant (median of 83.1%), followed by Native American (4.1%), Asian (3.4%) and African (3.2%). NF1 and BRAF mutations were associated with African ancestry, while TP53 and PIK3CA mutations were inversely correlated with Native American ancestry. Our study suggests that Brazilian CRC patients exhibit a mutation profile similar to other populations and identify the most frequently mutated genes, which could be useful in future target therapies and molecular cancer screening strategies.
Pioglitazone attenuates kidney injury in an experimental model of gentamicin-induced nephrotoxicity in rats
Authors: Medić Branislava , Stojanović Marko , Rovčanin Branislav , Kekić Dušan , Škodrić Sanja Radojević , Jovanović Gordana Basta , Vujović Katarina Savić , Divac Nevena , Stojanović Radan , Radenković Miroslav , Prostran Milica
Published: September 2019

Gentamicin, belonging to the aminoglycosides, possesses the greatest nephrotoxic effect of all other antibiotics from this group. On the other hand, pioglitazone, which represents peroxisome proliferator-activated receptor γ (PPARγ) agonist recently showed antiinflamatory, antioxidative effects, amelioration of endothelial dysfunction etc. Therefore, the goal of our study was to investigate the effects of pioglitazone on kidney injury in an experimental model of gentamicin-induced nephrotoxicity in rats. These effects were observed by following values of biochemical (serum urea and creatinine) parametars, total histological kidney score, urine level of kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) as well as parametars of oxidative stress (malondialdehyde, superoxide dismutase, catalase, total oxidant status, total antioxidant status, oxidative stress index and advanced oxidation protein products). It seems that pioglitazone protects the injured rat kidney in a U-shaped manner. Medium dose of pioglitazone (1 mg/kg, i.p.) was protective regarding biochemical (serum urea and creatinine), total histological score and the values of kidney injury molecule-1 (KIM-1) (P < 0.05 vs. control group, i.e. rats injected with gentamicin only). This finding could be of great importance for the wider use of aminoglycosides, with therapy that would reduce the occurrence of serious adverse effects, such as nephrotoxicity and acute renal failure.
Prokaryotic soluble overexpression and purification of oncostatin M using a fusion approach and genetically engineered E. coli strains
Authors: Nguyen Minh Tan , Prima Musharrat Jahan , Song Jung-A. , Kim Julee , Do Bich Hang , Yoo Jiwon , Park Sangsu , Jang Jaepyeong , Lee Sunju , Lee Eunyoung , Novais Michelle de Paula , Seo Hyeon-Beom , Lee Seon-yeong , Cho Mi-La , Kim Chong Jai , Jang Yeon Jin , Choe Han
Published: September 2019

Human Oncostatin M (OSM), initially discovered as a tumour inhibitory factor secreted from U-937 cells, is a gp130 (IL-6/LIF) cytokine family member that exhibits pleiotropic effects in inflammation, haematopoiesis, skeletal tissue alteration, liver regeneration, cardiovascular and metabolic diseases. Cytoplasmic expression of OSM inEscherichia coliresults in inclusion bodies, and complex solubilisation, refolding and purification is required to prepare bioactive protein. Herein, eight N-terminal fusion variants of OSM with hexahistidine (His6) tag and seven solubility-enhancing tags, including thioredoxin (Trx), small ubiquitin-related modifier (Sumo), glutathione S-transferase (GST), maltose-binding protein (MBP), N-utilisation substance protein A (Nusa), human protein disulphide isomerase (PDI) and the b‘a’ domain of PDI (PDIb‘a’), were tested for soluble OSM expression inE. coli. The His6-OSM plasmid was also introduced into genetically engineered Origami 2 and SHuffle strains to test expression of the protein. At 18 °C, MBP-tagged OSM was highly expressed and solubility was dramatically enhanced. In addition, His6-OSM was more highly expressed and soluble in Origami 2 and SHuffle strains than in BL21(DE3). MBP-OSM and His6-OSM were purified more than 95% with yields of 11.02 mg and 3.27 mg from a 500 mL culture. Protein identity was confirmed by mass spectroscopy, and bioactivity was demonstrated byin vitroinhibition of Th17 cell differentiation.
Low CYP24A1 mRNA expression and its role in prognosis of breast cancer
Authors: Cai Hongqiao , Jiao Yan , Li Yanqing , Yang Zhaoying , He Miao , Liu Yahui
Published: September 2019

Breast cancer is the most common malignant cancer in women. CYP24A1 expression regulates cellular response to vitamin D, which has antitumor effects against breast cancer. This study aimed to identify the correlation between CYP24A1 mRNA expression and prognosis of breast cancer. This study enrolled 1102 patients, including 1090 females and 12 males, from TCGA-BRCA cohort. The Cancer Genome Atlas database was used to study CYP24A1 mRNA expression in breast cancer, and Chi-squared tests were performed to test the correlation between clinical features and CYP24A1 expression. The prognostic value of CYP24A1 in breast cancer was assessed using Kaplan–Meier curves and Cox analysis. Low CYP24A1 expression was associated with age, molecular subtype, ER, PR, HER2, menopause status, N classification, vital status, overall survial and relapse-free survival. CYP24A1 presented a moderate diagnostic ability in breast cancer. Furthermore, low CYP24A1 expression was correlated with poor prognosis. CYP24A1 was an independent risk factor for breast cancer. CYP24A1 plays an important role in prognosis of breast cancer. CYP24A1 has the potential to be a biomarker, especially in predicting prognosis.
Various modes of action of dietary phytochemicals, sulforaphane and phenethyl isothiocyanate, on pathogenic bacteria
Authors: Nowicki Dariusz , Maciąg-Dorszyńska Monika , Bogucka Krystyna , Szalewska-Pałasz Agnieszka , Herman-Antosiewicz Anna
Published: September 2019

Isothiocyanates (ITCs) derived from cruciferous plants reveal antibacterial activity, although detailed mechanism is not fully elucidated. Recently it has been reported that ITCs induce the stringent response in Escherichia coli strains. The aim of this work was to determine whether two isothiocyanates, sulforaphane (SFN) and phenethyl isothiocyanate (PEITC), similarly as in E. coli induce stringent response in Bacillus subtilis, model Gram(+) bacterium, and test their potency against a panel of clinical isolates belonging to Gram(+) or Gram(−) groups. Minimal inhibitory concentrations were determined as well as effect of ITCs on membranes integrity, synthesis of DNA, RNA and stringent response alarmones was assessed. SFN and PEITC are effective against B. subtilis and bacterial isolates, namely E. coli, K. pneumonia, S. aureus, S. epidermidis and E. faecalis. Interestingly, in B. subtilis and E. faecalis the inhibition of growth and nucleic acids synthesis is independent of ppGpp accumulation. In bacteria, which do not induce the stringent response in the presence of ITCs, membrane integrity disruption is observed. Thus, ITCs are effective against different pathogenic bacteria and act by at least two mechanisms depending on bacteria species.
Emergence of a non-sporulating secondary phenotype in Clostridium (Clostridioides) difficile ribotype 078 isolated from humans and animals
Authors: Connor M. C. , McGrath J. W. , McMullan G. , Marks N. , Guelbenzu M. , Fairley D. J.
Published: September 2019

Clostridium (Clostridioides) difficile is a Gram positive, spore forming anaerobic bacterium that is a leading cause of antibiotic associated diarrhoea in the developed world. C. difficile is a genetically diverse species that can be divided into 8 phylogenetically distinct clades with clade 5 found to be genetically distant from all others. Isolates with the PCR ribotype 078 belong to clade 5, and are often associated with C. difficile infection in both humans and animals. Colonisation of animals and humans by ribotype 078 raises questions about possible zoonotic transmission, and also the diversity of reservoirs for ribotype 078 strains within the environment. One of the key factors which enables C. difficile to be a successful, highly transmissible pathogen is its ability to produce oxygen resistant spores capable of surviving harsh conditions. Here we describe the existence of a non-sporulating variant of C. difficile ribotype 078 harbouring mutations leading to premature stop codons within the master regulator, Spo0A. As sporulation is imperative to the successful transmission of C. difficile this study was undertaken to investigate phenotypic characteristics of this asporogenous phenotype with regards to growth rate, antibiotic susceptibility, toxin production and biofilm formation.
Electrochemical performance of ruthenium nanoparticles decorated on nitride carbon for non-enzymatic detection of hydrogen peroxide
Authors: Cheng Xia , Xu Caili , Chen Qian , Wang Yi , Zhang Yun , Fan Guangyin
Published: September 2019

Ultrafine, ligand-free, and well-distributed Ru NPs on nitride carbon achieved by a facile and straightforward method exhibit superior electrochemical sensing performances for H2O2.
A pyrolysis–phosphorization approach to fabricate carbon nanotubes with embedded CoP nanoparticles for ambient electrosynthesis of ammonia
Authors: Zhang Shengbo , Gong Wanbing , Lv Yang , Wang Haojie , Han Miaomiao , Wang Guozhong , Shi Tongfei , Zhang Haimin
Published: September 2019

The (112) plane dominated CoP nanoparticles in carbon nanotubes (CoP/CNs) fabricated by a pyrolysis-phosphorization approach exhibited superior electrocatalytic NRR activity with a large NH3 yield rate and high faradaic efficiency.
Core–shell hybrid nanowires with Co nanoparticles wrapped in N-doped porous carbon for lightweight microwave absorption
Authors: Zhao Huanqin , Cheng Yan , Zhang Yanan , Zhang Zhu , Zhou Lei , Zhang Baoshan
Published: September 2019

One-dimensional core–shell structured nanowires with Co nanoparticles wrapped in N doped porous carbon were designed as a lightweight, thin and high-performance electromagnetic absorber.
A pan-cancer analysis of progression mechanisms and drug sensitivity in cancer cell lines
Authors: Fleck Julia L. , Pavel Ana B. , Cassandras Christos G.
Published: September 2019

Sequences of genetic events were identified that may help explain common patterns of oncogenesis across 22 tumor types. The general effect of late-stage mutations on drug sensitivity and resistance mechanisms in cancer cell lines was evaluated.
Silver sulfide nanoparticles for photodynamic therapy of human lymphoma cells via disruption of energy metabolism
Authors: Wang Ge , Liu Jing , Zhu Lin , Guo Yuming , Yang Lin
Published: September 2019

Ag2S/BSA hybrid nanoparticles were prepared and studied for their ability to inhibit the growth of human lymphoma cells under light irradiation, via inducing the accumulation of intracellular reactive oxidative species to disrupt energy metabolism.
The photocatalytic degradation of chloramphenicol with electrospun Bi2O2CO3-poly(ethylene oxide) nanofibers: the synthesis of crosslinked polymer, degradation kinetics, mechanism and cytotoxicity
Authors: Xu Qin , Song Zijuan , Ji Shuting , Xu Gang , Shi Wenyan , Shen Longxiang
Published: September 2019

Insoluble poly(ethylene oxide) (PEO) nanofibers were synthesized by adding pentaerythrotol triacrylate (PETA) into precursor solutions prior to electrospinning, and then the obtained fibers were exposed to an electron beam (EB) irradiation.
Iodine doped composite with biomass carbon dots and reduced graphene oxide: a versatile bifunctional electrode for energy storage and oxygen reduction reaction
Authors: Hoang Van Chinh , Dinh Khang Ngoc , Gomes Vincent G.
Published: September 2019

We prepared carbon dots (CDs) via a sustainable, low-cost synthetic route employing eggplant biomass.
A cumulative search for hard X/γ-ray emission associated with fast radio bursts in Fermi/GBM data
Authors: Martone R. , Guidorzi C. , Margutti R. , Nicastro L. , Amati L. , Frontera F. , Marongiu M. , Orlandini M. , Virgilli E.
Published: September 2019

Context. Fast radio bursts (FRBs) are millisecond-long bursts uniquely detected at radio frequencies. FRB 131104 is the only case for which a γ-ray transient positionally and temporally consistent was claimed. This high-energy transient had a duration of ∼400 s and a 15–150 keV fluence Sγ ∼ 4 × 10−6 erg cm−2. However, the association with the FRB is still debated.

Aims. We aim at testing the systematic presence of an associated transient high-energy counterpart throughout a sample of the FRB population.

Methods. We used an approach like that used in machine learning methodologies to accurately model the highly-variable Fermi/GBM instrumental background on a time interval comparable to the duration of the proposed γ-ray counterpart of FRB 131104. A possible γ-ray signal is then constrained considering sample average lightcurves.

Results. We constrain the fluence of the possible γ-ray signal in the 8–1000 keV band down to 6.4 × 10−7 (7.1 × 10−8) erg cm−2 for a 200-s (1-s) integration time. Furthermore, we found the radio-to-gamma fluence ratio to be η >  108 Jy ms erg−1 cm2.

Conclusions. Our fluence limits exclude ∼94% of Fermi/GBM detected long gamma-ray bursts and ∼96% of Fermi/GBM detected short gamma-ray bursts. In addition, our limits on the radio-to-gamma fluence ratio point to a different emission mechanism from that of magnetar giant flares. Finally, we exclude a γ-ray counterpart as fluent as the one possibly associated with FRB 131104 to be a common feature of FRBs.
Study on Parallel Numerical Calculation of Structural Domain Decomposition with Non-Matching Meshes
Authors: Zhang Xiaohu , Sun Qin
Published: September 2019

For the parallel solution of structural finite element problem with non-matching multi-domains, a nonmatched finite element tearing and interconnectiong (FETI) parallel algorithm is proposed based on L-FETI method by introducing the frame node force and modifying the frame displacement compatibility condition and the load balance condition. Based on the radial basis functions (RBF) interpolation technique, the data transfer of internal force and displacement between the neighboring subdomains has a unified matrix format and is easy to program by introducing a local coordinate system into the non-matching interfaces. Taking the finite element model for plate bending problem with four subdomains as an example, two kinds of multi-domains models, matching and non-matching meshes, are constructed respectively. The numerical results show that the out-of-plane deflection of the same nodes on the domain decomposition frame is in a good agreement, which shows that the present method is reasonable and effective for solving the parallel non-matching multi-domains model.
Experimental Study on Influence of Ventilation on Trajectory Characteristics of Free Motion of Supercavitating Vehicle
Authors: Chen Cheng , Yuan Xulong , Ren Yao , Dang Jianjun , Liu Xiyan
Published: September 2019

In order to study the trajectory characteristics of supercavitating vehicle in free motion, a series of experiments were carried out on an unpowered vehicle under ventilation and non-ventilation conditions respectively. High-pressure gas was utilized to launch the vehicle. The flow pattern in free motion was captured by using a high-speed video camera, the variations in the motion parameters and the cavity pressure were simultaneously recorded by using the internal measuring system. The measured data under ventilation and non-ventilation conditions were analyzed in detail, giving the effect of the ventilation on the motion of the vehicle. The experimental results show that the cavitation number fluctuates around a certain value under the influence of both velocity of the vehicle and the ventilation flow rate, keeping the vehicle to stably move in the supercavitating state. Under non-ventilation condition, the vehicle moves stably at the state of supercavitating and double-cavity closed on at the cylindrical section of the vehicle. But the motion turns into instable when the cavity is closed at the shoulder of the vehicle. Therefore, to reduce the cavitation number by ventilation is beneficial to maintaining the stability of the vehicle.
Research of Mobile Underwater Acoustic Communication of M-Ary Combining FDM and Piecewise-LFM
Authors: Li Fulong , Shen Xiaohong , Wang Ling , Wang Haiyan
Published: September 2019

Aiming at the countering doppler shift, a mobile underwater acoustic communication scheme of M-ary via FDM-PLFM is proposed. The cross-correlation between piecewise linear frequency modulation(PLFM) and traditional LFM signal is analyzed based on the cross-correlation function. Combining with frequency division multiplexing(FDM), the spectrum utilization of traditional underwater acoustic LFM communication scheme is improved. With the underwater acoustic LFM communication scheme, the new scheme does not require the doppler frequency shift compensation at the low doppler shift. The simulation results show that the present scheme has lower bit error rate than that for the traditional underwater acoustic M-ary LFM communication method under higher data rate conditions.
Damage Analysis and Experimental Study of Composite Structures with Initial Delamination
Authors: Wang Zhikai , Chen Zhipeng , Yang Nana , Yang Tao
Published: September 2019

Composite laminates are prone to delamination during hot pressing and cooling, this delamination is one of the most important defects that affect the properties of composite structures, the formation and propagation of delamination in composite materials can significantly reduce the structural strength of composite materials and even lead to catastrophic failure. In this paper, the two parameters of the initial stratified position and the initial stratified diameter are selected to research the effects of these two parameters on the mechanical properties of composite laminates through numerical simulation and experiment, and concludes that the influence of initial delamination along the thickness direction on the average compression modulus and strain of the linear segment is small; the influence of delamination on the ultimate bearing capacity increases with the decrease of the distance between the delamination and the center plane. When the diameter of the delamination is in the range of 8%~20% of the effective area(18~44 mm), the influence on the average compression modulus, ultimate bearing capacity and strain of the linear segment is not obvious. When the diameter is increased to 27% of the effective length(60 mm), the above properties have changed greatly. And then, this paper introduces the bilinear controlled cohesive elements into the progressive failure method to calculate the ultimate load capacity of composite laminates, and demonstrate the accuracy of the simulation method by experiments.
Prediction Method and Verification of Fatigue Life for a Turbine Disk with Bolt Hole
Authors: Liu Hongbin , Chen Wei , Liu Lin
Published: September 2019

In order to improve the fatigue life prediction accuracy of FGH96 material for turbine engine at higher stress gradient notch, such as bolt holes, the new mean stress formula is used in this paper, the effect of stress gradient and size effect are considered at the same time, Fatigue test of FGH96 material inter-stage disc simulation test piece is done, and the parameters in the life prediction equation of the model are fitted. Further study on fatigue test of FGH96 material turbine pin bolt hole simulation unit is done, and test results is compared with the forecast results. The result shows that, the improved fatigue life prediction method has higher accuracy, and the validity of the method is proved.
Layout Method of Damping Material for Gearbox Based on Acoustic Contribution
Authors: Liu Yunong , Liu Lan , Liu Geng , Wu Liyan , Liu Chao , Yue Yanjiong
Published: September 2019

In order to realize the low noise design of marine gearbox, a layout method of damping materials for gearbox based on acoustic contribution was proposed. The present method can accurately and effectively determine the additional area of damping materials and achieve greatly the noise reduction effect. Firstly, taking a marine single-stage herringbone gearbox as the object, the finite element/boundary element model for the reducer structure was established. After applying the vibration excitation of the gear system, the radiated noise of each field point was solved. Secondly, by analyzing the acoustic transfer vector (ATV) and modal acoustic contribution (MAC), the surface of the gearbox was partitioned, and the partitioned surface was analyzed by using panel acoustic contribution (PAC). Finally, the damping material was added to the plate area which contributes greatly to the radiated noise, and the effect of the noise reduction under different schemes were compared. The results show that the layout design of damping materials based on the present method can reduce the radiation noise of observation points accurately and effectively in the range of 0~4 000 Hz.
Nonlinear Self-Excited Vibration Mechanism for Under-Actuated Oil-Well Drilling System with Stick-Slip Vibration
Authors: Fu Meng , Li Jianghong , Zhao Aiqi , Wu Yafeng , Chen Zuhao , Zhang Haowei
Published: September 2019

Exploration of oil or gas wells is usually carried out by using drilling system. When the kilometers of drilling system is externally disturbed, the drilling system is prone to undesired stick-slip vibration of the drill-string. The stick-slip vibration of the drill-string belongs to the nonlinear self-excited vibration. In order to study the vibration mechanism, the model for the nonlinear torque on the bit by using Karnopp friction model and the two degrees of freedom model for drilling system were established. The equivalent damping torque formula and the energy variation formula of the drilling system were proposed. The mechanism of the nonlinear self-excited vibration of the drilling system was explained. The simulation results indicated that the stick-slip vibration of the drill-string was caused by the negative value of the equivalent damping force of the drilling system. The equivalent damping torque made the positive work on the system, so that the system absorbed the vibration energy from the outside, which destroyed the stability of the system equilibrium point. The feedback effect in the speed of the drill-bit regulates the system energy to maintain constant vibration without attenuation. In each vibration cycle, the energy input by the system is equal to the energy dissipated by the system. The energy absorbed by the drilling system is mainly converted into the potential energy.
Estimation for Two-Dimensional Incoherently Distributed Source in Double L-Shape Arrays
Authors: Wu Tao , Deng Zhenghong , Xu Jiwei , Gu Qingyue
Published: September 2019

Distributed sources can be regarded as an assembly of point sources within a spatial distribution. In this paper, we explore the estimation of the two-dimensional incoherently distributed sources using double L-shape arrays. The rotational invariance properties of the nominal elevation and nominal elevation are firstly obtained by taking first-order Taylor series expansions with regard to the generalized steering vectors of two pairs of parallel subarrays. The rotation operators can be solved based on signal subspace. Then the nominal elevation and nominal elevation can be obtained from parameters matching method. Estimation of direction of arrival can be used in multi-source scenario and needn't peak-finding search. Lastly the angular spreads can be solved through two-dimensional Capon search based on nominal angles. The simulation experiments show that the proposed method has good performance on the estimation of two-dimensional incoherently distributed sources. Investigating different experimental conditions, sources with different angular spreads, simulations are conducted to validate better estimation accuracy of the proposed method.
Morphological Control and Simulation of Fractal Growth
Authors: Zhou Min , Zhang Haili , Wang Yihao , Bao Xiaolan
Published: September 2019

The idea and method of control are introduced into the fractal theory from the perspective of quantitative analysis. In order to speed up aggregation, MDLA growth model with source items is put froward by altering the way of particle generating and killing of the standard DLA growth model. The effect of the iterative step size and particle radius on the growth morphology are discussed, and the growth morphology was simulated directionally.
Study of non-invasive instruments for the measurement of pulsed X-ray high voltage tube
Authors: Agazar Mohamed , Perrillat Denis , Saadeddine Hanane , Robert Christophe , Casteignau Laurence , Fortune Dominique
Published: September 2019

Non-invasive instruments (kVp meters) are widely used in radiology with diagnostic and guidance systems. Placed in the x-ray beam, they combine detectors and filters, to determine X-ray tube voltage and exposure time, which are the most important quantities in radiology and diagnostic quality control. Calibration of these instruments were limited by reference bench capabilities. General Electric Medical System France and LNE (The national metrology institute in France) have developed a reference bench for the characterization of kVp meters. The set up includes a fast high voltage generator associated with its internal measuring systems and an X-ray tube. The measurements are compared with an invasive reference standard. The set-up is installed in a Faraday cage, precautions have been taken in order to carry out accurate measurements and special adaptations have been made to avoid stray capacitances, which affect the dynamic performance of the generator. Results have shown a good agreement with the internal measuring system of the generator but the kVp meters have shown both good and bad results depending the exposure time, the current and the positioning.
Deep learning and 3D optical metrology improve complex feature detection and ranking
Authors: Calvez Anne
Published: September 2019

With the increasing need of measurement automation in many industrial sectors, 3D optical metrology is now required to integrate options like surface feature detection and classification that were previously performed by visual inspectors. The recent combination of deep learning algorithms with 3D optical metrology improves characterization and classification of complex surfaces.
Metrology for biomethane conformity assessment: measure trace gas impurities in biomethane
Authors: Li Jianrong , Persijn Stefan , de Krom Iris , Meuzelaar Heleen , van der Veen Adriaan M.H.
Published: September 2019

To facilitate the use of biomethane in existing transmission and distribution infrastructures, CEN/TC 408 developed specifications (EN 16723) for injecting biomethane into the natural gas grids and using it as a transport fuel. Currently, the test methods cited in EN 16723 lack metrological aspects and have not been specifically developed for biomethane. To address this need, ISO/TC193/SC1/WG25 “Biomethane” has been created to work on standardized methods. To assess conformity of biomethane with the specification and to provide essential input to WG25, test methods are being developed in this research for a group of impurities such as siloxanes, halogenated volatile organic compounds, hydrogen chloride, hydrogen fluoride. A further objective of this research is to develop fit-for-purpose measurement standards for these parameters, to enable SI-traceable calibration and facilitate accurate measurement results. An overview of the progress made with respect to the development of measurement standards and test methods for trace level concentrations of impurities is presented, with a focus on static measurement standards of siloxanes and halogenated volatile organic compounds, dynamic gas standards of HCl and HF, as well as corresponding test methods based on gas chromatography and spectroscopic techniques. The work presented is pivotal for the development of metrological infrastructure for biomethane conformity assessment.
Calibration of articulating arm coordinate measuring machines per ASME B89.4.22-2004
Authors: Johnson Dain
Published: September 2019

Solving issues in testing articulated arm coordinate measuring machines by bringing homogeneity to the process was the intention of the standard but it also had the consequence of being difficult to comply with in 100% totality. Accessibility to appropriate testing standards, whether financially or in their inherent stability can prove very difficult for a commercial calibration laboratory. Through hours of design & build and with deep testing resources, Trescal has created a platform from which AACMM with effective diameters up to 10.5 ft can be tested for touch measurement, and ISO17025 accredited, with full compliance to the B89 standard.
Risk and opportunity management: an approach for the mechanical testing field
Authors: Jamal-Eddine Abdul-Karim
Published: September 2019

Risk and opportunity management is a rising topic in the mechanical testing field. The importance of this issue was recently reflected in the newest version of ISO 17025 which emphasized requirements for risk assessment and opportunity taking. This article investigates the most important elements regarding the topic of risk and opportunity management in an environmental testing lab, considering a real case study of the “L2EC” laboratory. Taking the multiple areas of experimental work (climatic, vibration, mechanical, etc...), the study covers multiple areas of management and quality through a comprehensive quantitative framework. Elements of risk and uncertainty control, project planning, decision making and opportunity management are eventually translated into an applicable and coherent general road plan that fulfils and integrates well in the daily framework and strategy of the laboratory.
Evaluate and quantify the drift of a measuring instrument
Authors: Pou Jean-Michel , Leblond Laurent
Published: September 2019

The question of drift in measuring instruments is an essential one in metrology. Calibration establishes the "metrological state" of the instrument on the date it is carried out, but what does it tell us about tomorrow, a month from now, or at the end of the calibration validity period? If, with certain instrumentation (in particular "fixed" instruments, for instance "physical" standards and limit gauges) the situation is relatively straightforward, it is not so simple with instruments that take measurements. The FD X 07-014[1] booklet, moreover, distinguishes between the two types of device, those where drift can be observed (since calibration uncertainties tend to be minor, which is generally true of size standards) and the others (measuring instruments). This article deals with the specific case of measuring.
Humidity Calibration Automation
Authors: FENOTTI Fulvio , VASTY David
Published: September 2019

This article describes an automated humidity calibration system developed in Trescal Italy using a software developed internally, a high resolution Digital Single-Lens Reflex (DSLR) camera, climatic chambers and chilled mirror hygrometers as reference standards.
Quantifying the effect of thermal heat radiation emitted by the walls of a climatic chamber on temperature measurements
Authors: Favreau Jacques-Olivier. , Bories Sarah. , Salem Marzougui. , Georgin Eric.
Published: September 2019

The study consists in quantifying the effect of the thermal radiation of the climatic chamber walls on air temperature measurements for contact thermometry. Air temperature measurements are affected by surface interactions with the environment, such as those of the thermometer and walls (surface condition, emissivity and air velocity). The walls of the enclosure are generally made of stainless steel, a potentially radiating material. To characterize the effect of the walls, we have varied environmental conditions such as the emissivity of the walls of the chamber and the sensors, the surface of the sensors, temperature and illumination. These different configurations allow us to deduce their impacts on the temperature measurements. To quantify this effect we simulated different configurations to isolate the radiation effect. Two surface states are tested: low emissivity metal surface and painted surface with matte black paint of high emissivity. This study highlights the effect of the walls on the air temperature measurements in the center of the climatic chamber. The experimental results were also subject to a theoretical verification using the equation of the standard ISO 7726 [1]. The quantification of the effect of radiation from the walls of the climate chamber on temperature measurements becomes significant from 100 °C. Quantification of thermal radiation is 0.4 °C at 100 °C and 0.8 °C at 150 °C.
Comprendre et surveiller la portée d’accréditation grâce à l’ISO 9001
Authors: Bozonnet Didier , Chevaucher Hafsa
Published: September 2019

As it is said in ILAC G18 requirements, accredited laboratories according to ISO 15189 or ISO 17025 should describe and manage their scope of accreditation. Whether its description is quite understood and well conducted, the management of the scope, even if there are written procedures, is much fuzzier, especially the audit of the scope or its potential redesign. In 2018, ISO 17025 has been revised and allowed now laboratories to supervise and monitor their system of management according to ISO 9001. The main benefit of this is to increase efficiency thanks to these two concepts: the risk-based and the process-based approaches. The chapter 8.3 of ISO 9001 in particular can also help: “Design and development of products and services”. Moreover, at the time of writing, a new project ISO 15189 is in progress and there is every reason to believe that this new version will embrace ISO 17025 scheme for the system of management. The aim of this publication is to mix the “scope management” requirements with those of ISO 9001 and monitor the scope of accreditation as a full-fledged process and more, include it in the process mapping; this will help laboratories to supervise their scope of accreditation with more serenity.
Wireless calibration for Industry 4.0
Authors: Benitez Roberto , Benitez Roberto
Published: September 2019

During the 1980´s, before the industrial globalization took place, some recommended practices or standards were used to provide the calibration services for inspection, measurement and testing equipment (IM&TE) in America. Before the ISO Standards were used to provide quality services or to be ISO accredited, the calibration laboratories were using the MIL-STD-45662A. While the ISO standards became the most applicable references for quality systems certification and for the accreditation of the calibration laboratories the ISO/IEC-17025 became the standard that should be met for the accreditation. Since the beginning of the calibration services, the calibration certificates contained information about the status of the instrument, depending of its type and the method used to calibrate the instrument, also some other requirements were included in the certificates, like the uncertainty and the evidence of the proficiency tests that the laboratory had to provide. With the technological advancement in electronics, the instruments became more sophisticated and accurate. The use of computers and dedicated software for calibration developed new calibration methods. Industry 4.0 includes a wide variety of sensors to monitor different parameters along the process or to measure quality specifications, most of those sensors are electronically integrated to the process control. Metrology 4.0 is giving a new way of calibration services applying the AI and IoT.
Spastic Diplegia in a Haitian Girl with Angelman Syndrome
Authors: Latchman Kumarie , Nieto-Moreno Margarita , Alberola Roberto Lopez
Published: September 2019

Spastic diplegia, a muscle hypertonia motor syndrome, can occur in conjunction with the characteristic abnormal movement features of Angelman syndrome (AS), a neurodevelopmental disorder with primary features of ataxic gait, happy demeanor, developmental delay, speech impairment, intellectual disability, microcephaly, and seizures. Spastic diplegia is classically associated with cerebral palsy (CP), an umbrella term encompassing developmental delay, abnormal brain magnetic resonance imaging findings, and various types of CP including spastic, ataxic, dyskinetic, and mixed types. We present a 12-year-old Haitian patient of African descent with AS due to a microdeletion involving the entire UBE3A (ubiquitin-protein ligase E3A) gene and spastic diplegia. She was initially given a clinical diagnosis of CP. Cases of AS in patients of African descent have been rarely reported and this case of severe spastic diplegia, unresponsive to medical intervention, reflects a rarely reported presentation of AS in patients of African descent and possibly the first reported case of a Haitian patient with this clinical presentation. Given that deletions are the most common mechanism resulting in AS, this case report provides supportive evidence that chromosome 15q11 deletion-type AS is most frequently associated with spastic diplegia, a more severe motor impairment phenotype in AS.
Geriatric Patients with Free Flap Reconstruction: A Comparative Clinical Analysis of 256 Cases
Authors: Wähmann Matthias , Wähmann Melodie , Henn Dominic , Xiong Lingyun , Hirche Christoph , Harhaus Leila , Kneser Ulrich , Kremer Thomas
Published: September 2019

Background In elderly patients, complex soft tissue defects are increasingly observed due to the prolonged life expectancy and accompanying comorbidities. The aim of this study is to evaluate whether free tissue transfer is safe in very old patients without additional risk and complications.

Methods All patients older than 65 years undergoing free tissue transfer between November 2007 and September 2016 were reviewed in a retrospective study. Two cohorts were compared regarding perioperative morbidity and postoperative outcome (cohort 1 [old patients, ages 65–79]; cohort 2 [very old patients, ages ≥ 80]).

Results In total, 256 patients were included in the study (cohort 1 [n = 217]; cohort 2 [n = 39]). Overall, 262 free flaps were performed due to a second microsurgical reconstruction in six cases. No statistically significant differences between cohorts were observed regarding surgical complications, total flap losses, and mortality. Detailed evaluation of cohort 2 revealed a significant learning curve during the observation period regarding the perioperative management and procedure of soft tissue reconstruction: operation length as well as postoperative intensive care unit stay decreased significantly over time (p < 0.05) and also surgical complications showed a positive trend (p = 0.07). We ascertained a shift toward a “more reliable” flap selection from predominantly anterolateral thigh flap) to axial flaps such as rectus abdominis and latissimus dorsi flaps.

Conclusion Our study showed that age is not associated with an increased risk of postoperative complications. Reliable muscle free flaps, two-stage procedures, and safe vascular supply are important strategic aspects to achieve microvascular tissue transfer with high success rates in geriatric patients.
Visualizing the melting processes in ultrashort intense laser triggered gold mesh with high energy electron radiography
Authors: Zhou Zheng , Fang Yu , Chen Han , Wu Yipeng , Du Yingchao , Zhang Zimin , Zhao Yongtao , Li Ming , Tang Chuanxiang , Huang Wenhui
Published: September 2019

High-energy electron radiography (HEER) is a promising diagnostic tool for high-energy-density physics, as an alternative to tools such as X/γ-ray shadowgraphy and high-energy proton radiography. Impressive progress has been made in the development and application of HEER in the past few years, and its potential for high-resolution imaging of static opaque objects has been proved. In this study, by taking advantage of the short pulse duration and tunable time structure of high-energy electron probes, time-resolved imaging measurements of high-energy-density gold irradiated by ultrashort intense laser pulses are performed. Phenomena at different time scales from picoseconds to microseconds are observed, thus proving the feasibility of this technique for imaging of static and dynamic objects.
Billiard systems change character of dynamics with different billiard ball radius
Authors: Bandari Anashe
Published: September 2019

A new study shows increasing the radius of a ball can change the dynamics of a billiard system between regular dynamics to chaos and back.