bluuebunny/crossref_metadata_2025_split huggingface dataset:
Caught in broad daylight: Topographic constraints of zooplankton depth distributions
Authors: Aarflot Johanna M. , Aksnes Dag L. , Opdal Anders F. , Skjoldal Hein Rune , Fiksen Øyvind 
Published: November 2018

AbstractFor visual predators, sufficient light is critical for prey detection and capture. Because light decays exponentially with depth in aquatic systems, vertical movement has become a widespread strategy among zooplankton for avoiding visual predation. However, topographical features such as seamounts have been shown to block their descent, trapping them in illuminated waters with potential feeding benefits for visually searching fish. Here, we present an extensive and previously unpublished dataset on the vertical distribution of zooplankton in the topographically rugged Barents Sea, a continental shelf region hosting some of the largest fish stocks in the world. By modeling the ambient light exposure of zooplankton in relation to the bathymetry, we find support for a similar blockage mechanism. During daytime, zooplankton are exposed to four orders of magnitude more light above shallow banks than in the deeper water surrounding the banks. We show that zooplankton depth distributions are highly related to zooplankton size and that the bottom constrains the vertical distributions. Consequently, zooplankton remain in the planktivores’ visual feeding habitat over the banks but not in deeper areas. Bottom topography and light absorbance are significant determinants of the seascape ecology across continental shelves with heterogeneous bathymetry.
In situ Study Unravels Bio‐Nanomechanical Behavior in a Magnetic Bacterial Nano‐cellulose (MBNC) Hydrogel for Neuro‐Endovascular Reconstruction
Authors: Pavón Juan Jose , Allain Jean Paul , Verma Devendra , Echeverry‐Rendón Mónica , Cooper Christy L. , Reece Lisa M. , Shetty Akshath R. , Tomar Vikas 
Published: November 2018

AbstractSurgical clipping and endovascular coiling are well recognized as conventional treatments of Penetrating Brain Injury aneurysms. These clinical approaches show partial success, but often result in thrombus formation and the rupture of aneurysm near arterial walls. The authors address these challenging brain traumas with a unique combination of a highly biocompatible biopolymer hydrogel rendered magnetic in a flexible and resilient membrane coating integrated to a scaffold stent platform at the aneurysm neck orifice, which enhances the revascularization modality. This work focuses on the in situ diagnosis of nano‐mechanical behavior of bacterial nanocellulose (BNC) membranes in an aqueous environment used as tissue reconstruction substrates for cerebral aneurysmal neck defects. Nano‐mechanical evaluation, performed using instrumented nano‐indentation, shows with very low normal loads between 0.01 to 0.5 mN, in the presence of deionized water. Mechanical testing and characterization reveals that the nano‐scale response of BNC behaves similar to blood vessel walls with a very low Young´s modulus, E (0.0025 to 0.04 GPa), and an evident creep effect (26.01 ± 3.85 nm s−1). These results confirm a novel multi‐functional membrane using BNC and rendered magnetic with local adhesion of iron‐oxide magnetic nanoparticles.
MRI‐guided laser interstitial thermal thalamotomy for medically intractable tremor disorders
Authors: Harris Meghan , Steele John , Williams Rebecca , Pinkston Jim , Zweig Richard , Wilden Jessica Anne 
Published: November 2018

ABSTRACTIntroductionMedically intractable tremors are a common, difficult clinical situation. Deep brain stimulation decreases Parkinson's disease resting tremor and essential tremor, but not all patients are candidates from a diagnostic, medical, or social standpoint, prompting the need for alternative surgical strategies.MethodsWe describe 13 patients with medically intractable tremor treated with laser interstitial thermal thalamotomy performed under general anesthesia using live MRI‐guidance and the Clearpoint stereotactic system.ResultsAll patients had a dramatic decrease in tremor immediately postoperatively, which has been sustained through follow‐up (3‐17 months) in all but 1 patient (mean tremor score reduction of 62%; 10.33 ± 2.69 to 3.89 ± 3.1). Objective side effects were transient and included imbalance and paresthesia.ConclusionMedically intractable tremor treated with laser interstitial thermal thalamotomy may be a useful addition to the treatment armamentarium for medically intractable tremor disorders. © 2018 International Parkinson and Movement Disorder Society
Compound heterozygous mutations in CFTR causing CBAVD in Chinese pedigrees
Authors: Yang Bin , Wang Xi , Zhang Wei , Li Hongjun , Wang Binbin 
Published: November 2018

AbstractBackgroundCongenital bilateral absence of the vas deferens (CBAVD) is an important cause of obstructive azoospermia and male infertility. Mutations of CFTR caused the majority of CBAVD cases, and ADGRG2 was recently identified as a new pathogenic gene. Yet, most of the genetic evidence came from sporadic cases, and only one mutation in CFTR can be found in patients.MethodsIn present study, we collected two CBAVD pedigrees, each having two affected male siblings. We performed whole exome sequencing on all patients and validated all potential variants by Sanger sequencing.ResultsWe excluded ADGRG2 variants but identified compound heterozygous variants of CFTR in both families (NM_000492.3:c.1210‐33_1210‐6GT[13]T[5] and c.4056G>C;p.Gln1352Cys in pedigree 1, c.592G>C;p.Ala198Pro and c.3717G>A;p.Arg1239= in pedigree 2), which were subsequently validated by direct sequencing. c.1210‐33_1210‐6GT[13]T[5] (also known as IVS8‐T5‐TG13) was a known disease‐causing variant causing the skipping of exon 9 of CFTR and inherited from the proband's mother. p.Gln1352Cys and Ala198Pro were rare or novel in public databases and predicted to be deleterious. The p.Arg1239= was a synonymous variant but located at the end of an exon, which was predicted to alter the splicing pattern.ConclusionOur study, in which compound heterozygous variants were identified in two pedigrees, provides more familial evidence that only recessive variants (homozygous or compound heterozygous) in CFTR cause CBAVD. Furthermore, whole exome sequencing may be utilized as a useful tool for mutation screening of genes causing CBAVD.
The 3D isodose structure‐based method for clinical dose distributions comparison in pretreatment patient‐QA
Authors: Tamborra Pasquale , Martinucci Erica , Massafra Raffaella , Bettiol Marco , Capomolla Caterina , Zagari Annarita , Didonna Vittorio 
Published: November 2018

IntroductionBefore the approval of any Intensity Modulated Radiation Therapy or Volumetric Modulated Arc Therapy treatment plan, quality assurance (QA) tests are needed to reveal potential errors such as an inaccurate calculation of the dose distribution, the failure of the record‐and‐verify system, or the delivery system of the linear accelerator. Currently, the method adopted to compare the measured dose distribution with the treatment planning system TPS calculated dose distribution is gamma analysis. However, gamma analysis has been shown to be ineffective for the clinical evaluation of treatment plans. We proposed and tested a new method (the isodose structures method) alternative to gamma analysis.MethodDifferent errors were introduced in 33 error‐free Head and Neck plans. The modified plans were recalculated using TPS software and the dose distributions obtained were compared to those of the original (error‐free) plans. The comparison was performed using gamma analysis and the new method. The target was to calculate overall and organ‐specific gamma passing rates as well as the overlapping ratio (OR) and volume ratio (VR) factors of the isodose structures method for each error‐included plan.ResultsEight of the 33 plans passed both the gamma analysis and the isodose structures (IS) analysis, ten plans did not pass either of them, while 13 plans which did not pass the IS analysis, passed the gamma analysis. Two plans which did not pass gamma, passed IS analysis. Furthermore, Dose Volume Histogram (DVH) metrics could not detect the low agreement between the dose distributions of two error‐free plans and the respective modified plans. In this case, the IS analysis also allowed us to detect clinically meaningful differences between measured and TPS dose distributions.ConclusionsThe IS method analysis clearly showed a high efficiency in detecting clinically relevant differences between TPS and measured dose distributions not seen in gamma analysis and in DVH‐based metrics. Therefore, IS analysis proved to be a valid tool, alternative to gamma analysis for dose comparison in patient‐specific QA test.
Free‐breathing, non‐ECG, continuous myocardial T1 mapping with cardiovascular magnetic resonance multitasking
Authors: Shaw Jaime L. , Yang Qi , Zhou Zhengwei , Deng Zixin , Nguyen Christopher , Li Debiao , Christodoulou Anthony G. 
Published: November 2018

PurposeTo evaluate the accuracy and repeatability of a free‐breathing, non‐electrocardiogram (ECG), continuous myocardial T1 and extracellular volume (ECV) mapping technique adapted from the Multitasking framework.MethodsThe Multitasking framework is adapted to quantify both myocardial native T1 and ECV with a free‐breathing, non‐ECG, continuous acquisition T1 mapping method. We acquire interleaved high–spatial resolution image data and high–temporal resolution auxiliary data following inversion‐recovery pulses at set intervals and perform low‐rank tensor imaging to reconstruct images at 344 inversion times, 20 cardiac phases, and 6 respiratory phases. The accuracy and repeatability of Multitasking T1 mapping in generating native T1 and ECV maps are compared with conventional techniques in a phantom, a simulation, 12 healthy subjects, and 10 acute myocardial infarction patients.ResultsIn phantoms, Multitasking T1 mapping correlated strongly with the gold‐standard spin‐echo inversion recovery (R2 = 0.99). A simulation study demonstrated that Multitasking T1 mapping has similar myocardial sharpness to the fully sampled ground truth. In vivo native T1 and ECV values from Multitasking T1 mapping agree well with conventional MOLLI values and show good repeatability for native T1 and ECV mapping for 60 seconds, 30 seconds, or 15 seconds of data. Multitasking native T1 and ECV in myocardial infarction patients correlate positively with values from MOLLI.ConclusionMultitasking T1 mapping can quantify native T1 and ECV in the myocardium with free‐breathing, non‐ECG, continuous scans with good image quality and good repeatability in vivo in healthy subjects, and correlation with MOLLI T1 and ECV in acute myocardial infarction patients.
Simultaneous multi‐slice cardiac cine with Fourier‐encoded self‐calibration at 7 Tesla
Authors: Rapacchi Stanislas , Troalen Thomas , Bentatou Zakarya , Quemeneur Morgane , Guye Maxime , Bernard Monique , Jacquier Alexis , Kober Frank 
Published: November 2018

PurposeTo accelerate cardiac cine at 7 tesla using simultaneous multi‐slice (SMS) acquisition with self‐calibration to resolve misalignment between calibration and imaging data due to breathing motion.MethodsA spoiled‐gradient echo cine sequence was modified with radiofrequency phase‐cycled SMS excitations. A Fourier encoding strategy was applied along the cardiac phase dimension to allow for slice untangling and split‐slice GRAPPA calibration. Split‐slice GRAPPA was coupled with regular GRAPPA (SMS‐GRAPPA) and L1‐SPIRiT (SMS‐L1SPIRiT) for image reconstruction. 3‐slice SMS cine MRI was evaluated in ten subjects against single‐slice cine MRI in terms of SNR and contrast‐to‐noise ratio and slice leakage.ResultsSNR decreased significantly from 10.1 ± 7.1 for single‐slice cine to 7.4 ± 2.8 for SMS‐GRAPPA (P = 0.02) and was recovered to 9.0 ± 4.5 with SMS‐L1SPIRiT (P = 0.02). Contrast to noise ratio decreased significantly from 14.5 ± 8.1 for single‐slice cine to 5.6 ± 3.6 for SMS‐GRAPPA (P < 0.0001) and increased slightly but significantly back to 6.7 ± 4.4 for SMS‐L1SPIRiT (P = 0.03). Specific absorption rate restrictions imposed a reduced nominal flip angle (−37 ± 7%, P = 0.02) for 3‐slice SMS excitations compared to single‐slice acquisitions. SMS slice leakage increased significantly from apex (8.6 ± 6.5 %) to base (13.1 ± 4.1 %, P = 0.03) in the left ventricle.ConclusionThree‐fold acceleration of cine at 7T was achieved using the proposed SMS technique. Fourier encoding self‐calibration and regularized image reconstruction enabled simultaneous acquisition of three slices without significant SNR decrease but significant CNR decrease linked to the reduced nominal excitation flip angle.
Long non‐coding RNAs influence the transcriptome in pulmonary arterial hypertension: the role of PAXIP1‐AS1
Authors: Jandl Katharina , Thekkekara Puthenparampil Helene , Marsh Leigh M , Hoffmann Julia , Wilhelm Jochen , Veith Christine , Sinn Katharina , Klepetko Walter , Olschewski Horst , Olschewski Andrea , Brock Matthias , Kwapiszewska Grazyna 
Published: November 2018

AbstractIn idiopathic pulmonary arterial hypertension (IPAH), global transcriptional changes induce a smooth muscle cell phenotype characterised by excessive proliferation, migration, and apoptosis resistance. Long non‐coding RNAs (lncRNAs) are key regulators of cellular function. Using a compartment‐specific transcriptional profiling approach, we sought to investigate the link between transcriptional reprogramming by lncRNAs and the maladaptive smooth muscle cell phenotype in IPAH. Transcriptional profiling of small remodelled arteries from 18 IPAH patients and 17 controls revealed global perturbations in metabolic, neuronal, proliferative, and immunological processes. We demonstrated an IPAH‐specific lncRNA expression profile and identified the lncRNA PAXIP1‐AS1 as highly abundant. Comparative transcriptomic analysis and functional assays revealed an intrinsic role for PAXIP1‐AS1 in orchestrating the hyperproliferative and migratory actions of IPAH smooth muscle cells. Further, we showed that PAXIP1‐AS1 mechanistically interferes with the focal adhesion axis via regulation of expression and phosphorylation of its downstream target paxillin. Overall, we show that changes in the lncRNA transcriptome contribute to the disease‐specific transcriptional landscape in IPAH. Our results suggest that lncRNAs, such as PAXIP1‐AS1, can modulate smooth muscle cell function by affecting multiple IPAH‐specific transcriptional programmes. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
Dynamic Monte Carlo simulations of competition in crystallization of mixed polymers grafted on a substrate
Authors: Nie Yijing , Liu Yong , Liu Rongjuan , Zhou Zhiping , Hao Tongfan 
Published: November 2018

ABSTRACTNowadays, preparation of poly(lactide) (PLA) with high content of stereocomplex crystallites (SCs) is receiving more and more attentions. The stereocomplex formation between enantiomeric poly(l‐lactide) and poly(d‐lactide) can efficiently improve the corresponding mechanical properties and thermal stability. In the current work, using dynamic Monte Carlo simulations, the microscopic mechanism of SC formation in grafted polymers was investigated. The increase in grafting density can lead to the enhancement of SC formation. On one hand, the miscibility between the chains of different types can be improved due to the grafting. On the other hand, the increase in grafting density can result in the higher degree of chain extension and the change in crystal nucleation and growth modes. The changes facilitate the stereocomplex formation. These findings not only provide an effective way to prepare PLAs with high content of SCs, but also reveal the underlying mechanisms controlling the SC formation. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 89–97
Monte Carlo calculation of the mass stopping power of EBT3 and EBT‐XD films for protons for energy ranges of 50–400 MeV
Authors: Shi Chengyu , Chen Chin‐Cheng , Mah Dennis , Chan Maria F. 
Published: November 2018

AbstractObjectiveThe goal of the present study was to calculate the continuous slowing down approximation (CDSA) ranges and derive mass stopping power for EBT3 and EBT‐XD films for therapeutic protons energy ranges of 50–400 MeV.MethodsThe MCNPX and TRansport of Ions in Matter (TRIM) Monte Carlo codes were used in this study. Utilizing the published International Commission on Radiation Units and Measurement 49 data for the water mass stopping power and CSDA ranges, the mass stopping powers of EBT3 and EBT‐XD films were derived using the approximation proposed by Newhauser and Zhang in 2009.ResultsThe calculated CSDA ranges by MCNPX and TRIM in water were first benchmarked to International Commission on Radiation Units and Measurement 49 published data for water, and found to be within 1% with a 1.4‐mm maximum difference. The calculated CSDA values in EBT3 film, compared with the measured CSDA ranges in the EBT3 film, were within 2% of the calculated values with a 3‐mm maximum difference. The MCNPX and TRIM results for CSDA ranges agreed with each other to within 2.7% for EBT3 film and 4.4% for EBT‐XD film. The overall uncertainties of the MCNPX and TRIM‐derived CSDA ranges were 3% and 1.3%, respectively.ConclusionThe mass stopping powers for Gafchromic EBT3 and EBT‐XD films were derived.
Orthogonal second‐order space‐filling designs with insights from simulation experiments to support test planning
Authors: Sanchez Paul J. , Sanchez Susan M. 
Published: November 2018

AbstractFrequency‐based designs are presented for exploring large numbers of factors in simulation experiments. This approach yields completely orthogonal full second‐order space‐filling designs. We describe how they are generated, explore their space‐filling properties, and compare their performance to other designs of similar sizes. We illustrate their use for test planning on a simulation model of a live counter‐IED (improved explosive device) test event and present some ideas about ways in which simulation experiments can be used to support planning for live tests.
Forecasting value‐at‐risk in oil prices in the presence of volatility shifts
Authors: Ewing Bradley T. , Malik Farooq , Anjum Hassan 
Published: November 2018

AbstractRecent evidence suggests shifts (structural breaks) in the volatility of returns causes non‐normality by significantly increasing kurtosis. In this paper, we endogenously detect significant shifts in the volatility of oil prices and incorporate this information to estimate Value‐at‐Risk (VaR) to accurately forecast large declines in oil prices. Our out‐of‐sample performance results indicate that the model, which incorporates both time varying volatility (without making any distributional assumptions) and shifts in volatility, produces more accurate VaR forecasts than several benchmark methods. We make a timely contribution as the recent more frequent occurrences of unexpected large oil price declines has gained significant attention because of its substantial impact on the financial markets and the global economy.
Beyond equidistant sampling for performance and cost: A loop‐shaping approach applied to a motion system
Authors: van Zundert Jurgen , Oomen Tom 
Published: November 2018

SummaryNonequidistant sampling potentially enhances the performance/cost trade‐off that is present in traditional equidistant sampling schemes. The aim of this paper is to develop a systematic feedback control design approach for systems that go beyond equidistant sampling. A loop‐shaping design framework for such nonequidistantly sampled systems is developed that addresses both stability and performance. The framework only requires frequency response function measurements of the LTI system, whereas it appropriately addresses the linear periodically time‐varying behavior introduced by the nonequidistant sampling. Experimental validation on a motion system demonstrates the superiority of the design framework for nonequidistantly sampled systems compared to traditional designs that rely on equidistant sampling.
Multivariable supertwisting fixed‐time approach for RLV re‐entry attitude control
Authors: You Ming , Zong Qun , Zuo Linxuan , Wang Xiao , Zhao Xinyi 
Published: November 2018

SummaryThe attitude control problem of reusable launch vehicles (RLVs) is investigated based on multivariable supertwisting fixed‐time comprehensive control strategy. A novel multivariable supertwisting fixed‐time approach, which can guarantee that the states converge to zero within a fixed time, is proposed. According to the multiple time scale principle, the RLV attitude control system is divided into attitude angle subsystem and attitude angle rate subsystem. Based on multivariable supertwisting fixed‐time approach, comprehensive design of fixed‐time disturbance observer and controller is proposed to ensure that the attitude angle tracking error converges to zero within a fixed time. The features of the proposed control scheme contain that the settling time is independent of initial conditions and it has the better property of chattering reduction. Finally, the efficiency of the proposed method is verified through numerical simulation.
Recent Progress on Electrocatalyst and Photocatalyst Design for Nitrogen Reduction
Authors: Li Mengqiao , Huang Hao , Low Jingxiang , Gao Chao , Long Ran , Xiong Yujie 
Published: November 2018

AbstractAmmonia is one of the most important chemicals due to its enormous applications in fertilizer production and as an energy carrier. The production of ammonia mainly relies on the traditional Haber–Bosch process under high temperature and pressure, leading to massive energy consumption and notable environmental issues. Recently, electrocatalytic and photocatalytic nitrogen (N2) fixation have emerged for achieving green production of ammonia owing to their features of environmental friendliness and cost‐effectiveness. However, ammonia production through electrocatalysis and photocatalysis is still far away from practical applications. To facilitate the practical applications, a thorough understanding of nitrogen fixation is highly desired for the future design of high‐efficiency catalysts. Here, the fundamental investigations on electrocatalytic and photocatalytic N2 reduction are summarized. Based on the fundamental understanding, the current approaches and design strategies for heterogeneous catalysts toward electrocatalytic and photocatalytic N2 reduction are then presented. Finally, the remaining challenges and future opportunities in this field are outlined, leveraging the existing understanding on structure–property relationships. It is anticipated that this review sheds some light on the development of advanced catalytic systems for ammonia production through N2 fixation.
Silver‐coated monolithic silica column for separation of trans fatty acids
Authors: Poškus Vilius , Vičkačkaitė Vida 
Published: November 2018

AbstractA monolithic silica sorbent has been successfully synthesized and modified with aminopropyl groups. The modification was achieved by the reaction of (3‐aminopropyl)triethoxysilane and silanol groups on the sorbent surface. For the formation of silver nanoparticles on the aminopropyl groups modified monolithic sorbent, silver nitrate was used as a precursor and formaldehyde as a reducing reagent. Prepared sorbent was tested for pre‐separation of trans fatty acids methyl esters followed by gas chromatography analysis. Due to the interaction between the silver nanoparticles on sorbent surface and double bounds of fatty acids methyl esters, fractionation based on a number of double bounds and on the configuration was achieved.