bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of a high-pressure screw compressor performances
Authors: Eparu C N , Neacșa A , Prundurel A P , Rădulescu R , Slujitoru C , Toma N , Nițulescu M 
Published: September 2019

Abstract
Oil flooded screw compressors with discharge pressures of up to 26 bar have been available, commercially for some years. However, demands for higher pressure operation led to the design, construction and testing of a compressor operating with discharge pressures of up to 45 bar. To maximize the compressor efficiency, extensive performance simulations were carried out. Since 1980 oil flooded screw compressors have been used in many process gas compression applications and in the last year the higher pressure and larger capacity was realized. From 2010 to 2015 INCDT COMOTI manufactured screw compressors under GHH-Rand license (CU type, with max. delivery pressure 26 bar). Experience gain in this process gives us the power to develop the new type of screw compressors - based on license - with high delivery pressure - max. 45 bar. This paper will present details about the tests with a new high pressure screw compressor test in a closed loop test configuration. The machine was then tested in a closed loop test rig and, as is shown, the measured performance agrees well with that predicted by the numerical model. The parameters will be analysed starting from CFD modelling of the process and finally comparative analysis with actual parameters. The demonstrated advantages of this type of compressor, like high reliability, simple foundations, low operational cost, low initial cost, suitability for process fluctuation - gas pressure, gas composition - led to a significant demand for such compressors.
Analysis of a proportional pressure regulator
Authors: Avram M , Ștefănescu M-F , Șerban A , Dobrovicescu A , Grămescu B 
Published: September 2019

Abstract
The paper deals with the theoretical and experimental analysis of a proportional pneumatic device. Such a piece of equipment can be integrated in the structure of an intelligent system that works with compressed gases. Different constructive variants of this type of equipment are analyzed. Authors focus their attention on a device that makes use of an electro-mechanic actuator operating with a proportional electromagnet. For the mathematical model some simplifying assumptions are identified. The mathematical model is numerically integrated. The behavior of the proportional pneumatic device at the variation of the inlet pressure and outlet mass flow rate consumption is pointed out.
Effect of yaw angle on the global performances of Horizontal Axis Wind Turbine - QBlade simulation
Authors: Husaru D E , Bârsănescu P D , Zahariea D 
Published: September 2019

Abstract
The yaw angle has a great importance in the wind turbine working. Even though most of the large turbines have yaw mechanisms, they do not have an instant response. The aerodynamic forces and torque on the blades fluctuate, depending on the yaw angle. The design and the numerical simulation of the wind turbine were performed with the Blade Element Momentum method in open source QBlade software. The power coefficient, torque, thrust and power output generated by wind turbine in non-yawed flow were analysed. The simulations have been performed for non-yawed flow, in rotational speed range between 2100 and 3300 rpm and wind velocity of 15 m/s. Simulations for yaw angle range have been performed between ± 60°, with 5° step at rated rotational speed of 2700 rpm. The results are presented through charts for global parameters in both non-yawed flow, and yawed flow. The effect of yaw angle on global performances of the wind turbines is more important after the value of 25° when the power output decrease with about 15% from power output in non-yawed flow. The average value of the exponent from conventional relation of power coefficient in yawed flow is 1.77 in good concordance with experimental tests.
Modelling and simulation of a hydraulic system used for wind turbines
Authors: Pelin R-I , Tița I 
Published: September 2019

Abstract
For wind turbines, pitch control is essential. In some cases, especially in the case of large scale wind turbines, hydraulic control is used. In this paper a hydraulic system used in wind turbine pitch control is analysed. Modelling and simulation of hydraulic systems is necessary in order to acknowledge the drawbacks and advantages before starting the design of the system. By acknowledging, the differences between the model of a physical system and a system in a virtual environment, one can handle the improvement, in terms of price or time-consumption. Considering the proposed diagram of the pitch control hydraulic system, it is presented the block diagram created in MATLAB Simscape Fluids. Some results of the simulation are presented. There are included conclusions and plans for future work.
SCUBA-2 observations of candidate starbursting protoclusters selected by Planck and Herschel-SPIRE
Authors: Cheng T , Clements D L , Greenslade J , Cairns J , Andreani P , Bremer M , Conversi L , Cooray A , Dannerbauer H , De Zotti G , Eales S , González-Nuevo J , Ibar E , Leeuw L , Ma J , Michałowski M J , Nayyeri H , Riechers D A , Scott D , Temi P , Vaccari M , Valtchanov I , van Kampen E , Wang L 
Published: September 2019

ABSTRACT
We present SCUBA-2 850 $\mathrm{ \mu}$m observations of 13 candidate starbursting protoclusters selected using Planck and Herschel data. The cumulative number counts of the 850 $\mathrm{ \mu}$m sources in 9 of 13 of these candidate protoclusters show significant overdensities compared to the field, with the probability &lt;10−2 assuming the sources are randomly distributed in the sky. Using the 250, 350, 500, and 850 $\mathrm{ \mu}$m flux densities, we estimate the photometric redshifts of individual SCUBA-2 sources by fitting spectral energy distribution templates with an MCMC method. The photometric redshift distribution, peaking at 2 &lt; z &lt; 3, is consistent with that of known z &gt; 2 protoclusters and the peak of the cosmic star formation rate density (SFRD). We find that the 850 $\mathrm{ \mu}$m sources in our candidate protoclusters have infrared luminosities of $L_{\mathrm{IR}}\gtrsim 10^{12}\, \mathrm{L}_{\odot }$ and star formation rates of SFR = (500–1500) M⊙ yr−1. By comparing with results in the literature considering only Herschel photometry, we conclude that our 13 candidate protoclusters can be categorized into four groups: six of them being high-redshift starbursting protoclusters, one being a lower redshift cluster or protocluster, three being protoclusters that contain lensed dusty star-forming galaxies or are rich in 850 $\mathrm{ \mu}$m sources, and three regions without significant Herschel or SCUBA-2 source overdensities. The total SFRs of the candidate protoclusters are found to be comparable or higher than those of known protoclusters, suggesting our sample contains some of the most extreme protocluster population. We infer that cross-matching Planck and Herschel data is a robust method for selecting candidate protoclusters with overdensities of 850 $\mathrm{ \mu}$m sources.
On the mass segregation of cores and stars
Authors: Alcock Hayley L , Parker Richard J 
Published: September 2019

ABSTRACT
Observations of pre- and proto-stellar cores in young star-forming regions show them to be mass segregated, i.e. the most massive cores are centrally concentrated, whereas pre-main-sequence stars in the same star-forming regions (and older regions) are not. We test whether this apparent contradiction can be explained by the massive cores fragmenting into stars of much lower mass, thereby washing out any signature of mass segregation in pre-main-sequence stars. Whilst our fragmentation model can reproduce the stellar initial mass function, we find that the resultant distribution of pre-main sequence stars is mass segregated to an even higher degree than that of the cores, because massive cores still produce massive stars if the number of fragments is reasonably low (between one and five). We therefore suggest that the reason cores are observed to be mass segregated and stars are not is likely due to dynamical evolution of the stars, which can move significant distances in star-forming regions after their formation.
Can redshift errors bias measurements of the Hubble Constant?
Authors: Davis Tamara M , Hinton Samuel R , Howlett Cullan , Calcino Josh 
Published: September 2019

ABSTRACT
Redshifts have been so easy to measure for so long that we tend to neglect the fact that they too have uncertainties and are susceptible to systematic error. As we strive to measure cosmological parameters to better than 1 per cent it is worth reviewing the accuracy of our redshift measurements. Surprisingly small systematic redshift errors, as low as 10−4, can have a significant impact on the cosmological parameters we infer, such as H0. Here, we investigate an extensive (but not exhaustive) list of ways in which redshift estimation can go systematically astray. We review common theoretical errors, such as adding redshifts instead of multiplying by (1 + z); using v = cz; and using only cosmological redshift in the estimates of luminosity and angular diameter distances. We consider potential observational errors, such as rest wavelength precision, air to vacuum conversion, and spectrograph wavelength calibration. Finally, we explore physical effects, such as peculiar velocity corrections, galaxy internal velocities, gravitational redshifts, and overcorrecting within a bulk flow. We conclude that it would be quite easy for small systematic redshift errors to have infiltrated our data and be impacting our cosmological results. While it is unlikely that these errors are large enough to resolve the current H0 tension, it remains possible, and redshift accuracy may become a limiting factor in near future experiments. With the enormous efforts going into calibrating the vertical axis of our plots (standard candles, rulers, clocks, and sirens) we argue that it is now worth paying a little more attention to the horizontal axis (redshifts).
Heavy negative ion growth in Titan’s polar winter
Authors: Wellbrock A , Coates A J , Jones G H , Vuitton V , Lavvas P , Desai R T , Waite J H 
Published: September 2019

ABSTRACT
A significant but unexpected result of the Cassini mission was the discovery of heavy organic negative ions in Titan’s ionosphere at altitudes between about 950 and 1400 km by the CAPS Electron Spectrometer (ELS). The heaviest ions were observed during the T16 fly-by with masses over 13 000 u/q. This is significantly higher than the maximum masses observed during other fly-bys. We study T16 CAPS-ELS observations and examine the evolution of mass spectra at different altitudes. We also study maximum mass trends using a large data set from all available CAPS-ELS observations of the Cassini mission in order to investigate the conditions necessary to allow negative ions to grow to the highest masses. For the first time, we are able to investigate the relationship between the highest mass particles and seasonal effects. We find that the combination of high latitude and winter conditions, resulting in long-term restricted solar flux, create an environment in which ion growth can reach the highest masses, as observed during T16. Restricting solar flux long term, and hence photodestruction reactions such as photodetachment, appears to be essential for negative ions to grow beyond 10 000 u/q.
A solution of Jupiter’s gravitational field from Juno data with the orbit14 software
Authors: Serra Daniele , Lari Giacomo , Tommei Giacomo , Durante Daniele , Gomez Casajus Luis , Notaro Virginia , Zannoni Marco , Iess Luciano , Tortora Paolo , Bolton Scott J 
Published: September 2019

ABSTRACTThe latest estimation of Jupiter’s gravitational field was obtained by processing the Doppler data from two gravity orbits of NASA’s Juno mission, using the Jet Propulsion Laboratory software monte. In this work, we present the results of the analysis of the same measurements employing the orbit determination software orbit14, developed at the University of Pisa, used here for the first time with real data. We found that the estimated values of Jupiter’s spherical harmonic coefficients from the two solutions are consistent within the formal uncertainty. The analysis is complemented with a discussion on the results obtained with alternative set-ups.
ALMACAL – VI. Molecular gas mass density across cosmic time via a blind search for intervening molecular absorbers
Authors: Klitsch Anne , Péroux Céline , Zwaan Martin A , Smail Ian , Nelson Dylan , Popping Gergö , Chen Chian-Chou , Diemer Benedikt , Ivison R J , Allison James R , Muller Sébastien , Swinbank A Mark , Hamanowicz Aleksandra , Biggs Andrew D , Dutta Rajeshwari 
Published: September 2019

ABSTRACT
We are just starting to understand the physical processes driving the dramatic change in cosmic star formation rate between z ∼ 2 and the present day. A quantity directly linked to star formation is the molecular gas density, which should be measured through independent methods to explore variations due to cosmic variance and systematic uncertainties. We use intervening CO absorption lines in the spectra of mm-bright background sources to provide a census of the molecular gas mass density of the Universe. The data used in this work are taken from ALMACAL, a wide and deep survey utilizing the ALMA calibrator archive. While we report multiple Galactic absorption lines and one intrinsic absorber, no extragalactic intervening molecular absorbers are detected. However, due to the large redshift path surveyed (Δz = 182), we provide constraints on the molecular column density distribution function beyond z ∼ 0. In addition, we probe column densities of N(H2) > 1016 atoms cm−2, 5 orders of magnitude lower than in previous studies. We use the cosmological hydrodynamical simulation IllustrisTNG to show that our upper limits of $\rho ({\rm H}_2)\lesssim 10^{8.3}\, \text{M}_{\odot }\, \text{Mpc}^{-3}$ at 0 < z ≤ 1.7 already provide new constraints on current theoretical predictions of the cold molecular phase of the gas. These results are in agreement with recent CO emission-line surveys and are complementary to those studies. The combined constraints indicate that the present decrease of the cosmic star formation rate history is consistent with an increasing depletion of molecular gas in galaxies compared to z ∼ 2.
A Novel Robotic-Assisted Technique to Implant the Responsive Neurostimulation System
Authors: Tran Diem Kieu , Paff Michelle , Mnatsakanyan Lilit , Sen-Gupta Indranil , Lin Jack J , Hsu Frank P K , Vadera Sumeet 
Published: September 2019

Abstract

BACKGROUND
The responsive neurostimulation system (RNS) (NeuroPace Inc, Mountain View, California) was approved as an adjunctive therapy for medically refractory focal epilepsy. RNS detects epileptiform patterns and delivers electrical stimulation to abort seizures.

OBJECTIVE
To describe a novel technique of RNS lead implantation using robotic-assisted targeting of ictal-onset zones based on stereoelectroencephalography (sEEG) localization. Secondary objectives are to report the accuracy of robotic-assisted lead implantation using the ROSA robot as well as to report the clinical outcome achieved after RNS implantation by this method.

METHODS
A total of 16 patients with medically refractory focal epilepsy underwent sEEG implantation for ictal-onset localization followed by robotic RNS implantation. The electrode most correlative with ictal onset on sEEG was chosen as the target for the RNS electrode. Seizure control was measured at 6-mo and 1-yr follow-up. Ictal-onset electrocorticography (ECoG) data from RNS were compared with ictal onset from sEEG leads based on calculations of lead target to actual lead location from the ROSA robot.

RESULTS
At 6-mo follow-up, the average percent seizure reduction was 82% based upon self-reported seizure diaries. At 1-yr follow-up, 8 patients had an average of 90% seizure reduction. The location of seizure onset from ECoG data show similar onset from sEEG leads within 0.165-mm discrepancy.

CONCLUSION
The ROSA robot provides an ideal method for targeting subcortical ictal-onset zones. This method of RNS lead implantation achieves high accuracy and is associated with favorable clinical outcomes.
Microsurgical Anatomy of the Meningeal Branch of the Dorsolateral Medullary Plexus
Authors: Tayebi Meybodi Ali , Zhao Xiaochun , Borba Moreira Leandro , Preul Mark C , Alhilali Lea M , Lawton Michael T 
Published: September 2019

Abstract

BACKGROUND
Meningeal branches originating from intradural arteries may be involved in several diseases such as meningeal tumors and arteriovenous lesions. These “pial-dural” arterial connections have been described for anterior cerebral, posterior cerebral, and cerebellar arteries. However, to the best of our knowledge, meningeal supply originating from the arterial plexus over the dorsolateral aspect of the medulla oblongata (dorsolateral medullary plexus [DLMP]) has not been described.

OBJECTIVE
To define the microsurgical anatomy of the meningeal branch of DLMP.

METHODS
A total of 20 cadaver heads (40 sides) underwent far-lateral craniotomy and the cerebellomedullary cisterns were explored to find the DLMP and any meningeal branches. Additionally, de-identified intraoperative images of 85 patients with vertebral artery (VA)/posterior inferior cerebellar artery aneurysms who had undergone far-lateral craniotomy were studied to find any meningeal branches of DLMP.

RESULTS
The meningeal branches of DLMP were identified in 4 cadavers/sides. These branches reached the region of jugular tubercle (JT) after crossing the accessory nerve. In 3 specimens, these branches were joined by a small twig from V4-VA before penetrating the dura. DLMP meningeal branches were found in 12 patients of the studied cohort (14%) with similar anatomical features as those found in the cadaveric study.

CONCLUSION
DLMP may give rise to meningeal branches to the adjacent dura of JT. The actual prevalence of this anatomic variation is difficult to estimate using our data. However, when present, these branches may have important clinical implications, ie, diseases such as dural arteriovenous fistulas, pial arteriovenous malformations (AVMs), and meningeal-based tumors.
Vascular Endothelial Growth Factor A Signaling Promotes Spinal Central Sensitization and Pain-related Behaviors in Female Rats with Bone Cancer
Authors: Hu Xue-Ming , Yang Wei , Du Li-Xia , Cui Wen-Qiang , Mi Wen-Li , Mao-Ying Qi-Liang , Chu Yu-Xia , Wang Yan-Qing 
Published: September 2019

Abstract

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What This Article Tells Us That Is New

Background
Cancer pain is a pervasive clinical symptom impairing life quality. Vascular endothelial growth factor A has been well studied in tumor angiogenesis and is recognized as a therapeutic target for anti-cancer treatment. This study tested the hypothesis that vascular endothelial growth factor A and vascular endothelial growth factor receptor 2 contribute to bone cancer pain regulation associated with spinal central sensitization.

Methods
This study was performed on female rats using a metastatic breast cancer bone pain model. Nociceptive behaviors were evaluated by mechanical allodynia, thermal hyperalgesia, spontaneous pain, and CatWalk gait analysis. Expression levels were measured by real-time quantitative polymerase chain reaction, western blot, and immunofluorescence analysis. Excitatory synaptic transmission was detected by whole-cell patch-clamp recordings. The primary outcome was the effect of pharmacologic intervention of spinal vascular endothelial growth factor A/vascular endothelial growth factor receptor 2–signaling on bone cancer pain behaviors.

Results
The mRNA and protein expression of vascular endothelial growth factor A and vascular endothelial growth factor receptor 2 were upregulated in tumor-bearing rats. Spinal blocking vascular endothelial growth factor A or vascular endothelial growth factor receptor 2 significantly attenuated tumor-induced mechanical allodynia (mean ± SD: vascular endothelial growth factor A, 7.6 ± 2.6 g vs. 5.3 ± 3.3 g; vascular endothelial growth factor receptor 2, 7.8 ± 3.0 g vs. 5.2 ± 3.4 g; n = 6; P < 0.0001) and thermal hyperalgesia (mean ± SD: vascular endothelial growth factor A, 9.0 ± 2.4 s vs. 7.4 ± 2.7 s; vascular endothelial growth factor receptor 2, 9.3 ± 2.5 s vs. 7.5 ± 3.1 s; n = 6; P < 0.0001), as well as spontaneous pain and abnormal gaits. Exogenous vascular endothelial growth factor A enhanced excitatory synaptic transmission in a vascular endothelial growth factor receptor 2–dependent manner, and spinal injection of exogenous vascular endothelial growth factor A was sufficient to cause pain hypersensitivity via vascular endothelial growth factor receptor 2–mediated activation of protein kinase C and Src family kinase in naïve rats. Moreover, spinal blocking vascular endothelial growth factor A/vascular endothelial growth factor receptor 2 pathways suppressed protein kinase C-mediated N-methyl-d-aspartate receptor activation and Src family kinase-mediated proinflammatory cytokine production.

Conclusions
Vascular endothelial growth factor A/vascular endothelial growth factor receptor 2 contributes to central sensitization and bone cancer pain via activation of neuronal protein kinase C and microglial Src family kinase pathways in the spinal cord.
Prediction of Unilateral Meniere’s Disease Attack Using Inner Ear Test Battery
Authors: Wu Po-Hsuan , Chang Chih-Ming , Lo Wu-Chia , Wang Chi-Te , Wen Ming-Hsun , Huang Tsung-Wei , Young Yi-Ho , Cheng Po-Wen 
Published: September 2019

Objectives:
In the clinical setting, a variety of inner ear test results are obtained from patients with unilateral Meniere’s disease (MD). In this study, the authors use inner ear test results as parameters to illustrate the relationship between inner ear function and vertigo attack frequency.

Design:
We retrospectively enrolled 50 unilateral MD patients. In addition to clinical symptoms, the results of pure-tone audiometry and caloric, acoustic cervical vestibular-evoked myogenic potential (cVEMP), galvanic cVEMP, vibratory ocular VEMP (oVEMP), and galvanic oVEMP tests were collected via chart review. The multiple linear regression method was used to examine which independent variables have a statistically significant influence on vertigo attacks.

Results:
In affected ears, the abnormal rate of the caloric, acoustic cVEMP, galvanic cVEMP, vibratory oVEMP, and galvanic oVEMP tests was 74%, 76%, 48%, 34%, and 30%, respectively. According to the regression model, the abnormal galvanic cVEMP response and abnormal galvanic oVEMP response had significantly negative correlations with the frequency of vertigo attacks after logarithmic transformation. A predictive model for disease attack frequency using significant parameters and their regression coefficients was proposed:

JOURNAL/earher/04.03/00003446-202005000-00014/inline-graphic1/v/2023-07-26T063803Z/r/image-tiff

Conclusions:
Using the proposed model with galvanic VEMP, clinicians could develop better strategies to manage vertigo attacks in patients with MD.