bluuebunny/crossref_metadata_2025 huggingface dataset:
Constraining the nature of the possible extrasolar PDS110b ring system
Authors: Pinheiro Tiago F. L. L. , Sfair Rafael
Published: July 2021

The young star PDS110 in the Ori OB1a association underwent two similar eclipses in 2008 and 2011, each of which lasted for a period of at least 25 days. One plausible explanation for these events is that the star was eclipsed by an unseen giant planet (named PDS110b) circled by a ring system that fills a large fraction of its Hill sphere. Through thousands of numerical simulations of the three-body problem, we constrain the mass and eccentricity of this planet as well the size and inclination of its ring, parameters that are not well determined by the observational data alone. We carried out a broad range of different configurations for the PDS110b ring system and ruled out all that did not match with the observations. The result shows that the ring system could be prograde or retrograde; the preferred solution is that the ring has an inclination lower than 60° and a radius between 0.1 and 0.2 au and that the planet is more massive than 35 MJup and has a low eccentricity (<0.05).
An internal heating mechanism operating in ultra-short-period planets orbiting magnetically active stars
Authors: Lanza A. F.
Published: July 2021

Context. Rocky planets with orbital periods shorter than ~1 day have been discovered by the method of transits and their study can provide information on Earth-like planets not available from bodies on longer period orbits.

Aims. A new mechanism for the internal heating of such ultra-short-period planets is proposed based on the gravitational perturbation produced by a non-axisymmetric quadrupole moment of their host stars. Such a quadrupole is due to the magnetic flux tubes in the stellar convection zone, unevenly distributed in longitude and persisting for many stellar rotations as observed in young late-type stars.

Methods. The rotation period of the host star evolves from its shortest value on the zero-age main sequence (ZAMS) to longer periods due to the loss of angular momentum through a magnetized wind. If the stellar rotation period comes close to twice the orbital period of the planet, the quadrupole leads to a spin-orbit resonance that excites oscillations of the star-planet separation. As a consequence, a strong tidal dissipation is produced inside the planet that converts the energy of the oscillations into internal heat. The total heat released inside the planet scales as a−8, where a is the orbit semimajor axis, and it is largely independent of the details of the planetary internal dissipation or the lifetime of the stellar magnetic flux tubes.

Results. We illustrate the operation of the mechanism by modeling the evolution of the stellar rotation and of the innermost planetary orbit under the action of the stellar wind and the tides in the cases of CoRoT-7, Kepler-78, and K2-141 whose present orbital periods range between 0.28 and 0.85 days. If the spin-orbit resonance occurs, the maximum power dissipated inside the planets ranges between 1018 and 1019 W, while the total dissipated energy is on the order of 1030−1032 J over a time interval as short as (1−4.5) × 104 yr.

Conclusions. Our illustrative models suggest that, if their host stars started their evolution on the ZAMS as fast rotators with periods between 0.5 and 1.0 days, the resonance occurred after about 40 Myr since the host stars settled on the ZAMS in all the three cases. This huge heating over such a short time interval produces a complete melting of the planetary interiors and may shut off their hydromagnetic dynamos. These may initiate a successive phase of intense internal heating owing to unipolar magnetic star-planet interactions and affect the composition and the escape of their atmospheres, producing effects that could be observable during the entire lifetime of the planets.
Evolution of the local spiral structure of the Milky Way revealed by open clusters
Authors: Hao C. J. , Xu Y. , Hou L. G. , Bian S. B. , Li J. J. , Wu Z. Y. , He Z. H. , Li Y. J. , Liu D. J.
Published: July 2021

The structure and evolution of the spiral arms of our Milky Way are basic but long-standing questions in astronomy. In particular, the lifetime of spiral arms is still a puzzle and has not been well constrained from observations. In this work, we aim to inspect these issues using a large catalogue of open clusters. We compiled a catalogue of 3794 open clusters based on Gaia EDR3. A majority of these clusters have accurately determined parallaxes, proper motions, and radial velocities. The age parameters for these open clusters are collected from references or calculated in this work. In order to understand the nearby spiral structure and its evolution, we analysed the distributions, kinematic properties, vertical distributions, and regressed properties of subsamples of open clusters. We find evidence that the nearby spiral arms are compatible with a long-lived spiral pattern and might have remained approximately stable for the past 80 million years. In particular, the Local Arm, where our Sun is currently located, is also suggested to be long-lived in nature and probably a major arm segment of the Milky Way. The evolutionary characteristics of nearby spiral arms show that the dynamic spiral mechanism might be not prevalent for our Galaxy. Instead, density wave theory is more consistent with the observational properties of open clusters.
The eROSITA Final Equatorial-Depth Survey (eFEDS)
Authors: Schneider P. C. , Freund S. , Czesla S. , Robrade J. , Salvato M. , Schmitt J. H. M. M.
Published: July 2021

Stars are ubiquitous X-ray emitters and will be a substantial fraction of the X-ray sources detected in the on-going all-sky survey performed by the eROSITA instrument aboard the Spectrum Roentgen Gamma (SRG) observatory. We use the X-ray sources in the eROSITA Final Equatorial-Depth Survey (eFEDS) field observed during the SRG performance verification phase to investigate different strategies to identify the stars among other source categories. We focus here on Support Vector Machine (SVM) and Bayesian approaches, and our approaches are based on a cross-match with theGaiacatalog, which will eventually contain counterparts to virtually all stellar eROSITA sources. We estimate that 2060 stars are among the eFEDS sources based on the geometric match distance distribution, and we identify the 2060 most likely stellar sources with the SVM and Bayesian methods, the latter being named HamStars in the eROSITA context. Both methods reach completeness and reliability percentages of almost 90%, and the agreement between both methods is, incidentally, also about 90%. Knowing the true number of stellar sources allowed us to derive association probabilitiespijfor the SVM method similar to the Bayesian method so that one can construct samples with defined completeness and reliability properties using appropriate cuts inpij. The thus identified stellar sources show the typical characteristics known for magnetically active stars, specifically, they are generally compatible with the saturation level, show a large spread in activity for stars of spectral F to G, and have comparatively high fractional X-ray luminosities for later spectral types.
A homogeneous relaxation low mach number model
Authors: Faccanoni Gloria , Grec Bérénice , Penel Yohan
Published: July 2021

In the present paper, we investigate a new homogeneous relaxation model describing the behaviour of a two-phase fluid flow in a low Mach number regime, which can be obtained as a low Mach number approximation of the well-known HRM. For this specific model, we derive an equation of state to describe the thermodynamics of the two-phase fluid. We prove some theoretical properties satisfied by the solutions of the model, and provide a well-balanced scheme. To go further, we investigate the instantaneous relaxation regime, and prove the formal convergence of this model towards the low Mach number approximation of the well-known HEM. An asymptotic-preserving scheme is introduced to allow numerical simulations of the coupling between spatial regions with different relaxation characteristic times.
L’acte d’écriture chez Joyce
Authors: Safouan Moustapha
Published: July 2021

Pour Joyce, la raclée qu’il a eu de ses camarades n’est pas un événement, il a « laissé tomber le corps comme une pelure ». Son image inconsciente du corps n’y est pas. Ce qui fait dire à Lacan que l’imaginaire n’est pas noué au réel et à l’inconscient chez Joyce. Mais alors, comment le corps à la lettre ? La réponse de Lacan se trouve dans les fameuses épiphanies de Joyce, qui, comme le dit à sa façon Moustapha Safouan, permettent un nouage entre le réel et l’inconscient.
Begutachtung des Restless-legs-Syndroms
Authors: Happe Svenja , Kotterba Sylvia , Heidbreder Anna , Kallweit Ulf , Mayer Geert , Benes Heike , Hornyak Magdolna
Published: July 2021

Das Restless-legs-Syndrom (RLS) ist eine der häufigsten neurologischen Erkrankungen. Gutachterliche Fragestellungen bei RLS-Patienten nehmen seit den vergangenen Jahren stetig zu. Daher hat die AG Motorik und Schlaf der Deutschen Gesellschaft für Schlafforschung und Schlafmedizin (DGSM) 2006 erstmals Empfehlungen zur Begutachtung und sozialmedizinischen Einschätzung des RLS erarbeitet. Im Folgenden werden die spezifischen Empfehlungen zur Beurteilung des RLS im Rahmen gutachterlicher Verfahren in einer Neubearbeitung vorgestellt. Diese Empfehlungen stellen eine Grundlage zur Vereinheitlichung und Qualitätssicherung in der Begutachtung des RLS dar, sie sollen jedoch nicht in die individuelle Freiheit und Verantwortung des jeweils beauftragten Gutachters eingreifen. Da bisher keine evidenzbasierten Studien über das RLS vorliegen, die die Besonderheiten der gutachterlichen Situation berücksichtigen, sind diese Empfehlungen als Konsensusdokument konzipiert.
Differenzialdiagnostik und Therapie von Hypersomnolenz-Erkrankungen
Authors: Mevers Claudia , Kallweit Ulf
Published: July 2021

Tagesschläfrigkeit stellt ein häufiges und die Leistungsfähigkeit und Lebensqualität einschränkendes Symptom dar. Die Ursachen für Tagesschläfrigkeit (EDS) sind vielfältig und beinhalten zentralnervöse Erkrankungen mit Hypersomnolenz wie die Narkolepsie oder idiopathische Hypersomnie. Eine Differenzierung von Tagesmüdigkeit, EDS und Hypersomnie stellt eine wichtige Grundlage für eine erfolgreiche Diagnosestellung und somit der weiteren Behandlung dar. Die Diagnostik erfolgt im Wesentlichen klinisch-anamnestisch sowie durch schlafmedizinische Untersuchungen. Narkolepsie ist eine seltene (auto-)immunvermittelte neurologische Erkrankung und geht u. a. mit einer schweren Störung von Wachheit und Schlaf einher. Die Behandlung beinhaltet verhaltenstherapeutische Maßnahmen und eine symptomatische medikamentöse Behandlung.
Zirkadiane Schlaf-Wach-Rhythmusstörungen
Authors: Rodenbeck Andrea
Published: July 2021

Zirkadiane Schlaf-Wach-Rhythmusstörungen beruhen auf einer Diskrepanz zwischen der individuellen intrinsischen Schlaf-Wach-Rhythmik und dem äußeren Hell-Dunkel-Wechsel bzw. den gegebenen sozialen Anforderungen. Dabei ist die zeitliche Verteilung des Schlafens und Wachens innerhalb des 24-Stunden-Tages verändert, der Schlaf selbst ist ungestört und erholsam, sofern die Betroffenen ihrer intrinsischen Schlaf-Wach-Rhythmik folgen können. Es bestehen transiente, extern bedingte (Schichtarbeitsstörung, Jetlag) und chronisch-intrinsische Störungen innerhalb dieser Diagnosegruppe. Von hoher klinischer Relevanz sind das unregelmäßige Schlaf-Wach-Muster bei demenziellen Syndromen, die freilaufende Schlaf-Wach-Rhythmik bei Blinden, die verzögerte Schlafphase bei Jugendlichen und die Schichtarbeitsstörung. Eine frühzeitige adäquate Diagnostik mittels Schlaf-Wach-Tagebuch und Aktigrafie über mindestens 14 Tage hilft, jahrelange Fehldiagnosen zu vermeiden und ggf. Chronifizierungen zu verhindern. Therapeutisch kommen bei den chronischen Formen vor allem melatonerge Substanzen und Lichttherapie sowie multimodale Ansätze in Betracht.
Opticopathy Caused by Endoprosthesis-Related Cobalt Intoxication
Authors: Bodenbender Jan-Philipp , Schubert Florian , Paul Christoph
Published: July 2021

Cobalt intoxication is a rare cause of toxic opticopathy, and may be caused by metal endoprostheses. Since its clinical appearance is unspecific and the incidence low, diagnosis is challenging. Due to the dramatic consequences of delayed treatment, cobalt intoxication should be considered as a rare differential diagnosis of bilateral loss of vision in patients with appropriate history.
Verwendung differenzierter Beatmungsstrategien in der präklinischen Notfallmedizin in der Bundesrepublik Deutschland
Authors: Jansen Gerrit , Kappelhoff Nils , Scholz Sean , Rehberg Sebastian , Borgstedt Rainer
Published: July 2021

Ziel der Studie Die vorliegende Arbeit untersucht den präklinischen Einsatz differenzierter Beatmungsstrategien in Deutschland.

Methodik Onlinebefragung deutscher Notärzte nach Verfügbarkeit moderner Respiratoren, regelhaft verwendeten Beatmungseinstellungen, Monitoring und Zielparametern der Ventilation.

Ergebnisse Die Verfügbarkeit moderner Notfallrespiratoren betrug 95%. Regelhafte Abweichungen von den Leitlinien zur Beatmung wurden von 68% angegeben und betrafen positiven
endexspiratorischer Druck (19%), Tidalvolumen (13%), Spitzendruck (3%) Atemfrequenz (2%). 90% verwendeten regelmäßig die Kapnografie. 82% steuerten den inspiratorischen Sauerstoffgehalt
anhand der Sauerstoffsättigung. Eine Inverse-Ratio-Ventilation wurde regelmäßig von 9% verwendet.

Schlussfolgerung Abweichungen von leitliniengerechten Beatmungseinstellungen und -Monitoring sind häufig. Die aus der Intensivmedizin stammenden Empfehlungen sollten präklinisch auf
Anwendbarkeit evaluiert und ggf. adaptiert werden.
Frühdiagnose des Pankreaskarzinoms – Die Rolle von Endosonografie und Sonografie
Authors: Schorr Friedrich , Essig Manfred Walter
Published: July 2021

Pankreaskarzinome sind im Vergleich zu anderen Tumorarten relativ selten, die Prognose ist aber weiterhin schlecht, da die Tumoren meist in einem fortgeschrittenen Stadium diagnostiziert werden. Eine Frühdiagnostik wäre für das Überleben sinnvoll, ein generelles Screening ist für die Allgemeinbevölkerung aufgrund der niedrigen Prävalenz nicht möglich. Ein Screening ist nur für spezielle Risikogruppen mit einem hohen/erhöhten Karzinomrisiko (Keimbahnmutationen, familiäres Pankreaskarzinom, muzinöse zystische Pankreastumoren) etabliert. Weitere Risikokonstellationen (Pankreatitis, Diabetes mellitus, Zigaretten- und Alkoholabusus) sollten jedoch beachtet werden, um frühe Neoplasien nicht zu übersehen. Bedeutung kommt insbesondere der transabdominellen Ultraschalluntersuchung als weit verbreitetem erstem Untersuchungsverfahren zu. Damit können bereits erste Verdachtsmomente mit hoher Sensitivität beschrieben und der Tumorverdacht kann durch Einsatz von Ultraschallkontrastmittel erhärtet werden. Die Endosonografie hat in der weiteren Diagnostik eine herausragende Bedeutung. Durch zusätzliche Verfahren mit Einsatz von Ultraschallkontrastmittel, Elastografie und Feinnadelpunktion ist in der Regel eine definitive Klärung mit hoher Sensitivität und Spezifität möglich mit dem Ziel, die bislang schlechte Prognose des Pankreaskarzinoms weiter zu verbessern.
Multi-Class UHPLC-MS/MS Method for Plant Toxins and Cyanotoxins in Food Supplements and Application for Belgian Market Samples
Authors: Van Pamel Els , Henrottin Jean , Van Poucke Christof , Gillard Nathalie , Daeseleire Els
Published: July 2021

The presence of plant toxins and/or cyanotoxins in food supplements implies consumer health risks. Therefore, a targeted ultra-high performance liquid chromatographic-tandem mass spectrometric method to detect/quantify 25 toxins simultaneously in food supplement formulations was developed and validated. Full validation for tablets/powders and secondary validation for a liquid and soft gel capsule indicated that most compounds were efficiently extracted (≥ 75%), while others were only partly extracted (18 – 61%). Trueness was fulfilled (70 – 120%), with some exceptions (mostly at the lowest validation level). Intralaboratory repeatability, intra- and interlaboratory reproducibility values of ≤ 20%, ≤ 25%, and ≤ 25% were obtained for most, respectively. Matrix effects were found to be significant for most compounds. Good sensitivity (µg/kg level) was observed for galegin(e), lycopsamine, lycorine, rubiadin, skimmiamine, and vascin(e), in contrast to helveticoside, lucidin,
lucidin-3-primveroside, plumbagin(e), and thujone, which were detected at the mg/kg level. The other compounds were characterized by a sensitivity between 10 to 1000 µg/kg. The validated methodology was applied for 52 food supplements (tablets, capsules, liquids/syrup, etc.) purchased from the Belgian market. In more than 25% of the samples, one or more toxins were detected (concentrations determined using standard addition). Lycopsamine, microcystin LR, solamargine, thujone, and vasicin(e) were the most frequently detected toxins. A clear link between the toxins detected and the plant species on the food supplement ingredient list could not always be established. This generic “dilute-and-shoot” procedure can be used for further research on toxins in food supplements and by extension other plant/algae-based food/feed commodities (herbs, edible flowers, etc.).
Development and Validation of a Useful Taxonomy of Patient Portals Based on Characteristics of Patient Engagement
Authors: Glöggler Michael , Ammenwerth Elske
Published: July 2021

Objective Taxonomies are classification systems used to reduce complexity and better understand a domain. The present research aims to develop a useful taxonomy for health information managers to classify and compare patient portals based on characteristics appropriate to promote patient engagement. As a result, the taxonomy should contribute to understanding the differences and similarities of the portals. Further, the taxonomy shall support health information managers to more easily define which general type and functionalities of patient portals they need and to select the most suitable solution offered on the market.

Methods We followed the formal taxonomy-building method proposed by Nickerson et al. Based on a literature review, we created a preliminary taxonomy following the conceptional approach of the model. We then evaluated each taxa's appropriateness by analyzing and classifying 17 patient portals offered by software vendors and 11 patient portals offered by health care providers. After each iteration, we examined the achievement of the determined objective and subjective ending conditions.

Results After two conceptional approaches to create our taxonomy, and two empirical approaches to evaluate it, the final taxonomy consists of 20 dimensions and 49 characteristics. To make the taxonomy easy to comprehend, we assigned to the dimensions seven aspects related to patient engagement. These aspects are (1) portal design, (2) management, (3) communication, (4) instruction, (5) self-management, (6) self-determination, and (7) data management. The taxonomy is considered finished and useful after all ending conditions that defined beforehand have been fulfilled. We demonstrated that the taxonomy serves to understand the differences and similarities by comparing patient portals. We call our taxonomy “Taxonomy of Patient Portals based on Characteristics of Patient Engagement (TOPCOP).”

Conclusion We developed the first useful taxonomy for health information managers to classify and compare patient portals. The taxonomy is based on characteristics promoting patient engagement. With 20 dimensions and 49 characteristics, our taxonomy is particularly suitable to discriminate among patient portals and can easily be applied to compare portals. The TOPCOP taxonomy enables health information managers to better understand the differences and similarities of patient portals. Further, the taxonomy may help them to define the type and general functionalities needed. But it also supports them in searching and comparing patient portals offered on the market to select the most suitable solution.
Evaluation of the Performance of Direct Susceptibility Test by VITEK-2 from Positively Flagged Blood Culture Broth for Gram-Negative Bacilli
Authors: Kavipriya D , Prakash Suman Susan , Dhandapani Sarumathi , Rajshekar Deepashree , Sastry Apurba Sankar
Published: July 2021

Background Timely initiation of antimicrobial therapy in patients with blood stream infection is absolutely necessary to reduce mortality and morbidity. Most clinical microbiology laboratories use conventional methods for identification and antimicrobial susceptibility testing (AST) that involve biochemical methods for identification followed by AST by disk diffusion. The aim of the current study is to assess the various errors associated with direct susceptibility testing done from blood culture broth using automated AST system-Vitek-2 compact compared with the reference method of AST done from bacterial colonies.

Materials and Methods The study was conducted in a tertiary care public sector 2,200-bedded hospital in South India for a period of 6 months. The study involved positively flagged blood culture bottles that yielded single morphotype of Gram-negative organism by Gram stain. A total of 120 bacterial isolates were collected that consisted of consecutively obtained first 60 isolates of Enterobacteriaceae family (30 Escherichia coli and 30 Klebsiella pneumoniae) and consecutively obtained first 60 nonfermenters (30 Pseudomonas aeruginosa and 30 Acinetobacter baumannii). Vitek-2 AST was done from these 120 blood culture broth, following the protocol by Biomerieux, and results were obtained. Then, Vitek-2 was done from colonies (reference method) using appropriate panel for Enterobacteriaceae and nonfermenters, and results were obtained. Both the results were compared.

Results Nonfermenters showed a better categorical agreement of 97.6%, as compared to Enterobacteriaceae, which showed 97%. Among Enterobacteriaceae, both E. coli and K. pneumoniae showed categorical agreement of 97% each.

Conclusion The procedure of AST directly from blood culture broth represents a simple and effective technique that can reduce the turnaround time by 24 hours, which in turn benefits the clinician in appropriate utilization of antimicrobials for better patient care.
Robust optimal dispatch of interconnected micro-energy network based on cooperative game
Authors: Liang Ziwen , Mu Longhua , He Chuxuan
Published: July 2021

The micro-energy network is a subset of the electricity, gas, and heat energy grid. Due to its limited capacity, the energy and spare capacity of micro-energy network should be shared through interconnection. It can not only reduce the operating cost of the micro-energy network caused by power interchange deviation but also increase the consumption rate of intermittent distributed generation (IDG). On account of this assumption, a control structure and a double-layer dispatch model of the interconnected micro-energy network system are proposed in this paper. An economic dispatch model based on adaptive robust optimization is proposed to deal with the uncertainty produced by IDG and minimize the operation cost. Then, a cooperative game model of an interconnected system is built to allocate the profits obtained. Simulation results demonstrate that the proposed scheduling method can significantly reduce the cost of a single micro-energy network and interconnected system. In addition, compared to the noninteractive model and traditional deterministic method, it is proved that the proposed method has a strong capability to deal with uncertain risks, improve the consumption rate of IDG, and realize the coordinated economic optimal operation of multiple micro-energy networks.
Geometrical imaging accuracy, image quality and plan quality for prostate cancer treatments on a 1.5 T MRLinac in patients with a unilateral hip implant
Authors: van Lier A L H M W , Meijers L T C , Phillippens M E P , Hes J , Raaymakers B W , van der Voort van Zyp J R N , de Boer J C J
Published: July 2021

Purpose. To assess the feasibility of prostate cancer radiotherapy for patients with a hip implant on an 1.5 T MRI-Linac (MRL) in terms of geometrical image accuracy, image quality, and plan quality. Methods. Pretreatment MRI images on a 1.5 T MRL and 3 T MRI consisting of a T2-weighted 3D delineation scan and main magnetic field homogeneity (B
0) scan were performed in six patients with a unilateral hip implant. System specific geometrical errors due to gradient nonlinearity were determined for the MRL. Within the prostate and skin contour, B
0 inhomogeneity, gradient nonlinearity error and the total geometrical error (vector summation of the prior two) was determined. Image quality was determined by visually scoring the extent of implant-born image artifacts. A treatment planning study was performed on five patients to quantify the impact of the implant on plan quality, in which conventional MRL IMRT plans were created, as well as plans which avoid radiation through the left or right femur. Results. The total maximum geometrical error in the prostate was <1 mm and the skin contour <1.7 mm; in all cases the machine-specific gradient error was most dominant. The B
0 error for the MRlinac MRI could partly be predicted based on the pre-treatment 3 T scan. Image quality for all patients was sufficient at 1.5 T MRL. Plan comparison showed that, even with avoidance of the hips, in all cases sufficient target coverage could be obtained with similar D1cc and D5cc to rectum and bladder, while V28Gy was slightly poorer in only the rectum for femur avoidance. Conclusion. We showed that geometrical accuracy, image quality and plan quality for six prostate patients with a hip implant or hip fixation treated on a 1.5 T MRL did not show relevant deterioration for the used image settings, which allowed safe treatment.
Quantum entangled-probe scattering theory
Authors: Irfan Abu Ashik Md , Blackstone Patrick , Pynn Roger , Ortiz Gerardo
Published: July 2021

We develop an entangled-probe scattering theory, including quantum detection, that extends the scope of standard scattering approaches. We argue that these probes may be revolutionary in studying entangled matter such as unconventional phases of strongly correlated systems. Our presentation focuses on a neutron beam probe that is mode-entangled in spin and path as is experimentally realized by Shen et al (2020 Nat. Commun.
11 930), although similar ideas also apply to photon probes. We generalize the traditional van Hove theory (van Hove 1954 Phys. Rev.
95 249) whereby the magnetic response is written as a properly-crafted combination of two-point correlation functions. Tuning the probe’s entanglement length allows us to interrogate spatial scales of interest by analyzing interference patterns in the differential cross-section. Remarkably, for a spin dimer target we find that the typical Young-like interference pattern observed if the target state is un-entangled gets quantum erased when that state becomes maximally entangled.
Violation of equivalence principle in neutrino sector: probing the extended parameter space
Authors: Esmaili Arman
Published: July 2021

The oscillation of neutrino flavors, due to its interferometry nature, is extremely sensitive to the phase differences developing during the propagation of neutrinos. In this paper we investigate the effect of the Violation of Equivalence Principle (VEP) on the flavor oscillation probabilities of atmospheric and cosmic neutrinos observed at neutrino telescopes such as IceCube. Assuming a general parameterization of VEP, dubbed extended parameter space, we show that the synergy between the collected data of high energy atmospheric and cosmic neutrinos severely constrains the VEP parameters. Also, the projected sensitivity of IceCube-Gen2 to VEP parameters is discussed.
Testing homogeneity of the galaxy distribution in the SDSS using Renyi entropy
Authors: Pandey Biswajit , Sarkar Suman
Published: July 2021

We analyze a set of volume limited sample of galaxies from
the SDSS to study the issue of cosmic homogeneity. We use the Renyi
entropy of different order to probe the inhomogeneties present in
the galaxy distributions. We also calculate the Renyi diveregence to
quantify the deviations of the galaxy distribution from a
homogeneous Poisson distribution on different length scales. We
separately carry out the analysis using the overlapping spheres and
the independent voxels. Our analysis suggests that the scale of
homogeneity is underestimated in the smaller galaxy samples due to
the suppression of inhomogeneities by the overlapping of the
measuring speheres. We find that an analysis with the independent
voxels and/or use of a significantly larger galaxy sample can help
to circumvent or mitigate this problem. Combining the results from
these analyses, we find that the galaxy distribution in the SDSS
becomes homogeneous on a length scale beyond 140 h
-1 Mpc.
Is cosmological tuning fine or coarse?
Authors: Díaz-Pachón Daniel Andrés , Hössjer Ola , Marks II Robert J.
Published: July 2021

The fine-tuning of the universe for life, the idea that the constants of nature (or ratios between them) must belong to very small intervals in order for life to exist, has been debated by scientists for several decades. Several criticisms have emerged concerning probabilistic measurement of life-permitting intervals. Herein, a Bayesian statistical approach is used to assign an upper bound for the probability of tuning, which is invariant with respect to change of physical units, and under certain assumptions it is small whenever the life-permitting interval is small on a relative scale. The computation of the upper bound of the tuning probability is achieved by first assuming that the prior is chosen by the principle of maximum entropy (MaxEnt). The unknown parameters of this MaxEnt distribution are then handled in such a way that the weak anthropic principle is not violated. The MaxEnt assumption is “maximally noncommittal with regard to missing information.” This approach is sufficiently general to be applied to constants of current cosmological models, or to other constants possibly under different models. Application of the MaxEnt model reveals, for example, that the ratio of the universal gravitational constant to the square of the Hubble constant is finely tuned in some cases, whereas the amplitude of primordial fluctuations is not.
Effects of different organic fertilizer management modes on phosphorus and potassium content in wheat field
Authors: Shu Xiaoxiao , Qi Li , Wang Qingyi
Published: July 2021

In order to study the effects of different organic fertilizer management modes on soil nutrient content in wheat field, and provide scientific basis for agricultural production. In this paper, the changes of soil phosphorus and potassium content in wheat field were studied by setting low, medium and high amounts of organic fertilizer, combined with different tillage methods, such as no tillage, tillage, subsoiling and subsoiling tillage. The results showed that: low amount of organic fertilizer combined with tillage and medium amount of organic fertilizer combined with no tillage were conducive to increase the content of soil available potassium. Comprehensive analysis suggested that the region should avoid applying high amount of organic fertilizer and adopt low amount of organic fertilizer combined with no tillage measures, which could help to improve soil fertility.
Study on Sedimentary Characteristics of S0 Reservoir in BBK Area
Authors: Li Yanli
Published: July 2021

The S0 reservoir in the BBK area is a reevaluation of unused development resources. According to the change trend of oilfield production tasks, the development test of the S0 reservoir is imperative, but the sedimentary characteristics of the reservoir have not yet been perfected; the author uses core, logging curve and various analysis and test data to describe the sedimentary facies of the S0 reservoir in detail, through the method of the combination of quantitative and qualitative sand body comprehensive identification. First, refer to the effective thickness, permeability, frequency of the interlayer development and other parameters of the sand body in the work area to quantitatively determine the microfacies. Then, combined with the electrical survey chart of typical microfacies, the microfacies types of sand bodies of single-well single-layer are qualitatively determined. Finally, the comprehensive judgment results are calibrated in the facies zone base map, which is used for the analysis of the overall distribution law of each microfacies and the precise positioning of the sand body boundary; it is concluded that the underwater distributary channel sand body of the S0 oil layer is not developed, and the outer front sheet sand is developed in a large area through the analysis of the judgment results of sedimentary microfacies. Generally speaking, it belongs to the subfacies deposits in the outer front of the delta, which provides a favorable geological basis for later development adjustment and effect evaluation.
Research on safe and efficient drilling technology of soft outburst coal seam
Authors: Hao Cao
Published: July 2021

In soft coal bedding drilling hard into the problem of hole, based on the drilling of coal in the process of motion, from two aspects to improve the traditional drilling technology, selection of high power, large torque drill and selecting reasonable parameters of drilling tools and better way of powder, formed a “high power drill, shallow blade spiral drill pipe, wind pressure in the wind” of the construction process. The field application test was carried out in Xinxin Coal Mine of Yunnan Province, and the test results show that the average monthly footage of drilling rig is 8000 m/rig•month. The average depth is 137m, the primary pore formation rate reaches 90%. Compared with the original drilling technology, the new technology increases the average hole depth by 12%∼70%, the drilling efficiency by 30%∼46%, the extraction concentration by more than one time, and the single hole extraction amount by 33.6%. The drilling technology of soft outburst coal seam has improved the drilling efficiency and realized the full coverage of gas drainage in working face, which is worthy of reference and reference in soft coal seam mine.
Analysis of the running capacity of coiled tubing in three-dimensional curved borehole
Authors: Cao Yinping , Pan Ying , Mi Hongxue , Wang Jianxing , Niu Zhanshan , Dou Yihua
Published: July 2021

When coiled tubing enters three-dimensional borehole, elastic deformation is very easy to occur, leading to the decrease of running depth. In order to study the running capacity of coiled tubing, the running friction of coiled tubing under sinusoidal buckling and helical buckling in three-dimensional borehole was analyzed according to the structure of coiled tubing and the characteristics of borehole trajectory, considering the different contact points between the coiled tubing load and the borehole wall. According to the friction analysis results of each section of the running coiled tubing, the torque balance differential equation of the running coiled tubing micro-element was established and solved, and the friction torque of the running coiled tubing was obtained. The running capacity of Φ38.1mm×2.6mm QT-900 coiled tubing in three-dimensional borehole is analyzed. A theoretical algorithm for analyzing the running capacity of coiled tubing is established through the analysis of an example. This research can provide important theoretical research value and practical significance for the analysis of the running capacity of coiled tubing.
Study of a New Method for Calculating Critical Liquid Carrying Flow Rate of Gas Wells
Authors: Huang Yi , Liu Shujie , Meng Wenbo , Jiang Donglei , Yu Yi , Ren Guanlong
Published: July 2021

The minimum critical liquid carrying flow rate of gas wells is an important parameter in the process of making gas reservoir development plans. At present, Turner equation and Li Min equation in the field are mainly used to calculate the critical liquid carrying flow rate of gas wells. However, the two equations have some limitations, which do not consider the effect of interfacial tension on the critical liquid carrying flow rate. In calculation, the gas-water interfacial tension is simplified as a constant, but interfacial tension is a function of temperature and pressure. In order to calculate the minimum liquid carrying flow rate more accurately, the existing calculation equation is modified while considering the influence of temperature and pressure on interfacial tension. The equation of minimum production is obtained by deducing the minimum flow rate of liquid carrying in gas wells. The actual gas well data is used for example calculation, and the minimum production under different well depth, bottom hole temperature and pressure is analyzed. The results show that considering the interfacial tension when calculating the fluid carrying flow rate of gas wells, the calculated fluid carrying flow rate of gas wells is more realistic.
A New Method for Evaluating Gas Well Boundary Characteristics
Authors: Meng Wenbo , Huang Yi , Liu Shujie , Jiang Donglei , Yu Yi , Ren Guanlong
Published: July 2021

In evaluating the reservoir physical properties and boundary characteristics of gas wells, the well test interpretation method is mainly employed currently to obtain K, KH, S and boundary characteristics of the reservoir. This method requires a test system for gas wells and a pressure gauge to record the data of flowing bottom hole pressure (FBHP) at the middle depth of the gas reservoir, with long testing time and high cost. Therefore, productivity testing and test pressure recovery data are only performed for some gas wells, and we cannot get reservoir physical property parameters by well test interpretation. It is considered that this method can better meet the needs of practical work, and has high popularization and application value.
Physical threshold of high quality reservoir of Upper Paleozoic in Daniudi gas field, Ordos Basin
Authors: Xu Ningning
Published: July 2021

Combined with the gas content and physical property data of the reservoirs, physical threshold of the Upper Paleozoic high quality reservoirs in Daniudi gas field, Ordos Basin is defined through the definition of effective reservoirs, using the method of oil test and distribution function. The results show that the threshold of porosity and permeability is 8% and 0.6×10−3μm2, respectively. The distribution function method shows that the physical threshold of the low-producing reservoir (with a daily gas production of more than 5 000 m3) is 8∼9% porosity and 0.6∼0.8×10−3μm2 permeability. Based on comprehensive analysis, porosity of 8% and permeability of 0.6×10−3μm2 are set as the physical threshold of high quality reservoir.
Research of tight gas reservoir simulation technology
Authors: Zhang Wanneng , Cheng Zhaoyuan , Cheng Hanlie , Qin Qiang , Wang Minghao
Published: July 2021

The stimulation of tight gas reservoir in Linxing block of Shanxi Province has always been a difficult problem. This paper describes and analyzes the formation lithology, physical properties and sensitivity of the reservoir. And introduces the pulse power technology and controllable shock wave technology, and focuses on the research and analysis of the latter. The results of field test show that: In the application of plug removal and permeability enhancement of low permeability tight gas oil and gas wells in medium and shallow wells (well depth less than 3000m), the controllable shock wave technology has achieved good results in increasing production and injection. Field application shows that the technology is basically mature and can be further promoted. Compared with traditional technologies such as acidizing and plugging removal, controllable shock wave technology has the advantages of layered implementation, strong pertinence, simple operation, wide adaptability and better effect.
Research and Application of Chemical Regulating Technology for ISC Injection-Production Wells in Liaohe Oilfield
Authors: Wang Siwen
Published: July 2021

In Situ Combustion (ISC) Technology is an effective replacement method of oil recovery after Heavy Oil Cyclic Steam Stimulation (CSS) and Steam Flooding (SF). At present, ISC Technology has been carried out mainly in Du 66, Shu 13832, Gao 3618 and Jin 91 blocks of Liaohe Oilfield. However, during the ISC development process, due to the heterogeneity of reservoir growth, the uneven propulsion of fire lines and gas channeling will affect the development effect of ISC reservoir. In this paper, the chemical regulating technology proposed in this paper could improve air injection efficiency, solve the gas channeling problem of production wells, expand the swept volume of air injection and increase the recovery rate of ISC.
Study on Water Plugging Technology Outside Drivepipe of Oil Well
Authors: Li Rui
Published: July 2021

A new chemical water shutoff agent was developed to solve the problem of casing water flowing out of production wells in Liaohe Oilfield. Under the specific process conditions, the new chemical water shutoff agent can be injected into the position where the water goes out of the casing. The solidified water plugging agent can form a high strength, high temperature resistant and impermeable barrier laye.t can achieve the purpose of secondary cementing and casing protection. The water plugging agent has been applied in the field and has achieved good effect of oil increase and precipitation.
Research on uniaxial compression of jointed rock mass based on numerical simulation
Authors: Yin Yantian , Li Guilin , Liu Yang , Jiang Xiang , Luan Weijie
Published: July 2021

Jointed rock mass is a material with anisotropic strength and coexistence of continuous and discontinuous media. In order to study the mechanical behavior of rock mass impacted by the spatial distribution of joints, RFPA2D, which is a discrete element geotechnical engineering simulation, is employed in this paper. Based on the basic rock mechanical parameters obtained from uniaxial compression experiment, the influence of joint inclination angle on rock strength and strain path is explored. The simulation results show that: Cracks will cause large initial damage to the rock mass, resulting in a significant decrease in the peak strength of the specimen compared with the intact rock mass. Meanwhile, it decreases the stage of elastic deformation, and it has the strongest impact to strain path when joint angle equals to 90°.
Formation Mechanisms and Distribution Law of Effective Volcanic Reservoirs -- Taking Carboniferous Volcanic Reservoirs in Malang Depression of Santanghu Basin as an Example
Authors: Yang Wenmin
Published: July 2021

The understanding of the formation mechanisms of volcanic reservoirs can provide a reference for the distribution law of effective volcanic reservoirs and oil and gas reservoirs, and has an important guiding role in accelerating the pace of the exploration and development of volcanic reservoirs. Using the data of three-dimensional seismic interpretation, logging, core description and thin section identification, it is concluded that the formation of volcanic reservoirs in Santanghu Basin was controlled by many factors such as tectonics, lithology, lithofacies, fluids, volcanic apparatus, weathering and leaching, including fault rebuilt, unconformity, alkali metasomatism, dissolution, weathering and leaching and other formation mechanisms, 5 types of reservoir formation models are obtained according to the different superimposition modes of the depth mechanism for the formation of volcanic reservoirs in different periods, and five types of distribution law of effective volcanic oil and gas reservoirs are summarized from the understanding of reservoir types, accumulation models, and accumulation mechanisms. The study provides a reference for the prediction of effective volcanic reservoirs, and further defines the exploration direction of volcanic oil and gas reservoirs.
Closed-form Solution of Prestressed Composite Beam Deformation
Authors: Wang Linfei
Published: July 2021

Eccentric load effect of prestressing in composite beam leads to nonlinear coupling oof deflection-slip. For the prestressed composite beam, considering axial force and eccentric moment of the prestressing equivalent load, variational equilibrium equations are imposed by the virtual work theorem which involves the interfacial slip condition. With relevant boundary conditions of different structural form, the closed-form solution can be derived. The model and closed-form solution are then validated by means of finite element analysis.
Study on slope reinforcement scheme of roadbed under relatively large height difference conditions
Authors: Qian Jin , He Xiaoling , Liu Dejun
Published: July 2021

This paper takes the high slope project of Deqing station as the research background, evaluates the stability of the project slope through on-site engineering geological investigation, theoretical analysis and numerical simulation calculation, proposes the reinforcement treatment plan according to the stability state of the project slope, and analyzes the feasibility and effectiveness of the reinforcement treatment plan of soil slope by using the combination of on-site implementation and on-site monitoring and other means. The change of safety coefficient of the slope before and after reinforcement is compared, and a simple and effective reinforcement measure is proposed to face the high slope.
Study on the surrounding rock parameters deterioration and weathered away into soil in deep buried soft rock tunnel excavated by TBM
Authors: Li Jinqi , Ma Shuai , Xie Wenbin , Wang Shuai , Liu Gao
Published: July 2021

In the engineering fact that excavation will lead to the deterioration of rock parameters in the excavation damage zone of tunnel, based on a diversion tunnel by simulating the continuous dynamic adjustment process of surrounding rock parameters, the dynamic deterioration law of surrounding rock parameters in deep buried soft rock tunnel is studied. It is considered that the deterioration of surrounding rock parameters in the damaged area of deep buried soft rock tunnel constructed by TBM is a continuous process. After the excavation, the angle of friction φ increases, the cohesive strength C decreases, and the supporting structure of the tunnel have a limiting effect on the deterioration of surrounding rock parameters.
A novel hybrid krill herd algorithm for modeling solid oxide fuel cells
Authors: Xu Caiyun , Zhou Yongsheng
Published: July 2021

Solid oxide fuel cells are globally recognized as a very promising technology in the area of highly efficient electricity generation with a low environmental impact. In this paper, a novel hybrid krill herd algorithm (nhKHA) is proposed for modeling the solid oxide fuel cells (SOFCs). In nhKHA, the operation inspired by the foraging behavior of fish-swarm is adopted to improve the global search ability, and the operation inspired by the virus search is used to improve the search efficiency and accuracy. The nhKHA is applied to optimize the parameters of the SOFC, the experiment results show that this nhKHA can achieve more higher precision between mathematical model and experimental data compared with some other optimization algorithms.
The application research of Sunken hidden anchor bolt foundation in 1000kV UHV substation
Authors: Fu Yanwei
Published: July 2021

This paper mainly deals with the efficient utilization of the land occupied by the permanent foundation of temporary buildings. The main transformer maintenance workshop is set up in the 1000kV UHV substation for the main transformer fault phase maintenance. The main transformer maintenance workshop is of prefabricated steel structure. During the substation operation, only the permanent foundation is retained. Once the main transformer needs maintenance, the maintenance party shall bring steel structure components to the site for workshop construction. After the overhaul, the overhaul party will remove the steel structure and take it away for the site or other stations to continue to use, while the permanent foundation will continue to be retained.