bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative analysis of microstructure and mechanical properties of Nb–V microalloyed high-strength seismic reinforcement with different Nb additions
Authors: Huang Sheng , Li Changrong , Li Zhiying , Zeng Zeyun , Zhai Yongqiang , Wang Jie , Liu Zhanlin , Zhuang Changling 
Published: September 2021

Abstract
HRB500E seismic steel bars are mainly used in high-rise buildings near the seismic zone. The influence of different niobium contents (0–0.023%) on the microstructure and mechanical properties of HRB500E seismic reinforcement was studied. Results showed that the grain size of ferrite was between 3.6 and 8.3 μm when only V was added. Meanwhile, as the niobium content increases, the ferrite particles are further refined. After adding niobium, the grain contribution increased by 9%. The addition of niobium significantly refined the grain size of HRB500E seismic reinforcement. The second-phase nano-elliptic precipitate is NbC. The precipitated phase is dispersed on the grain boundary and the matrix, and the dislocation density on the matrix promotes the precipitation of NbC particles along the dislocation line. The second-phase precipitation of niobium can form an effective pinning effect and then refine the pearlite spacing. The microhardness and the tensile strength also significantly improved. The yield strength increased from 509 to 570 MPa.
Hybrid WDM free space optical system using CSRZ and Rayleigh backscattering noise mitigation
Authors: Kaur Rupinder , Singh Charanjit , Kaur Rajbir 
Published: September 2021

Abstract
Hybrid wavelength-division-multiplexing (WDM) and free space optical (FSO) access networks are getting great attention due to numerous advantages. In this work, hybrid WDM-FSO system is demonstrated for 55 km at capacity of 5 × 10 Gbit/s using compressed spectrum return to zero (CSRZ) WDM-FSO in downstream and nonreturn to zero (NRZ) in upstream for demonstrating transmitter diversity which inturn decrease the interchannel interference. For the suppression of Rayleigh backscattering (RB) interferometric beat noise, bidirectional cyclic multiplexer is employed. Cyclic multiplexer provide λ
1 to λ
5 wavelengths for optical line terminal (OLT) to ONU transmission and λ
2 to λ
6 for ONU to OLT transmission. Insertion losses of each component are considered and in the end, power budget is also calculated. Results revealed that FSO length of 780–1050 m are obtained using various WDM-FSO downstream signals and their power budget, redundant budget, maximum distance, and insertion losses also calculated.
Burnout and Perceptions of Stigma and Help-Seeking Behavior Among Pediatric Fellows
Authors: Weiss Anna K. , Quinn Sheila M. , Danley Amy L. , Wiens Kandi J. , Mehta Jay J. 
Published: September 2021

BACKGROUND AND OBJECTIVES
Although burnout has been studied extensively among students and residents, in few studies have researchers examined burnout among fellowship trainees. We measured burnout among fellows in our freestanding children’s hospital and evaluated fellows' perceptions of stigma around (and willingness to seek treatment for) psychological distress. The objectives are as follows: to (1) measure burnout among pediatric fellows, (2) assess fellows' perceptions of stigma around help seeking for mental illness, and (3) examine the relationship between burnout and willingness to seek behavioral health counseling.

METHODS
We distributed a 48-item inventory to all 288 fellows in our pediatric center. Items included the Maslach Burnout Inventory and Likert-type matrices to assess attitudes toward behavioral health treatment and associated stigma. We used 2-sampled t-tests to associate burnout with willingness to seek mental health treatment.

RESULTS
A total of 152 fellows (52%) responded, of whom 53% met the threshold for burnout. Most reported believing that their program directors (78%), attending physicians (72%), and patients (82%) hold negative attitudes about mental illness and its treatment; 68% believed that employers would reject their application if they knew they sought counseling. Fellows with burnout were more likely to believe that others in the clinical learning environment hold negative views of help seeking for behavioral health (odds ratio 1.2–1.9).

CONCLUSIONS
Just over one-half of the pediatric fellows in our center meet the threshold for burnout. They also experience significant workplace-based stigma around help seeking for psychological distress. Fellows with burnout are more likely than their peers to perceive significant stigma around help seeking for their distress, making them a particularly at-risk learner population.
Estimation of coefficient of performance of thermoelectric cooler using a 30 W single-stage type
Authors: Ibikunle Rotimi Adedayo , Akintunde Mutalubi Aremu , Titiladunayo Isaac Femi , Adeleke Adekunle Akanni 
Published: September 2021

Abstract
In this study, a single stage thermoelectric cooler (TER, of size: 21 × 14.2 × 13.5 cm) with thermoelectric module (TEM, of type inbc1-127. 05 with size 40 × 40 × 4.0 mm) and applied electrical power of 30 W and current of 2.5 A, was adopted to estimate the coefficient of performance (COP) of thermoelectric refrigerator (TER). The TER uses a fan to cool the heat exchange region of the TEM. The temperature of the fruit/vegetable samples used in this study was taken before and after cooling for a specific period. The temperatures at both the hot and cold sides of the TEM were also taken at every specific cooling period. The experimented TER can cool vegetable/fruit from about 27 to 5°C within 3 h. The aim of this study is to determine the COP of TER to ascertain the possible applications. The temperature gradient at the heat exchange section of TEM was used to estimate the average theoretical COP to be 0.99, the heat extracted from the cooling chamber and the power supplied was used to estimate the average practical cooling COP to be 0.52; which is within 0.4–0.7 standard COP for a single stage type of TER.
The seroprevalence of human brucellosis in different age groups patients and other associated risk factors in Duhok, Iraq
Authors: Assafi Mahde S , Allu Muslim A , Abdulrahman Ibtesam S , Al-Berfkani Mohammad I 
Published: September 2021

Introduction: Brucellosis is a zoonotic disease contributing to significant health and economic problems worldwide. The aim of this study was to investigate the seroprevalence and the associated risk factors of brucellosis among people admitted to Azadi general hospital, Duhok, Iraq. Patients and Methods: A total of 1283 patient blood samples (603 males and 680 females) were collected through the period of January 2017 to December 2017 from people at different age groups admitting Azadi general hospital, Duhok, Iraq. All collected sera were screened for the seroprevalence of Brucella using Rose Bengal plate test kit. Results: Among the 1283 blood samples, the overall seroprevalence of brucellosis was 17.8%. The highest rate was recorded in age group between 21–30 years(22.7%) and the different distribution of human brucellosis among age groups was statistically significant (p=0.0076). The frequency of brucellosis in females (20%) was significantly higher than males (15.3%) (p=026). The distribution of brucellosis according to the seasonal changes was statistically significant (p= 0.003) (25.64% in July and 9.75% in December). Conclusions: The incidence of the brucellosis is high, and it remains a challenging health problem. The age, gender, and seasonal changes are considered as important risk factors for the distribution of the diseases. Surveillance programs and active screening for brucellosis are essential to prevent, control, and to reduce the incidence of the brucellosis.
La creación curricular en la formación de educadores
Authors: Orozco-Martínez Susana , Pañagua Domínguez Laura , Martos-Pérez María-Victoria 
Published: September 2021

En el presente artículo[1] se comparte una mirada sobre posibles modos en que las relaciones educativas, sostenidas con cuidado y atención, contribuyen a desplegar no solo el currículum prescrito de forma teórica, sino de una manera más experiencial en el aula universitaria. Buscamos compartir cómo la práctica de indagar y pensar sobre las experiencias escolares y las que se van viviendo en el aula, permiten a cada uno/a ir creando y recreando elementos curriculares, desde una mirada singular, pedagógica. Con este trabajo se pretende: a) ahondar en los modos en cómo una disposición a la relación educativa puede cultivar el pensar y repensarnos como docentes, b) explorar cómo la formación puede constituirse en una experiencia de creación y, c) reconocer aquellas prácticas docentes que puedan favorecer a los procesos de creación y recreación del currículum en la formación de educadores/as. Para ello, recurrimos a la indagación narrativa (Clandinin y Connelly, 2000), porque nos posibilita apelar a la experiencia vivida y al devenir de la clase, desde una visión del currículum como un entramado único y singular que se va generando entre quienes van al encuentro de la relación educativa. Esta perspectiva nos ha posibilitado analizar cómo al acoger lo imprevisible que surge en la clase, se vivifican los procesos formativos, dando lugar a experiencias y aprendizajes cuyo valor excede lo previsto en el plan docente, abriendo nuevos elementos pedagógicos para pensar el oficio de educador/a.

[1] Este artículo es fruto del proyecto de investigación “Relaciones educativas y creación del currículum: entre la experiencia escolar y la formación inicial del profesorado. Indagaciones narrativas” (EDU2016-77576-P) (AEI/FEDER, UE).
Attenuation of the Lg phase and the determination of mb in the southeastern United States
Authors: Bollinger G. A. 
Published: September 2021

abstract
A study of the Lg radiation from 17 southeastern U.S. earthquakes shows the attenuation of that phase to be at a 0.07°−1 rate for epicentral distances of 100 to 700 km. At longer distances, it is also at that rate for some of the earthquakes, but for five of the events it was at a somewhat greater (0.10°−1) rate. These different Lg attenuation rates are clearly a distance-related effect, but they are not caused by differences in source area, propagation path, radiation pattern, wave period, or group velocity. A possible explanation for the different attenuation rates is a shift from a normal-mode form of propagation to a leaking-mode form, brought about by slight phase-velocity variations in the crustal wave guide and/or in the underlying layer. Also, the influence of lateral heterogeneity and variations in the thickness of the crustal wave guide offer alternative explanations.
Nuttli's (1973) mb (Lg) formulas, determined for central U.S. events, were found to be appropriate for use on southeastern U.S. shocks if their application is restricted to epicentral distances less than 2,000 km. This distance-restriction result agrees with that determined for the northeastern U.S. earthquakes by Street (1976).
Seismic system calibration: 1. Parametric models
Authors: Farrell W. E. , Berger J. 
Published: September 2021

abstractWe describe linear models of the IDA (International Deployment of Accelerometers) and SRO (Seismic Research Observatories) feedback seismometers obtained by straightforward analysis of the control systems. The most important property of these models is the theoretical transfer function they yield, relating Earth acceleration to output voltage. The parameterization of the theoretical transfer function is described. Several uses of the system models and transfer function are discussed, but we conclude that the parameterized models do not provide a sufficiently accurate means of describing the installed accelerometer's behavior. A speedier, more automatic and more accurate calibration can be obtained by electrically perturbing the seismometer system. This technique is discussed in Part 2.
Secondary faulting near the terminus of a seismogenic strike-slip fault: Aftershocks of the 1976 Guatemala earthquake
Authors: Langer C. J. , Bollinger G. A. 
Published: September 2021

abstract
Aftershocks of the February 4, 1976 Guatemalan earthquake (Ms = 7.5) were monitored by a network of portable seismographs from February 9 to February 27. Although seismic data were obtained all along the 230-km surface rupture of the causal Motagua fault, the field program was designed to concentrate on the aftershock activity at the western terminus of the fault. Data from that locale revealed several linear or near-linear trends of aftershock epicenters that splay to the southwest away from the western end of the main fault. These trends correlate spatially with mapped surface lineaments and, to some degree, with ground breakage patterns near Guatemala City. The observed splay pattern of aftershocks and the normal-faulting mode of the splay earthquakes determined from composite focal mechanism solutions, may be explained by a theoretical pattern of stress trajectories at the terminus of a strike-slip fault. Composite focal mechanism solutions for aftershocks located on or near the surface break of the Motagua fault, to the north and east of the linear trend splay area, agree with the mapped surface movements, i.e., left-lateral strike-slip.
Source mechanism and surface-wave attenuation studies for Tibet earthquake of July 14, 1973
Authors: Singh D. D. , Gupta Harsh K. 
Published: September 2021

abstract
Focal mechanism for Tibet earthquake of July 14, 1973 (M = 6.9, mb = 6.0) has been determined using the P-wave first motions, S-wave polarization angles, and surface-wave spectral data. A normal faulting is obtained with a plane having strike N3°W, dip 51°W, and slip angle 81°. The source parameters have been estimated for this event using the body- and surface-wave spectra. The seismic moment, fault length, apparent stress, stress drop, seismic energy release, average dislocation, and fault area are estimated to be 2.96 × 1026 dyne-cm, 27.4 km, 14 bars, 51 bars, 1.4 × 1022 ergs, 157 cm, and 628 km2, respectively. The high stress drop and apparent stress associated with this earthquake indicate that the high stresses are prevailing in this region. The specific quality factor Q is found to vary from 21 to 1162 and 22 to 1110 for Rayleigh and Love waves, respectively. These wide ranges of variation in the attenuation data may be due to the presence of heterogeneity in the crust and upper mantle.
A study of earthquakes in the Permian Basin of Texas-New Mexico
Authors: Rogers A. M. , Malkiel A. 
Published: September 2021

abstractA microearthquake seismograph network has been employed to study earthquakes occurring in the Permian Basin of Texas and New Mexico. The earthquakes are predominantly located on the Central Basin platform, although a few occur in the Delaware Basin. The majority of the earthquakes occur at the depths of sedimentary rocks, and the focal depths are also coincident with the depths at which hydrocarbon production and water-flood (secondary recovery) operations are conducted. Comparison of the historic earthquake activity with water-flood data shows that there was a possible increase in the number of large earthquakes (M &gt; 3.0) in the mid-1960's when the number of water-flood projects and their injection pressures increased. The first felt event occurred in 1966. This tentative correlation suggests that the earthquakes are related to hydrocarbon production in this area.
Estimate of the focal depth of deep earthquakes and some structural implications for the deep seismic activity in the Tyrrhenian region
Authors: Bottari A. , Federico B. 
Published: September 2021

abstract
We describe a method for determining the depth of deep earthquakes utilizing the travel-time differences TS - TP and TPdP - TP relative to P, S, and PdP waves (Pdp indicates P waves reflected off the 20° discontinuity), observed at a single station.
This method has provided valid results and the values calculated for about 20 earthquakes in the Tyrrhenian and Greek areas show differences in the region of ± 10 and ± 15 km, respectively when compared with the corresponding values obtained by statistical methods.
Starting from an analysis of the spatial distribution of 48 intermediate and deep foci in the Tyrrhenian area and from the study of travel-time residuals and of the initial motion at MES, we go on to a critical examination of a number of hypotheses regarding the deep structure of the area examined.
The spatial distribution and the data gathered agree with a certain number of physical parameters characteristic of an underlying lithospheric slab, which appears to be the most valid structural model for the southern Tyrrhenian region, for which one can estimate a frontage of ∼250 km, an average dip of 46°, and an azimuth of 297°. In the last 40 years the major seismic area has been that between 220 and 340 km in depth, corresponding to the zone under maximum tension. Instead, the slab's terminal zone, beyond a depth of 430 km, appears to be under compression.
Human perception of T waves: The June 22, 1977 Tonga earthquake felt on Tahiti
Authors: Talandier Jacques , Okal Emile A. 
Published: September 2021

abstract
We report human perception of seismic waves generated on the island of Tahiti by exceptionally large T waves, following a major earthquake in the Tonga area. The generation mechanism of the T waves and their smaller amplitudes at other Pacific stations are explained in relation to source and receiver bathymetry, focal mechanism, and magnitude of the event. It is concluded that a series of favorable path conditions, rather than the size of the event (Ms = 7.8; Mw = 8.1), were responsible for the giant T waves felt at Tahiti.
Public policy issues: Earthquake prediction
Authors: Paté Marie-Elisabeth , Shah Haresh C. 
Published: September 2021

abstract
The object of this paper is to provide a method of cost-benefit analysis of earthquake prediction as a means of mitigation of earthquake effects. The research in earthquake prediction may or may not be successful and involves an initial cost. Earthquake prediction, if achieved, on the one hand provides society with information which allows it to take protective measures. On the other hand, each prediction involves the costs of those measures and the consequent disruption of economic life. The question is to assess the value of such information in a given state of the prediction technology.
The evaluation of a fault-monitoring program and its consequences for the public at the time of predictions is performed over a 50-year period. A rate of growth, a social rate of discount, and a rate of improvement over time of earthquake prediction techniques are assumed.
A model “TREE” is developed; it allows computation, for each year, of the expected value of the earthquake prediction information—expected costs minus expected benefits. The life component and the dollar component of the net result are kept separate throughout the evaluation.
The final result is an expected cost per life saved through the earthquake prediction program over a 50-year time period. This allows comparison with the results of earthquake engineering and building codes (see Paté, 1978). It also allows comparison with the results obtained in other public sectors involving risk mitigation—health and transportation, for example.
A numerical example has been worked out for the case of the San Francisco Bay Area; it gives a first approach to the results that can be expected from a prediction system with different assumptions on the success of research in that field.
This paper is based on the doctoral thesis at Stanford University of M-E. Paté, under the supervision of Professor H. C. Shah.
Earthquake faulting and bedding thrust associated with the Tabas-e-Golshan (Iran) earthquake of September 16, 1978
Authors: Berberian M. 
Published: September 2021

abstractThe Tabas-e-Golshan earthquake of magnitude Ms = 7.7 occurred in a region of east central Iran known to have been quiescent for at least 11 centuries. The shock was associated with 85 km of discontinuous thrust faulting at the surface along an existing but unrecognized late Quaternary fault (the Tabas Fault). Nearly all the surface breaks followed the obvious scarps created by the previous faulting. An extensive zone of “bedding thrusts” (bedding-plane slip) was also developed in the Neogene clay deposits of the overthrust block, east of the main fault zone. Minimum vertical uplift (throw) and slip measured at about 150 and 300 cm, respectively. The deformation caused by this earthquake indicates crustal thickening of the region, i.e. uplifting along the earthquake fault. The Tabas Fault is one of the principal structures by which the western flank of the Shotori mountains is raised about 2 km above the alluvial deposits of the Tabas compressional graben. It is a multi-role deep-seated Precambrian fault and one of the major features during Paleozoic and Mesozoic, in the western part of the fault-controlled subsiding sedimentary basin of Shotori.The earthquake killed more than 20,000 people and severely damaged or destroyed about 90 villages together with the town of Tabas. This catastrophic event emphasizes once more the importance of mapping recent faults and the careful field study of structures associated with low-magnitude buried earthquakes. In the case of Tabas, the lack of historical seismic damage over the past 11 centuries meant that there was no adequate assessment of the seismicity and seismic hazard on this basis. A comparison of the Plio-Pleistocene and Late Quaternary crustal deformation with that associated with this earthquake indicates the intra-plate deformation to be essentially unchanging since that time, and the regional stress field to be not greatly changed since the late Alpine phase.The present state of knowledge about regional tectonics and seismicity suggests the country to be a broad zone of compressional deformation, the present deformation being taken up mostly by the existing late Quaternary mountain-bordering reverse faults inherited from the old geological times. The seismicity is widespread along several faults and the continental crust is thickening and shortening in the NE-SW direction.
Autoregressive parameters for a suite of strong-motion accelerograms
Authors: Jurkevics Andrejs , Ulrych Tad J. 
Published: September 2021

abstract
The time-adaptive technique of Jurkevics and Ulrych (1978) has been used to analyze a suite of rock-site accelerograms recorded during two ML = 6.4 earthquakes in California. One of the parameters which models the earthquake, the innovation variance σe2, has been found to vary with epicentral distance according to (σe2)max ∝ D-3.23. The shaking duration exhibits a linear variation with log(D) after a finite distance away from the fault. The above results allow the construction of artificial accelerograms for arbitrary epicentral distances ML = 6.4 earthquakes in California.
Comparative evaluation of fine detail reproduction of six different die materials- An in-Vitro study
Authors: Mukhopadhyay Pronoy , Wankhade Sattyam , Wankhade Jyoti , Khalikar Arun 
Published: September 2021

The precise outcome of any indirect casting, depends on the various procedures and materials involved through all its stages. The accurate fit against the prepared surface and the adaptation against the prepared margin depends on how accurately the tooth surface is captured in the impression made and how well it is reproduced in the die This study aims to study and compare the property of fine detail reproduction amongst six die materials.Over a pre-calibrated master die using custom tray, an impression record is made and poured using the six different die materials and the finest line reproduced is visualized under an optical fluorescent microscope at 50X magnification.The data obtained were statistically analysed using one-way ANOVA and subsequently assessed by post-hoc Tukey’s comparison to identify any significant differences between the groups. Epoxy resin die material (1.93 mm) showed a consistently excellent fine detail reproduction, followed by conventional Type V gypsum and Synthetic gypsum (15.91 mm), while Resin modified-Type IV and Type V and conventional Type IV gypsum dies (21.86mm) showed the least accuracy in fine reproduction.