bluuebunny/crossref_metadata_2025_split huggingface dataset:
Some sixteenth century European earthquakes as depicted in contemporary sources
Authors: Deresiewicz H. 
Published: June 2021

Abstract
Illustrated accounts of a number of 16th century earthquakes and volcanic eruptions are presented, collected from literature contemporary with the events. Although for the most part describing occurrences known from the comprehensive catalogs of the 19th and early 20th centuries, the accounts given here provide many more details and yield interesting historical insights and divergences.
A new procedure for processing strong-motion earthquake signals
Authors: Sunder S. Shyam , Connor Jerome J. 
Published: June 2021

Abstract
A new procedure for routinely processing strong-motion earthquake signals using state-of-the-art filter design and implementation techniques is presented. The model, shown to be both accuratet and efficient, is sufficiently flexible so that the signal sampling period and filter parameters can be easily varied. A comparison of results from the existing United States model (Trifunac and Lee, 1973) and the proposed model show significant differences in the ground motion and response spectrum characteristics for the same set of filter limits. Drifts in integrated velocity and displacement characteristics and theoretically incorrect asymptotic behavior of response spectrum curves arising out of the existing United States processing scheme have been eliminated. In addition to the importance of appropriately selecting a low-frequency limit for band-pass filtering the signals, this work demonstrates the sensitivity of the acceleration trace to the particular choice of a high-frequency limit.
The inverse problem of the density and bulk modulus profiles of a layered fluid
Authors: Coen Shimon 
Published: June 2021

abstract
It is shown that the density and bulk modulus profiles of a layered fluid half-space are uniquely determined from the vertical component of the particle velocity on the surface due to an impulsive point source on the surface. In addition, an estimate of the highest acoustic wave velocity in the layered half-space is required as well. The necessary conditions for the existence of the solution are discussed and a direct (noniterative) inversion algorithm is developed which constructs the density and bulk modulus profiles of the half-space from the surface data. The main limitations of this theory to real seismic data are briefly discussed.
A note on near-source estimates of local magnitude
Authors: Enrique Luco J. 
Published: June 2021

abstract
The variation with distance of the values of local magnitude, ML, obtained from strong-motion records at short distances to the sources is examined. The available data seem to indicate a gradual decrease with distance from the fault up to a distance of about 20 km followed by a gradual increase for distances in the range from 20 to 100 km. This type of distance dependence can be predicted on the basis of available correlations of peak Wood-Anderson seismograph response with peak velocity and of peak velocity with distance to the fault and local magnitude obtained from actual Wood-Anderson records. These correlations are employed to obtain an alternative relation between local magnitude, synthesized peak Wood-Anderson response and distance to the fault. The alternative relation which is valid only at short distances to the fault gives good agreement with the available data and seems to indicate a degree of saturation of the Wood-Anderson response at short distances. The average estimates of ML based on this alternative relation for several well-recorded events are similar to those obtained on the basis of Richter's standard definition. The alternative estimates have the advantage of removing the distance dependence exhibited by the standard estimates. The effects that this modification of the relation between local magnitude, peak Wood-Anderson response, and distance has on certain estimates of peak strong-motion amplitudes are also examined.
Ground motion values obtained for the 27 July 1980 Sharpsburg, Kentucky, earthquake
Authors: Street R. 
Published: June 2021

abstractFree-field, vector-sum peak particle velocity recordings of the 27 July 1980 Sharpsburg, Kentucky, earthquake result in the following equationslog 10 V R ( 1 Hz ) ( cm/sec ) = − 3.56 + 1.0 m b L g − 1.0 log 1 0 R ( km )andlog 10 V R ( 5 Hz ) ( cm/sec ) = − 3.56 + 1.0 m b L g − 1.0 log 1 0 R ( km )where VR(1 Hz) refers to the resultant vector-sum peak particle velocity at 1 Hz, VR(5 Hz) refers to the resultant vector-sum peak particle velocity at 5 Hz, mbLg is the 1-Hz Lg magnitude commonly used in the Eastern United States, and R is the epicentral distance in kilometers. These equations are intended for the prediction of the maximum particle velocity associated with Lg waves in the Eastern United States in the far-field region of an earthquake, on competent foundation materials.
Measurements of Rayleigh-wave phase velocities in Nevada: Implications for explosion sources and the Massachusetts Mountain earthquake
Authors: Patton H. J. 
Published: June 2021

abstractSingle-station measurements of Rayleigh-wave phase velocity are obtained for paths between the Nevada Test Site and the Livermore broadband regional stations. Nuclear underground explosions detonated in Yucca Valley were the sources of the Rayleigh waves. The source phase φs required by the single-station method is calculated for an explosion source by assuming a spherically symmetric point source with step-function time dependence. The phase velocities are used to analyze the Rayleigh waves of the Massachusetts Mountain earthquake of 5 August 1971. Measured values of source phase for this earthquake are consistent with the focal mechanism determined from P-wave first-motion data (Fischer et al., 1972). A moment-tensor inversion of the Rayleigh-wave spectra for a 3-km-deep source gives a horizontal, least-compressive stress axis oriented N63°W and a seismic moment of 5.5 × 1022 dyne-cm. The general agreement between the results of the P-wave study of Fischer et al. (1972) and this study supports the measurements of phase velocities and, in turn, the explosion source model used to calculate φs.
A discrimination analysis of short-period regional seismic data recorded at Tonto Forest Observatory
Authors: Murphy J. R. , Bennett T. J. 
Published: June 2021

abstractA new seismic discriminant based on spectral differences of regional phases from earthquakes and explosions recorded at a single station has been tested and found to work remarkably well. The test data consisted of a well-constrained set of 30 Nevada Test Site (NTS) explosions and 21 earthquakes located within about 100 km of NTS which were recorded on short-period seismographs at the Tonto Forest Observatory in central Arizona at an epicentral distance averaging 530 km. The events in the data set cover a magnitude range from 3.3 to 4.8 (mb) for which Pn, Pg, and Lg phases have been analyzed.We found that, although Lg phases from earthquakes are typically more prominent than for explosions with comparable P-wave amplitude levels, simple time-domain Lg/P amplitude ratios do not result in a separation of the earthquake and explosion samples consistent enough to provide reliable discrimination. However, spectral analyses of the data over the frequency band from 0.5 to 5.0 Hz revealed significant differences in the spectra of certain regional phases which proved to be a quite reliable discriminant. In particular, both the Pg and Lg spectra from earthquakes have been found to be richer in high-frequency content than corresponding explosion spectra. A discriminant measure, defined as the ratio of average Lg spectral amplitude level in the 0.5- to 1.0-Hz passband to that in the 2.0- to 4.0-Hz passband, provides good separation of earthquake and explosion populations.
Some bounds for seismic risk
Authors: Brillinger David R. 
Published: June 2021

abstract
The seismic risk at a site may be defined as the probability that a given threshold level is exceeded by a chosen variate within a time period of interest, as a result of nearby seismic events. Typically, the probability has been evaluated assuming that the sequence of origin times of earthquakes felt at the site is Poisson. This paper presents bounds for the probability that apply to a general distribution of origin times. In particular, the expected value of a particular counting variate is seen to provide an upper bound for the risk. The results are discussed for some specific marked point processes. Exact expressions for the risk are set down using the conditional intensity function.
Tectonics and recent seismicity near Flathead Lake, Montana
Authors: Qamar Anthony , Kogan Jerry , Stickney Michael C. 
Published: June 2021

abstractSince 1900, more than 290 earthquakes have been reported near Flathead Lake, Montana. Surprisingly, none has exceeded magnitude 5 to 512. Most recent earthquake swarms appear to result from east-west or northwest-southeast extension along short fault segments west and north of the lake. Major normal faults like the Swan and Mission faults east of the lake may pose higher risk, but they appear dormant today. Deformation of sediments in Flathead Lake may be caused by several large earthquakes more than 10,000 years ago but is more probably due to glacial processes accompanying the last retreat of the Cordilleran ice sheet.
Effects of lateral heterogeneity and source process time on the linear moment tensor inversion of long-period Rayleigh waves
Authors: Nakanishi Ichiro , Kanamori Hiroo 
Published: June 2021

abstractSpectra of mantle Rayleigh waves recorded on the IDA network are inverted to determine the seismic moment tensor of the 9 June 1980 California-Mexico Border earthquake, the 29 July 1980 Vanuatu Islands earthquake, and the 9 July 1980 Santa Cruz Islands earthquake. Examinations are made to correct for phase velocity lateral heterogeneity and source process time. A simple regionalization (stable continent, tectonic region, young ocean, and old ocean) improves results of the linear inversion, but the phase correction is not large enough, and the discontinuous change of phase velocity across the boundary between regions causes an artificial rapid change in apparent phase velocity as a function of azimuth. Therefore, a more detailed but gradual representation of the lateral heterogeneity is desirable to correct for the propagation effect in the linear inversion. A source process time which consists of the nondirectional part of the apparent duration of main faulting and the delay time of the faulting from initial break is estimated by a phase analysis of Rayleigh waves. The source process time is generally proportional to the seismic moment on the log-log scale, but some earthquakes deviate considerably from the general relation. Therefore, the measurement of the source process time should be made before the moment tensor inversion. The phase errors introduced by the lateral heterogeneity and source process time may cause a bias to low scalar moment.
Analysis of broadband seismograms from the Chile-eru area
Authors: Kind Rainer , Seidl Dieter 
Published: June 2021

abstractBroadband seismograms, recorded at the Graefenberg (GRF) Array in Germany are analyzed. These data from the Chile-Peru area have often a very complicated signature. We have attempted to identify pP using theoretical seismograms. A third phase besides P and pP, which may have higher frequencies, was discovered in a number of broadband records. Interpretations that relate this phase to the source or the structure are discussed. Our preferred interpretation is an S to P conversion at the bottom of the descending plate.
Pengaruh Loan to Deposit Ratio, Net Profit Margin, dan Dept to Equity Ratio terhadap Profitabilitas (Studi kasus pada Bank Umum Syariah yang terdaftar di Bursa Efek Indonesia periode tahun 2015-2019)
Authors: Margarita Yossi , Kholis Nur 
Published: June 2021

Latar Belakang: Bank bisa dikatakan sebagai tempat transaksi yang berhubungan dengan keuangan misalnya untuk melakukan investasi, pengiriman uang dan tempat mengamankan uang. Otoritas Jasa Keuangan mencatat pertumbuhan aset keuangan syariah di Indonesia terus melaju. Per Januari 2021, total aset keuangan syariah Indonesia (tidak termasuk saham syariah) mencapai Rp1.823,13 triliun. Jumlah tersebut tumbuh 24,54% secara year on year.Tujuan:Tujuan penelitian ini untuk menguji secara empiris dan menganalisis pengaruh Loan to Deposit Ratio (LDR), Net Profit Margin (NPM) dan Dept to Equity Ratio (DER) terhadap profitabilitas pada Bank Umum Syariah di Indonesia. Metode Penelitian Sampel yang digunakan Bank Umum Syariah di Indonesia yaitu Laporan Keuangan Perusahaan Perbankan umum syariah yang terdaftar di BEI periode tahun 2015-2019. Sumber data tersebut diunduh dari web resmi IDX. Menggunakan persamaan regresi linear berganda dan program SPSS 26.Keterbatasan Penelitian : Keterbatasan penelitian ini variabel bebas yang digunakan hanya 3 variabel yaitu (LDR) Loan to Deposit Ratio, (NPM) Net Profit Margin dan (DER) Dept to Equity Ratio. Jumlah sampel 33 selama pengamatan 5 tahun. Keaslian / Novetly Penelitian :Penelitian yang terkait dengan pengaruh NPM, LDR dan DER terhadap profitabilitas terus mengalami perkembangan. Penelitian ini dapat memberikan informasi yang baru tentang perusahaan Perbankan Syariah Indonesia, sejauh mana profitabilitas perusahaan tersebut terukur dengan baik atau tidak.
Comparative evaluation of marginal adaptation of two root end filling materials in root end preparation done with diamond points and ultrasonics - An in vitro SEM study
Authors: Vanti Amulya , Vagarali Hemanth , Patil Chetan 
Published: June 2021

The aim of the present study was to evaluate the marginal adaptation of two bioceramic root end filling materials in root end preparation done with diamond points and ultrasonics under scanning electron microscope.: 56 single rooted extracted human teeth were collected and decoronated to create a standardized length of 14mm and were then endodontically treated. The treated tooth were resected 3mm from the apex at 90 degree angle to long axis of the tooth.The samples were then randomly divided into two groups, group I and group II of 28 samples each. Group I and group II were further divided into subgroup A and subgroup B of 14 samples each. Root end preparations in subgroup A of both the groups were done using ultrasonic tips and in subgroup B of both the groups root end preparations were done using diamond points and In Group I all the root end preparation were filled with MTA(Angelus) and in group II with Biodentine.The apical portions of the roots were then sectioned to obtain 1mm thick transversal sections, scanning electron microscopy was used to determine the adaptations of the root end filling materials with the dentin. Two way Anova and Tukeys Multiple Posthoc test was used for statistical data analysis.: Lowest mean marginal gap of 0.46 micron meter seen with Group II (a) and highest marginal gap of 0.83micron meter seen with Group I (b), which were statistically significant (P&#60;0.05).: Biodentine group, root end preparation done using ultrasonics showed best marginal adaptation than all the other tested groups.
Comparative evaluation of shaping ability of trunatomy and protaper gold files in curved canals using cone?beam computed tomography: An invitro study
Authors: Krutika Kiran Kadam , Hemant Vagarali , Madhu A Pujar , Aishwarya S Tamase , Umesh Sahana 
Published: June 2021

This study aimed to compare the canal transportation and canal centering ability in the preparation of curved root canals after instrumentation with TruNatomy (TN) (TN; Dentsply Sirona, Maillefer, Ballaigues, Switzerland) and ProTaper Gold (PG) (PG; Dentsply, Tulsa Dental Specialties, Tulsa, OK, USA) files using cone‑beam computed tomography (CBCT). 30 Single rooted extracted human teeth with root curvature ranging from 20-30° according to Schneider’s method were selected. Teeth with any visible cracks or fractures, calcifications, previous root canal treatments were excluded. The teeth were randomly assigned into two groups i.e. Group 1-TN and Group 2-PG (n = 15 each). The teeth were instrumented according to manufacturer’s guidelines for both the groups. Canals were scanned using a CBCT scanner before and after preparation to evaluate the transportation and centering ratio at 3 mm, 5 mm, and 7 mm from the apex. The data analysis was done using SPSS software and the test used was independent sample t test for comparison between the 2 groups.Data obtained suggested that TN group presented lesser canal transportation at the middle third of the root. The PG group showed better centering abitily at apical third of the root canal when both the groups were compared. TN resulted in less transportation than PG at the middle third, and PG showed better centering ability at the apical third. Overall, both systems safely prepared root canals, causing minimal errors.
Ophthalmic manifestations of SARS-CoV-2 (COVID-19)
Authors: Garg Aastha , Ramachandra Sandhya 
Published: June 2021

The world has been dealing with the pandemic of COVID-19 since December 2019. The systemic manifestations of the disease are well known. Our study aims to evaluate the ocular manifestations of SARS-CoV-2 (COVID-19). This cross-sectional observational study comprised of 60 subjects that tested positive for COVID-19 by RT-PCR, and admitted to the general wards of a tertiary care hospital of South India. Relevant medical history, ocular history, symptoms, signs and blood investigations data were obtained by communicating directly with the subjects and patient files. Ocular examination was done using diffuse torch light.15% patients presented with conjunctivitis in association with increased conjunctival secretion, tearing and burning sensation. 3.33% patients presented with dry eye disease and orbital cellulitis each. 1.67% patients developed epiphora, cavernous sinus thrombosis and orbital cellulitis with retinal detachment each. A statistically significant correlation was found between the provisional diagnosis and C-reactive protein (CRP) values.Conjunctival congestion can be one of the ocular symptoms of COVID-19. Asymptomatic COVID-19 patients may primarily present to an ophthalmologist with red eye, thus universal precautions must be taken while examining such cases. Evaluation of symptomatic patients with orbital cellulitis and cavernous sinus thrombosis can further aid in understanding the ophthalmic implications, pathogenesis and systemic involvement of this disease.
Evaluation of knowledge, attitude and practice of guidelines towards the novel covid 19 among eye care professionals of a government medical college in north India
Authors: Venugopal Aswathi , Kumar Sunil , Sinha Sony 
Published: June 2021

The novel COVID-19 pandemic, caused by the SARS CoV- 2 virus, has led to widespread public health concerns across the globe. Ophthalmology professionals may be susceptible to infection due to close patient proximity during slit lamp examination and the potential contamination of instruments. The knowledge, attitude, practice (KAP)study can provide an insight of ECPs’(eye care practitioners) knowledge, methods of practice and attitude during this pandemic. This helps to reduce their risk, and that of their family, of contracting the virus, reduce morbidity and mortality associated with being infected.Data and results obtained from this study can also be used to make emergency policies and implement them to stop the spread and impact of a similar outbreak in future.A cross-sectional study was conducted to evaluate the knowledge, attitude and practice of guidelines amongst the Eye care professionals towards the novel Covid-19. The demographic characteristics and infection rate of Covid-19 among the professionals during practice was also recorded and analyzed.In this hospital based cross-sectional study, total 67 eye care professionals including nurses, optometrist participated in the study with their due consent. Among total 67 participants, 60 (89.5%) were doctors, 4 (5.97%) were nurses and 3 (4.477) were optometrists All the participants including doctors, nurses and optometrists achieved a mean of 97.8% in the knowledge section of questionnaire.100% of the participants wear mask and maintain social distancing while all of them have received training regarding practice and management of patients during Covid19 and all the participants have a positive attitude towards the measure taken to combat Covid-19 pandemic.The eye care professionals participated in this study shows a good knowledge, positive attitude and practice of guidelines by the government of India are followed for the pandemic of Covid-19.
Comparative study of optical coherence tomographic analysis of macula in preoperative and postoperative diabetic patients undergoing small incision cataract surgery
Authors: Marati Shruthi , Vallabha K  
Published: June 2021

The clinical evaluation of macular edema has been difficult to characterize, but evaluation has become more precise with the help of optical coherence tomography (OCT). This study is undertaken to evaluate the quantitative changes in macular thickness using spectral domain OCT in diabetic patients undergoing cataract surgery pre and post operatively and its relation with diabetic retinopathy (DR). Study participants included 65 diabetic patients irrespective of presence or absence of retinopathy who underwent cataract surgery. Each eye underwent fundus examination with indirect ophthalmoscopy and OCT of macula i.e.,preoperatively and at postoperatively at day 1, 1 week, 4 weeks and at 12 weeks. Best-corrected visual acuity (BCVA) was recorded at each visit. The central subfield macular thickness (CSMT) increased in all patients irrespective of presence or absence of diabetic retinopathy of about 17.4±25.3µm and 29µm±38.8 at 1 month and 3 month follow up. There was a statistically significant increase seen in CSMT after cataract surgery especially in patients with preoperatively diagnosed macular edema. Associated retinopathy also acts as a risk factor. But there was no statistically significant increase in mild and moderate NPDR preoperatively and also in postoperative period after uncomplicated small incision cataract surgery.
Ocular manifestation in human immunodeficiency virus patients presenting to tertiary eye care centre in rural area
Authors: Mohata Nehal Nareshkumar , Deshmukh Saud Gafur , Pendke Sudhir Sudhakar , Padgilwar Akshay Rajeshwar , Dokhale Sunil Devrao 
Published: June 2021

The ocular manifestations of HIV/AIDS may lead to visual impairment or blindness. The need of hour is an understating of ocular sequelae of HIV infection leading to an early diagnosis of AIDS so that we can start early and effective treatment as per conditions.1. To study the prevalence of ocular manifestations in HIV patients; 2. To study relation of CD4 T Cell count with ocular diseases. The study concluded that HIV/AIDS is a significant cause of ocular disease. Almost around 39% patients having HIV/AIDS have eye disease. HIV Retinopathy is most common in posterior segment and lens involvement is most common in anterior segment manifestations. Usually, early presentation of ocular manifestations in HIV/AIDS patients is asymptomatic or with very less symptoms, which leads to delay in diagnosis and treatment.