bluuebunny/crossref_metadata_2025_split huggingface dataset:
Velocity and attenuation structure of very shallow soils: Evidence for a frequency-dependent Q
Authors: Malagnini Luca 
Published: July 2023

Abstract
The importance of a detailed knowledge of the shear-wave velocity structure in the very shallow depth was recently stressed in strong ground motion studies. In this article, we investigate the 1D velocity and attenuation structure of the very shallow coverage of a sediment-filled valley by using surface waves from a small explosive source, recorded along a 65-m-long linear array. The group and phase velocity dispersion curves are obtained from the analysis of the multi-channel recordings and inverted for the velocity structure. The velocity model obtained in this way is then used as a new starting model for a waveform inversion process, in which both compressional- and shear-wave velocities are iteratively adjusted, obtaining a significative improvement of the fit between data and synthetics.
The Q structure is investigated by using the technique described in Malagnini et al. (1995). The velocity is kept fixed, and the reference frequency for the computation of causal Q is put at 10 Hz, due to the high-frequency content of the recorded waveforms. The resulting Q values in the upper layer (QP = QS = 9 in the first 20 m in depth) are higher than those previously observed at 1 Hz in the same site (QP = QS = 2 in the first 22 m in depth), suggesting, at least in the investigated case, a frequency-dependent attenuation structure for soft-soil coverages.
Earthquake magnitude potential of the Intermountain Seismic Belt, USA, from surface-parameter scaling of late Quaternary faults
Authors: Mason David B. 
Published: July 2023

AbstractTwo of the largest historical earthquakes documented for the United States occurred within the past four decades in a zone of anomalous seismicity in the western interior of the country known as the Intermountain Seismic Belt (ISB). Paleoseismology has revealed the presence of major active faults throughout this region, some of them extending through densely populated area. This study presents mean-value estimates of the maximum earthquake magnitudes that can be expected from 65 of the most prominent late Quaternary fault segments of the ISB using surface rupture parameters. Linear, least-squares regressions of magnitude on surface rupture length, L, maximum surface displacement, D, and DL, respectively, were computed for an updated worldwide set of historical, normal-slip earthquakes. These were compared with similar regressions from other publications, and it was found that a DL-based formula restricted to normal-faulting mechanisms has a relatively high correlation, low standard deviation, and tends to yield magnitudes between those given by D and L alone. This last property is useful for applications to the ISB prehistoric data, where the record of historical, ground-rupturing earthquakes is too sparse to estimate the proportions in which D and L are likely to contribute to seismic energy release of a fault. Application of regressions to published paleoseismic displacements and estimated earthquake segment lengths for the ISB faults shows that D consistently scales a larger magnitude than the corresponding single-segment L by an average of 0.2 to 0.3 magnitude unit, after accounting for bias from the regressions. Considerations of uncertainties in paleoseismic displacements suggest that they cannot fully explain the discrepancy. Since it is known that large earthquakes often encompass multiple segments of a fault, these observations indicate that longer rupture lengths should be used to estimate maximum magnitudes for ISB faults. A dual-segment rupture scenario produces better agreement between D- and L-based magnitudes and is supported by historical and paleoseismic earthquake data from the region. Magnitudes scaled by the DL-based regression for dual-segment rupture range from Ms 6.8 to 7.5 (σm = ± 0.20), and the largest are associated with the central segments of the Wasatch fault and the Swan/Grand Valley, Teton, Madison, and East Bear Lake faults.
Topographic site effects and HVSR. A comparison between observations and theory
Authors: Chávez-García Francisco J. , Sánchez Luis R. , Hatzfeld D. 
Published: July 2023

Abstract
We present a comparison between observed and predicted amplification on a topographic feature. Our data come from an ad hoc experiment carried out during the summer of 1989, in Epire (Northern Greece). Ten digital, autonomous, three-component stations recorded a total of 68 small earthquakes. As these data were inadequate to compute empirical transfer functions using the standard spectral ratio (SSR) technique, we explored the possible use of horizontal-to-vertical spectral ratios (HVSR). First, we compare HVSR computed from theoretical transfer functions for incident P, SV, and Rayleigh waves with the horizontal transfer function for each incidence type. Second, we compute HVSR for our weak-motion data set and show that the results are stable, with a scatter not larger than that usually accepted in SSR studies. We observe significant differences between N-S and E-W motion. When we compare HVSR with theoretical transfer functions, we obtain a better agreement for SV motion than for SH motion. Amplification levels are similar between HVSR and predicted amplification, even for the SH case. This suggests that discrepancies that have been signaled for the topographic amplification between observations and predictions could be due to site effects being present in the reference station used to computed SSR. Our results support the use of HVSR to determine topographic site effects. Thus, HVSR may have a large potential to evaluate site effects in a wider variety of geological conditions than previously thought, without the shortcomings of SSR. Finally, we show that HVSR computed from noise recordings gives a reasonable estimate of HVSR computed from weak-motion data. Although this conclusion should be better substantiated, our preliminary results are encouraging.
Attenuation structure of Coso geothermal area, California, from wave pulse widths
Authors: Wu Huatao , Lees Jonathan M. 
Published: July 2023

Abstract
Pulse width data are used to invert for attenuation structure in the Coso geothermal area, California. The dataset consists of pulse width measurements of 838 microseismic events recorded on a seismic array of 16 downhole stations between August 1993 and March 1994. The quality factor Q correlates well with surface geology and surface heat flow observations. A broad region of low Q (≈ 30 to 37) is located at 0.5 to 1.2 km in depth below Devil's Kitchen, Nicol Prospects, and Coso Hot Springs. A vertical, low Q (≈ 36 in contrast with surrounding rock of 80) region is interpreted as a channel through which hydrothermal energy is transported from depth to the surface. The location of the channel is between stations S1 and S4, and its dimension is about 1 km. At the deep end of the channel, a large, broad body of low Q is also located at 3 km in depth 2 to 4 km to the southwest of Nicol Prospects and Devil's Kitchen. Since it lies at the bottom of the target region and beyond the scope of seismicity, further research is needed to constrain its extent. Numerical modeling with a pseudospectral method is also done to investigate the applicability of the inversion scheme to fractured regions. A linear relationship between pulse width broadening and travel time is upheld, and the proportional constants are estimated.
The Beatty scarp in Nye County, Nevada—An important late quaternary morphologic Datum
Authors: Anderson L. W. , Klinger R. E. 
Published: July 2023

Abstract
The Beatty scarp is a prominent topographic scarp located immediately south of the town of Beatty, Nevada. Early workers interpreted the feature to be a Quaternary fault scarp, but recent studies indicate that the feature is a fluvial scarp marking the former channel margin of the Amargosa River. Detailed topographic scarp profiles indicate that the Beatty scarp is nearly 30 m in height and has maximum scarp-slope angles of 35°. Because the age of the scarp is constrained at about 9000 to 13,000 yr, the Beatty scarp provides an important reference datum for scarp degradation studies and morphologic analyses in southern Nevada.
Analysis of wave propagation in the Valley of Mexico from a dense array of seismometers
Authors: Barker Jeffrey  S. , Campillo Michel , Sánchez-Sesma Francisco  J. , Jongmans Denis , Singh Shri  Krishna 
Published: July 2023

Abstract
A dense array of seismometers was installed and operated in the botanical garden of UNAM within the Valley of Mexico during April and May 1994. The slow surface velocities at the array require an approach to array analysis with the capability of measuring arrival-time differences between stations of less than the sampling interval of the data. Applying the method to principal-component seismograms from earthquakes at local and regional ranges from a number of directions provides the first quantitative information on the composition of the wave-field incident upon Mexico City. Phases that propagate through the entire crust, such as the initial P and Lg waves, cross the array with the expected backazimuth. On the other hand, surface waves in the 2.5- to 5-sec period band, which are sensitive to uppercrustal structure, show systematic rotations of backazimuth. These suggest changes in upper-crustal structure or point scatterers located north and south of Mexico City. For earthquakes outside of the Valley of Mexico, no significant energy was observed propagating across the array from the east (from the lake zone). Thus, although it is clear that seismic waves resonate within the lake zone, little, if any, of this energy is transmitted into the hill zone where the array was located. However, long-duration ground motions are observed at the array, with evidence of multipathing. A back-projection of these late, off-azimuth arrivals indicates that their sources correlate with the boundaries of the Quaternary volcanics of the trans-Mexican volcanic belt.
The central and southern Elsinore fault zone, southern California
Authors: Magistrale Harold , Rockwell Thomas 
Published: July 2023

Abstract
We examine hypocenter patterns, geomorphic features, total slip determinations, and slip-rate information to define the active elements of the southern and central portions of the right-lateral Elsinore fault zone in southern California. In addition to the Elsinore fault, the seismicity patterns define a continuous fault between about 33°N and 33.5°N, 7 to 12 km east of the Elsinore fault, that corresponds to the Aguanga, Agua Tibia, and Earthquake Valley faults. This part of the fault zone is double stranded. Total slip and current slip rate are apparently distributed between the two strands. Slip transfer between the strands occurs at the ends of the eastern strand over two steps with topographic signatures reflecting the step geometries in a right-lateral fault zone: a contractional left step occupied by Palomar mountain, and an extensional right step within the Vallecito-Fish Creek basin. We suggest that the two strands of the double-stranded portion of the fault zone have different ages, and the proportion of slip carried by each strand may have changed through time. Hypocenter patterns define several northeast-striking faults within the fault zone; we attribute a 1940 ML 5.1 earthquake to one of them.
Numerical simulation of multi-parameter seismic scattering
Authors: Chang Hungyu , McMechan George A. 
Published: July 2023

AbstractNumerical simulations using viscoelastic wave equations allow investigation of interactions between the effects of scattering by variations in P velocity, S velocity, density, and intrinsic Q for both P and S waves. When variations are spatially correlated between the parameters in a scattering medium, the amount of scattered energy increases. Thus, neglect of the contribution of any parameter to scattering will result in biased estimates of the contributions by the other parameters; this is especially true if interactions between intrinsic and apparent Q are neglected. The presence of finite intrinsic Q values has two effects; the overall amplitudes of both the incident and scattered waves are attenuated, and new scattering is introduced by the spatial variation of Q. The energy in the coda is reduced substantially and shifted to lower frequencies by attenuation in a viscoelastic medium. For a given scatterer size, the frequency at which the dominant scattering occurs is lower for S waves than for P waves.
Constraints on crustal structure and complex Moho topography beneath Piñon Flat, California, from teleseismic receiver functions
Authors: Eli  Baker G. , Bernard  Minster J. , Zandt George , Gurrola H. 
Published: July 2023

Abstract
We use teleseismic P waves recorded at Piñon Flat Observatory (PFO) to constrain the three-dimensional crustal and upper-mantle velocity structure beneath the station. By forward modeling radial receiver function waveforms, we construct a one-dimensional crustal model that includes a significant shear-velocity inversion at 9 km in depth. Arrivals on the tangential components indicate dip of at least the uppermost discontinuity. Complicated Moho topography, deepening to the northwest of PFO, is suggested by azimuthal dependence of travel times and amplitudes of the receiver functions and travel times of crustal P-wave reverberations. Although fine details cannot be resolved, each of those sets of observations plus mislocation vectors provide strong indications of abrupt Moho topography, possibly including step offsets of several kilometers. This is not only consistent with gravity data in implying Airy isostasy with compensation at Moho depth but extends that model to a much finer length scale than had been resolved.
Ungoverned Spaces and Menace of Herder-Farmer Conflictin Ondo State, South West Nigeria
Authors: Aderayo Adebajo Adeola , Olusola Orebanjo  Abiodun 
Published: July 2023

The study investigated how ungoverned spaces promote herder-farmer conflict in Ondo state, South West, Nigeria. Descriptive research design was adopted for the study. Questionnaire, interview and focus group discussion were used to obtain primary data. Simple random sampling technique was employed in selecting 200 respondents. Eighteen in-depth interviews and two discussions were conducted. Quantitative and qualitative data were analysed using descriptive statistics and content analysis. Findings showed that herders used ungoverned spaces as hideouts to carry out attacks against the communities. Herder-farmer conflict led to loss of lives, destruction of property, disruption of socio-economic activities, food insecurity and distrust among ethnic groups. Amotekun security outfit plays crucial roles in monitoring and checkmating herders who use the unmanned forests as hideouts. Anti-grazing law is effective in restricting the movement of herders causing crop destruction. It recommended that the ungoverned spaces should be used for siting of local industries, tourist centres and mechanised farm settlements in order to create employment opportunities, boost food production and eliminate hideouts for the criminal elements. Drones can be deployed to monitor the operation of herders in the forests. Amotekun security outfit should be trained and adequately equipped with weapons for maximum delivery.
BiblioMetric Analysis in the DevelopMent of Research on Covid-19 Policy in Indonesia in 2020-2022
Authors: SIHALOHO ULFAH OKTARIDA , NURASA HERU , PANCASILAWAN RAMADHAN 
Published: July 2023

This study tries to analyze the bibliographical character and con-tent of covid policy articles published in Scopus indexed journals and written from 2020- 2022. We retrieved data from Scopus Database on July 14, 2022 at 13:50. We use “Covid-19 Policy Indonesia” as a keyword with several categories, namely title, abstract and keywords, filtered by subject area (social science; business, management, and accounting). We only include articles written in English. We processed and analyzed the data using VOS viewer software and co-occurrence visualization of keywords and bibliographies of sources and countries combined. Results: Based on the study protocol, we found 211 documents with the key- word covid policy during 2020-2022. Of the 2 subject areas, social science is the most productive field in publishing covid policy articles. Covid-19 Policy Indonesia has been published in 136 journals. In total, there are 30 countries collaborating to make research related to Covid-19 policies in Indonesia. The Journal of the Review of International Geographical education Online and the Bulletin of Indonesian Economic Studies are the journals that publish the most articles on this topic. Indonesia is the country that publishes the most with 183 articles. From a global perspective, research on covid policies in the 2020 - 2022 range has increased. There are 7 clusters. Indonesia has quite a lot of research related to the Covid-19 Policy in Indonesia, but not many studies have discussed Public Administration. Research themes for covid-19 policies in Indonesia related to Public Administration, Policy Innovation and Collaborative Governance will be interesting to be researched in the future. There is also an opportunity to conduct research on Covid-19 Policy in the context of social science related to public administration.
A clinical study on management of major primary postpartum haemorrhage at tertiary care centre
Authors: Arvindar  , Sen Sangeeta , Khushi  
Published: July 2023

Background: Postpartum Haemorrhage remains one of the leading causes of maternal morbidity and mortality worldwide. It is estimated that about one quarter to one half of preventable maternal deaths are because of haemorrhage. It is defined by the royal college of obstetrician and gynaecologist as blood loss from the genital tract within the first 24 hours after birth of at least 500ml (minor) and at least 1000ml (major) causes of post-partum haemorrhage (PPH) are commonly ascribed to the four Ts (tone, trauma, tissue, 4 thrombin).
Methods: This study aimed to assess the clinical practices used by our hospital in managing major PPH. Observational study of the management of PPH over a period of 2 months from March 2023 to April 2023 was carried out. Criteria examined: history of previous PPH causes of PPH, use of oxytocin in the first stage for more than 6 hours. Role of blood transfusion, presence of senior faculty, and type of uterotonics used.
Results: There were 50 patients diagnosed with major PPH among which 26 had caesarean delivery. Two major risk factors were analysed, one was Use of oxytocin in first stage for more than 6 hours and history of previous PPH. Uterine atony was commonest cause in 64% of cases.
Conclusions: Uterine atony is responsible for most of cases. Early, aggressive, and coordinated intervention by health care professionals is critical in minimizing blood loss to ensure optimal clinical outcomes in management of women with major PPH.
Dermoid cyst indenting bladder: a diagnostic dilemma
Authors: Vashisth Neha , Meena Pragati , Meena Seema , Choudhary Richa 
Published: July 2023

A dermoid cyst is a benign cutaneous developmental anomaly that arises from the entrapment of ectodermal elements along the lines of embryonic closure. These benign tumors are lined by stratified squamous epithelium with mature skin appendages found on their wall and their lumens filled with keratin, hair, teeth etc. They are usually benign in nature. Mature ovarian dermoid cysts are very common accounting for 25% of all benign ovarian neoplasms. Uncomplicated dermoid cysts are usually asymptomatic and easy to diagnose on imaging. Presentation of dermoid cysts are extremely rare in the urinary bladder and it is a diagnostic challenge to the gynecologist, pathologist and urologist. Only few cases are found and documented till now. We present an extremely rare case of dermoid cyst involving bladder in a 29 year old female who presented with chief complaint of pain abdomen associated with passage of hair through the urine since 2 months. Her cystoscopy showed presence of hair and caseous material on the surface of the lesion.
Functional and radiological outcome of distal tibia fractures managed with expert tibia nail: a prospective clinical study
Authors: Arora Kamal K. , Kapila Rajesh , Chaudhary Priti , Singla Rahul , Sanan Lakshay 
Published: July 2023

Leg bone fractures come at the top because it is actively involved in locomotive system with distal tibia fractures having second highest incidence due to its subcutaneous location with very less muscle mass around it. Such fractures are mostly comminuted fractures with extensive soft tissue injuries. These are the fractures which extend within approximately 4 cm. from the tibial plafond. As these fractures occur in proximity of weight bearing surface of ankle joint, a slight maladjustment may lead to permanent disability. Non operative treatment/ open reduction and internal fixation with medial or anterolateral plating of these fractures is associated with multiple post-operative complications like infection, wound dehiscence and non-union. Operative treatment allows proper length and anatomical alignment of the limb, early mobilization and hence excellent final results. The present study of 25 cases was done to evaluate the clinical and radiological functional outcome of extra-articular AO type A simple and compound (Gustilo type I and type II) fractures of distal tibia managed with expert tibial nail and complications (post-operative) if any of patients of either sex, same demographic profile admitted through emergency in a tertiary institute of Punjab. Clinico-radiologically results were assessed using Johner and Wruh’s criteria. Authors got excellent results in 88%, good to fair in 08% of the cases. Expert tibia nail provides good mechanical and rotational stability due to multiple, multidirectional distal locking options available in distal tibia fractures.
Intramyocardial choristoma-a rare entity: first-ever case report and literature review
Authors: Francis Thomas , Kuthubuddeen Muhammad Hilmi , Ranganathan Radhikkhaa , Hamzah M. K. , Arif M. N. M. , Jasid Abdul Muiz 
Published: July 2023

We report the first-ever case of ‘Intramyocardial choristoma’ documented in English-language literature. A 71-year-old woman, during her preoperative echocardiogram assessment, noted to have a large left ventricle (LV) mass with severe mitral regurgitation (MR). The patient was asymptomatic, with CT scan reported a large dense calcified LV mass. She underwent mitral valve replacement with LV mass resection operation. The mass was completely excised. Histopathological examinations show intramyocardial choristoma, with the lesion shows cardiac muscle with areas of calcification and mature bone tissue, with clear margins. Discharged well post operatively. Commonest clinical scenarios for intracardiac masses are myxomas, infective endocarditis with vegetation and thrombus. Primary cardiac tumours are very rare. Choristoma are rare benign tumour, with histologically normal tissues in an abnormal location, with a very rare recurrence rate. Transthoracic echocardiogram is reliable for the evaluation of the intracardiac masses, but the use of contrast echocardiogram gives additional benefit in analysing the characteristics of the intracardiac mass. For complex lesion, such as intramural component, extension into the inflow or outflow and into pericardial/extracardiac, MRI have added benefits. The treatment of choice is complete surgical resection. Follow up surveillance scans are recommended, as there is a very low risk of recurrence with uncertain prognosis. A multidisciplinary team approach is highly recommended in managing the patient pre-operative, intra-operative and post-operatively. Post operatively, regular follow up with imaging is recommended.