bluuebunny/crossref_metadata_2025 huggingface dataset:
Aerobic exercise attenuates the effects of ovariectomy and sedentarism on body composition and food intake in female rats
Authors: FRANCO Frederico Souzalima Caldoncelli , NATALI Antônio José , COSTA Neuza Maria Brunoro
Published: July 2021

ABSTRACT Objective To evaluate the impact of low to moderate aerobic exercise and ovariectomy on body composition and food consumption in female rats. Methods Forty adult Wistar female rats (age: 23 weeks; body weight: 275.2±3.6g; mean±SEM) were divided into 4 groups (n=10): laparotomy-sedentary; laparotomy-exercised; ovariectomy-sedentary; and ovariectomy-exercised. The exercised groups were submitted to a treadmill running program (16m/min; 30min/day, 5 days/week), for 8 weeks. Body weight and food consumption were monitored during the experiment. Visceral fat and carcass water, protein, ash, fat and carbohydrate fractions were analyzed. Two-way ANOVA plus the Tukey’s post hoc test was used for comparisons and p<0.05 was considered significant. Results The ovariectomized (ovariectomy-sedentary+ovariectomy-exercised) and sedentary (laparotomy-sedentary+ovariectomy-sedentary) animals showed higher (p<0.05) weight gain, food consumption, food efficiency ratio and weight gain/body weight ratio than laparotomy animals (laparotomy-sedentary+laparotomy-exercised) and exercised (exercised laparotomy+exercised ovariectomy), respectively. The ovariectomized and sedentary animals showed higher (p<0.05) carcass weight, fat percentage and visceral fat than laparotomy and exercised rats, respectively. Conclusion Ovariectomy and physical inactivity increase obesogenic indicators, whereas regular aerobic exercise of low to moderate intensity attenuates these unfavorable effects in female rats.
FLAME RETARDANTS EFFECTS ON THE INITIAL GROWTH OF Schizolobium amazonicum HUBER EX DUCKE
Authors: Ximenes Elen Silma Oliveira Cruz , Silva Andréa Carvalho da , Souza Adilson Pacheco de , Keffer Josiane Fernandes , Anjos Alison Martins dos , Costa Felipe Gomes
Published: July 2021

ABSTRACT Flame retardants are efficient in fighting wildfire; however, their environmental implications, especially regarding the vegetation, need to be clarified. This work aimed at assessing the effects of flame retardant on the initial growth of Schizolobium amazonicum. Treatments consisted in applying different flame retardant concentrations via substrate and leaf: Phos-Chek WD-881® (0, 3.00, 6.00, 8.00 and 10.00 mL L-1), Hold Fire® (0, 7.00, 9.00, 12.00 and 15.00 mL L-1) and water-retaining polymer Nutrigel® used as alternative retardant (0, 0.25, 0.50, 0.75 and 1.00 g L-1). Growth analyses were carried out to assess the effects of these substances (10 repetitions per treatment). The aliquot of 10.00 mL L-1 of Phos-Chek WD881 applied on the leaves led to an increase of 70% in leaf area and 15% in seedling height. The same Phos-Chek concentration favored height increase (32%) and total dry mass accumulation (33%) throughout time. The concentration of 15 mL L-1 of Hold Fire® applied on leaves, compromised 45% the accumulation of dry biomass in the seedling. Initially, 1.00 g L-1 of Nutrigel® applied via substrate led to an increase of 70% in leaf area, 29% in plant height, and 89% in leaf dry mass. Therefore, Phos-Chek applied on leaves favored shoot growth in S. amazonicum. Hold Fire® applied on leaves impaired biomass accumulation in seedlings. Nutrigel® applied on substrate does not cause long-lasting damage to the initial growth of S. amazonicum. The aliquot of 0.50 g L-1 administered via polymer leave had positive effect on seedling shoot.
IMPACT OF CONVERTING AREAS CULTIVATED WITH SUGARCANE TO EUCALYPT PLANTATIONS ON SOIL QUALITY IN NORTHEASTERN BRAZIL
Authors: Medeiros Aldair de Souza , Ferraz Rener Luciano de Souza , Silva Thamirys Suelle da , Silva Anderson Vitor Lins da , Maia Stoécio Malta Ferreira
Published: July 2021

ABSTRACT Reforestation is considered an effective method to improve soil quality and drain atmospheric CO2 by sequestering carbon, in both soil and vegetation. In this regard, the aim of this study was to evaluate the effects of converting areas cultivated with sugarcane to eucalypt plantations (Eucalyptus spp.) on soil quality and carbon sequestration in a Latossolo (Ferralsol) in the Atlantic Forest region of the Alagoas state, Brazil, through multivariate analysis. The systems under evaluation consisted of four areas: one area cultivated with sugarcane for approximately 20 years, taken as the reference area of this study, and the other three adjacent areas cultivated with eucalypt at 1 (E1), 3 (E3) and 6 (E6) years of age, previously cultivated with sugarcane. Physical (bulk density - BD, Mean weight-diameter - MWD, geometric mean diameter - GMD and aggregate stability index - ASI), chemical (soil organic carbon - SOC, total nitrogen - TN, labile carbon - LC and recalcitrant carbon - RC) and biological (Microbial biomass carbon - MBC, soil carbon respiration - C-CO2 and metabolic quotient - qCO2) properties of soil were evaluated. Data were collected, standardized and submitted to exploratory analysis with principal components. The results show that SOC, LC, TN, GMD, MWD and ASI increased, while BD showed a reduction in E3 and E6 systems. The conversion of sugarcane cultivation with burning of straw and manual harvest into eucalypt plantations was efficient at promoting SOC sequestration and improving physical, chemical and biological properties of soil.
Rural development and the expansion of non‑agricultural activities in the Brazilian Amazon
Authors: Bezerra Francisco Diétima da Silva , Nascimento Carlos Alves do , Maia Alexandre Gori
Published: July 2021

Abstract This paper analyzes the employment and income dynamics of rural families in Brazil's North Region, the main representative of the Brazilian Amazon. We use information from the National Household Sample Survey between 2004 and 2015 to create a typology of families based on the members' occupation in agricultural and non-agricultural activities. We hypothesize that the recent increase in employment and income was strongly associated with non-agricultural activities, reproducing the dynamics observed in other developing countries and Brazil's more developed regions. The results highlight that, differently from the rural exodus observed in the other regions of the country, the number of rural households increased in the North Region, attracted by the expanding non-agricultural occupations. As a result, the importance of earnings from non-agricultural activities and non-labor (pensions, cash transfers, among others) to family income has increased considerably, especially among self-employed family farmers. The final discussion highlights the relevance of non-agricultural activities for public policies to increase income in less developed rural areas.
Vilas e cidades em trânsito: assentamentos urbanos, agência indígena e fronteira colonial na formação do espaço platino (séculos XVI e XVII)
Authors: VILARDAGA JOSÉ CARLOS
Published: July 2021

RESUMO Este texto busca apresentar uma análise, em conjunto, dos assentamentos urbanos coloniais desaparecidos ou trasladados ao longo do primeiro século e meio de colonização da América Meridional, especificamente na região platina, que compreende aqui as jurisdições espanholas do Paraguai, Rio da Prata e Tucumã, e a Capitania de São Vicente, no Brasil. Para além, ou aquém, dos debates sobre ordenamento europeu ou morfologia urbana, a proposta é refletir sobre os assentamentos surgidos nestes espaços de fronteira colonial, marcados pela precariedade, mobilidade e porosidade, e por uma intensa e essencial relação com as populações indígenas contíguas. Busca-se, aqui, sobretudo, entender o papel desses assentamentos na conformação do território colonial platino e na constituição de experiências americanas compartilhadas.
Singing duels and social solidarity
Authors: Frank Roslyn M
Published: July 2021

This is a corrected version of the original draft of the article published originally in 1989
La question des inégalités en matière d’éducation et de santé vue par les institutions internationales: des mots aux mesures
Authors: Pilon Marc , Guillaume Agnès , Bulegon Pilecco Flavia
Published: July 2021

L’éducation et la santé, les deux composantes des services sociaux de base, occupent une place importante dans l’agenda international du développement, notamment depuis l’adoption en 2000 des Objectifs du millénaire pour le développement (OMD), prolongée par celle des Objectifs du développement durable en 2015, au sein desquels la réduction des inégalités constitue une préoccupation majeure. S’est progressivement instituée une véritable gouvernance mondiale, dans laquelle la mesure (au sens de quantification) joue un rôle central à travers la mise en place et le suivi d’une multitude d’indicateurs, notamment en ce qui concerne cette question des inégalités. Les nombreux rapports et textes internationaux produisent des normes internationales qui tendent à s’imposer aux différents acteurs, à devenir « la référence ». À partir de ces documents et supports (rapports mondiaux de suivi de l’éducation pour tous, rapports sur l’État de la santé dans le monde, sites Internet…), l’article interroge à la fois le discours international sur les inégalités et la mesure de celles-ci. En matière d’inégalités, de quoi parle-t-on précisément ? Quels sont les termes employés ? Comment ont-ils évolué au cours du temps ? Enfin, que mesure-t-on réellement  (et ne mesure-t-on pas) ?
Nouvelles technologies de développement et inégalités Nord-Sud
Authors: Al Dahdah Marine
Published: July 2021

Les technologies de l’information et de la communication (TIC) jouent aujourd’hui un rôle de plus en plus central dans les programmes de développement. En 2015, l’organe des Nations Unies chargé des questions de développement et du commerce international, la CNUCED, a rendu public son rapport sur le « développement numérique » et demandé de positionner les TIC au cœur des nouveaux objectifs du développement (UNCTAD 2015). Le positionnement central des TIC dans les programmes internationaux de développement post-2015 est réaffirmé la même année, lors de la définition des « Principes pour le développement numérique » par un groupe d’acteurs issus d’organisations internationales et non gouvernementales. En 2016, le rapport annuel de la Banque mondiale sur le développement dans le monde s’intitule Les Dividendes du numérique et vient confirmer le rôle majeur assigné aux technologies numériques comme levier de développement (World Bank, 2016). Les programmes de santé par téléphone portable – appelés mSanté ou mHealth – sont une forme d’expérimentation de ce développement numérique. À partir de l’exemple d’un dispositif de suivi maternel par téléphone portable déployé au Ghana et en Inde, ce chapitre propose d’explorer un nouveau modèle qui lie le développement économique et social avec l’expansion du téléphone portable et de ses produits. Le recours aux technologies mobiles a introduit dans ces nouveaux programmes de développement des acteurs autrefois étrangers à ce champ et issus en majorité du secteur privé des TIC. Les alliances constituées pour ces programmes se caractérisent par une présence hégémonique d’acteurs privés du Nord, qui financent et déploient des outils techniques en s’appuyant, pour leur mise en œuvre au niveau communautaire, sur les fonctionnaires des services de santé du Sud. La question des rapports Nord-Sud dans les programmes de développement se voit réactualisée à travers ces coopérations technologiques particulières. Ces programmes globaux, encore peu étudiés, constituent une clé de reconfiguration des programmes de développement. En décryptant les inégalités Nord-Sud que ces nouvelles collaborations technologiques impliquent, ce chapitre identifie les logiques hégémoniques qui portent la mSanté.
Appréhender les inégalités dans le cas de sociétés fortement hiérarchisées
Authors: Leservoisier Olivier
Published: July 2021

Ce chapitre propose une série de réflexions sur la manière d’appréhender les inégalités dans un contexte sociétal fortement hiérarchisé et marqué par un pluralisme normatif. Partant du constat que les inégalités ne sont intelligibles que replacées dans des rapports de pouvoir qui leur donnent sens, il s’interroge sur les processus de différenciation sociale et sur les usages sociaux que les acteurs font des situations inégalitaires dans des contextes historiques pluriels et imbriqués. Dans cette perspective, il s’agit non seulement de souligner l’importance de croiser les lectures de la stratification sociale, mais également de réfléchir aux ambivalences que les acteurs entretiennent avec les hiérarchies, à « l’écart entre l’injustice effective et l’injustice perçue », ainsi qu’aux rapports complexes entre mobilités et inégalités. A l’appui de ces réflexions, la présentation d’itinéraires de reconnaissance permet ici de mieux saisir les enjeux de dignité et les rapports ambigus entre normes et valeurs. Elle conduit, par ailleurs, à penser les rapports inégalitaires en termes de continuum, loin de toute vision linéaire et univoque des processus d’émancipation fondée sur le seul modèle d’égalité républicaine.
Mobilité internationale pour études et mobilité sociale: une figure contrastée des inégalités
Authors: Touré Niandou , Gérard Etienne
Published: July 2021

Le champ scolaire malien est caractérisé par de profondes inégalités, notamment entre les différentes catégories d’établissements d’enseignement secondaire. Ces inégalités, au détriment des établissements publics, s’expriment notamment à travers les fortes proportions de bacheliers qui accèdent à l’enseignement supérieur, mais surtout qui poursuivent leurs études supérieures à l’étranger après une scolarité dans des lycées privés, laïcs ou confessionnels. En raison de ces inégalités, les conditions des étudiants de milieu populaire, démunis en capitaux économique et scolaire, sont a priori défavorables à la mobilité. Pourtant, grâce à un ensemble de facteurs favorables, en particulier leur capital social et l’ouverture des systèmes publics d’enseignement supérieur, bon nombre d’entre eux parviennent à réaliser des études à l’étranger, comme au Maroc ou en France. Nos enquêtes montrent que cette mobilité pour études débouche de surcroît, la plupart du temps, sur une mobilité sociale ascendante lorsque ces jeunes, une fois diplômés, retournent dans leur pays à l’issue de leurs études.
Tekstna vezna sredstva u hrvatskom i francuskom znanstvenom diskursu
Authors: Orešković Dvorski Lidija
Published: July 2021

Ova je knjiga posvećena problematici tekstnih veznih sredstava u hrvatskom i francuskom znanstvenome diskursu. Konektori, vezna sredstva na razini teksta, najočitiji su znakovi povezanosti među rečenicama u tekstu, no u toj ulozi nisu usamljeni: interpunkcijski znakovi također su neizostavan dio organizacije teksta, kao i različiti forički elementi. Cilj knjige je prikazati različite teorijske poglede na vezna sredstva te na primjeru znanstvenoga diskursa donijeti pregled najčešćih konektora u hrvatskom i francuskom jeziku. Knjiga je namijenjena svima koji se zanimaju za (nadrečenične) jezične pojave, prije svega studentima diplomskog i doktorskog studija, odnosno mladim istraživačima. Svrsishodnost knjige počiva na malom hrvatsko-francuskom rječniku, odnosno popisima hrvatskih konektora i njihovih francuskih ekvivalenata, koji mogu pronaći svoju praktičnu primjenu među studentima francuskog jezika u pisanju (prvih) akademskih radova.
SAMARA CITY UNDERGROUND URBANIZATION DEVELOPMENT AND ITS CONSEQUENCES
Authors: VASILIEVA Daria I. , BARANOVA Margarita N. , MALTSEV Andrey V. , SOKOLOVA Svetlana V. , SHIMANCHIK Inessa P.
Published: July 2021

Nowadays the area of cities is almost everywhere increasing - the territory urbanization is developing. At the same time, due to lack of land resources, the underground space development intensifi es, and the underground construction volume increases, i.e., underground urbanization takes place. This process has undoubtedly positive results, as it can help solve territorial, transport, environmental and other problems of cities while preserving the unique appearance of buildings in the historical centers of cities. At the same time, some engineering and geological processes may be activated as a negative underground urbanization result. The article deals with underground urbanization history in Samara and defi nes its main stages. More than one million people live in Samara city, subway line was built, there are subway objects of industrial and defense importance (bunkers) reaching considerable depth. Active underground construction can lead to geological processes strengthening (weathering, karst formation, suff osia, etc.), change of strength properties of rocks, violation of natural hydrological regime of the territory. The territory of Samara has an inhomogeneous geological structure and complex engineering and geological construction conditions. Seven engineering-geological districts have been identifi ed and studied, on the territory where underground construction development can lead to diff erent, including negative, consequences.
ARCHITECTURAL AND PLANNING ELEMENTS AS A FACTOR OF URBAN SUSTAINABLE DEVELOPMENT
Authors: GROMILINA Elvira A. , SAMOGOROV Vitaly A.
Published: July 2021

Cities are complex systems consisting of capital objects (architectural objects, transport system and other infrastructural systems), state and non-state institutions, social and economic processes, people (in their various aspects and types of activities), also natural components (topography, hydrography, climate). The article discusses issues related to these specifi c aspects and the relationship between the elements of the architectural and planning structure of the city as a space and a system. Within the framework of the study, a morphological analysis of planning and development was carried out using the example of Samara in the context of sustainable development in order to identify and systematize universal urban elements.
“RESLOBODIZATION” OF CITIES AS AN EFFECTIVE RESPONSE TO THE EPIDEMIOLOGICAL CHALLENGE OF THE CONTEMPORARY. PART II: PRECONDITIONS, ALGORITHMS, RESULTS
Authors: MONASTYRSKAYA Marina Ye.
Published: July 2021

The article (part II) contains the results of studying the features of adaptation of the living environment of the population of the largest city to the vital challenges of the pandemic of the new coronavirus infection COVID-19. The verifi cation of the working hypothesis and the detailing of the main provisions formulated in the fi rst part of the article (see “Urban planning and architecture”. 2021, no. 1) were carried out on the example of an ordinary St. Petersburg locus, actively developed by the townspeople who observed the regimes of self-isolation, partial lifting of strict restrictions and minimal restrictions (2020), which is located within the boundaries of the former sett lement of the Life Guards Semyonovsky regiment, which gave the name to the historical district of the city “Sementsy” and the municipal district “Semyonovsky” (Admiralteisky district of St. Petersburg). In the course of the study, a relationship was established between the immanent properties and parameters of the transformed urban sett lement (territorial- urban-planning, situational-genesis, compositional planning, architectural-spatial, social-functional) and its “anti-epidemiological” potential, realized by the local population and the authorities in the conditions of “pandemic reality” by methods of social self-regulation and centralized management.
METHODS OF ENSURING FUNCTIONAL QUALITY IN ARCHITECTURAL OBJECTS THROUGH TRADITIONAL AND INNOVATIVE TECHNOLOGIES
Authors: PLESHIVTSEV Alexander A.
Published: July 2021

The issues related to the analysis of technological methods for the formation of architectural objects are considered. The purpose of the research is to identify the scale and prospects for the use of traditional and innovative technologies. Solving problems associated with the development of technological methods and processes is accompanied by the development of general theoretical knowledge of architectural science and building materials science as ways to improve the functional quality of architectural systems and their display in the formats of buildings and structures. The real need to develop a systematic approach and the development of a methodology for integrating the technological component (more precisely, non-traditional or innovative methods and techniques) into the algorithm for the formation of architectural objects predetermined and determined the goal and objectives of this study. The theoretical base of research includes both scientifi c and philosophical works devoted to the object and subject of research in a global aspect, and scientifi c and technical literature, in relation to a specifi c area of architectural activity.
A MODERN CITY. LIVING REALITIES OF HISTORY
Authors: DUTSEV Mikhail V.
Published: July 2021

The article is devoted to the reality of the modern historical city in the totality of the actual values of the valuable heritage, traces of the past, mental codes, archetypal images and the memory of civilization. The place of history in today’s socio-cultural fi eld and in the professional context is not clearly defi ned. Together with the understanding of the need to preserve the heritage, traces and memory of the past, there are global trends that mediate the features of the glocal in architecture. However, even this compromise cannot fully demonstrate the complexity of the historical city viability. According to the author, it is necessary to search for reasons that sometimes appear outside the material reality, but address directly to the spiritual world and mental space of a person, which is the main purpose of the article. The emphasis is placed on the artistic dimension of environmental realities, which allows us to determine the living connections of history and modernity on the basis of the author’s concept of artc integration. The article is illustrated by some results of cooperation between the Nizhny Novgorod State University of Architecture and Civil Engineering and the Polytechnic University of Milan (Politecnico di Milano) in the fi eld of reconstruction and renovation of historically valuable territories and author’s photographs.
STUDY OF THE INFLUENCE OF CALCIUM OXIDES IN LIGHT-FUSION RAW MATERIALS ON THE PROPERTIES OF A CERAMIC PRODUCT
Authors: KRASHENINNIKOV Maxim A.
Published: July 2021

One of the main problems of modern building ceramics based on low-melting raw materials is the increased CaO content in the charge. This deviation from the normative values of the technological parameters of production leads to defects - underburning / overburning, quirks, looseness, low strength. Firing mode, molding parameters, addition of additives, preparation of raw materials are the factors for solving this problem. The Alekseevsk low-melting clay and the Yarmysh (Uzbekistan) loess-like loam were investigated, the destruction of the sample structure upon absorption of moisture from the CaO air was graphically modeled, the diagrams of the dependence of the fi ring temperature on the compressive strength were plott ed, the infl uence of molding and the fi neness of grinding of raw materials on the compressive strength and the nature of the formation of ceramic defects was derived.
Crisis Counseling for Black Lives Matter Protests
Authors: Green Darius A. , Williams Brittany A. , Park Kyulee
Published: July 2021

The resurgence of the Black Lives Matter movement in response to the killings of George Floyd, Breonna Taylor, and other Black individuals during the summer of 2020 was accompanied by widespread public demonstration and protest. Despite the peaceful nature of most demonstrations, data indicate that protesters experienced police violence at a disproportionate rate compared to demonstrations associated with other movements. Due to the crisis and unrest that undue police violence toward Black communities can cause, it is imperative that counselors identify ways to support communities in their collective acts toward resistance and liberation. This article reviews how counselors can integrate the Multicultural and Social Justice Counseling Competencies and the American Counseling Association’s Advocacy Competencies into crisis counseling responses that support protesters of the Black Lives Matter movement.
Da atuação da Defensoria Pública na judicialização da saúde: da necessidade de macrocontrole através da revisão judicial do gasto financeiro do ente político
Authors: Ferreira Mendes Leonardo
Published: July 2021

Resumo: Este artigo tem por escopo abordar a atuação da Defensoria Pública na judicialização da saúde, com enfoque na atuação da instituição no controle orçamentário do ente público. Para tanto foi analisada a atuação da Defensoria Pública nas ações individuais e coletivas, foi abordada a possibilidade de atuação da Defensoria Pública no controle de contingenciamentos na orçamentários na área da saúde e, em sequência, foram analisadas duas ações civis públicas que visam referido controle. Por fim, concluiu-se pela necessidade de referida modalidade de controle pela Defensoria Pública no Brasil, notadamente porque é a instituição do sistema de justiça que tem maior contato com a parcela da população usuária do SUS e porque referido controle gera uma maior equidade quando da distribuição de recursos públicos na área de saúde.Palavras-chave: Defensoria Pública, saúde pública, controle financeiro. Abstract: This article intends to discuss the Public Defender's office role in legal claims involving public health, focusing in the public budgetary control. To reach this, the article analyzed the Public Defender work in individual lawsuit and in collective actions, discussing the possibility of the Public Defender to file a lawsuit to control budget contingency of public health and, in sequence, analyzed two collective actions that intend to promote this control. Finally, it has been concluded that this kind of control by Brazilian Public Defender's office is necessary, mainly because it's the institution of justice system that has the major contact with the parcel of population that uses the public health system and because this kind of control grants major equity in the distribution of public health resources.Keywords: Public Defender's office, public health, public finances control.
An analysis of the effects of site geology on the characteristics of near-field Rayleigh waves
Authors: Murphy J. R. , Shah H. K.
Published: July 2021

An approximate analytical model is presented for describing the effects of site geology on the near-field Rayleigh wave ground motions induced by atmospheric explosions. The model is based on an Airy phase approximation to the time domain displacement corresponding to the exact frequency domain solution. Results of numerical simulations are presented which indicate that the amplitude, duration, and dominant frequency of the Rayleigh wave ground motions are strongly dependent on the variation of shear wave velocity with depth at the site. The approximate model is tested over a range of site conditions, and it is demonstrated that the dependence of the Rayleigh wave characteristics on site geology predicted by the more complex, exact model can be accurately described by a remarkably simple set of analytic approximations.
Modeling strong motions produced by earthquakes with two-dimensional numerical codes
Authors: Helmberger Donald V. , Vidale John E.
Published: July 2021

We present a scheme for generating synthetic point-source seismograms for shear dislocation sources using line source (two-dimensional) theory. It is based on expanding the complete three-dimensional solution of the wave equation expressed in cylindrical coordinates in an asymptotic form which provides for the separation of the motions into SH and P-SV systems. We evaluate the equations of motion with the aid of the Cagniard-de Hoop technique and derive close-formed expressions appropriate for finite-difference source excitation.
The foreshock sequence of the 1986 Chalfant, California, earthquake
Authors: Smith Kenneth D. , Priestley Keith F.
Published: July 2021

The ML 6.4 Chalfant, California, earthquake of 21 July 1986 was preceded by an extensive foreshock sequence. Foreshock activity is characterized by shallow clustering activity, including 7 events greater than ML 3, beginning 18 days before the earthquake, an ML 5.7 foreshock 24 hr before the main shock that ruptured only in the upper 10 km of the crust, and an “off-fault” cluster of activity perpendicular to the slip surface of the ML 5.7 foreshock associated with the hypocenter of the main shock. The Chalfant sequence occurred within the local short-period network, and the spatial and temporal development of the foreshock sequence can be observed in detail. Seismicity of the July 1986 time period is largely confined to two nearly conjugate planes; one striking N30°E and dipping 60° to the northwest associated with the ML 5.7 foreshock and the other striking N25°W and dipping 70° to the southwest associated with the main shock. Focal mechanisms for the foreshock period fall into two classes in agreement with these two planes. Shallow clustering of earthquakes in July and the ML 5.7 principal foreshock occur at the intersection of the two planes at a depth of approximately 7 km. The seismic moments determined from inversion of the teleseismic body waves are 4.2 × 1025 and 2.5 × 1025 dyne-cm for the principal foreshock and the main shock, respectively. Slip areas for these two events can be estimated from the aftershock distribution and result in stress drops of 63 bars for the principal foreshock and 16 bars for the main shock. The main shock occurred within an “off-fault” cluster of earthquakes associated with the principal foreshock. This cluster of activity occurs at a predicted local shear stress high in relation to the slip surface of the 20 July earthquake, and this appears to be the triggering mechanism of the main shock. The shallow rupture depth of the principal foreshock indicates that this event was anomalous with respect to the character of main shocks in the region.
High-frequency spectra observed at Anza, California: Implications forQstructure
Authors: Hough S. E. , Anderson J. G.
Published: July 2021

Data from the Anza array in southern California have been analyzed to yield a model for the depth dependence of attenuation. The result is obtained from a formal inversion of the distance dependence of the spectral decay parameter, κ, observed from sources at a wide range of distances from single stations.

The inversion procedure assumes constant Qi in plane layers and finds models which are as nearly constant with depth as possible. We find that the data cannot be explained by a model in which Qi is constant with depth and that the data generally require three-layer models. The resulting models typically give Qi for P waves between 300 and 1000 in the top 5 km, rising to 1000 to 3000 at greater depths, and decreasing to 700 to 1000 around 12 km depth. Qi for S waves is slightly higher in most cases. Because this depth dependence of Qi is generally correlated with the depths of earthquake epicenters, we suggest that Qi may be due to a pressure and temperature-controlled intrinsic attenuation mechanism.
Spectral characteristics of regional phases recorded at Noress
Authors: Suteau-Henson Anne , Bache Thomas C.
Published: July 2021

The spectral characteristics of Pn and Lg are studied for regional events recorded at the NORESS array in Norway. The emphasis is on the potential value of spectral ratios for identifying events as earthquake, chemical explosions, and nuclear explosions. The events studied include a suite of explosions from the Titania Mine in southwest Norway, a suite of events of unknown source type from a site offshore about 90 km from this mine, suites of explosions from several mines in the Soviet Union about 1000 km from NORESS, events from several locations along the 90° azimuth from NORESS, an apparent earthquake in the North Atlantic, and a nuclear explosion (PNE) at a range of 1560 km. The event identification issues addressed are as follows: (1) Can earthquakes and explosions be identified based on the ratio of high- and low-frequency energy in their signal spectra? (2) Do spectral ratios separate mine blasts from earthquakes for all source areas? (3) Will spectral ratio discriminants be effective for identifying decoupled underground nuclear explosions? We conclude that spectral ratios can sometimes separate events. An example is separation of the Titania mine blasts from the events at the nearby offshore locations, although we cannot be sure how much this is due to path differences. However, in general, spectral ratios vary as much within classes of events as they do among different classes. The PNE in our data set allows the simulation of spectra from a decoupled nuclear explosion by simply applying the frequency-dependent decoupling factor to the observed Pn spectrum for this event. After applying a distance correction, the spectrum for this simulated decoupled nuclear explosion is similar to those for the Soviet Union mine blasts in our data set.
Mini-sosie high-resolution reflection survey of the Cottonwood Grove fault in northwestern Tennessee
Authors: Sexton John L. , Jones Paul B.
Published: July 2021

The Cottonwood Grove fault is located within a portion of the New Madrid seismic zone in northwestern Tennessee. Focal mechanism studies indicate that this area is a seismic transition zone. To the southwest is a southwest-northeast seismic trend in which movements along deeper seated faults is predominantly right-lateral strike-slip. To the north is a southeast-northwest seismic trend in which reverse and normal faulting predominate.

The Cottonwood Grove fault is buried beneath the poorly consolidated sediments of the Mississippi embayment. The fault, as identified by an earlier Vibroseis ®* survey is a northeast-southwest trending, eastward-dipping reverse fault with approximately 75 m (245 ft) of displacement on the Paleozoc-Cretaceous boundary.

A Mini-Sosie™† high-resolution seismic reflection survey was conducted through the village of Cottonwood Grove along the previously surveyed Vibroseis line to improve estimates of the age, geometry, and displacements of the Cottonwood Grove fault. Results of the Mini-Sosie survey reveal that displacements across the major fault are relatively consistent within Cretaceous, Paleocene, and middle Eocene sedimentary rocks. In upper Eocene and younger rocks, however, there is no evidence for faulting. Our interpretation includes a previously undetected secondary fault at the boundary between upper Cretaceous and Paleocene rocks. Also included in our interpretation of the subsurface profile through Cottonwood Grove is an Eocene age channel feature located 2 km east of the Cottonwood Grove fault. In addition, the Paleozoic-Cretaceous boundary is interpreted to be an erosional surface with no intrusives included in the Paleozoic rocks. Synthetic seismogram modeling, detailed gravity survey data, and theoretical gravity calculations support this interpretation, and indicate that shallow intrusive bodies within Paleozoic rocks are not needed to explain the observed data. Seismic reflections which would be expected if the intrusives were present are not observed, and the observed Bouguer gravity anomaly can be explained by use of irregularities on the erosional Paleozoic bedrock surface along with sedimentary features within the post-Paleozoic sediments.

These data suggest that Cottonwood Grove fault formed during middle Eocene time and that since that time, any major movement on deeper faults has been predominantly strike-slip with little or no vertical reactivation. This interpretation is consistent with the prevailing hypotheses relating current seismicity of the New Madrid seismic zone to the contemporary regional compressive stress field acting on zones of weakness associated with the Precambrian Reelfoot Rift Complex.

®* Registered trademark of Conoco, Inc. ™† Registered trademark of Société Nationale Elf Aquitane (Production).
Stochastic geologic effects on near-field ground motions in alluvium
Authors: Reinke Robert E. , Stump Brian W.
Published: July 2021

Analysis of accelerograms recorded at the 20 m range from a buried 5-lb detonation in alluvium revealed wide (as large as 20 dB in the amplitude modulus of the Fourier transform) variations in response for frequencies above 35 Hz. Additional experiments were performed which ruled out source asymmetry or instrumental irregularity as the cause of these variations. The observations suggest that scattering by geologic inhomogeneity is responsible for the frequency-dependent spatial variability in ground motion. A thorough understanding of the physical processes responsible for this variability requires that a quantitative relationship be established between the subsurface material property information and the observed ground motion characteristics. An attempt was made to do this using available standard penetration test data from the test bed where the initial experiment was detonated. Autocorrelations of the blow count data from the standard penetration test were computed and compared with theoretical exponential and Gaussian distributions. The exponential distribution with a scale length between 2.0 and 3.0 m best matches the data. Assuming the Born approximation, a scale length of 2.0 to 3.0 m implies that significant scattering should occur above 10 Hz. The recorded ground motions are, however, coherent out to about 35 Hz, suggesting a scale length on the order of 0.5 to 1.0 m, which is beyond the resolution of the standard penetration test technique. This scale length is, however, not unreasonable in light of the general geologic characteristics of the test area.
Experimental confirmation of superposition from small-scale explosions
Authors: Stump Brian W. , Reinke Robert E.
Published: July 2021

An in situ experimental program in alluvium is implemented and analyzed to test linear superposition. After separating stochastic and deterministic propagation path effects, direct superposition is experimentally validated at 20 m for two 5-lb charges spaced as close as 2 m in alluvium. The charges are separated by the scaled range of 147 m/kt1/3 and observed at the scaled range of 1470 m/kt1/3. Finite-spatial source effects are observed and simulated in the plane passing through two charges separated by 2 to 10 m. The deterministic single-burst waveforms are used to model the multiple-burst data. The effects observed and simulated include direct superposition below the corner frequency, shift to lower corner frequency with increasing charge separation, and spectral scalloping. For charges closely spaced (up to 4 m, observed at 20 and 24 m), the primary effect on the waveform is replicated by a constant delay time between two identical waveforms. For charges spaced by 10 m (observed at 20 and 30 m), the effects of propagation path differences must be included. These effects result in smoothed spectra.
Comments on the joint determination of hypocenters and station corrections
Authors: Pujol Jose
Published: July 2021

Some aspects of the joint determination of hypocenters and station corrections (JHD) are discussed. An alternative solution to one of the methods currently in use (Pavlis and Booker, 1983) is proposed. It requires only a modest computational effort and is very fast. This simplification is not achieved at the expense of numerical stability and is backed by a theoretical study of the properties of the matrices involved. These matrices are positive semidefinite, and this allows a general analysis of the JHD solution. Several facts, some of them known and some new, are formally proved. It is possible, for example, to carry out a detailed study of the eigenvalues of the matrix from which the station corrections are derived. It is also shown that the mean value of the initial estimate of station corrections are retained as a bias in the final solution. The relationship between the approximate solution of Frohlich (1979) and the exact JHD solution can also be studied, and the reason for its success in certain cases is explained.
A fast, two-point, three-dimensional raytracing algorithm using a simple step search method
Authors: Prothero W. A. , Taylor W. J. , Eickemeyer J. A.
Published: July 2021

The simplex method of function minimization is used to find the ray that follows the path of minimum time through an arbitrary three-dimensionally varying medium. The advantage of this method is that it is extremely fast, always converges, and lends itself to a variety of velocity parameterizations. The first step in the algorithm is to find the minimum time circular arc path between the source and receiver using an exhaustive search method. Then perturbations, consisting of a sum of N sine wave harmonics with their zero crossings at the endpoints, are made to the circular arc path. The simplex method searches for the amplitude coefficients that produce the path of least time. On a VAX-750 running the VMS operating system, the first arriving ray for a station receiver distance of 96 km is computed to an accuracy of 0.02 sec, computed in a southern California velocity structure using less than 26 sec of computer time. The required computer time decreases as the ray path distance decreases.
Reduced seismic velocities in the source zone of New Madrid earthquakes
Authors: Al-Shukri Haydar J. , Mitchell Brian J.
Published: July 2021

A three-dimensional inversion of P-wave travel-time residuals from local earthquakes reveals a remarkable pattern of low seismic velocities in crustal rocks immediately adjacent to the active portions of the New Madrid fault system. Seismic velocities are lowest in regions of greatest concentration of earthquake activity near two intersections of linear trends in seismicity. The maximum reduction in compressional wave velocity is at least 7 per cent in the upper 5 km of the crust and at least 4 per cent in the depth range of 5 to 14 km. The reductions are consistent with a velocity decrease which would be expected if crustal rocks in the source zone contain fluid-filled cracks in which pore pressure is a substantial fraction of external pressure. The presence or absence of such fluids may explain why some portions of the faults in and surrounding the upper Mississippi Embayment are active while others are not.
Alarm systems based on a pair of short-term earthquake precursors
Authors: Grandori Giuseppe , Guagenti Elisa , Perotti Federico
Published: July 2021

A statistical analysis of the foreshock-main shock correlation for a seismically active region in Italy is presented. It is found that the probability that a weak shock be followed within 2 days by a main shock is of the order of 2 per cent, while the probability that a main shock be preceded by a foreshock is of the order of 50 per cent. These results are quite similar to those found by L. Jones (1985) for southern California.

The effectiveness of alarm systems based on a pair of short-term earthquake precursors is then analyzed. In particular, the analysis shows under what conditions the precursor, consisting of potential foreshocks, could be combined with another precursor to provide a reasonably effective alarm system.
Studies of high-frequency seismic noise in eastern Kazakhstan
Authors: Berger J. , Eissler H. K. , Vernon F. L. , Nersesov I. L. , Gokhberg M. B. , Stolyrov O. A. , Tarasov N. T.
Published: July 2021

Three seismographic stations have been established in the region of the principal underground nuclear weapons test site in the republic of Kazakhstan in the Soviet Union. Instrumentation includes both surface and borehole seismometers with a bandwidth of 100 Hz and a system dynamic range of 180 dB. Power spectra of the regional ambient ground acceleration peak between 4 and 6 Hz, and are, on average, frequency independent above 10 Hz, where levels are approximately equal to 10−15 to 10−16 (m sec−2)2Hz−1. Kazakh noise levels are roughly equivalent to those observed by the Regional Seismic Test Network between 1 and 20 Hz, and about 10 to 20 dB higher than the very low noise model for Lajitas, Texas, in the same band. Noise observed by the borehole sensors is about 10 dB less than that observed by the surface instruments above about 20 Hz under low wind conditions at two of the three Kazakh sites; borehole improvement is greater under high winds. The third Kazakh site, Karasu, is characterized by much higher surface noise levels (15 to 20 dB higher than the borehole levels from 4 to 40 Hz) under both low or high wind conditions, which is attributed to amplification by local site conditions and the exposed terrain. Power spectra of individual runs of ambient vertical ground acceleration measured down the borehole show that high-frequency slopes (between 10 and 80 Hz) vary between f−0.60 and f0.22, depending on wind and site conditions.
Application of Nuttli's method to estimate yield of Nevada Test Site explosions recorded on Lawrence Livermore National Laboratory's Digital Seismic System
Authors: Patton H. J.
Published: July 2021

Methods utilizing Lg waves for estimating yields of underground nuclear explosions have attracted considerable attention for their accuracy, claims of portability, and suitability for low yield test ban verification. In this study, the method developed by Nuttli is applied to a large dataset of Nevada Test Site explosions recorded on Livermore's Digital Seismic System. The purpose was to check the reproducibility of Nuttli's results and to verify the accuracy of mb(Lg) to estimate yield at high and low yield levels. Portability of the method is examined from the perspective of variability of the magnitude-yield relations as a function of station site and source geology. The results of this study show accuracies of about a factor of 1.6 in yield at the two sigma level for shots below the water table in source regions exhibiting more or less uniform coupling. At Nevada Test Site, there are three such source regions: Pahute Mesa (areas 19 and 20), northern Yucca including areas 2 and 9, and southern Yucca including areas 3, 4, and 7. There is no apparent degradation in accuracies at low yields (1 to 10 kt). Variations in source coupling were observed as a function of shot location and as a function of the medium's gas porosity for shots in tuff. The effect of gas porosity was not observed for shots in alluvium, which have uniformly low coupling compared to shots in tuff. Variations in magnitude-yield relations were observed from station to station, while the four-station network-average magnitudes are more robust and agreed well with Nuttli's magnitude-yield relations. Thus, portability to other test sites should be considered guardedly optimistic, requiring geologic and seismic data related to coupling in each source region and sufficient numbers of stations (four or five) to estimate a robust network magnitude. Taken all together, the findings of this study lend support to this method as a viable means of monitoring a threshold test ban or low yield threshold test ban.