bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of different monitoring methods of surface cleanliness in operating rooms
Authors: Nascimento Elaine Aparecida da Silva , Poveda Vanessa de Brito , Monteiro Jussimara
Published: July 2021

ABSTRACT Objectives: to evaluate different monitoring methods for detecting the presence of organic or biological matter before and after the cleaning and disinfection processes of the operating room. Methods: this is a cross-sectional study based on visual inspection, adenosine triphosphate levels and microbiological culture for the assessment of cleaning and disinfection. Results: 93.3% of the surfaces inspected visually for this study purpose were considered clean, even when high levels of adenosine triphosphate and microbiological analysis detected presence of microorganisms relevant to biofilm formation. Conclusions: the cleaning and disinfection processes reduced the microbial load and organic matter of the inspected surfaces, demonstrated by the values obtained by the adenosine triphosphate bioluminescence assay and microbiological analysis, but the visual inspection as a unique tool to assess the surfaces’ cleanliness may give a false impression of clean environment.
Dinheiro e sucesso eleitoral em 2008, 2012 e 2016 no Brasil
Authors: Deschamps Jacques Paul , Junckes Ivan Jairo , Horochovski Rodrigo Rossi , Camargo Neilor Fermino
Published: July 2021

Resumo A intimidade entre dinheiro e voto tem sido exposta nas democracias contemporâneas por meio de sua influência nos resultados eleitorais e na produção de políticas públicas. Estudos apontam que a progressiva iniquidade entre os recursos financeiros dos candidatos nas eleições abala a democracia e promove a plutocracia, ou seja, amplia o domínio oligárquico dos processos políticos pelos cidadãos e pelos grupos mais ricos. Contribuindo para esse debate, o presente trabalho analisa a relação entre receitas de financiamento e o desempenho e o sucesso eleitoral de 317.107 candidaturas a vereador nas eleições de 2008, 2012 e 2016, em 441 municípios brasileiros com mais de 50 mil eleitores. Trata-se de um estudo inédito em sua abrangência temporal, que permite suprir uma carência de exames sobre eleições subnacionais, em especial nas disputas ao Legislativo municipal. Os dados utilizados têm origem no Tribunal Superior Eleitoral, nas tabelas de candidaturas, nos resultados e na prestação de contas. Os testes e as análises de dados e informações utilizam recursos estatísticos de correlação e regressão, além de medidas centrais e razão de chances. Os resultados permitem confirmar uma forte associação entre dinheiro, voto e sucesso eleitoral, inclusive no pleito de 2016, quando estiveram proibidas as doações empresariais. A manutenção de um padrão, tanto temporal quanto geográfico, indica a existência de características estruturais de caráter plutocrático no financiamento eleitoral dos candidatos a vereador nas cidades pesquisadas e, consequentemente, sobre a produção de políticas públicas no Brasil.
MODELOS DE PROFESSOR E ALUNO SUSTENTADOS EM DOCUMENTOS OFICIAIS: DOS PCNS À BNCC
Authors: GALIAN CLÁUDIA VALENTINA ASSUMPÇÃO , PIETRI ÉMERSON DE , SASSERON LÚCIA HELENA
Published: July 2021

RESUMO: Neste trabalho são apresentados resultados de pesquisa orientada pelo objetivo de conhecer os efeitos do discurso regulador sobre a recontextualização pedagógica de conhecimentos na elaboração de diretrizes curriculares oficiais. Com base em princípios de análise discursiva, caracterizam-se as permanências e mudanças expressas na Base Nacional Comum Curricular (BRASIL, 2017) em relação às concepções de ensino e de aprendizagem que fundamentaram anteriormente propostas curriculares no país, materializadas nos Parâmetros Curriculares Nacionais (BRASIL, 1997). A análise pauta-se na leitura e discussão de trechos destes dois documentos, com foco na caracterização de papéis que parecem ser atribuídos a professores e a estudantes. Os resultados evidenciam o reposicionamento, de um contexto histórico a outro, das funções projetadas para docentes e discentes nos processos de ensino e aprendizagem, de modo a desconsiderar-se a agentividade e a implicação dos sujeitos do trabalho pedagógico, reduzindo-se a relação didática à apropriação de um conjunto pré-estabelecido de conhecimentos. Embora não tenha sido a intenção do presente estudo, entendemos que esta investigação e seus resultados trazem contribuições às discussões sobre as normativas que passam a entrar em vigência em relação à formação de professores e também sobre a função da escola na formação de estudantes.
Combined selection for adaptability, genotypic stability and cowpea yield from mixed models
Authors: Cruz Derivaldo Pureza da , Gravina Geraldo de Amaral , Vivas Marcelo , Entringer Geovana Cremonini , Souza Yure Pequeno de , Rocha Richardson Sales , Jaeggi Mário Euclides Pechara da Costa , Albuquerque Dalcirlei Pinheiro , Amaral Junior Antônio Teixeira do , Gravina Lília Marques , Rocha Maurisrael de Moura , Silva Rita de Kássia Guarnier da
Published: July 2021

ABSTRACT: The potential expression of crop productivity is a constant challenge for plant breeders in the face of oscillations in environmental variables, making selection difficult and increasing the operational and methodological costs in obtaining the ideal cultivar for a determined region. The objective of the research was to investigate the effects of genotype x environment interaction in the selection of cowpea lines with high grain yield, adaptability, and genotypic stability simultaneously, in environments of the Northwest region of Rio de Janeiro State, using mixed models (Maximum Restricted Likelihood - REML/Best Linear Unbiased Prediction - BLUP). 27 cowpea genotypes were evaluated in six environments by combining location (Cambuci-RJ and Bom Jesus do Itabapoana-RJ) and year (2016, 2017 and 2018). A randomized block design with four replications was performed. The genetic parameters were estimated via the REML/BLUP procedure, and the selection was based on the harmonic mean method of the relative performance of the genetic values (HMRPGV). A meaningful difference was observed for environment and genotype x environment interaction. The residual variance and the variance of the genotype x environment interaction formed the most significant fractions of the phenotypic variance. Lines 4 (Bico-de-ouro 1-5-24), 6 (Pingo-de-Ouro 1-5-4), 5 (Pingo-de-Ouro 1-5-26), and 9 (Pingo-de-Ouro 1-5-8), stood out as superior in terms of stability and adaptability and grain yield by HMRPGV. Commercial cultivars 13 (BRS-Tumucumaque) and 26 (BRS-Itaim) had high grain yield, adaptability, and specific stability in the evaluated edaphoclimatic conditions.
Cash transfer and female labor supply: evidence from Brazil’s rural area
Authors: Lima Fulvia Fernanda , Duarte Gisléia Benini
Published: July 2021

Abstract This paper analyzed the relationship between Bolsa Família Program (BFP) and labor supply of women in rural areas from Brazil, using the Propensity Score Matching (with the nearest-neighbor, kernel, and IPW criteria), Ordinary Least Squares on the treatment (beneficiaries), and control (non-beneficiaries) groups with the robustness analysis proposed by Oster (2015). The results showed that the BFP has an opposite effect to the one pronounced in the critiques of the program, the beneficiaries did not have more or fewer work hours than the non-beneficiaries, this fact can be explained by the value of the benefit not being able to meet the expenses of the household. From these results, we can conclude that both tests reinforce the importance of continuing the investigation of the effects on female labor supply in the rural environment in the light of different guidelines.
Análise de cenários do agronegócio brasileiro frente à China, aos EUA e à UE, utilizando um modelo de equilíbrio geral computável
Authors: Buchmann Jurandir Luiz , Massuquetti Angélica , Azevedo André Filipe Zago de
Published: July 2021

Resumo O objetivo do estudo é analisar as oportunidades de comércio a partir da simulação de uma possível integração comercial do Brasil com a China, com os EUA e com a UE, buscando identificar os setores mais beneficiados pelo eventual acordo, classificados conforme seu grau de intensidade tecnológica, com ênfase no agronegócio brasileiro. Empregou-se a classificação de produtos por grau de intensidade tecnológica segundo os critérios da Organização para Cooperação e Desenvolvimento Econômico (OCDE) e foi utilizado o modelo de equilíbrio geral computável, mediante uso da base de dados Global Trade Analysis Project (GTAP), versão 9, para simular os impactos sobre o comércio internacional e os efeitos sobre o bem-estar de uma possível integração comercial do Brasil com os parceiros selecionados. Por fim, os resultados obtidos mostram que os ganhos de bem-estar para o Brasil, em todos os acordos, estão principalmente vinculados à melhor alocação dos seus recursos produtivos, que estariam concentrados basicamente nos setores primários e de baixa intensidade tecnológica, que agregaria o agronegócio.
Panorama da agricultura orgânica e dos agrotóxicos no Brasil: uma análise a partir dos censos 2006 e 2017
Authors: Mattei Taíse Fátima , Michellon Ednaldo
Published: July 2021

Resumo Frente ao debate relativamente antigo sobre o uso de agrotóxicos e práticas agrícolas mais sustentáveis, este artigo se propõe a fazer um panorama da agricultura orgânica e do uso de agrotóxicos no Brasil, a partir dos Censos Agropecuários de 2006 e 2017. A pesquisa se caracterizou como comparativa descritiva e focou a análise nos estabelecimentos agropecuários. Os principais resultados indicaram que, em 2006, cerca de 27% dos estabelecimentos agropecuários usavam agrotóxicos; já em 2017, esse percentual subiu para 33%. As regiões líderes em estabelecimentos com uso de agrotóxicos em 2006 e 2017 eram Sul e Nordeste. Os estados Rio Grande do Sul e Paraná eram os estados onde se encontravam o maior número de estabelecimentos produzindo com agrotóxicos do total brasileiro, nos dois Censos analisados. Com relação à agricultura orgânica, percebeu-se que houve uma redução relativa do número de estabelecimentos com agricultura orgânica no Brasil nesse período, embora seja preciso fazer ressalvas quanto à possibilidade de superestimação das informações. Em 2006, estavam, na região Nordeste, 46,7% desses estabelecimentos, 21% na região Sul e 20% na região Sudeste. Já em 2017, 28% estavam na região Sudeste, 27% na região Nordeste e 20% na região Sul.
O impacto do crédito rural no produto agropecuário brasileiro
Authors: Borges Murilo José , Parré José Luiz
Published: July 2021

Resumo: O trabalho avalia a relação existente entre crédito rural e produto agropecuário nos anos de 1999 a 2018. Utilizando-se da metodologia de Vetores Autorregressivos, causalidade de Granger e o método dos mínimos quadrados ordinários e generalizados, foram estimados tanto os impactos expressos via elasticidades quanto à relação ótima decorrentes desta relação. Ao longo do período analisado, observou-se significativo aumento real do crédito rural, porém tal ampliação ficou limitada a um menor número de estabelecimentos rurais e a contratos com valores mais elevados. A despeito do ambiente de racionamento de crédito rural existente no país, conclui-se que o impacto do crédito rural total sobre o produto agropecuário foi de 0,20%. Quanto aos testes de causalidade de Granger, os resultados indicam que há precedência temporal do crédito rural ao produto agropecuário e, portanto, de forma unidirecional, o crédito rural causa, no sentido de Granger, PIB agropecuário. Por fim, quanto à relação ótima entre produto agropecuário e crédito rural, o valor estimado de crédito rural que maximiza o produto agropecuário foi de, aproximadamente, R$ 58 bilhões ao trimestre.
Cadena Láctea Argentina: Un análisis estructural de derivación de demandas intermedias para la obtención de las elasticidades
Authors: Vicentin Masaro Jimena
Published: July 2021

Resumen: Atendiendo a la importancia de la cadena productiva láctea en la economía argentina, se realiza análisis estructural de la misma derivando las demandas intermedias para conocer las elasticidades. A partir de un estricto planteamiento teórico de la cadena y las relaciones entre los diferentes niveles que lo componen y, utilizando un modelo de ecuaciones simultáneas, se cuantifican las relaciones de precios y cantidades a cada nivel para evaluar los efectos de posibles cambios en las variables claves de ésta cadena productiva, entre ellos de los precios. Se utiliza información secundaria, y se estima el modelo mediante mínimos cuadrados en tres etapas. Como resultados se destaca la inelasticidad de la oferta y demanda de todos los niveles respecto a sus propios precios, y mayor sensibilidad al precio mayorista. De las variables de política, solo los impuestos a las exportaciones resultan significativas. Cabe mencionar que si bien la no incorporación de stocks y la utilización de datos agregados es una limitación del presente, el aporte fundamental radica en el diseño integral de la cadena argentina con el tratamiento simultáneo de la determinación de las cantidades y precios, permitiendo conocer las relaciones a lo largo de dicha cadena de modo integral.
O papel dos “bairros rurais” na consolidação do território bragantino
Authors: NUNES CAROLINA GONÇALVES , SALGADO IVONE
Published: July 2021

RESUMO Este trabalho discute a formação dos “bairros rurais” de Bragança Paulista utilizando as modificações na economia local ao longo do tempo como um dos principais elementos explicativos para o avanço da ocupação territorial da freguesia/vila. Procuramos reconstituir o processo de ocupação territorial de Bragança acompanhando a distribuição de sesmarias, número de fogos, número de habitantes, localização geográfica e desenvolvimento dos “bairros rurais” que se formaram. Foi adotada uma metodologia que se insere num conjunto de estudos sobre o processo de urbanização no Brasil que utilizam o método de leitura da paisagem e da cultura material e que procuram analisar dinâmicas e lógicas de enraizamento da população no território. O foco da análise foi a formação de “bairros rurais” em Bragança e sua decisiva influência na consolidação da localidade, de forma que foi possível perceber seu papel no fortalecimento de uma rede de abastecimento das Minas Gerais e da capital de São Paulo nos séculos XVIII e XIX além do processo de formação da microrrede urbana regional. Utilizou-se documentação cartográfica e documentação primária diversa, em especial de caráter censitário, com destaque para as listas nominativas e documentos manuscritos (a princípio anuais) que contêm a relação nominal dos habitantes de diversos municípios da capitania/província de São Paulo, nos quais são descritos por fogos (unidades domiciliares/produtivas) algumas características relacionadas aos moradores, como estado conjugal e idade, entre outras.
O ensino sobre a Lua e suas fases: uma proposta observacional para os Anos Iniciais do Ensino Fundamental
Authors: Gonçalves Paula Cristina da Silva , Bretones Paulo Sergio
Published: July 2021

Resumo: Este artigo expõe os resultados de uma pesquisa experimental sobre o ensino de Lua e suas fases, desenvolvida em uma turma de segundo ano do Ensino Fundamental, em uma escola pública. A investigação busca verificar o processo de aprendizagem tendo a observação do astro no céu pelos estudantes como base principal, utilizando o desenho como forma de registro e rodas de conversa, ambos acessíveis às crianças pequenas. Nosso objetivo é verificar quais questões e ideias emergem quando a observação está no cerne do processo e o que os estudantes demonstram compreender a partir dessa escolha metodológica, tendo em vista a formação dos conceitos científicos de Vigotski para crianças. A pesquisa evidencia o aprendizado dos discentes a respeito dos movimentos observáveis da Lua ao longo das noites, de sua mudança de aspecto, entre outras características.
Sentidos da Cultura em suas Relações com a Religião:Políticas Culturais e Diversidade Religiosa no Brasil
Authors: Giumbelli Emerson
Published: July 2021

RESUMO Que sentidos assume a noção de cultura em políticas públicas que implicam agentes religiosos no Brasil? Apresentar respostas para tal pergunta é o objetivo deste artigo. Para tanto, analisam-se três áreas nas quais ocorrem investimentos estatais relacionados à “cultura” que incidem sobre universos religiosos: projetos que buscam recursos por meio da assim chamada Lei Rouanet; projetos contemplados como Pontos de Cultura; e projetos que visam o fortalecimento do turismo cultural relacionado à religião. Com a utilização de estatísticas e o emprego de narrativas etnográficas, o texto analisa o modo como se concebe e se apropria a categoria “cultura” considerando os pressupostos das políticas públicas abordadas e as configurações assumidas por situações concretas. O pano de fundo para a análise são discussões acerca da objetificação da noção de cultura, que tem se tornado parte de vernáculos sociais e tem se vinculado a demandas por direitos ou se envolvido em amplos conflitos de interpretação. As conclusões salientam a relação dos vários sentidos assumidos por essa noção com quadros mais ou menos pluralistas acerca da diversidade religiosa no Brasil atual.
Greening the school for sustainable development: a case of Tshwane North District
Authors: BOPAPE Johannah , MUDAU Awelani V , MSEZANE Sıkhulıle Bongınkosı
Published: July 2021

The aim of the study was to answer the question that arises about what knowledge do role players have about sustainable development through greening schools. The research employed qualitative multiple case study design in three purposefully sampled schools at Tshwane North District, Gauteng Province of South Africa. Besides literature review and theoretical framework of sources, the data was collected through focus group interviews, direct observation and document analysis. Data collected was analysed with thematic content analysis. The results revealed that school role players have little knowledge on greening schools to ensure sustainable development; and opportunities and threats need to be addressed by role players. These were attributed by lack of policy framework and capacity building on how greening schools should be implemented. The study recommended creation of an integrative assessment of green schools that embraces practical activity plan on curriculum and infrastructure. Further research studies in the area of greening schools are recommended for effective sustainable development on school resources.
AN UPDATED METHOD FOR HEATING CALCULATING IN BUILDINGS WITH INTERMITTENT HEATING
Authors: VYTCHIKOV Yuri S. , CHULKOV Alexander A. , GOLIKOV Vladislav A.
Published: July 2021

An updated method of heating calculation of buildings operated in the conditions of intermitt ent heating is considered. On the basis of the conducted studies, analytical dependences were obtained for determining energy consumption during heating of building enclosing structures, taking into account the infl uence of the order of location of thermal insulation and structural layers, as well as temperature changes during heating of each layer. Formulas for fi nding the change in the temperature of the internal air during the heating of the premises and the internal surface of the enclosing structures are obtained. On the basis of the proposed refi ned methodology, the calculation of the heating of the living room of a country cott age located on the territory of the Samara region was performed.
THE RESEARCH THE INFILTRATION EFFECT OF OUTSIDE AIR ON THE VALUE OF AIR EXCHANGE IN LOW-RISE RESIDENTIAL BUILDINGS
Authors: KOSTUGANOV Arman B.
Published: July 2021

This article presents the results of a theoretical study of the infl uence the outside air infi ltration through the enclosing structures of the walls on the amount the air’s exchange in low-rise residential buildings. Based on the information analysis from offi cial documents of state statistical and analytical bodies, the most frequently used external wall structures in modern low-rise residential construction have been determined. Based on the provisions analysis of modern regulatory documents in the construction’s fi eld, the minimum values the required air exchange were determined and the calculations of the values the infi ltration air fl ow through the outer walls for various premises of low-rise residential buildings were made. Based on the results of the analysis and calculations was made a generalizing conclusion that for the considered premises of modern low-rise residential buildings, at the expense of the infi ltration of outside air through the enclosing structures of the walls, it is impossible to provide even 20 % of the minimum air exchange.
PROMISING METHODS FOR BIOLOGICAL REMOVAL OF PHOSPHATES FROM WASTEWATER
Authors: TEPLYH Svetlana Yu , BOCHKOV Dmitrii S. , BAZAROVA Anastasya O.
Published: July 2021

The article compares the removal of phosphates from wastewater by promising biological methods, namely biotechnologies based on the use of phosphate-accumulating organisms. The microbial community under study gives great hopes for further fundamental studies of the metabolism of phosphate-accumulating organisms, and for improving biotechnologies for purifying wastewater from phosphorus.
The program relevance of future engineer creativity development on the basis of scientific research
Authors: Ryndak Valentina G. , Saifutdinova Gulmira S.
Published: July 2021

This paper contains answers to questions that show that the formation of creativity is vital for the future of the engineer, engineering education. At the same time, the authors explore how the creativity of future engineers should be formed in the process of studying at a technical university, and propose strategies to make creativity a part of every engineering curriculum and course. The paper presents the relevance of the program for the formation of the future engineers creativity based on the theoretical analysis of the world experience of domestic and foreign scientists. The possibilities and methods of its implementation in the process of scientific research are shown. The presented research is based on the theory of knowledge, the activity approach, the pedagogy of creativity and the methodology of scientific research. The best practices of foreign scientists in solving the problem of forming the creativity of future engineers are presented. The purpose of the study is to justify the need to create a program aimed at developing the creativity of future engineers.
Um diálogo entre biopolítica e colonialidade a partir da intervenção militar no Rio de Janeiro
Authors: Santana Ygor Santos de , De Ávila Flávia
Published: July 2021

Resumo: A intervenção federal no Estado do Rio de Janeiro caracterizou-se pela forte presença das Forças Armadas nas favelas, aumento de homicídios e outras violências contra seus moradores. Este trabalho objetiva discutir essa intervenção enquanto inflexão de uma lógica mais ampla de guerra contra as pessoas não-brancas, fundante do Estado Brasileiro, desde os genocídios coloniais. Divide-se em quatro seções. A primeira analisa relatos de moradores da favela, produzidos no Circuito Favelas por Direitos, que mostram concretamente a relação entre exceção e colonialidade. A segunda apresenta a disciplina jurídica da intervenção. A terceira aborda a relação de exceção formadora dos Estados modernos, os quais definem diferencialmente os limites político-jurídicos da vida humana. A quarta apresenta como a exceção, nos países formados pelas invasões coloniais, entrelaça-se a discursos racistas numa matriz colonial de poder, produtora da desumanização e do genocídio de setores inteiros da população. Metodologicamente, baseia-se na análise documental e na revisão bibliográfica. Conclui-se que a ação estatal brasileira é constitutivamente orientada por uma matriz colonial de poder, que define quais vidas serão protegidas e quais serão expostas à morte generalizada.Palavras-chave: biopolítica, colonialidade, pensamento decolonial, militarização, racismo, estado de exceção, intervenção.Abstract: The federal intervention in the State of Rio de Janeiro was characterized by a strong presence of the Armed Forces in the favelas, more homicides and other violence against residents. This paper discusses the intervention as inflection of a broader war logic against non-white people, that founds the Brazilian State, since the colonial genocides. It's divided into four sections. The first analyzes reports from favela residents, gathered in the Circuito Favela por Direitos, which concretely show the relationship between exception and coloniality. The second presents the legal discipline of the intervention. The third addresses exception, forming relation of modern States, which differentially define human life's political-legal limits . The fourth presents how the exception, in countries formed by colonial invasions, is intertwined with racist discourses in a colonial matrix of power, which produces dehumanization and genocide for entire population sectors. Methodologically, it is based on documentary analysis and bibliographic review. The conclusion is that a colonial matrix of power constitutively guides the Brazilian state action, which defines the lives that'll be protected and those that'll be exposed to generalized death. Keywords: biopolitics, coloniality, decolonial thinking, militarization, racism, state of exception, intervention.
First clinical experience of a new surgical technique including correction of bony alignment of first foot ray combined with reconstruction of muscle balance in case of adolescent hallux valgus
Authors: Fishkin Michael V. , Fomenko Maxim V. , Schermann Haggai
Published: July 2021

BACKGROUND: Hallux valgus deformity of the big toe in adolescents accounts for 22%44% of all relevant cases. Despite a relatively large number of surgical treatment methods proposed to correct this deformity, treatment results are not always satisfactory. The problem of imbalance between the external traction of the abductor hallucis muscle and the contracted adductor muscle in hallux valgus remains controversial and is not covered in the literature.
AIM: This study aimed to examine the results of hallux valgus deformity treatment, following the suggested combined technique.
MATERIALS AND METHODS: Eight teenage patients (10 feet), aged 15 years on average, were assessed. Patients were undergoing treatment in the department of pediatric orthopedics of the Dana Hospital, Tel Aviv, within the period from 2015 to 2019. The average postoperative observation period was 30 months. This study suggested a new combined technique, including (1) modified oblique Chevron osteotomy with a V-shaped cut in the distal aspect of the first metatarsal with the dorsal wedge excision performed at the apex of its angulation, (2) valgus osteotomy of the medial cuneiform bone with the insertion of the V-shaped bone allograft, and (3) transfer of the dorsal portion of the pre-split tendon of abductor hallucis muscle to the base of the triangular medial capsular flap of the first metatarsophalangeal joint (MPJ). The tendon received optimal tension to restore the muscular balance.
RESULTS: This surgical technique provided safe and stable correction of the hallux valgus deformity, restored muscular balance, avoided movement restriction of the first MPJ, and restored the function and strength of the abductor halluces muscle that prevented the recurrence of the deformity. The number of good and excellent results was much greater than those in published reports.
CONCLUSIONS: Despite a relatively small group of patients, the suggested technique has shown improvements in hallux valgus deformity in adolescents.
Attenuation of coda waves in the Dead Sea region
Authors: Eck Torild van
Published: July 2021

Coda waves of local small earthquakes in the Dead Sea region, part of the Jordan rift structure, show frequency invariant codas, that is Qc = Q0(f/f0)n, with Q0 = 65 ± 5, f0 = 1 Hz and n = 1.05 ± 0.04 for hypocentral distances between 10 and 55 km, and lapse times less than 60 sec. This justifies, for example, the use of part of the coda for relative site response studies. Lacking direct Qβ measurements, Qc might be considered as a first approximation of Qβ for the region. For short hypocentral distances, r < 20 km, rapidly increasing Qc with lapse time, t, has been observed.
Lg magnitudes and yield estimates for underground Novaya Zemlya nuclear explosions
Authors: Nuttli Otto W.
Published: July 2021

Lg-wave amplitudes of 30 Novaya Zemlya underground nuclear explosions, as recorded by short-period seismographs in Denmark, Finland, Germany, Norway, Spitsbergen, and Sweden, are used to determine mb(Lg) values. Assuming that the mb(Lg) versus explosion yield relation derived from Nevada Test Site data applies to all continental areas, the yields of the explosions are estimated. They cover a large range of values, from 2.5 to 4900 kt. The largest explosion since April 1976 had an estimated yield of 145 kt.

The mb(Lg) values, when subtracted from the mb(P) values, can be used to estimate the mb(P) bias between two test sites. In this way, the mb(P) bias between Novaya Zemlya and the Nevada Test Site is estimated to be 0.20 magnitude units.
Triggered slip along the San Andreas fault after the 8 July 1986 North Palm Springs earthquake
Authors: Williams Patrick L. , McGill Sally Fagerson , Sieh Kerry E. , Allen Clarence R. , Louie John N.
Published: July 2021

In addition to minor surface cracks in the region of the 8 July 1986 North Palm Springs earthquake, minor aseismic surficial rupture occurred along three segments of the San Andreas fault, 44 to 86 km southeast of the epicenter. Data from a creepmeter and a tiltmeter at one locality suggest that triggered slip occurred coseismically beneath the instruments but took 33 hr to propagate to the surface. That slippage occurred coseismically at depth favors mechanisms for triggered slip that involve dynamic or static strain changes rather than creep migrating from the source region.

The distribution of slip along the San Andreas fault associated with the North Palm Springs earthquake differed significantly from that recorded after the moderate 1968 Borrego Mountain, California and 1979 Imperial Valley, California, earthquakes. During these earthquakes, triggered slip occurred along the San Andreas fault in the Durmid Hill area and in the Mecca Hills. Triggered slip associated with the North Palm Springs earthquake occurred in these two areas again, but also extended farther northwest into the Indio Hills, where as much as 9 mm of dextral slip occurred. In the Mecca Hills, surface cracks in 1986 appeared over a shorter fault length than in previous events, and the dextral displacement was smaller, with maximum values of only 2 to 3 mm. On Durmid Hill, surface cracks in 1986 were localized along a 200-m-long stretch of the fault spanning the Mecca Beach creepmeter and extending about 150 m to the southeast. Right-lateral displacements on surface cracks in this area were 1.4 to 2.0 mm, smaller than those observed in previous events.

Although the mechanism of triggered aseismic slip is poorly understood, examination of displacement rates for the past several decades to centuries may indicate whether the aseismic slip rate is constant or represents accelerating premonitory failiure of the southernmost San Andreas fault.
Modeling teleseismicSVwaves from underground explosions with tectonic release: Results for Southern Novaya Zemlya
Authors: Cohee Brian P. , Lay Thorne
Published: July 2021

Detailed forward modeling of long-period shear waves for two large underground explosions at the Southern Novaya Zemlya test site indicates that the appropriate equivalent double-couple orientation for the tectonic release radiation is vertical strike-slip. Previous studies of observed teleseismic SH waveforms and SV amplitudes for the 27 October 1973 and 2 November 1974 events using geometric ray theory could not distinguish between vertical strike-slip and 45°-dipping thrust geometries. Either mechanism can match the observed four-lobed SH radiation pattern, and the two-lobed SV amplitude pattern can be produced by interference with an appropriate size explosion pS signal. However, the complexity of the observed SV waveforms arising from Sp conversions near the receiver, diffracted Sp, and shear-coupled PL phases is not accounted for in the ray theory synthetics. Incorporating more realistic Green's functions using Baag and Langston's (1985b) WKBJ spectral method allows more complete modeling of the SV signals. Due to differences in frequency content between the explosion and double-couple SV waveforms, constructive interference occurs more efficiently than destructive interference when the two signals are linearly superimposed. As a result, using tectonic release moments determined from the SH waves and the optimum F factors required to match the SV amplitude patterns, the waveforms produced by the strike-slip and thrust orientations differ substantially at some azimuths. The strike-slip solution yields a consistently superior match to the data. Using the EU2 model of Lerner-Lam and Jordan (1987) for the source region and either EU2 or TNA (Grand and Helmberger, 1984) for the receiver structure, together with an attenuation model similar to SL8, we obtain a double-couple moment, M0 = 3.2 × 1024 dyne-cm and explosion source strength, ψ∞ = 3.8 ± 0.5 × 1011 cm3 for the 27 October 1973 event, and M0 = 1.7 × 1024 dyne-cm and ψ∞ = 2.0 ± 0.3 × 1011 cm3 for the 2 November 1974 event. Complete waveform modeling of SV signals can thus provide improved constraints on tectonic release radiation and explosion source strength.
Quasi-continental oceanic structure beneath the Arabian Fan sediments from observed surface-wave dispersion studies
Authors: Singh D. D.
Published: July 2021

The fundamental and higher modes of surface waves generated by 31 earthquakes and recorded at seismographic stations along the western margins of India and Pakistan (Trivandrum, Kodaikanal, Goa, Bombay, Poona, New Delhi, Nillore, and Quetta) are used to estimate the crustal structure beneath the Arabian Fan sediments. The sedimentary thickness is determined from the observed higher mode data. The observed dispersion data suggest an increase in crustal thickness northward, from an approximately 16 km crustal thickness at the southern tip of India (Trivandrum) to an approximately 28 km crustal thickness at the regions of 20°N and above latitude, with an overlying 6 km sedimentary thickness. This gradual increase in crustal thickness in the northward direction and the attaining of quasi-continental oceanic (transition from continent to ocean) structure beneath the Arabian Fan sediments suggest that the Mohorovičić discontinuity may have resulted from a change in crystal structure due to increase of pressure and not a phase change. The same material exists beneath the Moho, and it does not represent the boundary between two different materials. The transition has given rise to crustal thickening in the northward direction. Another possible explanation is that the increase in hydrostatic pressure due to the load exerted by a large sedimentary column together with horizontal pressure caused by the collision of Indian and Eurasian plates has given rise to an increase in temperature near the Moho. Because of the thermal blanketing effect of this large sedimentary column, an inferred rise in temperature may have either changed the upper mantle into material with crustal-like velocity or may have given rise to metamorphism of earlier existing sedimentary rocks. An inferred high temperature near the Moho depth beneath the Arabian Fan sediments is in close agreement with the high attenuating zone at the shallow depth (30 to 45 km) as determined by Singh (1987).
Elastic-wave propagation and site amplification in the Salt Lake valley, Utah, from simulated normal faulting earthquakes
Authors: Benz Harley M. , Smith Robert B.
Published: July 2021

The two-dimensional seismic response of the Salt Lake valley to near- and far-field earthquakes has been investigated from simulations of vertically incident plane waves and from normal-faulting earthquakes generated on the basin-bounding Wasatch fault. The response to normal faulting earthquakes was simulated using a two-dimensional finite-element method and the plane-wave response was calculated from two-dimensional finite-difference simulations. The plane-wave simulations were then compared with observed site amplifications in the Salt Lake valley, based on seismic recordings from nuclear explosions in southern Nevada, that show 10 times greater amplification within the basin than measured values on hard-rock sites. While previous studies attribute this increased site amplification to the near-surface unconsolidated/consolidated alluvial fill contact, our synthetic seismograms suggest that in the frequency band 0.3 to 1.5 Hz at least one-half the site amplification can be attributed to the impedance contrast between the basin sediments and higher velocity basement rocks. Synthetic seismograms from vertically incident plane-wave sources and buried double-couple sources predict large amplitude Rayleigh-wave propagation from the edges of the basin and, in general, uniform site amplification. In contrast, near-field simulations of basin-bounding, normal-faulting earthquakes predict large-amplitude Rayleigh waves propagating westward from the fault across the basin. Spectra of synthetic accelerograms computed from the normal-faulting earthquakes shows that spectral amplification within the basin is primarily due to source directivity with a maxima near the surface projection of the fault that decays rapidly away from the fault. Importantly, the synthetic modeling of near-field earthquake sources show that near-field directivity effects are important and should be considered in an earthquake hazard assessment of the Salt Lake valley and similar geologic settings along the Wasatch Front.
Pulse propagation in random media by a causal approach
Authors: Beltzer Abraham I. , Wegner Joanne , Tittman Bernard R. , Haddow James B.
Published: July 2021

A causal approach is applied to investigate pulse propagation in random media, which exhibit scattering and viscoelastic losses. Since the approach allows for evaluation of the effective wave number for the entire frequency interval, the transients may be investigated by the classical Fourier method. The scattering mechanism is described by a model introduced by Wu, and the viscoelastic losses by a slightly modified Azimi's law. Extensive numerical results for a transient response of this Wu-Azimi model are presented. It is shown how the pulse reinforcing and delaying effects of multiple scattering are interrelated through a causality constraint.
Network calibration forLgmagnitude—method and test results from eastern Canada
Authors: Chun Kin-Yip , Kokoski Richard J. , West Gordon F.
Published: July 2021

We present a method of calibrating a regional network of seismographic stations for Lg-wave site responses. Characterized by remarkable simplicity and practicality, the calibration procedure involves merely the determination of what we call calibration curves, defined as the frequency-dependent station site responses relative to that of a reference station. The method is used to calibrate a group of twelve stations belonging to the Eastern Canada Telemetered Network (ECTN), with an SRO-type station (GAC) serving as a reference station. The calibration curves are employed in a test application to Lg amplitude data from 50 small- to moderate-sized earthquakes (mLg (f) between 1.4 and 5.3). We found that use of the calibration curves leads to a systematic reduction in the variance of the station magnitude estimates of 37 per cent. A calibrated network minimizes station-specific systematic biases between the network magnitudes and those determined at any given station. As a result, it allows meaningful applications of empirically developed magnitude/yield relationship for stimulation of underground nuclear explosion yields, even when they are well recorded at very few stations of an in-country monitoring network.
A comparative study of island, seafloor, and subseafloor ambient noise levels
Authors: Hedlin Michael A. H. , Orcutt John A.
Published: July 2021

A study of seafloor and island stations shows that for the frequency band 0.1 to 10 Hz the seismic noise levels on islands are comparable to the levels on the seafloor. The microseism peak at the seafloor appears to be comparable to the highest levels observed on small islands. For this band, seafloor stations are realistic alternatives when island sites are not available.

Seven year averages of the ambient noise levels recorded by Seismic Research Observatory (SRO) stations on three islands (Guam [GUMO], Taiwan [TATO], and New Zealand's north island [SNZO]) are compared with those recorded by the International Deployment of Accelerometers (IDA) station on Easter Island and on and beneath the ocean floor by Ocean Bottom Seismometers (OBSs) and the Marine Seismic System (MSS) deployed in a south Pacific DSDP drill hole at 23.8°S., 165.5°W (Adair et al., 1986). From 0.3 to 2 Hz the SRO displacement power levels fall in the range historically observed by the Scripps' OBSs (decreasing at 70 dB/decade from 1 by 106 nm2/Hz at 0.3 Hz to 1 nm2/Hz at 2 Hz) and are 10 to 15 dB above MSS levels. Above 2 Hz it appears that the same ratios hold (the SRO power levels decrease at 70 dB/decade to 1 by 10−3 nm2/Hz at a frequency of 10 Hz), although this correlation is based on very limited, high gain, short-period data. At frequencies below 0.3 Hz the SRO noise levels peak and decrease to approximately 2 by 103 nm2/Hz at 40 mHz. The noise levels recorded at Easter Island are somewhat higher (decreasing at 70 dB/decade from 1 by 107 nm2/Hz at 0.2 Hz to 1 nm2/Hz at 10 Hz and to 1 by 105 nm2/Hz at 50 mHz). At the microseism peak near 0.2 Hz the MSS levels are from 15 to 20 dB higher than observed by the SRO stations and equivalent to those recorded at Easter Island. There appears to be little dependence of the variance in noise level estimates on frequency. The upper 95 per cent confidence limit generally lies 10 dB above the average noise levels for all island stations.

All island noise level curves are dominated by the broad double-frequency microseism peak centered between 0.15 to 0.2 Hz. The single-frequency peak ranges from absent (Easter Island) to discernable (Guam and New Zealand) to obvious (at Taiwan). The center frequency of this peak ranges from 0.07 Hz at Guam and New Zealand to 0.1 Hz at Taiwan. We speculate that the increased amplitude and frequency of the single-frequency microseism peak is due to the interaction between the shallow continental shelf and surface gravity waves and/or the presence of Taiwan in a region of limited fetch.
Pre-earthquake displacement and triggered displacement on the Imperial fault associated with the Superstition Hills earthquake of 24 November 1987
Authors: Sharp Robert V.
Published: July 2021

Two right-lateral slip events, about 3 weeks apart in November 1987, broke the surface discontinuously along probably similar, nearly 20 km lengths of the northern Imperial fault. The first displacement, at about the beginning of November, was accompanied by a surface tilt representing deep vertical motion or distributed strain. This movement may have been part of a more regional event that also involved the southern San Andreas fault, although the evidence there is questionable. The later surface offset was triggered, probably by the second main shock of the 24 November earthquakes located in the Superstition Hills, about 37 km northwest of the Imperial fault. The maximum observed displacement was less than 4 cm on both occasions; for the triggered movement the maximum slip occurred on a branch strand near the northern extremity of the fault.

Pre-earthquake resurveys of short-length leveling lines indicated combined surface displacement and an eastward tilt at two locations between surveys 712 months apart and 13 months apart; the tilt at Harris Road during this pre-earthquake interval is modeled as a 1.4 cm vertical component of slip deeper than 100 m on a 70° northeastward-dipping fault. Later resurveys showed a marked reduction of deep movement in the time period including the triggered slip, and between December 1987 and January 1988, it had ceased.

No definite evidence of surface fracturing was found in the Brawley fault zone during either period of time when the Imperial fault moved. Remeasurement of leveling lines there indicated small, very near-surface vertical components of movement in the northern half of the zone. Elevation changes in the southern part indicated distributed strain and/or movement only deeper than about 50 m. The Brawley zone changes are not fixed in time well enough to clearly relate them to the surface movements on the Imperial fault.
Waveform modeling of the November 1987 Superstition Hills earthquakes
Authors: Bent Allison L. , Helmberger Donald V. , Stead Richard J. , Ho-Liu Phyllis
Published: July 2021

Long-period body-wave data recorded at teleseismic distances and strong-motion data at Pasadena for the Superstition Hills earthquakes of 24 November 1987 are modeled to obtain the source parameters. We will refer to the event that occurred at 0153 UT as EQ1 and the event at 1316 UT as EQ2. At all distances the first earthquake appears to be a simple left-lateral strike-slip event on a fault striking NE. It is a relatively deep event with a source depth of 10 km. It has a teleseismic moment of 2.7 ×1025 dyne cm. The second and more complex event was modeled in two ways: by using EQ1 as the Green's function and by using a more traditional forward modeling technique to create synthetic seismograms. The first method indicated that EQ2 was a double event with both subevents similar, but not identical to EQ1 and separated by about 7.5 sec. From the synthetic seismogram study we obtained a strike of 305° for the first subevent and 320° for the second. Both have dips of 80° and rakes of 175°. The first subevent has a moment of 3.6 ×1025 which is half that of the second. We obtain depths of at least 6 km. The teleseismic data indicate a preferred subevent separation of 30 km with the second almost due south of the first, but the error bounds are substantial. This would suggest that the subevents occurred on conjugate faults. The strong-motion data at PAS, however, imply a much smaller source separation, with the sources probably produced by asperities.