46 research outputs found

    A global apparent polar wander path for the last 320 Ma calculated from site-level paleomagnetic data

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    Apparent polar wander paths (APWPs) calculated from paleomagnetic data describe the motion of tectonic plates relative to the Earth's rotation axis through geological time, providing a quantitative paleogeographic framework for studying the evolution of Earth's interior, surface, and atmosphere. Previous APWPs were typically calculated from collections of paleomagnetic poles, with each pole computed from collections of paleomagnetic sites, and each site representing a spot reading of the paleomagnetic field. It was recently shown that the choice of how sites are distributed over poles strongly determines the confidence region around APWPs and possibly the APWP itself, and that the number of paleomagnetic data used to compute a single paleomagnetic pole varies widely and is essentially arbitrary. Here, we use a recently proposed method to overcome this problem and provide a new global APWP for the last 320 million years that is calculated from simulated site-level paleomagnetic data instead of from paleopoles, in which spatial and temporal uncertainties of the original datasets are incorporated. We provide an updated global paleomagnetic database scrutinized against quantitative, stringent quality criteria, and use an updated global plate motion model. The new global APWP follows the same trend as the most recent pole-based APWP but has smaller uncertainties. This demonstrates that the first-order geometry of the global APWP is robust and reproducible. Moreover, we find that previously identified peaks in APW rate disappear when calculating the APWP from site-level data and correcting for a temporal bias in the underlying data. Finally, we show that a higher-resolution global APWP frame may be determined for time intervals with high data density, but that this is not yet feasible for the entire 320–0 Ma time span. Calculating polar wander from site-level data provides opportunities to significantly improve the quality and resolution of the global APWP by collecting large and well-dated paleomagnetic datasets from stable plate interiors, which may contribute to solving detailed Earth scientific problems that rely on a paleomagnetic reference frame

    La construcciĂłn polĂ­tica de la desigualdad : Pobreza y Sexualidad en las polĂ­ticas pĂșblicas de la Provincia de CĂłrdoba

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    El proyecto pretende analizar la definiciĂłn de polĂ­ticas pĂșblicas sobre pobreza y ambiente como instancias de visibilizaciĂłn de posiciones y discursividades en conflicto sobre la (des)igualdad. Asimismo pretende entender la formulaciĂłn de polĂ­ticas pĂșblicas como instancias en que los Estados institucionalizan una definiciĂłn sobre la (des)igualdad que muchas veces, paradĂłjicamente, resulta en la instauraciĂłn de exclusiones y el fortalecimiento de regĂ­menes de dominaciĂłn. Entre las diversas hipĂłtesis que guĂ­an el proyecto la mĂĄs abarcativa sostiene que las decisiones, los modos y campos de intervenciĂłn definidos en la polĂ­tica pĂșblica constituyen en sĂ­ mismos un espacio discursivo en el que se establecen definiciones y plasman matrices ideolĂłgicas respecto de la (des)igualdad. Pues a partir de ellos se visibilizan operaciones especĂ­ficas de inclusiĂłn/exclusiĂłn, igualdad/desigualdad, prohibiciĂłn/habilitaciĂłn, etc.; se identifican y caracterizan sujetos; asĂ­ como tambiĂ©n un determinado orden normativo de relaciones y prĂĄcticas. No obstante encontrarse legalmente instituida la igualdad como principio subyacente a todo el ordenamiento de derechos, en la prĂĄctica las desigualdades se hacen patentes. Éstas son especialmente relevantes en tres ĂĄreas de polĂ­ticas pĂșblicas: el trabajo, el hĂĄbitat y sexualidad. Consecuentemente, se propone: 1. analizar el dispositivo de regulaciĂłn tal como se materializa en las decisiones, leyes y polĂ­ticas pĂșblicas del Estado Provincial; 2. Esclarecer las disputas y/o articulaciones de orientaciones y prĂĄcticas de distintos ĂĄmbitos institucionales –expresamente referimos al conjunto de actores que se activan y pujan frente al contenido y carĂĄcter de las decisiones pĂșblicas; 3. estudiar las prĂĄcticas de resistencia frente a las regulaciones instituidas.Fil: Ciuffolini, MarĂ­a Alejandra. Universidad CatĂłlica de CĂłrdoba. Facultad de Ciencia PolĂ­tica y Relaciones Internacionales; ArgentinaFil: Avalle, Gerardo. Universidad CatĂłlica de CĂłrdoba. Facultad de Ciencia PolĂ­tica y Relaciones Internacionales; ArgentinaFil: Ibaña, Griselda Beatriz. Universidad CatĂłlica de CĂłrdoba. Facultad de Ciencia PolĂ­tica y Relaciones Internacionales; Argentin

    Territorios en disputa. Un estudio sobre los conflictos territoriales urbanos y rurales en la provincia de CĂłrdoba.

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    El territorio es el resultado de un conjunto de dispositivos -polĂ­ticos, econĂłmicos, culturales- y de disposiciones sociales que, en su concurrencia y/o contradicciĂłn, configuran tanto identidades y campos de comportamiento posibles, como un particular modo de producir y relacionarse con la naturaleza. Entendido asĂ­, el territorio y sus posibilidades son el resultado de relaciones de fuerza desplegadas en torno al control y posesiĂłn de recursos sociales, econĂłmicos, naturales, etc. Estas fuerzas condensan en una especĂ­fica -es decir histĂłrica- particiĂłn del territorio y en formas tambiĂ©n especĂ­ficas de distribuciĂłn y jerarquizaciĂłn de los elementos y sujetos dispuestos en Ă©l. Esto implica pensar el territorio no solamente como dominio del Estado que lo administra, ordena y controla, sino tambiĂ©n como resultante de los imperativos del capital, y como espacio de conflictos y resistencias. Se trata de una mirada que, sin descuidar esas dos dimensiones -accionar estatal y accionar del capital- privilegia enfocar el anĂĄlisis del territorio a partir de conflictos que en Ă©l se desatan, entre los modos y prĂĄcticas de intervenciĂłn del Estado, las intervenciones del capital y las resistencias y luchas que la poblaciĂłn residente entabla frente o a partir de ellos. En este marco, el interĂ©s de este proyecto es analizar los distintos conflictos en torno a la tierra, sus usos y disposiciĂłn en la provincia de CĂłrdoba, a fin de conocer: la configuraciĂłn de los conflictos; la confluencia de polĂ­ticas; los proyectos, intereses, y obstĂĄculos de desarrollo territorial. Su concreciĂłn nos permitirĂĄ acceder a una Ășltima instancia de observaciĂłn y elaboraciĂłn propuestas de gestiĂłn e intervenciĂłn sobre los territorios que tengan en cuenta la participaciĂłn y los intereses de las comunidades involucradas. La hipĂłtesis de trabajo que orienta nuestra propuesta de estudio sostiene que los modos de intervenciĂłn del Estado y el capital tienen fuerte contenido performativo de los espacios sociales, en tanto la conflictividad desatada en los territorios no es otra cosa que la conformaciĂłn de subjetividades colectivas que denuncian un modo especĂ­fico de configuraciĂłn del espacio en tensiĂłn con las racionalidades socio-locales

    Territorios en disputa. Un estudio sobre los conflictos territoriales urbanos y rurales en la provincia de CĂłrdoba

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    El territorio es el resultado de un conjunto de dispositivos -polĂ­ticos, econĂłmicos, culturales- y de disposiciones sociales que, en su concurrencia y/o contradicciĂłn, configuran tanto identidades y campos de comportamiento posibles, como un particular modo de producir y relacionarse con la naturaleza. Entendido asĂ­, el territorio y sus posibilidades son el resultado de relaciones de fuerza desplegadas en torno al control y posesiĂłn de recursos sociales, econĂłmicos, naturales, etc. Estas fuerzas condensan en una especĂ­fica -es decir histĂłrica- particiĂłn del territorio y en formas tambiĂ©n especĂ­ficas de distribuciĂłn y jerarquizaciĂłn de los elementos y sujetos dispuestos en Ă©l. Esto implica pensar el territorio no solamente como dominio del Estado que lo administra, ordena y controla, sino tambiĂ©n como resultante de los imperativos del capital, y como espacio de conflictos y resistencias. Se trata de una mirada que, sin descuidar esas dos dimensiones -accionar estatal y accionar del capital- privilegia enfocar el anĂĄlisis del territorio a partir de conflictos que en Ă©l se desatan, entre los modos y prĂĄcticas de intervenciĂłn del Estado, las intervenciones del capital y las resistencias y luchas que la poblaciĂłn residente entabla frente o a partir de ellos. En este marco, el interĂ©s de este proyecto es analizar los distintos conflictos en torno a la tierra, sus usos y disposiciĂłn en la provincia de CĂłrdoba, a fin de conocer: la configuraciĂłn de los conflictos; la confluencia de polĂ­ticas; los proyectos, intereses, y obstĂĄculos de desarrollo territorial. Su concreciĂłn nos permitirĂĄ acceder a una Ășltima instancia de observaciĂłn y elaboraciĂłn propuestas de gestiĂłn e intervenciĂłn sobre los territorios que tengan en cuenta la participaciĂłn y los intereses de las comunidades involucradas. La hipĂłtesis de trabajo que orienta nuestra propuesta de estudio sostiene que los modos de intervenciĂłn del Estado y el capital tienen fuerte contenido performativo de los espacios sociales, en tanto la conflictividad desatada en los territorios no es otra cosa que la conformaciĂłn de subjetividades colectivas que denuncian un modo especĂ­fico de configuraciĂłn del espacio en tensiĂłn con las racionalidades socio-locales.Fil: Ciuffolini, MarĂ­a Alejandra. Universidad CatĂłlica de CĂłrdoba. Facultad de Ciencia PolĂ­tica y Relaciones Internacionales; ArgentinaFil: Avalle, Gerardo. Universidad CatĂłlica de CĂłrdoba. Facultad de Ciencia PolĂ­tica y Relaciones Internacionales; Argentin

    O efeito de borda influencia a estrutura da comunidade vegetal em uma floresta tropical seca?

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    Efeitos de borda sĂŁo considerados fator-chave na regulação da estrutura de comunidades vegetais em diferentes ecossistemas. Entretanto, apesar dos poucos estudos relacionados, o efeito de borda parece nĂŁo ser determinante em regiĂ”es semiĂĄridas, como a floresta tropical seca brasileira, conhecida como Caatinga. Este estudo testou a hipĂłtese nula de que a comunidade vegetal arbustivo-arbĂłrea nĂŁo sofre alteraçÔes em sua estrutura, riqueza e composição devido ao efeito de borda. Foram instaladas 24 parcelas (20 x 20 m) em um fragmento de Caatinga arbĂłrea, sendo 12 parcelas na borda do fragmento e 12 parcelas no seu interior. A riqueza, abundĂąncia e composição das espĂ©cies nĂŁo diferiram estatisticamente entre as parcelas de borda e interior. Os resultados deste estudo corroboram um possĂ­vel padrĂŁo de ambientes semiĂĄridos e contrastam com resultados anteriores de diferentes ambientes, como florestas tropicais Ășmidas, cerrado e floresta de araucĂĄria. Indicam diferenças abruptas entre comunidades vegetais da borda e do interior de fragmentos florestais, sugerindo que a comunidade arbustivo-arbĂłrea da Caatinga nĂŁo Ă© ecologicamente afetada pela presença de bordas._________________________________________________________________________________________ ABSTRACT: Edge effects are considered a key factor in regulating the structure of plant communities in different ecosystems. However, regardless to few studies, edge influence does not seem to be decisive in semiarid regions such as the Brazilian tropical dry forest known as Caatinga but this issue remains inconclusive. The present study tests the null hypothesis that the plant community of shrubs and trees does not change in its structure due to edge effects. Twenty-four plots (20 x 20 m) were set up in a fragment of Caatinga, in which 12 plots were in the forest edges and 12 plots were inside the fragment. Tree richness, abundance and species composition did not differ between edge and interior plots. The results of this study are in agreement with the pattern previously found for semiarid environments and contrasts with previous results obtained in different environments such as Rainforests, Savanna and Forest of Araucaria, which indicate abrupt differences between the border and interior of the plant communities in these ecosystems, and suggest that the community of woody plants of the Caatinga is not ecologically affected by the presence of edges

    Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

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    Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

    Global disparities in surgeons’ workloads, academic engagement and rest periods: the on-calL shIft fOr geNEral SurgeonS (LIONESS) study

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    : The workload of general surgeons is multifaceted, encompassing not only surgical procedures but also a myriad of other responsibilities. From April to May 2023, we conducted a CHERRIES-compliant internet-based survey analyzing clinical practice, academic engagement, and post-on-call rest. The questionnaire featured six sections with 35 questions. Statistical analysis used Chi-square tests, ANOVA, and logistic regression (SPSSŸ v. 28). The survey received a total of 1.046 responses (65.4%). Over 78.0% of responders came from Europe, 65.1% came from a general surgery unit; 92.8% of European and 87.5% of North American respondents were involved in research, compared to 71.7% in Africa. Europe led in publishing research studies (6.6 ± 8.6 yearly). Teaching involvement was high in North America (100%) and Africa (91.7%). Surgeons reported an average of 6.7 ± 4.9 on-call shifts per month, with European and North American surgeons experiencing 6.5 ± 4.9 and 7.8 ± 4.1 on-calls monthly, respectively. African surgeons had the highest on-call frequency (8.7 ± 6.1). Post-on-call, only 35.1% of respondents received a day off. Europeans were most likely (40%) to have a day off, while African surgeons were least likely (6.7%). On the adjusted multivariable analysis HDI (Human Development Index) (aOR 1.993) hospital capacity > 400 beds (aOR 2.423), working in a specialty surgery unit (aOR 2.087), and making the on-call in-house (aOR 5.446), significantly predicted the likelihood of having a day off after an on-call shift. Our study revealed critical insights into the disparities in workload, access to research, and professional opportunities for surgeons across different continents, underscored by the HDI

    Economic consequences of investing in anti-HCV antiviral treatment from the Italian NHS perspective : a real-world-based analysis of PITER data

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    OBJECTIVE: We estimated the cost consequence of Italian National Health System (NHS) investment in direct-acting antiviral (DAA) therapy according to hepatitis C virus (HCV) treatment access policies in Italy. METHODS: A multistate, 20-year time horizon Markov model of HCV liver disease progression was developed. Fibrosis stage, age and genotype distributions were derived from the Italian Platform for the Study of Viral Hepatitis Therapies (PITER) cohort. The treatment efficacy, disease progression probabilities and direct costs in each health state were obtained from the literature. The break-even point in time (BPT) was defined as the period of time required for the cumulative costs saved to recover the Italian NHS investment in DAA treatment. Three different PITER enrolment periods, which covered the full DAA access evolution in Italy, were considered. RESULTS: The disease stages of 2657 patients who consecutively underwent DAA therapy from January 2015 to December 2017 at 30 PITER clinical centres were standardized for 1000 patients. The investment in DAAs was considered to equal €25 million, €15 million, and €9 million in 2015, 2016, and 2017, respectively. For patients treated in 2015, the BPT was not achieved, because of the disease severity of the treated patients and high DAA prices. For 2016 and 2017, the estimated BPTs were 6.6 and 6.2 years, respectively. The total cost savings after 20 years were €50.13 and €55.50 million for 1000 patients treated in 2016 and 2017, respectively. CONCLUSIONS: This study may be a useful tool for public decision makers to understand how HCV clinical and epidemiological profiles influence the economic burden of HCV
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