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The formation and preservation of cratons-the oldest parts of the continents, comprising over 60 per cent of the continental landmass-remains an enduring problem. Key to craton development is how and when the thick strong mantle roots that underlie these regions formed and evolved. Peridotite melting residues forming cratonic lithospheric roots mostly originated via relatively low-pressure melting and were subsequently transported to greater depth by thickening produced by lateral accretion and compression. The longest-lived cratons were assembled during Mesoarchean and Palaeoproterozoic times, creating the stable mantle roots 150 to 250 kilometres thick that are critical to preserving Earth's early continents and central to defining the cratons, although we extend the definition of cratons to include extensive regions of long-stable Mesoproterozoic crust also underpinned by thick lithospheric roots. The production of widespread thick and strong lithosphere via the process of orogenic thickening, possibly in several cycles, was fundamental to the eventual emergence of extensive continental landmasses-the cratons.
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A model for intermediate-depth earthquakes of subduction zones is evaluated based on shear localization, shear heating, and runaway creep within thin carbonate layers in an altered downgoing oceanic plate and the overlying mantle wedge. Thermal shear instabilities in carbonate lenses add to potential mechanisms for intermediate-depth seismicity, which are based on serpentine dehydration and embrittlement of altered slabs or viscous shear instabilities in narrow fine-grained olivine shear zones. Peridotites in subducting plates and the overlying mantle wedge may be altered by reactions with CO2-bearing fluids sourced from seawater or the deep mantle, to form carbonate minerals, in addition to hydrous silicates. Effective viscosities of magnesian carbonates are higher than those for antigorite serpentine and they are markedly lower than those for H2O-saturated olivine. However, magnesian carbonates may extend to greater mantle depths than hydrous silicates at temperatures and pressures of subduction zones. Strain rates within altered downgoing mantle peridotites may be localized within carbonated layers following slab dehydration. A simple model of shear heating and temperature-sensitive creep of carbonate horizons, based on experimentally determined creep laws, predicts conditions of stable and unstable shear with strain rates up to 10/s, comparable to seismic velocities of frictional fault surfaces. Applied to intermediate-depth earthquakes of the Tonga subduction zone and the double Wadati-Benioff zone of NE Japan, this mechanism provides an alternative to the generation of earthquakes by dehydration embrittlement, beyond the stability of antigorite serpentine in subduction zones.
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Serpentinization and carbonation of mantle rocks (peridotite alteration) are fundamentally important processes for a spectrum of geoscience topics, including arc volcanism, earthquake processes, chemosynthetic biological communities, and carbon sequestration. Data from a hydrophone array deployed in the Multi-Borehole Observatory (MBO) of the Oman Drilling Project demonstrates that free gas generated by peridotite alteration and/or microbial activity migrates through the formation in discrete bursts of activity. We detected several, minutes-long, swarms of gas discharge into Hole BA1B of the MBO over the course of a 9 month observation interval. The episodic nature of the migration events indicates that free gas accumulates in the permeable flow network, is pressurized, and discharges rapidly into the borehole when a critical pressure, likely associated with a capillary barrier at a flow constriction, is reached. Our observations reveal a dynamic mode of fluid migration during serpentinization, and highlight the important role that free gas can play in modulating pore pressure, fluid flow, and alteration kinetics during peridotite weathering.
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Mantle peridotite in Wadi Fins in eastern Oman exhibits three concentric alteration zones with oxide and sulfide mineralogy recording gradients in fO2 and fS2 (fugacity) of more than 20 orders of magnitude over 15-20 cm. The black cores of samples (approx. 5 cm in diameter) exhibit incomplete, nearly isochemical serpentinization, with relict primary mantle minerals (olivine, orthopyroxene and clinopyroxene) along with sulfide assemblages (pentlandite/heazlewoodite/bornite) recording low fO2 and moderate fS2. In addition to the black cores, two alteration zones are evident from their colouration in outcrop and hand samples: green and red. These zones exhibit non-isochemical alteration characterized by intergrowths of stevensite/lizardite. All three reaction zones are cut by calcite ± serpentine veins, which are most abundant in the outer, red zones, sometimes are flanked by narrow red and/or green zones where they cut the black zones, and thus may be approximately coeval with all three alteration zones. The alteration zones record progressively higher fO2 recorded by Ni-rich sulfides and iron oxides/hydroxides. These alteration zones lost 20-30% of their initial magnesium content, together with mobilization of iron over short distances from inner green zones into outer red zones, where iron is reprecipitated in goethite intermixed with silicates due to higher fO2. Thermodynamic modelling at 60°C and 50 MPa (estimated alteration conditions) reproduces sulfide assemblages, fO2 changes and Mg and Fe mobility. This article is part of a discussion meeting issue 'Serpentinite in the Earth system'.
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Involving 207 breast cancer patients a retrospective study was performed to facilitate the acceptance of the central pedicled, modified Wise-pattern therapeutic mammoplasty technique as a standard volume-displacement level II oncoplastic breast-conserving surgery (OBCS). The overall local recurrence rate was 5.8% with an average follow-up of 43.9 months. The median time to the initiation of the adjuvant treatment was 4.9 weeks. Due to positive surgical margins, 13 (6.84%) completional surgeries were performed. In total, 45 complications (12.9%) were recorded. The median values of the esthetic outcomes represented improved cosmetic results. The modified Wise-pattern technique could be a standard, safe and repeatable level II volume-displacement OBCS.
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Neoplasias de la Mama/cirugía , Mastectomía Segmentaria/métodos , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Estudios RetrospectivosRESUMEN
Carbon fluxes in subduction zones can be better constrained by including new estimates of carbon concentration in subducting mantle peridotites, consideration of carbonate solubility in aqueous fluid along subduction geotherms, and diapirism of carbon-bearing metasediments. Whereas previous studies concluded that about half the subducting carbon is returned to the convecting mantle, we find that relatively little carbon may be recycled. If so, input from subduction zones into the overlying plate is larger than output from arc volcanoes plus diffuse venting, and substantial quantities of carbon are stored in the mantle lithosphere and crust. Also, if the subduction zone carbon cycle is nearly closed on time scales of 5-10 Ma, then the carbon content of the mantle lithosphere + crust + ocean + atmosphere must be increasing. Such an increase is consistent with inferences from noble gas data. Carbon in diamonds, which may have been recycled into the convecting mantle, is a small fraction of the global carbon inventory.
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INTRODUCTION: Immediate breast reconstruction provides oncological safety, requires longer operation time. It does not influence the initiation of adjuvant therapy and radiological control, and results in favourable cosmetic outcome. AIM: Assessing the Hungarian data of immediate postmastectomy breast reconstructions, and comparing them to international findings. METHOD: Between May, 2011 and September, 2014 121 therapeutic and prophylactic, postmastectomy immediate breast reconstructions were performed in 100 patients. The clinico-pathological findings were assessed retrospectively, and surgical, oncological and cosmetic outcomes were evaluated statistically. RESULTS: The mean age of patients was 42.6 years, the follow up time was 29.4 months, and the duration of operation was 132 minutes. Skin-sparing mastectomy was performed most commonly (64%) with submuscular tissue expander placement (70%). Early postoperative complication was identified in 18 patients, and loco-regional recurrence in 1 patient. Most patients (89%) were satisfied with the cosmetic outcome. The average initiation time of adjuvant therapy was 4.8 weeks. CONCLUSIONS: Immediate breast reconstruction is a safe and effective option in line with international findings. Orv. Hetil., 2016, 157(46), 1830-1838.
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Implantes de Mama , Neoplasias de la Mama/cirugía , Mamoplastia/métodos , Satisfacción del Paciente , Colgajos Quirúrgicos , Adulto , Neoplasias de la Mama/psicología , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Expansión de TejidoRESUMEN
INTRODUCTION: The European Society of Breast Cancer Specialists has created quality indicators for breast units to establish minimum standards and to ensure specialist multimodality care with the conscious aim of improving outcomes and decreasing breast cancer mortality. AIM: The aim of this study was to analyse the breast cancer care in the National Institute of Oncology according to the European Society of Breast Cancer Specialists requirements and in a large number of cases in order to present representative clinico-pathological data on the incidence of breast cancer in Hungary. METHOD: According to the European Society of Breast Cancer Specialists uniformed criteria clinico-pathological data of multimodality treated breast cancer cases were retrospectively analysed between June 1, 2011 and May 31, 2012. RESULTS: During the period of interest 906 patients underwent breast surgery for malignant or benign lesions. According to the European Society of Breast Cancer Specialists quality indicators the breast cancer care of the National Institute of Oncology is eligible. CONCLUSIONS: The diagnostic modalities and multimodality care of breast cancer of the National Institute of Oncology breast unit meets the critical mass and minimum standards of the European Society of Breast Cancer Specialists criteria. Orv. Hetil., 2016, 157(42), 1674-1682.
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Benchmarking/normas , Neoplasias de la Mama/terapia , Instituciones Oncológicas/normas , Calidad de la Atención de Salud/normas , Unión Europea , Humanos , Hungría , Estudios Retrospectivos , Nivel de AtenciónRESUMEN
CONTEXT: Pelvic region pressure sores often develop following spinal cord injury. Surgery is often necessary for long standing, large-sized pressure sores not responding to conservative treatment. Authors analyze their results of a 10-year period, and identify factors contributing to the reduction of the recurrence rate. METHODS: A total of 119 pressure sores were operated on 98 patients in two institutions during a 10-year period (1 January 2003 to 31 December 2012). The encountered perioperative complications are summarized, and the recurrence rate is analyzed with a patient follow-up questionnaire. RESULTS: We experienced 15 perioperative complications (12.6%). All complications were fully resolved by conservative treatment. Fifty-eight returned patient replies were processed. The average follow-up time after surgery was 5.2 years. The recurrence rate was 5.47%. CONCLUSION: The strict adherence to surgical indications, full patient compliance, specialized pre- and post-operative patient care, our routinely used preferred surgical method, all contribute to a low post-operative complication rate, long-term flap survival, and an extended recurrence free period.
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Pelvis/cirugía , Úlcera por Presión/cirugía , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pelvis/patología , Úlcera por Presión/etiología , Trasplante de Piel/efectos adversos , Traumatismos de la Médula Espinal/complicacionesRESUMEN
The increasing concentrations of CO2 in the atmosphere are attributed to the rising consumption of fossil fuels for energy generation around the world. One of the most stable and environmentally benign methods of reducing atmospheric CO2 is by storing it as thermodynamically stable carbonate minerals. Olivine ((Mg,Fe)2SiO4) is an abundant mineral that reacts with CO2 to form Mg-carbonate. The carbonation of olivine can be enhanced by injecting solutions containing CO2 at high partial pressure into olivine-rich formations at high temperatures, or by performing ex situ mineral carbonation in a reactor system with temperature and pressure control. In this study, the effects of NaHCO3 and NaCl, whose roles in enhanced mineral carbonation have been debated, were investigated in detail along with the effects of temperature, CO2 partial pressure and reaction time for determining the extent of olivine carbonation and its associated chemical and morphological changes. At high temperature and high CO2 pressure conditions, more than 70% olivine carbonation was achieved in 3 hours in the presence of 0.64 M NaHCO3. In contrast, NaCl did not significantly affect olivine carbonation. As olivine was dissolved and carbonated, its pore volume, surface area and particle size were significantly changed and these changes influenced subsequent reactivity of olivine. Thus, for both long-term simulation of olivine carbonation in geologic formations and the ex situ reactor design, the morphological changes of olivine during its reaction with CO2 should be carefully considered in order to accurately estimate the CO2 storage capacity and understand the mechanisms for CO2 trapping by olivine.
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Intermediate-depth earthquakes, at depths of 50-300 km in subduction zones, occur below the brittle-ductile transition, where high pressures render frictional failure unlikely. Their location approximately coincides with 600 to 800 degrees C isotherms in thermal models, suggesting a thermally activated mechanism for their origin. Some earthquakes may occur by frictional failure owing to high pore pressure that might result from metamorphic dehydration. Because some intermediate-depth earthquakes occur approximately 30 to 50 km below the palaeo-sea floor, however, the hydrous minerals required for the dehydration mechanism may not be present. Here we present an alternative mechanism to explain such earthquakes, involving the onset of highly localized viscous creep in pre-existing, fine-grained shear zones. Our numerical model uses olivine flow laws for a fine-grained, viscous shear zone in a coarse-grained, elastic half space, with initial temperatures from 600-800 degrees C and background strain rates of 10(-12) to 10(-15) s(-1). When shear heating becomes important, strain rate and temperature increase rapidly to over 1 s(-1) and 1,400 degrees C. The stress then drops dramatically, followed by low strain rates and cooling. Continued far-field deformation produces a quasi-periodic series of such instabilities.
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Carbonated serpentinites (listvenites) in the Samail Ophiolite, Oman, record mineralization of 1-2 Gt of CO2, but the mechanisms providing permeability for continued reactive fluid flow are unclear. Based on samples of the Oman Drilling Project, here we show that listvenites with a penetrative foliation have abundant microstructures indicating that the carbonation reaction occurred during deformation. Folded magnesite veins mark the onset of carbonation, followed by deformation during carbonate growth. Undeformed magnesite and quartz overgrowths indicate that deformation stopped before the reaction was completed. We propose deformation by dilatant granular flow and dissolution-precipitation assisted the reaction, while deformation in turn was localized in the weak reacting mass. Lithostatic pore pressures promoted this process, creating dilatant porosity for CO2 transport and solid volume increase. This feedback mechanism may be common in serpentinite-bearing fault zones and the mantle wedge overlying subduction zones, allowing massive carbonation of mantle rocks.
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This text is based on the recommendations accepted by the 4th Hungarian Consensus Conference on Breast Cancer, modified on the basis of the international consultation and conference within the frames of the Central-Eastern European Academy of Oncology. The recommendations cover non-operative, intraoperative and postoperative diagnostics, determination of prognostic and predictive markers and the content of cytology and histology reports. Furthermore, they address some specific issues such as the current status of multigene molecular markers, the role of pathologists in clinical trials and prerequisites for their involvement, and some remarks about the future.
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Neoplasias de la Mama , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Femenino , Humanos , Hungría , Mastectomía , Oncología Médica , PronósticoRESUMEN
The Perseverance rover landed in Jezero crater, Mars, in February 2021. We used the Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) instrument to perform deep-ultraviolet Raman and fluorescence spectroscopy of three rocks within the crater. We identify evidence for two distinct ancient aqueous environments at different times. Reactions with liquid water formed carbonates in an olivine-rich igneous rock. A sulfate-perchlorate mixture is present in the rocks, which probably formed by later modifications of the rocks by brine. Fluorescence signatures consistent with aromatic organic compounds occur throughout these rocks and are preserved in minerals related to both aqueous environments.
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Processes for formation, cooling, and altering Earth's ocean crust are not yet completely understood due to challenges in access and sampling. Here, we use contiguous micro-imaging infrared spectroscopy to develop complete-core maps of mineral occurrence and investigate spatial patterns in the hydrothermal alteration of 1.2 km of oceanic crust recovered from Oman Drilling Project Holes GT1A, GT2A, and GT3A drilled in the Samail Ophiolite, Oman. The imaging spectrometer shortwave infrared sensor measured reflectance of light at wavelengths 1.0-2.6 µm at 250-260 µm/pixel, resulting in >1 billion independent measurements. We map distributions of nine key primary and secondary minerals/mineral groups-clinopyroxene, amphibole, calcite, chlorite, epidote, gypsum, kaolinite/montmorillonite, prehnite, and zeolite-and find differences in their spatial occurrences and pervasiveness. Accuracy of spectral mapping of occurrence is 68%-100%, established using X-ray diffraction measurements from the core description. The sheeted dikes and gabbros of upper oceanic crust Hole GT3A show more pervasive alteration and alteration dominated by chlorite, amphibole, and epidote. The foliated/layered gabbros of GT2A from intermediate crustal depths have similarly widespread chlorite but more zeolite and little amphibole and epidote. The layered gabbros of the lower oceanic crust (GT1A) have remnant pyroxene and 2X less chlorite, but alteration is extensive within and surrounding major fault zones with widespread occurrences of amphibole. The results indicate greater distribution of higher temperature alteration minerals in the upper oceanic crust relative to deeper gabbros and highlight the importance of fault zones in hydrothermal convection in the lower ocean crust.
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Visible-shortwave infrared (VSWIR) imaging spectrometers map composition remotely with spatial context, typically at many meters-scale from orbital and airborne data. Here, we evaluate VSWIR imaging spectroscopy capabilities at centimeters to sub-millimeter scale at the Samail Ophiolite, Oman, where mafic and ultramafic lithologies and their alteration products, including serpentine and carbonates, are exposed in a semi-arid environment, analogous to similar mineral associations observed from Mars orbit that will be explored by the Mars-2020 rover. At outcrop and hand specimen scales, VSWIR spectroscopy (a) identifies cross-cutting veins of calcite, dolomite, magnesite, serpentine, and chlorite that record pathways and time-order of multiple alteration events of changing fluid composition; (b) detects small-scale, partially altered remnant pyroxenes and localized epidote and prehnite that indicate protolith composition and temperatures and pressures of multiple generations of faulting and alteration, respectively; and (c) discriminates between spectrally similar carbonate and serpentine phases and carbonate solid solutions. In natural magnesite veins, minor amounts of ferrous iron can appear similar to olivine's strong 1-µm absorption, though no olivine is present. We also find that mineral identification for carbonate and serpentine in mixtures with each other is strongly scale- and texture-dependent; â¼40 area% dolomite in mm-scale veins at one serpentinite outcrop and â¼18 area% serpentine in a calcite-rich travertine outcrop are not discriminated until spatial scales of <â¼1-2 cm/pixel. We found biological materials, for example bacterial mats versus vascular plants, are differentiated using wavelengths <1 µm while shortwave infrared wavelengths >1 µm are required to identify most organic materials and distinguish most mineral phases.
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Patients with relapsed/refractory chronic lymphocytic leukemia (R/R CLL) whose treatment failed with a Bruton's tyrosine kinase inhibitor have poor outcomes. We investigated tafasitamab plus idelalisib (cohort A) or venetoclax (cohort B) in this patient population in a phase II study (NCT02639910). In total, 24 patients were enrolled (cohort A: n = 11, median time on study, 7.4 months; cohort B: n = 13, median time on study, 15.6 months). The most common treatment-emergent adverse event (TEAE) in cohort A was anemia (63.6%) and in cohort B was infusion-related reaction (53.8%). The most common severe TEAE was neutropenia (cohort A: 45.5%; cohort B: 46.2%). The best overall response rate was 90.9% (cohort A) and 76.9% (cohort B). Undetectable minimal residual disease in peripheral blood was achieved in 2/8 patients (cohort A) and 6/7 patients (cohort B). Overall, these results suggest that anti-CD19 antibody-based combinations may be important in the treatment of patients with CLL.
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Leucemia Linfocítica Crónica de Células B , Linfoma de Células B , Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Compuestos Bicíclicos Heterocíclicos con Puentes/efectos adversos , Humanos , Leucemia Linfocítica Crónica de Células B/diagnóstico , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/efectos adversos , Purinas , Quinazolinonas , SulfonamidasRESUMEN
To avoid dangerous climate change, new technologies must remove billions of tonnes of CO2 from the atmosphere every year by mid-century. Here we detail a land-based enhanced weathering cycle utilizing magnesite (MgCO3) feedstock to repeatedly capture CO2 from the atmosphere. In this process, MgCO3 is calcined, producing caustic magnesia (MgO) and high-purity CO2. This MgO is spread over land to carbonate for a year by reacting with atmospheric CO2. The carbonate minerals are then recollected and re-calcined. The reproduced MgO is spread over land to carbonate again. We show this process could cost approximately $46-159 tCO2-1 net removed from the atmosphere, considering grid and solar electricity without post-processing costs. This technology may achieve lower costs than projections for more extensively engineered Direct Air Capture methods. It has the scalable potential to remove at least 2-3 GtCO2 year-1, and may make a meaningful contribution to mitigating climate change.
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The surgical treatment is still the most effective method in curing of early breast cancer. Breast preservation and the application of oncoplastic principles became generally accepted, the sentinel lymph node biopsy in the surgical treatment of the axilla is primary, and the indication for axillary block dissection (ABD) is narrowing further. The neoadjuvant oncological treatment that is applied more and more widely presented surgery with new challenges. Hereunder we summarise our recommendations on the surgical treatment of breast cancer based on the content of the 3rd Breast Cancer Consensus Conference and considering the latest international studies and professional recommendations.