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Protected area (PA) is an indicator linked to policies on ecological sustainability. We analyzed area, size, and categories of PAs in the European boreal forest biome in Norway, Sweden, Finland, and Russia from 1900 to 2010. The PA increased from 1.5 × 10(3) ha in 1909 to 2.3 × 10(7) ha in 2010. While the total PA in the boreal biome was 10.8 %, the figures ranged from 17.2 % in the northern, 7.9 % of the middle, and 8.7 % of the southern boreal sub-regions. The median size of PAs varied from 10 to 124 ha among countries. The categories of less strictly PAs increased over time. The proportion of area occupied by PAs is an important response indicator for conservation efforts. However, the use of PA as an indicator of ecological sustainability needs to consider ecosystem representation, functional connectivity and management categories.
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Conservación de los Recursos Naturales/tendencias , Agricultura Forestal , Ecosistema , Europa (Continente) , ÁrbolesRESUMEN
Identification of multiphase inclusions in peridotite suggests that released carbon from a subducting slab can be stored as diamond+methane+magnesite in the overlying mantle wedge, achieving deep carbon cycling.
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Most natural diamonds are formed in Earth's lithospheric mantle; however, the exact mechanisms behind their genesis remain debated. Given the occurrence of electrochemical processes in Earth's mantle and the high electrical conductivity of mantle melts and fluids, we have developed a model whereby localized electric fields play a central role in diamond formation. Here, we experimentally demonstrate a diamond crystallization mechanism that operates under lithospheric mantle pressure-temperature conditions (6.3 and 7.5 gigapascals; 1300° to 1600°C) through the action of an electric potential applied across carbonate or carbonate-silicate melts. In this process, the carbonate-rich melt acts as both the carbon source and the crystallization medium for diamond, which forms in assemblage with mantle minerals near the cathode. Our results clearly demonstrate that electric fields should be considered a key additional factor influencing diamond crystallization, mantle mineral-forming processes, carbon isotope fractionation, and the global carbon cycle.
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Diamonds and their inclusions are unique fragments of deep Earth, which provide rare samples from inaccessible portions of our planet. Inclusion-free diamonds cannot provide information on depth of formation, which could be crucial to understand how the carbon cycle operated in the past. Inclusions in diamonds, which remain uncorrupted over geological times, may instead provide direct records of deep Earth's evolution. Here, we applied elastic geothermobarometry to a diamond-magnesiochromite (mchr) host-inclusion pair from the Udachnaya kimberlite (Siberia, Russia), one of the most important sources of natural diamonds. By combining X-ray diffraction and Fourier-transform infrared spectroscopy data with a new elastic model, we obtained entrapment conditions, Ptrap = 6.5(2) GPa and Ttrap = 1125(32)-1140(33) °C, for the mchr inclusion. These conditions fall on a ca. 35 mW/m2 geotherm and are colder than the great majority of mantle xenoliths from similar depth in the same kimberlite. Our results indicate that cold cratonic conditions persisted for billions of years to at least 200 km in the local lithosphere. The composition of the mchr also indicates that at this depth the lithosphere was, at least locally, ultra-depleted at the time of diamond formation, as opposed to the melt-metasomatized, enriched composition of most xenoliths.
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Diamond is a material of immense technological importance and an ancient signifier for wealth and societal status. In geology, diamond forms as part of the deep carbon cycle and typically displays a highly ordered cubic crystal structure. Impact diamonds, however, often exhibit structural disorder in the form of complex combinations of cubic and hexagonal stacking motifs. The structural characterization of such diamonds remains a challenge. Here, impact diamonds from the Popigai crater were characterized with a range of techniques. Using the MCDIFFaX approach for analysing X-ray diffraction data, hexagonality indices up to 40% were found. The effects of increasing amounts of hexagonal stacking on the Raman spectra of diamond were investigated computationally and found to be in excellent agreement with trends in the experimental spectra. Electron microscopy revealed nanoscale twinning within the cubic diamond structure. Our analyses lead us to propose a systematic protocol for assigning specific hexagonality attributes to the mineral designated as lonsdaleite among natural and synthetic samples.
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PURPOSE: To compare the concentrations of interleukin (IL) (IL-1b, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70), interferon (IFN)-γ, tumor necrosis factor (TNF)-α, and TNF-ß in the aqueous humor of patients undergoing femtosecond laser-assisted cataract surgery (FLACS) and corneal mechanical paracentesis treated with two different topical nonsteroidal anti-inflammatory drugs (NSAIDs): bromfenac and indomethacin. METHODS: In this prospective, randomized controlled, single-center study, aqueous humor samples were obtained immediately after performing the femtosecond laser procedure or at the start of conventional phacoemulsification. Preoperatively, the FLACS groups were administered (once daily and four times daily, respectively) either topical bromfenac 0.09% (12 eyes) or indomethacin 0.1% (12 eyes). The corneal paracentesis bromfenac and indomethacin groups received the same regimen of instillation of NSAIDs, respectively. Quantitative analysis of the expressed cytokines in the aqueous humor was performed using FlowCytomix FC 500 Pro 3.0 Software (Bender MedSystems GmbH, Vienna, Austria). RESULTS: The intraoperative pupil diameter was correlated with the expression of IL-6 after the femtosecond laser procedure in the FLACS indomethacin group (r = -0.53; P = .07). A significant difference in mean pupillary size was detected between the FLACS bromfenac and indomethacin groups at the aspiration/irrigation time point (0.53 ± 0.26 mm) and at the end of surgery (0.68 ± 0.37 mm). Progressive pupillary constriction was observed in the indomethacin and bromfenac groups. CONCLUSIONS: A smaller expression of IL-6 to the overall cytokine network value was observed in cases receiving preoperative bromfenac 0.09%, explaining improved maintenance of intraoperative mydriasis. [J Refract Surg. 2018;34(10):646-652.].
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Antiinflamatorios no Esteroideos/administración & dosificación , Humor Acuoso/metabolismo , Citocinas/metabolismo , Terapia por Láser , Facoemulsificación , Pupila/efectos de los fármacos , Administración Oftálmica , Anciano , Benzofenonas/administración & dosificación , Bromobencenos/administración & dosificación , Extracción de Catarata/métodos , Femenino , Humanos , Indometacina/administración & dosificación , Masculino , Persona de Mediana Edad , Soluciones Oftálmicas/administración & dosificación , Estudios ProspectivosRESUMEN
We describe a case of femtosecond laser-assisted cataract surgery (FLACS) in an eye with multiple comorbidities, including retinal detachment surgery, high myopia, posterior chamber phakic intraocular lens (PC pIOL) and residual, emulsified, silicone oil located in the anterior chamber. FLACS was affected by the optical blockage, but the incomplete capsular tear was recoverable. The case suggests that silicone oil bubbles concentrated at the dome of the posterior corneal surface, along with the PC pIOL optic edges and scars after corneal astigmatic relaxing incisions can lead to incomplete anterior capsulotomy.
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Extracción de Catarata/métodos , Terapia por Láser/métodos , Lentes Intraoculares Fáquicas , Adulto , Humanos , Masculino , Desprendimiento de Retina/cirugía , Aceites de Silicona/administración & dosificación , Resultado del Tratamiento , VitrectomíaRESUMEN
PURPOSE: To describe a case of femtosecond laser-assisted hydrophobic intraocular lens transection. METHODS: Case report. RESULTS: Femtosecond laser-assisted transection of a one-piece acrylic hydrophobic intraocular lens for explantation via a small surgical incision was successfully performed with low energy parameters. CONCLUSIONS: This case illustrates a novel and effective clinical application of the femtosecond laser. [J Refract Surg. 2017;33(9):646-648.].
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Cápsula Anterior del Cristalino/cirugía , Extracción de Catarata/efectos adversos , Remoción de Dispositivos/métodos , Terapia por Láser/métodos , Lentes Intraoculares/efectos adversos , Complicaciones Posoperatorias/cirugía , Refracción Ocular , Adulto , Cápsula Anterior del Cristalino/diagnóstico por imagen , Extracción de Catarata/métodos , Estudios de Seguimiento , Humanos , Masculino , Complicaciones Posoperatorias/diagnóstico por imagen , Tomografía de Coherencia ÓpticaRESUMEN
UNLABELLED: We developed a surgical technique that combines use of an iris hook and a pupil expansion ring in femtosecond laser-assisted cataract surgery complicated by insufficient mydriasis and an ectopic pupil. With this technique, the surgery, including femtosecond laser assistance, phacoemulsification, and intraocular lens implantation, can be accomplished successfully prior to iris repair. FINANCIAL DISCLOSURE: Dr. Malyugin receives travel grants from Alcon Laboratories, Inc. and Novartis Corp.; he receives royalties from Microsurgical Technology, Inc. None of the other authors has a financial or proprietary interest in any material or method mentioned.
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Catarata , Implantación de Lentes Intraoculares , Facoemulsificación , Pupila , Humanos , Midriasis , Trastornos de la PupilaRESUMEN
Analysis of data on micro- and nano-inclusions in mantle-derived and metamorphic diamonds shows that, to a first approximation, diamond-forming medium can be considered as a specific ultrapotassic, carbonate/chloride/silicate/water fluid. In the present work, the processes and mechanisms of diamond crystallization were experimentally studied at 7.5 GPa, within the temperature range of 1,400-1,800 degrees C, with different compositions of melts and fluids in the KCl/K(2)CO(3)/H(2)O/C system. It has been established that, at constant pressure, temperature, and run duration, the mechanisms of diamond nucleation, degree of graphite-to-diamond transformation, and formation of metastable graphite are governed chiefly by the composition of the fluids and melts. The experimental data suggest that the evolution of the composition of deep-seated ultrapotassic fluids/melts is a crucial factor of diamond formation in mantle and ultrahigh-pressure metamorphic processes.