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The precise detection of the toxic gas H2 S requires reliable sensitivity and specificity of sensors even at minute concentrations of as low as 10â ppm, the value corresponding to typical exposure limits. CuO can be used for H2 S dosimetry, based on the formation of conductive CuS and the concomitant significant increase in conductance. In theory, at elevated temperature the reaction is reversed and CuO is formed, ideally enabling repeated and long-term use of one sensor. Yet, the performance of CuO tends to drop upon cycling. Utilizing defined CuO nanorods we thoroughly elucidated the associated detrimental chemical changes directly on the sensors, by Raman and electron microscopy analysis of each step during sensing (CuOâCuS) and regeneration (CuSâCuO) cycles. We find the decrease in the sensing performance is mainly caused by the irreversible formation of CuSO4 during regeneration. The findings allowed us to develop strategies to reduce CuSO4 formation and thus to substantially maintain the sensing stability even for repeated cycles. We achieved CuO-based dosimeters possessing a response time of a few minutes only, even for 10â ppm H2 S, and prolonged life-time.
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Cobre , NanotubosRESUMO
This study examined the relation between Internet pornography use and narcissism. Participants (N=257) completed an online survey that included questions on Internet pornography use and 3 narcissism measures (i.e., Narcissistic Personality Inventory, Pathological Narcissistic Inventory, and the Index of Sexual Narcissism). The hours spent viewing Internet pornography was positively correlated to participants' narcissism level. In addition, those who have ever used Internet pornography endorsed higher levels of all 3 measures of narcissism than did those who have never used Internet pornography.
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Literatura Erótica/psicologia , Internet/estatística & dados numéricos , Narcisismo , Autoimagem , Disfunções Sexuais Psicogênicas/psicologia , Rede Social , Feminino , Humanos , Masculino , Inquéritos e QuestionáriosRESUMO
Internet pornography (IP) consumption has increased, resulting in functioning and psychological problems. Thus, understanding what variables affect IP uses is needed. One of the variables may be religion. College students (N = 223) completed questions on IP use and religion. About 64 % ever viewed IP and 26 % currently viewed IP, at a rate of 74 min per week. IP use interfered with their relationship with God and spirituality. Religious individuals were less likely to ever or currently view IP. Intrinsic and extrinsic religiosity and alignment of spiritual values were associated with ever use. Results suggest that religiosity matters in IP use and further research is needed.
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Literatura Erótica/psicologia , Internet , Religião e Psicologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Inquéritos e Questionários , Adulto JovemRESUMO
Due to its intense use of resources, the construction sector was identified as a priority sector in the European Green Deal. Construction and demolition waste (CDW) is one of the largest waste streams of the European Union. As it shows a high potential for recycling, the European Commission set a recovery target of 70% under the Waste Framework Directive. To control the performance and achievements of the member states, annual national reports to the EU are required. However, there exist different ways to specify and report these rates. Recovery rates published by EUROSTAT are calculated on the basis of waste treatment data of non-hazardous mineral CDW, generated according to the EU Waste Statistics Regulation. Limiting factors like non-unified methods of data collection, different waste coding systems and misinterpretations of the term 'backfilling' impede a cross-country comparison of the published EU recovery rates. In this study, factors that may have a misleading impact on reporting EUROSTAT CDW recovery rates were compiled and a detailed analysis using national quality reports of twelve selected EU countries as a data base were performed. The development of the reported recycling rates over five years was examined and the influence of the various factors was determined. The findings may enhance a more purposeful (scientific) discussion of CDW data and for evidence-based reporting of national recovery rates, and may assist the development towards an improved, uniform EU-wide data set. Finally, this will provide support to decision makers for future policy and governmental requirements.
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Indústria da Construção , Gerenciamento de Resíduos , União Europeia , Indústria da Construção/métodos , Materiais de Construção , Conservação dos Recursos Naturais , Reciclagem/métodos , Gerenciamento de Resíduos/métodos , Resíduos Industriais/análiseRESUMO
Luminomagnetic composites have been synthesized that allow for an individual tuning of luminescence intensity, chromaticity and magnetization by combination of superparamagnetic, citrate-stabilized iron oxide nanoparticles with the luminescent MOFs 3 ∞ [Ln2 (BDC)3 (H2 O)4 ] (Ln=Eu, Tb; BDC2- =terephthalate). The components are arranged to a concept of inverse structuring compared to previous luminomagnetic composites with MOF@magnetic particle (shell@core) composition so that the luminescent MOF now acts as core and is covered by magnetic nanoparticles forming the satellite shell. Thereby, the magnetic and photophysical properties are individually tuneable between high emission intensity (1.2 â 106 â cps mg-1 ) plus low saturation magnetization (6â emu g-1 ) and the direct opposite (0.09 â 106 â cps mg-1 ; 42â emu g-1 ) by adjusting the particle coverage of the MOF. This is not achievable with a core-shell structure having a magnetic core and a dense MOF shell. The composition of the composites and the influence of different synthesis conditions on their properties were investigated by SEM/EDX, PXRD, magnetization measurements and photoluminescence spectroscopy.
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Quaternary climatic changes have been invoked as important drivers of species diversification worldwide. However, the impact of such changes on vegetation and animal population dynamics in tropical regions remains debated. To overcome this uncertainty, we integrated high-resolution paleoenvironmental reconstructions from a sedimentary record covering the past 25,000 years with demographic inferences of a forest-dwelling primate species (Microcebus arnholdi), in northern Madagascar. Result comparisons suggest that climate changes through the African Humid Period (15.2 - 5.5 kyr) strongly affected the demographic dynamics of M. arnholdi. We further inferred a population decline in the last millennium which was likely shaped by the combination of climatic and anthropogenic impacts. Our findings demonstrate that population fluctuations in Malagasy wildlife were substantial prior to a significant human impact. This provides a critical knowledge of climatically driven, environmental and ecological changes in the past, which is essential to better understand the dynamics and resilience of current biodiversity.
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Cheirogaleidae/fisiologia , Ecossistema , Animais , Madagáscar , Dinâmica PopulacionalRESUMO
Understanding long-term environmental changes under natural and anthropic forces is helpful for facilitating sustainable development. Here we present a sedimentary record from the central Tibetan Plateau to investigate the impacts of climate and human activities on alpine vegetation during the late Holocene, based on a 162-cm-long lacustrine sediment core collected from Tangra Yumco. Palynology, charcoal and minerogenic input reveal variations of climate and human activity during the past 3400 cal yr BP. Our results show that alpine steppe dominated by Artemisia, Cyperaceae and Poaceae was present in the Tangra Yumco area during the entire covered period. Only minor human activities are visible between 3400 and 2300 as well as from 1700 to 400 cal yr BP, when vegetation was mainly influenced by climate. Although human activities (presence/grazing) became more intensive between 2300 and 1700 cal yr BP corresponding to the Zhang Zhung Kingdom, vegetation change is still mainly affected by a more arid climate. Strongest human influence on vegetation was found after 400 cal yr BP, when vegetation composition was altered by farming and grazing activities. Our records indicate human activities did not have significant impacts on alpine environment until the past few centuries at Tangra Yumco on the central Tibetan Plateau.
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PURPOSE: To compare intraindividual higher-order wavefront aberrations after implantation of aspherical and spherical intraocular lenses (IOLs) as function of pupil diameter. SETTING: Department of Ophthalmology, Johann Wolfgang Goethe-University, Frankfurt am Main, Germany. METHODS: In this prospective study, wavefront measurements of 21 patients after implantation of a spherical IOL (AMO AR40e) in 1 eye and an aspherical IOL (AMO Tecnis) in the contralateral eye were analyzed. Third-, 4th-, 5th-, total higher-order aberration (HOA) root-mean-square (RMS), and primary spherical aberration (Z(4)(0)) were compared at different virtual pupil diameters of 3 to 6 mm. RESULTS: For both IOLs and each higher order analyzed, values increased with increasing pupil diameter. Fourth-order RMS and Z(4)(0) in the aspherical IOL group were significantly lower than with the spherical IOL at all analyzed pupil diameters. The total HOA RMS of the aspherical IOL was significantly lower than the spherical IOL only at 6 mm pupil diameter. For 3rd- and 5th-order RMS, no significant difference was found between the tested IOLs at any pupil diameter. CONCLUSION: In comparison to a spherical IOL, the aspherical Tecnis IOL reduced Z(4)(0) and 4th-order RMS significantly for pupil diameters of 3 to 6 mm, whereas total HOA RMS was only significantly reduced for a pupil diameter of 6 mm.
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Implante de Lente Intraocular/efeitos adversos , Lentes Intraoculares , Pupila/fisiologia , Erros de Refração/etiologia , Idoso , Idoso de 80 Anos ou mais , Topografia da Córnea , Humanos , Pessoa de Meia-Idade , Facoemulsificação , Estudos Prospectivos , Desenho de Prótese , Refração Ocular , Acuidade VisualRESUMO
PURPOSE: To intraindividually compare visual performance in terms of photopic high-contrast visual acuity (HCVA), mesopic HCVA, mesopic low-contrast visual acuity (LCVA), and contrast sensitivity (CS) in patients after implantation of either an aspherical or a spherical intraocular lens (IOL). SETTING: Department of Ophthalmology, Johann Wolfgang Goethe-University, Frankfurt am Main, Germany. METHODS: Forty eyes of 20 patients were randomized to implantation of an aspherical IOL (Tecnis Z9000, AMO) in 1 eye and a spherical IOL (Sensar AR40e, AMO) in the other eye. Three to 4 months postoperatively, photopic HCVA (270 cd/m(2)) was measured with the observer-independent Frankfurt-Freiburg Contrast and Acuity Test System (FF-CATS) and high-mesopic HCVA and LCVA (8 cd/m(2)) were measured with Early Treatment Diabetic Retinopathy Study charts. CS was assessed with the FF-CATS under photopic (167 cd/m(2)), high-mesopic (1.67 cd/m(2)), and low-mesopic (0.167 cd/m(2)) luminance conditions with and without glare. For each individual eye, higher-order wavefront aberrations were reconstructed for a physiological mesopic pupil diameter. Intraindividual differences (Delta(i)) in visual acuity, contrast sensitivity, and higher-order aberrations (HOAs) were calculated, and the influence of age and Delta(i) HOA on Delta(i) contrast sensitivity (logCS) under high-mesopic conditions was investigated using multiple regression analysis. RESULTS: There were no statistically significant differences between the Tecnis IOL and the Sensar IOL in visual acuity measurements or contrast sensitivity measurements. For physiological mesopic pupil diameter, primary spherical aberration (Z(4)(0)) was significantly lower in the Tecnis group (P<.001). For all parameters studied except Z(4)(0), the Delta(i) values were distributed around zero. Multiple regression analysis showed only a partial influence of Delta(i) Z(4)(0) on Delta(i) logCS (adjusted R(2) = 0.49) but did not show any influence of age, coma-like aberration, or residual HOA. CONCLUSIONS: Although Z(4)(0) was significantly lower in the eyes with the aspherical IOL, no statistically significant differences were found between aspherical and spherical IOLs in LCVA, HCVA, and contrast sensitivity. Statistical analysis of intraindividual contrast sensitivity differences showed that in most patients, this Z(4)(0) difference was too low to have an effect on contrast sensitivity.
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Sensibilidades de Contraste/fisiologia , Lentes Intraoculares , Pseudofacia/fisiopatologia , Erros de Refração/fisiopatologia , Acuidade Visual/fisiologia , Idoso , Idoso de 80 Anos ou mais , Ofuscação , Humanos , Implante de Lente Intraocular , Pessoa de Meia-Idade , Facoemulsificação , Complicações Pós-Operatórias , Desenho de PróteseRESUMO
PURPOSE: To determine incision sizes for 6-mm optic foldable intraocular lenses (IOLs) implanted with injector systems. DESIGN: Nonrandomized, prospective clinical study. PARTICIPANTS: One hundred fifty eyes of 150 patients with cataract and without other anterior segment pathological features or previous eye surgeries. INTERVENTION: We performed implantation of foldable IOLs with sharp optic edges and 6-mm total optic diameter with their recommended injector systems and cartridges: (1) Alcon MA60BM with Monarch II/cartridge A, (2) Alcon SA60AT with Monarch II/cartridge B, (3) Alcon SA60AT with Monarch II/cartridge C, (4) AMO AR40e with Unfolder Sapphire, (5) AMO AR40e with Unfolder Emerald, and (6) AMO Clariflex with Unfolder Silver. With every combination, 25 IOLs were implanted. MAIN OUTCOME MEASURES: We measured incision width before and after phacoemulsification as well as before and after IOL implantation using a Kohnen caliper. RESULTS: The tunnel width (in millimeters; +/- standard deviation) for each combination before and after IOL implantation, respectively, was (1) 3.61 (+/-0.12) and 3.74 (+/-0.15), (2) 3.31 (+/-0.12) and 3.44 (+/-0.16), (3) 2.88 (+/-0.11) and 2.96 (+/-0.11), (4) 3.37 (+/-0.12) and 3.52 (+/-0.09), (5) 2.99 (+/-0.16) and 3.11 (+/-0.14), and (6) 3.06 (+/-0.12) and 3.15 (+/-0.11). The incision sizes before and after implantation for (3) were significantly smaller than all other combinations. Combinations (2) and (4) were not statistically significantly different, but were statistically significantly smaller in preimplantation and postimplantation incision size compared with combination (1) and were larger compared with combinations (5) and (6). However, the relationship of incision size and effective IOL optical zone differed: AR40e (Unfolder Sapphire) < MA60BM < Clariflex < AR40e (Unfolder Emerald) < SA60AT with both Monarch II B and C cartridge (greater means better relationship). CONCLUSIONS: Postimplantation incisions sizes of 2.96 to 3.74 mm were determined with 6-mm total optic foldable IOLs using Monarch and Unfolder injector systems. Because the effective optical zone size is different for some of these IOLs, the incision size alone may not be the only relevant factor for optical outcome.
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Implante de Lente Intraocular/métodos , Lentes Intraoculares , Facoemulsificação/métodos , Técnicas de Sutura , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Implante de Lente Intraocular/instrumentação , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
The Tibetan Plateau (TP) is primarily influenced by the northern hemispheric middle latitude Westerlies and the Indian summer monsoon (ISM). The extent, long-distance effects and potential long-term changes of these two atmospheric circulations are not yet fully understood. Here, we analyse modern airborne pollen in a transition zone of seasonally alternating dominance of the Westerlies and the ISM to develop a pollen discrimination index (PDI) that allows us to distinguish between the intensities of the two circulation systems. This index is applied to interpret a continuous lacustrine sedimentary record from Lake Nam Co covering the past 24 cal kyr BP to investigate long-term variations in the atmospheric circulation systems. Climatic variations on the central TP widely correspond to those of the North Atlantic (NA) realm, but are controlled through different mechanisms resulting from the changing climatic conditions since the Last Glacial Maximum (LGM). During the LGM, until 16.5 cal kyr BP, the TP was dominated by the Westerlies. After 16.5 cal kyr BP, the climatic conditions were mainly controlled by the ISM. From 11.6 to 9 cal kyr BP, the TP was exposed to enhanced solar radiation at the low latitudes, resulting in greater water availability.
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In 1992, a ciliary sulcus-fixated, silicone, phakic posterior chamber intraocular lens (PPC IOL) (Adatomed, Fyodorov type) was implanted in both eyes of a 42-year-old white woman to correct high myopia (right eye, -17.0 diopters [D]; left eye, -11.5 D). In the right eye, localized cortical opacification was present in the anterior part of the natural lens preoperatively but did not progress during a 10-year follow-up period. With Scheimpflug photography, it was possible to detect a space between the natural lens and the IOL that was not evident on slitlamp examination. Maintenance of space between an IOL and the natural lens appears to be an important factor in preventing cataract formation after PPC IOL implantation.
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Corpo Ciliar/cirurgia , Implante de Lente Intraocular/métodos , Cristalino/fisiologia , Lentes Intraoculares , Miopia/cirurgia , Elastômeros de Silicone , Catarata/prevenção & controle , Feminino , Seguimentos , Humanos , Cristalino/anatomia & histologia , Pessoa de Meia-Idade , Fotografação , SegurançaRESUMO
PURPOSE: To compare 2 infrared pupillometers with a videokeratographer and 2 aberrometers for the determination of scotopic pupil size. SETTING: Department of Ophthalmology, Johann Wolfgang Goethe-University, Frankfurt am Main, Germany. METHODS: The pupil diameter was measured in 100 eyes of 51 patients after 2 minutes of dark adaptation using the following devices: digital infrared pupillometer (Procyon Instruments Ltd.), handheld infrared pupillometer (Colvard) (Oasis Medical), Zywave aberrometer (Bausch & Lomb), Wasca aberrometer (Asclepion-Meditec-Zeiss), and Orbscan II topography system (Bausch & Lomb Surgical). Measurements taken with the Procyon pupillometer were considered reference values for comparison with the other devices. Statistical evaluation was performed using the Bland-Altmann method for comparison of measurement techniques. RESULTS: The mean pupil size was 6.10 mm +/- 0.86 (SD) with the Procyon pupillometer, 5.68 +/- 1.07 mm with the Colvard pupillometer, 5.91 +/- 1.01 mm with the Zywave aberrometer with the fixating target turned off, 5.09 +/- 1.14 mm with the Zywave aberrometer with the fixating target turned on, 5.59 +/- 0.99 mm with the Wasca aberrometer, and 3.75 +/- 0.67 mm with the Orbscan topographer. The limits of agreement were smallest for measurements between Procyon and Colvard and largest for measurements between Procyon and Orbscan. The sign test revealed statistically significant differences for all devices compared with the Procyon pupillometer (P<.001 in all cases) except the Zywave aberrometer with the fixating target turned off (P=.13). CONCLUSIONS: The Zywave wavefront sensor with the fixating target turned off using the study settings and light conditions provided measurements of scotopic pupil diameter that were closest to the reference values (Procyon). With the other devices (Colvard pupillometer, Zywave aberrometer with the fixating target switched on, Wasca aberrometer, and Orbscan topographer), the difference was statistically significant.
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Técnicas de Diagnóstico Oftalmológico/normas , Iris/anatomia & histologia , Pupila , Adulto , Pesos e Medidas Corporais , Adaptação à Escuridão , Técnicas de Diagnóstico Oftalmológico/instrumentação , Humanos , Raios Infravermelhos , Pessoa de Meia-Idade , Fotografação/instrumentação , Cuidados Pré-Operatórios , Procedimentos Cirúrgicos Refrativos , Reprodutibilidade dos Testes , Gravação em VídeoRESUMO
BACKGROUND: Vitreoretinal complications are rare in laser in situ keratomileusis (LASIK). Increase in intraocular pressure caused by intraoperative suction with subsequent deforming of the ocular globe and excimer laser shock during the ablation have been discussed as possible causes. The purpose of this study was to determine the effect of LASIK on the vitreous body. PATIENTS AND METHODS: In a prospective study we performed ocular ultrasonography (B scan) immediately before and 1 week after LASIK procedure in 103 myopic or myopic-astigmatic eyes (53 patients, mean age 36.3 years, 32 women, 21 men). In particular, the prevalence, localization, and extent of posterior vitreous detachment (PVD) were determined. RESULTS: The mean spherical equivalent was -4.85 D (range -1.25 to -8.38) and the mean anteroposterior ocular globe length was 25.13 mm (range 23.31-27.65). Ninety-five eyes (92.2%) had no PVD preoperatively. Nine eyes out of this group (seven patients, 9.5%) developed incomplete PVD as assessed 1 week postoperatively. Eight eyes (7.8%) had a partial PVD preoperatively and in only one eye was an extension of vitreous detachment observed after the surgery. None of the preoperatively measured parameters could predict the occurrence of PVD by LASIK. CONCLUSIONS: LASIK may in rare cases lead to new occurrence of PVD or extension of a previously existing partial PVD.