cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.8259539
title: Bleeding risk of small intracranial aneurysms in a population treated in a reference center

description: ABSTRACT Large multicenter studies have shown that small intracranial aneurysms are associated with a minimal risk of bleeding. Nevertheless, other large series have shown that most ruptured aneurysms are, in fact, the smaller ones. In the present study, we questioned whether small aneurysms are indeed not dangerous. Methods: We enrolled 290 patients with newly-diagnosed aneurysms at our institution over a six-year period (43.7% ruptured). We performed multivariate analyses addressing epidemiological issues, cardiovascular diseases, and three angiographic parameters (largest aneurysm diameter, neck diameter and diameter of the nutrition vessel). Risk estimates were calculated using a logistic regression model. Aneurysm size parameters were stratified according to receiver operating characteristic (ROC) curves. Finally, we calculated odds ratios for rupture based on the ROC analysis. Results: The mean largest diameter for the ruptured versus unruptured groups was 13.3 ± 1.7 mm versus 22.2 ± 2.2 mm (p &lt; 0.001). Multivariate analysis revealed a positive correlation between rupture and arterial hypertension (p &lt; 0.001) and an inverse correlation with all three angiographic measurements (all p &lt; 0.01). Aneurysms from the anterior cerebral artery bled more often (p &lt; 0.05). According to the ROC curves, at the largest diameter of 15 mm, the sensitivity and specificity to predict rupture were 83% and 36%, respectively. Based on this stratification, we calculated the chance of rupture for aneurysms smaller than 15 mm as 46%, which dropped to 25% for larger aneurysms. Conclusion: In the population studied at our institution, small aneurysms were more prone to bleeding. Therefore, the need for intervention for small aneurysms should not be overlooked.
DOI: 10.6084/m9.figshare.8259539.v1
title: Bleeding risk of small intracranial aneurysms in a population treated in a reference center

description: ABSTRACT Large multicenter studies have shown that small intracranial aneurysms are associated with a minimal risk of bleeding. Nevertheless, other large series have shown that most ruptured aneurysms are, in fact, the smaller ones. In the present study, we questioned whether small aneurysms are indeed not dangerous. Methods: We enrolled 290 patients with newly-diagnosed aneurysms at our institution over a six-year period (43.7% ruptured). We performed multivariate analyses addressing epidemiological issues, cardiovascular diseases, and three angiographic parameters (largest aneurysm diameter, neck diameter and diameter of the nutrition vessel). Risk estimates were calculated using a logistic regression model. Aneurysm size parameters were stratified according to receiver operating characteristic (ROC) curves. Finally, we calculated odds ratios for rupture based on the ROC analysis. Results: The mean largest diameter for the ruptured versus unruptured groups was 13.3 ± 1.7 mm versus 22.2 ± 2.2 mm (p &lt; 0.001). Multivariate analysis revealed a positive correlation between rupture and arterial hypertension (p &lt; 0.001) and an inverse correlation with all three angiographic measurements (all p &lt; 0.01). Aneurysms from the anterior cerebral artery bled more often (p &lt; 0.05). According to the ROC curves, at the largest diameter of 15 mm, the sensitivity and specificity to predict rupture were 83% and 36%, respectively. Based on this stratification, we calculated the chance of rupture for aneurysms smaller than 15 mm as 46%, which dropped to 25% for larger aneurysms. Conclusion: In the population studied at our institution, small aneurysms were more prone to bleeding. Therefore, the need for intervention for small aneurysms should not be overlooked.
DOI: 10.6084/m9.figshare.8259521
title: Acoustic analysis of Facades of Light Steel Framing and Flat Sheets

description: ABSTRACT Dry construction has been considered as a technological alternative to conventional construction systems, and in recent years, systems as Light Steel Frame and Drywall have been used on a larger scale in Brazil. These systems consist of structured panels by steel profiles, filled internally by an insulation wool and sealed with flat plates on internal and external faces. It was verified that, in Brazil, the most used slabs in the external closure of these panels are produced from Portland cement and fibers, and there are therefore commonly referred how fiber cement. In the China and the US, they have alternatives such as plates made with magnesium oxide, called flat magnesium plates, whose application has been incipient by the Brazilian work construction. The performance standardization for popular residential (NBR 15.575), it was proposed an acoustic analysis of these panels from a special prototype, adopting as variable the plane flat. The differences in air sound insulation evaluated from the measurement of the parameter D2m, nT as a function of frequency according to ISO 140-5 and the calculation of the parameter D2m, nT, w (ISO 717-1) were studied, having as criterion the NBR 15575-4. The results presented in this work demonstrated that the magnesium based flat plates can collaborate for a better sound insulation throughout the frequency range, with a gain of 4dB in the insulation compared to conventional fiber cement panels.
DOI: 10.6084/m9.figshare.8259524
title: Blends of sugarcane bagasse with the mango tree and cashew tree's pruning: properties characterization and investigation of their energy potentials

description: ABSTRACT The work shows the energy potential of blends of sugarcane bagasse with the mango tree and cashew tree's pruning. The samples were characterized by gross calorific value, density, proximate analysis (moisture, ash, volatile matter and fixed carbon), elemental analysis and thermogravimetry. The blends were prepared with different mass fractions. After evaluation of the samples qualitative and quantitative analyses, it was verified which blends showed the better results and then the briquettes were prepared. The blends of sugarcane bagasse:mango tree pruning (fractions 50%:50%), sugarcane bagasse:cashew tree pruning (fractions 50%:50%), and sugarcane bagasse:cashew tree pruning:mango tree pruning (fractions 50%:25%:25%) were used to the briquettes production. The last part of the work shows the difference between the energy potential of the briquettes and the sugarcane bagasse. The energy density of the briquettes of sugarcane bagasse and mango tree pruning increased from 1.79 to 13.55 (kJ cm-3), in relation to the uncompacted material. The cashew tree pruning's briquettes varied from 1.97 to 12.75 (kJ cm-3), and the briquettes of sugarcane bagasse:cashew tree pruning:mango tree pruning varied from 2.46 to 12.18 (kJ cm-3). The sugarcane bagasse briquette showed a variation of 1.25 to 13.22 (kJ cm-3). The investigation of the energy potential of agricultural bioproducts (mango and cashew tree's pruning) in mixture with sugarcane bagasse presents to the sugar-alcohol industry a new possibility of reuse of biomass waste to obtain of energy.
DOI: 10.6084/m9.figshare.8259524.v1
title: Blends of sugarcane bagasse with the mango tree and cashew tree's pruning: properties characterization and investigation of their energy potentials

description: ABSTRACT The work shows the energy potential of blends of sugarcane bagasse with the mango tree and cashew tree's pruning. The samples were characterized by gross calorific value, density, proximate analysis (moisture, ash, volatile matter and fixed carbon), elemental analysis and thermogravimetry. The blends were prepared with different mass fractions. After evaluation of the samples qualitative and quantitative analyses, it was verified which blends showed the better results and then the briquettes were prepared. The blends of sugarcane bagasse:mango tree pruning (fractions 50%:50%), sugarcane bagasse:cashew tree pruning (fractions 50%:50%), and sugarcane bagasse:cashew tree pruning:mango tree pruning (fractions 50%:25%:25%) were used to the briquettes production. The last part of the work shows the difference between the energy potential of the briquettes and the sugarcane bagasse. The energy density of the briquettes of sugarcane bagasse and mango tree pruning increased from 1.79 to 13.55 (kJ cm-3), in relation to the uncompacted material. The cashew tree pruning's briquettes varied from 1.97 to 12.75 (kJ cm-3), and the briquettes of sugarcane bagasse:cashew tree pruning:mango tree pruning varied from 2.46 to 12.18 (kJ cm-3). The sugarcane bagasse briquette showed a variation of 1.25 to 13.22 (kJ cm-3). The investigation of the energy potential of agricultural bioproducts (mango and cashew tree's pruning) in mixture with sugarcane bagasse presents to the sugar-alcohol industry a new possibility of reuse of biomass waste to obtain of energy.
DOI: 10.6084/m9.figshare.8259521.v1
title: Acoustic analysis of Facades of Light Steel Framing and Flat Sheets

description: ABSTRACT Dry construction has been considered as a technological alternative to conventional construction systems, and in recent years, systems as Light Steel Frame and Drywall have been used on a larger scale in Brazil. These systems consist of structured panels by steel profiles, filled internally by an insulation wool and sealed with flat plates on internal and external faces. It was verified that, in Brazil, the most used slabs in the external closure of these panels are produced from Portland cement and fibers, and there are therefore commonly referred how fiber cement. In the China and the US, they have alternatives such as plates made with magnesium oxide, called flat magnesium plates, whose application has been incipient by the Brazilian work construction. The performance standardization for popular residential (NBR 15.575), it was proposed an acoustic analysis of these panels from a special prototype, adopting as variable the plane flat. The differences in air sound insulation evaluated from the measurement of the parameter D2m, nT as a function of frequency according to ISO 140-5 and the calculation of the parameter D2m, nT, w (ISO 717-1) were studied, having as criterion the NBR 15575-4. The results presented in this work demonstrated that the magnesium based flat plates can collaborate for a better sound insulation throughout the frequency range, with a gain of 4dB in the insulation compared to conventional fiber cement panels.
DOI: 10.6084/m9.figshare.8259512
title: Predictive value of transcranial doppler ultrasound for cerebral small vessel disease in elderly patients

description: ABSTRACT Objective: To investigate the predictive value of transcranial Doppler (TCD) ultrasound for cerebral small vessel disease in elderly patients. Methods: Transcranial Doppler ultrasound and magnetic resonance imaging (MRI) were performed on 184 elderly patients with cerebral small vessel disease. The relationship of clinical characteristics and TCD ultrasound parameters with severe white matter lesions (WMLs) in MRI were investigated by univariate analysis and multivariate analysis. Results: The univariate analysis showed that age, left middle cerebral artery (MCA) mean flow velocity, right MCA mean flow velocity and mean MCA pulsatility index were significantly correlated with severe WMLs (p &lt; 0.05). The multivariate logistic regression analysis showed that only age (odds ratio: 1.21; 95%CI: 1.10–1.36; p &lt; 0.01) and MCA pulsatility index (dominance ratio: 1.13; 95%CI: 1.06–1.80; p = 0.02) were significantly correlated with severe WMLs. The analysis of TCD ultrasound parameters showed that when the cut-off for MCA pulsatility index was 1.04, it could identify severe WMLs. The area under the curve was 0.70 (95%CI: 0.60–0.80). The sensitivity and specificity were 63.0% and 72.0%, respectively. The positive and negative predictive values were 35.4% and 86.6%, respectively. Conclusion: The MCA pulsatility index in TCD ultrasound is significantly correlated with severe WMLs; and TCD ultrasound can guide selective MRI for the detection of WMLs.
DOI: 10.6084/m9.figshare.8259515
title: Long-term behavior of mortars produced with sulfide-bearing aggregates

description: ABSTRACT The variety of sulfides (inorganic compounds formed by combining sulfur with a metal element) present in earth crust is not small, which makes it difficult to avoid the use of sulfide-bearing aggregates in the concrete, especially in places where another source of material is non-existent or economically impracticable, as is the case of dams in Brazil. Within this scenario, this work presents an evaluation of the long-term behavior of mortar produced with aggregates containing pyrite and pyrrhotite. For the study, rock samples from the Irapé Hydroelectric Power Plant area in Minas Gerais (Brazil) were used. This plant was built in a geological site where the rock presented sulfide levels of at least 3%. These rock samples were first ground and then used as aggregates in mortars, which were, during almost 1300 days, subjected to three different exposed conditions: 1-temperature of 23° ± 2°C and relative humidity of 95 to 100%; 2-submerged in calcium hydroxide solution diluted in water almost 850 days and then kept in water up to 1300 days, both in room temperature; 3-submerged in calcium hydroxide solution diluted in water at 50° C during almost 850 days and then kept in water (50° C) up to 1300 days. The presence and amount of pyrrhotite were obtained from a leaching process of the material (aggregate or mortar) in a solution of hydrochloric acid. This procedure allowed also the evaluation of the pyrite content. The results showed that the calcium hydroxide solution speeds up the expansion just like the temperature. It was also observed that the amount of pyrite has remained virtually constant over time in the three exposure situations. This finding indicates that sulfur limits in aggregates should be set according to the type of iron sulfide presented and not only by the total amount of sulfur.
DOI: 10.6084/m9.figshare.8259509
title: Micropropagation and Cellular Behaviour Changes During in vitro Flowering of Impatiens balsamina

description: ABSTRACT: In this study, the micropropagation of Impatiens balsamina was established from stem and shoot explants. The effects of GA3 and glutathione on the morphogenesis of this species were also investigated, in order to induce in vitro flowering. It was found that the optimum in vitro plant regeneration was achieved on MS medium supplemented with 1.0 mg L-1 GA3 and in vitro flowering was also obtained from the same medium after 4 weeks of culture. To understand cellular behavior during in vitro flowering, Mitotic Index (MI), chromosome counts, measurement of mean cell and nuclear areas, DNA measurements and ploidy levels were analyzed from in vivo plants, in vitro grown plants and plantlets that flowered in vitro. The chromosome count was the same for all, 2x=2n=14 or n=7. However, it was observed that in vitro flowering plants of Impatiens balsamina had the highest percentage of polyploid cells (30.7%), based on a histogram plotted by the AxioVision 4.7 software. It was found that plant growth regulators, especially GA3, increased the polyploidy level of the meristematic root cells.
DOI: 10.6084/m9.figshare.8259512.v1
title: Predictive value of transcranial doppler ultrasound for cerebral small vessel disease in elderly patients

description: ABSTRACT Objective: To investigate the predictive value of transcranial Doppler (TCD) ultrasound for cerebral small vessel disease in elderly patients. Methods: Transcranial Doppler ultrasound and magnetic resonance imaging (MRI) were performed on 184 elderly patients with cerebral small vessel disease. The relationship of clinical characteristics and TCD ultrasound parameters with severe white matter lesions (WMLs) in MRI were investigated by univariate analysis and multivariate analysis. Results: The univariate analysis showed that age, left middle cerebral artery (MCA) mean flow velocity, right MCA mean flow velocity and mean MCA pulsatility index were significantly correlated with severe WMLs (p &lt; 0.05). The multivariate logistic regression analysis showed that only age (odds ratio: 1.21; 95%CI: 1.10–1.36; p &lt; 0.01) and MCA pulsatility index (dominance ratio: 1.13; 95%CI: 1.06–1.80; p = 0.02) were significantly correlated with severe WMLs. The analysis of TCD ultrasound parameters showed that when the cut-off for MCA pulsatility index was 1.04, it could identify severe WMLs. The area under the curve was 0.70 (95%CI: 0.60–0.80). The sensitivity and specificity were 63.0% and 72.0%, respectively. The positive and negative predictive values were 35.4% and 86.6%, respectively. Conclusion: The MCA pulsatility index in TCD ultrasound is significantly correlated with severe WMLs; and TCD ultrasound can guide selective MRI for the detection of WMLs.
DOI: 10.6084/m9.figshare.8259515.v1
title: Long-term behavior of mortars produced with sulfide-bearing aggregates

description: ABSTRACT The variety of sulfides (inorganic compounds formed by combining sulfur with a metal element) present in earth crust is not small, which makes it difficult to avoid the use of sulfide-bearing aggregates in the concrete, especially in places where another source of material is non-existent or economically impracticable, as is the case of dams in Brazil. Within this scenario, this work presents an evaluation of the long-term behavior of mortar produced with aggregates containing pyrite and pyrrhotite. For the study, rock samples from the Irapé Hydroelectric Power Plant area in Minas Gerais (Brazil) were used. This plant was built in a geological site where the rock presented sulfide levels of at least 3%. These rock samples were first ground and then used as aggregates in mortars, which were, during almost 1300 days, subjected to three different exposed conditions: 1-temperature of 23° ± 2°C and relative humidity of 95 to 100%; 2-submerged in calcium hydroxide solution diluted in water almost 850 days and then kept in water up to 1300 days, both in room temperature; 3-submerged in calcium hydroxide solution diluted in water at 50° C during almost 850 days and then kept in water (50° C) up to 1300 days. The presence and amount of pyrrhotite were obtained from a leaching process of the material (aggregate or mortar) in a solution of hydrochloric acid. This procedure allowed also the evaluation of the pyrite content. The results showed that the calcium hydroxide solution speeds up the expansion just like the temperature. It was also observed that the amount of pyrite has remained virtually constant over time in the three exposure situations. This finding indicates that sulfur limits in aggregates should be set according to the type of iron sulfide presented and not only by the total amount of sulfur.
DOI: 10.6084/m9.figshare.8259506
title: Fatigue failure analysis of HSLA steel sheets holed by conventional and flow drilling processes

description: ABSTRACT Flow drilling process produces bushes for removable joints that can be threaded by forming tapping process, reducing stages in production of components of automobile industry and in construction sheds. High strength and low alloy steels (HSLA) are employed on several applications in the processing industry. Benefits provided by these materials make them an efficient solution, since their high cold resistance allows reducing weight on structures, as well as maintaining the required mechanical properties. The present study evaluated the conventional and friction drilling processes in HSLA steel sheets with a thickness of 4.25 mm. Specimens were subjected to cyclic loadings, with no rework after holemaking, so the resultant characteristics of each process were maintained. Fractured surfaces were analyzed with a scanning electron microscope (SEM) to identify the fracture mechanism in different drilling processes. Fractographies obtained on both processes indicated that the failure mechanism occurred due to ductile fracture resulting from the nucleation, growth and coalescence of micro cavities.
DOI: 10.6084/m9.figshare.8259503
title: Agate waste valorization in mortars and concretes: life cycle assessment

description: ABSTRACT The application of residues from agate beneficiation process (agate powder) in mortars and concretes based on Portland cement is technically viable considering materials mechanical properties and durability. However, there is a lack of studies that assess the environmental profile of the produced materials. This paper aims to evaluate the potential environmental impacts associated to the life cycle of mortars and concretes produced with the application of agate powder in substitution of Portland cement and fine aggregate, respectively. To that, experimental designs defined in previous studies were considered, to perform a cradle to gate analysis, where the following impacts were evaluated, according to CML-IA method: climate change, soil and water acidification, eutrophication, ozone layer depletion, and resources depletion (fossil and non-fossil). Results show up to 30% reduction of potential impacts, for the application of the residue in substitution to Portland cement in mortars. Less expressive reductions are observed for the use of the residue in substitution of the fine aggregate; however, gains on mechanical strength justify the application of the residue in specific cases. Since all the assessed impacts are closely related to cement consumption, the application of the residue to replace cement is considered the most environmentally viable alternative, for the evaluated cases. The participation of the transport processes in all impact categories validates the application of materials locally produced/extracted. Finally, future studies shall consider the performance of the produced materials, in comparison to the reference ones.
DOI: 10.6084/m9.figshare.8259500
title: Influence of Crystallization and Ageing Time on the Reproducibility of Mesoporous Molecular Sieve SBA-15

description: ABSTRACT The study aimed to assess how the crystallization and ageing times in SBA-15 synthesis influence the reproducibility and particle size of mesoporous molecular sieves. X-ray diffraction showed that higher crystallization times provide greater reproducibility of mesoporous silica, due to the fact that there is no significant variation in the width and intensity of peaks, while the same is not true for shorter crystallization times. Ageing time does not seem to exercise a significant influence when higher crystallization times are used in the synthesis. Scanning electron microscopy observations revealed that shorter crystallization times led to larger crystals in addition to the formation of large agglomerates, whereas with higher crystallization times the trend is to obtain smaller and more uniform grains. It is proposed that hydrogen bonds may be responsible for the formation of smaller particles and it is also established that depending on the synthesis conditions the reproducibility of the process can become low.