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1.
Article in English | MEDLINE | ID: mdl-38477149

ABSTRACT

OBJECTIVE: This study aimed to externally and prospectively validate the International Ovarian Tumor Analysis (IOTA) Simple Rules (SRs), Logistic Regression model 2 (LR2) and Assessment of Different NEoplasias in the adneXa (ADNEX) in a Portuguese population, comparing them with operator subjective assessment (SA), Risk-of-Malignancy Index (RMI), as well as with each other. This study also aimed to retrospectively validate IOTA two-step strategy, using modified benign descriptors (MBDs) followed by the application of ADNEX in cases where MBDs were not applicable (MBDs + ADNEX). METHODS: In this multicenter diagnostic accuracy study, conducted between January 2016 and December 2021, three tertiary referral centers prospectively included consecutive patients with ultrasound diagnosis of at least one adnexal tumor who underwent surgery. All ultrasound assessments were performed by level II or III sonologists with IOTA certification. Patient clinical data and serum cancer antigen (CA125) levels were collected from the hospital databases. Each adnexal mass was classified as benign or malignant using SA, RMI, IOTA SRs, LR2 and ADNEX (with and without CA125). The reference standard was histopathological diagnosis. In the second phase, all adnexal tumors were retrospectively classified using the two-step strategy (MBDs + ADNEX). The sensitivity, specificity, positive (PPV) and negative predictive value (NPV), positive (LR+) and negative likelihood ratio (LR-) as well as overall accuracy were determined for SA, RMI, IOTA SRs, LR2, ADNEX and two-step strategy (MBDs + ADNEX). Receiver-operator characteristic curves were constructed and corresponding areas under the curve (AUC) determined for RMI, LR2 and ADNEX and two-step strategy (MBDs + ADNEX). The ADNEX calibration plots were constructed and estimated by LOESS smoother. RESULTS: Of the 571 included patients, 428 had benign disease, 42 borderline ovarian tumors, 93 primary invasive adnexal cancers and 8 metastatic tumors in adnexa (malignancy prevalence: 25.0%). The operator SA had an overall sensitivity of 97.9% and a specificity of 83.6% for distinguishing between benign and malignant lesions. RMI showed high specificity (95.6%) but very low sensitivity (58.7%), with an AUC of 0.913. The IOTA SRs were applicable in 80.0% of patients, with a sensitivity of 94.8% and a specificity of 98.6%. LR2 revealed a sensitivity of 84.6%, a specificity of 86.9% and an AUC of 0.939, at the malignancy risk cut-off of 10%. At the same cut-off, ADNEX with and without CA125 had a sensitivity of 95.8% and 98.6%, respectively, and a specificity of 82.5% and 79.7%, respectively. The AUC of ADNEX with vs. without CA125 was 0.962 vs. 0.960. The ADNEX model provided heterogeneous results in distinguishing between benign and different subtypes of malignancy, with the highest AUC (0.991) for discriminating benign masses from primary adnexal cancer stage II-IV, and the lowest AUC (0.696) for distinguishing primary adnexal cancer stage I and metastatic lesion in adnexa. The ADNEX calibration plots suggested an underestimation of the predicted risk in relation with the observed proportion of malignancies. The MBDs were applicable in 26.3% of cases (150/571 tumors, none of which were malignant). Similar to the ADNEX model applied in all patients, the two-step strategy using ADNEX in the second step only, with and without CA125, had an AUC of 0.964 and 0.961, respectively. CONCLUSIONS: Our results showed a good to excellent performance of the IOTA methods in the studied Portuguese population, outperforming RMI. ADNEX was superior in accuracy, but interpretation of its ability to distinguish malignant subtypes was fundamentally limited not only by sample size but also by large differences in the prevalence of tumor subtypes. The IOTA MBDs have been shown to be reliable in identifying benign disease. The two-step strategy based on the application of MBDs, followed by the ADNEX model if MBDs are not applicable, has proven to be suitable for daily practice circumventing the need to use electronic support in all patients. This article is protected by copyright. All rights reserved.

2.
J Mech Behav Biomed Mater ; 119: 104438, 2021 07.
Article in English | MEDLINE | ID: mdl-33798936

ABSTRACT

OBJECTIVE: To evaluate the failure probability and stress distribution of traditional and bioinspired porcelain-zirconia milled crowns, with and without silica infiltration (graded zirconia). METHODS: Traditional crown design had a zirconia infrastructure veneered with porcelain; Bioinspired, had a porcelain infrastructure with translucent-zirconia veneer; Graded and Graded Bioinspired crowns had their zirconia layer infiltrated by silica (n = 25). The cameo surface of each crown (porcelain or zirconia) was glazed. The restoration layers were fused by a vitreous connector and the crowns were adhesively cemented to dies. The specimens were then mechanically cycled in a sliding machine using 100 N load at 4 Hz. The specimens were tested until 2 × 106 cycles, and every 0.5 × 106 cycles the crowns were evaluated under stereomicroscopy for the presence of failures. The stress distribution was inspected with Finite Element Analyses. RESULTS: The predominant failure modes for the Traditional and Graded crowns were delamination and cracking, respectively. The Weibull parameters beta and eta were, respectively: Traditional 1.30 and 2.3 × 106 cycles, and Graded 1.95 and 2.3 × 106 cycles. Thus, the Traditional and Graded crowns presented greater susceptibility to failure due to fatigue, while the Bioinspired and Graded Bioinspired crowns showed no fatigue effect using 100N load, showing beta = 1 and eta of approximately 17 × 106 cycles. Also, through finite element analyses, it was verified that the Bioinspired and Graded Bioinspired crowns presented the best stress distribution on both crowns and dental structures. SIGNIFICANCE: Bioinspired and Graded Bioinspired crowns had the lowest failure probability and better stress distribution and may be considered robust long lasting restorations.


Subject(s)
Dental Porcelain , Zirconium , Crowns , Dental Restoration Failure , Dental Stress Analysis , Dental Veneers , Materials Testing , Probability , Surface Properties
3.
Animal ; 14(S3): s438-s452, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32778195

ABSTRACT

Accurate estimates of methane (CH4) production by cattle in different contexts are essential to developing mitigation strategies in different regions. We aimed to: (i) compile a database of CH4 emissions from Brazilian cattle studies, (ii) evaluate prediction precision and accuracy of extant proposed equations for cattle and (iii) develop specialized equations for predicting CH4 emissions from cattle in tropical conditions. Data of nutrient intake, diet composition and CH4 emissions were compiled from in vivo studies using open-circuit respiratory chambers, SF6 technique or the GreenFeed® system. A final dataset containing intake, diet composition, digestibility and CH4 emissions (677 individual animal observations, 40 treatment means) obtained from 38 studies conducted in Brazil was used. The dataset was divided into three groups: all animals (GEN), lactating dairy cows (LAC) and growing cattle and non-lactating dairy cows (GCNL). A total of 54 prediction equations available in the literature were evaluated. A total of 96 multiple linear models were developed for predicting CH4 production (MJ/day). The predictor variables were DM intake (DMI), gross energy (GE) intake, BW, DMI as proportion of BW, NDF concentration, ether extract (EE) concentration, dietary proportion of concentrate and GE digestibility. Model selection criteria were significance (P < 0.05) and variance inflation factor lower than three for all predictors. Each model performance was evaluated by leave-one-out cross-validation. The Intergovernmental Panel on Climate Change (2006) Tier 2 method performed better for GEN and GCNL than LAC and overpredicted CH4 production for all datasets. Increasing complexity of the newly developed models resulted in greater performance. The GCNL had a greater number of equations with expanded possibilities to correct for diet characteristics such as EE and NDF concentrations and dietary proportion of concentrate. For the LAC dataset, equations based on intake and animal characteristics were developed. The equations developed in the present study can be useful for accurate and precise estimation of CH4 emissions from cattle in tropical conditions. These equations could improve accuracy of greenhouse gas inventories for tropical countries. The results provide a better understanding of the dietary and animal characteristics that influence the production of enteric CH4 in tropical production systems.


Subject(s)
Diet , Lactation , Methane , Animal Feed/analysis , Animals , Brazil , Cattle , Diet/veterinary , Energy Intake , Female , Methane/analysis , Milk/chemistry
4.
Braz J Med Biol Res ; 53(8): e10034, 2020.
Article in English | MEDLINE | ID: mdl-32609258

ABSTRACT

Contradictory findings suggest that the behavioral and abuse-related effects of ethanol are mediated by its action at α1 subunit-containing GABAA (α1GABAA) receptors. In the present study, we investigated the effects of a sub-chronic post-ethanol administration treatment with zolpidem, an α1-preferring positive allosteric modulator at GABAA receptors, on the subsequent expression of ethanol-induced behavioral sensitization in mice. Animals received ethanol (1.8 g/kg, ip) or saline treatments every other day for 15 days (8 treatment sessions) and were subsequently treated with zolpidem (0.5 mg/kg, ip) or vehicle 4 times on alternate days. At the end of the treatment phase, animals were challenged with saline or ethanol on separate days for the evaluation of the expression of conditioned locomotion and behavioral sensitization. Eight-day treatment with ethanol did not lead to the development of ethanol-induced behavioral sensitization. Animals treated with ethanol and subsequently administered vehicle showed similar locomotion frequencies during the last ethanol challenge compared to the control group receiving ethanol for the first time. Animals treated with ethanol and subsequently administered zolpidem expressed behavioral sensitization to ethanol during the ethanol challenge. The present study adds to the literature by providing further evidence of a role of α1GABAA receptors on the behavioral effects of ethanol. Because of the current highly prevalent co-abuse of ethanol and benzodiazepine drugs in humans, the use of zolpidem and other α1GABAA receptor ligands during ethanol withdrawal should be monitored carefully.


Subject(s)
Ethanol , GABA-A Receptor Agonists/pharmacology , Zolpidem/pharmacology , Animals , Benzodiazepines , Locomotion , Male , Mice , Receptors, GABA-A
5.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 243-252, Jan.-Feb. 2020. tab
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1088938

ABSTRACT

O objetivo deste estudo foi avaliar o perfil de ácidos graxos (AG) do leite de vacas alimentadas com dietas à base de silagem de milho contendo 0% e 8,9% de glicerina bruta (GB) na matéria seca (MS). Foram utilizadas 18 vacas Holandês x Gir com 48±18 dias em lactação, produzindo 19,8±4,9kg/dia de leite. Utilizou-se delineamento de blocos ao acaso, com nove vacas/tratamento e duas medidas repetidas no tempo, com os resultados analisados por modelos mistos. A inclusão de GB na dieta não alterou a ingestão de MS, mas reduziu os consumos dos AG oleico, linoleico e α-linolênico. Os teores dos AG mirístico, palmítico, rumênico, vacênico, esteárico, oleico, linoleico, α-linolênico e CLA trans-10 cis-12 na gordura do leite foram semelhantes entre dietas. A inclusão de GB reduziu os teores dos AG elaídico e C18:1 trans-10 e aumentou os teores dos AG de cadeia ímpar linear e do ácido láurico. Não houve efeito da inclusão da GB sobre os índices de aterogenicidade e trombogenicidade da gordura do leite. Concluiu-se que a inclusão de glicerina bruta em dieta à base de silagem de milho não afetou a qualidade nutricional da gordura do leite de vacas Holandês x Gir.(AU)


The objective of this study was to evaluate the milk fatty acid (FA) composition of cows fed corn silage-based diets containing 0% and 8.9% of crude glycerin (GB) on a dry matter (DM) basis. Eighteen Holstein x Gyr cows with 48±18 days in milk and producing 19.8±4.9kg milk/day were used in the study. The experimental design was a randomized block with nine cows per treatment and two repeated measures. Results were analyzed using mixed models. The milk fat contents of myristic, palmitic, rumenic, vaccenic, estearic, oleic, linoleic, α-linolenic, and trans-10 cis-12 CLA were similar between diets. Dietary inclusion of GB decreased elaidic and trans-10 C18:1, and increased lauric acid and odd linear-chain FA contents in milk fat. Both atherogenicity and trombogenicity indices were unaffected by GB inclusion. It was concluded that GB inclusion in corn silage-based diets had no effect on the nutritional quality of milk fat from Holstein x Gyr dairy cows.(AU)


Subject(s)
Animals , Female , Cattle , Silage , Milk/chemistry , Fatty Acids/analysis , Glycerol/administration & dosage , Biofuels , Animal Feed
6.
Eur J Prosthodont Restor Dent ; 28(1): 10-17, 2020 Feb 27.
Article in English | MEDLINE | ID: mdl-31638348

ABSTRACT

PURPOSE: The present study evaluated the displacement and strain generated in an implant- supported fixed prosthesis under axial and non-axial loads using two methods. MATERIALS AND METHODS: Three implants were inserted in a resin block. The Digital Image Correlation (DIC) was used to measure displacement and strain generated on the surface of the resin blocks for the different load applications (500N, 1 image/second). A 3-dimensional model was constructed and a load of 500 N was applied at an axial point and a non-axial point through finite element analysis (FEA). RESULTS: Both methods gave similar trends for the strains, and both gave slightly higher strains with non-axial loading. FEA predicted higher strain magnitude (±11%) in comparison with DIC, but with the same mechanical behavior. According to ANOVA, the loading influenced the strain concentration. Higher strain was generated for non-axial loading around the implant nearest to the loading. CONCLUSIONS: For implant-retained cantilever fixed prosthesis, the same load applied in the lever arm induces higher strain in the cervical area of the last implant, which suggests more damaging potential than a load applied at the center of the prosthesis.


Subject(s)
Dental Implants , Dental Prosthesis, Implant-Supported , Biomechanical Phenomena , Dental Prosthesis Design , Dental Stress Analysis , Finite Element Analysis , Stress, Mechanical
7.
Braz. j. med. biol. res ; 53(8): e10034, 2020. graf
Article in English | LILACS, Coleciona SUS | ID: biblio-1132538

ABSTRACT

Contradictory findings suggest that the behavioral and abuse-related effects of ethanol are mediated by its action at α1 subunit-containing GABAA (α1GABAA) receptors. In the present study, we investigated the effects of a sub-chronic post-ethanol administration treatment with zolpidem, an α1-preferring positive allosteric modulator at GABAA receptors, on the subsequent expression of ethanol-induced behavioral sensitization in mice. Animals received ethanol (1.8 g/kg, ip) or saline treatments every other day for 15 days (8 treatment sessions) and were subsequently treated with zolpidem (0.5 mg/kg, ip) or vehicle 4 times on alternate days. At the end of the treatment phase, animals were challenged with saline or ethanol on separate days for the evaluation of the expression of conditioned locomotion and behavioral sensitization. Eight-day treatment with ethanol did not lead to the development of ethanol-induced behavioral sensitization. Animals treated with ethanol and subsequently administered vehicle showed similar locomotion frequencies during the last ethanol challenge compared to the control group receiving ethanol for the first time. Animals treated with ethanol and subsequently administered zolpidem expressed behavioral sensitization to ethanol during the ethanol challenge. The present study adds to the literature by providing further evidence of a role of α1GABAA receptors on the behavioral effects of ethanol. Because of the current highly prevalent co-abuse of ethanol and benzodiazepine drugs in humans, the use of zolpidem and other α1GABAA receptor ligands during ethanol withdrawal should be monitored carefully.


Subject(s)
Animals , Male , Rabbits , GABA Agonists/pharmacology , Ethanol , Zolpidem/pharmacology , Benzodiazepines , Receptors, GABA-A , Locomotion
8.
Eur J Prosthodont Restor Dent ; 27(2): 76-82, 2019 May 30.
Article in English | MEDLINE | ID: mdl-31046208

ABSTRACT

PURPOSE: This study evaluated the stress distribution in different cement-retained implant-supported prostheses with a hybrid abutment. MATERIALS AND METHODS: Two factors were evaluated: restorative material for the crown and hybrid abutment - zirconia, lithium disilicate and hybrid ceramic, yielding 9 combinations. For finite element analysis, a monolithic crown cemented on a hybrid abutment was modeled and cemented on a titanium base (Ti base). An oblique load (45°, 300 N) was applied to the fossa bottom and system fixation occurred on the bone's base. RESULTS: Each structure was evaluated separately to find the possible weaknesses in geometry and failure criteria. In this context, results demonstrated a significant decrease of maximum principal and von-Mises stresses concentration when crowns with high elastic modulus are cemented onto a hybrid abutment with lower elastic modulus. CONCLUSIONS: Considering this theoretical study for a Morse taper implant, the association of a rigid crown with a more resilient hybrid abutment reduces the tensile stress concentration in the restoration cervical region.


Subject(s)
Ceramics , Dental Prosthesis, Implant-Supported , Zirconium , Crowns , Dental Materials , Dental Stress Analysis , Finite Element Analysis , Stress, Mechanical
9.
Dent Mater ; 35(1): 64-73, 2019 01.
Article in English | MEDLINE | ID: mdl-30448347

ABSTRACT

OBJECTIVE: To evaluate the fatigue failure load via staircase approach and stress distribution via FEA of different ceramic configurations arranged in multilayers composed of ceramic materials with different elastic moduli and compare them to monolayer models. METHODS: CAD-CAM ceramic blocks were used to shape 0.3mm and 1.5mm thick discs, corresponding to: feldspathic (F), 64GPa; lithium disilicate (L), 95GPa; and Yttrium-partially stabilized tetragonal zirconia (Y-TZP) (Y), 209.3GPa. The 0.3mm discs were arranged in 4 layers cemented with resin cement (Multilink N), and the 1.5mm discs were not treated, in such a way that the final thickness of all specimens was 1.5mm (±0.15mm). The following 6 groups were tested: F (F: monolithic); L (L: monolithic); LLFF (L+L+F+F); FFLL (F+F+L+L); YLFF (Y+L+F+F); YLLF (Y+L+L+F). The loads-to-fracture were obtained using the biaxial flexural strength test until failure and the data were run using one-way ANOVA and Tukey's multiple comparisons (α=0.05) tests. The biaxial bending test was also simulated through finite element analysis (FEA) to identify the tensile stress generated at each layer of the groups. Mean fatigue failure load (100,000 cycles; 20Hz) was determined using the staircase approach. The fracture analysis was performed by stereomicroscope and scanning electron microscopy. RESULTS: The load to fracture (N) were obtained as follows: L (592.9±73.8)D>FFLL (319.78±43.59)C>YLLF (246.75±24.89)B>F (167.13±9.84)A>YLFF (166.51±15.24)A>LLFF (165.46±22.75)A; and the fatigue failure load (N): L (310.92±26.73)F>FFLL (190.17±8.32)E>F (106.21±2.81)D>YLLF (96.48±5.73)C>YLFF (89.56±2.38)B>LLFF (77.23±6.33)A. The origin of all of the tested specimens was located at the tensile region of the discs, as encountered in FEA. SIGNIFICANCE: The material under tensile stress is determinant for the restoration's strength and the adhesive interface negatively influenced the mechanical behavior of the multilayer structures.


Subject(s)
Ceramics , Dental Porcelain , Dental Stress Analysis , Fatigue , Finite Element Analysis , Humans , Materials Testing , Surface Properties , Zirconium
10.
Dent Mater ; 34(9): 1401-1409, 2018 09.
Article in English | MEDLINE | ID: mdl-29934124

ABSTRACT

OBJECTIVE: The goal of this study was to investigate the fatigue life, failure modes, and stress distribution of partial ultrafine restorations for posterior teeth in different ceramics. METHODS: Sixty standard tabletop preparations in epoxy resin G10 received lithium-silicate-based zirconia-reinforced (ZLS) or hybrid ceramic (PIC) restorations in 0.5- or 1-mm thickness bonded with resin cement. The same cycling protocol was applied for all specimens, which consisted of 5000 cycles at 200N, followed by 450-N cycles until the specimens' fracture or the suspension of the test after 1.5×106 cycles. Axial load was carried out with a 4Hz frequency in Biocycle V2 equipment (Biopdi, São Carlos, SP), with samples immersed in water. The presence of cracks and/or fractures was checked every 2.5×105 cycles, and the survival analysis was performed with the number of cycles in which each specimen failed. All specimens were evaluated by stereomicroscopy and scanning electron microscopy (SEM). After data tabulation, Kaplan-Meier and Mantel-Cox (log-rank test) analyses were performed, followed by multiple pairwise comparison, all with a significance level of 5%, and Weibull analysis. Through three-dimensional finite element analysis, stress distribution and maximum principal stresses in the posterior occlusal veneers were evaluated by comparison of different types of substrate (G10, enamel/dentin, enamel), thicknesses, and ceramic materials. RESULTS: Zirconium-reinforced lithium silicate restorations with 0.5-mm thickness (ZLS.5) showed lower fatigue strength compared with that of 1.0-mm hybrid ceramic restorations (PIC1), and both were similar to other restorations (PIC.5 and ZLS1) (log-rank test, χ2=11.2; df=3; p=0.0107<0.05). ZLS groups presented random defects that culminated in fracture, whereas PIC groups presented defects that increased with mechanical fatigue after some cycling time. Stereomicroscope images show radial cracks due to the translucency of the material. There was no damage caused by the applicator. MPS (maximum principal stress) distributions were similar for the different substrate types, but the highest modulus of elasticity showed slightly lower stress concentration. SIGNIFICANCE: PIC is more likely to be used in thinner thickness than indicated by the manufacturer, with fatigue strength similar to that of thicker ZLS restorations.


Subject(s)
Ceramics/chemistry , Dental Restoration Failure , Dental Materials/chemistry , Dental Porcelain/chemistry , Dental Stress Analysis , Elastic Modulus , Materials Testing , Microscopy, Electron, Scanning , Surface Properties , Zirconium/chemistry
11.
Arq. bras. med. vet. zootec. (Online) ; 70(3): 993-1003, maio-jun. 2018. tab
Article in Portuguese | LILACS, VETINDEX | ID: biblio-912073

ABSTRACT

Objetivou-se avaliar os efeitos do zinco ou do propilenoglicol sobre o desempenho e nas características da carcaça e da carne de ovinos sob pastejo em pastagem nativa da Caatinga. Utilizaram-se 24 ovinos, mestiços Santa Inês, machos, não castrados, peso inicial de 19,3±2,52kg, com quatro meses de idade, oito repetições por tratamento, distribuídos em um delineamento inteiramente ao acaso. Os tratamentos foram: sem aditivo, controle (CT), adição de sulfato de zinco (ZnSO4.7H2O) (Zn) para fornecimento de 300mg de Zn dia-1 via sal mineral, e propilenoglicol (PG), 2,5mL kgPC0,75-1 animal-1 dia-1 misturado no concentrado. Os animais foram suplementados com concentrado constituído de milho (54,0%), farelo de soja (45,1%) e calcário (0,911%) em 0,7% do PC médio de cada tratamento. O ensaio foi conduzido durante quatro meses (março a junho/2014). Avaliaram-se o desempenho e, após o abate dos animais, as características de carcaça e os componentes não carcaça, os parâmetros físico-químicos e organolépticos na carne. O Zn e o propilenoglicol não afetaram o desempenho e os parâmetros da carcaça em termos absoluto e relativo, bem como os pesos dos cortes e seus rendimentos (P>0,05). Não houve efeito dos aditivos nas características organolépticas e nos aspectos físico-químicos da carne (P>0,05), exceto cinzas (P<0,05). O zinco e o propilenoglicol não melhoram o desempenho e as características da carcaça de animais terminados em pastagem nativa da Caatinga. O baixo suprimento energético devido à má qualidade do pasto entre os meses de abril a junho contribui para a ineficiência no aproveitamento dos constituintes proteicos, implicando menor consumo e consequente diminuição do desempenho.(AU)


The aim was to evaluate the effects of zinc sulfate or propylene glycol on performance and carcass and meat characteristics from sheep under grazing in native Caatinga (Brazilian savannah) pasture during the rainy season. Twenty-four intact Santa Ines crossbreed male lambs, with an initial weight of 19.3±2.52kg, and 4-mo old, were distributed in a completely randomized design with eight replications per treatment. The treatments were composed of additives, as follows: no additive - control (CT); addition of zinc sulfate (ZnSO4.7H2O) (Zn) to supply a total of 300mg Zn day−1 on mineral salt; and addition of propylene glycol (PG), 2.5mL kg LW0.75−1 animal−1 day−1 mixed directly in the concentrate. Afterwards, they were supplemented with concentrate at 0.7% of the average LW of each batch according to the treatments. The concentrate was based on corn (54.0%), soybean meal (45.1%), and limestone (0.911%). The trials were carried out during the rainy season (March to June 2014), and evaluated the performance, and before of slaughter, carcass characteristics and non-carcass components were evaluated and the physical-chemical aspects and the organoleptic attributes on the meat. The additives did not affect the performance, parameters of carcass, in terms absolute and relative, carcass morphometric measurements, weight of the commercial cuts and yields (P>0.05). The additives did not affect the organoleptic characteristics and physical-chemical aspects of the meat (P>0.05), except, ash (P<0.05). The zinc sulfate and propylene glycol did not improve on performance and in carcass characteristics in lambs finished on a native Caatinga (Brazilian savannah) pasture. The low supply energetic due to poor quality of pasture between the months of April to June, which contributed to inefficiency in the utilization of proteics constituents, implying in lower intake, and decrease in performance.(AU)


Subject(s)
Animals , Infant Nutritional Physiological Phenomena , Pasture/analysis , Sheep/metabolism , Meat/statistics & numerical data
12.
Braz J Biol ; 75(3 Suppl 1): 222-37, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26691096

ABSTRACT

Among the studies on Orchidaceae in the Amazon, none comprised the region of the Great Curve of the Xingu River, located in the lower Xingu river. The aim of this study was to inventory and taxonomically study the species of Oncidiinae (Orchidaceae) in the Great Curve of the Xingu River, Pará state. The floristic survey was performed in the area of the Belo Monte hydroelectric plant, in the Vitória do Xingu municipality, centrally inserted in the called Great Curve of the Xingu River. Botanical collections were accomplished between June 2011 and December 2013. A total of 27 species of Oncidiinae, distributed in 15 genera, was inventoried in the study area. Notylia Lindl. and Trichocentrum Poepp. & Endl. were the richest genera, with five and four species, respectively, followed by Erycina Lindl., Ionopsis Kunth, Lockhartia Hook., Macradenia R.Br., and Ornithocephalus Hook., with two species each. The remaining eight genera are represented by a single species each in the study area. Morphological descriptions, a key for taxonomic identification, illustrations, and comments on distribution, ecology, phenology and morphology are provided for all inventoried species.


Subject(s)
Biodiversity , Orchidaceae/classification , Brazil , Ecosystem , Orchidaceae/anatomy & histology , Orchidaceae/physiology , Plant Dispersal
13.
Braz J Biol ; 75(3 Suppl 1): 238-49, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26691097

ABSTRACT

Microclimatic conditions of tropical forest favour the high richness of bryophytes, which by being sensitive to environmental changes, are important indicators of habitat conditions. The aim of this study was to determine the richness and species composition of the bryophyte flora in fragments of terra firme forest on the great curve of the Xingu River, Pará state, Brazil. The collections were made in August and September 2012 in 14 fragments, in which were installed two plots per fragment, one at the edge and one inside, measuring 10 × 10 m each. The results showed 77 species in 45 genera and 18 families. Lejeunea setiloba Spruce and Marchesinia brachiata (Sw.) Schiffn. are new records for Pará state. The richness families in this study were the ones typically found in tropical forest surveys. A high richness of rare species in comparison to common ones, a pattern usually observed for plants in tropical forests was not reported in this study, probably due to historical fragmentation and disturbance in the area. The richness and species composition were determined mainly by the physiognomic characteristics of the studied forest fragments.


Subject(s)
Biodiversity , Bryophyta/physiology , Forests , Brazil , Ecosystem , Plant Dispersal
14.
Braz. j. biol ; 75(3,supl.1): 222-237, Aug. 2015. graf
Article in English | LILACS, VETINDEX | ID: biblio-1468301

ABSTRACT

Among the studies on Orchidaceae in the Amazon, none comprised the region of the Great Curve of the Xingu River, located in the lower Xingu river. The aim of this study was to inventory and taxonomically study the species of Oncidiinae (Orchidaceae) in the Great Curve of the Xingu River, Pará state. The floristic survey was performed in the area of the Belo Monte hydroelectric plant, in the Vitória do Xingu municipality, centrally inserted in the called Great Curve of the Xingu River. Botanical collections were accomplished between June 2011 and December 2013. A total of 27 species of Oncidiinae, distributed in 15 genera, was inventoried in the study area. Notylia Lindl. and Trichocentrum Poepp. & Endl. were the richest genera, with five and four species, respectively, followed by Erycina Lindl., Ionopsis Kunth, Lockhartia Hook., Macradenia R.Br., and Ornithocephalus Hook., with two species each. The remaining eight genera are represented by a single species each in the study area. Morphological descriptions, a key for taxonomic identification, illustrations, and comments on distribution, ecology, phenology and morphology are provided for all inventoried species.


Entre os estudos com Orchidaceae na Amazônia, nenhum compreende a região da Volta Grande do rio Xingu, localizada no baixo Xingu. O objetivo deste estudo foi inventariar e estudar taxonomicamente as espécies de Oncidiinae (Orchidaceae) na Volta Grande do rio Xingu, estado do Pará, Brasil. O levantamento florístico foi realizado na área da Usina Hidrelétrica de Belo Monte, no município de Vitória do Xingu, inserido centralmente na chamada Volta Grande do Xingu. Foram realizadas coletas botânicas entre junho de 2011 e dezembro de 2013. Na área de estudo, foram inventariadas 27 espécies de Oncidiinae, distribuídas em 15 gêneros. Notylia Lindl. e Trichocentrum Poepp. & Endl. foram os mais ricos, com cinco e quatro espécies respectivamente, seguidos por Erycina Lindl., Ionopsis Kunth, Lockhartia Hook., Macradenia R.Br., e Ornithocephalus Hook., com duas espécies cada. Os oito gêneros restantes estão representados na área de estudo por uma única espécie. São fornecidas descrições morfológicas, chave taxonômica para identificação, ilustrações e comentários sobre distribuição, ecologia, fenologia e morfologia para todas as espécies inventariadas.


Subject(s)
Biodiversity , Orchidaceae/classification , Brazil , Plant Dispersal , Ecosystem , Orchidaceae/anatomy & histology , Orchidaceae/physiology
15.
Braz. j. biol ; 75(3,supl.1): 238-249, Aug. 2015. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1468307

ABSTRACT

Microclimatic conditions of tropical forest favour the high richness of bryophytes, which by being sensitive to environmental changes, are important indicators of habitat conditions. The aim of this study was to determine the richness and species composition of the bryophyte flora in fragments of terra firme forest on the great curve of the Xingu River, Pará state, Brazil. The collections were made in August and September 2012 in 14 fragments, in which were installed two plots per fragment, one at the edge and one inside, measuring 10 × 10 m each. The results showed 77 species in 45 genera and 18 families. Lejeunea setiloba Spruce and Marchesinia brachiata (Sw.) Schiffn. are new records for Pará state. The richness families in this study were the ones typically found in tropical forest surveys. A high richness of rare species in comparison to common ones, a pattern usually observed for plants in tropical forests was not reported in this study, probably due to historical fragmentation and disturbance in the area. The richness and species composition were determined mainly by the physiognomic characteristics of the studied forest fragments.


As condições microclimáticas das florestas tropicais favorecem elevada riqueza de briófitas, que por serem sensíveis às alterações ambientais, são importantes indicadoras das condições dos habitats. O objetivo deste trabalho foi determinar a riqueza e a composição florística da brioflora de fragmentos florestais de terra firme na região da Volta Grande do Xingu, Pará, Brasil. As coletas foram realizadas em Agosto e Setembro de 2012, em 14 fragmentos e em cada um destes foram plotadas duas parcelas, uma na borda e outra no interior, medindo 10 × 10 m (cada). Foram registradas 77 espécies, distribuídas em 45 gêneros e 18 famílias. Lejeunea setiloba Spruce e Marchesinia brachiata (Sw.) Schiffn. são novos registros para o Pará. As famílias mais ricas neste estudo foram aquelas tipicamente encontradas em levantamentos em florestas tropicais. A elevada riqueza de espécies raras em comparação às comuns, padrão comumente reportado para plantas em florestas tropicais, não foi observada, provavelmente devido ao histórico de fragmentação e distúrbios na área de estudo. A riqueza e a composição de espécies foram determinadas principalmente pelas características fisionômicas dos fragmentos estudados.


Subject(s)
Biodiversity , Bryophyta/physiology , Forests , Brazil , Plant Dispersal , Ecosystem
16.
Arq. bras. med. vet. zootec ; 67(2): 555-563, Mar-Apr/2015. tab, graf
Article in English | LILACS, VETINDEX | ID: lil-747056

ABSTRACT

The aim of this study was to determine the nutritional requirements of energy and protein for maintenance and weight gain of crossbred cattle, as well as their efficiencies. Fifty 3/4 Zebu × 1/4 Holstein crossbred bulls with initial weights of 214±4kg and aged 11±0.2 months on average were used in this experiment. Four animals were used in the reference group; ten bulls were fed at the maintenance level; and the remaining 36 bulls were fed ad libitum and distributed in a completely randomized design in a 3×3 factorial arrangement, which had three feedlot periods (56, 112 or 168 days) and three calcium and phosphorus levels (low, medium and normal) in the diet. Four of the maintenance animals had their heat production measured by respirometry at the Laboratory of Metabolism and Calorimetry of UFMG. After slaughter, composite samples, referred to as carcass and noncarcass samples were obtained from each animal. The net energy requirements for maintenance (NEm) and metabolizable energy for maintenance (MEm) were 68.9 and 90.1 kcal/EBW0.75/day, respectively. The efficiency (km) was 76.41%. The NEm requirement determined in the respirometry chamber was 85.5 kcal/kg0.75. The following equations were obtained for net energy for gain (NEg) and net protein for gain (NPg): NEg (Mcal/day) = 0.0505±0.000986 × EBW0.75× EBWG1.095 and NPg (g/day) = 162.79±18.2546 × EBWG - 1.30±5.3010 × RE. The efficiencies of fat and protein deposition were 70.04 and 15.12%, respectively. In conclusion, the requirements of NEm for growing and finishing non-castrated 3/4 Zebu × 1/4 Holstein crossbred cattle are 68.9 kcal/EBW0.75/day. Requirements of NEg and NPg can be obtained by the following equations: NEg (Mcal/day) = 0.05050.000986 × EBW0.75 × EBWG1.095 and NPg (g/day) = 162.79±18.2546 × EBWG - 1.30±5.3010× RE.(AU)


Objetivou-se determinar as exigências nutricionais de energia e proteína para mantença e ganho de peso de bovinos cruzados, bem como suas eficiências. Foram utilizados 50 bovinos cruzados 3/4 Zebu × 1/4 Holandês, não castrados, com peso inicial de 214±4kg e idade média de 11±0,2 meses. Quatro animais foram usados para referência, dez para o grupo mantença e os 36 animais alimentados à vontade foram distribuídos em delineamento inteiramente ao acaso em esquema fatorial 3×3, sendo três períodos de confinamento (56, 112 ou 168 dias) e três níveis de cálcio e fósforo (baixo, médio e normal) na dieta. Quatro dos animais mantença foram encaminhados ao laboratório de metabolismo e calorimetria da UFMG para medição da produção de calor através da respirometria. Após os abates, foram obtidas duas amostras compostas para cada animal, denominadas carcaça e não carcaça. As exigências de energia líquida para mantença (ELm) e energia metabolizável para mantença (EMm) foram, respectivamente, de 68,9 e 90,1kcal/PCVZ0,75/dia. A eficiência (km) foi de 76,41%. A exigência de ELm obtida na câmara respirométrica foi de 85,5kcal/kg0,75. As equações obtidas para energia líquida de ganho (ELg) e proteína líquida de ganho (PLg) foram: ELg (Mcal/dia) = 0,0505±0,000986 × PCVZ 0,75 × GPCVZ 1,095 e PLg (g/dia) = 162,79±18,2546 × GPCVZ - 1,30±5,3010 × ER. As eficiências para deposição de gordura e de proteína foram de 70,04 e 15,12%, respectivamente. Conclui-se que as exigências de ELm para bovinos cruzados 3/4 Zebu × 1/4 Holandês não castrados em crescimento e terminação são de 68,9kcal/PCVZ0,75/dia; e que as exigências de ELg e PLg podem ser obtidas pelas respectivas equações: ELg (Mcal/dia) = 0,0505±0,000986 × PCVZ 0,75 × GPCVZ 1,095 e PLg (g/dia) = 162,79±18,2546 × GPCVZ - 1,30±5,3010 × ER.(AU)


Subject(s)
Animals , Cattle , Dietary Minerals/administration & dosage , Calcium, Dietary , Phosphorus, Dietary , Nutritional Requirements , Animal Nutritional Physiological Phenomena
17.
Oper Dent ; 40(4): E158-66, 2015.
Article in English | MEDLINE | ID: mdl-25764042

ABSTRACT

The purpose of this study was to evaluate the influence of direct base and indirect inlay materials on stress distribution and fracture resistance of endodontically treated premolars with weakened cusps. Forty healthy human premolars were selected; five were left intact as controls (group C+), and the others were subjected to endodontic treatment and removal of buccal and lingual cusp dentin. Five teeth were left as negative controls (group C-). The remaining 30 teeth were divided into two groups according to the direct base material (glass ionomer [GIC] or composite resin [CR]). After base placement, each group was subjected to extensive inlay preparation, and then three subgroups were created (n=5): no inlay restoration (GIC and CR), restored with an indirect composite resin inlay (GIC+IR and CR+IR), and restored with a ceramic inlay (GIC+C and CR+C). Each specimen was loaded until fracture in a universal testing machine. For finite element analysis, the results showed that the removal of tooth structure significantly affected fracture resistance. The lowest values were presented by the negative control group, followed by the restored and based groups (not statistically different from each other) and all lower than the positive control group. In finite element analysis, the stress concentration was lower in the restored tooth compared to the tooth without restoration, whereas in the restored teeth, the stress concentration was similar, regardless of the material used for the base or restoration. It can be concluded that the inlay materials combined with a base showed similar behavior and were not able to regain the strength of intact tooth structure.


Subject(s)
Bicuspid , Dental Materials , Dental Stress Analysis , Tooth Fractures/prevention & control , Bicuspid/injuries , Bicuspid/physiology , Dental Cavity Preparation , Dental Restoration, Permanent , Finite Element Analysis , Humans , In Vitro Techniques , Materials Testing , Tensile Strength , Tooth Preparation, Prosthodontic
18.
Oper Dent ; 40(2): 163-71, 2015.
Article in English | MEDLINE | ID: mdl-25136900

ABSTRACT

The aims of this study were to investigate 1) the influence of cleansing methods after saliva contamination and 2) aging conditions (thermocycling and water storage) on zirconia shear bond strength (SBS) with a resin cement. One hundred and eighty zirconia specimens were sandblasted with 50 µm aluminum oxide particles, immersed in saliva for one minute (with the exception of the control group, [C]), and divided into groups according to the cleansing method, as follows: water rinse (W); 37% phosphoric acid gel (PA); cleaning paste (ie, Ivoclean®) containing mainly zirconium oxide (IC); and 70% isopropanol (AL). Scanning electron microscopy was done to qualitatively evaluate the zirconia surface after each cleansing method. For the SBS test, resin cement buttons were bonded to the specimens using a dedicated jig. SBS was evaluated according to standard protocols after 24 hours, 5000 thermal cycles (TC), or 150 days of water storage. Statistical analysis was performed using two-way analysis of variance and Tukey test (p<0.05). Data showed a significant effect for the 150 days of water storage, TC, and 24 hours of water storage (150 days < TC < 24 hours). Group comparisons showed that PA < AL and W < IC and C. SBS ranged from 10.4 to 21.9 MPa (24 hours), from 6.4 to 14.8 MPa (TC), and from 2.9 to 7.0 MPa (150 days). Failure analysis revealed a greater percentage of mixed failures for the majority of the specimens and a smaller percentage of adhesive failures at the ceramic-resin cement interface. Our findings suggest that Ivoclean® was able to maintain adequate SBS values after TC and 150 days of storage, comparable to the uncontaminated zirconia.


Subject(s)
Resin Cements/metabolism , Saliva/metabolism , Yttrium/metabolism , Zirconium/metabolism , Dental Bonding , Dental Stress Analysis , Humans , Microscopy, Electron, Scanning , Photoelectron Spectroscopy
19.
Arq. bras. med. vet. zootec ; 66(6): 1822-1830, 12/2014. tab
Article in Portuguese | LILACS | ID: lil-735760

ABSTRACT

Foram utilizadas três vacas não lactantes fistuladas no rúmen com o objetivo de determinar os parâmetros de degradação ruminal in situ da matéria seca (MS) e do amido de grãos de sorgo sob diferentes formas de processamento: 1) Seco e moído (2mm); 2) Seco, moído (3mm), reidratado com aspersão de água sobre o material, e imediatamente ensilado por 30 dias; 3) Seco, inteiro, reidratado por três dias em tubo PVC e, em seguida, moído a 5mm; 4) Seco, inteiro, reidratado por três dias em tubo PVC com aplicação de ar comprimido e, em seguida, moído a 5mm; 5) Seco, inteiro, reidratado por três dias em tubo PVC e, em seguida, moído a 5mm, e ensilado por 30 dias; 6) Seco, inteiro, reidratado por três dias em tubo PVC com aplicação de ar comprimido, moído a 5mm e ensilado por 30 dias. Os teores de proteína bruta, amido, e fibra em detergente neutro (% da MS) variaram de 9,8 a 10,8%; 59,5 a 67,5%; e de 16,1 a 19,3%, respectivamente. Os teores de umidade nos grãos que foram reidratados variaram de 35,8 a 43,9% da MS. A taxa e a extensão de degradação do amido e a degradabilidade potencial da MS foram semelhantes (P>0,05) entre tratamentos. Os grãos de sorgo reidratados com aplicação de ar comprimido, moídos e ensilados (tratamento 6) apresentaram degradabilidade efetiva (DE) da MS e DE do amido sob taxa de passagem ruminal de 2%/h, semelhantes (P>0,05) às observadas para o tratamento 5 (sem aplicação de ar comprimido), e superiores (P<0,05) às dos demais processamentos. Sob taxas de passagem no rúmen de 5 e 8%/h, as DE do amido estimadas para os grãos processados no tratamento 6 foram superiores (P<0,05) às obtidas para os demais tratamentos. O processamento de reidratação por três dias com aplicação de ar comprimido e ensilagem por trinta dias aumentou a degradabilidade efetiva da matéria seca e do amido dos grãos de sorgo, e sua utilização pode ser recomendada para animais em níveis intermediário e elevado de desempenho...


Used three non-lactating cows fistulated in the rumen in order to determine the parameters of in situ ruminal degradation of dry matter (DM) and starch grain sorghum under different forms of processing: 1) Dried and ground (2mm); 2) Dry, crushed (3mm), rehydrated with water spray on the material and immediately ensiled for 30 days, 3) Dry, round, rehydrated for three days in PVC pipe and then crushed to 5mm, 4 ) Dry, full-rehydrated for three days in PVC tube with application of compressed air and then ground to 5mm; 5) Dry, full-rehydrated for three days in PVC pipe and then ground to 5mm, and ensiled for 30 days; 6) Dry, full-rehydrated for three days in PVC tube with application of compressed air, ground to 5mm and ensiled for 30 days. The crude protein, starch, and neutral detergent fiber (% of DM) ranged from 9.8 to 10.8%, 59.5 to 67.5%, and 16.1 to 19.3%, respectively. The moisture in the grains that were rehydrated ranged from 35.8 to 43.9% DM. The rate and extent of starch degradation and the degradability of MS were similar (P>0.05) between treatments. The grain sorghum rehydrated with application of compressed air, ground and ensiled (treatment 6), showed effective degradability (ED) of DM, and DE starch under ruminal passage rate of 2%/h, similar (P>0.05 ) those observed for treating 5 (without application of compressed air) and higher (P<0.05) to the other processing. Under rumen passage rates of 5 and 8%/h, the estimated NDs starch for processed grains in treatment 6 were higher (P<0.05) than those obtained for the other treatments. Processing rehydration for three days with compressed air application and silage for thirty days increased the effective degradability of dry matter and starch grain sorghum, and its use can be recommended for animals in intermediate and high performance...


Subject(s)
Animals , Cattle , Cattle , Fluid Therapy/veterinary , Rumen/abnormalities , Sorghum , Starch/administration & dosage , Silage/analysis , Silage/adverse effects
20.
Oper Dent ; 39(2): 144-51, 2014.
Article in English | MEDLINE | ID: mdl-23786611

ABSTRACT

OBJECTIVE: This study evaluated the effect of quantity of resin composite, C-factor, and geometry in Class V restorations on shrinkage stress after bulk fill insertion of resin using two-dimensional finite element analysis. METHODS: An image of a buccolingual longitudinal plane in the middle of an upper first premolar and supporting tissues was used for modeling 10 groups: cylindrical cavity, erosion, and abfraction lesions with the same C-factor (1.57), a second cylindrical cavity and abfraction lesion with the same quantity of resin (QR) as the erosion lesion, and then all repeated with a bevel on the occlusal cavosurface angle. The 10 groups were imported into Ansys 13.0 for two-dimensional finite element analysis. The mesh was built with 30,000 triangle and square elements of 0.1 mm in length for all the models. All materials were considered isotropic, homogeneous, elastic, and linear, and the resin composite shrinkage was simulated by thermal analogy. The maximum principal (MPS) and von Mises stresses (VMS) were analyzed for comparing the behavior of the groups. RESULTS: Different values of angles for the cavosurface margin in enamel and dentin were obtained for all groups and the higher the angle, the lower the stress concentration. When the groups with the same C-factor and QR were compared, the erosion shape cavity showed the highest MPS and VMS values, and abfraction shape, the lowest. A cavosurface bevel decreased the stress values on the occlusal margin. The geometry factor overcame the effects of C-factor and QR in some situations. CONCLUSION: Within the limitations of the current methodology, it is possible to conclude that the combination of all variables studied influences the stress, but the geometry is the most important factor to be considered by the operator.


Subject(s)
Composite Resins/therapeutic use , Dental Caries/pathology , Dental Restoration, Permanent/methods , Bicuspid/pathology , Dental Cavity Preparation/methods , Dental Restoration Failure , Dental Stress Analysis , Humans
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