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1.
J Anim Sci Technol ; 66(1): 145-155, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38618035

RESUMO

This study was conducted to determine the effects of amino acid (AA) supplementation in low-protein (LP) diets on growth performance and nitrogen (N) excretion. A total of 175 7-day-old Ross 308 male broilers, with a mean body weight (BW) of 165 g (standard deviation = 11.2 g), were grouped into five blocks by BW and allocated to seven treatments according to a randomized complete block design with five replicate cages at five birds per cage. Dietary treatments comprised a control diet containing 20.0% crude protein (CP) and six LP diets containing either 18.5% or 17.0% CP. These LP diets were supplemented with either no AA supplementation, indispensable AA, or both indispensable and dispensable AA (glutamic acid and glycine). Birds were fed experimental grower diets from day 7 to 21 and then commercial finisher diets until day 28. During the grower period (day 7 to 21), birds fed LP diets supplemented with indispensable AA exhibited greater (p < 0.05) BW, body weight gain (BWG), feed intake (FI), and gain-to-feed ratio (G:F) than birds fed LP diets without crystalline AA and were comparable to birds fed the control diet. During the finisher period (day 21 to 28), birds fed LP diets supplemented with indispensable AA showed greater (p < 0.05) BW than birds fed LP diets without crystalline AA, and their growth performance was comparable to birds fed the control diet. Throughout the overall period, supplementing indispensable AA in LP diets resulted in elevated (p < 0.05) BWG, FI, and G:F more than those of LP diets without crystalline AA and were comparable to those of the control diet. Supplementing indispensable AA in LP diets decreased amount and coefficient of N excretion as much as the control diet. Dispensable AA supplementation in LP diets did not influence growth performance and N excretion. In conclusion, supplementing indispensable AA in LP diets maintains growth performance and N excretion until the dietary CP lowers from 20.0% to 17.0% during the grower period. As long as dietary CP is above 17.0%, dispensable AA may not be deficient in LP diets during the grower period.

2.
Nanomaterials (Basel) ; 13(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37299644

RESUMO

Two-dimensional (2D) MXenes sheet-like micro-structures have attracted attention as an effective electrochemical energy storage material due to their efficient electrolyte/cation interfacial charge transports inside the 2D sheets which results in ultrahigh rate capability and high volumetric capacitance. In this article, Ti3C2Tx MXene is prepared by a combination of ball milling and chemical etching from Ti3AlC2 powder. The effects of ball milling and etching duration on the physiochemical properties are also explored, as well as the electrochemical performance of as-prepared Ti3C2 MXene. The electrochemical performances of 6 h mechanochemically treated and 12 h chemically etched MXene (BM-12H) exhibit an electric double layer capacitance behavior with an enhanced specific capacitance of 146.3 F g-1 compared to 24 and 48 h treated samples. Moreover, 5000-cycle stability tested sample's (BM-12H) charge/discharge show increased specific capacitance due to the termination of the -OH group, intercalation of K+ ion and transformation to TiO2/Ti3C2 hybrid structure in a 3 M KOH electrolyte. Interestingly, a symmetric supercapacitor (SSC) device fabricated in a 1 M LiPF6 electrolyte in order to extend the voltage window up to 3 V shows a pseudocapacitance behavior due to Li on interaction/de-intercalation. In addition, the SSC shows an excellent energy and power density of 138.33 W h kg-1 and 1500 W kg-1, respectively. The ball milling pre-treated MXene exhibited an excellent performance and stability due to the increased interlayer distance between the MXene sheets and intercalation and deintercalation of Li+ ions.

3.
Molecules ; 27(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36431792

RESUMO

In this manuscript, we are reporting for the first time one dimensional (1D) cerium hydrogen phosphate (Ce(HPO4)2.xH2O) electrode material for supercapacitor application. In short, a simple hydrothermal technique was employed to prepare Ce(HPO4)2.xH2O. The maximum surface area of 82 m2 g-1 was obtained from nitrogen sorption isotherm. SEM images revealed Ce(HPO4)2.xH2O exhibited a nanorod-like structure along with particles and clusters. The maximum specific capacitance of 114 F g-1 was achieved at 0.2 A g-1 current density for Ce(HPO4)/NF electrode material in a three-electrode configuration. Furthermore, the fabricated symmetric supercapacitor (SSC) based on Ce(HPO4)2.xH2O//Ce(HPO4)2.xH2O demonstrates reasonable specific energy (2.08 Wh kg-1), moderate specific power (499.88 W kg-1), and outstanding cyclic durability (retains 92.7% of its initial specific capacitance after 5000 GCD cycles).


Assuntos
Cério , Hidrogênio , Eletrodos , Capacitância Elétrica , Fosfatos
4.
J Food Sci ; 87(6): 2757-2765, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35534091

RESUMO

The current study investigated that the vitamin C absorption in plasma depends on the individual muscle mass and the formulation including drinks (Vita 500), capsules, and tablets by using a randomized and double-blind clinical study. The volunteers were divided into two groups that depended on their muscle mass, including those whose muscle mass was greater than 40% ( ≥ $ \ge $ 40%) and less than 40% muscle mass (<40%). Levels of vitamin C in blood plasma was analyzed by high-performance liquid chromatography by ultraviolet detection (HPLC-UV). The existing HPLC method was modified according to lab conditions but maintained a constantly low pH sample reduction procedure. The analytical method validated stability, linearity, recovery, reliability, and accuracy. The vitamin C absorption was the highest at 120 min after ingesting Vita 500 (21.47 ± 15.99 µmol/L). It was higher in the group that has more than 40% muscle mass compared to other formulations, such as tablets and capsules. The results from the current study indicate that vitamin C formulations differently affect the vitamin C absorption, and its effect depends on the muscle mass. As the results, liquid type vitamin C formulations could enhance vitamin C absorption, which resulted in an improvement of vitamin C absorption according to muscle mass. PRACTICAL APPLICATION: The results of this study may recommend using vitamin C supplementation as liquid type. It may also provide evidence that people with higher muscle mass can absorb vitamin C more efficiently.


Assuntos
Ácido Ascórbico , Vitaminas , Cápsulas , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Humanos , Músculos , Projetos Piloto , Reprodutibilidade dos Testes , Comprimidos
5.
Dalton Trans ; 49(41): 14432-14444, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33044469

RESUMO

The integration of metal oxide composite nanostructures has attracted great attention in supercapacitor (SC) applications. Herein, we fabricated a series of metal oxide composite nanostructures, including ZnO nanowires, NiO nanosheets, ZnO/CuO nanowire arrays, ZnO/FeO nanocrystals, ZnO/NiO nanosheets and ZnO/PbO nanotubes, via a simple and cost-effective chemical bath deposition (CBD) method. The electrochemical properties of the produced SCs were examined by performing cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) analysis, and electrochemical impedance spectroscopy (EIS). Of the different metal oxides and metal oxide composites tested, the unique surface morphology of the ZnO/NiO nanosheets most effectively increased the electron transfer rate and electrical conductivity, which resulted in improved energy storage properties. The binder-free ZnO/NiO electrode delivered a high specific capacitance/capacity of 1248 F g-1 (599 mA h g-1) at 8 mA cm-2 and long-term cycling stability over the course of 3000 cycles with a capacity retention of 79%. These results suggested a superiority in performance of the ZnO/NiO nanosheets relative to the nanowires, nanowire arrays, nanocrystals, and nanotubes. Thus, the present work has provided an opportunity to fabricate new metal oxide composite nanostructures with high-performance energy storage devices.

6.
Dalton Trans ; 48(23): 8254-8263, 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31095147

RESUMO

Herein, we report a simple and cost-effective route for the fabrication of NiWO4, NiWO4P, and NiWO4Se nanostructures using the chemical bath deposition method. As a binder-free electrode material for pseudo capacitors (PCs), the fabricated nickel foam-supported NiWO4Se exhibited an excellent cycling life of 3000 cycles with a high specific capacitance of 1115.05 F g-1 at 20 mA cm-2. The desirable electrochemical performance of NiWO4Se was mainly attributed to the large specific area, short ion diffusion distance, and the introduction of selenium, which provide transport pathways for electrons and provide more active sites for electrochemical energy storage. The present simple and scalable synthesis shows great potential for the future development of transition metal selenides for different energy storage and conversion applications.

7.
RSC Adv ; 9(37): 21225-21232, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35521331

RESUMO

NF/ZnOx nanocone and NF/CoOx nanoparticle electrode materials were fabricated on a nickel foam surface using a simple chemical bath deposition approach and assessed as an electrode material for high-performance supercapacitors (SCs). The electrochemical properties of the NF/ZnOx and NF/CoOx electrodes were examined by cyclic voltammetry, galvanostatic charge-discharge tests, and electrochemical impedance spectroscopy. The fabricated NF/ZnOx and NF/CoOx SCs devices exhibited a good specific capacitance of 2437 and 2142 F g-1 at a current density of 20 mA g-1, respectively, in a three electrode system. Furthermore, the NF/ZnOx and NF/CoOx electrode materials showed acceptable long cycle-life stability with 97.8% and 95.8% specific capacitance retention after 3000 cycles at a current density of 22 mA g-1 in a 2 M aqueous KOH solution. Furthermore, the NF/ZnOx and NF/CoOx SCs showed a high energy density of 54.15 W h kg-1 and 47.6 W h kg-1 at a power density of 499.8 W kg-1 and 571.2 W kg-1, respectively, with maximum operating voltage of 0.5 V. Overall, NF/ZnOx and NF/CoOx electrode materials are promising electrodes for electrochemical energy storage applications.

8.
J Exerc Nutrition Biochem ; 22(4): 39-54, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30661330

RESUMO

PURPOSE: This study aimed to study the protective effects and mechanism of Blue Honeysuckle (BH) extracts (Berries of Lonicera caerulea L.) on non-alcoholic fatty liver disease (NAFLD) and obesity risk factors in a high fat-diet (HFD) model. METHODS: Animals adapted to HFD were selected after 1 week of adaption period and divided into 6 groups (8 mice in each group; 40 HFD-fed mice and 8 normal fat pellet diet (NFD)-fed mice). After the end of 12 weeks of continuous oral administrations of 3 different dosages of BH extract, 400, 200 and 100 mg/kg, or metformin 250 mg/kg, dissolved in a volume of 10 mL/kg distilled water, the hepatoprotective, hypolipidemic, hypoglycemic, nephroprotective, and anti-obesity effects were analyzed. RESULTS: The BH extract improved fat density and mass, adipocyte histopathology, hepatocyte hypertrophy, hepatic enzyme activity, lipid metabolism, and related gene expression including ACC1, AMPK α1 and AMPK α2 in hepatic tissue, leptin, UCP2, adiponectin, C/EBP α, C/EBPß and SREBP1c in adipose tissue. Especially, 200 mg/kg of BH extract constantly improved NAFLD and obesity risk factors through AMPK upregulation-mediated hepatic glucose enzyme activity, lipid metabolism-related gene expression, and activation of the antioxidant defense system, to a level comparable to that of metformin 250 mg/kg in HFD-fed mice. CONCLUSION: BH extract has the potential to reduce the risk factors associated with obesity, in addition to the remarkable effect of preventing NAFLD. Future research will need to be done to determine whether these results are consistent in human studies.

9.
J Adv Prosthodont ; 8(1): 9-15, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26949482

RESUMO

PURPOSE: Although magnetic attachment is used frequently for overdenture, it is reported that attractive force can be decreased by abrasion and corrosion. The purpose of this study was to establish the clinical basis about considerations and long term prognosis of overdenture using magnetic attachments by investigating the change in attractive force of magnetic attachment applied to the patients. MATERIALS AND METHODS: Among the patients treated with overdenture using magnetic attachments in Dankook University Dental Hospital, attractive force records of 61 magnetic attachments of 20 subjects who re-visited from July 2013 to June 2014 were analyzed. Dental magnet tester (Aichi Micro Intelligent Co., Aichi, Japan) was used for measurement. The magnetic attachments used in this study were Magfit IP-B Flat, Magfit DX400, Magfit DX600 and Magfit DX800 (Aichi Steel Co., Aichi, Japan) filled with Neodymium (NdFeB), a rare-earth magnet. RESULTS: Reduction ratio of attractive force had no significant correlation with conditional variables to which attachments were applied, and was higher when the maintenance period was longer (P<.05, r=.361). Reduction ratio of attractive force was significantly higher in the subject group in which attachments were used over 9 years than within 9 years (P<.05). Furthermore, 16.39% of total magnetic attachments showed detachment of keeper or assembly. CONCLUSION: Attractive force of magnetic attachment is maintained regardless of conditional variables and reduction ratio increased as the maintenance period became longer. Further study on adhesive material, attachment method and design improvement to prevent detachment of magnetic attachment is needed.

11.
Sci Rep ; 5: 10768, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26066664

RESUMO

Microscale soft-robots hold great promise as safe handlers of delicate micro-objects but their wider adoption requires micro-actuators with greater efficiency and ease-of-fabrication. Here we present an elastomeric microtube-based pneumatic actuator that can be extended into a microrobotic tentacle. We establish a new, direct peeling-based technique for building long and thin, highly deformable microtubes and a semi-analytical model for their shape-engineering. Using them in combination, we amplify the microtube's pneumatically-driven bending into multi-turn inward spiraling. The resulting micro-tentacle exhibit spiraling with the final radius as small as ~185 µm and grabbing force of ~0.78 mN, rendering itself ideal for non-damaging manipulation of soft, fragile micro-objects. This spiraling tentacle-based grabbing modality, the direct peeling-enabled elastomeric microtube fabrication technique, and the concept of microtube shape-engineering are all unprecedented and will enrich the field of soft-robotics.

12.
J Adv Prosthodont ; 6(4): 285-94, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25177472

RESUMO

PURPOSE: The purpose of this study was to evaluate the properties of a porous zirconia scaffold coated with bioactive materials and compare the in vitro cellular behavior of MC3T3-E1 preosteoblastic cells to titanium and zirconia disks and porous zirconia scaffolds. MATERIALS AND METHODS: Titanium and zirconia disks were prepared. A porous zirconia scaffold was fabricated with an open cell polyurethane disk foam template. The porous zirconia scaffolds were coated with ß-TCP, HA and a compound of ß-TCP and HA (BCP). The characteristics of the specimens were evaluated using scanning electron microscopy (SEM), energy dispersive x-ray spectrometer (EDX), and x-ray diffractometry (XRD). The dissolution tests were analyzed by an inductively coupled plasma spectrometer (ICP). The osteogenic effect of MC3T3-E1 cells was assessed via cell counting and reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: The EDX profiles showed the substrate of zirconia, which was surrounded by the Ca-P layer. In the dissolution test, dissolved Ca(2+) ions were observed in the following decreasing order; ß-TCP > BCP > HA (P<.05). In the cellular experiments, the cell proliferation on titanium disks appeared significantly lower in comparison to the other groups after 5 days (P<.05). The zirconia scaffolds had greater values than the zirconia disks (P<.05). The mRNA level of osteocalcin was highest on the non-coated zirconia scaffolds after 7 days. CONCLUSION: Zirconia had greater osteoblast cell activity than titanium. The interconnecting pores of the zirconia scaffolds showed enhanced proliferation and cell differentiation. The activity of osteoblast was more affected by microstructure than by coating materials.

13.
J Adv Prosthodont ; 6(1): 53-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24605207

RESUMO

PURPOSE: The aim of this study was to obtain statistical data on the residual bone height at different natural tooth positions by panoramic radiography in edentulous Korean patients aged 60-90 years. MATERIALS AND METHODS: The study included the diagnostic panoramic radiographs of 180 randomly selected edentulous patients without systemic diseases affecting bone. The radiographic selection criteria included absence of obvious facial asymmetry, clearly visible anatomic structures, and no surgical and fracture history. The panoramic radiographs of 79 patients met these criteria and were used in the analysis. The same researcher processed all the radiographs by using a standardized method. The height of the residual bone was measured at 18 predetermined sites (7 in the maxilla and 11 in the mandible) on digitized and printed radiographs by using a Digimatic caliper, triangle, and ruler. Gender- and age-related differences were statistically analyzed by using the t-test and rank-sum test (α=0.05). RESULTS: The maxillary residual bone height did not show significant gender-related differences, but male patients had significantly higher residual bone in the mandible(P<.05). No significant height differences at the measured sites were noted among the 60s, 70s, and 80s age groups. CONCLUSION: Dentists should pay greater attention to older female edentulous patients because they are more prone to rapid residual bone resorption. Residual bone resorption may not be affected by age.

14.
Apoptosis ; 18(11): 1332-1347, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23907580

RESUMO

Alzheimer's disease (AD) is characterized by the deposition of aggregated amyloid-beta (Aß), which triggers a cellular stress response called the unfolded protein response (UPR). The UPR signaling pathway is a cellular defense system for dealing with the accumulation of misfolded proteins but switches to apoptosis when endoplasmic reticulum (ER) stress is prolonged. ER stress is involved in neurodegenerative diseases including AD, but the molecular mechanisms of neuronal apoptosis and inflammation by Aß-induced ER stress to exercise training are not fully understood. Here, we demonstrated that treadmill exercise (TE) prevented PS2 mutation-induced memory impairment and reduced Aß-42 deposition through the inhibition of ß-secretase (BACE-1) and its product, C-99 in cortex and/or hippocampus of aged PS2 mutant mice. We also found that TE down-regulated the expression of GRP78/Bip and PDI proteins and inhibited activation of PERK, eIF2α, ATF6α, sXBP1 and JNK-p38 MAPK as well as activation of CHOP, caspase-12 and caspase-3. Moreover, TE up-regulated the expression of Bcl-2 and down-regulated the expressions of Bax in the hippocampus of aged PS2 mutant mice. Finally, the generation of TNFα and IL-1α and the number of TUNEL-positive cells in the hippocampus of aged PS2 mutant mice was also prevented or decreased by TE. These results showed that TE suppressed the activation of UPR signaling pathways as well as inhibited the apoptotic pathways of the UPR and inflammatory response following Aß-induced ER stress. Thus, therapeutic strategies that modulate Aß-induced ER stress through TE could represent a promising approach for the prevention or treatment of AD.


Assuntos
Envelhecimento/genética , Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/genética , Estresse do Retículo Endoplasmático/genética , Fragmentos de Peptídeos/genética , Condicionamento Físico Animal , Presenilina-2/genética , Envelhecimento/metabolismo , Envelhecimento/patologia , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/metabolismo , Caspases/genética , Caspases/metabolismo , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Chaperona BiP do Retículo Endoplasmático , Regulação da Expressão Gênica , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Inflamação/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Fragmentos de Peptídeos/metabolismo , Presenilina-2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Resposta a Proteínas não Dobradas/genética
15.
J Adv Prosthodont ; 5(2): 172-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23755344

RESUMO

PURPOSE: The purpose of this study was to assess the difference in efficacy between calcium metaphosphate (CMP)-coated implant fixtures and conventional resorbable blasted media (RBM) processed implant fixtures. MATERIALS AND METHODS: This study targeted 50 implants from 44 patients who visited Dankook University Dental Hospital. Implantations were done separately for RBM treated and CMP-coated implants, although their design was the same. Calcium metaphosphate has a quicker biodegradation process through hydrolysis compared to other phosphate calcium groups. For the first year of the implantation, the resorption volume of marginal bone analyzed via radiography and perio-test value were measured, under the check plan. Their analyses were composed of a non-inferiority trials test. A 95% level of reliability was used. RESULTS: In the comparative analysis of the resorption volume of marginal bone and the perio-test value, no statistically significant difference was found between the CMP-coated implants and RBM implants. CONCLUSION: One year after the implant placement, CMP-coated implants were found not to be inferior to the conventional RBM implants.

16.
Int J Oral Maxillofac Implants ; 27(2): 295-302, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22442767

RESUMO

PURPOSE: The purpose of the present study was to investigate the stress distribution around the bone-implant interface and the effect of the length of an immediately loaded implant in the anterior maxilla using a finite element model with simulated loading stresses. MATERIALS AND METHODS: Four-mm-diameter external-hex implants with different lengths (8.5, 10.0, 11.5, 13.0, and 15.0 mm) were used in this study. The anterior maxilla was assumed to be D3 bone quality. All of the material was assumed to be homogenous, isotropic, and linearly elastic. Average bone deformation during implant placement was calculated through the simulation process, and using this, insertion stress was created. The bone-implant interface was constructed using a contact element to simulate a nonosseointegrated condition. Then, 176 N of static force was applied at the middle of the palatoincisal line angle of the abutment at a 120-degree angle to the long axis of the abutment. The von Mises stresses were measured at intervals of 0.25 mm along the bone-implant interface. RESULTS: Prior to loading, the stresses were evenly distributed around the implant and highly concentrated in the cortical area. When the load was applied, von Mises stresses were concentrated in the cortical bone of the implant neck area. More favorable stress distribution was seen with increasing implant length. However, when the implant length reached 15.0 mm, the stresses increased. CONCLUSIONS: In the maxilla, when immediate loading is applied after implant placement, 11.5- and 13.0-mm-long single implants showed more favorable stress patterns than the others analyzed. If implants longer than 15.0 mm are used in immediate loading, sufficient bone volume in the recipient site should be considered an important factor.


Assuntos
Implantes Dentários para Um Único Dente , Análise de Elementos Finitos , Imageamento Tridimensional/métodos , Carga Imediata em Implante Dentário , Maxila/anatomia & histologia , Força de Mordida , Densidade Óssea/fisiologia , Simulação por Computador , Dente Suporte , Planejamento de Prótese Dentária , Humanos , Teste de Materiais , Maxila/cirurgia , Modelos Biológicos , Estresse Mecânico , Propriedades de Superfície
17.
Anal Chem ; 83(22): 8596-603, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-22017332

RESUMO

Hardware from a commercial-off-the-shelf (COTS) ion mobility spectrometry (IMS) based explosive trace detector (ETD) has been interfaced to an AB/SCIEX API 2000 triple quadrupole mass spectrometer. To interface the COTS IMS based ETD to the API 2000, the faraday plate of the IMS instrument and the curtain plate of the mass spectrometer were removed from their respective systems and replaced by a custom faraday plate, which was fabricated with a hole for passing the ion beam to the mass spectrometer, and a custom interface flange, which was designed to attach the IMS instrument onto the mass spectrometer. Additionally, the mass spectrometer was modified to increase the electric field strength and decrease the pressure in the differentially pumped interface, causing a decrease in the effect of collisional focusing and permitting a mobility spectrum to be measured using the mass spectrometer. The utility of the COTS-ETD/API 2000 configuration for the characterization of the gas phase ion chemistry of COTS-ETD equipment was established by obtaining mass and tandem mass spectra in the continuous ion flow and selected mobility monitoring operating modes and by obtaining mass-selected ion mobility spectra for the explosive standard 2,4,6 trinitrotoluene (TNT). This analysis confirmed that the product ion for TNT is [TNT - H](-), the predominant collision-induced dissociation pathway for [TNT- H](-) is the loss of NO and NO(2), and the reduced mobility value for [TNT - H](-) is 1.54 cm(2)V(-1) s(-1). Moreover, this analysis was attained for sample amounts of 1 ng and with a resolving power of 37. The objective of the research is to advance the operational effectiveness of COTS IMS based ETD equipment by developing a platform that can facilitate the understanding of the ion chemistry intrinsic to the equipment.


Assuntos
Trinitrotolueno/análise , Espectrometria de Massas/instrumentação
18.
Neurosci Res ; 69(2): 161-73, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20969897

RESUMO

The present study was undertaken to further investigate the protective effect of treadmill exercise on the hippocampal proteins associated with neuronal cell death in an aged transgenic (Tg) mice with Alzheimer's disease (AD). To address this, Tg mouse model of AD, Tg-NSE/PS2m, which expresses human mutant PS2 in the brain, was chosen. Animals were subjected to treadmill exercise for 12 weeks from 24 months of age. The exercised mice were treadmill run at speed of 12 m/min, 60 min/day, 5 days/week on a 0% gradient for 3 months. Treadmill exercised mice improved cognitive function in water maze test. Treadmill exercised mice significantly reduced the expression of Aß-42, Cox-2, and caspase-3 in the hippocampus. In parallel, treadmill exercised Tg mice decreased the phosphorylation levels of JNK, p38MAPK and tau (Ser404, Ser202, Thr231), and increased the phosphorylation levels of ERK, PI3K, Akt and GSK-3α/ß. In addition, treadmill exercised Tg mice up-regulated the expressions of NGF, BDNF and phospho-CREB, and the expressions of SOD-1, SOD-2 and HSP-70. Treadmill exercised Tg mice up-regulated the expression of Bcl-2, and down-regulated the expressions of cytochrome c and Bax in the hippocampus. The number of TUNEL-positive cells in the hippocampus in mice was significantly decreased after treadmill exercise. Finally, serum TC, insulin, glucose, and corticosterone levels were significantly decreased in the Tg mice after treadmill exercise. As a consequence of such change, Aß-dependent neuronal cell death in the hippocampus of Tg mice was markedly suppressed following treadmill exercise. These results strongly suggest that treadmill exercise provides a therapeutic potential to inhibit both Aß-42 and neuronal death pathways. Therefore, treadmill exercise may be beneficial in prevention or treatment of AD.


Assuntos
Doença de Alzheimer/prevenção & controle , Apoptose/fisiologia , Expressão Gênica/fisiologia , Neurônios/patologia , Condicionamento Físico Animal/fisiologia , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Animais , Western Blotting , Modelos Animais de Doenças , Hipocampo/patologia , Hipocampo/fisiopatologia , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Transgênicos , Transdução de Sinais/fisiologia
19.
J Adv Prosthodont ; 2(2): 39-45, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21165186

RESUMO

PURPOSE: The aim of this study was to determine differences in shear bond strength to human dentin using immediate dentin sealing (IDS) technique compared to delayed dentin sealing (DDS). MATERIALS AND METHODS: Forty extracted human molars were divided into 4 groups with 10 teeth each. The control group was light-cured after application of dentin bonding agent (Excite® DSC) and cemented with Variolink® II resin cement. IDS/SE (immediate dentin sealing, Clearfil™ SE Bond) and IDS/SB (immediate dentin sealing, AdapterTM Single Bond 2) were light-cured after application of dentin bonding agent (Clearfil™ SE Bond and Adapter™ Sing Bond 2, respectively), whereas DDS specimens were not treated with any dentin bonding agent. Specimens were cemented with Variolink® II resin cement. Dentin bonding agent (Excite® DSC) was left unpolymerized until the application of porcelain restoration. Shear strength was measured using a universal testing machine at a speed of 5 mm/min and evaluated of fracture using an optical microscope. RESULTS: The mean shear bond strengths of control group and IDS/SE group were not statistically different from another at 14.86 and 11.18 MPa. Bond strength of IDS/SE group had a significantly higher mean than DDS group (3.14 MPa) (P < .05). There were no significance in the mean shear bond strength between IDS/SB (4.11 MPa) and DDS group. Evaluation of failure patterns indicates that most failures in the control group and IDS/SE groups were mixed, whereas failures in the DDS were interfacial. CONCLUSION: When preparing teeth for indirect ceramic restoration, IDS with Clearfil™ SE Bond results in improved shear bond strength compared with DDS.

20.
J Forensic Sci ; 55(2): 334-40, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20102455

RESUMO

A method is described to perform automated mapping of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) particles in C-4 fingerprints. The method employs polarized light microscopy and image analysis to map the entire fingerprint and the distribution of RDX particles. This method can be used to evaluate a large number of fingerprints to aid in the development of threat libraries that can be used to determine performance requirements of explosive trace detectors. A series of 50 C-4 fingerprints were characterized, and results show that the number of particles varies significantly from print to print, and within a print. The particle size distributions can be used to estimate the mass of RDX in the fingerprint. These estimates were found to be within +/-26% relative of the results obtained from dissolution gas chromatography/micro-electron capture detection for four of six prints, which is quite encouraging for a particle counting approach. By evaluating the average mass and frequency of particles with respect to size for this series of fingerprints, we conclude that particles 10-20 microm in diameter could be targeted to improve detection of traces of C-4 explosives.

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