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1.
J Prosthet Dent ; 125(1): 73-81, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32057487

RESUMO

STATEMENT OF PROBLEM: Limited information is available regarding the fabrication of tooth-supported interim single crowns (SCs) with either a digital or a conventional workflow. PURPOSE: The purpose of this randomized clinical trial was to compare the time efficiency and fit of interim crowns fabricated by using either a digital or a conventional workflow. MATERIAL AND METHODS: Forty participants in need of posterior tooth-supported SCs were enrolled and randomly allocated to either the digital or conventional group. In the digital group, the interim SCs were fabricated by using digital sextant scans and computer-aided design and computer-aided manufacturing (CAD-CAM) technology without definitive casts. The conventional group included conventional impressions and direct fabrication of the interim restorations intraorally. Five experienced and 5 less experienced clinicians were randomly assigned to fabricate the interim SCs. The total fabrication time (laboratory and clinical) was recorded for time efficiency. The fit assessment included marginal fit, proximal contact, occlusal contact, and crown morphology. The evaluated parameters were analyzed with the Mann-Whitney U Test (α=.05). RESULTS: The digital workflow required significantly less total fabrication time (laboratory and clinical) than the conventional workflow (P<.001). The less-experienced clinicians needed longer clinical time with the conventional workflow than the experienced ones (P=.023). In contrast, the laboratory time and total fabrication time were shorter for less-experienced clinicians using the digital workflow (P=.005 and P=.015). The interim SCs fabricated with the digital workflow had significantly better fit and occlusal contacts than those fabricated with the conventional workflow (P=.005 and P<.001). With the digital workflow, the interim SCs made by less-experienced clinicians were of the same quality as those made by experienced clinicians. When using the conventional workflow, the fit of the experienced clinicians was significantly better than that of the less-experienced clinicians. CONCLUSIONS: The interim SCs fabricated with a digital workflow required a shorter fabrication time and resulted in better fit than those fabricated with a conventional workflow, especially for less-experienced clinicians.


Assuntos
Técnica de Moldagem Odontológica , Planejamento de Prótese Dentária , Cerâmica , Desenho Assistido por Computador , Coroas , Adaptação Marginal Dentária , Porcelana Dentária , Humanos , Fluxo de Trabalho
2.
Am J Orthod Dentofacial Orthop ; 159(5): 582-593, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33771430

RESUMO

INTRODUCTION: Orthodontic tooth movement (OTM) relies on efficient remodeling of alveolar bone. While a well-controlled inflammatory response is essential during OTM, the mechanism regulating inflammation is unknown. Autophagy, a conserved catabolic pathway, has been shown to protect cells from excess inflammation in disease states. We hypothesize that autophagy plays a role in regulating inflammation during OTM. METHODS: A split-mouth design was used to force load molars in adult male mice, carrying a GFP-LC3 transgene for in vivo detection of autophagy. Confocal microscopy, Western blot, and quantitative polymerase chain reaction analyses were used to evaluate autophagy activation in tissues of loaded and control molars at time points after force application. Rapamycin, a Food and Drug Administration-approved immunosuppressant, was injected to evaluate induction of autophagy. RESULTS: Autophagy activity increases shortly after loading, primarily on the compression side of the tooth, and is closely associated with inflammatory cytokine expression and osteoclast recruitment. Daily administration of rapamycin, an autophagy activator, led to reduced tooth movement and osteoclast recruitment, suggesting that autophagy downregulates the inflammatory response and bone turnover during OTM. CONCLUSIONS: This is the first demonstration that shows that autophagy is induced by orthodontic loading and plays a role during OTM, likely via negative regulation of inflammatory response and bone turnover. Exploring roles of autophagy in OTM holds great promise, as aberrant autophagy is associated with periodontal disease and its related systemic inflammatory disorders.


Assuntos
Osteoclastos , Técnicas de Movimentação Dentária , Animais , Autofagia , Remodelação Óssea , Masculino , Camundongos , Dente Molar
3.
Sensors (Basel) ; 20(24)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33353006

RESUMO

Glycated hemoglobin (HbA1c) levels are an important index for the diagnosis and long-term control of diabetes. This study is the first to use a direct and label-free photoelectric biosensor to determine HbA1c using bacteriorhodopsin-embedded purple membranes (PM) as a transducer. A biotinylated PM (b-PM) coated electrode that is layered with protein A-oriented antibodies against hemoglobin (Hb) readily captures non-glycated Hb (HbA0) and generates less photocurrent. The spectra of bacteriorhodopsin and Hb overlap so the photocurrent is reduced because of the partial absorption of the incident light by the captured Hb molecules. Two HbA0 and HbA1c aptasensors that are prepared by conjugating specific aptamers on b-PM coated electrodes single-step detect HbA0 and HbA1c in 15 min, without cross reactivity, with detection limits of ≤0.1 µg/mL and a dynamic range of 0.1-100 µg/mL. Both aptasensors exhibit high selectivity and long-term stability. For the clinical samples, HbA0 concentrations and HbA1c levels that are measured with aptasensors correlate well with total Hb concentrations and the HbA1c levels that are determined using standard methods (correlation gradient = 0.915 ± 0.004 and 0.981 ± 0.001, respectively). The use of these aptasensors for diabetes care is demonstrated.


Assuntos
Bacteriorodopsinas , Técnicas Biossensoriais , Animais , Hemoglobinas Glicadas/análise , Humanos , Coelhos , Transdutores
4.
J Prosthodont ; 28(1): 15-21, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29528175

RESUMO

PURPOSE: The purpose of this randomized controlled clinical trial was to investigate the prosthetic outcomes of posterior implant-supported single crowns (SCs) with a modified monolithic zirconia or metal-ceramic design at 1 year of loading. MATERIALS AND METHODS: Forty participants with 73 dental implants in need of at least 1 maxillary or mandibular posterior implant-supported SC were consecutively selected for this study. The included participants were randomly divided into modified monolithic zirconia (MMZ) and metal-ceramic (MC) groups. The implant-supported SCs were examined after 1 year for survival and technical complications. Descriptive statistics were used to illustrate the data, and the association associated risks of complications were estimated using the logistic regression model with Firth's approach for rare outcome (α = 0.05). RESULTS: During the observation period, 2 participants in the MC group were lost to follow-up. A total of 38 participants with 70 posterior implant-supported SCs (36 and 34 SCs in the MMZ and MC groups respectively) completed the 1-year follow-up examination. One implant failed in the MMZ group. The 1-year survival rates for implants and crowns were both 97.2% in the MMZ group. The survival rates for implants and crowns were both 100% in the MC group. One screw loosening event was observed in one screw-retained SC in the MMZ group; however, 8 complication events occurred in 7 SCs in the MC group. Therefore, the complication-free rates were 97.1% and 79.4% in the MMZ and MC SCs respectively. The most common complication in the MC group was screw loosening (14.7%), followed by loss of retention (5.9%), and ceramic fracture (2.9%). Significantly more technical complications were observed in the MC SCs than MMZ SCs (p = 0.0432). CONCLUSION: The modified monolithic zirconia design applied to the posterior implant-supported SCs had a significantly lower technical complication rate than did the metal-ceramic one.


Assuntos
Coroas , Prótese Dentária Fixada por Implante , Ligas Metalo-Cerâmicas , Zircônio , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Biochim Biophys Acta Proteins Proteom ; 1866(2): 379-386, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28911812

RESUMO

BACKGROUND: Functional and biophysical constraints can cause different levels of sequence conservation in proteins. Previously, structural properties, e.g., relative solvent accessibility (RSA) and packing density of the weighted contact number (WCN), have been found to be related to protein sequence conservation (CS). The Voronoi volume has recently been recognized as a new structural property of the local protein structural environment reflecting CS. However, for surface residues, it is sensitive to water molecules surrounding the protein structure. Herein, we present a simple structural determinant termed the relative space of Voronoi volume (RSV); it uses the Voronoi volume and the van der Waals volume of particular residues to quantify the local structural environment. METHODS: RSV (range, 0-1) is defined as (Voronoi volume-van der Waals volume)/Voronoi volume of the target residue. The concept of RSV describes the extent of available space for every protein residue. RESULTS: RSV and Voronoi profiles with and without water molecules (RSVw, RSV, VOw, and VO) were compared for 554 non-homologous proteins. RSV (without water) showed better Pearson's correlations with CS than did RSVw, VO, or VOw values. The mean correlation coefficient between RSV and CS was 0.51, which is comparable to the correlation between RSA and CS (0.49) and that between WCN and CS (0.56). CONCLUSIONS: RSV is a robust structural descriptor with and without water molecules and can quantitatively reflect evolutionary information in a single protein structure. Therefore, it may represent a practical structural determinant to study protein sequence, structure, and function relationships.


Assuntos
Proteínas/química , Análise de Sequência de Proteína , Domínios Proteicos , Proteínas/genética , Relação Estrutura-Atividade
6.
J Prosthodont ; 27(2): 108-114, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29086467

RESUMO

PURPOSE: The purpose of this clinical trial was to investigate the clinical outcomes of implant-supported modified monolithic zirconia single crowns (SCs) and short-span fixed dental prostheses (FDPs) after a follow-up of 2 years. MATERIALS AND METHODS: Twenty-seven patients in need of implant-supported SCs or 3-unit FDPs in the posterior maxilla or mandible were consecutively selected for this study. A total of 56 modified monolithic zirconia prostheses including 44 SCs (8 screw-retained, 36 cement-retained) and twelve 3-unit FDPs (5 screw-retained, 7 cement-retained) were included in this study. All patients were followed at 6 months, 12 months, 18 months, and 2 years after placement of the modified monolithic zirconia prostheses. During the follow-up period, all prostheses were evaluated with clinical and radiographic examinations. The following technical parameters were assessed: framework fracture, fracture of veneering porcelain, screw loosening, loss of retention because of prosthesis de-cementation and opposing tooth fracture. RESULTS: No implant was lost during the follow-up period, yielding a 2-year implant survival of 100%. One FDP failed because of framework fracture. The overall prosthesis survival rate was 98.2% after 2 years of clinical service. During the study, 5 complication events were observed in 3 SCs and one FDP, including one fracture of veneering porcelain and 2 screw loosenings in 3 SCs, and loss of retention and opposing tooth fracture in the same FDP. Therefore, the complication-free rate of prostheses was 91.1%. CONCLUSION: According to the results of this study, the modified monolithic zirconia design used in this study resulted in a favorable short-term outcome for posterior implant-supported SCs and 3-unit FDPs.


Assuntos
Coroas , Prótese Dentária Fixada por Implante/métodos , Prótese Parcial Fixa , Zircônio , Coroas/efeitos adversos , Prótese Dentária Fixada por Implante/efeitos adversos , Falha de Restauração Dentária/estatística & dados numéricos , Prótese Parcial Fixa/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Radiografia Dentária
7.
Proteins ; 85(9): 1713-1723, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28597979

RESUMO

Residues that are crucial to protein function or structure are usually evolutionarily conserved. To identify the important residues in protein, sequence conservation is estimated, and current methods rely upon the unbiased collection of homologous sequences. Surprisingly, our previous studies have shown that the sequence conservation is closely correlated with the weighted contact number (WCN), a measure of packing density for residue's structural environment, calculated only based on the Cα positions of a protein structure. Moreover, studies have shown that sequence conservation is correlated with environment-related structural properties calculated based on different protein substructures, such as a protein's all atoms, backbone atoms, side-chain atoms, or side-chain centroid. To know whether the Cα atomic positions are adequate to show the relationship between residue environment and sequence conservation or not, here we compared Cα atoms with other substructures in their contributions to the sequence conservation. Our results show that Cα positions are substantially equivalent to the other substructures in calculations of various measures of residue environment. As a result, the overlapping contributions between Cα atoms and the other substructures are high, yielding similar structure-conservation relationship. Take the WCN as an example, the average overlapping contribution to sequence conservation is 87% between Cα and all-atom substructures. These results indicate that only Cα atoms of a protein structure could reflect sequence conservation at the residue level.


Assuntos
Sequência de Aminoácidos/genética , Sequência Conservada/genética , Conformação Proteica , Proteínas/química , Modelos Moleculares , Proteínas/genética
8.
J Chem Inf Model ; 56(12): 2287-2291, 2016 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-27976886

RESUMO

The structure of a protein determines its biological function(s) and its interactions with other factors; the binding regions tend to be conserved in sequence and structure, and the interacting residues involved are usually in close 3D space. The Protein Data Bank currently contains more than 110 000 protein structures, approximately one-third of which contain metal ions. Identifying and characterizing metal ion-binding sites is thus essential for investigating a protein's function(s) and interactions. However, experimental approaches are time-consuming and costly. The web server reported here was built to predict metal ion-binding residues and to generate the predicted metal ion-bound 3D structure. Binding templates have been constructed for regions that bind 12 types of metal ion-binding residues have been used to construct binding templates. The templates include residues within 3.5 Šof the metal ion, and the fragment transformation method was used for structural comparison between query proteins and templates without any data training. Through the adjustment of scoring functions, which are based on the similarity of structure and binding residues. Twelve kinds of metal ions (Ca2+, Cu2+, Fe3+, Mg2+, Mn2+, Zn2+, Cd2+, Fe2+, Ni2+, Hg2+, Co2+, and Cu+) binding residues prediction are supported. MIB also provides the metal ions docking after prediction. The MIB server is available at http://bioinfo.cmu.edu.tw/MIB/ .


Assuntos
Metais/metabolismo , Simulação de Acoplamento Molecular , Proteínas/metabolismo , Sítios de Ligação , Cátions/metabolismo , Bases de Dados de Proteínas , Internet , Conformação Proteica , Proteínas/química , Software
9.
J Dent Sci ; 19(3): 1673-1679, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39035261

RESUMO

Background/purpose: Interproximal contact loss may lead to food impaction and result in subsequently periodontal complications. The purpose of this prospective study was to investigate the peri-implant parameters of posterior implant-supported single crowns (SCs) with and without mesial proximal contact loss after 2 years of follow-up. Material and methods: Twenty-six patients with a total of 40 posterior implant-supported SCs with mesial adjacent natural teeth were observed for 24 months after crown insertion. The mesial proximal contacts were assessed by dental floss, then were classified as tight, weak, and open contacts. The following peri-implant parameters were evaluated, including modified plaque index (MPI), modified gingival index (MGI), and probing depth (PD) were conducted at six sites per tooth (mesiofacail, midfacial, distofacial, mesiolingual, mid-lingual and distolingual) in the 6-, 12-, 18- and 24-month following visits. Furthermore, radiographs were taken regularly in 12- and 24-month recall sections for measuring the marginal bone loss (MBL). Results: At 12-month observation, the incidence rates of weak and open contacts were 22.5 % and 12.5 %; whereas after 24 months of clinical service, the rates came up with 12.9 % and 25.6 %, respectively. No significant differences were found between the tight, weak, and open contact groups in the parameters of MPI, MGI, or PD (P > 0.05) at 12- and 24-month follow-up. None of the mean differences of the peri-implant parameters: MPI, MGI, PD and MBL had significant differences between the tight, weak, and open contact groups after 1 and 2 years of clinical service (P > 0.05). Conclusion: The presence of open, weak, and tight mesial proximal contacts had no significant effects on the peri-implant tissue conditions.

10.
J Prosthodont Res ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39198202

RESUMO

PURPOSE: Poor contour of the implant restoration causes plaque accumulation and increases the risk of peri-implantitis. This study aimed to investigate whether the prosthodontic components of dental implants were associated with the prevalence of peri-implantitis. METHODS: We enrolled 185 patients with 348 implants who underwent at least 1-year follow-up after the delivery of the prosthesis from February 2010 to January 2021. Demographic data of the patients and implants and the follow-up period were recorded. The emergence angle, type of cervical crown contour, and contour angle were analyzed using annual bite-wing radiographs. Peri-implantitis in this study was diagnosed if the peri-implant bone loss was greater than 2 mm between the bite-wing radiographs taken at baseline and the latest. Chi-square test, two-sample t-test, and multivariate logistic regression were used to investigate the differences and odds ratios between the peri-implantitis and non-peri-implantitis groups. RESULTS: The incidence of peri-implantitis was 14.9% during a follow-up period of 1509 days after the delivery of the prosthesis for at least 1-year. Based on the prevalence of non-peri-implantitis and after adjusting for confounding factors, the risk factors identified were bone types for implants (native bone vs. alveolar ridge preservation: adjusted odds ratio = 2.43, P = 0.04). Sex, arch, and guided bone regeneration vs. alveolar ridge preservation have the potential for a statistical difference. CONCLUSIONS: Compared with implants at alveolar ridge preservation sites, implants in the native bone were more prone to peri-implantitis. Further randomized controlled trials are required to determine these associations.

11.
J Dent Sci ; 18(3): 1206-1211, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37404630

RESUMO

Background/Purpose: The digital impression is a promising technique in prosthodontic treatment. However, the influencing factors of patient comfort is lacking, and the evidence of crown quality is mostly based on in vitro studies. The purpose of this double-blinded clinical trial was to compare the patient satisfaction and crown accuracy of two different intraoral scanners (IOSs) for the fabrication of all-ceramic single crowns (SCs). Materials and methods: Participants in need of posterior tooth-supported SCs were enrolled. Each patient received quadrant scan by both the Metal Industries Research and Development Centre (MIRDC) IOS and Carestream CS3500 in a random sequence. After scanning, participants had to fill in a 6-item perception questionnaire that based on 5-point Likert scale for two IOSs. Both data were sent to a dental laboratory to fabricate the monolithic lithium disilicate SCs. The crown accuracy including marginal fit, proximal contact, occlusal contact, and general satisfaction were accessed based on 5-point scale. Results: A total of 15 participants with 40 crowns (20 SCs in each group) were investigated. Regarding to patient satisfaction, there was no statistically significant difference in total score between MIRDC and Carestream IOSs (23.6 ± 3.79 vs 23.1 ± 4.28, P = 0.36). In terms of crown accuracy, there was significantly different in total score and all the evaluated parameters between MIRDC and Carestream groups (6.1 ± 1.41 vs 13.3 ± 3.75, P < 0.001). Conclusion: Both MIRDC and Carestream IOSs can provide good patient satisfaction during intraoral scanning. The Carestream IOS obtains better accuracy for the fabrication of all-ceramic SCs.

12.
Implant Dent ; 21(3): 171-4, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22513500

RESUMO

PURPOSE: This case report describes a biologic complication related to polylactic acid membrane in guided bone regeneration (GBR). MATERIALS AND METHODS: A healthy 42-year-old patient complained of persistent discomfort of the maxillary anterior gingiva. Clinical examination and radiographs showed severe periodontal destruction of teeth 7 through 10. Teeth extraction was followed by early implant placement with GBR. RESULTS: Four months later, severe bone resorption was observed upon surgical exposure. A second GBR was performed. Wound healing progressed uneventfully and an implant-supported fixed partial denture was later loaded. CONCLUSION: We presume that this complication was a foreign body reaction to the polylactic acid membrane. Such a reaction can affect soft and hard tissue healing following GBR. Long-term follow-up is needed to determine stability of the results.


Assuntos
Implantes Absorvíveis/efeitos adversos , Perda do Osso Alveolar/etiologia , Reação a Corpo Estranho/etiologia , Regeneração Tecidual Guiada Periodontal/métodos , Ácido Láctico/efeitos adversos , Polímeros/efeitos adversos , Adulto , Perda do Osso Alveolar/cirurgia , Regeneração Óssea , Prótese Dentária Fixada por Implante , Prótese Parcial Fixa , Humanos , Membranas Artificiais , Poliésteres
13.
IEEE J Transl Eng Health Med ; 8: 2700107, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32974110

RESUMO

Patient and health provider interaction via text messaging (TM) has become an accepted form of communication, often favored by adolescents and young adults. While integration of TM in disease management has aided health interventions and behavior modifications, broader adoption is hindered by expense, fixed reporting schedules, and monotonic communication. A low-cost, flexible TM reporting system (REMOTES) was developed using inexpensive cloud-based services with features of two-way communication, personalized reporting scheduling, and scalable and secured data storage. REMOTES is a template-based reporting tool adaptable to a wide-range of complexity in response formats. In a pilot study, 27 adolescents with sickle cell disease participated to assess feasibility of REMOTES in both inpatient and outpatient settings. Subject compliance with at least one daily self-report pain query was 94.9% (112/118) during inpatient and 91.1% (327/359) during outpatient, with an overall accuracy of 99.2% (970/978). With use of a more complex 8-item questionnaire, 30% (7/21) inpatient and 66.6% (36/54) outpatient responses were reported with 98.1% (51/52) reporting accuracy. All participants expressed high pre-trial expectation (88%) and post-trial satisfaction (89%). The study suggests that cloud-based text messaging is feasible and an easy-of-use solution for low-cost and personalized patient engagement.

14.
J Air Waste Manag Assoc ; 69(2): 131-144, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30067463

RESUMO

This study proposes an easy-to-apply method, the Total Life Cycle Emission Model (TLCEM), to calculate the total emissions from shipping and help ship management groups assess the impact on emissions caused by their capital investment or operation decisions. Using TLCEM, we present the total emissions of air pollutants and greenhouse gases (GHGs) during the 25-yr life cycle of 10 post-Panamax containerships under slow steaming conditions. The life cycle consists of steel production, shipbuilding, crude oil extraction and transportation, fuel refining, bunkering, and ship operation. We calculate total emissions from containerships and compare the effect of emission reduction by using various fuels. The results can be used to differentiate the emissions from various processes and to assess the effectiveness of various reduction approaches. Critical pollutants and GHGs emitted from each process are calculated. If the containerships use heavy fuel oil (HFO), emissions of CO2 total 2.79 million tonnes (Mt), accounting for 95.37% of total emissions, followed by NOx and SOx emissions,which account for 2.25% and 1.30%, respectively.The most significant emissions are from the operation of the ship and originate from the main engine (ME).When fuel is switched to 100% natural gas (NG), SOx, PM10, and CO2 emissions show remarkable reductions of 98.60%, 99.06%, and 21.70%, respectively. Determining the emission factor of each process is critical for estimating the total emissions. The estimated emission factors were compared with the values adopted by the International Maritime Organization (IMO).The proposed TLCEM may contribute to more accurate estimates of total life cycle emissions from global shipping. Implications: We propose a total life cycle emissions model for 10 post-Panamax container ships. Using heavy fuel oil, emissions of CO2 total 2.79 Mt, accounting for approximately 95% of emissions, followed by NOx and SOx emissions. Using 100% natural gas, SOx, PM10, and CO2 emissions reduce by 98.6%, 99.1%, and 21.7%, respectively. NOx emissions increase by 1.14% when running a dual fuel engine at low load in natural gas mode.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental/métodos , Gases de Efeito Estufa/análise , Petróleo/análise , Navios , Emissões de Veículos , Poluentes Ambientais/análise , Óleos Combustíveis/análise , Humanos , Gás Natural/análise , Emissões de Veículos/análise , Emissões de Veículos/prevenção & controle
16.
J Dent Sci ; 13(4): 301-310, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30895138

RESUMO

BACKGROUND/PURPOSE: With the technology of dental prostheses and materials progress, the bond durability of the all-ceramic restoration system plays an important role in the oral environment. The purpose of this study was to evaluate the influence of the parameters of blasting on the shear bond strength between zirconia and pressed veneer ceramics. MATERIALS AND METHODS: Zirconia was blasted with different alumina particle size subjected to two types of applied pressures. Heat-pressed and layered veneer ceramic blocks were served as an experimental group and control group, respectively. The shear strength of specimens after thermocycling for 20,000 times was also investigated to simulate oral environment. RESULTS: The results indicated that the surface roughness was increased significantly (P < 0.05) with increasing particle size of alumina and blasting pressure. The alumina particle size had statistically significant influence (P < 0.05) on shear strength of heat-pressed groups. Among heat-pressed ceramic specimens, the highest and lowest shear strength could be obtained when 50 µm of alumina was used at pressure of 0.3 MPa and 110 µm of alumina was used at 0.5 MPa, respectively. The negligible effect of thermal cycle on shear strength of heat-pressed groups can be seen. CONCLUSION: Blasting with 50 µm of alumina at 0.3 MPa could enhance the bond strength between zirconia and veneer ceramics.

17.
J Air Waste Manag Assoc ; 68(6): 588-597, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29215965

RESUMO

In this study, the nitrogen oxide (NOx) emission factors and total NOx emissions of two groups of post-Panamax container ships operating on a long-term slow-steaming basis along Euro-Asian routes were calculated using both the probability density function of engine power levels and the NOx emission function. The main engines of the five sister ships in Group I satisfied the Tier I emission limit stipulated in MARPOL (International Convention for the Prevention of Pollution from Ships) Annex VI, and those in Group II satisfied the Tier II limit. The calculated NOx emission factors of the Group I and Group II ships were 14.73 and 17.85 g/kWhr, respectively. The total NOx emissions of the Group II ships were determined to be 4.4% greater than those of the Group I ships. When the Tier II certification value was used to calculate the average total NOx emissions of Group II engines, the result was lower than the actual value by 21.9%. Although fuel consumption and carbon dioxide (CO2) emissions were increased by 1.76% because of slow steaming, the NOx emissions were markedly reduced by 17.2%. The proposed method is more effective and accurate than the NOx Technical Code 2008. Furthermore, it can be more appropriately applied to determine the NOx emissions of international shipping inventory. IMPLICATIONS: The usage of operating power probability density function of diesel engines as the weighting factor and the NOx emission function obtained from test bed for calculating NOx emissions is more accurate and practical. The proposed method is suitable for all types and purposes of diesel engines, irrespective of their operating power level. The method can be used to effectively determine the NOx emissions of international shipping and inventory applications and should be considered in determining the carbon tax to be imposed in the future.


Assuntos
Poluentes Atmosféricos/análise , Óxidos de Nitrogênio/análise , Navios , Emissões de Veículos/análise , Algoritmos , Dióxido de Carbono/análise
18.
Biomed Res Int ; 2018: 8582901, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29854800

RESUMO

The aim of this population-based cohort study was to explore postoperative renal outcomes of patients receiving pyelolithotomy versus percutaneous nephrolithotomy (PCNL). Data were retrieved from the Taiwan National Health Insurance Research Database. During the period from Jan 1, 1998, to Dec 31, 2012, there were 2549 and 21654 patients who underwent pyelolithotomy and PCNL, respectively. The postoperative incidence of new diagnosed end stage renal disease (ESRD) was statistically analyzed and compared between the pyelolithotomy and PCNL groups. The perioperative complications of two groups were also analyzed. In comparison to pyelolithotomy, PCNL achieved lower new diagnosed ESRD (1.38% versus 2.28%, p = 0.0004). Patients receiving PCNL had significantly higher rates of preoperative hypertension, diabetes mellitus, pulmonary disease, cerebrovascular disease, and coronary artery disease. The hospital stay was shorter in PCNL groups compared with pyelolithotomy groups (8.31 days versus 12.59 days, p = 0.0006). In conclusion, PCNL contributed to lower rates of new diagnosed ESRD and hospital stay when compared to pyelolithotomy.


Assuntos
Rim/cirurgia , Nefrolitotomia Percutânea , Cuidados Pós-Operatórios , Estudos de Coortes , Demografia , Feminino , Humanos , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/etiologia , Falência Renal Crônica/mortalidade , Masculino , Pessoa de Meia-Idade , Nefrolitotomia Percutânea/efeitos adversos , Nefrolitotomia Percutânea/mortalidade , Probabilidade , Resultado do Tratamento
19.
J Air Waste Manag Assoc ; 67(10): 1146-1157, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28722541

RESUMO

An important marine pollution issue identified by the International Maritime Organization (IMO) is NOx emissions; however, the stipulated method for determining the NOx certification value does not reflect the actual high emission factors of slow-speed two-stroke diesel engines over long-term slow steaming. In this study, an accurate method is presented for calculating the NOx emission factors and total amount of NOx emissions by using the actual power probabilities of the diesel engines in four types of bulk carriers. The proposed method is suitable for all types and purposes of diesel engines, is not restricted to any operating modes, and is highly accurate. Moreover, it is recommended that the IMO-stipulated certification value calculation method be modified accordingly to genuinely reduce the amount of NOx emissions. The successful achievement of this level of reduction will help improve the air quality, especially in coastal and port areas, and the health of local residents. IMPLICATIONS: As per the IMO, the NOx emission certification value of marine diesel engines having a rated power over 130 kW must be obtained using specified weighting factor (WF)-based calculation. However, this calculation fails to represent the current actual situation. Effective emission reductions of 6.91% (at sea) and 31.9% (in ports) were achieved using a mathematical model of power probability functions. Thus, we strongly recommend amending the certification value of NOx Technical Code 2008 (NTC 2008) by removing the WF constraints, such that the NOx emissions of diesel engines is lower than the Tier-limits at any load level to obtain genuine NOx emission reductions.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Gasolina/análise , Óxido Nitroso/análise , Navios , Emissões de Veículos/análise , Monitoramento Ambiental , Probabilidade
20.
IEEE Trans Biomed Eng ; 64(2): 263-273, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27740470

RESUMO

OBJECTIVE: Rapid advances of high-throughput technologies and wide adoption of electronic health records (EHRs) have led to fast accumulation of -omic and EHR data. These voluminous complex data contain abundant information for precision medicine, and big data analytics can extract such knowledge to improve the quality of healthcare. METHODS: In this paper, we present -omic and EHR data characteristics, associated challenges, and data analytics including data preprocessing, mining, and modeling. RESULTS: To demonstrate how big data analytics enables precision medicine, we provide two case studies, including identifying disease biomarkers from multi-omic data and incorporating -omic information into EHR. CONCLUSION: Big data analytics is able to address -omic and EHR data challenges for paradigm shift toward precision medicine. SIGNIFICANCE: Big data analytics makes sense of -omic and EHR data to improve healthcare outcome. It has long lasting societal impact.


Assuntos
Bases de Dados Factuais , Registros Eletrônicos de Saúde , Genômica , Informática Médica , Medicina de Precisão , Humanos
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