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1.
BMC Oral Health ; 24(1): 48, 2024 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-38191341

RESUMEN

BACKGROUND: The aim of this study was to evaluate the condylar morphological changes after orthodontic treatment in adult patients with Class II malocclusion using a Cone-beam computed tomography (CBCT). METHODS: Images of twenty-eight adult patients with Class II malocclusion who have no temporomandibular symptoms were involved in this study. To analyze the post-treatment changes in condylar morphology, mimics 17.0 software was used to measure several values and reconstruct the three-dimensional condyle, including height of the condyle, area and bone mineral density of the maximum axial and sagittal section, volume and bone mineral density of the three-dimensional condyle and condylar head before and after orthodontic treatment. Using SPSS 19.0 software package Paired t-test was applied for comparison of condylar morphology analysis between pre-treatment and post-treatment. RESULTS: Height of condylar head increase significant (P < .05). Bone mineral density showed a decrease in the maximum axial and sagittal section, three-dimensional condyle and condylar head (P < .01). Evaluation of volume revealed that volume of both condyle and condylar head decrease considerably (P < .05). No significant difference was detected in other values ((P > .05). CONCLUSION: Condylar volume decreased and height of condylar head have changed, so we speculated that adaptive bone remodeling of the condyle occurs.


Asunto(s)
Densidad Ósea , Maloclusión Clase II de Angle , Adulto , Humanos , Tomografía Computarizada de Haz Cónico , Atención Odontológica , Maloclusión Clase II de Angle/diagnóstico por imagen , Maloclusión Clase II de Angle/terapia , Huesos
2.
Inorg Chem ; 62(14): 5700-5706, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-36966515

RESUMEN

Low-cost high-efficiency H2 evolution is indispensable for its large-scale applications in the future. In the research, we expect to build high active photocatalysts for sunlight-driven H2 production by surface engineering to adjust the work function of photocatalyst surfaces, adsorption/desorption ability of substrates and products, and reaction activation energy barrier. Single-atom Pt-doped TiO2-x nanosheets (NSs), mainly including two facets of (001) and (101), with loading of Pt nanoparticles (NPs) at their edges (Pt/TiO2-x-SAP) are successfully prepared by an oxygen vacancy-engaged synthetic strategy. According to the theoretical simulation, the implanted single-atom Pt can change the surface work function of TiO2, which benefits electron transfer, and electrons tend to gather at Pt NPs adsorbed at (101) facet-related edges of TiO2 NSs for H2 evolution. Pt/TiO2-x-SAP exhibits ultrahigh photocatalytic performance of hydrogen evolution from dry methanol with a quantum yield of 90.8% that is ∼1385 times higher than pure TiO2-x NSs upon 365 nm light irradiation. The high H2 generation rate (607 mmol gcata-1 h-1) of Pt/TiO2-x-SAP is the basis for its potential applications in the transportation field with irradiation of UV-visible light (100 mW cm-2). Finally, lower adsorption energy for HCHO on Ti sites originated from TiO2 (001) doping single-atom Pt is responsible for high selective dehydrogenation of methanol to HCHO, and H tends to favorably gather at Pt NPs on the TiO2 (101) surface to produce H2.

3.
BMC Oral Health ; 23(1): 28, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36650491

RESUMEN

BACKGROUND: It is difficult for orthodontists to accurately predict the growth trend of the mandible in children with anterior crossbite. This study aims to develop a deep learning model to automatically predict the mandibular growth result into normal or overdeveloped using cephalometric radiographs. METHODS: A deep convolutional neural network (CNN) model was constructed based on the algorithm ResNet50 and trained on the basis of 256 cephalometric radiographs. The prediction behavior of the model was tested on 40 cephalograms and visualized by equipped with Grad-CAM. The prediction performance of the CNN model was compared with that of three junior orthodontists. RESULTS: The deep-learning model showed a good prediction accuracy about 85%, much higher when compared with the 54.2% of the junior orthodontists. The sensitivity and specificity of the model was 0.95 and 0.75 respectively, higher than that of the junior orthodontists (0.62 and 0.47 respectively). The area under the curve value of the deep-learning model was 0.9775. Visual inspection showed that the model mainly focused on the characteristics of special regions including chin, lower edge of the mandible, incisor teeth, airway and condyle to conduct the prediction. CONCLUSIONS: The deep-learning CNN model could predict the growth trend of the mandible in anterior crossbite children with relatively high accuracy using cephalometric images. The deep learning model made the prediction decision mainly by identifying the characteristics of the regions of chin, lower edge of the mandible, incisor teeth area, airway and condyle in cephalometric images.


Asunto(s)
Aprendizaje Profundo , Maloclusión , Humanos , Niño , Mandíbula/diagnóstico por imagen , Redes Neurales de la Computación , Radiografía , Maloclusión/diagnóstico por imagen
4.
Angew Chem Int Ed Engl ; 60(47): 24849-24853, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34435428

RESUMEN

Metal-organic frameworks (MOFs) provide a platform to design new heterogeneous catalysts for catalytic CO2 reduction, but selective formation of C2 valuable liquid fuel products remains a challenge. Herein, we propose a strategy to synthesize composites by integrating MoS2 nanosheets into hierarchically porous defective UiO-66 (d-UiO-66) to form Mo-O-Zr bimetallic sites on the interfaces between UiO-66 and MoS2 . The active interfaces are favorable for the efficient transfer of photo-generated charge carriers and for promoting the activity, whereas, the synergy of the components at the interfaces achieves selectivity for C2 production. The d-UiO-66/MoS2 composite facilitates the photo-catalytic conversion of gas phase CO2 and H2 O to CH3 COOH under visible light irradiation without any other adducts. The evolution rate and selectivity of CH3 COOH reached 39.0 µmol g-1 h-1 and 94 %, respectively, without any C1 products, suggesting a new approach for the design of highly efficient photocatalysts of CO2 for C2 production. Theoretical calculations demonstrate the charge-polarized Zr-O-Mo aided the C-C coupling process with the largely reduced energy barrier.

5.
BMC Oral Health ; 20(1): 350, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33261594

RESUMEN

BACKGROUND: This is a retrospective study that compares mandibular growth changes in skeletal Class II patients treated by rapid maxillary expansion (RME) and following fixed appliance with those patients treated by Twin-Block (TB) and following fixed appliance. METHODS: Fourteen patients treated by RME and following fixed appliance were included into the RME group. Fifteen patients treated by Twin-Block and following fixed appliance were included into the TB group. Lateral cephalometric radiographs taken before treatment and immediately after fixed appliance treatment were used to evaluate mandibular growth effects. RESULTS: The starting forms of the patients in the two groups were examined to be of good comparability. The mandibular length increased significantly in both groups as measured by Co-Gn, Go-Gn and Ar-Gn, but the TB group didn't show more mandibular growth than the RME group (P > 0.05). Skeletal changes of the mandible in vertical dimension were different in the two groups. The change in FMA was 0.35° in the RME group, while the change was 2.65° in the TB group (P < 0.001). The change in LAFH was 5.14 mm in the RME group, significantly smaller than the change of 10.19 mm in the TB group (P < 0.001). CONCLUSION: The investigated Phase I treatment with RME followed by Phase II treatment of fixed appliance achieved the same increases in sagittal mandibular growth and facial profile improvements as the Twin-Block therapy. The treatment with RME followed by fixed appliance was better for vertical control, while the treatment with Twin-Block followed by fixed appliance significantly increased the mandibular plane angle.


Asunto(s)
Maloclusión Clase II de Angle , Técnica de Expansión Palatina , Cefalometría , Humanos , Maloclusión Clase II de Angle/diagnóstico por imagen , Maloclusión Clase II de Angle/terapia , Mandíbula/diagnóstico por imagen , Diseño de Aparato Ortodóncico , Estudios Retrospectivos , Resultado del Tratamiento
6.
Am J Orthod Dentofacial Orthop ; 155(3): 398-410, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30826043

RESUMEN

This case report describes the induced ankylosis of the primary canines for use as absolute anchorage for maxillary protraction. The patient was a young boy with Class III malocclusion and cleft soft palate. The final occlusion was esthetic, functional, healthy, and stable 4 years after treatment.


Asunto(s)
Fisura del Paladar/cirugía , Diente Canino , Maloclusión de Angle Clase III/terapia , Métodos de Anclaje en Ortodoncia , Ortodoncia Correctiva/métodos , Paladar Blando/anomalías , Anquilosis del Diente , Cefalometría , Niño , Humanos , Masculino , Maloclusión de Angle Clase III/diagnóstico por imagen , Paladar Blando/cirugía , Radiografía Panorámica
7.
J Oral Pathol Med ; 45(7): 534-8, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26710939

RESUMEN

BACKGROUND: This study aims to investigate spatial and temporal changes in cadherin-11 (CAD-11) expression and their effects on cartilage degeneration in the temporomandibular joint (TMJ) of guinea pigs with spontaneous osteoarthritis (OA). METHODS: Dunkin-Hartley (DH) and Bristol strain 2 (BS2) guinea pigs at ages of 1, 3, 6, 9, and 12 months were categorized into two groups and analyzed. The bilateral TMJ condyles of DH and BS2 guinea pigs were harvested and fixed. The distribution and expression profiles of CAD-11, collagen type II, and matrix metalloproteinase 3 (MMP-3) were detected by immunohistological assays. Histological micrographs of the condyle cartilage were obtained and analyzed. RESULTS: Osteoarthritis can be spontaneously induced by mechanical stress in DH guinea pigs. The main histopathological changes in the TMJ structure and increased expression of MMP-3 occurred within 6-9 months of ages in DH guinea pigs with spontaneous OA. By contrast, minimal to mild cartilage degradations were observed in the TMJ of BS2 guinea pigs even at the age of 12 months. From as early as 3 months of age, the expression levels of CAD-11 were upregulated in the TMJ of DH guinea pigs compared with those in BS2 animals. CAD-11 expression differed between the two groups at 12 months of age. CONCLUSIONS: Increased CAD-11 expression within cartilage is associated with the development and progression of OA between the two strains of guinea pigs. Therefore, CAD-11 expression in TMJ could be an important predisposing factor for the development of spontaneous OA.


Asunto(s)
Cadherinas/biosíntesis , Cartílago/metabolismo , Osteoartritis/patología , Articulación Temporomandibular/metabolismo , Animales , Cartílago/patología , Colágeno Tipo II/biosíntesis , Modelos Animales de Enfermedad , Cobayas , Inmunohistoquímica , Cóndilo Mandibular , Metaloproteinasa 3 de la Matriz/biosíntesis , Estrés Mecánico , Articulación Temporomandibular/patología , Regulación hacia Arriba
8.
Chem Commun (Camb) ; 60(43): 5650-5653, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38726591

RESUMEN

Developing an intermediate-temperature solid oxide fuel cell (IT-SOFC) is one of the most promising ways of achieving carbon neutrality, but its air-electrode is restricted by the conflict between the sluggish catalytic activity and durability. Herein, an A-site high-entropy perovskite composite La0.2Ba0.2Sr0.2Ca0.2Ce0.2-xCoO3-δ-xCeO2 (LBSCCC-CeO2) air-electrode material is fabricated via a one-step self-constructing strategy, which shows excellent oxygen reduction activity and stability due to the high-entropy structure and the synergy effect between LBSCCC and interfacial CeO2. This work provides a new way of fabricating high-performance air-electrodes in IT-SOFCs.

9.
Oral Health Prev Dent ; 21(1): 211-218, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37272598

RESUMEN

PURPOSE: To research the role of microRNA (miR)-152 in the pathogenesis of pulpitis using a cell model based on human dental pulp cells (HDPCs) treated with lipopolysaccharides (LPS). MATERIALS AND METHODS: The biological activity of HDPCs infected by LPS was measured using a cell counting kit (CCK-8), Transwell test, flow cytometry, and fluorescent quantitative PCR. The concentration of superoxide dismutase (SOD) and malondialdehyde (MDA) was evaluated using an assay kit, the levels of interleukin (IL)-1ß and IL-6 were measured by enzyme-linked immunosorbent assay (ELISA), and the targeting relationship between SMAD5 and miR-152 was measured by the double-luciferase report test. The expression of cell cycle-related CyclinD1 and BAX was assessed by PCR. By plotting a receiver operating characteristic (ROC) curve, the diagnostic value of miR-152 was shown. RESULTS: The level of miR-152 in HDPCs induced by LPS decreased, while the level of SMAD5 increased. After overexpressing miR-152 in LPS-induced HDPCs, the viability was elevated, the apoptosis rate decreased, CyclinD1 was elevated, BAX diminished, the inflammatory cytokines (IL-6 and IL-1ß) were inhibited, the activity of SOD increased, and the MDA content decreased. miR-152 targeted regulation of SMAD5, and SMAD5 modulated the effects of miR-152 on cell viability, apoptosis, inflammation, and the oxidative response of HDPCs. Reduced miR-152 expression was verified in patients with pulpitis, which could be a biomarker for pulpitis. CONCLUSION: miR-152 was found to be a biomarker correlated with the pathogenesis of pulpitis and the biological behaviour of HDPCs.


Asunto(s)
MicroARNs , Pulpitis , Humanos , Pulpitis/metabolismo , Interleucina-6/metabolismo , Interleucina-6/farmacología , Lipopolisacáridos/farmacología , Pulpa Dental/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Proteína X Asociada a bcl-2/farmacología , MicroARNs/genética , MicroARNs/metabolismo , Proteína Smad5/metabolismo , Proteína Smad5/farmacología
10.
Chem Commun (Camb) ; 59(54): 8456-8459, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37337856

RESUMEN

Herein, we created defects on NH2-MIL-125 to form more nodes of grafted metals, and synthesized a series of hybrid materials (Cu/d-NH2-MIL-125 and CuNPs/d-NH2-MIL-125 with 1,2, and 4 wt % of Cu nanoparticles) that were used as photocatalysts of the hydrogen evolution reaction and dehydrogenation of tetrahydroisoquinoline. At the optimal relative amount of Cu, namely 2 wt %, the hydrogen evolution reaction and dehydrogenation of tetrahydroisoquinoline showed rates of 1326.55 µmol g-1 h-1 and 427.15 µmol g-1 h-1, respectively. This new photocatalyst could effectively improve the e-/h+ separation efficiency, enriching the investigation of MOFs in the field of photocatalytic hydrogen evolution.

11.
RSC Adv ; 13(40): 28097-28103, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37746342

RESUMEN

Defects formed by halide ion escape and wettability of the perovskite absorber are essential limiting factors in achieving high performance of perovskite solar cells (PSCs). Herein, a series of ionic organic modulators are designed to contain halide anions to prevent defect formation and improve the surface tension of the perovskite absorber. It was found that the surface modulator containing Br anions is the most effective one due to its capability in bonding with the undercoordinated Pb2+ ions to reduce charge recombination. Moreover, this surface modulator effectively creates a suitable energy level between the perovskite and hole transport layer to promote carrier transfer. In addition, the surface modulator forms a chemisorbed capping layer on the perovskite surface to improve its hydrophobicity. As a result, the efficiency of PSCs based on surface modulators containing Br anion enhances to 23.32% from 21.08% of the control device. The efficiency of unencapsulated PSCs with a surface modulator retains 75.42% of its initial value under about 35% humidity stored in the air for 28 days, while the control device only maintained 44.49% of its initial efficiency. The excellent stability originates from the hydrophobic perovskite surface after capping the surface modulator.

12.
J Colloid Interface Sci ; 606(Pt 1): 800-807, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34419819

RESUMEN

All-inorganic perovskite materials (Typically: CsPbI2Br) have attracted enormous attention due to their illustrious thermal stability and appropriate bandgap, and their use in perovskite solar cells (PSCs) has been extensively investigated. However, the inevitable defects of the perovskite layer, energy level mismatch between perovskite and carbon electrodes, and the phase instability of CsPbI2Br limit the power conversion efficiency (PCE) and stability of carbon-based CsPbI2Br PSCs. Herein, we demonstrate a simple and effective strategy for regulating energy level, inhibiting carrier recombination, and delaying the degradation of perovskite by modifying the surface of CsPbI2Br with a new type of 2D perovskite Cs2PtI6. The carbon-based CsPbI2Br PSCs achieve a higher PCE (13.69 %) than the control device (11.10 %). The excellent matching of the energy level and suppression of charge carrier recombination should be responsible for the improvement in efficiency. Furthermore, the excellent hydrophobic performance of Cs2PtI6 enhances the moisture resistance of the device. This study provides a potential strategy for improving the performance and stability of all-inorganic CsPbI2Br PSCs.

13.
PhytoKeys ; 174: 1-12, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36760878

RESUMEN

A newly discovered natural hybrid, Iris×ampliflora Y.E. Xiao, F.Y. Yu & X.F. Chen (Iridaceae: subgenus LimnirissectionLophiris) from Chongqing, China, is described and illustrated. This hybrid is morphologically similar to I.japonica Thunb. and I.wattii Baker, but can be distinguished by its giant leaves and large purple flowers. Phylogenetic trees based on cpDNA data support the separation of I.×ampliflora from other closely related species in the section Lophiris. According to its morphological features, molecular systematic evidence and chromosome data, we speculate that I.×ampliflora [31 chromosomes] likely is a new hybrid between I.japonica [2n = 32] and I.wattii [2n = 30].

14.
ACS Appl Mater Interfaces ; 13(16): 18619-18626, 2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33848135

RESUMEN

Safe storage and transportation of H2 is a fundamental requirement for its wide applications in the future. Controllable release of high-purity H2 from a stable storage medium such as CH3OH before use offers an efficient way of achieving this purpose. In our case, Cu nanoclusters uniformly dispersed onto (001) surfaces of TiO2 nanosheets (TiO2/Cu) are selectively prepared by thermal treatment of HKUST-1 loaded TiO2 nanosheets. One of the TiO2/Cu composites, TiO2/Cu_50, exhibits remarkably high activity toward the selective dehydrogenation of CH3OH to HCHO with a H2 evolution rate of 17.8 mmol h-1 per gram of catalyst within a 16-h photocatalytic reaction (quantum efficiency at 365 nm: 16.4%). Theoretical calculations reveal that interactions of Cu nanoclusters with TiO2 could affect their electronic structures, leading to higher adsorption energy of CH3OH at Ti sites and a lower barrier for the dehydrogenation of CH3OH by the synergistic effect of Cu nanoclusters and TiO2, and lower Gibbs free energy for desorption HCHO and H2 as well.

15.
ChemSusChem ; 14(21): 4776-4782, 2021 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-34435455

RESUMEN

Power conversion efficiencies (PCEs) of up to 25.5 % have been reported for perovskite solar cells (PSCs). Thus, they have shown great potential for commercial applications. Therefore, simplifying technological process and reducing production costs have been a widespread concern among scientific and industrial communities. In this study, PSCs are prepared with the simplest device architecture (FTO/MAPbI3 /carbon). A high-quality perovskite film with few interface defects and good carrier transport is obtained by tuning the p-n properties, matching energy levels, and enhancing carrier collection and transport. A PCE of 12.01 % is achieved, which is the best reported to date for this device structure. The device also shows excellent long-term stability, owing to the elimination of charge transport layers and the usage of hydrophobic materials. This study provides a new approach to reduce production costs and simplify production of PSCs.

16.
ACS Appl Mater Interfaces ; 12(40): 44700-44709, 2020 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-32933250

RESUMEN

Lead halide perovskite has in recent years gained widespread interest due to its excellent physical and chemical properties, as well as superior optoelectronic performance. However, some restrictions still preclude full industrialization of the material, in particular toxicity issues and instability as a result to sensitivity to humidity. Lead-free all-inorganic double perovskite materials have thus recently become a focus of research. Herein, a new narrow bandgap lead-free double perovskite solar cell with a high-quality Cs2PtI6 film is proposed. It exhibits an optical bandgap of 1.37 eV, absorption within a wide range of wavelengths, and a high absorption coefficient. Following optimization, the device displays a best power conversion efficiency of 0.72% with an open-circuit voltage of 0.73 V, a short-circuit current of 1.2 mA/cm2, and a fill factor of 0.82. Crucially, it also demonstrates excellent stability when exposed to extreme conditions such as high humidity, high temperature, and UV-light irradiation. Stability tests show that the PSCs can retain almost 80% of the original efficiency over 60 days stored in ambient temperature without any encapsulation, boosting prospects for applications of lead-free perovskite solar cells.

17.
ACS Appl Mater Interfaces ; 12(12): 13931-13940, 2020 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-32119775

RESUMEN

All-inorganic lead halide perovskite solar cells (PSCs) have drawn widespread interest because of its excellent thermal stability compared to its organic-inorganic hybrid counterpart. Poor phase stability caused by moisture, however, has thus far limited their commercial application. Herein, by modifying the interface between the hole-transport layer (HTL) and the perovskite light absorption layer, and by optimizing the HTL for better energy alignment, we controlled the growth of perovskite, reduced carrier recombination, facilitated carrier injection and transport, and improved the PSC's power conversion efficiency (PCE) and moisture stability. When testing using a positive bias scan, we obtained a significant improvement in PCE, 9.49%, which is the champion efficiency of CsPbIBr2-based inverted PSC at present. The stability measurement shows that the passivated CsPbIBr2-based inverted PSCs can retain 86% of its initial efficiency after 1000 h preserved in ambient air with 65% relative humidity. This study paves a new way for enhancing the moisture stability and power conversion efficiency of CsPbIBr2-based PSCs.

18.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 12): m1535, 2009 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-21578577

RESUMEN

The Ag(I) atom in the salt, [Ag(C(4)H(6)N(2))(2)]NO(3)·2H(2)O, shows a nearly linear coordination [N-Ag-N = 178.26 (7)°]. The cation, anion and water mol-ecules are linked by N-H⋯O and O-H⋯O hydrogen bonds into a layer motif extending parallel to (101).

19.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 12): m1543, 2009 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-21578583

RESUMEN

The three-dimensional coordination polymer, [Mn(2)(C(12)H(6)O(4))(2)(C(12)H(6)N(2)O(2))(H(2)O)](n), features a water-coord-inated Mn(II) ion and an N-heterocycle-chelated Mn(II) ion, both in six-coordinate octa-hedral geometries. Of the two rigid dianions, one is bonded to four Mn(II) ions, with each of the O atoms being connected to a different metal ion. The other dianion uses one carboxyl-ate group to chelate to one Mn(II) ion and its other carboxyl-ate group to bind to two Mn(II) ions.

20.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 12): m1544, 2009 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-21578584

RESUMEN

The Pb(II) atom in the polymeric title compound, [Pb(C(8)H(4)O(4))(C(12)H(6)N(2)O(2))](n), is chelated by the N-heterocycle, and adjacent atoms are bridged by rigid terephthalate dianions into a linear chain. The Pb(II) atom is stereochemically active in a ψ-square-pyramidal coordination geometry in which the lone-pair electrons occupy a basal site. When three other weaker Pb⋯O inter-actions are considered, the geometry is a ψ-dodeca-hedron.

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