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Non-native structures (NNS) differ in discrete translational symmetry from the bulk ground state native structure (NS). To explore the extent of deconvolution of various factors relevant to the stabilization of the wurtzite/NNS of MnSe via a heat-up method, we performed experiments using various ligands (oleic acid, oleylamine, octadecylamine, stearic acid, and octadecene), solvents (tetraethylene glycol and octadecene), and precursor salts (manganese chloride and manganese acetate). Experiments suggest that oleic acid in the presence of tetraethylene glycol and oleylamine in the presence of octadecene stabilize wurtzite/NNS. Further, density functional theory (DFT) computations explore the interaction between the functional groups in ligands and the most exposed surfaces of wurtzite/NNS and rocksalt/NS polymorphs. Computations suggest that the interactions between relevant surface facets with carboxylic acid and the double bond functional groups suppress the phase transformation from NNS to NS. In addition, the ionizability of the precursor salt also determines the rate of formation of the metal-ligand complex and the rate of nucleation. Consequently, the formation rate of the Mn-ligand complex is expected to be greater in the case of chloride salt than acetate salt because the chloride salt has higher ionizability in ethylene glycol. From the above, we conclude that the kinetics of the wurtzite/NNS to rocksalt/NS phase transformation depends mainly on two factors: (1) nucleation/growth kinetics which is controlled by the ionizability of the precursor salt, solvent, and stability of the metal-ligand complex, and (2) the activation energy barrier of the NNS to NS conversion which is controlled by surface energy minimization with the ligand.
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This study addresses the urgent issue of water pollution caused by iron (Fe) and manganese (Mn) ions. It introduces an innovative approach using graphene oxide (GO) and GO-decorated polyethersulphone (PES) membranes to efficiently remove these ions from contaminated water. The process involves integrating GO into PES membranes to enhance their adsorption capacity. Characterization techniques, including scanning electron microscopy, Fourier-transform infrared, and contact angle measurements, were used to assess structural and surface properties. The modified membranes demonstrated significantly improved adsorption compared to pristine PES. Notably, they achieved over 94% removal of Mn2+ and 93.6% of Fe2+ in the first filtration cycle for water with an initial concentration of 100 ppm. Continuous filtration for up to five cycles maintained removal rates above 60%. This research advances water purification materials, offering a promising solution for heavy metal ion removal. GO-decorated PES membranes may find application in large-scale water treatment, addressing environmental and public health concerns.
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Grafite , Ferro , Manganês , Membranas Artificiais , Polímeros , Sulfonas , Poluentes Químicos da Água , Purificação da Água , Grafite/química , Polímeros/química , Manganês/química , Ferro/química , Purificação da Água/métodos , Adsorção , Sulfonas/química , Filtração/métodosRESUMO
Self-powered photodetectors have grown as inevitable members of the optoelectronic device family. However, it is still challenging to achieve self-powered photodetection with good responsivity in the visible spectrum region. Herein, we report solution-processable poly(3-hexylthiophene) (P3HT)-molybdenum disulfide (MoS2) organic-inorganic hybrid material, which can be used as the active layer in self-powered photodetectors. The morphological and structural properties of the synthesized P3HT-MoS2hybrid material has been discussed using atomic force microscopy and transmission electron microscopy, respectively. The hybrid material loaded with 1 wt% MoS2has shown an enhancement in the self-assembly of polymer in the form of fibrillar formation and excellent structural features in terms ofπ-conjugation. The self-powered photodetectors have been fabricated in indium tin oxide (ITO) coated glass/P3HT-MoS2/Al configuration. The merit of P3HT-MoS2hybrid photodetectors is measured under the illumination of 470, 530, and 627 nm light in ambient conditions. P3HT-MoS2photodetectors show significantly higher responsivity and detectivity. The photo responsivity and detectivity in P3HT-MoS2devices are found to be 271.2 mA W-1and 4.4 × 1010jones at zero bias, respectively, for 470 nm light with the optical power density of 74.1µW cm-2. Furthermore, the photocurrent switching behaviour at periodic illuminations of 1 Hz has also been examined for P3HT-MoS2self-powered photodetectors.
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OBJECTIVES: To assess the transfer accuracy of three-dimensional (3D) printed transfer trays and compare them with transfer trays made up of polyvinyl siloxane (PVS) for use in indirect bonding. DESIGN: This was a two-arm parallel prospective randomised controlled trial. SETTING: The trial was undertaken at the outpatient department of a dental college. PARTICIPANTS: A total of 30 patients (18 men, 12 women) were randomly allocated to two groups. METHODS: The inclusion criteria included patients with permanent and fully erupted dentition (age range = 17-24 years), Angles class I malocclusion with crowding <3 mm requiring non-extraction treatment, good oral hygiene and no previous history of orthodontic treatment. Blinding was applicable only for outcome assessment. Indirect bonding was performed by the primary investigator for both the groups. Digital images of the pre-transfer and post-transfer brackets were obtained by means of an intra-oral scanner and compared using software. Superimpositions of pre- and post-transfer images were done to determine the transfer error for linear and angular variables for all tooth types. RESULTS: A total of 600 teeth were bonded, 300 each for both groups. Statistically significant differences were observed in all dimension between the two groups, with 3D-printed trays being more accurate than PVS trays except in the vertical dimension (P < 0.05). The prevalence of clinically unacceptable transfer errors revealed that most of the transfer errors were in the vertical dimensions for 3D-printed trays. CONCLUSION: 3D-printed trays are more accurate than PVS trays except for transfers in vertical dimension.
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Colagem Dentária , Má Oclusão Classe I de Angle , Braquetes Ortodônticos , Adolescente , Adulto , Feminino , Humanos , Masculino , Modelos Dentários , Estudos Prospectivos , Adulto JovemRESUMO
Platelet-rich fibrin (PRF) is a biocompatible fibrin matrix that acts as a resorbable membrane, collecting platelet cytokines, growth factors, and cells and releasing them. It is easily extracted from blood. Many dentists use PRF, a concentrated growth factor solution, to treat various lesions and regenerate tooth and oral tissues. This research examines the pros, cons, and suggestions of using PRF in dentistry.
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Paper-based sensors, often referred to as paper-based analytical devices (PADs), stand as a transformative technology in the field of analytical chemistry. They offer an affordable, versatile, and accessible solution for diverse analyte detection. These sensors harness the unique properties of paper substrates to provide a cost-effective and adaptable platform for rapid analyte detection, spanning chemical species, biomolecules, and pathogens. This review highlights the key attributes that make paper-based sensors an attractive choice for analyte detection. PADs demonstrate their versatility by accommodating a wide range of analytes, from ions and gases to proteins, nucleic acids, and more, with customizable designs for specific applications. Their user-friendly operation and minimal infrastructure requirements suit point-of-care diagnostics, environmental monitoring, food safety, and more. This review also explores various fabrication methods such as inkjet printing, wax printing, screen printing, dip coating, and photolithography. Incorporating nanomaterials and biorecognition elements promises even more sophisticated and sensitive applications.
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Técnicas Biossensoriais , Papel , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Humanos , Desenho de Equipamento , Monitoramento Ambiental/métodos , Monitoramento Ambiental/instrumentação , Ácidos Nucleicos/análise , Proteínas/análise , Nanoestruturas/químicaRESUMO
Objective: Most radiotherapy patients with prostate cancer are treated with volumetric modulated arc therapy (VMAT). Advantages of VMAT may be limited by daily treatment uncertainties such as setup errors, internal organ motion, and deformation. The position and shape of prostate target as well as normal organ, i.e., rectum volume around the target, may change during the course of treatment. The aim of the present work is to estimate rectal toxicity estimation using a novel two-level biological knowledge-based fuzzy logic method. Both prostate and rectal internal motions as well as setup uncertainties are considered without compromising target dose distribution in the present study. Materials and Methods: The Mamdani-type fuzzy logic framework was considered in two levels. The prostate target volume changes from minimum to maximum during the course of treatment. In the first level, the fuzzy logic was applied for determining biological acceptable target margin using tumor control probability and normal tissue complication probability (NTCP) parameters based on prostate target motion limits, and then, fuzzy margin was derived. The output margin of first-level fuzzy logic was compared to currently used margins. In second-level fuzzy, rectal volume variation with weekly analysis of cone-beam computed tomography (CBCT) was considered. The biological parameter (NTCP) was calculated corresponding to rectal subvolume variation with weekly CBCT image analysis. Using irradiated volume versus organ risk relationship from treatment planning, the overlapped risk volumes were estimated. Fuzzy rules and membership function were used based on setup errors, asymmetrical nature of organ motion, and limitations of normal tissue toxicity in Mamdani-type Fuzzy Inference System. Results: For total displacement, standard errors of prostate ranging from 0 to 5 mm range were considered in the present study. In the first level, fuzzy planning target volume (PTV) margin was found to be similar or up to 0.5 mm bigger than the conventional margin, but taking the modeling uncertainty into account resulted in a good match between the calculated fuzzy PTV margin and conventional margin formulations under error 0-5 mm standard deviation (SD) range. With application of fuzzy margin obtained from first-level fuzzy, overlapped rectal volumes and corresponding NTCP values were fuzzified in second-level fuzzy using rectal volume variations. The final risk factor (RF) of rectum was qualitatively assessed and found clinically acceptable for each fractional volume of irradiated to total volume and relevant NTCP values. The reason may be at 5 mm SD displacement error range, NTCP values would be within acceptable limit without compromising the tumor dose distribution though the confounding factors such as organ motion, deformation of rectum, and in-house image matching protocols exist. Conclusion: A new approach of two-level fuzzy logic may be suitable to estimate possible organ-at-risk (OAR) toxicity biologically without compromising tumor volume that includes both prostate target and OAR rectum deformation even at displacement standard errors of prostate ranging from 0 to 5 mm range which was considered in the present study. Using proposed simple and fast method, there is an interplay between volume-risk relationship and NTCP of OARs to judge real-time normal organ risk level or alter the treatment margins, particularly concern to individual factors such as comorbidities, genetic predisposition, and other lifestyle choices even at high displacement errors >5 mm SD range.
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It is a crucial challenge to obtain the desired electronic properties of two-dimensional materials for various ubiquitous applications and improvements in the existing technology. In this article, we have demonstrated the modulation in electronic features of the chemical vapor deposition (CVD) grown single-layer graphene (SLG) via wet doping of poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). The PEDOT:PSS is well known as conducting polymer and used as transparent conducting electrode in flexible organic electronic devices. The effect of doping on SLG samples were examined by Raman spectroscopy, electrical transport measurement, atomic force microscopy (AFM), and Kelvin probe force microscopy (KPFM). The Raman peaks position of doped samples provided sought evidence of p-type doping of SLG after the deposition of PEDOT:PSS films. The electrical measurement confirmed the p-type doping of SLG and also revealed enhanced carrier density and mobility of SLG after the deposition of PEDOT:PSS films. AFM micrographs revealed the homogeneous loading of PEDOT:PSS particles over the SLGs. Further, KPFM technique was used to estimate the work function modulation of SLG after PEDOT:PSS film deposition. Our investigation will be useful for understanding the device physics as well as improvement of photovoltaic devices based on PEDOT:PSS coated graphene.
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PURPOSE: The purpose of present study is to estimate asymmetric margins of prostate target volume based on biological limitations with help of knowledge based fuzzy logic considering the effect of organ motion and setup errors. MATERIALS AND METHODS: A novel application of fuzzy logic modelling technique considering radiotherapy uncertainties including setup, delineation and organ motion was used in this study to derive margins. The new margin was applied in prostate cancer treatment planning and the results compared very well to current techniques Here volumetric modulated arc therapy treatment plans using stepped increments of asymmetric margins of planning target volume (PTV) were performed to calculate the changes in prostate radiobiological indices and results were used to formulate the rule based and membership function for Mamdani-type fuzzy inference system. The optimum fuzzy rules derived from input data, the clinical goals and knowledge-based conditions imposed on the margin limits. The PTV margin obtained using the fuzzy model was compared to the commonly used margin recipe. RESULTS: For total displacement standard errors ranging from 0 to 5 mm the fuzzy PTV margin was found to be up to 0.5 mm bigger than the vanHerk derived margin, however taking the modelling uncertainty into account results in a good match between the PTV margin calculated using our model and the one based on van Herk et al. formulation for equivalent errors of up to 5 mm standard deviation (s. d.) at this range. When the total displacement standard errors exceed 5 mm s. d., the fuzzy margin remained smaller than the van Herk margin. CONCLUSION: The advantage of using knowledge based fuzzy logic is that a practical limitation on the margin size is included in the model for limiting the dose received by the critical organs. It uses both physical and radiobiological data to optimize the required margin as per clinical requirement in real time or adaptive planning, which is an improvement on most margin models which mainly rely on physical data only.
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AIM: The aim is to study the assessment of feasibility of medial sural artery perforator (MSAP) free flap for head and neck reconstruction at our center. MATERIALS AND METHODS: Oral cancer patients with squamous cell carcinoma of the tongue, buccal mucosa, and floor of mouth cancer attending our center were reconstructed using MSAP flap after oncologic resection. Handheld 8 MHz Doppler was used to identify the perforator preoperatively. RESULTS: We reconstructed 10 patients using MSAP flap. The flap was designed according to defect and donor site was primarily closed in all cases. Excellent results were seen in nine patients reconstructed with MSAP flap without any postoperative complication. Flap failure occurred in one patient due to venous thrombosis. The thickness of flap ranged from 4 to 8 mm. The vascular pedicle length ranged from 9 to 13 cm. CONCLUSION: The MSAP flap is appropriate for medium-sized oral defect reconstruction, with a long pedicle of matching caliber, adequate tissue volume, and minimal donor-site morbidity which makes it comparable to other microvascular free flaps such as radial artery free flap (RAFF) and anterolateral thigh flap.
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The aim of this paper is to study the outcome of single-layer end to side dunking pancreatojejunostomy technique in 32 patients of malignant pancreatic disease undergoing Whipple's surgery in a tertiary care oncology centre in India. From January 2013 to January 2016, 32 consecutive patients who underwent pancreatoduodenectomy for malignant diseases were analysed retrospectively. All the patients underwent standard Whipple's operation. Pancreatojejunostomy was established in a single-layer end to side dunking manner with PDS 4-0. Various patient data, i.e. preoperative symptoms and demography, intra-operative time, blood loss and need of blood transfusion, postoperative hospital stay and complications, were noted. Mean operative time was 3.5 h approximately. Mean blood loss was 328 ml approx (range 150-600 ml). Postoperative delayed gastric emptying was observed in 8 (25%) patients. Three (9.4%) patients developed superficial surgical site infection. Mean hospital stay was 16.5 days (range 13-20 days). There were no pancreatic leak or fistula and no perioperative mortality. It is a feasible technique. It achieved zero leak rates, zero mortality and minimal morbidity without compromising any oncologic principles.
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Synovial sarcoma is the uncommon malignant tumor of children and adolescents. It usually involves the soft tissues of the upper and lower joints and most commonly affects adults in their fourth decade of life. We report a rare case of synovial sarcoma of the head and neck region in a five-year-old child who has presented with right side cervical lymphadenopathy associated with dysphagia and hoarseness of voice. Patient was managed by modified radical neck dissection followed by chemotherapy.