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1.
Indian J Urol ; 40(2): 127-132, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38725894

RESUMO

Introduction: The prognostic significance of steroid receptors in bladder cancer remains controversial. This study was designed to determine the expression status of androgen receptor (AR), estrogen receptors (ERα and Erß), and its potential role in predicting survival in patients with nonmuscle invasive bladder cancer (NMIBC). Methods: Sixty patients of NMIBC were screened and 57 (41 males and 16 females) were included in our study. The tissue microarray slides were evaluated by pathologists blinded to the clinical information. Association of distribution of steroid receptors with stage, grade, progression, and recurrence was seen. Results: The mean age of the population was 60.9 ± 9.3 years. Pathologically, majority of the patients were Ta (Ta: T1 stage 61.4% vs. 38.6%). Nine (15.8%) of the tumors stained positive for AR while one (1.8%) tumor stained positive for ERα and 36 (63.2%) tumors stained for ERß. A higher proportion of male NMIBC stained positive for AR (19.5% vs. 6.2%, P = 0.420) while ERß positivity was higher in females (58.5% vs. and 75%,P = 0.247). AR-negative tumors showed higher recurrence (20/48%-42%) as compared to AR-positive tumors (2/9%-22%). ERß-positive tumors showed higher recurrence (15/36%-42% vs. 7/21%-33%, P = 0.179). Progression-free survival (PFS) was found to be significantly lower for ERß-negative group (log-rank test P = 0.035). Conclusion: AR and ERß positivity is found in NMIBC patients while ERα shows minimal staining in NMIBC patients. Although it did not reach a statistical significance, a higher proportion of AR-negative and ERß-positive tumors recurred as compared to AR-positive and ERß-negative patients. PFS was significantly lower in ERß-negative group. Further exploratory studies on larger sample sizes are required to validate these findings in NMIBC patients.

2.
J Phys Chem B ; 128(15): 3707-3719, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38572661

RESUMO

Predicting ionic conductivity is crucial for developing efficient electrolytes for energy storage and conversion and other electrochemical applications. An accurate estimate of ionic conductivity requires understanding complex ion-ion and ion-solvent interactions governing the charge transport at the molecular level. Molecular simulations can provide key insights into the spatial and temporal behavior of electrolyte constituents. However, such insights depend on the ability of force fields to describe the underlying phenomena. In this work, molecular dynamics simulations were leveraged to delineate the impact of force field parameters on ionic conductivity predictions of potassium hydroxide (KOH) in ethylene glycol (EG). Four different force fields were used to represent the K+ ion. Diffusion-based Nernst-Einstein and correlation-based Einstein approaches were implemented to estimate the ionic conductivity, and the predicted values were compared with experimental measurements. The physical aspects, including ion-aggregation, charge distribution, cluster correlation, and cluster dynamics, were also examined. A force field was identified that provides reasonably accurate Einstein conductivity values and a physically coherent representation of the electrolyte at the molecular level.

3.
Eur J Hybrid Imaging ; 7(1): 24, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37945775

RESUMO

INTRODUCTION: Prostate-specific antigen (PSA) is a reliable biomarker for identification of prostate cancer, although a biopsy is still the gold standard for detecting prostate cancer. Similar to higher PIRADS lesions on MRI, the maximal standard uptake value (SUV max) on PSMA PET is linked to a higher likelihood of prostate cancer. Can an mpMRI in conjunction with PSMA PET Scan accurately predict prostate cancer and further trigger omission of biopsy similar to other solid organ urological malignancies? METHODS: Ga-68 PSMA PET and mpMRI were performed for each patient who was a part of this retrospective study. The PET-positive lesion's maximum standardized uptake value (SUVmax) was recorded. Prostate biopsies were performed on patients who had PSMA PET avid lesions and a PIRADS score of 4 or 5. Robot-assisted radical prostatectomy (RARP) was afterward performed on patients who had cancer on their prostate biopsy. The prostatectomy specimen's histopathological information was recorded. Cutoff values and correlations between the variables were determined using the ROC curves and Pearson's correlation test. RESULT: On the basis of suspicious DRE findings or elevated PSA, 70 men underwent mpMRI and PET scans. PIRADS 4 patients had a median (IQR) SUVmax of 8.75 (11.95); whereas, PIRADS 5 patients had an SUVmax of 24.5 (22). The mean SUVmax for patients whose biopsies revealed no cancer was 6.25 ± 1.41. With an AUC of 0.876 on the ROC curve, it was found that there was a significant positive correlation between the results of the mpMRI and PET scans and those of the histopathological investigation. A SUVmax ≥ 8.25 on PSMA PET for a PIRADS 4/5 lesion on mpMRI will aid in correctly predicting malignancy, with a sensitivity of 82.8% and specificity of 100%. CONCLUSION: The findings of this study were positive and indicated that patients with a high suspicion of prostate cancer on mpMRI and PSMA PET (PIRADS ≥ 4 and SUVmax ≥ 8.25). This study substantiates the fact that a combination of mpMRI and PSMA PET can accurately predict localized prostate cancer.

4.
Dalton Trans ; 52(44): 16224-16234, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37853758

RESUMO

Bismuthinite (Bi2S3) nanostructures have garnered significant interest due to their appealing photoresponsivity which has positioned them as an attractive choice for energy conversion applications. However, to utilize their full potential, a simple and economically viable method of preparation is highly desirable. Herein, we present the synthesis and characterization including structural elucidation of a new air- and moisture-stable bismuth-pyrimidylthiolate complex. This complex serves as an efficient single-source molecular precursor for the facile preparation of phase-pure Bi2S3 nanostructures. Powder X-ray diffraction (PXRD), Raman spectroscopy, electron dispersive spectroscopy (EDS) and electron microscopy techniques were used to assess the crystal structure, phase purity, elemental composition and morphology of the as-prepared nanostructures. This study also revealed the profound effects of temperature and growth duration on the crystallinity, phase formation and morphology of nanostructures. The optical band gap of the nanostructures was tuned within the range of 1.9-2.3 eV, which is blue shifted with respect to the bulk bandgap and suitable for photovoltaic applications. Liquid junction photo-electrochemical cells fabricated from the as-prepared Bi2S3 nanostructure exhibit efficient photoresponsivity and good photo-stability, which project them as promising candidates for alternative low-cost photon absorber materials.

5.
J Med Phys ; 48(2): 181-188, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37576101

RESUMO

Purpose: Rising cancer incidences, complex treatment techniques, and workflows have all impacted the radiotherapy scheduling process. Intelligent appointment scheduling is needed to help radiotherapy users adapt to new practices. Materials and Methods: We utilized van Herk's safety margin formula to determine the radiotherapy department's treatment scheduling window (TSW). In addition, we examined the influence of in-room imaging on linac occupancy time (LOT). Varian Aria™ software version 15.1 was used to collect retrospective data on LOT, treatment site, intent, techniques, special protocol, and in-room imaging. Results: Treatment scheduling windows varied across treatment sites. The mean TSW using van Herk's formalism was 31.5 min, significantly longer than the current TSW of 15 min (P = 0.036), with the pelvic site having the longest (43.8 min) and the brain site having the shortest (12 min). 28% of patients exceeded the in-practice TSW of 15 min. 46.2% of patients had multiple images per fraction, with the proportion being highest in pelvic patients (33%). Patients treated with palliative intent, intensity-modulated radiotherapy, special protocols (bladder protocol and gating), and multiple in-room images per fraction had significantly higher LOT. High treatment time uncertainty was observed in the pelvic and thorax sites, indicating the impact of in-room imaging frequency and on-couch treatment decisions on overall treatment time and indicating that current treatment practices should be reviewed and modified if necessary. Conclusions: The time margin recipe can customize the treatment scheduling window and improve treatment practices. This formalism can help manage the radiotherapy department's workload and reduce patient wait times.

6.
J Med Phys ; 48(1): 13-18, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37342597

RESUMO

Background and Purpose: In recent years, data science approaches have entered health-care systems such as radiology, pathology, and radiation oncology. In our pilot study, we developed an automated data mining approach to extract data from a treatment planning system (TPS) with high speed, maximum accuracy, and little human interaction. We compared the amount of time required for manual data extraction versus the automated data mining technique. Materials and Methods: A Python programming script was created to extract specified parameters and features pertaining to patients and treatment (a total of 25 features) from TPS. We successfully implemented automation in data mining, utilizing the application programming interface environment provided by the external beam radiation therapy equipment provider for the whole group of patients who were accepted for treatment. Results: This in-house Python-based script extracted selected features for 427 patients in 0.28 ± 0.03 min with 100% accuracy at an astonishing rate of 0.04 s/plan. Comparatively, manual extraction of 25 parameters took an average of 4.5 ± 0.33 min/plan, along with associated transcriptional and transpositional errors and missing data information. This new approach turned out to be 6850 times faster than the conventional approach. Manual feature extraction time increased by a factor of nearly 2.5 if we doubled the number of features extracted, whereas for the Python script, it increased by a factor of just 1.15. Conclusion: We conclude that our in-house developed Python script can extract plan data from TPS at a far higher speed (>6000 times) and with the best possible accuracy compared to manual data extraction.

7.
Int J Biol Macromol ; 233: 123575, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36764347

RESUMO

Polyhydroxybutyrate (PHB) has significant potential for replacing non-biodegradable traditional plastic, which is responsible for several global environmental issues. The main problem with switching to bio-based alternatives for petrochemical plastics is the large price gap on the market. To overcome this problem, the present research was focused on the utilization of inexpensive substrates i.e. agricultural residues for cost-effective PHB production by endospore-forming bacteria Bacillus badius MTCC 13004. For efficient PHB production, Box-Behnken Design (BBD) was selected for media optimization and to observe the interactive effects of four variables i.e. pH, Na acetate, Banana peel, and mustard cake. PHB yield of 2.11 g/L was attained under optimized conditions compared to non-optimized conditions (0.72 g/L). FTIR spectra analysis of PHB extracted from Bacillus badius was found to be similar to commercial PHB. NMR data was also matched with the chemical shift signals CH, CH2, and CH3 of PHB. The melting temperature (Tm) and glass transition temperature (Tg) of PHB from Bacillus badius was found to be 165.14 and 2.68 °C, respectively. Further, PCR protocol was also designed to amplify key enzymes of the PHB synthesis pathway i.e. PHB synthase (phb C gene).


Assuntos
Bacillus , Análise Custo-Benefício , Bacillus/metabolismo , Plásticos/metabolismo , Hidroxibutiratos/química , Poliésteres/química
8.
Dalton Trans ; 51(32): 12181-12191, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35876784

RESUMO

Stibnite Sb2S3 and tetrahedrite Cu12Sb4S13 nanostructures being economical, environmentally benign and having a high absorption coefficient are highly promising materials for energy conversion applications. However, producing these materials especially tetrahedrite in the phase pure form is a challenging task. In this report we present a structurally characterized single source molecular precursor [Sb(4,6-Me2pymS)3] for the facile synthesis of binary Sb2S3 as well as ternary Cu12Sb4S13 in oleylamine (OAm) at a relatively lower temperature. The as-prepared Sb2S3 and Cu12Sb4S13 nanostructures were thoroughly checked for their phase purity, elemental composition and morphology by powder X-ray diffraction (pXRD), electron dispersive spectroscopy (EDS) and electron microscopy techniques. pXRD and EDS studies confirm the formation of phase pure, crystalline orthorhombic Sb2S3 and cubic Cu12Sb4S13. The SEM, TEM and HRTEM images depict the formation of well-defined nanorods and nearly spherical nanocrystals for Sb2S3 and Cu12Sb4S13, respectively. The Sb2S3 nanorods and Cu12Sb4S13 nanocrystals exhibit an optical bandgap of ∼1.88 and 2.07 eV, respectively, which are slightly blue-shifted relative to their bulk bandgap, indicating the quantum confinement effect. Finally, efficient photoresponsivity and good photo-stability were achieved in the as-prepared Sb2S3 and Cu12Sb4S13 nanostructure-based prototype photo-electrochemical cell, which make them promising candidates for alternative low-cost photon absorber materials.

9.
J Cancer Res Ther ; 18(1): 84-88, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35381767

RESUMO

Purpose: Radiation dermatitis is most common and debilitating side effects of radiotherapy leading to treatment interruption, thereby compromising the local control, and effecting quality of life. With the invent of modern imaging and recent advances in megavoltage radiotherapy, radiation-related side effects have reduced. In this audit, we report the risk factors associated with Grade III dermatitis in modern centers. Materials and Methods: We analyzed 172 patients treated with volume modulated arc therapy (VMAT) and static field intensity-modulated radiotherapy (SFIMRT) at our center. All head and neck, breast, gynecological, GU malignancies, and sarcoma patients treated with a dose of >45 Gy from April 2018 to December 2019 were included in the study. On couch, treatment verification was done with cone-beam computer tomography (CBCT). Slice-by-slice verification of planning target volume (PTV) with CBCT was done in the first three fractions and weekly thereafter. Skin evaluation was done using CTCAE v. 5. Statistical analysis was done using SPSS v. 22. Results: Of the 172 patients treated with VMAT and SFIMRT, 15 patients (8.7%) had Grade III dermatitis. Grade III dermatitis was mostly seen in breast cancer followed by head-and-neck patients. More reactions were observed in patients with advanced stage disease. Treatment verification is important at the later course of treatment, especially in head-and-neck cases where the treatment volume is large and PTV may extend outside skin. Contributing factors of radiation dermatitis at modern radiotherapy center are gene mutation, use of concurrent chemoradiotherapy, and bolus. Conclusion: We hereby conclude that PTV mismatch in weekly treatment verification, genetic mutations, concurrent chemo-radiotherapy, use of thermoplastic mask, and bolus are the contributing factors for Grade III dermatitis in modern radiotherapy centers.


Assuntos
Radioterapia (Especialidade) , Radioterapia de Intensidade Modulada , Humanos , Qualidade de Vida , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos
10.
Pol Przegl Chir ; 95(1): 6-12, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36806163

RESUMO

<b>Aim:</b> The course of acute pancreatitis is variable with patients at risk of poor outcomes. The purpose of this study was to compare Modified Glasgow-Imrie, Ranson, and APACHE II scoring systems in predicting the severity of acute pancreatitis. </br></br> <b> Material and Methods: </b> After a brief history, clinical examination and qualifying inclusion criteria, 70 patients (41 women, 29 men) diagnosed with acute pancreatitis were included in the study. The three scores were calculated for each patient and evaluated for their role in the assessment of specific outcomes. </br></br> <b>Results:</b> 34.3% patients were diagnosed with severe acute pancreatitis, while 65.7% patients had mild acute pancreatitis. A strong positive correlation was found between all the prognostic scores and the severity of disease. In the prediction of the severity of disease according to AUC, it was found that Glasgow-Imrie score had an AUC of 0.864 (0.7560.973), followed very closely by APACHE II score with an AUC of 0.863 (0.7580.968). APACHE II had the highest sensitivity (79.17%) in predicting severity while Glasgow-Imrie score was the most specific (97.83%) of all the scores. Patients with a Glasgow-Imrie score above the cut-off value of 3 had more complications and a longer hospital stay. </br></br> <b>Conclusion:</b> The Glasgow-Imrie score was comparable to APACHE II score and better than Ranson score statistically in predicting the severity of acute pancreatitis. Its administration in predicting the severity of acute pancreatitis is recommended.


Assuntos
Pancreatite , Masculino , Humanos , Feminino , APACHE , Doença Aguda , Pancreatite/diagnóstico , Tempo de Internação
11.
Chemosphere ; 287(Pt 3): 132232, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34562706

RESUMO

An attempt was made to understand the sorption behaviour of UO22+, Th4+ and Eu3+ on novel hybrid metal-organic framework composites, FeBDC@CoBDC. The XRD pattern revealed the composite nature of the hybrid MOF materials, while FTIR and Raman spectroscopic analyses evidenced the presence of different functional moieties. The thermal stability of the hybrid MOF composites was investigated through thermogravimetric analysis. The sorption predominantly followed Langmuir isotherm with sorption capacity of 189 mg g-1, 224 mg g-1 and 205 mg g-1 for UO22+, Th4+ and Eu3+ respectively. The sorption proceeded through chemisorption following pseudo 2nd order rate kinetics. The processes were found to be thermodynamically favourable and endothermic in nature. However, they were entropically driven. Multiple contacts of complexing agents were necessary for quantitative elution of f-elements from loaded MOF. The MOF showed moderate stability towards radiation exposure. DFT calculation was used for the optimization of structures, estimation of bond length and estimation of binding energy. In hybrid MOF composites, the Fe atom was having six coordination with 4 O atoms of BDC moieties and 2 O atoms of -OH groups. The O atoms of BDC and -OH groups were coordinated to Eu, Th and U atoms during their sorption.


Assuntos
Estruturas Metalorgânicas , Adsorção , Flúor , Cinética
12.
Urol Ann ; 13(4): 405-411, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34759654

RESUMO

INTRODUCTION: The objective of the study is to evaluate the outcome of robot-assisted laparoscopic repair of injuries to urinary tract following gynecological surgery and obstetric injury. METHODS: This retrospective analysis from prospectively collected data of repair of injuries to bladder and ureter using da Vinci Si robotic platform was carried out. Between April 2014 and May 2019, 27 patients were operated on in a single surgical unit; 25 had hysterectomy and 2 were obstetric cases. Fifteen patients underwent vesicovaginal fistula (VVF) repair, ten underwent ureteral reimplant, with concomitant psoas hitch, and two underwent Boari flap repair following gynecological surgery and obstetric injury. RESULTS: Among 15 patients of VVF repair, 3 cases were previously attempted failed repair, 2 underwent concomitant ureteral reimplant, and 1 underwent concomitant ovarian cystectomy. The mean total operative time was 126 (75-206) min, and the mean hospital stay was 4.4 (3-6) days. Among 12 cases of ureteral injury, 5 were on the right side and 7 were on the left side; the mean total operative time was 150.16 (110-215) min, and the mean hospital stay was 4 (3-7) days. No case required conversion to open in this cohort. All cases were successfully cured without any recurrence of fistula or stricture during their mean follow-up period of 35.3 (9-66) months. CONCLUSIONS: Robot-assisted laparoscopic repair for injuries to bladder and ureter is effective and highly successful even in previously failed cases.

13.
J Nanosci Nanotechnol ; 21(6): 3580-3587, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34739810

RESUMO

The study focused on the medicinal properties of citrus fruits and their ability to synthesize silver nanoparticles. As the resistance against the modern antibiotic agents is on increase, finding new and effective natural antibiotic agents is the need of the modern era. Similarly, bio-synthesis of nanoparticles is also being encouraged for eco-friendly reasons. Due to remarkable medicinal and industrial applications of silver nanoparticles (AgNPs), citrus fruit juice is used to reduce silver ions for the green synthesis of AgNPs. Phytochemical analysis revealed the presence of various constituents which impart antibacterial property to citrus fruits, analyzed against four pathogenic bacteria. Also, citrus fruit juice exhibits radical scavenging activity because of these constituents. Further, the AgNPs synthesized using citrus fruits were characterized using Ultra-Violet Visible (UV-VIS) spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy and Transmission Electron Microscopy (TEM) to study the shape and size of the AgNPs. Anticancer activity of AgNPs was also evaluated against Colo-205 cell lines and found to inhibit 37.9% growth of cell lines at the concentration of 10 µg/ml. Hence, synthesized AgNPs can be used effectively against cancer cell lines in combination with other anti-cancer agents.


Assuntos
Antineoplásicos/farmacologia , Citrus , Nanopartículas Metálicas , Antibacterianos/farmacologia , Linhagem Celular Tumoral , Frutas , Química Verde , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Prata/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
14.
J Cancer Res Ther ; 17(4): 1125-1131, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34528577

RESUMO

CONTEXT: This research describe the characteristic volume expansion of a moving target as a function of differential margins. AIM: We aimed to ascertain the volume change after giving margin for clinical and set up uncertainties including generating internal target volume (ITV) for moving target. MATERIALS AND METHODS: Settings and Design - Spheres of diameter (0.5-10 cm) with differential expansion of 1-15 mm were generated using a mathematical formula. Moving targets of radius 1-5 cm were generated, and the resultant volume envelopes with incremental motion from 1 to 20 mm were obtained. All relative volume change results were fitted with mathematical functions to obtain a generalized mathematical formula. STATISTICAL ANALYSIS USED: None. RESULTS: The percentage increase in volume (%ΔVp) was much more pronounced for smaller radius target. For moving target with relatively smaller radius, %ΔVp is predominant over the absolute volume change and vice versa in case of larger radius. Mathematical formulae were obtained for %ΔVp as a function of radius and expansion and for %ΔVp in ITV volume as a function of radius and tumor movement. CONCLUSIONS: This study provides an idea of volume change for various expansions for various size targets and/or moving target for different range of movements. It establishes a correlation of these volume changes with the changing target size and range of movements. Finally, a clinically useful mathematical formulation on volume expansion has been developed for rapid understanding of the consequence of volume expansion.


Assuntos
Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Modelos Teóricos , Radiocirurgia/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Carga Tumoral , Humanos , Movimento , Respiração , Tomografia Computadorizada por Raios X
15.
Int J Surg Case Rep ; 84: 106109, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34139422

RESUMO

INTRODUCTION: Numerous complications can occur after a surgery, but gossypiboma is undoubtedly the most unwanted and undesirable complication of a procedure for any surgeon with legal implications. Once suspected, the minimally invasive surgical approach should be considered for its management. PRESENTATION OF CASE: An adult P1L1E1 female presented to the surgery OPD with a painless abdominal mass which progressively increased in size in the past 4 months. She underwent emergency surgery for a ruptured ectopic pregnancy 6 months back at some other health centre. On computed tomography scan of the abdomen, a well-defined heterogenous cystic lesion of size 9.8 cm × 9.2 cm × 7 cm was noted intraperitoneally. Few air foci with a hyperdense tubular structure within the lesion were seen, suggestive of a retained surgical sponge with its radio-opaque marker also visualised. The retained sponge was successfully retrieved by the laparoscopic approach. DISCUSSION: Traditionally, the open approach for the removal of the sponge was more accepted compared to the laparoscopic approach. This was due to the belief that intense foreign body reaction and dense adhesions around the sponge may make the laparoscopic approach difficult. However, laparoscopy can prove to be beneficial with its advantages of early ambulation, reduced post-op pain, cosmetically improved results and shorter length of hospital stay. CONCLUSION: All precautions must be taken to avoid retention of surgical sponge post-surgery. Case reports in which laparoscopy is used to retrieve gossypiboma are rare. The authors recommend the use of laparoscopy as a therapeutic option in the event of such mishaps.

16.
Chemosphere ; 277: 130324, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33789218

RESUMO

The emerging contaminants in wastewater discharged from numerous chemical process industries, pharmaceutical industries, textile, and wineries have attracted the attention of the scientific community due to their toxicity and persistence in the environment. The conventional techniques are incompetent to treat many of such recalcitrant toxic pollutants. To achieve high mineralization, advanced oxidation processes (AOPs) are found to be more efficient for the degradation of these organic pollutants without producing secondary pollutants with no/less amount of sludge. The primary oxidation agents for AOPs are in-situ generated free radicals, which are highly reactive and effective oxidants for degrading any type of organic molecules present in the wastewater. In the past decades, the combination of AOPs or simultaneous application of more than one AOP has been investigated extensively for wastewater treatment and these hybrid-AOPs have been reported to be beneficial for high-level mineralization of organic pollutants. This paper presented the characteristics, properties and influence of parameters in sono-photo-ferrioxalate system. The primary operating parameters in sono-photo-ferrioxalate system that affect the kinetics are defined as the solution pH, temperature, molar ratio of Fe3+/C2O42-, H2O2 concentration, source of light, ultrasound intensity, dissolved gases, and size of cavitation bubble. In this process, several oxidizing radicals are generated such as HO•, HO2•, C2O4•-, CO2•- and O2•- which are also responsible for degradation. In this review, we have mainly addressed the degradation of recalcitrant pollutants using the sono-photo-ferrioxalate system and a critical analysis of process parameters that influence mineralization efficiency.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Peróxido de Hidrogênio , Oxalatos , Oxirredução , Águas Residuárias , Poluentes Químicos da Água/análise
17.
Environ Sci Pollut Res Int ; 28(6): 7332-7346, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33025446

RESUMO

The main objective of the present work was to understand the interactive behaviour of various operating parameters including concentration of pollutants during binary electrochemical mineralization of the two nitrogenous heterocyclic pollutants in the aqueous solution. Indole and pyrrole were selected as pollutants, whereas Pt/Ti was selected as anode and cathode. The effects of different operating parameters like current density, solution conductivity, initial concentration of the pollutants and time were studied. Taguchi method was used to optimize these operating parameters for obtaining the ultimate rate of degradation for the nitrogenous compounds. There were basically two responses, i.e. chemical oxygen demand (COD) degradation and specific energy consumption. These responses were maximized and minimized, respectively. At the optimum condition, removal efficiencies of pyrrole, indole and COD were found to be 46.1%, 62.4% and 61.4%, respectively. The optimum value of specific energy consumption was found to be 159.5 kWh per kg COD removed. Possible mineralization pathways are also proposed on the basis of the identified intermediates by gas chromatography coupled with mass spectroscopy. The operating cost was also calculated for the binary lab-scale treatment of the indole and pyrrole and compared with reported cost analysis for the electrochemical treatment.


Assuntos
Nitrogênio , Poluentes Químicos da Água , Análise da Demanda Biológica de Oxigênio , Técnicas Eletroquímicas , Eletrodos , Oxirredução , Poluentes Químicos da Água/análise
18.
Urology ; 144: 234-240, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32621822

RESUMO

OBJECTIVE: To demonstrate the surgical technique of dual kidney transplantation in ipsilateral iliac fossa using da Vinci Si robotic platform METHODS: Dual kidneys from expanded criteria deceased donor were used in single recipients using robotic platform in 6 recipients. Following bench surgery, both kidneys were again placed into preservation fluid and ice-box. Robot was docked between 2 legs of the recipient. Common iliac and external iliac vessels on right side were dissected using robotic instruments. A 7 cm pfannenstiel incision was placed and one kidney was dropped into the abdomen; external aponeurosis was closed to restore the pneumoperitoneum. First kidney vascular anastomosis was done with common iliac vessels. Second kidney was introduced through the same wound and transplanted with external iliac vessels. Both ureters were implanted separately into the bladder. RESULTS: Between January 2013 and December 2017, 6 patients had dual robotic-assisted laparoscopic kidney transplantation. All procedures were carried out successfully without conversion to open operation. Mean time for venous anastomosis, arterial anastomosis and total operation were 16.4 (10-19) minutes, 17.5 (13-24) minutes, and 359.1 (265-500) minutes. Mean blood loss was 188.3 (80-300) ml. Two patients had delayed graft function. One patient expired 3 months following transplant due to pneumonia. CONCLUSION: Using 7 cm Pfannenstiel incision, dual robotic-assisted laparoscopic kidney transplantation with common iliac and external iliac vessels is technically feasible.


Assuntos
Artéria Ilíaca/cirurgia , Veia Ilíaca/cirurgia , Transplante de Rim/métodos , Procedimentos Cirúrgicos Robóticos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
J Environ Manage ; 258: 110032, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31929067

RESUMO

This study focuses on the photocatalytic degradation of quinoline, a recalcitrant heterocyclic nitrogenous aromatic organic compound, using the mixed oxide ZnO-TiO2 photo-catalyst. Photo-catalysts were synthesized by the solid-state reaction method at different calcination temperatures of 400 °C, 600 °C, and 800 °C. Different analytical methods, including Field emission scanning electron microscope, Brunauer-Emmett-Teller surface area, X-ray diffraction, UV-vis diffuse reflectance spectroscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy analysis were used for the catalyst characterization. The highest pore surface area of 57.9 m2g-1 was obtained for the photo-catalyst calcined at 400 °C. The effects of calcination temperature, solution pH, initial concentration, catalyst dose as well as irradiation time were studied. At the optimum condition, i.e., calcination temperature of 400 °C, pH ≈8 and catalyst dose of 2.5 gL-1, maximum quinoline degradation and total organic carbon (TOC) removal efficiency of ≈92% and ≈78% were obtained after 240 min for initial quinoline amount of 50 mgL-1. The 1st, 2nd, and nth-order kinetic models were applied to analyze the quinoline degradation rate. The photocatalytic mechanism was studied by drawing energy level diagram with the help of the band-gap structures of the ZnO and TiO2, potential of the free radicals like OH and O2 and HOMO-LUMO energy gap of the quinoline molecule. The proposed pathways of quinoline mineralization were suggested on the basis of the identified intermediates by the gas chromatograph-mass spectrometer analysis and scavenger study.


Assuntos
Quinolinas , Óxido de Zinco , Catálise , Óxidos , Titânio , Difração de Raios X
20.
Photochem Photobiol Sci ; 18(6): 1540-1555, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31020956

RESUMO

In this study, Cu doped ZnO photo-catalysts were used for the degradation of the heterocyclic compounds, pyridine and quinoline. Three ZnO based photo-catalysts with different amounts of Cu doping (1%, 5% and 10%) were synthesized by precipitation method. The characterization of the catalyst was done using field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Brunauer Emmett Teller (BET), diffuse reflectance spectroscopy (DRS) and photo-luminescence (PL) techniques. The band gaps of the pure ZnO, and 1%, 5% and 10% Cu doped ZnO photo-catalysts were found to be 3.27 eV, 3.21 eV, 3.17 eV and 2.91 eV, respectively. The effects of pH, photo-catalyst dose and irradiation time were studied. Under optimum conditions (5% Cu doped ZnO, dose of 1.2 g L-1 for pyridine and 1.6 g L-1 for quinoline, pH = 11 and time = 5 h), the maximum pyridine and quinoline mineralization efficiencies were found to be 92.4% and 74.3%, respectively. The mineralization process followed first-order kinetics. The in situ formation of singlet oxygen, hydroxyl radicals and superoxide radicals was confirmed by reactive oxygen species (ROS) scavenger studies. Catalyst reusability studies showed excellent mineralization up to four consecutive cycles. The enhanced photo-catalytic mechanism was studied by comparing the band structure with respect to the potential of highly reactive species (˙OH and O2˙-). A possible mineralization pathway was proposed on the basis of the intermediates detected by gas chromatography coupled with mass spectrometry (GC-MS) analysis.

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