One-pot hydrothermal preparation and defect-enhanced photocatalytic activity of Bi-doped CdWO4 nanostructures.

In the field of photocatalysis, the suppression of electron-hole recombination through various defects has been an emerging trend to enhance photocatalytic activity. The separation efficiency of electron-hole recombination of well-explored wolframite structured monoclinic CdWO4, prepared using the one-pot hydrothermal method, was further improved by Bi3+ doping in CdWO4. Studies using the partial density of states illustrated that Bi 6s and 6p orbitals altered the electronic band structure to the extent of lowering the band gap, resulting in more photon absorption. The positron annihilation lifetime studies unveiled the formation of cluster defects such as oxygen (V0o, Vo1+, Vo2+) along with cadmium vacancies () in Bi-doped CdWO4. The coexistence and synergy of more adsorption sites of V0o, Vo1+, Vo2+, VCd for dye and O2 molecules, suitable oxide/redox band potentials, the modified electronic band structure especially owing to W-O1-Bi-O2-W linkages, together with high surface area endowed Bi-doped CdWO4 to form ˙O2- radicals played a predominant role in the methyl orange degradation. All the experimental findings demonstrated conclusively that Bi3+ doping at Cd2+ facilitated CdWO4 to exhibit superior photocatalytic activity.

A Feasibility Study of Stereotactic Radiosurgery/Stereotactic body Radiotherapy/Stereotactic Ablative Radiotherapy Practice using TomoEDGE in Helical TomoTherapy for Lung, Liver, and Spine Targets.

The primary purpose of the study is to evaluate the implementation of Helical TomoTherapy (HT) for eligible stereotactic radiosurgery/stereotactic body radiotherapy/stereotactic ablative radiotherapy (SRS/SBRT/SABR) cases using TomoEDGE option. The study focuses on reduction of treatment time without compromise in plan quality using TomoEDGE. It is a mode in HT that uses a dynamic opening of the jaws during treatment delivery to reduce the dose penumbra which otherwise is not possible with fixed jaws option. Eligible SRS/SBRT/SABR cases of lung, liver, and spine were used in this study. All planning parameters such as dose prescription to target and critical organs, pitch, and modulation factor were same in all the plans of the same patient with modifications in the field width and jaw mode. First set of plans with 2.5 cm width and second set of plans with 5 cm width were done in dynamic TomoEDGE mode. Third set of plans created with 5 cm width fixed jaw mode and fourth set of plans with 2.5 cm fixed jaw mode for comparison purpose were done. Our observations achieved that a significant milestone with reduction of up to 34.3% in treatment time of liver cases, 35.2% in lung cases, and 28.7% in spine cases was observed using dynamic TomoEDGE mode with 5 cm width, while no significant variation in the planning results compared with plans using 2.5 cm dynamic TomoEDGE option. TomoEDGE is an efficient and useful mode in TomoTherapy to reduce the treatment time with bigger field width in SRS/SBRT/SABR cases without significant changes in the plan quality.

Diagnosis of pseudomyogenic hemangioendothelioma of scapula on limited biopsy: A rare and challenging entity.

Pseudomyogenic hemangioendothelioma (PHE) is a soft-tissue tumor of intermediate malignant potential, recognized as a separate entity in the WHO (World Health Organization) classification of tumors of soft tissue and bone, in 2013. This is a case report of a 33-year-old man with intraosseous scapular PHE reported on small biopsy and immunohistochemistry. The patient presented with local recurrence and metastases even after wide local excision and adjuvant radiotherapy after 14 months. The rarity of this lesion at this site and morphologic clues to diagnosis are important for optimizing the treatment protocol.

In Situ FTIR Spectroscopic Monitoring of the Formation of the Arene Diazonium Salts and its Applications to the Heck-Matsuda Reaction.

This study depicts the use of a fiber-optic coupled Fourier transform infrared spectroscopy-attenuated total reflection (FTIR-ATR) probe for the in-depth study of arene diazonium salt formation and their utilization in the Heck-Matsuda reaction. The combination of these chemical reactions and in situ IR spectroscopy enabled us to recognize the optimum parameters for arene diazonium salt formation and to track the concentrations of reactants, products and intermediates under actual reaction conditions without time consuming HPLC analysis and the necessity of collecting the sample amid the reaction. Overall advantages of the proposed methodology include precise reaction times as well as identification of keto enol tautomerization in allylic alcohols supporting the 'path a' elimination mechanism in the Heck-Matsuda reaction.

Evaluation and Validation of IBA I'MatriXX Array for Patient-Specific Quality Assurance of TomoTherapy®.

TomoTherapy® is a modern radiation treatment technique in which intensity-modulated radiation therapy (IMRT) is delivered in helical fashion. A two-dimensional (2D) array which has been existing for IMRT patient-specific quality assurance (PSQA) verifications for many years is I'MatriXX. Our objectives were to validate this I'MatriXX and to evaluate it for different patient sites and fractionation schedules of TomoTherapy treatment. Twenty-five plans were created with virtual target for different possible pitch values and field widths for validation. Gamma index criteria of 3%/2% dose differences and 3/2 mm distance to agreement were used. QA plans of 26 different treatment sites and different fractionation schedules were used. Results indicated that the matrix response is independent of field width, pitch, and modulation factor of TomoTherapy with 3%, 3 mm criteria. High passing rate ranging from 99.7% to 90.7% was observed for selected patient plans. We found that I'MatriXX 2D array can be utilized for easy and quick TomoTherapy PSQA.

A comparative study of two reconstructive methods and different recommendations in intracavitary brachytherapy.

PURPOSE: Intracavitary brachytherapy (ICB) is a widely used technique in the treatment of cervical cancer. In our Institute, we use different reconstructive methods in the conventional planning procedure. The main aim of this study was to compare these methods using critical organ doses obtained in various treatment plans. There is a small difference in the recommendations in selecting bladder dose point between ICRU (International Commission on Radiation Units & Measurements) -38 and ABS (American Brachytherapy Society). The second objective of the study was to find the difference in bladder dose using both recommendations. MATERIAL AND METHODS: We have selected two methods: variable angle method (M1) and orthogonal method (M2). Two orthogonal sets of radiographs were taken into consideration using conventional simulator. All four radiographs were used in M1 and only two radiographs were used in M2. Bladder and rectum doses were calculated using ICRU-38 recommendations. For maximum bladder dose reference point as per the ABS recommendation, 4 to 5 reference points were marked on Foley's balloon. RESULTS: 64% of plans were showing more bladder dose and 50% of plans presented more rectum dose in M1 compared to M2. Many of the plans reviled maximum bladder dose point, other than ICRU-38 bladder point in both methods. Variation was exceeded in 5% of considerable number of plans. CONCLUSIONS: We observed a difference in critical organ dose between two studied methods. There is an advantage of using variable angle reconstruction method in identifying the catheters. It is useful to follow ABS recommendation to find maximum bladder dose.

Magnitude of shift of tumor position as a function of moderated deep inspiration breath-hold: An analysis of pooled data of lung patients with active breath control in image-guided radiotherapy.

The purpose of this study was to evaluate the reproducibility and magnitude of shift of tumor position by using active breathing control and iView-GT for patients with lung cancer with moderate deep-inspiration breath-hold (mDIBH) technique. Eight patients with 10 lung tumors were studied. CT scans were performed in the breath-holding phase. Moderate deep-inspiration breath-hold under spirometer-based monitoring system was used. Few important bony anatomic details were delineated by the radiation oncologist. To evaluate the interbreath-hold reproducibility of the tumor position, we compared the digital reconstruction radiographs (DRRs) from planning system with the DRRs from the iView-GT in the machine room. We measured the shift in x, y, and z directions. The reproducibility was defined as the difference between the bony landmarks from the DRR of the planning system and those from the DRR of the iView-GT. The maximum shift of the tumor position was 3.2 mm, 3.0 mm, and 2.9 mm in the longitudinal, lateral, and vertical directions. In conclusion, the moderated deep-inspiration breath-hold method using a spirometer is feasible, with relatively good reproducibility of the tumor position for image-guided radiotherapy in lung cancers.