Primary Radical Research Articles

Lenvatinib in combination with PD-1 inhibitor and hepatic arterial infusion chemotherapy (HAIC) for patients with potentially resectable hepatocellular carcinoma: A retrospective analysis.

e16160 Background: Surgical resection is the primary radical treatment for hepatocellular carcinoma (HCC). However, the percentage of initially resectable HCC is only 15-30%, and most patients are unable to undergo surgical resection at the time of initial diagnosis. Lenvatinib combined with PD-1 inhibitor and transarterial intervention has demonstrated good efficacy and safety in unresectable HCC. The retrospective study was designed to explore the safety and conversion effects of lenvatinib + camrelizumab+ HAIC in potentially resectable HCC. Methods: In this single-arm retrospective study, investigators collected patients with potentially resectable HCC treated with lenvatinib + camrelizumab + HAIC from November 2020 to December 2022. The potentially resectable population was selected by the following screening criteria: acceptable liver function (Child-Pugh A-B), good ECOG PS (0-1), intrahepatic tumors confined to one lobe (left, right, or middle lobe), and unresectable by surgical or oncological causes. Results: A total of 64 patients with potentially resectable HCC were included in this analysis. The conversion rate was 31.25% (20), and 23.4% (15) patients underwent surgery. The ORR and DCR were 56.3% and 85.9% by RECIST 1.1. Progression had occurred in 8 patients by the data cutoff on November 1, 2022. The median follow-up time was 13.6 months (range: 2.9-23.7) and 8 patients died. The data was not yet mature, with 1-year survival rate of 90.7%, Overall, 65.6% of patients experienced at least one treatment emergent adverse event (TEAE) and 15.6% of patients had Grade 3/4 TEAE, the most common was hand and foot syndrome (7.8%, n=5). Conclusions: Lenvatinib combined with PD-1 inhibitor and HAIC was well tolerated and showed potential conversion efficacy in the treatment of patients with potentially resectable HCC.

Mechanistic insights into surfactant in enhanced reductive degradation of perchlorinated organic contaminants in Fenton system

This study investigates the mechanisms of surfactants in surfactant-in situ chemical oxidation (S-ISCO) for enhanced degradation of perchlorinated organic contaminants. The addition of Tween-80 (TW-80) or sodium dodecyl sulfate (SDS) in Fenton system resulted in a significant improvement in carbon tetrachloride (CT) removal from 6.2 % to 97.2 % and from 8.2 % to 91.8 %, respectively. Upon further analysis of free radical quenching studies and electron paramagnetic resonance (EPR) tests, it was observed that surfactant radicals were responsible for CT removal with TW-80 presence, while superoxide radicals (O2−•) and carbon dioxide radicals (CO2−•) were the primary radicals with SDS presence. The dechlorination of CT reached 82.1 % and 75.3 % with TW-80 or SDS presence, respectively, indicating that most of the degraded CT could be completely mineralized. The possible degradation pathways of CT were proposed based on the detected intermediates. Additionally, degradation of various single or mixed chlorinated hydrocarbon contaminants with TW-80 or SDS presence in Fenton system was performed. The study also assessed the influence of different solution matrixes on CT degradation and the impact of the recovered surfactant solution after reaction on CT solubilization and removal. In summary, this study provides theoretical support for groundwater remediation with perchlorinated contaminants when containing surfactants.

BF2‐Chelates of N‐Acylhydrazones as Versatile Coupling Partners in Photoredox Promoted Reactions

AbstractFive‐membered difluoroboryl chelate complexes are competent substrates for radical reactions with various radical precursors including potassium trifluoroborates, bis(catecholato)siliconates, 4‐alkyl‐substituted Hantzsch esters, dihydroquinazolinones, esters of N‐hydroxyphthalimide, Katritzky salts, alkyl iodides and thiols. Using these reagents, primary, secondary, and tertiary radicals can be generated under oxidative or reductive conditions and add at the C=N bond of the difluoroboryl chelates leading to hydrazide products.

Photoredox Cleavage of a Csp3-Csp3 Bond in Aromatic Hydrocarbons.

Functionalizing molecules through the selective cleavage of carbon-carbon bonds is an attractive approach in synthetic chemistry. Despite recent advances in both transition-metal catalysis and radical chemistry, the selective cleavage of inert Csp3-Csp3 bonds in hydrocarbon feedstocks remains challenging. Examples reported in the literature typically involve substrates containing redox functional groups or highly strained molecules. In this article, we present a straightforward protocol for the cleavage and functionalization of Csp3-Csp3 bonds in alkylbenzenes using photoredox catalysis. Our method employs two distinct bond scission pathways. For substrates with tertiary benzylic substituents, a carbocation-coupled electron transfer mechanism is prevalent. For substrates with primary or secondary benzylic substituents, a triple single-electron oxidation cascade is applicable. Our strategy offers a practical means of cleaving inert Csp3-Csp3 bonds in molecules without any heteroatoms, resulting in primary, secondary, tertiary, and benzylic radical species.

Salvage Radical Prostatectomy after Primary Focal Ablative Therapy: A Systematic Review and Meta-Analysis.

Focal therapy (FT) has been gaining popularity as a treatment option for localized intermediate-risk prostate cancer (PCa) due to the associated lower morbidity compared to whole-gland treatment. However, there is an increased risk of local cancer recurrence requiring subsequent treatment in a small proportion of patients. To conduct a systematic review and meta-analysis to better describe and analyze patient postoperative, oncologic, and functional outcomes for those who underwent salvage radical prostatectomy (sRP) to manage their primary FT failure. A systematic review was completed using three databases (PubMed, Embase, and CINAHL) from October to December 2021 to identify data on outcomes in patients who received sRP for cancer recurrence after prior focal treatment. 12 articles (482 patients) were included. Median time to sRP was 24 months. Median follow-up time was 27 months. A meta-analysis revealed a postoperative complication rate of 15% (95% CI: 0.09, 0.24), with 4.6% meeting criteria for a major complication Clavien (CG) grade ≥3. Severe GU toxicity was seen in 3.6% of the patients, and no patients had severe GI toxicity. Positive surgical margins (PSM) were found in 27% (95% CI: 0.19, 0.37). Biochemical recurrence (BCR) after sRP occurred in 23% (95% CI: 0.17, 0.30), indicating a BCR-free probability of 77% at 2 years. Continence (pad-free) and potency (ability to have penetrative sex) were maintained in 67% (95% CI: 0.53, 0.78) and 37% (95% CI: 0.18, 0.62) at 12 months, respectively. Our evidence shows acceptable complication rates and oncologic outcomes; however, with suboptimal functional outcomes for patients undergoing sRP for recurrent PCa after prior FT. Inferior outcomes were observed for salvage treatment compared to primary radical prostatectomy (pRP). More high-quality studies are needed to better characterize outcomes after this sequence of PCa treatments. We looked at treatment outcomes and toxicity for men treated with sRP for prior FT failure. We conclude that these patients will have significant detriment to genitourinary function, with outcomes being worse than those for pRP patients.

Ultrathin MoS2 nanosheet-wrapped Fe3O4 nanocrystals synergistically activate peroxymonosulfate for enhanced removal of organic pollutants

In peroxides-based advanced oxidation technologies (AOPs) using Fe-based catalysts, the low efficiency of Fe-ions cycling hinders their industrial applications. Recently, MoS2 has been validated to be a promising co-catalyst that can effectively promote the dynamic cycling of Fe-ions during the reaction. However, the activities of the reported MoS2-loaded Fe-based catalysts still decreased significantly after 3–5 cycling reactions, so it is necessary to develop a catalyst with high activity and stability. A series of MoS2 @Fe3O4-x (MF-x) catalysts were successfully constructed to trigger peroxymonosulfate (PMS) to eliminate the refractory organics. Ultrathin MoS2 nanosheets (∼ 5.7 nm) were uniformly and firmly coated on the surface of Fe3O4 nanoparticles via Fe–S bridging interaction. Pure MoS2 made little contribution to the climbazole (CBZ) degradation. Compared to the Fe3O4/PMS system, the adsorption and degradation efficiencies of the CBZ by MF-x/PMS system were improved by 7.5 and 4 times, respectively. The FeII/FeIII and MoIV/MoVI redox cycles on the MF-x surface could interact and work in synergy during the catalytic activation of PMS to degrade pollutants. MF-0.23 was an effective and stable catalyst for application over a wide pH range (2.0–9.8). Moreover, it efficiently dealt with other representative refractory contaminants with different pKa values, such as fluconazole (FZ), phenol, and rhodamine B (RhB). The primary active free radicals in MF-0.23/PMS system were detected to be O2•– and SO4•–. Specifically, the generated O2•– not only participated in the degradation of contaminants but also contributed to the MoIV regeneration. With outstanding catalytic activity, broad applicability, excellent reusability, and long-term stability, the MoS2 nanosheet-wrapped Fe3O4 nanocrystals should be an ideal heterogeneous catalyst for PMS-based AOPs.

INFLUENCE OF INTRAMOLECULAR DONOR-ACCEPTOR INTERACTIONS ON RADIOLYSIS OF ORGANIC COMPOUNDS: EFFECTS IN ACETYLACETONE

Using acetylacetone as an example, it was shown that the intramolecular hydrogen bond significantly affects the radiolytic transformations of organic compounds, suppressing the transfer of a proton from the primary radical cation to the molecule, and also contributing to the cleavage of the C–OH bond in the enol form. Due to these effects, the main heavy product of radiolysis at 295 K is 4-oxopent-2-en-2-yl acetate. Under boiling conditions (413 K), hydrogen bonds are eliminated, leading to the predominant formation of 4-hydroxy-2-pentanone, which is not detected at 295 K.

Phenyl-substituted cibalackrot derivatives: Redox behavior, structure-properties relationships and in situ UV-vis/EPR-spectroelectrochemistry of radical ions

Redox properties and UV–vis and EPR spectroelectrochemical behavior of cibalackrot (7,14-diphenyldiindolo[3,2,1-de:3′,2′,1′-ij][1,5]naphthyridine-6,13‑dione, 1) and its six derivatives 2 - 7 carrying two substituted phenyl rings have been examined. The dyes are of potential interest for organic electronics and singlet fission for solar energy conversion. The compounds are reduced in two reversible one-electron steps under formation of a stable primary radical anion. Oxidation yields the radical cation in a first reversible step and the second step is quasireversible. The presence of radical ions was confirmed by in situ UV–vis/EPR spectroelectrochemistry. The substituents have different influence on oxidation and on reduction, as revealed using the LFER approach and interpreted with the help of calculated energies of frontier orbitals. The observed first reduction (Ered1) and first oxidation (Eox1) potentials correlate well with the calculated values and their difference (ΔE1) has photophysical relevance because it reflects the energy of HOMO-LUMO gap.

Peculiarities in the Radiolysis of β-Diketones

Intramolecular hydrogen bonding has a significant effect on the radiolytic transformations of β- diketones. Using the radiolysis of acetylacetone as an example, it has been shown that a hydrogen bond between the hydroxyl and carbonyl in an enol prevents proton transfer from the primary radical cation to the neighboring molecule. As a result, the radiolytic formation of a keto alcohol (4-hydroxy-2-pentanone) was not observed at room temperature, but it was effective under boiling conditions. The intramolecular hydrogenbond contributed to a significant structural stress in the radical cation, which increased the yield of C–OH bond cleavage and the inhomogeneous formation of acetate (4-oxopent-2-en-2-yl acetate) under normal conditions

Advanced oxidation processes for pharmaceutical degradation and disinfection of wastewater: peracetic acid and graphene oxide quantum dots

A combination of graphene oxide quantum dots and peracetic acid (GQDs/PAA) was used to degrade sulfasalazine in municipal wastewater. The impact of reaction parameters such as initial concentrations of oxidant (peracetic acid) and drug (sulfasalazine) and different water matrices was evaluated. The degradation efficiency when using GQDs/PAA (50 mg/L: 0.10 mM) was almost 100% in synthetic water and 80% in municipal wastewater. The primary reactive radicals that caused the degradation of sulfasalazine in wastewater were identified as hydroxy (·OH) as well as the peroxy radicals (CH3C(=O)OO·, CH3C(=O)O·). 83.7% of total organic carbon were eliminated when 0.15 mM PAA was used while nearly 100% degradation of SZZ was achieved. A degradation pathway was proposed using the degradation intermediates obtained on quadrupole time-of-flight liquid chromatography mass spectrometry. The genotoxic and mutagenic potential of the degradation products formed during the degradation of sulfasalazine was assessed using the Ames test. It was demonstrated that none of the intermediates were mutagenic. GQDs/PAA was further tested as a potential disinfectant, and S. aureus was completely inactivated as verified by using LIVE/DEAD Baclight staining. In raw municipal wastewater, GQDs/PAA eliminated more than 90% of bacteria, thus confirming the synergy of GQDs/PAA as both a disinfectant and a photocatalyst.

Efficient photocatalytic degradation of antibiotics by visible light-driven red phosphorus/ZnAl-LDH heterostructures: Mineralization activity and actual farming wastewater treatment

A stable, efficient and pollution-free treatment system should be urgently developed to boost the application of green and sustainable photocatalytic materials in practical wastewater composite remediation. two-dimensional (2D) red phosphorus (RP)/ZnAl-LDH (Layered Double Hyroxides) photocatalyst photocatalysts were developed in this study. The optimized RPLDH0.8 (RP/ZnAl-LDH0.8)/Vis system was found with a high tetracycline hydrochloride (TC) degradation rate of 89% in 90 min. Moreover, the total organic carbon (TOC) removal rate was obtained as 21%. As indicated by the results of the experiments and characterization, the fast catalytic process arose from the S-scheme charge transfer pathway in RP/ZnAl-LDH. Furthermore, the liquid chromatography-mass spectrometry (LC-MS) and the radical capture assays were performed to investigate the probable TC photodegradation pathway and the primary reactive radicals in the photocatalytic process. The results of the bio-acute toxicity-based assays suggested that the RPLDH0.8/Vis system detoxified the transformation products. Lastly, the above RPLDH0.8/Vis system was found with high removal rates for other organic pollutants while showing high removal performance in different natural water bodies. Besides, the leaching concentration of total Zn in each of the five cycles of the degradation experiments was significantly lower than the national level discharge standard, suggesting that the RPLDH0.8/Vis system degraded TC without secondary heavy metal contamination. As revealed by the above findings, a novel strategy was proposed to prepare RP/ZnAl-LDH photocatalysts for the photocatalytic degradation of antibiotics.

Intercalation of Well-Dispersed Fe2 O3 with SnO2 toward Durable Peroxymonosulfate Activation to Eliminate Antibiotics: Performance and Mechanism.

Sustainable Fe2 O3 /SnO2 with fine interfacial feature derived from FeSnO(OH)5 was prepared and employed for elimination contaminants. The synergistic effect between Fe2 O3 and SnO2 endowed a remarkable degradation performance for tetracycline degradation. Well dispersed SnO2 can function as fine protective layer to enhance the anchoring of iron ions. In addition, SnO2 with excellent conductivity can accelerate electron transfer on the surface of Fe2 O3 , further activation PMS. Approximately 89.3% of tetracycline (TC) was removed in Fe2 O3 /SnO2 /PMS system, which was higher than alone Fe2 O3 /PMS (73.2%) and SnO2 /PMS (39.7%) systems. The operating parameters were evaluated and studied. Electron paramagnetic resonance (EPR) and quenching tests manifested that 1 O2 was primary active specie, and ⋅OH, ⋅SO4 - and ⋅O2 - were participated in the degradation process. Besides, degradation pathways were proposed by identifying the intermediate products. This work is expected to offer a potential design for construction eco-friendly heterogeneous catalyst toward wastewater treatment.

MP61-03 COMPARING THE OUTCOMES OF ROBOTIC ASSISTED RADICAL PROSTATECTOMY IN BLACK AND WHITE MEN: EXPERIENCE OF A HIGH-VOLUME CENTER

You have accessJournal of UrologyCME1 Apr 2023MP61-03 COMPARING THE OUTCOMES OF ROBOTIC ASSISTED RADICAL PROSTATECTOMY IN BLACK AND WHITE MEN: EXPERIENCE OF A HIGH-VOLUME CENTER Jonathan Noel, Marcio Moschovas, Abdel Rahman Jaber, Marco Sandri, Travis Rogers, and Vipul Patel Jonathan NoelJonathan Noel More articles by this author , Marcio MoschovasMarcio Moschovas More articles by this author , Abdel Rahman JaberAbdel Rahman Jaber More articles by this author , Marco SandriMarco Sandri More articles by this author , Travis RogersTravis Rogers More articles by this author , and Vipul PatelVipul Patel More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003319.03AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Global cancer incidence ranks Prostate Cancer (CaP) as the second highest overall, with Africa and the Caribbean having the highest mortality. Previous literature suggests disparities in CaP outcomes according to ethnicity, specifically functional and oncological are suboptimal in black men. However, recent data shows black men achieve post radical prostatectomy (RP) outcomes equivalent to white men in a universally insured system. Our objective is to compare outcomes of patients who self-identified their ethnicity as black or white undergoing RP at our institution. METHODS: From 2008 to 2017, 396 black and 4929 white patients underwent primary robotic-assisted radical prostatectomy (RARP) with a minimum follow-up of 5 years. Exclusion criteria were concomitant surgery and cancer status not available. A propensity score (PS) match was performed with a 1:1, 1:2, and 1:3 ratio without replacement. Primary endpoints were potency, continence recovery, biochemical recurrence (BCR), positive surgical margins (PSM), and post-operative complications. RESULTS: After PS 1:1 matching, 341 black vs. 341 white men with a median follow-up of approximately 8 years were analyzed. The overall potency and continence recovery at 12 months was 52% vs 58% (p=0.3) and 82% vs 89% (p=0.3), respectively. PSM rates was 13.4 % vs 14.4% (p=0.75). Biochemical recurrence and persistence PSA was 13.8% vs 14.1% and 4.4% vs 3.2% respectively (p=0.75).Clavien-Dindo complications (p=0.4) and 30-day readmission rates (p=0.5) were similar. CONCLUSIONS: In our study, comparing two ethnic groups with similar preoperative characteristics and full access to screening and treatment showed compatible RARP results. We could not demonstrate outcomes superiority in one group over the other. However, this data adds to the growing body of evidence that the racial disparity gap in prostate cancer outcomes can be narrowed if patients have appropriate access to prostate cancer management. It also could be used in counseling surgeons and patients on the surgical intervention and prognosis of prostate cancer in patients with full access to gold standard screening and treatment. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e853 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Jonathan Noel More articles by this author Marcio Moschovas More articles by this author Abdel Rahman Jaber More articles by this author Marco Sandri More articles by this author Travis Rogers More articles by this author Vipul Patel More articles by this author Expand All Advertisement PDF downloadLoading ...

Fluorescent switch-on probe for carbon-centered radicals and real-time assessment of toluene degradation efficacy

Carbon-centered radicals derived from parent compounds are primary radical intermediates involved in the degradation of organic pollutants. This study presents a bifunctional probe with a fluorescent "switch-on" and radical capture functions for in situ trapping and specific detection of carbon-centered radicals. Carbon-centered radicals can be quickly trapped and they can notably turn on the 11-fold fluorescence, which enables the monitoring of unstable and short-lived carbon-centered radicals generated during toluene degradation. The proposed system was applied to assess the toluene degradation efficacy in real time. The fluorescence response was similar to that of the toluene degradation efficiency measured using high-performance liquid chromatography (HPLC). In addition, the benzyl radical was identified as the primary carbon-centered radical intermediate by high-resolution liquid chromatography-mass spectrometry (LC-MS), which provides direct evidence for the toluene degradation mechanism by thermally activated persulfate.

Choline PET/CT in recurrent prostate cancer.

Biochemical recurrence (BR) occurs in up to 40% of patients with prostate cancer (PCa) treated with primary radical prostatectomy (RP). Choline PET/CT may show, in a single-step examination, the site of tumor recurrence earlier than traditional imaging methods, particularly at low prostate-specific antigen (PSA) levels, thus influencing subsequent treatment. Patients with recurrent and non-metastatic prostate cancer (nmPCa), who were assessed with choline PET/CT, were included in the analysis. Based on imaging results, the following therapeutic strategies were chosen: radiotherapy to the prostatic bed, androgen deprivation therapy (ADT), and chemotherapy or stereotactic body radiotherapy (SBRT) to either the pelvic lymph nodes or distant metastases. We assessed the impact of age, PSA levels, Gleason score (GS), and adjuvant therapy on oncological outcomes. Data from 410 consecutive nmPCa patients with BR who underwent RP as primary treatment were analyzed. One hundred seventy-six (42.9%) patients had a negative choline PET/CT, and 234 (57.1%) patients resulted positive. In the multivariate analysis, only chemotherapy and PSA at recurrence were significant independent prognostic factors on overall survival (OS). In the PET-positive subgroup, the number of relapses, PSA post-prostatectomy, and chemotherapy impacted on OS. PSA (post-surgery and at recurrence) affected progression-free survival (PFS) in the univariate analysis. In the multivariate analysis, GS, the number of relapse sites, and PSA (post-surgery and at recurrence) were significant prognostic factors for disease-free survival (DFS). Choline PET/CT provides better accuracy than conventional imaging for the assessment of nmPCa with BR after prostatectomy, thereby enabling salvage strategies and improving quality of life.

Insight into the kinetics and thermodynamic analyses of co-pyrolysis using advanced isoconversional method and thermogravimetric analysis: A multi-model study of optimization for enhanced fuel properties

Waste management is quite challenging and it has become a major concern across the globe. The most common wastes are in the form of polymers or plastics that are composed of a mixture of various commodity plastics like PE, PP, PVC, HDPE, LDPE, etc. Pyrolysis is found to be a promising technology for managing wastes as well as converting them into valuable hydrocarbons. The present study investigated to discern the synergism in thermal degradation behavior and to identify the interaction between polymer molecules in co-pyrolysis. The advanced isoconversional model was employed for trustworthy estimation of activation energy as the thermal effects on a reaction deviate the temperature of a sample from the set heating value. The results were also compared with the model-free methods to understand the synergism, reactivity, and thermodynamic system with the progress of the conversion. The activation energy was found to be lowest when the polymers were used in a certain proportion and the synergy effect was more significant when PP content was > 40 % in the mixture. The positive synergetic effect could be attributed to the intermolecular hydrogen transfer from a less stable polymer to a free radical de-propagating chain of the other polymer during thermal degradation. The complex governing thermochemical reaction mechanism was determined using the Criado master plot and the analysis revealed that with increasing PP content in a binary mixture the reaction mechanism shifted from R2 to R3. The high regression coefficient value (R2 > 0.99) in the regenerated TGA profiles signified a good agreement between the theoretical and experimental results. While thermodynamic analysis showed that the process was endothermic and non-spontaneous in nature. Moreover, the radical reaction during co-pyrolysis of polymers enhances intermolecular hydrogen transfer resulting in the formation of iso-alkane and iso-alkene along with secondary radicals, which undergo β-scission to form alkenes/dienes and short primary radicals. As a result, the enhanced intermolecular hydrogen transfer phenomenon initiates the co-pyrolysis reaction at a relatively lower activation energy compared to individual polymer molecules.

Study on the Mechanism of Molecular Weight Reduction of Polyethylene Based on Fe-Montmorillonite and Its Potential Application.

The reactions occurring in the oxidative degradation phase during the photo-oxidative degradation of polyethylene (PE) are the factors leading to molecular weight reduction. However, the mechanism of molecular weight reduction before oxidative degradation has not been clarified. The present study aims to investigate the photodegradation of PE/Fe-montmorillonite (Fe-MMT) films, especially molecular weight change. The results show the rate of photo-oxidative degradation of each PE/Fe-MMT film is much faster than that of the pure linear low-density polyethylene (LLDPE) film. A decrease in the molecular weight of polyethylene was also found in the photodegradation phase. Based on this, it was found that the transfer and coupling of primary alkyl radicals originating from photoinitiation lead to a decrease in the molecular weight of polyethylene, and the kinetic results validate this new mechanism well. This new mechanism is an improvement on the existing mechanism of molecular weight reduction during the photo-oxidative degradation of PE. In addition, Fe-MMT can greatly accelerate the reduction of PE molecular weight into small oxygen-containing molecules as well as induce cracks on the surface of polyethylene films, all of which can accelerate the biodegradation process of polyethylene microplastics. The excellent photodegradation properties of PE/Fe-MMT films will be useful in the design of more environmentally friendly degradable polymers.

Rare earth-doped mixed Ni–Cu–Zn ferrites as an effective photocatalytic agent for active degradation of Rhodamine B dye

In this study, a series of Gd3+-doped mixed Ni–Cu–Zn ferrites with composition of Zn0.5Ni0.3Cu0.2Fe2–xGdxO4 (x = 0, 0.025, 0.05, 0.075, 0.1) was prepared using self-ignition sol–gel method. The prepared nanoparticles with an average size ranging from 22 to 26 nm show a single-phase cubic structure belonging to the spinel matrix. A rise in the Gd3+ concentration leads to an increase in crystallite size and lattice parameter. In Fourier transform infrared spectra, two main absorption bands belonging to the spinel structure are observed. The high-frequency bands (υ1) represent the tetrahedral complex, while the low-frequency bands (υ2) signify the octahedral complex. The optical bandgap of the nanoferrites is found within the range of 2.91 to 2.41 eV, depending on their size. The magnetic characteristics of the material, such as saturation magnetization and coercivity are significantly altered with the concentration of Gd3+ in the solution. Using Rhodamine B (RhB) as a model organic pollutant, an in-depth investigation of the photocatalytic activity of the compounds was carried out. The present outcomes show that adding an adequate amount of Gd3+ significantly enhances the number of hydroxyl radicals produced by the ferrite, in turn, increasing the photocatalytic activity of the material. Mechanism elucidated by scavenger studies reveals that •OH and holes are the primary reactive radicals responsible for the degradation process. Prepared photocatalysts show an insignificant performance loss in five consecutive cycles. Thus, it is concluded that these photocatalysts are highly suitable for the remediation of dye-contaminated wastewater.

Long-Term Outcomes of Stereotactic Body Radiotherapy (SBRT) for Intraprostatic Relapse after Definitive Radiotherapy for Prostate Cancer: Patterns of Failure and Association between Volume of Irradiation and Late Toxicity.

The aim of this retrospective study was to assess the adverse effects and outcomes of salvage re-irradiation with stereotactic body radiotherapy (sSBRT) for local recurrence of prostate cancer (PCa) after definitive radiotherapy (RT). The study was focused on the adverse effects and prognostic factors for treatment toxicity, followed by an analysis of patterns of failure and survival. Patients treated with sSBRT between 2012 and 2020 at a tertiary institution were included. The exclusion criteria were a primary or salvage radical prostatectomy or a palliative sSBRT dose. Patients with oligorecurrence were eligible if all metastatic lesions were treated locally with curative intent. The Kaplan-Meier method was used to estimate time to grade ≥ 3 toxicity, local control (LC), freedom from distant metastases (FFDM), progression-free survival (PFS), biochemical control (BC) and overall survival (OS). The differences between groups (focal vs. whole-gland sSBRT) were compared using the log-rank test. The Cox proportional hazards model was used to assess prognostic factors for the listed endpoints. A total of 56 patients with a median age of 70.9 years and a median follow-up of 38.6 months were included in the analysis. The majority of them received local sSBRT only (45; 80.4%), while the rest were simultaneously treated for oligometastases (11; 19.6%). Overall, 18 (32.1%) patients experienced any grade ≥ 3 toxicity, including 1 (6.7%) patient who received focal sSBRT, and 17 (41.5%) patients treated with whole-gland sSBRT. The Planning Target Volume (per cc; HR 1.01; 95% CI 1-1.02; p = 0.025) and use of ADT (yes vs. no; HR 0.35; 95%CI 0.13-0.93; p = 0.035) were independent prognostic factors for the risk of grade ≥ 3 toxicity. The estimated rate of grade ≥ 3 adverse events was significantly higher (43.8% vs. 7.1% at 2 years; p = 0.006), and there was no improvement in the LC (92.9% vs. 85.3% at 2 years; p = 0.759) in patients treated with whole-gland sSBRT compared to focal sSBRT. The 2- and 5-year LC were 87.6% and 47.9%, respectively; the 2- and 5-year FFDM were 72.7% and 42.8%, respectively; and the 2- and 5-year PFS were 67.9% and 28.7%, respectively. The primary pattern of failure was distant metastasis. The sSBRT for local recurrence of PCa after definitive RT was associated with a high risk of severe grade ≥ 3 toxicity, which significantly increased with the volume and extent of re-irradiation.

Experimental chemical budgets of OH, HO2, and RO2 radicals in rural air in western Germany during the JULIAC campaign 2019

Abstract. Photochemical processes in ambient air were studied using the atmospheric simulation chamber SAPHIR at Forschungszentrum Jülich, Germany. Ambient air was continuously drawn into the chamber through a 50 m high inlet line and passed through the chamber for 1 month in each season throughout 2019. The residence time of the air inside the chamber was about 1 h. As the research center is surrounded by a mixed deciduous forest and is located close to the city Jülich, the sampled air was influenced by both anthropogenic and biogenic emissions. Measurements of hydroxyl (OH), hydroperoxyl (HO2), and organic peroxy (RO2) radicals were achieved by a laser-induced fluorescence instrument. The radical measurements together with measurements of OH reactivity (kOH, the inverse of the OH lifetime) and a comprehensive set of trace gas concentrations and aerosol properties allowed for the investigation of the seasonal and diurnal variation of radical production and destruction pathways. In spring and summer periods, median OH concentrations reached 6 × 106 cm−3 at noon, and median concentrations of both HO2 and RO2 radicals were 3 × 108 cm−3. The measured OH reactivity was between 4 and 18 s−1 in both seasons. The total reaction rate of peroxy radicals with NO was found to be consistent with production rates of odd oxygen (Ox= NO2 + O3) determined from NO2 and O3 concentration measurements. The chemical budgets of radicals were analyzed for the spring and summer seasons, when peroxy radical concentrations were above the detection limit. For most conditions, the concentrations of radicals were mainly sustained by the regeneration of OH via reactions of HO2 and RO2 radicals with nitric oxide (NO). The median diurnal profiles of the total radical production and destruction rates showed maxima between 3 and 6 ppbv h−1 for OH, HO2, and RO2. Total ROX (OH, HO2, and RO2) initiation and termination rates were below 3 ppbv h−1. The highest OH radical turnover rate of 13 ppbv h−1 was observed during a high-temperature (max. 40 ∘C) period in August. In this period, the highest HO2, RO2, and ROX turnover rates were around 11, 10, and 4 ppbv h−1, respectively. When NO mixing ratios were between 1 and 3 ppbv, OH and HO2 production and destruction rates were balanced, but unexplained RO2 and ROX production reactions with median rates of 2 and 0.4 ppbv h−1, respectively, were required to balance their destruction. For NO mixing ratios above 3 ppbv, the peroxy radical reaction rates with NO were highly uncertain due to the low peroxy radical concentrations close to the limit of NO interferences in the HO2 and RO2 measurements. For NO mixing ratios below 1 ppbv, a missing source for OH and a missing sink for HO2 were found with maximum rates of 3.0 and 2.0 ppbv h−1, respectively. The missing OH source likely consisted of a combination of a missing inter-radical HO2 to OH conversion reaction (up to 2 ppbv h−1) and a missing primary radical source (0.5–1.4 ppbv h−1). The dataset collected in this campaign allowed analyzing the potential impact of OH regeneration from RO2 isomerization reactions from isoprene, HO2 uptake on aerosol, and RO2 production from chlorine chemistry on radical production and destruction rates. These processes were negligible for the chemical conditions encountered in this study.