Publications by authors named "Christopher P"

Designing catalysts with well-defined active sites with chemical functionality responsive to visible light has significant potential for overcoming scaling relations limiting chemical reactions over heterogeneous catalyst surfaces. Visible light can be leveraged to facilitate the removal of strongly bound species from well-defined single cationic sites (Rh) under mild conditions (323 K) when they are incorporated within a photoactive perovskite oxide (Rh-doped SrTiO). CO, a key intermediate in many chemistries, forms stable geminal dicarbonyl Rh complexes (Rh(CO)), that could act as site blockers or poisons during a catalytic cycle.

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Acute appendicitis is one of the most common emergency surgical conditions, typically treated by laparoscopic appendectomy in most centres. Post-operative ascites is a rare complication after laparoscopic surgery, especially in the absence of a bowel, urinary tract or lymphatic injury. This condition creates a diagnostic challenge for surgeons, even after thorough investigation.

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Currently, hydroquinone serves as topical treatment of choice for melasma. However, its long-term use was associated with melanocyte toxicity. Cysteamine is an aminothiol that possesses antioxidant and depigmenting properties, therefore potentially suitable for treating melasma.

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Catalysis stands as an indispensable cornerstone of modern society, underpinning the production of over 80% of manufactured goods and driving over 90% of industrial chemical processes. As the demand for more efficient and sustainable processes grows, better catalysts are needed. Understanding the working principles of catalysts is key, and over the last 50 years, surface-enhanced Raman Spectroscopy (SERS) has become essential.

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Redox reactions on the surface of transition metal oxides are of broad interest in thermo, photo, and electrocatalysis. H temperature-programmed reduction (H-TPR) is commonly used to probe oxide reducibility by measuring the rate of H consumption during temperature ramps, assuming that this rate is controlled by oxide reduction. However, oxide reduction involves several elementary steps, such as H dissociation and H-spillover, before surface reduction and HO formation occur.

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  • Closed-loop recycling of plastics is crucial for meeting the increasing material demands of a growing population while conserving nonrenewable resources.
  • The study focuses on the chemical recycling of polyurethane foams (PUFs) through acidolysis using dicarboxylic acids (DCAs) to obtain high-quality recyclable polyols.
  • Findings reveal that the structure of DCAs significantly affects the speed of the recycling process, specifically how quickly polyols can be released, with key insights into the mechanisms at play allowing for improved recycling methods.
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  • - Nonthermal plasmas offer a novel method for enhancing electrically driven catalytic processes, but the core activation mechanisms are still not well understood.
  • - Research shows that exposure to a nonthermal plasma in an argon atmosphere significantly lowers the binding energy of carbon monoxide (CO) on platinum nanoparticles, particularly at less coordinated sites.
  • - The observed reduction in binding energy, influenced by plasma density, is explained by plasma-induced charging and electric fields affecting the catalyst surface, indicating a direct link between plasma exposure and enhanced catalytic activity.
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  • A giant inguinoscrotal hernia can extend below the midpoint of the thigh and is often due to patient neglect and fear of surgery.
  • Patients usually experience lower urinary tract symptoms and may develop ulcers from urine dribbling, with rare cases of obstruction or strangulation.
  • This case involved a successful laparoscopic repair of an uncomplicated giant inguinoscrotal hernia through preoperative optimization techniques, including BOTOX and progressive pneumoperitoneum, highlighting the importance of patient preparation for surgical interventions.
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  • The text references a correction to an article, implying there were errors or inaccuracies in the original publication.
  • The DOI (Digital Object Identifier) given indicates the specific article being referenced for correction.
  • This correction ensures that readers have access to the most accurate and reliable information related to that article.
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Catalysts containing Pt nanoparticles and reducible transition-metal oxides (WO, NbO, TiO) exhibit remarkable selectivity to aromatic products in hydrodeoxygenation (HDO) reactions for biomass valorization, contrasting the undesired aromatic hydrogenation typically observed for metal catalysts. However, the active site(s) responsible for the high selectivity remains elusive. Here, theoretical and experimental analyses are combined to explain the observed HDO reactivity by interrogating the organization of reduced WO domains on Pt surfaces at sub-monolayer coverage.

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Colorectal cancer is one of the most widespread types of cancer that still causes many deaths worldwide. The development of new diagnostic and prognostic markers, as well as new therapeutic methods, is necessary. The calcitonin gene-related peptide (CGRP) neuropeptide alongside its receptor calcitonin receptor-like receptor (CRLR) could represent future biomarkers and a potential therapeutic target.

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The use of visible photon fluxes to influence catalytic reactions on metal nanoparticle surfaces has attracted attention based on observations of reaction mechanisms and selectivity not observed under equilibrium heating. These observations suggest that photon fluxes can selectively impact the rates of certain elementary steps, creating nonequilibrium energy distributions among various reaction pathways. However, quantitative studies validating these hypotheses on metal nanoparticle surfaces are lacking.

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Aim: The study aims to contribute in reducing postoperative sequelae and to determine the optimal corticosteroid for reducing postoperative inflammation, pain, swelling, wound healing and quality of life in patients undergoing surgical extraction of impacted mandibular third molars.

Materials And Methods: The study included 191 patients who presented to the Department of Oral and Maxillofacial Surgery at Thai Moogambigai Dental College and Hospital in Chennai with bilateral impacted mandibular third molars that needed surgical removal. The effects of pre-emptive single dose of dexamethasone and methylprednisolone on pain, oedema, trismus, wound healing, and quality of life after surgical extraction of impacted lower third molars were investigated.

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  • Polyurethane (PU) is a widely used plastic, and recovering its valuable components through chemical recycling is crucial for managing its waste.
  • Acidolysis, specifically using dicarboxylic acid (DCA) vapor at lower temperatures (<150 °C), offers an effective way to recover polyol from PU waste without the issues seen in high-temperature methods.
  • This green chemistry approach minimizes unwanted byproducts and simplifies the process, making it easier to scale up and apply to commercial PU foam waste.
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Introduction: Ventral hernia repairs, particularly laparoscopic ventral hernia repair (LVHR), have become common procedures among general surgeons worldwide. Despite the benefits of LVHR, acute postoperative pain remains a significant concern. Transversus abdominis plane (TAP) blocks have been employed to alleviate postoperative pain in various laparoscopic procedures.

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Chemical recycling of polyurethane (PU) waste is essential to displace the need for virgin polyol production and enable sustainable PU production. Currently, less than 20% of PU waste is downcycled through rebinding to lower value products than the original PU. Chemical recycling of PU waste often requires significant input of materials like solvents and slow reaction rates.

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Although sea snakes (Elapidae) are commonly encountered by fishermen, accurately authenticated envenomings by them are uncommon in clinical literature. We report an authenticated case of Shaw's short, or spine-bellied, sea snake () bite in a young fisherman from northern Sri Lanka. The patient had clinical and biochemical evidence of mild transient myotoxicity but no evidence of neuromuscular paralysis or significant renal injury.

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  • Strong metal-support interactions (SMSIs) can cause platinum (Pt) to be encapsulated by oxide supports, typically observed in reducible oxides like TiO and NbO.
  • This study demonstrates that amorphous native surface oxide of aluminum nanocrystals (AlNCs) can also exhibit SMSI-induced Pt encapsulation when subjected to hydrogen reduction at 300 °C, leading to isolated Pt single-atom sites being exposed for catalysis.
  • The findings suggest that the native oxide on AlNCs allows for a well-defined environment for Pt atoms and promote further research into SMSIs with various materials, potentially leading to enhanced photocatalytic applications due to their unique plasmonic properties.
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  • Single-atom catalysts (SACs) utilize metals more efficiently and show different reactivity compared to traditional metal nanoparticles.
  • The study reveals that platinum SACs (Pt SAs) on anatase TiO support display different coordination environments depending on which surface (001 or 101) they are on, affecting their reactivity.
  • Findings indicate that Pt SAs beneath the (001) surface have lower reactivity due to reduced access to gas, highlighting the importance of understanding heterogeneous coordination environments in the development of SACs.
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The optoelectronic and charge transport properties of eight linearly fused Napthadithiophene (NDT) molecules with different electron-withdrawing (EWG) and electron-donating (EDG) substituents are studied using the density functional theory (DFT) methods. The effect of the substitution of EWG and EDG on the molecular structure, frontier molecular orbitals, ionization energy, electron affinity, reorganization energy, crystal packing, and charge carrier mobility are studied. The crystal structure simulation method is used to optimize the possible crystal packing arrangements for the studied molecules.

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  • The study explores the civil commitment hearing process for individuals with severe opioid use, focusing on their personal experiences and perceptions.
  • Two-thirds of participants were transported by police, and the entire commitment process, from arrival to transfer, was time-consuming, averaging over 5 hours, with minimal lawyer interaction.
  • Gender differences were noted, with men reporting longer wait times and women expressing more dissatisfaction with their interactions during the process.
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Total extraperitoneal approach for laparoscopic inguinal hernia repair (L-TEP) allows for better dissection, lesser chance of bowel injury, and quicker operating time. However robotic groin hernia repair is currently performed only through transabdominal route as it allows for more mobility of the arms. This study is aimed at studying the feasibility and outcomes of robotic totally extraperitoneal (R-TEP).

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  • The introduction of platinum-group metals (PGMs) to cerium oxide (CeO) enhances redox surface reactions, particularly hydrogen (H) dissociation and surface reduction, which are important in heterogeneous catalysis.
  • Research utilized various methods, including temperature-programmed reduction (TPR) and in situ spectroscopy, to investigate how platinum (Pt) nanoclusters and single atoms affect H reactions on Pt/CeO powder catalysts.
  • Key findings indicate that Pt significantly speeds up H consumption rates even on small fractions of CeO, alters the mechanism for H activation, and leads to localized changes in Ce distribution at CeO boundaries, ultimately improving H reaction efficiency compared to pure CeO.
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