Excited-State Identification of a Nickel-Bipyridine Photocatalyst by Time-Resolved X-ray Absorption Spectroscopy.

Photoassisted catalysis using Ni complexes is an emerging field for cross-coupling reactions in organic synthesis. However, the mechanism by which light enables and enhances the reactivity of these complexes often remains elusive. Although optical techniques have been widely used to study the ground and excited states of photocatalysts, they lack the specificity to interrogate the electronic and structural changes at specific atoms.

Disentangling Thermal from Electronic Contributions in the Spectral Response of Photoexcited Perovskite Materials.

Disentangling electronic and thermal effects in photoexcited perovskite materials is crucial for photovoltaic and optoelectronic applications but remains a challenge due to their intertwined nature in both the time and energy domains. In this study, we employed temperature-dependent variable-angle spectroscopic ellipsometry, density functional theory calculations, and broadband transient absorption spectroscopy spanning the visible to mid-to-deep-ultraviolet (UV) ranges on MAPbBr thin films. The use of deep-UV detection opens a new spectral window that enables the exploration of high-energy excitations at various symmetry points within the Brillouin zone, facilitating an understanding of the ultrafast responses of the UV bands and the underlying mechanisms governing them.

Disentangling the evolution of electrons and holes in photoexcited ZnO nanoparticles.

The evolution of charge carriers in photoexcited room temperature ZnO nanoparticles in solution is investigated using ultrafast ultraviolet photoluminescence spectroscopy, ultrafast Zn K-edge absorption spectroscopy, and molecular dynamics (MD) simulations. The photoluminescence is excited at 4.66 eV, well above the band edge, and shows that electron cooling in the conduction band and exciton formation occur in <500 fs, in excellent agreement with theoretical predictions.

Incidental follicular cholecystitis with periductal fibrosis on liver biopsy: Rare findings.

Introduction And Importance: Follicular cholecystitis (FC) is a rare entity found, it is found in 0.1-1 % of patients with chronic cholecystitis. 1,2 This pathologic finding has been associated with extrahepatic biliary obstruction distal to the gallbladder, such as primary sclerosing cholangitis, choledocholithiasis, and distal biliary strictures.

Charge Carrier Screening in Photoexcited Epitaxial Semiconductor Nanorods Revealed by Transient X-ray Absorption Linear Dichroism.

Understanding the electronic structure and dynamics of semiconducting nanomaterials at the atomic level is crucial for the realization and optimization of devices in solar energy, catalysis, and optoelectronic applications. We report here on the use of ultrafast X-ray linear dichroism spectroscopy to monitor the carrier dynamics in epitaxial ZnO nanorods after band gap photoexcitation. By rigorously subtracting out thermal contributions and conducting calculations, we reveal an overall depletion of absorption cross sections in the transient X-ray spectra caused by photogenerated charge carriers screening the core-hole potential of the X-ray absorbing atom.

Time-resolved Element-selective Probing of Charge Carriers in Solar Materials.

We review our recent results on the implementation of picosecond (ps) X-ray absorption spectroscopy to probe the electronic and geometric structure of centres formed by photoexcitation of solar materials such as TiO2 polymorphs and inorganic Cs-based perovskites. The results show electron localization at Ti defects in TiO2 anatase and rutile and small hole polaron formation in the valence band of CsPbBr3, all within 80 ps. This method is promising for the study of the ultrafast time scales of such processes, especially with the advent of the Swiss X-ray Free Electron Laser (SwissFEL).

Interfacial Electron Injection Probed by a Substrate-Specific Excitonic Signature.

Ultrafast interfacial electron transfer in sensitized solar cells has mostly been probed by visible-to-terahertz radiation, which is sensitive to the free carriers in the conduction band of the semiconductor substrate. Here, we demonstrate the use of deep-ultraviolet continuum pulses to probe the interfacial electron transfer, by detecting a specific excitonic transition in both N719-sensitized anatase TiO and wurtzite ZnO nanoparticles. Our results are compared to those obtained on bare nanoparticles upon above-gap excitation.

The LOUVRE Laboratory: State-of-the-Art Ultrafast Ultraviolet Spectroscopies for Molecular and Materials Science.

We describe the facilities for ultraviolet studies in the femtosecond to nanosecond time domain. These facilities consist of: i) a set-up for deep-ultraviolet spectroscopy in the 260-380 nm range in both pump and probe pulses for transient absorption/reflectivity or two-dimensional spectroscopy studies; ii) a set-up for ultrafast fluorescence measurements with detection down to 300 nm. The capabilities of these set-ups are demonstrated by examples on molecular systems, biosystems, nanoparticles and solid materials.

Somatic Testing on Gynecological Cancers Improve the Identification of Lynch Syndrome.

Objective: Recent data from the literature indicate gynecological cancers (GCs) as sentinel cancers for a diagnosis of Lynch syndrome (LS). Clinical approaches to identifying LS have low sensitivity, whereas somatic tests on GCs may be a more sensitive and cost-effective strategy.

Methods: A series of 78 GCs belonging to 74 patients sent to the Genetic Counselling Service were investigated using microsatellite instability, immunohistochemical expression of mismatch repair (MMR) genes, and MLH1 promoter methylation.

Quiescence of human muscle stem cells is favored by culture on natural biopolymeric films.

Background: Satellite cells are quiescent resident muscle stem cells that present an important potential to regenerate damaged tissue. However, this potential is diminished once they are removed from their niche environment in vivo, prohibiting the long-term study and genetic investigation of these cells. This study therefore aimed to provide a novel biomaterial platform for the in-vitro culture of human satellite cells that maintains their stem-like quiescent state, an important step for cell therapeutic studies.

Localized holes and delocalized electrons in photoexcited inorganic perovskites: Watching each atomic actor by picosecond X-ray absorption spectroscopy.

We report on an element-selective study of the fate of charge carriers in photoexcited inorganic CsPbBr and CsPb(ClBr) perovskite nanocrystals in toluene solutions using time-resolved X-ray absorption spectroscopy with 80 ps time resolution. Probing the Br K-edge, the Pb L-edge, and the Cs L-edge, we find that holes in the valence band are localized at Br atoms, forming small polarons, while electrons appear as delocalized in the conduction band. No signature of either electronic or structural changes is observed at the Cs L-edge.

Jejunitis and brown bowel syndrome with multifocal carcinogenesis of the small bowel.

This is the first report describing a case where prolonged, severe malabsorption from brown bowel syndrome progressed to multifocally spread small bowel adenocarcinoma. This case involves a female patient who was initially diagnosed with chronic jejunitis associated with primary diffuse lymphangiectasia at the age of 26 years. The course of the disease was clinically, endoscopically, and histologically followed for 21 years until her death at the age 47 due to multifocal, metastasizing adenocarcinoma of the small bowel.

Collagenous colitis associated with protein losing enteropathy in a toddler.

Collagenous mucosal inflammatory disease is a rare gastrointestinal disorder that involves the columnar lining of gastric and intestinal mucosa and is characterized by a distinct subepithelial collagen deposition. Recent clinical and pathological evidence have indicated that collagenous mucosal inflammatory disease can be extensive disease that may concomitantly involve several gastrointestinal sites at the same time. This entity, however, occurs infrequently in children.

Local anesthetic versus forced coughing at colposcopic-guided biopsy: a prospective study.

Objective: To evaluate whether the administration of local anesthetic (LA) reduces pain in comparison with forced coughing (FC) for the execution of colposcopically guided biopsies (CGBs).

Study Design: Data of 100 consecutive patients undergoing CGBs with the use of LA or FC were prospectively evaluated. Procedure-related pain was assessed with the use of a 100-mm visual analogue scale.

Brown bowel syndrome: a rare complication in diseases associated with long-standing malabsorption.

Background/aims: Longtime chronic malabsorption may among other things cause a lack of liposoluble vitamins. Vitamin E deficiency can lead to formation of lipofuscin aggregates. Its deficiency is also associated with an increased lipofuscinosis of the bowel, i.

Colon capsule endoscopy: detection of colonic polyps compared with conventional colonoscopy and visualization of extracolonic pathologies.

Background: Conventional colonoscopy (CC) is the gold standard for diagnostic examination of the colon. However, the overall acceptance of this procedure is low due to patient fears of complications or embarrassment. Colon capsule endoscopy (CCE) represents a minimally invasive, patient-friendly procedure that offers complete visualization of the entire intestine.

Massive panniculectomy results in improved functional outcome.

Background: Panniculus morbidus is a large abdominal apron found in morbidly obese patients. This condition creates a vicious cycle of weight gain and functional incapacity. Our study assessed the functional improvement in patients undergoing massive panniculectomy.

Body composition analysis in bariatric surgery: use of air displacement plethysmograph.

Body weight, body mass index (BMI), and percent excess weight loss are used to assess patient outcomes after bariatric surgery; however, they provide little insight into the true nature of the patient's weight loss. Body composition measurements monitor fat versus lean mass losses to permit interventions to reduce or avoid lean body mass loss after bariatric surgery. A retrospective review of patients who underwent bariatric surgery between 2002 and 2008 was performed.

Capsule endoscopy in patients with cardiac pacemakers and implantable cardioverter-defibrillators - a retrospective multicenter investigation.

Background & Aims: Capsule endoscopy (CE) is an established tool for the investigation of the small intestine. The Food and Drug Administration, Given Imaging and Olympus have not recommended the use of capsule endoscopy in patients with cardiac pacemakers and implantable cardioverter defibrillators (ICDs). The aim of this retrospective study was to investigate the safety of capsule endoscopy systems (Given Imaging and Olympus) when applied in patients with different types of pacemakers/ICDs in vivo.

Parenteral fish oil-associated burr cell anemia.

We report the development of burr cell anemia in an infant with short bowel syndrome who received parenteral fish oil (Omegaven, Fresenius-Kabi, Graz, Austria) after development of total parenteral nutrition-associated liver disease. Parenteral fish oil was discontinued, and the burr cell anemia disappeared, suggesting that parenteral fish oil might be associated with hemolytic anemia.

The use of Lactobacillus rhamnosus in the therapy of bacterial vaginosis. Evaluation of clinical efficacy in a population of 40 women treated for 24 months.

Background: Bacterial vaginosis (BV) is the most prevalent vaginal disorder in adult women worldwide. A number of clinical studies indicate that re-establishment of the physiological ecosystem by re-colonization of vaginal mucosa by lactobacilli may be an effective therapy for BV both after initial antimicrobial therapy or when given alone. A vaginal pH <4.

Mast cell tryptase in sera of patients with Crohn's disease and mastocytosis.

Introduction: The pathogenesis of Crohn's disease is unclear, but an abnormal immune response seems to play an important role. This study investigated whether serum tryptase could be shown in Crohn's disease as a marker of disease.

Materials And Methods: Mast cell tryptase was detected in sera of 48 patients with active Crohn's disease, 31 patients with inactive Crohn's disease, 17 patients with mastocytosis, and 50 controls.

Long-term partial remission of autoimmune thrombocytopenia in a patient treated with the anti-tumor necrosis factor-alpha antibody infliximab for refractory fistulizing Crohn's disease.

Background: Up to the present date, the treatment of recurrent chronic fistulas occurring with Crohn's disease represents a challenging task for both internists and surgeons alike.

Methods: Conservative methods of treatment using steroids, dietotherapy, antibiotics or immunosuppressive agents are not particularly effective in treating fistulas. Treatment with anti-tumor necrosis factor-alpha (TNFalpha) antibodies results in more remissions of fistulas.