A Stable Integrated Photoelectrochemical Reactor for H₂ Production from Water Attains a Solar‐to‐Hydrogen Efficiency of 18 % at 15 Suns and 13 % at 207 Suns

The major challenge in solar water splitting to H_{2} and O_{2} is in making a stable and affordable system for large‐scale applications. We have designed, fabricated, and tested a photoelectrochemical reactor characterized as follows: 1) it comprises an integrated device to reduce the balance of the system cost, 2) it utilizes concentrated sunlight to reduce the photoabsorber cost, and 3) it employs and alkaline electrolyte to reduce catalyst cost and eliminate external thermal management needs. The system consists of an III‐V‐based photovoltaic cell integrated with Ni foil as an O_{2} evolution catalyst that also protects the cell from corrosion. At low light concentration, without the use of optical lenses, the solar‐to‐hydrogen (STH) efficiency was 18.3 %, while at high light concentration (up to 207 suns) with the use of optical lenses, the STH efficiency was 13 %. Catalytic tests conducted for over 100 hours at 100–200 suns showed no sign of degradation nor deviation from product stoichiometry (H_{2}/O_{2}=2). Further tests projected a system stability of years

Schwannome benin primitif retrovesical : une tumeur très rare à propos d'un cas

Le schwannome est une tumeur le plus souvent bénigne, d'origine nerveuse se développant à partir des cellules de la gaine de Schwann. C'est une tumeur très rare tant par sa fréquence que par sa localisation rétrovésicale. L'examen anatomopathologique et immunohistochimique confirme le type histologique ainsi que le caractère bénin ou malin du schwannome. En raison des récidives, et du risque de transformation maligne, l'exérèse doit être complète. Nous rapportons le cas d'un patient âgé de 39 ans, admis pour une douleur pelvienne chronique à type de pesanteur, des signes irritatifs du bas appareil urinaire, et des troubles de transit. L'imagerie (échographie, TDM, IRM) a révélé la présence d'une masse pelvienne rétrovésicale, à paroi fine, latéralisée à gauche, mesurant 68x70x70 mm, exerçant un effet de masse sur la vessie et le sigmoïde. L'intervention chirurgicale menée par une laparotomie médiane a permis l'exérèse d'une masse retrovésicale bien encapsulée. L'examen anatomopathologique et immunohistochimique ont conclu à un schwannome bénin. La récidive et la transformation maligne bien que rare après chirurgie impose une surveillance post opératoire clinique et tomodensitométrique annuelle.Pan African Medical Journal 2016; 2

An Overview of the Photocatalytic Water Splitting over Suspended Particles

The conversion of solar to chemical energy is one of the central processes considered in the emerging renewable energy economy. Hydrogen production from water splitting over particulate semiconductor catalysts has often been proposed as a simple and a cost-effective method for large-scale production. In this review, we summarize the basic concepts of the overall water splitting (in the absence of sacrificial agents) using particulate photocatalysts, with a focus on their synthetic methods and the role of the so-called “co-catalysts”. Then, a focus is then given on improving light absorption in which the Z-scheme concept and the overall system efficiency are discussed. A section on reactor design and cost of the overall technology is given, where the possibility of the different technologies to be deployed at a commercial scale and the considerable challenges ahead are discussed. To date, the highest reported efficiency of any of these systems is at least one order of magnitude lower than that deserving consideration for practical applications

Pre-therapeutic lymphocytopenia: a new prognostic factor for failure of endovesical BCG-immunotherapy in non-muscle invasive bladder cancer

Abstract Background Inflammation plays a key role in the initiation and development of cancers. The prognostic value of inflammation biomarkers is proven in several urological and non-urological cancers. Knowing that the mechanism of action of endovesical BCG-immunotherapy in the treatment of non-muscle-invasive bladder cancer (NMIBC) is based on inflammation; lymphocytes have a key role in this reaction, particularly in the cytotoxic phase and can be predictive biomarkers of the response to BCG-therapy. The main objective of our work is therefore to study the impact of the number of lymphocytes on the response to endovesical BCG-immunotherapy, and more specifically lymphocytopenia (Lp) as a prognostic factor for BCG-failure. Methods Our study is a monocentric retrospective cohort carried for prognostic purposes, including 200 patients neodiagnosed with non-muscle-invasive bladder cancer (Ta -T1 stages), who required adjuvant treatment to TURB by BCG-immunotherapy, over a period of 5 years from January 2012 to December 2016. The cutoff value chosen was 1.67 × 109/L using maximized Log-Rank test. Survival analysis was studied using a Kaplan–Meier model. The comparison between the thresholds (L ≤ Vs > 1.67 × 109/L) concerning the recurrence and progression rates was carried out using the Log-Rank test. The association between lymphocytopenia and BCG-therapy failure was assessed in univariate and multivariate analysis by the Cox model. Statistical analysis was performed using Jamovi statistical software. Results One hundred and eight patients had a lymphocyte count > 1.67 × 109/L while 92 had a lymphocyte count ≤ 1.67 × 109/L. The median lymphocyte value was 1.64 (1.19; 2.4). The median survival without failure of BCG treatment was significantly better in the high lymphocyte-count group, with median of 22 months in the > 1.67 × 109/L group versus 11 months until failure in the ≤ 1.67 × 109/L group. A lymphocyte count ≤ 1.67 × 109/L was associated with failure of BCG-therapy in univariate (HR = 4.80, P ≤ 0.001) and multivariate (HR = 1.88, P = 0.025) studies. Other factors associated in the univariate study were found: T1 stage (P = 0.001), high-grade urothelial carcinoma (P = 0.001), multifocal tumor (P = 0.001), tumor size > 3 cm (P = 0.001), concomitant carcinoma in situ (Cis) (P = 0.001) and vascular emboli (P = 0.001). Multivariate study showed significant factors that are, in addition to lymphocytopenia, the presence of T1 stage (P = 0.011) and vascular emboli (P = 0.013). Conclusion Our study has shown an association between lymphocytes count and NMIBC progression. Patients with lymphocytopenia carry an increased risk of endovesical BCG-immunotherapy failure. These results should be further validated

Zinner’s Syndrome: A Rare Diagnosis of Dysuria Based on Imaging

Zinner’s syndrome is a rare congenital malformation of the seminal vesicle and ipsilateral upper urinary tract, due to developmental arrest in early embryogenesis of the Müllerian duct. Clinical presentation is nonspecific and includes voiding symptoms such as dysuria, ejaculatory disorders, and hypogastric or perineal pain. The diagnosis is made with imaging techniques, notably Magnetic Resonance Imaging (MRI) which remains the gold standard exam for diagnosis confirmation and therapeutic management. Treatment options depend on the severity of symptoms, the size of the cyst, and the complications. Herein, we report a rare case of a 33-year-old young patient who presented recurrent dysuria and ejaculatory disorders for the last 5 years. Imaging studies revealed an empty left renal fossa, with cystic pelvic mass related to the seminal vesicle and which was compatible with the diagnosis of Zinner’s syndrome. The patient underwent successful laparoscopic removal of the cyst and seminal vesicle, with total disappearance of urinary and sexual complaints with a 3-year follow-up

Medullary Aplasia Revealing a Metastatic Prostatic Adenocarcinoma

In this case report, we are reporting the case of a 68-year-old male patient who was admitted in our hospital for unintended weight loss, asthenia, and anorexia. Physical examination showed clinical signs of anemia such as pallor of skin and mucous membranes; hemodynamic parameters were normal. Complete blood count (CBC) analysis showed a pancytopenia with anemia, thrombocytopenia, and leukopenia. BM biopsy was performed, showing a malignant infiltration of bone marrow by a metastatic prostate cancer confirmed by immunohistochemistry. Prostate biopsy confirmed the diagnosis of acinar adenocarcinoma with Gleason score 8 (4+4), ISUP grade group 4. Our patient underwent chemical castration using LH-RH analogs in association with second-line hormone therapy by abiraterone acetate. The evolution was good on both the oncological and hematological levels