Lithiation Mechanism in High-Entropy Oxides as Anode Materials for Li-Ion Batteries: An Operando XAS Study.

High-entropy oxides based on transition metals, such as Mg0.2Co0.2Ni0.2Cu0.2Zn0.2O (TM-HEO), have recently drawn special attention as potential anodes in lithium-ion batteries due to high specific capacity and cycling reversibility. However, the lithiation/delithiation mechanism of such systems is still controversial and not clearly addressed. Here, we report on an operando XAS investigation into TM-HEO-based anodes for lithium-ion cells during the first lithiation/delithiation cycle. This material showed a high specific capacity exceeding 600 mAh g-1 at 0.1 C and Coulombic efficiency very close to unity. The combination of functional and advanced spectroscopic studies revealed complex charging mechanisms, developing through the reduction of transition-metal (TM) cations, which triggers the conversion reaction below 1.0 V. The conversion is irreversible and incomplete, leading to the final collapse of the HEO rock-salt structure. Other redox processes are therefore discussed and called to account for the observed cycling behavior of the TM-HEO-based anode. Despite the irreversible phenomena, the HEO cubic structure remains intact for ∼60% of lithiation capacity, so proving the beneficial role of the configuration entropy in enhancing the stability of the HEO rock-salt structure during the redox phenomena.

Dye-sensitized photocatalytic hydrogen production: distinct activity in a glucose derivative of a phenothiazine dye.

A thiophene-based donor-acceptor phenothiazine dye has been functionalized with a peripheral glucose unit (PTZ-GLU) to bust its affinity to water and enhance dye-sensitized photogeneration of hydrogen. Compared to the corresponding alkyl derivative (PTZ-ALK), as well as the common hydrophilic triethylene glycol substitution (PTZ-TEG), the sugar derivative shows a lower contact angle; PTZ-GLU performed twice more efficient than PTZ-TEG in the photogeneration of hydrogen in terms of evolved gas and turnover number.

Somatostatin receptor scintigraphy versus chromogranin A assay in the management of patients with neuroendocrine tumors of different types: clinical role.

BACKGROUND: Current diagnosis and staging of neuroendocrine tumors (NETs) are significantly improved by the introduction of the chromogranin A (CgA) assay in plasma or serum as a tumor marker, and by the use of somatostatin receptor scintigraphy (SRS) for tumor localization. However, the clinical role of CgA assay compared with SRS in the management of NETs has not been well elucidated. PATIENTS AND METHODS: Sixty-three consecutive patients with a histological diagnosis of NET underwent plasma CgA assay and SRS for tumor staging (23 cases), evaluation of tumor response (18 cases) and evaluation of tumor recurrence on follow-up (22 cases). Twenty-one patients had well-differentiated neuroendocrine tumors (WDNETs: 18 gastroenteropancreatic tumors and three lung NETs); 22 patients had well-differentiated neuroendocrine carcinomas (WDNECs: 17 gastroenteropancreatic carcinomas, two lung neuroendocrine carcinomas and three neuroendocrine carcinomas of unknown origin) and 20 patients had poorly differentiated neuroendocrine carcinomas (PDNECs: 14 extra-pulmonary small-cell carcinomas and six Merkel cell carcinomas). Almost all (58 of 63) NETs were non-functioning. The quantitative determination of CgA was performed in plasma using an enzyme immunoassay with a cut-off value fixed at 34 U/l. Scintigraphies with indium 111-DTPA-octreotide ((111)In-pentetreotide) included whole-body images and single photon emission computed tomography (SPECT) scans of the chest and abdomen. RESULTS: SRS results were compared with CgA findings and final clinical data. The overall sensitivity of SRS and CgA, based on the final clinical data, was 77% and 55%, respectively, whereas the specificity of both SRS and CgA was 94%. Concerning tumor type, SRS accuracy was 95% for WDNETs, 86% for WDNECs and 60% for PDNECs; CgA accuracy was 76% for WDNETs, 68% for WDNECs and 50% for PDNECs. With regard to disease extent, SRS sensitivity was 100% for limited disease and 72% for advanced disease; CgA sensitivity was 43% for limited disease and 57% for advanced disease. CONCLUSIONS: In our NET series, SRS proved to be more sensitive than CgA, with equivalent specificity. Tumor differentiation influences the sensitivity of SRS and CgA analysis. In addition, the plasma CgA level is related to tumor secretory activity. Nevertheless both SRS and CgA should be considered useful tools in the diagnostic work-up of NET patients.

The use of thallium-201 in the preoperative detection of breast cancer: an adjunct to mammography and ultrasonography.

Thallium-201 breast scans were performed preoperatively in 72 female patients with breast abnormalities detected by mammography and/or ultrasonography (7.5-13 MHz), in order to differentiate benign from malignant breast disease. Informed consent was obtained from each patient. Scintigraphy consisted of anterior and oblique planar images of the affected breast and axilla at 10 min and 3 h following the injection of 201Tl chloride (110 MBq). All 201Tl scans were interpreted without prior knowledge of surgery data. Pathological features of breast malignancies, such as tumour size, axillary lymph node metastases, tumour grading, lymphatic vascular channel invasion and receptor status, were analysed for their association with 201Tl uptake by tumour cells. A total of 76 breast lesions were assessed in the study. On final histological diagnosis, there were 56 malignant tumours, 14 benign nodules (9 fibroadenomas, two cases of adenosis, two cases of focal fibrosis and one case of epitheliosis) and six atypical lesions (atypical ductal or lobular hyperplasia). Thallium scintigraphy was shown to have high accuracy (92%) in detecting breast cancer, better than mammography (74%) and ultrasonography (84%). Almost all (51/56) breast cancers showed greater 201Tl activity than surrounding normal breast tissue while there was no significant increase in 201Tl activity above background in all but one (19/20) case of non-malignant disease. 201Tl activity within breast tumours, calculated as tumour/background (T/B) ratio, ranged between 1.2 and 2.5 with a mean value of 1.45. In our experience the concentration of thallium in the breast cancer seems to be primarily dependent on vascularity and tumour size rather than tumour grading, lymphatic/vascular invasion or receptor status. 201Tl scan sensitivity was 97% for malignant lesions larger than 1.5 cm (n = 35) and 80% for lesions of 1.5 cm or less (n = 21); however, five of the eight breast cancers smaller than 1.0 cm were also detectable by 201Tl scintigraphy, compared with five out of seven by mammography. Thallium scintigraphy would not be useful in evaluating the axilla for lymph node metastases (sensitivity 27%, specificity 77%).

[Case of hemorrhagic pericarditis as the initial manifestation of pulmonary adenocarcinoma]. / Un caso di pericardite emorragica come prima manifestazione di un adenocarcinoma polmonare.

The Authors describe a case of pericardial involvement as the first sign of lung adenocarcinoma. Several evacuatory pericardiocentesis were required to treat recurrent hemorrhagic effusion. Pericardiectomy was finally carried out. The course of pericarditis was rapid: three and half months elapsed from the first symptoms of dyspnea to the death of patient.