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Non-centrosymmetric superconductors have recently received significant interest due to their intriguing physical properties such as multigap and nodal superconductivity, helical vortex states, as well as non-trivial topological effects. Moreover, large values of the upper critical magnetic field have been reported in these materials. Here, we focus on the study of the temperature dependence of the perpendicular magnetic field of NbRe and NbReN films patterned in micrometric strips. The experimental data are studied within the Werthamer-Helfand-Hohenberg theory, which considers both orbital and Zeeman pair breaking. The analysis of the results shows different behavior for the two materials with a Pauli contribution relevant only in the case of NbReN., (Copyright © 2023, Makhdoumi Kakhaki et al.)

Non-covalent π-π and dipolar interactions with small aromatic molecules have been widely demonstrated to be a valid option to tune graphene work functions without adding extrinsic scattering centers for charge carriers. In this work, we investigated the interaction between a CVD-graphene monolayer and a thermally evaporated sub-monolayer and the following few-layer thin films of similar perylene diimide derivatives: PDI8-CN2 and PDIF-CN2. The molecular influence on the graphene work function was estimated by XPS and UPS analysis and by investigating the surface potentials via scanning Kelvin probe force microscopy. The perfluorinated decoration and the steric interaction in the early stages of the film growth determined a positive work function shift as high as 0.7 eV in the case of PDIF-CN2, with respect to the value of 4.41 eV for the intrinsic graphene. Our results unambiguously highlight the absence of valence band shifts in the UPS analysis, indicating the prevalence of dipolar interactions between the graphene surface and the organic species enhanced by the presence of the fluorine-enriched moieties.

Three novel diketopyrrolopyrrole (DPP) based small molecules have been synthesized and characterized in terms of their chemical-physical, electrochemical and electrical properties. All the molecules consist of a central DPP electron acceptor core symmetrically functionalized with donor bi-thienyl moieties and flanked in the terminal positions by three different auxiliary electron-acceptor groups. This kind of molecular structure, characterized by an alternation of electron acceptor and donor groups, was purposely designed to provide a significant absorption at the longer wavelengths of the visible spectrum: when analysed as thin films, in fact, the dyes absorb well over 800 nm and exhibit a narrow optical bandgap down to 1.28 eV. A detailed DFT analysis provides useful information on the electronic structure of the dyes and on the features of the main optical transitions. Organic field-effect transistors (OFETs) have been fabricated by depositing the DPP dyes as active layers from solution: the different end-functionalization of the dyes had an effect on the charge-transport properties with two of the dyes acting as n-type semiconductors (electron mobility up to 4.4 ⋅ 10 -2  cm 2 /V ⋅ s) and the third one as a p-type semiconductor (hole mobility up to 2.3 ⋅ 10 -3  cm 2 /V ⋅ s). Interestingly, well-balanced ambipolar transistors were achieved by blending the most performant n-type and p-type dyes with hole and electron mobility in the order of 10 -3  cm 2 /V ⋅ s., (© 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Homocysteine (Hcy) is a non-protein, sulfur-containing amino acid, which is recognized as a possible risk factor for coronary artery and other pathologies when its levels in the blood exceed the normal range of between 5 and 12 μmol/L (hyperhomocysteinemia). At present, standard procedures in laboratory medicine, such as high-performance liquid chromatography (HPLC), are commonly employed for the quantitation of total Hcy (tHcy), i.e., the sum of the protein-bound (oxidized) and free (homocystine plus reduced Hcy) forms, in biological fluids (particularly, serum or plasma). Here, the response of Aerosol Jet-printed organic electrochemical transistors (OECTs), in the presence of either reduced (free) and oxidized Hcy-based solutions, was analyzed. Two different experimental protocols were followed to this end: the former consisting of gold (Au) electrodes' biothiol-induced thiolation, while the latter simply used bare platinum (Pt) electrodes. Electrochemical impedance spectroscopy (EIS) analysis was performed both to validate the gold thiolation protocol and to gain insights into the reduced Hcy sensing mechanism by the Au-gated OECTs, which provided a final limit of detection (LoD) of 80 nM. For the OECT response based on Platinum gate electrodes, on the other hand, a LoD of 180 nM was found in the presence of albumin-bound Hcy, with this being the most abundant oxidized Hcy-form (i.e., the protein-bound form) in physiological fluids. Despite the lack of any biochemical functionalization supporting the response selectivity, the findings discussed in this work highlight the potential role of OECT in the development of low-cost point-of-care (POC) electronic platforms that are suitable for the evaluation, in humans, of Hcy levels within the physiological range and in cases of hyperhomocysteinemia.

Electronic devices relying on the combination of different conjugated organic materials are considerably appealing for their potential use in many applications such as photovoltaics, light emission, and digital/analog circuitry. In this study, the electrical response of field-effect transistors achieved through the evaporation of picene and PDIF-CN 2 molecules, two well-known organic semiconductors with remarkable charge transport properties, was investigated. With the main goal to get a balanced ambipolar response, various device configurations bearing double-layer, triple-layer, and codeposited active channels were analyzed. The most suitable choices for the layer deposition processes, the related characteristic parameters, and the electrode position were identified to this purpose. In this way, ambipolar organic field-effect transistors exhibiting balanced mobility values exceeding 0.1 cm 2 V -1 s -1 for both electrons and holes were obtained. These experimental results highlight also how the combination between picene and PDIF-CN 2 layers allows tuning the threshold voltages of the p-type response. Scanning Kelvin probe microscopy (SKPM) images acquired on picene/PDIF-CN 2 heterojunctions suggest the presence of an interface dipole between the two organic layers. This feature is related to the partial accumulation of space charge at the interface being enhanced when the electrons are depleted in the underlayer.

We discuss the formation and post-deposition instability of nanodrop-like structures in thin films of PDIF-CN2 (a perylene derivative) deposited via supersonic molecular beam deposition technique on highly hydrophobic substrates at room temperature. The role of the deposition rate on the characteristic lengths of the organic nanodrops has been investigated by a systematic analysis of atomic force microscope images of the thin films and through the use of the height-height correlation function. The nanodrops appear to be a metastable configuration for the freshly-deposited films. For this reason, post-deposition wetting effect has been examined with unprecedented accuracy throughout a year of experimental observations. The observed time scales, from few hours to months, are related to the growth rate, and characterize the thin films morphological reordering from three-dimensional nanodrops to a well-connected terraced film. While the interplay between adhesion and cohesion energies favors the formation of 3D-mounted structures during the growth, wetting phenomenon following the switching off of the molecular flux is found to be driven by an instability. A slow rate downhill process survives at the molecular flux shutdown and it is accompanied and maybe favored by the formation of a precursor layer composed of more lying molecules. These results are supported by simulations based on a non-linear stochastic model. The instability has been simulated, for both the growth and the post-growth evolution. To better reproduce the experimental data it is needed to introduce a surface equalizer term characterized by a relaxation time taking into account the presence of a local mechanism of molecular correlation.

The authors report a case of severe spontaneous hemorrhage in a patient who underwent surgical repair of an upper umbilical ventral hernia with placement of a polypropylene mesh. On the third postoperative day the patient experienced bleeding in the properitoneal space (above and below the mesh), which spread up to and along the retroperitoneal area, causing severe hypovolemic shock. Postoperative investigations finally identified a virus as the cause of the complication.

A borderline Schwann cell tumour with common bile duct compression and jaundice is extremely rare. This paper presents the first report in the Italian literature of a hepatojejunostomy for a symptomatic lesion midway between benign and malignant.

The authors report their experience in the management of patients with Mirizzi Syndrome (MS) admitted, over a period of 15 years, at the General Surgery of Emergency Department of Cardarelli Hospital, Naples, Italy. All patients were admitted and surgically treated in emergency save for one. Out of 12 patients, cholecystectomy was performed in 7 cases. In others 5 patients, with cholecystocholedochal fistula, cholecystectomy with positionig of T-Tube was performed in 4 cases (MS-II); finally, 1 patient with MS type III undewrwent choledochojejunostomy. According to literature, the diagnostic protocol included abdominal ultrasonography and CT scan of the abdomen for all patients; in one case, a cholangio-MRI was performed to clarify the diagnosis. The preoperative diagnosis is essential to reduce risk of iatrogenic injuries. The cholangio-MRI, used to this extent, clarifies the site of obstruction, shows the anatomy of the biliary tree and allows to make all the possible differential diagnoses in order to exclude the presence of biliary tumors before surgery. The intraoperative cholangiography remains mandatory to clarify the anatomy of the biliary tree. In the cases we have treated, ERCP was never performed. We believe that ERCP has limited indications and unsatisfactory outcomes for both diagnosis and treatment of MS. Pathological examination of the fresh-frozen surgical specimens was always performed intraoperatively to exclude the presence of concomitant cancer of the gallbladder. The traditional treatment of patients with MS is surgery, as confirmed by our experience. We perform cholecystectomy for MS type I and cholecystectomy with direct repair of the biliary fistula over aT tube for MS type II. Patients with MS type III usually undergo a tailored operation based on the intraoperative findings, while choledochojejunostomy is mandatory for patients with MS type IV. Laparoscopic surgery is indicated only for MS type I and II. It seems to carry a higher risk for the patient and we do not use this approach in the emergency settings.

The Authors want to present un uncommon case of polytrauma managed with surgical treatment at the Trauma Center of the A. Cardarelli Hospital in Naples. Chest, abdomen, pelvis, and left lower limb have been severely injured. This case is so interesting because of the rareness of some lesions (i.e. diaphragm rupture) and the numerous lesions of internal organs (i.e. lungs, spleen, liver, pancreas, mesenterium) and of the bones (i.e. thigh-bone and pelvis). A very good outcome has been obtained for survival as well as for functionality and quality of life since we have strictly applied the rules for the management of the "complex" polytrauma.

Objective: The authors, thanks to experience obtained in an Unit for the treatment of digestive fistulas, discuss the possibility of a conservative treatment for the anastomotic fistulas., Material and Methods: From 2000 to 2003 were treated thirty-five patients with post-anastomotic gastroenteric fistulas marked according to their localization, way end output (51.5% high, 42.8% moderate and 5.7% low). The treatment is based on an aspiration system, sometimes integrated with an irrigation system. A semi-permeable barrier was created over the fistula by vacuum packing a synthetic, hydrophobic, polymer covered with a self-adherent surgical sheet. This system create a vacuum chamber equipped with a subathmospheric pressures between 262.2 and 337.5 mmHg (350-450 mmbar), integrated with a continuous irrigation using antibiotic solutions or 3% lactic acid., Results: The AA. obtained the resolution in 30 patients (85.7%), 3 patients needs the surgery (8.6%), 2 died, one for sepsis and the other one for malnutrition. The mean time for the closure was 45 days (from 20 to 90). A part of digestive external fistulas goes to spontaneous resolution so comes the idea that the creation of particular condition is the basis of their closure.

The congenital cystic dilatation of the liver and bile ducts (CDB) is a very uncommon disease. It often appears in females and most frequently in paediatric patients. Its etiopathogenesis is not yet completely defined. Its evolution includes, together with several complications, the malignant transformation. The Authors present the outcomes of their experience based on a series of 5 patients observed from 1991 till today. Apart from the rarity of this disease, their series is so interesting because 4 out of 5 are adult patients and the fifth one is over 15. In addition, differentiating from the literature trend, the group included only male patients. Are also discussed the most important aspects referring to nosology, epidemiology, etiopathogenesis, clinical pattern and its evolution of CDB, looking over a wide review too. The Authors extensively examine the diagnostic problems; owing to that the patients were observed in the period 1991-1999 it is necessary to clarify that some imaging methods, i.e. CSTscan and the bile duct MNR, were not yet introduced. The surgical treatment has been investigated as well, developed during its historical evolution until nowadays and our solutions for the 5 cases have been presented and discussed. In their series the Authors haven't ever observed during hospitalisation a malignant transformation.

The authors report their own experience on the treatment of large bowel obstruction caused by a neoplastic stenosis. During a 36-month period 110 operations for emergency large bowel obstructions were performed: 59 (53.6%) underwent primary anastomosis without colostomy (28 right colectomy, 16 left colectomy, 9 sub-total and 6 total colectomy). Total group post-operative mortality was 2.9% as a result of cardio-pulmonary complications. Morbidity was 19.8%, included a 3% of anastomotic leak underwent surgical treatment. Our results suggest that resection and primary anastomosis can be performed with acceptable morbidity and mortality in a high proportion of cases of emergency large bowel obstructions.

The authors describe a case of Bartter's syndrome, a variety of disease in the newborn, and they point out the most specific of the disease symptoms, that is the normal PA in presence of elevated plasma renin activity. So it was necessary to determine the ANP, the values of which, controlled for a period of 18 months, appeared above the normal ones. The authors conclude that this date would better explain the apparently contradictory date of the normotension.

The authors analysed 31 cases of an acute hypertensive glomerulonephritis. The antihypertensive efficacy of two medicines: a vasodilator (dihidralazine) and a diuretic (Furosemide) was underlibed an these patients. Their efficacy was evident not only in the stabilization of P.A. around normal values on three days, but also on the disappearance of signs of on hypertensive encephalopathy whereas these ones were present.

The authors describe a new-born form of Bartter's syndrome treated for about 6 years with Indomethacin in a quantity of 2 mg/Kg/die except short periods, during which it was given triamterene in a quantity of 2 mg/Kg/die. While with the first medicine the growth of height has had an average increase of about 9 cm a year, with the second one there hasn't been any result neither on growth nor on the rest of symptomatology. The A.A. on the base of recent experimental data think that the deficiency of height could be due to a scanty affinity of peripherical receptors and SmC, that could be removed from the provision of Indomethacin.

In thirty-three newborns with anoxic syndrome was valued the renal injury making use of usual parameters of renal function (Blood urea nitrogen, creatinine, FeNa, Clcr) and furthermore the rate of urinary excretion of beta 2-microglobulin, a marker of tubular damage. All the parameters at the beginning of follow-up were altered. Further monitoring of these showed that BUN, creatinine, FeNa, Clcr were normalized in a short time. Differently beta 2-microglobulin was altered up to the end of follow-up in thirty-one newborns; the values were much lower than original. These results show an high incidence of tubular suffering in the ischemic-anoxic syndrome and a tendency to protract in the time.