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The accurate localization of small tumors of the digestive tract is of paramount importance in surgical oncology because it dictates the limits of resection and the extent of lymph node dissection. In this view, we have designed and fabricated a highly efficient sensing laparoscopic instrument focused on precise non-invasive extralumenal intraoperative detection of small colorectal or gastric tumors. The equipment is fully adapted for laparoscopic surgery and consists of an inductive proximity sensor encapsulated into a watertight stainless-steel case that is connected to an electronic functional block dimensionally scaled-down by the desired form and size for optimal surgical manipulation. The sensor-case unit and the electronic block are coupled together using a modular system which allows disconnection of the latter and sterilization by autoclavation of the former, followed by swift plugging of the electronic block just before surgery in a sterile-controlled environment. The instrument works in tandem with a modified endoscopic hemostatic clip which is attached endoscopically, before surgery, in the mucosa proximal and distal to the tumor. By scanning the serosal side of the digestive organ during the laparoscopic surgical procedure, the detector senses the modified clip and thus pinpoints to the location of the tumor. Additional engineering of the standard endoscopic hemostatic clips by coating them with various combinations of metallic alloys of Cu and Zn was necessary to improve the detection range and sensitivity without compromising on their functionality. The clips were also covered with nanometric layers of Au to ensure their biocompatibility. The ex-vivo dry-lab experiments showed a satisfactory detection distance which was later confirmed in ex-vivo wet-lab experiments on animal organs and human surgical specimens.

This work explore the fabrication of two distinct metallic grid architectures of positive electrode, namely hexagonal and leaf shapes, within the aim of improving the economic and the qualitative electrical performance aspects of lead-acid batteries in the automotive industry. By following a well-established aging procedure, Electrochemical Impedance Spectroscopy has been employed for their characterization by using different grid-acidic electrolyte interface changes. Two particular, parameters were investigated in order to predict the evolution of batteries lifetime performance: the resonance frequency single parameter, and time-dependent analysis of Constant Phase Element at 75 % State of Charge. Single resonance frequency fluctuations have been monitored at each PEIS step, in which we plotted the imaginary part of the impedance as function of frequency. An performance of battery lifetime has resulted for leaf battery than for hexagonal model, by comparison of the exponential-like increment degradation curve vs cycle number at SoC = 100 %. By using the effect of Q1linear decay in the equivalent Randle circuit at 75 % SoC, we obtained for both models a smooth trend of the linear decay slopes, in particular in the second part of their lifetime, in agreement with previous investigated cells, demonstrating that is a robust feature, present in all fabricated cells. A fitting linear regression analysis depending on cycle number was applied to both batteries, in order to highlight the degradation grade of these curves. Another linear fit calibration of the degradation speed was applied for the second sector of batteries lifetime, pointing out a positive correction for the Q1linear decay with ∼30 % for leaf cell over the hexagonal model, but less than previous investigated rectangular models or the industrial type. This suggests that the current homogeneity on the rectangular models during the charge-discharge processes is better distributed in the lower and upper parts of the plates than for hexagonal or leaf electrodes, being spotted here by the effect of current uniformity on their Randle circuit. The homogeneity of the electric field is not ensured by the shape of individual sectors, rather by their size and orientation.

The binding effects of Mn2+and Ca2+ions on the vibrational properties of adenine–thymine (AT) base pairs have been investigated using density functional theory. The metallic atoms were coordinated to N3 and N7 atoms of adenine, respectively. We analyze the geometric properties of different metal–AT base pairs structures, as well as the vibrational bands that can be used to detect the presence of metallic ions. In particular we have found that strong vibrational amplitudes of metallic atoms are expected for the vibrational bands in the range between 400–500 cm−1. Also, we point out the effects of cations binding over a series of selected modes, corresponding to experimental data, providing values for the resulting shifts for each of these vibrational bands.

The low-energy spectroscopies of Mn(II) and Mn(III) porphyrin (P) complexes were investigated using complete active space and subsequent perturbative treatment (CASPT2) as well as DFT-based calculations. Starting from DFT optimizations of MnIIP and MnIIIPCl using crystallographic data, the CASPT2 results show that whatever the relative position of the Mn(II) ion with respect to the porphyrin cavity, the high-spin state S= 5/2 of the [MnP] unit lies much lower in energy than the intermediate S= 3/2 state. Not only are these results in agreement with experimental observations but they also differ from previous theoretical conclusions. In the Mn(III) complexes, σ and π charge redistributions compete to result in a S= 2 ground state. The performances of different functionals have been tested in the reproduction of the CASPT2 spin gaps. Our results confirm that the Mn(II) system is very challenging, as GGA functionals fail in the spin states ordering and in the reproduction of the gaps, unless a high percentage of exact HF exchange (55%), as in KMLYP, is incorporated. This inspection demonstrates the need for specific active space functional to investigate the low-energy spectroscopy of [MnP] units.

•The EIS data are used to perform a qualitative analysis of the lead-acid battery SOH.•Controlled aging of the battery was made in order to find a correlation based on resonance frequency parameter.•Impedance plots vs frequency shifting diagrams emphasize an accurate prediction tool for SOH.•For cells produced under controlled conditions, we get a larger lifetime.•An inferior degradation speed to the cells manufactured in laboratory was resulted.