Robotic lobectomy: tips, pitfalls and troubleshooting

The robotic approach in thoracic surgery has rapidly gained popularity in recent years. As with the introduction of any new technology, this warrants not only adaptation of the operative technique itself, but also the evolution of appropriate troubleshooting strategies. A selected number of helpful tips and technical procedural manoeuvres have been compiled to prevent intraoperative problems, as well as to overcome challenging situations that can arise during robotic lobectomies. In robotic surgery, as opposed to open surgery or video-assisted thoracic surgery, these tips serve an important purpose for the operating surgeon, as well as the entire surgical team involved in the procedure. All the assembled recommendations have proved their effectiveness and have been successfully used by the authors in many procedures. Furthermore, these manoeuvres have been found to be of great importance in the training and proctoring of thoracic surgeons, fellows and residents (bed-side assistants). This guide of clearly arranged tips and troubleshooting strategies offers surgeons a useful tool to overcome difficult situations in robotic lobectomy and preferably improve the reproducibility and safety of their procedures.

Deformation Studies of Tungsten-Gold Contacts at the Nanometer Scale.

The deformation behavior of atomically clean, nanometer sized tungsten / gold contacts was studied at room temperature in ultra-high vacuum. An instrument that combines atomic force microscopy (AFM), scanning tunneling microscopy (STM), and field ion microscopy (FIM) into a single experimental apparatus was designed, constructed, and calibrated. A cross-hair force sensor having a spring constant of - 442 N/m was developed and its motion was monitored during indentation experiments with a differential interferometer. Tungsten tips of controlled size (12.8 nm < tip radius < 2 1.6 nm) were first shaped and characterized using FIM and then indented into a Au (1 10) single crystal to depths ranging from 1.5 nrn to 18 nm using the force sensor. Continuum mechanics models were found to be valid in predicting elastic deformation during initial contact and plastic zone depths despite our small size regime. Multiple discrete yielding events lasting < 1.5 ms were observed during the plastic deformation regime; at the yield points a maximum value for the principal shear stress was measured to be 5 + 1 GPa. During tip withdrawal, "pop-out" events relating to material relaxation within the contact were observed. Adhesion between the tip and sample led to experimental signatures that suggest neck formation prior to the break of contact. STM images of indentation holes revealed various shapes that can be attributed to the (1 1 1 ) (1 10) crystallographic slip system in gold. FIM images of the tip after indentation showed no evidence of tip damage

Curvature and velocity of methane-air Bunsen flame tips.

PIV and photographic recording are used to measure the velocity of the fresh gas and the shape of the reaction layer in a region around the tip of a methane-air Bunsen flame attached to a cylindrical burner. The results compare well with numerical simulations carried out with an infinite activation energy reaction model. The experimental and numerical results confirm that the well-known linear relation between flame velocity and flame stretch derived from asymptotic theory for weakly curved and strained flames is valid for small and moderate values of the flame stretch if the modified definition of stretch introduced by Echekki and Mungal (Proc Combust Inst 23:455–461, 1990) and Poinsot et al. (Combust Sci Technol 81:45–73, 1992) is used. However, the relation between flame velocity and modified stretch ceases to be linear and approaches a square root law for large values of the stretch, when the curvature of the flame tip becomes large compared to the inverse of the thickness of a planar flame.

Curvature and velocity of methane-air Bunsen flame tips

PIV and photographic recording are used to measure the velocity of the fresh gas and the shape of the reaction layer in a region around the tip of a methane- air Bunsen flame attached to a cylindrical burner. The results compare well with numerical simulations carried out with an infinite activation energy reaction model. The experimental and numerical results confirm that the well-known linear relation between flame velocity and flame stretch derived from asymptotic theory for weakly curved and strained flames is valid for small and moderate values of the flame stretch if the modified definition of stretch introduced by Echekki and Mungal (Proc Combust Inst 23:455–461,1990) and Poinsot et al. (Combust Sci Technol 81:45–73,1992) is used. However, the relation between flame velocity and modified stretch ceases to be linear and approaches a square root law for large values of the stretch, when the curvature of the flame tip becomes large compared to the inverse of the thickness of a planar flame

Glassy State and Cryopreservation of Mint Shoot Tips

Vitrification refers to the physical process by which a liquid supercools to very low tem- peratures and finally solidifies into a metastable glass, without undergoing crystallization at a practical cooling rate. Thus, vitrification is an effective freeze-avoidance mechanism and living tissue cryopreservation is, in most cases, relying on it. As a glass is exceedingly vis- cous and stops all chemical reactions that require molecular diffusion, its formation leads to metabolic inactivity and stability over time. To investigate glassy state in cryopreserved plant material, mint shoot tips were submitted to the different stages of a frequently used cryopreservation protocol (droplet-vitrification) and evaluated for water content reduction and sucrose content, as determined by ion chromatography, frozen water fraction and glass transitions occurrence by differential scanning calorimetry, and investigated by low-tempera- ture scanning electron microscopy, as a way to ascertain if their cellular content was vitri- fied. Results show how tissues at intermediate treatment steps develop ice crystals during liquid nitrogen cooling, while specimens whose treatment was completed become vitrified, with no evidence of ice formation. The agreement between calorimetric and microscopic observations was perfect. Besides finding a higher sucrose concentration in tissues at the more advanced protocol steps, this level was also higher in plants precultured at 25/21?C than in plants cultivated at 25?C.

Tips and tricks about financial ratios: how to anticipate unpleasant surprises

Following recent accounting and ethical scandals within the Telecom Industry like Gowex case, old cards are laid on the table: what kind of management and control are we doing on our businesses and what use do we give to the specific tools we have at our disposition? There are indicators, that on a very specific, concise and accurate manner, aside from brief, allow us to analyze and capture the complexity of a business and also they constitute an important support when making optimal decisions. These instruments or indicators show, a priori, all relevant data from a purely economic perspective, while there also exist, the possibility of including factors that are not of this nature strictly. For instance, there are indicators that take into account the customer?s satisfaction, the corporate reputation among others. Both kind of performance indicators form, together, an integral dashboard while the pure economic side of it could be considered as a basic dashboard. Based on DuPont?s methodology, we will be able to calculate the ROI (Return on Investment) of a company from the disaggregation of very useful and much needed indicators like the ROE (Return on Equity) or the ROA (Return on Assets); thereby, we will be able to get to know, to control and, hence, to optimize the company?s leverage level, its liquidity ratio or its solvency ratio, among others; as well as the yield we will be able to obtain if our decisions and management are optimal related to the bodies of assets. Bear in mind and make the most of the abovementioned management tools and indicators that we have at our disposition, allow us to act knowing our path and taking full responsibility, as well as, to obtain the maximum planned benefits, instead of leaving them to be casual. We will be able to avoid errors that can lead the company to an unfortunate and non-desirable situation and, of course, we will detect, way in advance, the actual needs of the business in terms of accounting and financial sanitation before irreversible situations are reached.