Gourmet Table Salts: The Mineral Composition Showdown.

Table salts with their specialty flake size, textures, flavors, and colors can be considered a gastronomy niche food already increasing in demand worldwide. Being unrefined, they can contain trace elements potentially both healthy and toxic. In this study, 12 mineral elements (Al, Ca, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, and Zn) in 10 different salts commercially available in southern Italy namely, Atlantic grey, Baule volante, Guerande, Hawaiian pink, Hawaiian black, Himalayan pink, Maldon, Mozia, Persian blue, and smoked salts were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and thermal decomposition amalgamation-atomic absorption spectrophotometry (TDA-AAS). The concentration of mineral elements was variable according to the type of salt and its geographical origin. Co, Cr, Cu, Hg, Pb, and Se levels were tolerable and Al, Ca, Fe, Mn, Ni, and Zn ranged significantly among the samples. Persian Blue and Atlantic Grey salts showed elevated levels of Fe and Zn; their intake can be helpful in some specific conditions. Nevertheless, Ni levels were high in Persian Blue and Smoked salts. Pb exceeded the maximum level in all samples. Additional monitoring analyses of mineral contents in table salts are recommended for human health.

Experimental measurement of forces during percutaneous dilatational tracheostomy.

The measurement of mechanical effects associated with the dilatation phase of a percutaneous dilatational tracheostomy is of primary importance to identify the causes of major complications associated with this procedure, such as tracheal cartilage subluxation or fracture and bleeding. Such information can be very useful also for the design of better instruments and procedures. The aim of this study was to present a methodology to evaluate mechanical effects of the dilatation phase of a percutaneous dilatational tracheostomy on the tracheal rings and adjacent anatomical structures. Forces and moments were measured through a dilator instrumented with strain gauges. Two surgeons, with different levels of expertise, performed the percutaneous dilatational tracheostomy on a lifelike reproduction of an adult head, specifically designed for training professionals. The modified dilator was effective in measuring forces involved in the percutaneous dilatational tracheostomy without affecting the ability of the operator to perform the procedure. The main contribution to the insertion of the dilator was given by the axial force, defined as the force acting on the handle, compressing it (mean and peak force: 48.8 and 88.2 N for Surgeon 1, 31.3 and 82.8 N for Surgeon 2, respectively). The proposed method was effective in measuring differences between procedures performed by surgeons with different amounts of experience in terms of duration, forces applied and repeatability. In addition, it may have applications for use as a feedback for incorrect positioning or excessively variable pressure during the training of surgeons for the execution of percutaneous dilatational tracheostomy.

Investigation into the elastic properties of ex vivo porcine corneas subjected to inflation test after cross-linking treatment.

BACKGROUND: The aim of this work was to evaluate the effect of cross-linking (CXL) on ex vivo porcine corneal elastic properties, using an inflation procedure. METHODS: Twelve corneas were subjected to standard CXL (370 nm, 3 mW/cm2, 30 minutes), while 12 were used as controls. Corneal thickness was measured by Visante optical coherence tomography, before and immediately after treatment, and before inflation test. Both intraocular pressure and radial apical cornea displacement were measured during inflation. Stress-strain curves were obtained by applying the linear shell theory. The elastic modulus was evaluated by calculating the slope of the stress-strain curves. RESULTS: Results showed a statistically significant increase in elastic modulus (p<0.0001), with a mean of 3,868 ± 502 kPa for cross-linked corneas and 2,727 ± 238 kPa for untreated corneas, when subjected to high pressure (40-60 kPa). CXL significantly increased porcine cornea stiffness by about 42%. Findings did not show any significant difference within the physiological range of pressure (2-4 kPa). CONCLUSIONS: The inflation test has been proven to be a valuable tool for the investigation of corneal biomechanics, maintaining both integrity and geometry of corneal tissue.

Investigations on the viscoelastic behaviour of a human healthy heel pad: in vivo compression tests and numerical analysis.

The aim of this study was to investigate the viscoelastic behaviour of the human heel pad by comparing the stress-relaxation curves obtained from a compression device used on an in vivo heel pad with those obtained from a three-dimensional computer-based subject-specific heel pad model subjected to external compression. The three-dimensional model was based on the anatomy revealed by magnetic resonance imaging of a 31-year-old healthy female. The calcaneal fat pad tissue was described with a viscohyperelastic model, while a fibre-reinforced hyperelastic model was formulated for the skin. All numerical analyses were performed to interpret the mechanical response of heel tissues, with loading conditions and displacement rate in agreement with experimental tests. The heel tissues showed a non-linear, viscoelastic behaviour described by characteristic hysteretic curves, stress-relaxation and viscous recovery phenomena. The reliability of the investigations was validated by the interpretation of the mechanical response of heel tissues under the application of three pistons with diameter of 15, 20 and 40 mm, at the same displacement rate of about 1.7 mm/s. The maximum and minimum relative errors were found to be less than 0.95 and 0.064, respectively.

Resistance to wear of four matrices with ball attachments for implant overdentures: a fatigue study.

PURPOSE: The study evaluated in vitro the retention force and the wear resistance over simulated function of four matrix components of ball attachments for implant-retained overdentures. MATERIALS AND METHODS: Four types of matrices for ball attachments were evaluated in a fatigue study simulating 5500 cycles of insertion and removal. The matrices used were (1) a Teflon matrix supported by a metal housing, (2) a titanium matrix, (3) a gold alloy matrix, (4) an O-ring matrix using the red color ring for medium retention. Dimensional changes of the ball attachments were investigated with a profilometer. RESULTS: The Teflon matrices showed an increase of 27% in retention at 5500 cycles while the gold alloy matrices showed an increase of 50% in retention in the first 500 cycles and remained relatively stable up to 5500 cycles. On the other hand, titanium matrices and O-ring matrices exhibited progressive loss of retention ending with 68% and 75% of retention loss, respectively, at 5500 cycles. Dimensional analysis by profilometer revealed significant wear on the ball attachment only for titanium matrixes. CONCLUSIONS: Gold alloy and Teflon matrices showed the highest retention values without retention loss after 3 years of simulated function. Titanium and O-ring matrices presented a continuous loss of retention with the highest wear on the ball attachments when combined with the titanium matrix.