Map of natural stones from Sardinia

The poster shows a collection of natural stones quarried for ornamental purposes in Sardinia (Italy) over the last fifty years. Its user-friendly map has been graded to school students level and can be used as a reference in public libraries. There are no previous publications showing a similarly wide range of Sardinian stones. The poster offers scientific information about lithology, quarrying sites, dimension stone producing areas, quarries of historical and/or archaeological interest, historical trend in quarries output, technical properties, stone surface workability and a glossar

Carta delle rocce ornamentali della Sardegna

The poster shows a collection of decorative stones extracted over the last fifty years in Sardinia. The term decorative stone is used generically to refer to all natural stones that can be used as decorative material, mainly for cladding and covering and secondarily in a structural role. The term ornamental stone is also used. The international industry term is dimension stones. Reflecting multiple geological events, the lithological Sardinian landscape has offered and still offers a remarkably wide range of possibilities for researching and gathering decorative stones, according to varying requirements, the main being chromaticism and workability, not forgetting other important characteristics such as hardness and durability. The survey in the Regional Plan of Mining Activities (Piano Regionale delle Attività Estrattive - P.R.A.E.) for the Autonomous Region of Sardinia (Regional Law 30/89) identified eight “Dimension stone producing areas”, each of which features quarries for petrographically homogeneous rock types: granite (4), limestone (1), volcanic rocks (2, basalt and ignimbrites), metamorphic rocks (1

Posterior lumbar interbody fusion with peek cages: personal experience with 20 patients.

AIM: The use of interbody cages to obtain fusion in the lumbar spine has increased noticeably in the last few years. They are used both with and without posterior stabilization. In our institution a prospective analysis to determine whether PEEK cages can be used as a stand alone device has been performed. METHODS: The 20 patients with PEEK cages had clinical and radiological follow-up with controls at 1, 3, 6 and 9 months. RESULTS: The clinical results were considered satisfactory in 75% of the cases. There were no intra-or perioperative complications. There was no displacement of the cages. No signs of unsuccessful fusion were observed. CONCLUSIONS: Interbody PEEK cages fulfill the objective of stabilizing the treated segment immediately and subsequently. They can be used as stand alone devices with the correct surgical technique and following precise indications

Microwave resonant cavity as a reactor for the enzymatic hydrolysis of sucrose

We present here the design and analysis of a microwave resonant cavity to evaluate the effect of RF electromagnetic field on enzyme reactions. The cavity has been first designed using CST. Then, its behaviour in the actual use has been evaluated using the COMSOL multiphysics

Design and optimization of a microwave irradiated and resonant continuous biochemical reactor

The design of a microwave irradiated enzyme (biochemical) reactor is here presented. It consists of a suitable higher-order mode resonant cavity which contains several tubes where the solution containing reagents and products flow in the laminar flow regime. The process evolution under irradiation has then been simulated using the COMSOL multiphysics environment. As an example, the enzymatic hydrolysis reaction of sucrose has been considered. The results of the multiphysics simulation show that such a reactor can be used to effectively perform the reaction process in the optimal conditions for maximizing the reaction rate and preventing the enzyme deactivation by a precise knowledge of the temperature distribution and its strict control

A one-session circumferential reconstruction in thoracic and lumbar spine fractures using a small expandable cage

Aim. Circumferential reconstruction of thoracic and lumbar vertebrae is most frequently performed in two sessions. The authors assessed feasibility, safety and results of a surgical technique in which the use of a small cage allows a less invasive strategy. In addition, since the authors perform urgent decompression in specific cases of spinal cord injury, feasibility of this technique in emergency was verified. Methods. In two Neurosurgical Departments, between May 2001 and May 2006, 62 patients with thoracic or lumbar fractures were operated on using this technique. X-rays were performed postoperatively and around 45 days from surgery. Three-dimension-computed tomography (3D-CT) scans were performed at 3, 6 and 12 months. Neurological evaluations were repeated at every outpatient visit. After screw insertion at the adjacent levels and traditional transpedicular circumferential decompression, further bone is removed to excavate a niche in the vertebral body and the contiguous discs are removed. The expandable cage, filled with bone fragments, is inserted horizontal or oblique laterally to the sac and applied vertical inside that niche and then expanded. The circumferential stabilization is completed with bone grafting and posterior instrumentation. Results. 3D-CT scans showed sound fusion and no manifest correction loss. Nineteen patients improved at least one grade in the ASIA scale and 11 gained neuromeric levels. Conclusion. This technique, fairly undemanding and feasible also in emergency, proved to be safe and resistant. Two-year follow-up demonstrated thriving fusion and steady alignment. It is a valuable surgical therapy to selected cases of burst fracture

Evaluation of Rhodotorula spp. contamination in hospital environments

Microbiological monitoring of air and surfaces is a valuable tool for assessing the level of environmental contamination by bacteria and fungi in hospitals, especially in high-risk wards. The presence of these microorganisms requires strict control in view of their role as opportunistic pathogens. As regard yeasts, Candida albicans is one of the main opportunistic pathogens. However, in recent years, many other “non-Albicans” species have been identified that are implicated in the onset of both localised infections in immunocompetent patients and systemic infections in immunocompromised patients. The aim of the work was to evaluate the frequency of isolation of Rhodotorula spp. in environmental samples of hospital origin in order to highlight how its presence may represent an increased risk for hospitalised patients. The samples were taken in at-risk wards, divided into six types of environments, in three hospitals in southern Sardinia between 2016 and 2019. The presence of moulds and yeasts was higher in the air (55.7%) than on surfaces (44.3%) in the hospital environments (p < 0.001). Similarly, the isolation frequency of Rhodotorula spp. was found to be greater (p < 0.001) in the air (14.2%) than on surfaces (9.2%). This study made it possible to evaluate the presence of pathogenic fungi in hospital environments, paying particular attention to Rhodotorula spp. since it is an emerging opportunistic yeast. It also highlights the importance of control measures especially in those where immunocompromised patients are present

Optimization of Brilliant Blue R photocatalytic degradation by silver nanoparticles synthesized using Chlorella vulgaris

: Synthesis of silver nanoparticles (Ag NPs) using microalgae is gaining recognition for its environmentally friendly and cost-effective nature while maintaining high activity of NPs. In the present study, Ag NPs were synthesized using a methanolic extract of Chlorella vulgaris and subjected to calcination. The X-ray diffraction (XRD) analysis showed a crystalline nature of the products with Ag2O and Ag phases with an average crystalline size of 16.07 nm before calcination and an Ag phase with 24.61 nm crystalline size after calcination. Fourier transform infrared spectroscopy (FTIR) revealed the capping functional groups on Ag NPs, while scanning electron microscopy (SEM) displayed their irregular morphology and agglomeration after calcination. The organic coating was examined by energy-dispersive X-ray spectroscopy (EDX) and thermogravimetric (TGA) analyses, confirming the involvement of the metabolites. The UV-Vis analysis showed a difference in optical properties due to calcination. Synthesized Ag NPs were applied for the photodegradation of hazardous dye Brilliant Blue R in visible light. Different values of light intensity, catalyst dose, initial dye concentration, and pH were tested to identify the optimal set of operating conditions. The highest degradation efficiency of 90.6% with an apparent rate constant of 0.04402 min-1 was achieved after 90 min of irradiation in the highest tested catalyst dosage