Bioinspired Nacre-Like Alumina with a Metallic Nickel Compliant Phase Fabricated by Spark-Plasma Sintering.

Many natural materials present an ideal "recipe" for the development of future damage-tolerant lightweight structural materials. One notable example is the brick-and-mortar structure of nacre, found in mollusk shells, which produces high-toughness, bioinspired ceramics using polymeric mortars as a compliant phase. Theoretical modeling has predicted that use of metallic mortars could lead to even higher damage-tolerance in these materials, although it is difficult to melt-infiltrate metals into ceramic scaffolds as they cannot readily wet ceramics. To avoid this problem, an alternative ("bottom-up") approach to synthesize "nacre-like" ceramics containing a small fraction of nickel mortar is developed. These materials are fabricated using nickel-coated alumina platelets that are aligned using slip-casting and rapidly sintered using spark-plasma sintering. Dewetting of the nickel mortar during sintering is prevented by using NiO-coated as well as Ni-coated platelets. As a result, a "nacre-like" alumina ceramic displaying a resistance-curve toughness up to ≈16 MPa m½ with a flexural strength of ≈300 MPa is produced.

Goniometer evaluation of thoracic kyphosis and lumbar lordosis in subjects during growth age: a validity study.

INTRODUCTION: The aim of the present study is to evaluate the validity of a pocket compass needle goniometer (IncliMed®, University of Padua) to measure the thoracic kyphosis and lumbar lordosis in children and adolescent. MATERIAL AND METHODS: In a group of 128 adolescent the same clinician (FC) measured the thoracic kyphosis and lumbar lordosis according to the goniometer technique and the Cobb angle on lateral spinal radiographs. The linear regression analysis and the Bland and Altman criteria were used for the data analysis. RESULTS: A strong concordance existed between radiological and goniometer evaluation of the thoracic kyphosis (linear regression coefficient: b=0.897;p=0.000), but poor concordance existed at the lumbar lordosis evaluation (b=0.526;p=0.000); so we introduced a modification of the original traditional Cobb method of measurement with improved the linear regression coefficient (b=0.820,p=0.000). CONCLUSIONS: Our results confirm the clinical utility of goniometer assessment for the quantification of thoracic kyphosis and lumbar lordosis in children and adolescent.

RMI study and clinical correlations of ankle retinacula damage and outcomes of ankle sprain.

Recent studies reveal the role of the ankle retinacula in proprioception and functional stability of the ankle, but there is no clear evidence of their role in the outcomes of ankle sprain. 25 patients with outcomes of ankle sprain were evaluated by MRI to analyze possible damage to the ankle retinacula. Patients with damage were subdivided into two groups: group A comprised cases with ankle retinacula damage only, and group B those also with anterior talofibular ligament rupture or bone marrow edema. Both groups were examined by VAS, CRTA and static posturography and underwent three treatments of deep connective tissue massage (Fascial Manipulation technique). All evaluations were repeated after the end of treatment and at 1, 3 and 6 months. At MRI, alteration of at least one of the ankle retinacula was evident in 21 subjects, and a further lesion was also identified in 7 subjects. After treatment, VAS and CRTA evaluations showed a statistically significant decrease in values with respect to those before treatment (p < 0.0001). There were also significant improvements (p < 0.05) in stabilometric platform results. No significant difference was found between groups A and B. The initial benefit was generally maintained at follow-up. The alteration of retinacula at MRI clearly corresponds to the proprioceptive damage revealed by static posturography and clinical examination. Treatment focused on the retinacula may improve clinical outcomes and stabilometric data.

Healthcare service use in adolescents with non-specific musculoskeletal pain.

AIM: To estimate occurrence of non-specific musculoskeletal pain in a wide population sample of Italian adolescents, and to investigate their use of healthcare services (seeking of medical attention, referral for diagnostic tests and treatment use). METHODS: We investigated 7542 high-school adolescents (aged between 12 and 16 years) by a structured questionnaire and consisting of personal data, presence of pain, health provider consulted, referral for diagnostic tests and compliance with the prescribed treatments. RESULTS: In 3399 (45.1%) reported musculoskeletal pain (the most affected sites being the spine and knees), 2525 (74.2%) of whom had sought medical attention. Of the 2525 subjects who had sought healthcare, 1061 (42.0%) had consulted more than one health provider, 2410 (95.4%) had been referred for diagnostic tests, and some form of treatment had been recommended for 2445 (96.8%), but only 1694 (69.2%) had complied with prescribed therapies. The most important factors linked to health seeking behaviour were pain intensity, pain lasting longer than 3 months, injury, interruption to or absence of physical activity and localization in the spine and knee. CONCLUSION: Non-specific musculoskeletal pain is a frequent event in Italian adolescents and that a large number of these subjects consult a healthcare service.

Hump height in idiopathic scoliosis measured using a humpmeter in growing subjects: relationship between the hump height and the Cobb angle and the effect of age on the hump height.

BACKGROUND: The comparison between Cobb angle and hump height measured using a humpmeter in idiopathic scoliosis have produced contradictory findings concerning the association between the two variables in growing subjects. AIM: To analyze the relationship between the hump height and the Cobb angle and the effect of age on the first. DESIGN: Cross-sectional, descriptive analytical study. SETTING: A tertiary university hospital. POPULATION: One thousand two-hundred forty-five subjects with diagnosed idiopathic scoliosis or with a hump without spine deformity, aged between 3-21. METHODS: The hump was measured with subjects in a forward-bending position using a pocket humpmeter; the Cobb angle was determined on a traditional radiograph. A linear regression estimated the Cobb angle in relation to the hump height, and a multiple regression based on standardized regression coefficients (ß) and coefficients of determination (R2) assessed the contribution of age and the Cobb angle to hump variations. RESULTS: The hump height was between 0-50 mm and the Cobb angle was between 0-78°. Based on regression coefficients, every unit (1 mm) increase in the thoracic/thoracolumbar and lumbar humps corresponded to an average increase in the Cobb angle of 1.542° (SE 0.037°; P=0.000) and 1.857° (SE 0.095°; P=0.000), respectively. The 95% confidence intervals for the estimated mean Cobb angles and those for the individual angles with respect to a given hump height lead to various hypotheses regarding the interconnection between the two entities. ß values for age were low with respect to ß values for the Cobb angle both at the thoracic level (0.095 vs. 0.807) and at the lumbar one (0.138 vs. 0.651), and R2, after the age-variable was excluded, decreased slightly from 70.3% to 69.4% and from 48.5% to 46.7%, respectively. CONCLUSIONS: Humpmeter measurements can thus be considered reliable in diagnosed idiopathic scoliosis and in asymmetric children - having a hump without deformity in spine - regardless of age. CLINICAL REHABILITATION IMPACT: Hump severity can be considered the balance needle when children with idiopathic scoliosis and asymmetric children are being treated and/or monitored. The humpmeter technique, coupled with Cobb angle measurement, can facilitate the clinical evaluation.

3D Printing Bioinspired Ceramic Composites.

Natural structural materials like bone and shell have complex, hierarchical architectures designed to control crack propagation and fracture. In modern composites there is a critical trade-off between strength and toughness. Natural structures provide blueprints to overcome this, however this approach introduces another trade-off between fine structural manipulation and manufacturing complex shapes in practical sizes and times. Here we show that robocasting can be used to build ceramic-based composite parts with a range of geometries, possessing microstructures unattainable by other production technologies. This is achieved by manipulating the rheology of ceramic pastes and the shear forces they experience during printing. To demonstrate the versatility of the approach we have fabricated highly mineralized composites with microscopic Bouligand structures that guide crack propagation and twisting in three dimensions, which we have followed using an original in-situ crack opening technique. In this way we can retain strength while enhancing toughness by using strategies taken from crustacean shells.

Goniometric evaluation of the spinal sagittal curves in children and adolescents: A reliability study.

BACKGROUND: Gold standard for spine deformities assessment is X rays, but the procedure bears a risk of exposure. OBJECTIVE: To investigate intra-rater and inter-rater reliability of a pocket compass needle goniometer (IncliMed®, University of Padua) to non-invasively evaluate spine curves in children and adolescents. METHODS: Prospective reliability study in a paediatric population (mean age 12.5 years ± 2.5). Children with spine deformities (Scheuermann's or postural kyphosis, idiopathic scoliosis) and healthy controls were included. Two physician measured spinal curves with the surface goniometer IncliMed® within a temporal range of 10 minutes. Participants were re-tested after a mean of 28 days for the intra-rater study. Agreement limit and coefficient of repeatability were calculated according to the linear regression analysis; the Bland and Altman method was applied to obtain average of differences and standard error of the mean of the differences. RESULTS: One hundred and thirty-nine subjects participated to the inter-rater reliability assessment; 30 to the intra-rater reliability assessment. Inter-observer variability for IncliMed® measurements was ± 11° both for kyphosis and for lordosis. The intra-observer variability for kyphosis and lordosis measurements was ± 11° and ± 12°. CONCLUSIONS: IncliMed® is a reliable, non-invasive tool to screen and monitor spinal curves in paediatric populations.

Using graphene networks to build bioinspired self-monitoring ceramics.

The properties of graphene open new opportunities for the fabrication of composites exhibiting unique structural and functional capabilities. However, to achieve this goal we should build materials with carefully designed architectures. Here, we describe the fabrication of ceramic-graphene composites by combining graphene foams with pre-ceramic polymers and spark plasma sintering. The result is a material containing an interconnected, microscopic network of very thin (20-30 nm), electrically conductive, carbon interfaces. This network generates electrical conductivities up to two orders of magnitude higher than those of other ceramics with similar graphene or carbon nanotube contents and can be used to monitor 'in situ' structural integrity. In addition, it directs crack propagation, promoting stable crack growth and increasing the fracture resistance by an order of magnitude. These results demonstrate that the rational integration of nanomaterials could be a fruitful path towards building composites combining unique mechanical and functional performances.

Ultralight, Strong, Three-Dimensional SiC Structures.

Ultralight and strong three-dimensional (3D) silicon carbide (SiC) structures have been generated by the carbothermal reduction of SiO with a graphene foam (GF). The resulting SiC foams have an average height of 2 mm and density ranging between 9 and 17 mg cm(-3). They are the lightest reported SiC structures. They consist of hollow struts made from ultrathin SiC flakes and long 1D SiC nanowires growing from the trusses, edges, and defect sites between layers. AFM results revealed an average flake thickness of 2-3 nm and lateral size of 2 µm. In-situ compression tests in the scanning electron microscope (SEM) show that, compared with most of the existing lightweight foams, the present 3D SiC exhibited superior compression strengths and significant recovery after compression strains of about 70%.

Ultra-stiff large-area carpets of carbon nanotubes.

Herewith, we report the influence of post-synthesis heat treatment (≤2350 °C and plasma temperatures) on the crystal structure, defect density, purity, alignment and dispersibility of free-standing large-area (several cm(2)) carpets of ultra-long (several mm) vertically aligned multi-wall carbon nanotubes (VA-MWCNTs). VA-MWCNTs were produced in large quantities (20-30 g per batch) using a semi-scaled-up aerosol-assisted chemical vapour deposition (AACVD) setup. Electron and X-ray diffraction showed that the heat treatment at 2350 °C under inert atmosphere purifies, removes residual catalyst particles, and partially aligns adjacent single crystals (crystallites) in polycrystalline MWCNTs. The purification and improvement in the crystallites alignment within the MWCNTs resulted in reduced dispersibility of the VA-MWCNTs in liquid media. High-resolution microscopy revealed that the crystallinity is improved in scales of few tens of nanometres while the point defects remain largely unaffected. The heat treatment also had a marked benefit on the mechanical properties of the carpets. For the first time, we report compression moduli as high as 120 MPa for VA-MWCNT carpets, i.e. an order of magnitude higher than previously reported figures. The application of higher temperatures (arc-discharge plasma, ≥4000 °C) resulted in the formation of a novel graphite-matrix composite reinforced with CVD and arc-discharge-like carbon nanotubes.

S.TR.E.A.M., system for trace element assessment with mosses. An equation to estimate mercury concentration in freshwaters.

Hundred experiments of Hg bioaccumulation with the aquatic moss Rhynchostegium riparioides (Hedw.) C.E.O. Jensen transplanted under laboratory conditions were carried out with the aim of (1) measuring the metal uptake at increasing water concentrations (0.25-128 microg Hg(2+)L(-1)) and increasing exposure time (24-189 h), (2) studying the influence of pH (6.3-8.5) and water concentration of Na (3-114 mg L(-1)), Ca (62-125 mg L(-1)) and Mg (13-54 mg L(-1)) on the metal uptake, (3) achieving a database for mathematical and statistical elaborations, and, (4) producing an equation modelling the uptake. A linear uptake was observed for water concentrations 0.05) in the Hg uptake ratio (0.496x10(5)

Upper limb rehabilitation robotics after stroke: a perspective from the University of Padua, Italy.

Rehabilitation robotics is an emerging research field that aims to employ leading-edge robotic technology and virtual reality systems in the rehabilitation treatment of neuro-logical patients. In post-stroke patients with upper limb impairment, clinical trials have so far shown positive results in terms of motor recovery, but poor efficacy in terms of functional outcome. Much work is needed to develop a new generation of rehabilitation robots and clinical protocols that will be more effective in helping patients to regain their abilities in activities of daily living. This paper presents some key issues in the future perspective of upper limb robotic rehabilitation after stroke.

Robot-aided intensive training in post-stroke recovery.

The successful motor rehabilitation of stroke patients requires an intensive and task-specific therapy approach. The plasticity of the adult human brain provides opportunities to enhance traditional rehabilitation programs for these individuals. Intensive robot-aided sensorimotor training may have a positive effect on reducing impairment and disability and increasing reorganization of the adult brain. This approach may therefore efficaciously complement standard post-stroke multidisciplinary programs as shown by recent experimental trials.