Search results for " shaft"

Failure Analysis of a Humeral Shaft Locking Compression Plate—Surface Investigation and Simulation by Finite Element Method

2019

A case study of a failed humeral shaft locking compression plate is presented, starting with a clinical case where failure occurred and an implant replacement was required. This study uses finite element method (FEM) in order to determine the failure modes for the clinical case. Four loading scenarios that simulate daily life activities were considered for determining the stress distribution in a humeral shaft locking compression plate (LCP). Referring to the simulation results, the failure analysis was performed on the explant. Using fracture surface investigation methods, stereomicroscopy and scanning electron microscopy (SEM), a mixed mode failure was determined. An initial fatigue failu…

Non-Linear Hysteretic Instability in Rotating Machinery

2013

Contribution to the Knowledge of Dermatophytic Invasion of Hair

1970

We have used the scanning electron microscope to investigate the changes that occur in scalp hair during infection with Trichophyton violaceum . We provide information on the morphology of these dermatophytes and present evidence that their hyphae dig tunnel-like burrows into the hair shaft, dissociating hair into keratin fibrils.

NUMERICAL FATIGUE LIFE EVALUATION OF AN INNOVATIVE INTERNAL COMBUSTION ENGINE SHAFT

2011

A novel self-balanced internal combustion engine is presented. The new engine has a modular structure composed of two cylinders arranged in opposite way. It is characterized by an innovative system of linking between the pistons and the shaft, which has three toggles. One of these is on the middle of the shaft, whereas the others two are placed symmetrically. Thanks to this particular shape of the shaft, the pistons can rotate with the same timing and so the new engine comes back to be perfectly auto-balanced. Moreover, the fatigue life prediction of the shaft has been studied through numerical methods. In particular, two different approaches have been compared to estimate the maximum numbe…

Development of antennal sensilla during moulting inNeomysis integer (Leach) (Crustacea, Mysidacea)

1980

The sensilla are associated with 6 enveloping cells. The innermost enveloping cell (e 1) secretes the dendritic sheath (=thecogen cell). All other enveloping cells are involved in the formation of the outer cuticular apparatus in secreting the cuticle of a definite region of the new hair shaft. The development of the new sensilla begins when an exuvial space expands between old cuticle and epithelium. The newly forming hair shafts lie folded back in an invagination of the epidermal tissue. Only a distal shaft part projects into the free exuvial space. The cuticle of the distal and middle shaft region is secreted by the three middle enveloping cells (e 2–e 4) (=trichogen cells), which are ar…

Pili Torti: A Feature of Numerous Congenital and Acquired Conditions

2021

Pili torti is a rare condition characterized by the presence of the hair shaft, which is flattened at irregular intervals and twisted 180° along its long axis. It is a form of hair shaft disorder with increased fragility. The condition is classified into inherited and acquired. Inherited forms may be either isolated or associated with numerous genetic diseases or syndromes (e.g., Menkes disease, Björnstad syndrome, Netherton syndrome, and Bazex-Dupré-Christol syndrome). Moreover, pili torti may be a feature of various ectodermal dysplasias (such as Rapp-Hodgkin syndrome and Ankyloblepharon-ectodermal defects-cleft lip/palate syndrome). Acquired pili torti was described in numerous forms of …

Humeral Shaft Fractures

2014

Humeral shaft fractures account for approximately 7 % of all fractures in adults. They occur after direct trauma such as traffic accidents or after indirect, rotational trauma in sports accidents or falls at home. There are two peaks of incidence in the adult population: the young male and the older female. The first patient typically is the victim of high-energy trauma with multiple lesions, a more severe humeral fracture type and concomitant soft tissue damage. The latter patient suffers a solitary lesion and is the victim of a low-energy accident such as a fall from a standing or sitting position. The fracture type is then simple and there is no or minimal soft tissue damage. As pain is …

La métallurgie du fer au Sahel : Répartition spatiale de bas fourneaux au Sud-Ouest du Niger. Premiers résultats

2010

International audience; A 15 km à l'Est de Niamey (Sud-Ouest du Niger), une prospection pédestre exhaustive a permis de dénombrer plus de 4000 bas-fourneaux sur un bassin versant de 24 km². Ils sont identifiables par la présence de scories correspondant aux résidus de réduction du fer. Ce grand nombre de structures de réduction est lié au fonctionnement à usage unique des bas-fourneaux, qui est peu étudié dans la région ouest africaine. Les premières études de répartition spatiale montrent que l'implantation de ces bas-fourneaux est principalement soumise à la géomorphologie. Les forgerons ont installé leurs sites de réduction à proximité des talus de plateaux où affleure le minerai de fer …

The transformation of a building of the 1970s into a contemporary sustainable building in the Mediterranean Basin

2008

The paper shows the design strategies adopted by a group of graduands of the Faculty of Building Engineering at the University of Palermo involved in a research project aimed to analyse the problems related to the renovation of modern buildings and to solve them by using sustainable approach. In particular, the aim of the research is to investigate these problems in the context of the Mediterranean Basin by adopting, when possible, design criteria inherited by the traditional architecture where sustainable design strategies were used unconsciously. The graduands thesis consists in the transformation of Mazara City Hall into the new "Satiro Danzante Museum" by using natural ventilation syste…