Fixation

Growth kinetics of Thiobacillus ferrooxidans in batch cultures, containing prills of elementary sulfur as the sole energy source, were studied by measuring the incorporation of radioactive phosphorus in free and adsorbed bacteria. The data obtained indicate an initial exponential growth of the attached bacteria until saturation of the susceptible surface was reached, followed by a linear release of free bacteria due to successive replication of a constant number of adsorbed bacteria. These adsorbed bacteria could continue replication provided the colonized prills were transferred to fresh medium each time the stationary phase was reached. The bacteria released from the prills were unable to multiply, and in the medium employed they lost viability with a half-life of 3.5 days. The spreading of the progeny on the surface was followed by staining the bacteria on the prills with crystal violet; this spreading was not uniform but seemed to proceed through distortions present in the surfa...

Quantitative strength analysis of first metatarsophalangeal joint arthrodesis was performed using two fixation techniques: a small 6-hole plate with an interfragmentary screw or two crossed lag screws. Twelve matched-pair fresh-frozen cadaveric specimens (24 trials) were used for direct comparison of each of the two fixation techniques. All joint surfaces were prepared with power conical reamers utilizing a standard technique. The fixation construct was stressed to failure on each specimen using a computer-integrated materials tester. Fixation stiffness defined as force (load) over displacement and point of ultimate failure was evaluated. The six-hole plate and interfragmentary screw fixation method was a statistically stiff er form of fixation (p > .01) and displayed a greater point of ultimate failure (p > .002) under the laboratory conditions.

Distal radius fracture often presents a metaphyseal void which is more extended in elderly, osteoporotic patients. Bone graft and bone substitutes are reported to be beneficial in maintaining metaphyseal reduction. We performed a prospective study on 52 menopausal, osteoporotic women with unstable intra-articular distal radius fractures to compare the outcome of percutaneous pinning and immobilisation in a cast for 6 weeks with that using injectable calcium phosphate bone cement (Norian Skeletal Repair System, SRS) to supplement pin and screw fixation and immobilisation in a cast for 3 weeks. All patients were reviewed 2 years (range 21-29 months) after surgery. Patients treated with SRS had better functional outcome, restoration of movement and grip strength ( p<0.001). In this group there was 1 mm loss of radial length, 3 degrees loss of radial inclination and 7 degrees loss of palmar tilt. In the control group radial length decreased 3 mm, radial inclination decreased 11 degre...

The use of lateral mass atlas screws is an important technique to achieve fusion and stability at the craniocervical region affected by different pathologies (degenerative, traumatic, inflammatory, neoplastic, or congenital). This paper describes the anatomy and techniques necessary for proper insertion of posterior C1 lateral mass screws, using anatomic dissection and intraoperative pictures. Knowledge of the anatomy and the surgical technique of insertion of C1 lateral mass screws are of paramount importance to have good surgical results.

Introducción: Los traumatismos dentoalveolares en la población pediátrica son frecuentes por lo cual el odontólogo debe estar capacitado para brindarle atención y un oportuno tratamiento. Las lesiones traumáticas pueden ser intencionadas, resultado de traumatismos directos o indirectos. Entre las etiologías predominantes encontramos las caídas, siendo el diente más afectado el incisivo central superior con un 80 %. El objetivo principal es la reposición y estabilización del segmento óseo mediante férulas para limitar su movimiento y permitir la curación del ligamento periodontal y cicatriz ósea. El pronóstico varía de acuerdo a la condición de cierre apical, tipo de traumatismo y el tiempo transcurrido. Se debe valorar de manera constante, clínica y sintomatológica, los cambios de sensibilidad y de coloración. Reporte de caso: En este trabajo se expone el diagnóstico, tratamiento y progreso, de un niño de 8 años de edad que presenta una luxación palatina dentaria de la pieza 1.1, para lo cual se realizó una reducción mecánica y fijación rígida. Conclusión: Aunque el medio de fijación suele presentar alteración a nivel del tejido periodontal se obtuvo una evolución satisfactoria.

RESUME Les techniques histologiques ont pour but l'obtention de coupes fines, colorées de matériels biologiques observables au microscope optique. Le matériel biologique à étudier va subir différents traitements avant de pouvoir être analysé au microscope : fixation, déshydratation, imprégnation, inclusion, coupe et coloration. Le résultat final doit refléter au plus juste l'état natif du prélèvement. Le tissu biologique doit donc être conservé dans un état aussi proche que possible de l'état vivant, tout en le rendant imputrescible. Cette étape de conservation est assurée par des agents fixateurs. Un fixateur modifie les tissus en stabilisant notamment les protéines et les rend ainsi résistants à tout changement. JR. BAKER (1) utilisait souvent cet exemple pour expliquer la fixation : quand une porte est ouverte, sa position peut être changée facilement mais si la porte est ouverte et fixée au sol, cela modifie un peu la porte, de sorte qu'elle est stabilisée et rés...

Death is a central part of Harry Potter’s story and appears in many ways across the seven books. Two different reactions to death, which occur in the years preceding the incidents in the Philosopher’s Stone, precipitate the story itself. The first is Lord Voldemort’s fear of death and preoccupation to overcome it; here, mortality is linked with weakness and living forever is the ultimate form of power. The second is Lily Potter’s sacrifice of herself to save Harry’s life, where her life and love then form a shield to protect Harry; here, death is accepted, not battled with, and carries power that goes beyond dying. In a sense, these are two diametrically opposite ideas about death, which find fruition in the final volumes in the motifs of Horcruxes and Hallows. This paper intends to explore both of these as two entirely different attempts to conquer or destroy death, through an examination of loss, mourning and grief in the Harry Potter books. It is argued in this paper that each book brings Harry back to connect with his parents. Indeed, it is when he is put in touch with his parents’ memories that his journey to Hogwarts and learning about himself begins. This creates to explore grief, a process of healing and growth. In this paper, then, Harry's search for the pieces of Voldemort's soul, the Horcruxes, and his eventual mastery of the three Deathly Hallows, will be connected with his internal journey of grieving the people he loses along the way, starting with his parents. This will also be connected with other key characters and their respective relationships with death

A series of cold brand bisazo reactive dyes (4a–h) were obtained by the coupling of tetrazotised 4,4′-methylene-bis(2-methyl-5-nitro aniline) (2) with various cyanurated coupling components (3a–h) in good yield. Their dyeing performances as reactive dyes have been assessed on silk, wool and cotton fabrics. These dyes were characterized by UV–Vis, FTIR, 1H NMR spectroscopic techniques elemental analysis. The percentage dye bath exhaustion and fixation on different fibers were found to be very good. The dyed fabric showed moderate to very good light fastness and good to excellent washing and rubbing fastness properties. Spectral properties and colorimetric data (L∗, a∗, b∗, C∗, H∗, K/S) have also been studied in detail.

CO 2 at different concentrations were added to cultures of the eukaryotic microalgae, Chlorella kessleri, C. vulgaris and Scenedesmus obliquus, and the prokaryotic cyanobacterium, Spirulina sp., growing in flasks and in a photobioreactor. In each case, ...