1,373 research outputs found
Functional anatomy of pelvic floor.
Generally, descriptions of the pelvic floor are discordant, since its complex structures and the complexity of pathological disorders of such structures; commonly the descriptions are sectorial, concerning muscles, fascial developments, ligaments and so on. On the contrary to understand completely nature and function of the pelvic floor it is necessary to study it in the most unitary view and in the most global aspect, considering embriology, philogenesy, anthropologic development and its multiple activities others than urological, gynaecological and intestinal ones. Recent acquirements succeeded in clarifying many aspects of pelvic floor activity, whose musculature has been investigated through electromyography, sonography, magnetic resonance, histology, histochemistry, molecular research. Utilizing recent research concerning not only urinary and gynecologic aspects but also those regarding statics and dynamics of pelvis and its floor, it is now possible to study this important body part as a unit; that means to consider it in the whole body economy to which maintaining upright position, walking and behavior or physical conduct do not share less than urinary, genital, and intestinal functions. It is today possible to consider the pelvic floor as a musclefascial unit with synergic and antagonistic activity of muscular bundles, among them more or less interlaced, with multiple functions and not only the function of pelvic cup closure
Thermal modelling of a totally enclosed fan-cooled electrical machine
A Totally Enclosed Fan-Cooled (TEFC) low voltage induction motor has been extensively investigated by means of Computational Fluid Dynamics (CFD) in order to look at detailed airflow and heat transfer modelling of such machines.
The typical structure of this machine design, where the heat removal is dependent on both the internal and external features, provides a significant modelling challenge as the internal and external flows and heat transfer must be analysed jointly, creating a complex scenario with multiple dependencies. Local fluid flow and thermal investigations of the most critical regions of the internal and external domains respectively allowed the identification of the best modelling approach and optimal mesh settings in terms of solution accuracy and computational cost.
A new modelling approach for more realistic end windings representation, which potentially can be applied to different kinds of machines, was developed in order to achieve more accurate predictions of complex fluid flow and heat transfer phenomena compared to a simplified representation commonly used. The developed methodology allowed different levels of end windings porosity to be investigated with results showing a significant impact on overall fluid flow and thermal predictions.
A full thermal CFD 3D model of the selected TEFC motor which includes all internal/external fluid and solid domains, in conjunction with electrical/thermal losses distributed across the whole machine, was then developed. The thermal and airflow analysis performed with the CFD conjugate model allowed an accurate understanding and prediction of the overall machine temperature distribution.
Experimental tests were carried out to validate the CFD model developed: temperatures, heat fluxes and torque were measured throughout the tests and data collected were compared to quantities predicted analytically and numerically showing a good agreement with predictions.
The validation of the developed CFD model allowed also to identify opportunities to improve the machine performance; enhanced cooling can lead to significant improvements in terms of reduction of temperature dependent losses and materials lifetime. Alternative design improvements were therefore proposed to enhance the overall TEFC machine performance and they were investigated with the numerical model developed.
Geometrical modifications of the internal original cooling design, consisting of shaft mounted stirrers in the machine’s end region, were considered. The more realistic and detailed end windings representation developed in this work allowed to investigate the impact of higher level of porosity/cavities of the end windings on the overall machine thermal perfomance; results showed how a more accurate and detailed control of the porosity of the end windings can lead to sensible cooling improvements.
An alternative external cooling design consisting of a new fan and fan cover was also considered and the impact on the overall machine efficiency was numerically investigated; a 3D printed version of the proposed cooling fan was also manufactured and used for further experimental investigation.
The methodology presented in this thesis highlights the capability of CFD to model and simulate very complex geometries and fluid flows, with a high degree of detail and flexibility, allowing accurate predictions of temperature distribution within the electrical machine to be achieved
Applicazione della classificazione National Health Service Breast Screening Pathology (NHSBSP) nella comparazione cito-istologica dei tumori mammari della cagna = NHSBSP classification use in the correlation of canine mammary tumour cytology and histopathology
Canine mammary tumours (CMT) are the most common neoplasia in bitches. Fine needle aspiration cytology (FNAC) is
a fast and inexpensive technique well-tolerated by animals. Few reports have shown how difficult cytological diagnosis
of CMT is and how difficult benign or malignant tumours are to classify using FNAC. Cytological diagnosis has often
been inconclusive in veterinary pathology. In the diagnosis of human breast cancer, FNAC efficacy is beyond doubt due
to its high specificity. In this preliminary study, our aim is to evaluate the efficacy of NHSBSP classification, applied to
CMT. Secondly, we wish to test the usefulness of H&H stain in FNAC for CMT diagnosis. 75 FNAC specimens, from
41 dogs with mammary tumours were examined. 72/75 underwent the NHSBSP classification Histological examination
of the tumours was performed in each case for comparison purposes. All the CMTs fell under the five categories: C1 (3
cases), C2 (7 cases), C3 (38 cases), C4 (15 cases), C5 (9 cases). As regards H&H staining in our view it was more
efficacious than M.G.G. staining in distinguishing morphological cell details. Our results showed that the NHSBSP
classification gave a 94.4% correspondence level between cytological and histological findings
Un Caso di linfoma a grandi linfociti granulosi (LGL) in un cavallo: caratterizzazione istochimica ed immunofenotipica = Large granular lymphoma (LGL) in a horse: histochemical and immunophenotype characterization
The aim of this study is to confirm lymphoma diagnosis, characterize the neoplasia immunophenotype
and observe cell typologies by histochemical staining
Fluid flow and heat transfer analysis of TEFC machine end regions using more realistic end-winding geometry
Here, a typical small low-voltage totally enclosed fan-cooled (TEFC) motor (output power ∼10 kW) has been studied using computational fluid dynamics. The complexity of the end-winding geometries, often consisting of several insulated copper strands bound together, provides a challenge to the modelling and analysis of heat transfer and fluid flow phenomena occurring in the end region, which typically is an area of most interest for thermal management. Approximated geometries are usually employed in order to model the end windings to reduce the analysis time and cost. This paper presents a comparison of two cases, a typical simplified geometry and a more realistic geometry of end windings, and uses these cases to highlight the challenges and impact on predicted heat transfer. A comparison of the two models indicate that the different representations of end winding geometries can affect the heat dissipation rate through the outer housing by up to 45%
Osservazioni istochimiche e immunoistochimiche sull'ipofisi anteriore di un cane affetto da malattia di Cushing
Gli adenomi del lobo anteriore dell'ipofisi sono
neoplasie benigne piuttosto frequenti. Essi
mostrano aspetto circoscritto e accrescimento non
invasivo nei confronti dei tessuti circostanti. Il
tumore a cellule secernenti ACTH, che colpisce le
cellule cromofobe della pars anteriore dell'ipofisi,
è uno di questi e viene associato alla sindrome di
Cushing, causando evidente ipercortisolemia per
stimolazione della corteccia surrenale. Un cane
meticcio, femmina, di 7 anni, in terapia per
sospetta Sindrome di Cushing e pervenuto a
morte, è stato sottoposto ad accurato esame
necroscopico, durante il quale si procedeva tra
l'altro a prelevare ghiandole surrenali, polmone,
fegato, cute, muscoli e intera ghiandola pituitaria.
Su detti organi veniva eseguito l'esame
istopatologico per la ricerca delle lesioni tipiche
determinate dalla sindrome. Sulla ghiandola
pituitaria, aumentata notevolmente di volume,
venivano eseguite indagini istopatologiche
specifiche, mediante colorazione OFG, per
differenziare gli istotipi costituenti la pars
anteriore. Tale colorazione ha consentito di
riscontrare e identificare tra le cellule pituitarie gli
elementi acidofili, basofili e cromofobi; queste
ultime cellule, aumentate di numero, erano
d'aspetto omogeneo e formavano un nucleo
compatto e con scarso stroma al centro della
ghiandola. La caratterizzazione cromatica e la
differenziazione dai restanti istotipi ha reso
possibile identificare la neoplasia come adenoma
ipofisario di tipo "diffuso", caratterizzato per
l'appunto da cellule disposte a strati, con scarso
stroma e debole vascolarizzazione. Per verificare
l'ormonoattività  delle cellule neoplastiche si è
proceduto all'esame immunoistochimico per la
ricerca dell'ACTH. Il risultato di tale indagine ha
dato esito positivo, confermando l'intensa attività secernente delle cellule oggetto di studio
Un Infrequente caso di "spindle cell tumor" a localizzazione splenica primaria in un cane: rilievi citologici ed istopatologici, osservazioni istochimiche ed immunoistochimiche
Tutti i tumori fusocellulari derivano
verosimilmente da una unica cellula staminale
mesenchimale pluripotente. Macroscopicamente e
microscopicamente i tumori delle cellule
muscolari lisce e i tumori del tessuto connettivo
fibroso, si presentano morfologicamente simili.
Abbiamo ritenuto
interessante riferire su un cane meticcio, maschio,
di quattro anni sottoposto ad eutanasia dopo aver
mostrato letargia, anoressia e perdita di peso. Alla
necroscopia si osservava una voluminosa
neoformazione splenica di colore biancastro, dura
e di consistenza fibrosa. Il fegato si presentava
notevolmente aumentato di volume con numerose
neoformazioni di piccole e medie dimensioni.
Diversi campioni appartenenti agli organi
sopramenzionati, venivano sottoposti ad una
prima osservazione citologica. Parte di questi,
dopo fissazione in formalina venivano inclusi in
paraffina. Sezioni di 3-5 μ erano sottoposte a
colorazioni ordinarie e speciali (H. E., tricromica
di Mallory Azan e Van Gieson). Si eseguivano
prove immunoistochimiche utilizzando il seguente
algoritmo anticorpale: anti pan-citocheratine, anti
vimentina, anti fattore VIII, anti-αactina L, anti
desmina, anti CD 15, anti S-100.
La
neoplasia, altamente infiltrante, era costituita da
ampi fasci intrecciati di cellule allungate
fusiformi, fibroblastosimili, a moderato indice
mitotico, disposte in maniera ordinata, a spina di
pesce. Esse risultavano positive alla vimentina e
alla αactina L e negative alla desmina. Dette
caratteristiche ci consentivano di formulare
diagnosi di fibrosarcoma, neoplasia a infrequente
localizzazione splenica primaria, e di identificare
come metastasi della stessa, le neoformazioni
riscontrare a livello epatico
Histopathological, histochemical and immunoistochemical study on a rare case of granulocytic sarcoma in a dog
Granulocytic sarcoma is a malignant extramedullary solid tumor, composed of granulocytic precursor cells at various
levels of differentiation. Three differentiation levels are considered: blastic, immature, and differentiated, and cases
with unusual morphology. Nowadays the aid of more and more highly developed techniques allows to differentiate the
various histotypes.
We report a case of a 5 year-old female Schnautzer dog, died after a serious dyspnoea. During the autopsy the
veterinary found several neoplasias in the lungs. It has been found a very large white-greyish mediastinal neoplasia,
stuck at the trachea and several more in the parenchyma. Several samples were fixed in formalin, embedded in paraffin
and exposed to histochemistry staining (H.E., Giemsa), cytochemistry (Naphthol-AS-D-Chloroacetate), and
immunohistochemistry (anti-CD3, -CD79a, -CD45, -MPO, -CD45Ro, -CD34, -CD20, -CD68, -CD15, -CD30, -CD117,
-CD235a, -Factor VIII, -elastase and anti-Pan-cytocheratine).
Neoplasia, poorly circumscribed, was composed by a large number of neutrophil granulocytes with different degrees of
differentiation, including elements of myeloid lineage.
Cells were positive to MPO and focal to Naphtol-As-D-Chloroacetate and were negative to all the others antisera,
allowing us to exclude lymphomas, small cells carcinomas, and tumors of monocytic and erythroid origin. By these
characteristics we could diagnose a rare case of neutrophilic granulocytic sarcoma, of immature type progressing to
mature form
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