4 research outputs found
Resisting The Iron Law of Oligarchy: case of community energy system
No full textThe iron law of oligarchy claims that the complex organisation will always end up in an oligarchy, no matter it was constituted originally. In that sense, the oligarchy should also happen in the Community Energy System (CES) as a complex self-govern common-pool resource system. The oligarchy situation raises the issue of the fairness and the health in the community since that subgroup of the member may steer the future decisions to be more favourable on one side than the others or may drive the rules to limit the active participation of others, or decrease the community cohesion. This paper specially concerned with the emergence of oligarchy in the CES and the effect of the iron law of oligarchy on the health and the fairness in the CES. The result shows that the iron law of oligarchy occurs in CES, but it is needed to make CES has the level of fairness and health required to support its continuit
Analysis of Satisfaction Level of BPJS Card Users With the Services Provided at Tarutung General Hospital Using Importance Performance Analysis Method (IPA)
No full textIn improving the quality of service to provide satisfaction to patients, hospital staffneed to make efforts to meet the expectations of patients so that patients the hospital. Sothat quadrant I, Quadrant II, Quadrant III, and Quadrant IV are the results from the Cartesiandiagram based on the level of interest and performance that has been set. So to find out howthe level of patient satisfaction using the Social Security User Agency (BPJS) card with theservices provided by Tarutung General Hospital is measured, patient satisfaction is measuredusing the Importance Performance Analysis (IPA) method. From the results of 20 statementsgiven to 70 respondents using BPJS cards, there were 2 attributes whose performance waslow so the hospital had to make them a priority for improvement. The first attribute that is apriority for improvement is in quadrant (I) namely the availability of a comfortable and adequate waiting room and seat with a satisfaction level (72.83%) and the second improvementis in quadrant (III) namely cleanliness and comfort in the hospital. with a level of satisfaction(79.87%). With the Wilcoxon signed rank test method, which aims to determine the difference between the quality of service expected by patients using BPJS cards and the quality ofservice received by patients, there is a big difference, namely in the availability of waitingrooms and seats. comfortable and adequate with a value of 6,367
Carlos Ribeiro (1813-1882) and the dolmens of Belas: a contribution for the History of Science in Portugal during the nineteenth century
No full textAn evaluation of Carlos Ribeiro’s (1813-1882) work regarding the excavation of four dolmens in the outskirts of Belas (Sintra, Portugal) is presented here. These excavations were initiated in 1875 and extended intermittently until 1878. The results were exemplarily published in a monograph in 1880 containing rigorous descriptions of the monuments and its respective findings (portrayed by beautiful charcoal drawings of the tombs and its findings). The quality of graphic recording is accompanied by a discussion regarding the importance of observing: the construction techniques adopted; how the terrain and geologic background conditioned its construction; as well as the type of raw materials used in the making of artifacts and its meaning.
Thanks to Carlos Ribeiro’s own manuscript notes it was possible to complement his published work. These notes are comprised of preliminary parts of the published work together with field observations conducted during the excavations. Also, they were intersected with notations from other publications compiled by Carlos Ribeiro which he used in the discussion of his own results. These documents illustrate how based on a scientific method the author built his archaeological discourse, emerging as one of the pinnacles in his field of knowledge in Portugal, together with his colleagues of the Geological Commission, Francisco Pereira da Costa and Joaquim Filipe Nery Delgado.
Besides illustrating the production of scientific discourse, based on data collected in the field, and then in the lab until its final result, this paper also provides information regarding the number of field work days and respective participants in the last phase of excavations conducted during most of the Summer of 1878 at the monuments of Monte Abraão, Estria and Carrascal/Agualva
Microvascularização arterial da cóclea
No full textRESUMO: Na descrição deste estudo foi utilizada a terminologia anatómica da Sociedade
Brasileira de Anatomia adaptada ao português por J. A. Esperança-Pina de acordo
com o tratado Anatomia Humana da Relação.
Os actuais estudos sobre hipoacusia sensorioneural implicam um grupo crescente
de situações, em que a lesão se situa ao nível da microvascularização coclear,
daí que o conhecimento exacto da angiomorfologia normal se torne essencial na
fase actual do conhecimento.
A autora tem vindo a estudar, desde 1986, a angiomorfologia do ouvido Interno
no modelo experimental, o Cobaio, utilizando várias técnicas microvasculares.
sendo dado enfâse particular neste estudo à técnica de microscopia electrónica de
varrimento em moldes vasculares.
Os animais usados no presente estudo pertencem à espécie cavia porcellus, cobaio,
por serem considerados na comunidade cientifica internacional como o melhor
modelo experimental para estudo do ouvido interno, pelo facto de a morfologia coclear
ser muito semelhante à do Homem e por isso ser um modelo fiável para cirurgia experimental
e microdissecção. Este estudo foi realizado em 100 cobaios, cavia porcellus,
de ambos os sexos com peso médio de 450g.
A vascularização do ouvido interno, no cobaio como no homem, faz-se através
dos ramos de divisão da artéria auditiva interna ou labiríntica. A artéria labiríntica
origina-se como ramo colateral da artéria cerebelosa ântero-inferior a qual tem origem
na artéria basilar ou na artéria vertebral.
Embora no homem a artéria auditiva interna possa também destacar-se da artéria
basilar e até da artéria vertebral, no cobaio em todos os casos estudados a sua
origem verificou-se sempre na artéria cerebelosa ântero-inferior.
A artéria labiríntica, ao passar abaixo do meato auditivo interno, divide-se na
artéria vestibular anterior e na artéria coclear comum.A artéria vestibular anterior dirige-se para o nervo vestibular, emite vasa nervorum
para este nervo e vasculariza o utrículo e os canais semicirculares.
A artéria coclear comum origina dois ramos principais, a artéria vestíbulo‑coclear
ou vestibular posterior no cobaio, a qual se destaca junto à espira basal da cóclea e a
artéria coclear, como ramo terminal, que passa a denominar-se de artéria modiolar
ou espiralada, após entrar no modíolo.
A artéria modiolar ascende no modíolo promovendo através dos seus ramos
colaterais e dos seus ramos terminais a microvascularização coclear, numa vascularização
de órgão de tipo terminal. Ao longo do seu trajecto verificou‑se de modo
constante uma redução gradual de calibre em cada uma das espiras, por emissão de
ramos colaterais, sendo que o calibre da artéria na base da cóclea apresenta um valor
que diminui gradualmente até ao ápice.
A artéria modiolar origina em todo o seu trajecto ramos colaterais, cujo número
diminui em valor absoluto da base para o ápice:
Arteríolas radiárias internas, arteríolas de trajecto flexuoso que caminham junto
às estruturas sensorioneurais da parede interna da cóclea, junto ao lábio timpânico
da lâmina espiral óssea e na parede do próprio modíolo, que se relacionam intimamente
com este. As arteríolas radiárias internas originam‑se no flanco da artéria
modiolar espiralada. Contam‑se dez a doze em cada espira, extraordinariamente
flexuosas desde a sua origem. As arteríolas radiárias internas originam como ramos
colaterais, vários grupos de arteríolas de menor calibre, que vascularizam distintas
regiões da parede interna da cóclea, as arteríolas do gânglio espiral, a rede espiral
interna, as arteríolas de origem dos glomérulos de Schwalbe e a arteríola da
lâmina basilar. As arteríolas radiárias externas importantes ramos colaterais da artéria
modiolar espiralada promovem a vascularização de importantes estruturas da
parede externa. Ao atingir o limite externo do ligamento espiral, as arteríolas radiárias
externas dividem‑se em vários ramos arteriolares de menor calibre, ao longo
da convexidade do limite externo do ligamento espiral, originando a rede capilar
pós-estriada que ocupa a porção lateral do ligamento espiral e a rede capilar ad‑
-estriada, na sua porção mais medial em íntima relação com a estria vascular.
A espira basal da cóclea apresenta grande riqueza de vascularização, com
características particulares apenas a esta espira, a qual é metabolicamente a mais
exigente.
A arteríola da janela da cóclea aborda a janela da cóclea pela sua convexidade e
divide-se numa rica rede vascular da qual emergem arteríolas pré-capilares que se ramificam em capilares, os quais se dirigem em profundidade penetrando a rampa
timpânica da cóclea ao nível da espira basal.
Importou neste estudo verificar quais as semelhanças em termos de calibre de
estruturas análogas, na parede interna e na parede externa da cóclea, com particular
incidência na rede capilar.
Do estudo estatístico realizado com testes paramétricos de Tamahane e não paramétricos de Mann-Whitney, verifica-se que comparando todas as estruturas consideradas estas têm calibres diferentes, com excepção dos capilares da estria vascular e do ligamento espiral, pertencentes à parede externa da cóclea que têm calibres iguais aos capilares da rede espiral interna e aos capilares da parede interna da cóclea, dependentes das arteríolas da rede espiral interna.
As redes capilares dependentes das arteríolas radiárias internas que vascularizam as estruturas sensorioneurais junto á parede interna do modiolo são em tudo
semelhantes em termos de calibre às redes capilares da parede externa da cóclea,
incluindo os capilares da estria vascular.
Esta particularidade traduz num órgão com vascularização de tipo terminal,um mecanismo de controlo do fluxo sanguíneo coclear tão importante na parede interna como na parede externa da cóclea. ------------ ABSTRACT:Current studies on sensorineural hearing loss, imply a growing group of situations
in which the lesion is located at the level of the cochlear microvasculature,
hence the exact knowledge of normal angiomorfology becomes essential in current
state of knowledge.
The author has been studying since 1986, the angiomorfology of inner on the
experimental model, the guinea pig, using various microvascular techniques being
given particular emphasis in this study to the results of the technique of scanning
electron microscopy on corrosion casts.
The animals used in this study belong to the species cavia porcellus, guinea pig,
to be considered in the international scientific community as the best experimental
model for the study of the inner ear, the cochlear morphology is very similar to
human and therefore a reliable model for experimental surgery and microdissection.
This study was performed in 100 guinea pigs of both sexes with average weight
of 450g.
There shall be a brief description of embryology, anatomy and cochlear physiology
in the light of developmental biology, regarding also the spatial location of
the cochlea and the determinism of morphogenetic fields in their development and
function.
The cochlear transduction mechanism converts the sound wave in stimuli sound
and so afferent auditory nerve fibres and deafness are closely related to the cochlear
microvasculature. Cochlear ischemia is accompanied by immediate hearing loss.
The different type of cochlear injury that leads to sensorineural deafness is well
studied in presbycusis where an objective link with the audiometric pattern as been
established.
The sensory type of deafness, is closely related to the degeneracy of the organ
of Corti and damage to the outer hair cells at the basal turn of the cochlea. Keeping in mind cochlear tonotopy with location of high frequency sounds at
the level of the base of the cochlea, it explains the audiometric pattern with loss in
high frequencies.
The neural type of deafness, is characterized by neuronal loss with loss of
descendant important neuronal afferents, with audiometric translation on a gradually
curve with important loss of auditory discrimination.
The metabolic type of deafness results in atrophy of the vascular stria, with consequent
change in the potential of the endolymph by decreasing the vascular stria
cells and changes in K + recycling mechanism. There is also a change in the morphology
of the spiral ligament and the audiometric patern as a flattened curve with
loss at all frequencies.
Bearing in mind cochlear tonotopy and being characterized all types of sensorineural
deafness, we may inquire to what extent the cochlear microvasculature, considering
not only the cochlea as a whole but different regions of the inner wall and
the outer wall of the cochlea, contributes to deafness.
We analysed the entire cochlear morphology on scanning electron microscopy
with particular emphasis on bone and membranous cochlea. The inner wall of the
cochlea and intramodiolar structures such as the spiral ganglion, the morphology of
its cell bodies and their axons are analyzed.
The morphology of Corti’s organ is described in detail, with description and
large detail of the inner and outer hair cells.
Is then presented the study of the microvasculature itself.
The spiral modiolar artery is observed with the diaphanization technique and
the technique of scanning electron microscopy on corrosion vascular casts.
After emergence of collateral branches of the greatest importance, the radiating
internal and external arterioles, the modiolar artery gives rise to its terminal
branches, the arterioles of the cochear apex.
Arterial vasa vasorum and vasa nervorum are displayed with a great detail,
which was not yet described in such detail in previous microvascular studies.
The arterial radiating arterioles originate in the flank of the spiral modiolar
artery in number of ten to twelve in each loop, and they vascularize through their
branches the inner wall cochlear sensorineural structures located in the modiolus as
the spiral ganglion and structures near the organ of Corti.
Their caliber is above 20 μm on the basal turn and in the second loop it decreases
to values between 12 and 20 μm, decreasing progressively to the apex of the cochlea.They arise near the modiolus or on their way in the spiral lamina forming vascular
loops, and divide without presenting vascular constrictions in their divisions, originating
new vascular loops of lower caliber.
Internal ratiating arterioles originate as collateral branches several groups of
smaller caliber arterioles, which vascularize distinct regions of the inner wall of the
cochlea namely, the arterioles of the spiral ganglion, the internal spiral network,
the arterioles of origin of the glomeruli of Schwalbe and the arterioles of the basilar
membrane.
The glomeruli of Schwalbe play an important functional role as relay-stations, in
hemodynamic terms, to control the cochlear microvasculature.
External radiating arterioles have their origin in the spiral modiolar artery, they
are directed towards the outer wall of the cochlea and run through the roof of the
scala vestibuli.
Above the insertion of Reissner’s membrane on the external wall the external
radiating arterioles originate the spiral ligament arterioles, which vascularize the
spiral ligament, they divide into several arteriolar branches of smaller caliber, along
the convexity of the outer edge of the spiral ligament. The connective tissue of the
spiral ligament forms a mesh with supporting function of the highly specialized epithelium,
where pericytes were identifiable.
Next to its base there is the microvascular network of stria vascularis. The adstriated
vascular network which is divided into a capillary network, the capillary
network of stria vascularis.
The stria vascularis, the only vascularized epithelium of the human body, plays
an important role, forming an haemato-labyrintine barrier to assure labyrinthine
endocochlear potential and transport of ions, essential for the mechanism of transduction
of external hair cells.
The cochlear basal turn has a special feature on its external wall, the region of the
windows, the round windows giving access to scala tympani and the oval window
thatleads into scala vestibuli, and so it is metabolic demanding.
For their role in cochlear tonotopy the sensorineural structures and those of the
external wall of the cochlea, are particularly vulnerable to hypoxia.
Although the complementarity of all the techniques was important for three-
-dimensional reconstruction of the microvasculature of the cochlea, the scanning electron
microscopy technique, especially when we used the system Semafore was fundamental
to perform precise morphometric mesures regarding all vascular structures.Regarding the capillaries of the inner and outer wall of the cochlea networks this
technique allowed their characterization in morphometric terms.
To conclude the capillaries of the inner wall and of the external wall of the
cochlea have similar size.
So although located at different cochlear regions, with a different functional role,
in cochlear physiology these networks consist of capillaries of similar caliber.
It seems to translate a cochlear blood flow control mechanism that is so important
in the inner wall as in and the external wall of the cochlea to provide for in inner
ear homeosthasia
