The soft-tissue restraints of the knee and its balancing capacity in total knee arthroplasty procedures

Total knee arthroplasty is a successful surgical treatment for patients with severe knee joint arthrosis. However, restoring soft-tissue function is a major challenge. Depending on the positioning of the prosthesis, the implantation procedure and the pathology of the patient, it is necessary to adjust the soft-tissue structures of the joint in order to restore the function of the knee. The assessment and adaptation of the soft-tissue envelope is a subjective process that is strongly dependent on the surgeon. This dissertation addresses these challenges and seeks quantitative guidelines for softtissue management based on a meta-analysis of the laxity of the natural knee joint. A further aim of the present study was to clarify in the scope of in-vitro investigations to what extent the loosening and removal of individual structures alters joint laxity and how far the joint can be balanced by targeted resection of soft-tissue structures. In addition, in-silico investigations within the scope of this thesis form the basis for a numerical tool to better understand the function of the ligaments and to better plan soft-tissue balancing preoperatively in the future. The investigations of the natural laxity of the knee jointin different flexion angles and loading directions by utilizing a meta-analysis show a strong dependency of the joint laxity on the flexion angle. Furthermore, the results show a distinct asymmetry of joint laxity when comparing translations in opposite directions within a certain degree of freedom. The data collected provide the surgeon with quantitative target parameters for natural soft-tissue balancing in knee arthroplasty procedures. The in-vitro investigations on 19 human knee specimens show that the restoration of soft-tissue function of the knee after arthroplasty cannot be achieved by kinematic alignment alone. The use of a bicruciate-retaining knee arthroplasty is the only way to keep the anterior and posterior stability of the joint in balance. To correct varus deformities, balancing of the medial collateral ligament appears to be a safe method. Correction of valgus laxity can be achieved by partially or completely resecting the lateral collateral ligament, however this increases the risk of instability in joint flexion. Within the scope of this work, subject-specific multi-body simulation models could be developed with which the laxity of the knee joint can be predicted, especially for low flexion angles. The presented procedure for the approximation of the ligament attachment sites represents a time-saving alternative to the segmentation of the attachments in MRI images.Deutsche Forschungsgemeinschaft/Sachbeihilfe/HU 873/7-1/E

Superfluid to Mott insulator transition in one, two, and three dimensions

We have created one-, two-, and three-dimensional quantum gases and study the superfluid to Mott insulator transition. Measurements of the transition using Bragg spectroscopy show that the excitation spectra of the low-dimensional superfluids differ significantly from the three-dimensional case

Maximal length of trapped one-dimensional Bose-Einstein condensates

I discuss a Bogoliubov inequality for obtaining a rigorous bound on the maximal axial extension of inhomogeneous one-dimensional Bose-Einstein condensates. An explicit upper limit for the aspect ratio of a strongly elongated, harmonically trapped Thomas-Fermi condensate is derived.Comment: 6 pages; contributed paper for Quantum Fluids and Solids, Trento 2004, to appear in JLT

Avaliação da durabilidade das propriedades mecânicas e reação ao fogo dos painéis de derivados de madeira

Mestrado de dupla diplomação com a UTFPR - Universidade Tecnológica Federal do ParanáA madeira e painéis de derivados de madeira tem sido fortemente utilizado na construção civil nos últimos anos, principalmente devido às políticas de sustentabilidade. Devido a isso, houve a necessidade de desenvolver normativas de segurança contra incêndio para produtos utilizados na construção civil fazendo com que as empresas desenvolvessem e aplicassem produtos retardantes de chamas nos seus materiais, com o intuito de diminuir a taxa de libertação de calor e o tempo de ignição da chama. Os produtos de madeira quando expostos às condições climáticas, tais como humidade, temperatura e radiação UV podem perder a sua durabilidade que acabam influenciando nas propriedades mecânicas e de reação ao fogo. Neste trabalho é apresentada uma avaliação do desempenho da durabilidade através de ciclos de envelhecimento artificial dos painéis derivados de madeira com e sem retardante de chama, com o objetivo de avaliar possíveis perdas nas propriedades mecânicas e reação ao fogo. Foram efetuados ciclos de envelhecimento artificial segundo a ETAG 028:2012, [1], com variações de humidade e temperatura durante 10 dias ininterruptos nos painéis de MDF com e sem retardante de chamas, PB com e sem retardante de chamas e OSB sem retardante de chamas. Após o envelhecimento, utilizou-se o teste de flexão em três pontos segundo a EN 310:1993, [2], com o objetivo de avaliar e comparar as propriedades mecânicas dos painéis antes e após o envelhecimento artificial, no que diz respeito à tensão máxima de flexão (MOR) e módulo de elasticidade (MOE). O estudo da reação ao fogo também foi realizado através do calorímetro de perda de massa utilizando a ISO 5660-1, [3], afim de avaliar se as propriedades de reação ao fogo foram mantidas ou alteradas após o envelhecimento dos painéis de acordo com a EN 16775:2017, [4]. Em termos de propriedades mecânicas, todos os painéis apresentaram perdas significativas nos valores de MOR e MOE com exceção do OSB que possuí uma resina de pMDI resistente à humidade. As reduções nas propriedades mecânicas foram menores para os painéis de MDF com retardante de chamas quando comparado ao MDF sem retardante de chama enquanto que o PB sem retardante de chama apresentou perdas menores do que em relação ao PB com retardante de chamas. Os painéis de MDF sem retardante de chama apresentaram perdas nas propriedades de reação ao fogo, libertando mais calor nas amostras após o envelhecimento, enquanto que no PB e OSB sem retardante de chama, as propriedades foram mantidas. Os painéis ignífugos de MDF e PB não perderam a durabilidade e continuaram na classe B de reação ao fogo.The use of wood and wood panels has been heavily used in civil construction in recent years, mainly due to sustainability policies. Due to this, there was a need to develop fire safety regulations for products used in construction, causing companies to develop and apply flame retardant products in their materials in order to reduce the heat release rate, the ignition time and avoiding the flame propagation. Wood products when exposed to weathering conditions, such as humidity, temperature and UV radiation, can lose their durability, influencing the mechanical properties and fire reaction. In this work, a durability evaluation performance through the artificial aging cycles of the wood panels with and without flame retardant is presented, in order to evaluate if there were losses in the mechanical properties and fire reaction. Artificial aging cycles according to ETAG 028: 2012 were performed with humidity and temperature variations for 10 days without interruption in MDF panels with and without flame retardant, PB with and without flame retardant and OSB without flame retardant. After aging, the three-point bending test according to EN 310: 1993 was used to evaluate and compare the mechanical properties of the panels before and after the climatic aging with respect to bending resistance (MOR) and modulus of elasticity (MOE). The study of fire reaction was also carried out through the mass loss calorimeter, in accordance with ISO 5660-1, to evaluate if the fire reaction properties were maintained or altered after exposure of the panels to environmental conditions according to EN 16775: 2017. In terms of mechanical properties, all panels had significant losses in MOR and MOE values except for OSB which had a moisture resistant pMDI resin. Reductions in mechanical properties were lower for MDF panels with flame retardant when compared to MDF without flame retardant whereas PB without flame retardant showed less losses than with PB with flame retardant. The MDF panels without flame retardant presented losses in the fire reaction properties, releasing more heat in the samples after aging, whereas in the PB and OSB without flame retardant properties were maintained. The MDF and PB fire retardant panels did not lose their durability and continued in the fire reaction class B

Impactos causados no controle externo pela alteração da Lei de Introdução às Normas de Direito Brasileiro, sob a perspectiva do artigo 20 caput, §1º e artigo 22 caput, §1º da Lei 13.655/2018 - LINDB

Essa monografia, tem como tema os impactos causados no Controle Externo em razão da alteração da Lei de Introdução às Normas de Direito Brasileiro, sob a ótica do artigo 20 caput, §1º e 22 caput, §1º da Lei 13.655/2018. O estudo tem por escopo compreender quais disfuncionalidades do Direito Administrativo Sancionador, conduziram à edição da Nova LINDB. As justificativas de embasamento desse novo diploma legal, a recepção e percepção inicial pelos agentes públicos e examinar como os profissionais do ramo jurídico e os executores das leis têm se adaptado às novas demandas normativas estabelecidas pela LINDB. A relevância do trabalho se assenta na modificação irremediável dos parâmetros de controle para regularidade ou validade de ato administrativo, para a correta aplicação desses dispositivos é necessário compreender as alterações com maior densidade, por essa razão fazemos o corte metodológico sob a perspectiva dos 20 caput, §1º e 22 caput, §1º. Para esse propósito, utiliza-se o método dedutivo tendo realizado pesquisa na doutrina, legislação administrativa, jurisprudência e linhas de pesquisas relacionadas ao tema. Ao final, o estudo apresenta ponderações com o objetivo de aprimorar a compreensão dos novos aspectos decorrentes da LINDB, suas implicações jurídicas, administrativas e práticasThis monograph has as its theme the impacts caused in the External Control due to the amendment of the Law of Introduction to the Standards of Brazilian Law, from the perspective of article 20 caput, §1 and 22 caput, §1 of Law 13.655/2018. The scope of the study is to understand which dysfunctions of the Administrative Law Sanctioning led to the edition of Nova LINDB. The justifications for the basis of this new legal diploma, the reception and initial perception by public agents and examine how legal professionals and law enforcers have adapted to the new normative demands established by LINDB. The relevance of the work is based on the irremediable modification of the control parameters for regularity or validity of administrative act, for the correct application of these devices it is necessary to understand the changes with greater density, for this reason we make the methodological cut from the perspective of 20 caput, §1 and 22 caput, §1. For this purpose, the deductive method is used, having conducted research on doctrine, administrative legislation, jurisprudence and lines of research related to the subject. At the end, the study presents weightings with the objective of improving the understanding of the new aspects arising from LINDB, its legal, administrative and practical implication

Portal corporativo Sicredi e estratégias de gestão de pessoas

O objetivo principal deste estudo foi avaliar como o Portal Corporativo SICREDI pode apoiar / sustentar as estratégias de gestão de pessoas do SICREDI. Considerando aspectos apontados por alguns dos principais autores na área de gestão estratégica de pessoas, mudança organizacional e cultura corporativa, bem como tecnologia da informação em recursos humanos, avaliou-se a percepção de gestores de área e colaboradores da área de gestão de pessoas quanto à sustentação das estratégias de gestão de pessoas pelo Portal Corporativo SICREDI. Assim, com a análise qualitativa dos dados obtidos com os entrevistados, verificou- se, entre outras necessidades, que é preciso trabalhar a cultura corporativa, a fim de que os colaboradores do Sistema percebam a relevância do Portal na comunicação organizacional, utilizando-o adequadamente , de modo a trazer ganhos para a organização, já que ao conhecer o seu papel no Sistema, o colaborador tende a melhorar seu desempenho e, conseqüentemente, os resultados da organização

Χαρτογράφηση της ενεργοποίησης της μικρογλοίας στις περιοχές του προμετωπιαίου φλοιού, του ιπποκάμπου και της αμυγδαλής μετά από πρόκληση χρόνιου στρες κοινωνικής ήττας

ΕΙΣΑΓΩΓΗ: Η έκθεση σε πρώιμες στρεσογόνες εμπειρίες επηρεάζει καθοριστικά την ανάπτυξη και τη λειτουργία του κεντρικού νευρικού συστήματος. Όταν αυτή δε ακολουθείται από έκθεση σε χρόνιους στρεσογόνους παράγοντες κατά την ενήλικο ζωή, οι αρνητικές επιπτώσεις τους στρες ενισχύονται. Η μικρογλοία είναι μία κατηγορία κυττάρων του ανοσοποιητικού αλλά και του νευρικού συστήματος που μελετώνται ως πιθανοί διαμεσολαβητές αυτού του φαινομένου ενίσχυσης. ΣΚΟΠΟΣ: Στην παρούσα μελέτη διερευνήσαμε το πρότυπο ενεργοποίησης της μικρογλοίας μετά την έκθεση σε ψυχοκοινωνικό στρες μόνο κατά την νεογνική περίοδο, μόνο κατά την ενήλικο ζωή και κατά τη διαδοχική τους συνύπαρξη. ΥΛΙΚΑ & ΜΕΘΟΔΟI: Για το σκοπό αυτό αξιοποιήθηκαν δύο ζωικά πειραματικά μοντέλα στον επίμυ. Η νεογνική εκπαίδευση σε λαβύρινθο σχήματος Τ υπό συνθήκες άρνησης ή λήψης της ανταμοιβής −νεογνικό μοντέλο ήπιας αντιξοότητας− και το χρόνιο στρες κοινωνικής ήττας στους ενήλικες. Για τον χαρακτηρισμό του προτύπου ενεργοποίησης της μικρογλοίας στον εγκέφαλο, και συγκεκριμένα στις περιοχές του ιπποκάμπου, του προμετωπιαίου φλοιού και της αμυγδαλής, διενεργήθηκε: α) ανοσοϊστοχημικός εντοπισμός της πρωτεΐνης Iba-1 –γενικός κυτταρικός δείκτης της μικρογλοίας– ώστε να αποτιμηθεί αριθμητικά ο πληθυσμός της μικρογλοίας, και β) ποσοτική αλυσιδωτή αντίδραση πολυμεράσης αντίστροφης μεταγραφής των γονιδίων PPARγ, IL-1β και TNFa ώστε να προσδιοριστεί το ανοσολογικό προφίλ της μικρογλοίας. ΑΠΟΤΕΛΕΣΜΑΤΑ: Η έρευνά μας έδειξε ότι η διαδοχή στρεσογόνων γεγονότων στην πρώιμη νεογνική περίοδο και μετέπειτα κατά την ενήλικο ζωή οδηγεί σε αριθμητική αύξηση του πληθυσμού της μικρογλοίας στον ιππόκαμπο και στον προμετωπιαίο φλοιό και σε αύξηση της σχετικής έκφρασης του αντιφλεγμονώδους παράγοντα PPARγ στον ιππόκαμπο. ΣΥΜΠΕΡΑΣΜΑΤΑ: Μια ήπια πρώιμη στρεσογόνος εμπειρία, ενώ από μόνη της δεν επηρεάζει τη μικρογλοία, όταν συνοδεύεται από στρες κατά την ενήλικο ζωή εμφανίζει να έχει σημαντική επίπτωση σε κυτταρικό και μοριακό επίπεδο. Το φαινόμενο αυτό έρχεται σε συμφωνία με την "Υπόθεση των δύο χτυπημάτων", όπου η ευαλωτότητα στο στρες κατά την ενήλικο ζωή καθορίζεται σε μεγάλο βαθμό από την ποιότητα των πρώιμων εμπειριών. Ένα φαινόμενο ιδιαίτερης κοινωνικής αξίας, καθώς επισημαίνει την κρισιμότητα των παιδικών χρόνων στον μακροπρόθεσμο καθορισμό της υγείας και της ποιότητας ζωής.INTRODUCTION: Early life stressful experiences strongly affect both developmental and functional processes of the central nervous system. When followed by chronic stressors in adulthood, the negative effects of stress are enhanced. Microglia is a class of cells belonging both to the immune and the nervous system and is thought to be a potential mediator of this enhancement phenomenon. AIM: In the present study we investigated the pattern of microglial activation as an effect of psychosocial stress during childhood alone, during adulthood alone and at their succession. MATERIALS & METHODS: For this purpose, we used two experimental animal models in the rat. The neonatal training in the T-maze under denial or receipt of reward –a neonatal model of stress of mild adversity– and the model of chronic social defeat at the adults. In order to characterize the microglial activation pattern in the brain, namely in the hippocampus, prefrontal cortex and amygdala, we used: a) immunohistochemistry detection of Iba-1 –a generic cell marker of microglia for all its phenotypes– to estimate the size of microglial population and b) quantitative reverse transcriptase polymerase chain reaction for PPARγ, IL-1β and TNFα genes to determine the immunological profile of microglia. RESULTS: Our results suggest that the succession of stressful events in the early neonatal years and later in adulthood lead to a numerical increase of the microglial population in the hippocampus and the prefrontal cortex and to an increase in the relative expression of the anti-inflammatory marker PPARγ in the hippocampus. CONCLUSIONS: A mild early life stressful experience, while it does not affect microglia per se, when followed by stress during adulthood it appears to have a significant effect on a cellular and molecular level. This phenomenon is in line with the "Two-hit hypothesis", where the vulnerability to stress of an adult is largely determined by the quality of early life experiences. A phenomenon of great value for the society, since it highlights the significance of childhood in the long-term determination of health and wellbeing

Cyber peers’ influence for adolescent consumer in decision-making styles and online purchasing behavior

[[abstract]]Nowadays, there is a boom in online purchasing, especially by adolescents. In fact, scholars and marketers alike have long noticed the emergence of adolescent consumers and their consumption behaviors. This research aims at exploring the effect of adolescent decision-making styles on online purchasing behavior, with peer influence as a moderating variable. An online questionnaire survey was conducted on 2,419 adolescents and further verified by regression analysis and analysis of covariance. Adolescents with planned purchase behaviors can be considered as rational consumers, in that they do not care about fashion, or recreational, hedonistic shopping consciousness, but rather focus on brand, price value, and high quality. Indeed, adolescent purchase decision making can be strengthened by peer influence.[[journaltype]]國外[[incitationindex]]SSCI[[ispeerreviewed]]Y[[booktype]]電子版[[booktype]]紙本[[countrycodes]]US