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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Community Pharmacists’ Perceptions of Neonatal Abstinence Syndrome and Opioid-Based Medication-Assisted Treatment in Northeast Tennessee

Sevak, Rajkumar J., Click, Ivy, Basden, Jeri Ann, Hagemeier, Nicholas E. 18 October 2015 (has links)
Abstract available through Pharmacotherapy.
262

Introduction to the Opioid Epidemic: The Economic Burden on the Healthcare System and Impact on Quality of Life

Hagemeier, Nicholas E. 11 May 2018 (has links)
Opioid analgesics are commonly used to treat acute and chronic pain; in 2016 alone, more than 60 million patients had at least 1 prescription for opioid analgesics filled or refilled. Despite the ubiquitous use of these agents, the effectiveness of long-term use of opioids for chronic noncancer pain management is questionable, yet links among long-term use, addiction, and overdose deaths are well established. Because of overprescribing and misuse, an opioid epidemic has developed in the United States. The health and economic burdens of opioid abuse on individuals, their families, and society are substantial. Part 1 of this supplement will provide a background on the burden of pain and the impact of opioid abuse on individuals, their families, and society; the attempts to remedy this burden through prescription opioid use; and the eventual downward spiral into the current opioid epidemic, including an overview of opioid analgesics and opioid use disorder and the rise in opioid-related deaths
263

Perspectives of Sierra Leoneans Healthcare Workers' Mental Health During the Ebola Outbreak

Taylor, Guy O 01 January 2019 (has links)
The mental health of healthcare workers during the Ebola outbreak in West Africa was a serious concern for healthcare professionals and the mental health field. One area in West Africa where healthcare workers played a significant role during the Ebola outbreak of 2014 and 2015 was Sierra Leone. This qualitative research study was designed to explore the perceptions of Sierra Leoneans healthcare workers' mental health, how they coped, and treatment they received while providing care for Ebola virus patients. This study, with a phenomenological research approach, used purposeful sampling to recruit 10 healthcare workers to participate in semi structured, open-ended interviews. The stress theory model and a hermeneutic phenomenology conceptual framework were used as a lens of analysis to understand the views of healthcare workers who worked directly with Ebola virus patients in Freetown, Sierra Leone. The results of the analysis of the collected data produced 9 major themes. The major themes suggest that healthcare workers experienced mental health symptoms such as depression and anxiety, personal thoughts and feelings such as insomnia, and suicidal ideation. Strategies for coping included using the Bible; and the detrimental impact included facing discrimination after the Ebola outbreak. Most of the healthcare workers blame the government for not providing adequate coping resources, which led to the personal consequence of hopelessness. This study may benefit mental health professionals working in an epidemic. Additionally, this study may contribute to social change by providing a deeper understanding of the mental health system and healthcare workers in Freetown, Sierra Leone.
264

Invisible demons : epidemic disease and the Plains Cree : 1670-1880

Brain, Rebecca Lee Barbara 03 December 2007
It is evident from the past forty years of research, debate and literature that the New World was far more populated in 1492 than was previously thought. However, despite the expanding field of study most works omit the effects that epidemics had on the tribes of the Great Plains, particularly those located in present-day Canada, and the works that have been published deal mainly with demographics and fail to delve into how disease affected intertribal relations. As well, almost all studies of disease and the Great Plains tribes end by 1850 or start in 1880. Therefore, the decades from 1860 through to the 1870s are largely ignored and become even more of a mystery when considering the fact that the eventual subjugation of the Plains Natives soon came when the Numbered Treaties commenced in 1871.<p>The omission of research on epidemics from 1860 to 1880 has left historians to concentrate on other reasons for the collapse of the Plains lifestyle, primarily the disappearance of the buffalo, which was crucial to Native existence in the parkland/grassland regions. Although this was obviously a very important factor in weakening warrior societies on the Plains, it was by no means the sole factor. In fact, the smallpox epidemic of 1870-71 and its after effects played an important role in debilitating Native nations, especially great tribes like the Plains Cree in present-day Saskatchewan. Food supplies could not be maintained and starvation became prevalent throughout the Great Plains in the winter of 1870-71. Malnutrition certainly would also have led to further secondary complications such as fertility problems and pulmonary illnesses, such as pneumonia, which would have contributed to the impact of the epidemic through a continued loss of population and disruption of intertribal functioning. Through analysis of the consequences of this epidemic on the Plains Cree it becomes increasingly apparent that disease played a much greater role in leading Natives towards treaty negotiations and settlement than has been formerly thought. This is not to say that epidemics in themselves were the main reason for the collapse of the Plains Cree culture, but rather they deserve to be included along with the traditional causes such as the disappearance of the buffalo.
265

Robustness against large-scale failures in communications networks

Segovia Silvero, Juan 15 December 2011 (has links)
This thesis studies robustness against large-scale failures in communications networks. If failures are isolated, they usually go unnoticed by users thanks to recovery mechanisms. However, such mechanisms are not effective against large-scale multiple failures. Large-scale failures may cause huge economic loss. A key requirement towards devising mechanisms to lessen their impact is the ability to evaluate network robustness. This thesis focuses on multilayer networks featuring separated control and data planes. The majority of the existing measures of robustness are unable to capture the true service degradation in such a setting, because they rely on purely topological features. One of the major contributions of this thesis is a new measure of functional robustness. The failure dynamics is modeled from the perspective of epidemic spreading, for which a new epidemic model is proposed. Another contribution is a taxonomy of multiple, large-scale failures, adapted to the needs and usage of the field of networking. / Esta tesis estudia la robustez contra fallos de gran escala en redes de comunicaciones. Si los fallos son aislados, usualmente pasan inadvertidos para los usuarios gracias al uso de mecanismos de recuperación. Sin embargo, tales mecanismos no son efectivos contra fallos múltiples de gran escala. Los fallos de gran escala pueden causar grandes pérdidas económicas. Un requisito clave a la hora de diseñar mecanismos efectivos para reducir los efectos negativos es la habilidad de evaluar la robustez de la red. Esta tesis se centra en redes multinivel que poseen planos de control y de datos separados. La mayoría de las medidas de robustez existentes no capturan correctamente la verdadera degradación de los servicios en tales escenarios porque basan la evaluación en propiedades puramente topológicas. Una de las contribuciones de esta tesis es una nueva métrica de robustez funcional. La dinámica de los fallos se modela desde la perspectiva de la propagación de epidemias, para lo cual un nuevo modelo epidémico es propuesto. Otra contribución es una taxonomía de los fallos múltiples de gran escala, adaptado a las necesidades y uso del campo de las redes de comunicaciones.
266

Invisible demons : epidemic disease and the Plains Cree : 1670-1880

Brain, Rebecca Lee Barbara 03 December 2007 (has links)
It is evident from the past forty years of research, debate and literature that the New World was far more populated in 1492 than was previously thought. However, despite the expanding field of study most works omit the effects that epidemics had on the tribes of the Great Plains, particularly those located in present-day Canada, and the works that have been published deal mainly with demographics and fail to delve into how disease affected intertribal relations. As well, almost all studies of disease and the Great Plains tribes end by 1850 or start in 1880. Therefore, the decades from 1860 through to the 1870s are largely ignored and become even more of a mystery when considering the fact that the eventual subjugation of the Plains Natives soon came when the Numbered Treaties commenced in 1871.<p>The omission of research on epidemics from 1860 to 1880 has left historians to concentrate on other reasons for the collapse of the Plains lifestyle, primarily the disappearance of the buffalo, which was crucial to Native existence in the parkland/grassland regions. Although this was obviously a very important factor in weakening warrior societies on the Plains, it was by no means the sole factor. In fact, the smallpox epidemic of 1870-71 and its after effects played an important role in debilitating Native nations, especially great tribes like the Plains Cree in present-day Saskatchewan. Food supplies could not be maintained and starvation became prevalent throughout the Great Plains in the winter of 1870-71. Malnutrition certainly would also have led to further secondary complications such as fertility problems and pulmonary illnesses, such as pneumonia, which would have contributed to the impact of the epidemic through a continued loss of population and disruption of intertribal functioning. Through analysis of the consequences of this epidemic on the Plains Cree it becomes increasingly apparent that disease played a much greater role in leading Natives towards treaty negotiations and settlement than has been formerly thought. This is not to say that epidemics in themselves were the main reason for the collapse of the Plains Cree culture, but rather they deserve to be included along with the traditional causes such as the disappearance of the buffalo.
267

Mobile Ad Hoc Molecular Nanonetworks

Guney, Aydin 01 June 2010 (has links) (PDF)
Recent developments in nanotechnology have enabled the fabrication of nanomachines with very limited sensing, computation, communication, and action capabilities. The network of communicating nanomachines is envisaged as nanonetworks that are designed to accomplish complex tasks such as drug delivery and health monitoring. For the realization of future nanonetworks, it is essential to develop novel and efficient communication and networking paradigms. In this thesis, the first step towards designing a mobile ad hoc molecular nanonetwork (MAMNET) with electrochemical communication is taken. MAMNET consists of mobile nanomachines and infostations that share nanoscale information using electrochemical communication whenever they have a physical contact with each other. In MAMNET, the intermittent connectivity introduced by the mobility of nanomachines and infostations is a critical issue to be addressed. In this thesis, an analytical framework that incorporates the effect of mobility into the performance of electrochemical communication among nanomachines is presented. Using the analytical model, numerical analysis for the performance evaluation of MAMNET is obtained. Results reveal that MAMNET achieves adequately high throughput performance to enable frontier nanonetwork applications with sufficiently low communication delay.
268

Μελέτη εξάπλωσης ιών σε δίκτυα

Ράπτη, Αγγελική 16 April 2015 (has links)
Η έννοια των δικτύων εμφανίζεται πολύ συχνά με διάφορες μορφές. Δίκτυο μπορούμε να θεωρήσουμε ένα σύνολο υπολογιστών που συνδέονται μεταξύ τους υπακούοντας σε κάποιο πρωτόκολλο επικοινωνίας αλλά και μια ομάδα ανθρώ- πων που συνδέονται μέσω κάποιας κοινωνικής σχέσης, ενός εργασιακού χώρου αλλά και ως χρήστες ενός forum ή μίας πλατφόρμας κοινωνικής δικτύωσης. Σε οποιαδήποτε περίπτωση, ένα δίκτυο μπορεί να αναπαρασταθεί με τη μορφή ενός γράφηματος, όπου οι κόμβοι αναπαριστούν τα άτομα/υπολογιστές και οι ακμές τη μεταξύ τους σχέση ανάλογα με το πρόβλημα. Στα πλαίσια ενός τέτοιου δικτύου μας ενδιαφέρει η συμπεριφορά των κόμβων στην περίπτωση που συμβεί ένα γεγονός που αλλάζει την κατάστασή τους. Στην περίπτωση που αναφερόμαστε σε μία κοινωνική ομάδα ή μία πόλη, αυτό το φαι- νόμενο μπορεί να είναι το ξέσπασμα μίας επιδημίας που εξαπλώνεται στο δίκτυο αλλά και μίας είδησης/φήμης, όπου ενημερώνεται το δίκτυο. Στην πρώτη περί- πτωση, μας ενδιαφέρει να περιορίσουμε την επιδημία, αλλάζοντας τοπολογικά το δίκτυο ενώ στη δεύτερη περίπτωση, είναι επιθυμητό να διευκολύνουμε την εξά- πλωση της είδησης, έτσι ώστε να ενημερωθούν όσο το δυνατόν, περισσότεροι κόμβοι(χρήστες). Η συμπεριφορά του δικτύου σε ένα τέτοιο φαινόμενο, μπορεί να προσομοιωθεί από ένα δυναμικό σύστημα. Με τον όρο δυναμικό σύστημα αναφερόμαστε σε ένα σύστημα που έχει ένα σύνολο καταστάσεων, όπου κάθε κατάσταση, προκύπτει σε συνάρτηση με την προηγούμενη. Παραδείγματα εφαρμογής ενός δυναμικού συστήματος σε δίκτυο, εμφανίζονται σε διάφορους τομείς όπως στην οικολογία, τη διάχυση πληροφορίας, το viral marketing, την επιδημιολογία. Τα δυναμικά συστήματα που προσομοιώνουν τη συμπεριφορά του δικτύου σε τέτοια φαινόμενα, χρησιμοποιούν επιδημιολογικά μοντέλα για να περιγρά- ψουν τις δυνατές καταστάσεις στις οποίες μπορεί να περιέλθει ένας κόμβος. Στη συγκεκριμένη εργασία, χρησιμοποιήσαμε το μοντέλο SIS (Susceptible-Infected-Susceptible) [8].Το μοντέλο SIS δηλώνει ότι ένας κόμβος μπορεί να είναι είτε επιρρεπής στο να ασθενήσει (susceptible) είτε ασθενής (infected). Αυτό σημαί- νει πως ένας κόμβος δεν θεραπεύεται ποτέ πλήρως αλλά υπάρχει πιθανότητα να ασθενήσει πάλι. Με βάση τη βιβλιογραφία, σε ένα τέτοιο δυναμικό σύστημα, αναζητούμε κά- ποια σημεία (fixed points) στα οποία το σύστημα θα ισορροπεί. Υπάρχουν σημεία τα οποία είναι σημεία ισορροπίας αλλά δεν είναι σταθερά. Σε αυτά τα σημεία, το σύστημα μπορεί στιγμιαία να ισορροπήσει αλλά ξεφεύγει πολύ εύκολα από αυτό. Αναζητούμε συνεπώς, σταθερά σημεία ισορροπίας, τα λεγόμενα stable fixed points. Έχει αποδειχτεί [6] ότι μπορούμε σε αυτά στα σημεία να καθορίσουμε τις απαραίτητες συνθήκες για να είναι σταθερά, περιορίζοντας τη μέγιστη ιδιοτιμή του μητρώου γειτνίασης που περιγράφει το δίκτυο. Ορίζονται δηλαδή κατώφλια (thresholds) κατά περίπτωση, που περιορίζουν την μέγιστη ιδιοτιμή του δικτύου με τέτοιο τρόπο ώστε το σύστημα, να βρίσκεται σε κατάσταση ισορροπίας. Στην πε- ρίπτωση που αναφερόμαστε στο φαινόμενο της επιδημίας, στόχος είναι στο αντί- στοιχο σημείο ισορροπίας η μέγιστη ιδιοτιμή να είναι κάτω του κατωφλίου, έτσι ώστε να εξασφαλίσουμε τον περιορισμό εξάπλωσης της επιδημίας στο δίκτυο. Στην περίπτωση που αναφερόμαστε σε μία είδηση ή ένα ανταγωνιστικό προϊόν, η μέγιστη ιδιοτιμή θέλουμε να είναι άνω του αντίστοιχου κατωφλίου έτσι ώστε να έχουμε εξάπλωση στο δίκτυο. Επομένως ανάλογα με την περίπτωση, αντιμε- τωπίζουμε διαφορετικά τα κατώφλια που υπολογίζονται για το αντίστοιχο σημείο ισορροπίας. Στα πλαίσια της μεταπτυχιακής εργασίας, χρησιμοποιήσαμε το μοντέλο SIS για να περιγράψουμε το φαινόμενο όπου ένας ιός εξαπλώνεται σε ένα δίκτυο όπου οι κόμβοι του δικτύου, έχουν διαφορετική ευαισθησία απέναντί του. Πραγματο- ποιήσαμε μαθηματική περιγραφή του μοντέλου, ορίζοντας τα απαραίτητα κατώ- φλια έτσι ώστε το σύστημα να ισορροπεί ανάλογα με το σημείο ισορροπίας αλλά και το είδος του γραφήματος. Επίσης, πραγματοποιήσαμε προσομοίωση του μο- ντέλου σε συνθετικά γραφήματα (κλίκα, αυθαίρετο γράφημα κ.α), επαληθεύοντας τη συμπεριφορά που υποδεικνύει το μαθηματικό μοντέλο. / Which is the appropriate answer about the definition of a network? One could answer that a group of people who share a relationship (colleagues, students etc) could be referred to, as a network. Another possible definition, is a computer network. Consequently, it is obvious that the idea of a network can be found in various ways in our daily life. In the same terms, suppose we have one competing idea/product or a virus that propagates over a multiple profile social (or other) network. Can we predict what proportion of the network will actually get ”infected” (e.g., spread the idea or buy the competing product), when the nodes of the network appear to have different sensitivity based on their profile? For example, if there are two profiles A, B in a network and the nodes of profile A and profile B are susceptible to a highly spreading virus with probabilities βA and βB respectively, what percentage of both profiles will actually get infected from the virus in the end? The behavior of such a network, can be simulated using dynamical systems theory. We consider a dynamical system as a system with a set of possible states where each future state, is computed based on the previous state. Dynamical System Applications, can be found in many fields such as viral marketing, ecology, information diffusion and virus propagation. In order to simulate the rumor or virus which is spreading across the network, one has to use virus propagation models. The selection of the appropriate model, depends on the special attributes and characteristics of the spreading rumor/virus and it should cover all the possible states in which a node in the network can be (sick, healthy,susceptible, informed, not informed etc). According to Dynamical Systems Theory, we are looking for possible fixed points where the system is in equilibrium. In particular, we would require each fixed point to be a stable attractor and not lead the system far away from the equilibrium point due to opposing forces (stable fixed points). It has been proven that limiting the leading eigenvalue of the adjacency matrix of the graph, is the only condition required, in order for the system to be in equilibrium state, in the corresponding fixed point. In this paper, we assume an SIS propagation model [8] which is applied on a heterogeneous network. That is, we assume that there is no fair game using the terminology of [14, 3]. In the SIS model, each node can be either in a susceptible (S) state or in the infected state (I) and as result there is no permanent immunity and every node can get infected multiple times.Since this is the first theoretical treatment of heterogeneous environments for virus propagation, we choose to work in the simple model of SIS and not in other models. Suppose that we are given a social network and a rumor that spreads over it, where the nodes of the network represent people with high/low sensitivity to the rumor and the links represent the association of the nodes, how will the rumor propagate over the network? That is, can we determine whether all members of the network will reproduce the rumor to their neighbors and ”infect” them or the rumor will spread in a small group in the network and die out quickly? Similarly, which is the tipping point where such a rumor or infectious virus will take off? It would be very helpful if we could find the specific point when the ”virus” spreads all over the network and an epidemic occurs. Finally, what is the case when the nodes have different endurance/sensitivity to the ”virus” and have temporary or permanent immunity? Our basic assumption and innovation when compared to all previous approaches is that there is no fair-play and nodes have different profile against the virus. That is, the network is heterogeneous with respect to the virus, which means that nodes have different sensitivity to it. This is one of our main contributions in comparison with previous results where all nodes appear to have the same behavior towards the virus and the same model parameters. The propagation model which is followed, resembles the SIS (no immunity like flu) model where nodes are either susceptible or infected but with modifications. All nodes can get infected from one another, despite the difference of their profiles. We prove and present the tipping point where the virus is about to spread all over the network or the rumor ”infect” every member of the network and result in a ”viral” phenomenon. Our main contribution, is that we provide answers for the questions above, for special topologies such as the clique as well as arbitrary graphs of high or low connectivity. In particular, to the best of our knowledge, we are the first to provide theoretical and experimental findings on the propagation of a virus over a heterogeneous network. We prove that in the case of two profiles, if one profile has high sensitivity to the virus and the other one has low sensitivity, actually nodes from both profiles will get infected proportionally in the case where the network is a clique. For arbitrary networks, we prove necessary conditions for the virus to die out allowing for multiple profiles (not just two), while at the same time we give directions to prove other interesting cases. The problem has many applications in the field of viral marketing, medicine, ecology and other.
269

Den svenska aidsepidemin : Ankomst, bemötande, innebörd / The Swedish AIDS Epidemic : Arrival, Response, and Meaning

Thorsén, David January 2013 (has links)
This dissertation investigates the public response to HIV/AIDS in Sweden in the 1980s and early 1990s. The analysis focuses on the National Commission on AIDS (NCA,“Aidsdelegationen”). The NCA was appointed by the government in 1985, led by the Minister of Social Affairs and mandated to initiate and coordinate the national response to the epidemic and in function until 1992. The dissertation’s theoretical framework is based on the understanding of an epidemic as a cultural and historical concept, emphasizing that health policy in the late twentieth century must be analyzed as a complex process of problematization.  The study includes four parts. The first part covers the years 1982 to 1985, an era characterized by small scale action, based mainly on voluntary initiatives with small resources. The second part examines the period 1985-1989, when the NCA formed an official national policy based on both strong legislation (enabling quarantine of recalcitrants, registration, contact tracing etc.) and massive nationwide information efforts (through mass media campaigns). This highly active phase was followed by a period of consolidation, from 1989 to 1992, examined in the third part of the study. This period included a new infectious disease act focused on HIV/AIDS as well as official campaigns with stronger focus on the individuals’ responsibility for their own health. In the last part, covering the years 1992-1996, I show how the HIV/AIDS problem was institutionalized as a disease and health topic alongside many others. The national campaigns continued through the 1990s, focusing on empowerment and individualization. As in many similar countries, the main aim of the Swedish strategy was to educate and encourage people to act with caution and responsibility towards themselves and their fellow citizens. In addition to this cooperation and inclusion approach, a strategy of contain and control was also implemented. This second strategy can, as I show, be explained by the strong connection made between HIV/AIDS and drug users. Through this connection, the Swedish drug policy had a decisive influence on the Swedish HIV/AIDS policy.
270

Logistic Growth Models for Estimating Vaccination Effects In Infectious Disease Transmission Experiments

Cai, Longyao 14 January 2013 (has links)
Veterinarians often perform controlled experiments in which they inoculate animals with infectious diseases. They then monitor the transmission process in infected animals. The aim of such experiments can be to assess vaccine effects. The fitting of individual-level models (ILMs) to the infectious disease data, typically achieved by means of Markov Chain Monte Carlo (MCMC) methods, can be computationally burdensome. Here, we want to see if a vaccination effect can be identified using simpler regression-type models rather than the complex infectious disease models. We examine the use of various logistic growth curve models, via a series of simulated experiments in which the underlying true model is a mechanistic model of infectious disease spread. We want to investigate whether a vaccination effect can be identified when only partial epidemic curves are observed, and to assess the performance of these models when experiments are run with various sets of observational times.

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