Dynamics of quantum-dot mode-locked lasers with optical injection

We present the dynamics of quantum-dot passively mode-locked semiconductor lasers under optical injection. We discuss the benefits of various configurations of the master source including single, dual, and multiple coherent frequency sources. In particular, we demonstrate that optical injection can improve the properties of the slave laser in terms of time-bandwidth product, optical linewidth, and timing jitter.

Mode-locked semiconductor lasers with optical injection

We perform characterization of the pulse shape and noise properties of quantum dot passively mode-locked lasers (PMLLs). We propose a novel method to determine the RF linewidth and timing jitter, applicable to high repetition rate PMLLs, through the dependence of modal linewidth on the mode number. Complex electric field measurements show asymmetric pulses with parabolic phase close to threshold, with the appearance of waveform instabilities at higher currents. We demonstrate that the waveform instabilities can be overcome through optical injection-locking to the continues wave (CW) master laser, leading to time-bandwidth product (TBP) improvement, spectral narrowing, and spectral tunability. We discuss the benefits of single- and dual-tone master sources and demonstrate that dual-tone optical injection can additionally improve the noise properties of the slave laser with RF linewidth reduction below instrument limits (1 kHz) and integrated timing jitter values below 300 fs. Dual-tone injection allowed slave laser repetition rate control over a 25 MHz range with reduction of all modal optical linewidths to the master source linewidth, demonstrating phase-locking of all slave modes and coherence improvement.

Mode-locked semiconductor lasers with optical injection

We perform characterization of the pulse shape and noise properties of quantum dot passively mode-locked lasers (PMLLs). We propose a novel method to determine the RF linewidth and timing jitter, applicable to high repetition rate PMLLs, through the dependence of modal linewidth on the mode number. Complex electric field measurements show asymmetric pulses with parabolic phase close to threshold, with the appearance of waveform instabilities at higher currents. We demonstrate that the waveform instabilities can be overcome through optical injection-locking to the continues wave (CW) master laser, leading to time-bandwidth product (TBP) improvement, spectral narrowing, and spectral tunability. We discuss the benefits of single- and dual-tone master sources and demonstrate that dual-tone optical injection can additionally improve the noise properties of the slave laser with RF linewidth reduction below instrument limits (1 kHz) and integrated timing jitter values below 300 fs. Dual-tone injection allowed slave laser repetition rate control over a 25 MHz range with reduction of all modal optical linewidths to the master source linewidth, demonstrating phase-locking of all slave modes and coherence improvement.

Ankyrin is the major oxidised protein in erythrocyte membranes from end-stage renal disease patients on chronic haemodialysis and oxidation is decreased by dialysis and vitamin C supplementation

Chronically haemodialysed end-stage renal disease patients are at high risk of morbidity arising from complications of dialysis, the underlying pathology that has led to renal disease and the complex pathology of chronic kidney disease. Anaemia is commonplace and its origins are multifactorial, involving reduced renal erythropoietin production, accumulation of uremic toxins and an increase in erythrocyte fragility. Oxidative damage is a common risk factor in renal disease and its co-morbidities and is known to cause erythrocyte fragility. Therefore, we have investigated the hypothesis that specific erythrocyte membrane proteins are more oxidised in end-stage renal disease patients and that vitamin C supplementation can ameliorate membrane protein oxidation. Eleven patients and 15 control subjects were recruited to the study. Patients were supplemented with 2 × 500 mg vitamin C per day for 4 weeks. Erythrocyte membrane proteins were prepared pre- and post-vitamin C supplementation for determination of protein oxidation. Total protein carbonyls were reduced by vitamin C supplementation but not by dialysis when investigated by enzyme linked immunosorbent assay. Using a western blot to detect oxidised proteins, one protein band, later identified as containing ankyrin, was found to be oxidised in patients but not controls and was reduced significantly by 60% in all patients after dialysis and by 20% after vitamin C treatment pre-dialysis. Ankyrin oxidation analysis may be useful in a stratified medicines approach as a possible marker to identify requirements for intervention in dialysis patients.

Dynamics of quantum-dot mode-locked lasers with optical injection

We present the dynamics of quantum-dot passively mode-locked semiconductor lasers under optical injection. We discuss the benefits of various configurations of the master source including single, dual, and multiple coherent frequency sources. In particular, we demonstrate that optical injection can improve the properties of the slave laser in terms of time-bandwidth product, optical linewidth, and timing jitter.

"And a child shall lead them?": Slavery, childhood, and African cultural identity in Jamaica, 1750--1838

Based primarily on archival evidence collected in Jamaica, this dissertation examined the nature of childhood in the plantation complex between 1750 and 1838, how colonial society and the slave community defined childhood, and how that definition changed over time. It proves how childhood and slavery influenced and changed each other during these years, with the abolitionist movement standing as the main catalyst for change. Although this project chronologically examined the changing nature of slave childhood in Jamaica through four shifts of Jamaican history, each chapter topically focused on slave childhood through the lenses of labor, family, resistance, race, status, culture, education, and freedom. ^ The research showed that although slavery forced slave children into an early adulthood, childhood was a contested process that changed with each generation of children. As the abolitionist movement motivated changes in planter opinion on the value of children to the plantation economy, planters placed increased responsibility on slave children to lead them towards economic stability and profitability. Meanwhile, slave children struggled to survive slavery by reinventing and modifying their ideas of family and kinship and reacting to their situation through various acts of resistance. Although slave parents gained many opportunities to raise their children on their own terms, they struggled to maintain control over that process as planters attempted to change the nature of African cultural identity in Jamaica by impressing Christian and English values on slave children. Under apprenticeship, childhood returned to its previous status as a liability in the eyes of the Jamaican planters. Yet, Jamaican children faced the prospect of an unwritten childhood, one that was free from planter control and gave Jamaican laborers hope for the future. In the end, this dissertation told the story of an overlooked childhood, one that was often defined by Jamaican planters, but frequently contested by the slaves themselves. ^

El discurso del poder y la lucha de contrarios en la narrativa de la esclavitud en Cuba y Estados Unidos

This dissertation explores the behavior of prejudiced discourse in the most representative narratives against inhumane slavery written in Cuba and the United States in the nineteenth century: Autobiografía de un esclavo, by Juan Francisco Manzano; Francisco, by Anselmo Suárez y Romero; Narrative of the Life of Frederick Douglass, an American Slave, by Frederick Douglass; and Uncle Tom's Cabin, by Harriett Beecher Stowe. This study deals with the identification between race and slavery that occurred in the American continent, using racial prejudice to justify the enslavement of human beings. Such concepts were maintained, diffused and perpetuated by the dominant discourse. ^ In the nineteenth century, intellectuals from both Cuba and the United States were highly influenced by the modern philosophical ideas rooted in the European Enlightenment. These ideas contradicted by principle the "peculiar institution" of slavery, which supported a great deal of the economy of both nations. This conflict of principles was soon reflected in literature and led to the founding of Cuban and African-American narrative respectively. The common exposure to slavery brought together two nations otherwise highly dissimilar in historical and cultural circumstances. Based on the theories of discourse by Foucault, Terdiman, and van Dijk, the analysis of the discourse displayed in these literary works helps understand how discourse is utilized to subvert the dominant discourse without being expelled or excluded by it. This subversion was successfully accomplished in the American narratives, while only attempted in the Cuban works, given Cuba's colonial status and the compromised economic loyalties of the Delmontino cenacle which produced these works. ^

Adaptive fault-tolerant teleoperation

While the robots gradually become a part of our daily lives, they already play vital roles in many critical operations. Some of these critical tasks include surgeries, battlefield operations, and tasks that take place in hazardous environments or distant locations such as space missions. ^ In most of these tasks, remotely controlled robots are used instead of autonomous robots. This special area of robotics is called teleoperation. Teleoperation systems must be reliable when used in critical tasks; hence, all of the subsystems must be dependable even under a subsystem or communication line failure. ^ These systems are categorized as unilateral or bilateral teleoperation. A special type of bilateral teleoperation is described as force-reflecting teleoperation, which is further investigated as limited- and unlimited-workspace teleoperation. ^ Teleoperation systems configured in this study are tested both in numerical simulations and experiments. A new method, Virtual Rapid Robot Prototyping, is introduced to create system models rapidly and accurately. This method is then extended to configure experimental setups with actual master systems working with system models of the slave robots accompanied with virtual reality screens as well as the actual slaves. Fault-tolerant design and modeling of the master and slave systems are also addressed at different levels to prevent subsystem failure. ^ Teleoperation controllers are designed to compensate for instabilities due to communication time delays. Modifications to the existing controllers are proposed to configure a controller that is reliable in communication line failures. Position/force controllers are also introduced for master and/or slave robots. Later, controller architecture changes are discussed in order to make these controllers dependable even in systems experiencing communication problems. ^ The customary and proposed controllers for teleoperation systems are tested in numerical simulations on single- and multi-DOF teleoperation systems. Experimental studies are then conducted on seven different systems that included limited- and unlimited-workspace teleoperation to verify and improve simulation studies. ^ Experiments of the proposed controllers were successful relative to the customary controllers. Overall, by employing the fault-tolerance features and the proposed controllers, a more reliable teleoperation system is possible to design and configure which allows these systems to be used in a wider range of critical missions. ^

Adaptive Fault-Tolerant Teleoperation

While the robots gradually become a part of our daily lives, they already play vital roles in many critical operations. Some of these critical tasks include surgeries, battlefield operations, and tasks that take place in hazardous environments or distant locations such as space missions. In most of these tasks, remotely controlled robots are used instead of autonomous robots. This special area of robotics is called teleoperation. Teleoperation systems must be reliable when used in critical tasks; hence, all of the subsystems must be dependable even under a subsystem or communication line failure. These systems are categorized as unilateral or bilateral teleoperation. A special type of bilateral teleoperation is described as force-reflecting teleoperation, which is further investigated as limited- and unlimited-workspace teleoperation. Teleoperation systems configured in this study are tested both in numerical simulations and experiments. A new method, Virtual Rapid Robot Prototyping, is introduced to create system models rapidly and accurately. This method is then extended to configure experimental setups with actual master systems working with system models of the slave robots accompanied with virtual reality screens as well as the actual slaves. Fault-tolerant design and modeling of the master and slave systems are also addressed at different levels to prevent subsystem failure. Teleoperation controllers are designed to compensate for instabilities due to communication time delays. Modifications to the existing controllers are proposed to configure a controller that is reliable in communication line failures. Position/force controllers are also introduced for master and/or slave robots. Later, controller architecture changes are discussed in order to make these controllers dependable even in systems experiencing communication problems. The customary and proposed controllers for teleoperation systems are tested in numerical simulations on single- and multi-DOF teleoperation systems. Experimental studies are then conducted on seven different systems that included limited- and unlimited-workspace teleoperation to verify and improve simulation studies. Experiments of the proposed controllers were successful relative to the customary controllers. Overall, by employing the fault-tolerance features and the proposed controllers, a more reliable teleoperation system is possible to design and configure which allows these systems to be used in a wider range of critical missions.

Atlantic Ais in the Sixteenth and Seventeenth Centuries: Maritime Adaptation, Indigenous Wrecking, and Buccaneer Raids on Florida’s Central East Coast

The Ais were a Native American group who lived along the Atlantic shoreline of Florida south of Cape Canaveral. This coastal population’s position adjacent to a major shipping route afforded them numerous encounters with the Atlantic world that linked Europe, Africa, the Caribbean, and the Americas. Through their exploitation of the goods and peoples from the European shipwrecks thrown ashore, coupled with their careful manipulation of other Atlantic contacts, the Ais polity established an influential domain in central east Florida during the sixteenth and seventeenth centuries. The pre-contact peoples of Florida’s east coast, including the ancestors of the Ais, practiced a maritime adaptation concentrated on the exploitation of their bountiful riverine, estuarine, and marine environments. The Ais then modified their maritime skills to cope with the opportunities and challenges that accompanied European contact. Using their existing aquatic abilities, they ably salvaged goods and castaways from the Spanish, French, English, and Dutch vessels dashed on the rocks and reefs of Florida’s coast. The Ais’ strategic redistribution of these materials and peoples to other Florida Native Americans, the Spaniards of St. Augustine, and other passing Europeans gained them greater influence. This process, which I call indigenous wrecking, enabled the Ais to expand their domain on the peninsula. Coastal Florida Native Americans’ maritime abilities also attracted the attention of Europeans. In the late seventeenth century, English buccaneers and salvagers raided Florida’s east coast to capture indigenous divers, whom they sent to work the wreck of a sunken Spanish treasure ship located in the Bahamas. The English subsequently sold the surviving Native American captives to other Caribbean slave markets. Despite population losses to such raids, the Ais and other peoples of the east coast thrived on Atlantic exchange and used their existing maritime adaptation to resist colonial intrusions until the start of the eighteenth century. This dissertation thus offers a narrative about Native Americans and the Atlantic that is unlike most Southeastern Indian stories. The Ais used their maritime adaptation and the process of indigenous wrecking to engage and exploit the arriving Atlantic world. In the contact era, the Ais truly became Atlantic Ais.

The Saints of Banias

THE SAINTS OF BANIAS is a novel set in a fictional slavetown during the Reconstruction Era. The work seeks to blend myth, magic, and history to create a world that is both believable and otherworldly. The novel follows Beah, an ex-slave girl travelling to the town of Banias in hopes of finding her mother; Prophet Moon, an itinerant vision-seer who offers to help Beah with her goal; and the founder of the town, Claude Banias, who struggles to protect Banias from bloodthirsty radicals. As the characters’ lives intertwine, they face more challenges and secrets. THE SAINTS OF BANIAS is loosely based on the biblical story of David and Bathsheba, with Claude acting as David, Beah as Bathsheba, and Prophet Moon as a hybrid of Nathan and Uriah. The novel primarily explores destructive love, the value of hope, and the price of preserving a culture.

Entre missas e batuques: Irmandade de Nossa Senhora do Rosário dos Homens Pretos em Recife, Goiana e Olinda - Século XVIII

This work is a comparative study of three black brotherhoods that existed in Pernambuco in the eighteenth century, it is the Brotherhood of Our Lady of the Rosary of Black Men of Recife, Olinda and Goiás. The goal was to understand the similarities and differences between them, taking as benchmark their operating statutes, called Appointments. From the data analysis of the commitments associated with other documents produced by the Brotherhoods and the administrative and religious authorities, we sought the social profile of the villages in evidence, as well as the participation of black people inside. We sought to understand the historical conditions of that period, from the fact that the slave society, the black was placed in a position of subordination. However, as a carrier element of culture, although this condition, was able to overcome social obstacles, opening possibilities for own cultural manifestations of his group could occur. The coexistence in the Brotherhoods of the Rosary, which in addition to organizations for mutual assistance within the Catholic religion, is also constituted as fields mediators between high culture and popular culture, made those organizations become social spaces and representation allowed the existing order. The Brotherhoods of the Rosary in Recife, Olinda and Goiás, had their own hierarchical logic that engendered the construction of new black identities marked by cultural circularity that became possible due to the Atlantic diaspora process

As raízes históricas da política criminal na legislação e nas práticas de atendimento ao adolescente em conflito com a lei

This thesis investigates the historical influence of the criminal policy in the context that shapes the first specific law for children and adolescents in Brazil, the 1927 Children's Code, a standard that inaugurates the conceptual scission between children and "minor" and their different treatment by the State. The study addresses the demand for order in the context of changes in the working world in the transition from the slave system to the capitalist mode of production, and the corresponding disciplinary and punitive control mechanisms directed to the segment of childhood and adolescence. The theoretical route proposes a questioning of the political construction of law and justice, as well as the conformation of the punitive techniques, and the construction of the stereotype of the "delinquent", prime target of the criminal policy, focusing on the process of criminalization of the segment in question through the confrontation of the Critical perspective with the approaches of Classical and Positive schools. This research shows the imposition of a bourgeois morality that obscures the social conflict attributing it to people isolated by the criminalization of their conduct; and points out that the historical forms of selective social control were greatly influenced by psychiatry and psychology, either by the elaboration of the image of the "delinquent" or by the expected performance of custodial institutions. Finally, the developments and the permanence of the historical roots of the criminal policy are problematized, relating them to the difficulties currently encountered in the consolidation of the legal garantism paradigm proposed by the Children and Adolescent Statute.

As raízes históricas da política criminal na legislação e nas práticas de atendimento ao adolescente em conflito com a lei

This thesis investigates the historical influence of the criminal policy in the context that shapes the first specific law for children and adolescents in Brazil, the 1927 Children's Code, a standard that inaugurates the conceptual scission between children and "minor" and their different treatment by the State. The study addresses the demand for order in the context of changes in the working world in the transition from the slave system to the capitalist mode of production, and the corresponding disciplinary and punitive control mechanisms directed to the segment of childhood and adolescence. The theoretical route proposes a questioning of the political construction of law and justice, as well as the conformation of the punitive techniques, and the construction of the stereotype of the "delinquent", prime target of the criminal policy, focusing on the process of criminalization of the segment in question through the confrontation of the Critical perspective with the approaches of Classical and Positive schools. This research shows the imposition of a bourgeois morality that obscures the social conflict attributing it to people isolated by the criminalization of their conduct; and points out that the historical forms of selective social control were greatly influenced by psychiatry and psychology, either by the elaboration of the image of the "delinquent" or by the expected performance of custodial institutions. Finally, the developments and the permanence of the historical roots of the criminal policy are problematized, relating them to the difficulties currently encountered in the consolidation of the legal garantism paradigm proposed by the Children and Adolescent Statute.

Entre as tramas da indústria da moda: argumentos sobre o trabalho escravo contemporâneo na sociedade de consumo

Even after its abolition, the slave labor still exists in the world. In a new socio-historic context, the shackles and slave quarters have been left behind, nowadays the workers are tempted, subjected to degrading conditions and have their rights retrenched. The contemporary slave labor has been emerging as subject of research in the Organizational Studies since the early 2000s, calling attention to many gaps to be filled about the way organizations all around the world use this practice. Contemporary slave labor is found in many and various economic activities, since coal to textile industries or even stores. In this dissertation, we have incorporated the consumption dimension to the field of Organizational Studies, discussing the modern slavery, aiming to understand the consumers’ point of view about this topic, that is, we have researched the consumers’ interpretations concerning the slave labor in the fashion industry. Our objective is to analyze consumer’s argumentative construction in the decision of buying or not products made by industries from the fashion field that were denounced because of slave labor usage. We have adopted fashion industry as research focus because it obscures the reflection of the consumers that feel like in a new world while shopping, a world of beauty and fantasy, seeking their own satisfaction. Furthermore, the Brazilian fashion industry is one of the biggest of the world (ABIT, 2015), with a huge symbolic strength in the country. We have realized a qualitative research using semi-structured interviews with 35 consumers to identify their arguments according to the criteria defined by Liakopoulos (2002): data, propositions, guarantees, supports and refutations. The data are the statements used by the interviewees categorically, that is, those which are clear in the interviews. The propositions are what qualifies and justifies the used data. The guarantees are related to the nature of the data, they are what gives the sense to the data and are introduced implicitly in the interviewee speech. The supports are universal premises introduced in order to legitimate the arguments. The refutations, when present, counter the used arguments. As results, we’ve found consumers who developed arguments pro-consumption and anti-consumption and who have defended ideas about the responsibility of different actors for the existence of this practice and for the fight against it. From these two categories: (1) pro-consumption – consume despite the complaints and (2) anti-consumption – don’t consume, because of the accusations; we have identified the following argumentative lines: skepticism, faultfinding and moral engagement. By the end, we have presented the interviewees’ argumentative construction and the obtained results.