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Introdução: As funções cognitivas sofrem influência da idade, tanto no seu desenvolvimento como no seu declínio. De forma geral, as medidas de inteligência se relacionam com o volume de substância cinzenta (SC) em áreas cerebrais específicas e sofrem influência com o processo de envelhecimento. Em crianças e adolescentes as áreas envolvidas são o córtex pré-frontal, enquanto nos idosos e adultos jovens os córtices frontais e temporais desempenham um papel importante. Objetivo: Identificar quais áreas cerebrais estão implicadas nas variações das medidas de inteligência em uma amostra representativa de adultos jovens e idosos saudáveis. As hipóteses principais são: 1) haverá uma associação indireta entre distribuição de SC e idade envolvendo áreas de córtex frontal e temporal; 2) em adultos, as medidas de QI estimado irão se mostrar estáveis em decorrência da estabilidade entre as funções de inteligência fluida e cristalizada; 3) em idosos, as medidas de QI estimado apresentarão correlação direta com a distribuição de SC envolvendo o córtex temporal e límbico; 4) em idosos, as medidas de inteligência fluida apresentarão correlação direta com a distribuição de SC em córtices frontal e pré-frontal; 5) em idosos, as medidas de inteligência cristalizada não apresentarão correlações significativas com a distribuição de SC. Metodologia: Os exames de imagens cerebrais foram obtidos a partir de uma amostra representativa com ampla faixa etária. Foi investigada uma amostra de 258 sujeitos entre 18 e 75 anos que preencheram os critérios de inclusão/exclusão, e para os quais é possível estimar o QI através de subtestes do WASI. Os resultados estatísticos de cada análise foram realizados utilizando a volumetria baseada em voxel sob a forma de mapas paramétricos estatísticos e a relação dos resultados foram somente os que sobreviveram a correção para comparações múltiplas. Todos os resultados foram corrigidos através das variáveis de confusão (protocolo,aparelho de ressonância magnética e volume cerebral). Resultados: Identificamos correlações entre QI estimado e de inteligência fluida em regiões temporais mediais e límbicas bilaterais, na população idosa. Na população adulta também identificamos correlações entre inteligência cristalizada envolvendo regiões frontais e pré-frontais direita. Observamos também que houve perda de SC na população adulta envolvendo as regiões pré-frontais e frontais à esquerda. Conclusão: As medidas de inteligência cristalizada e fluida apresentaram correlação direta com o volume cerebral total, e especificamente em córtices frontais, pré-frontais bilaterais, e em regiões temporais e límbicas / Introduction: The cognitive functions could be influenced by age, both during the development as well as during the decline. Measures of intelligence in general are related to the volume of gray matter (GM) in specific brain areas, and also are under influence of aging process. In children and adolescents the brain areas involved is mainly the prefrontal cortex, while in the elderly other areas, such as the frontal and temporal cortices play an important role. Objective: To identify which brain areas are involved in variations in intelligence measures in a representative sample of large age span, from young adults to healthy elderly. The main hypotheses are: 1) there would be an indirect association between age distribution of GM and surrounding areas of the frontal and temporal cortex, 2) in adults, estimated IQ measures would prove to be stable secondarily to adaptation between fluid intelligence and crystallized functions, 3) in the elderly, measures of IQ estimated would present direct correlation with the distribution of GM involving the temporal cortex and limbic, 4) in the elderly, measures of fluid intelligence would show a direct correlation with the distribution of GM and pre frontal cortices, 5) in the elderly, measures of crystallized intelligence would not present significant correlations with the distribution of GM. Methods: Brain images scans were obtained from a representative sample with large age span. We investigated a sample of 258 subjects between 18 and 75 who met the criteria for inclusion / exclusion, and for which it is possible to estimate the IQ subtests by the WASI. Correlation statistical analyses were performed using voxel-based methodology with Statistical Parametric Map Software, and reported only if survived multiple comparison correction. All results were corrected for confounding variables (protocol, MRI scan and total brain volume). Results: We identified correlations between IQ and estimated fluid intelligence in medial temporal and limbic regions bilateral in the elderly. In the adult population we also identified correlations between crystallized intelligence involving the frontal and prefrontal right. We also observed that there was loss of GM in adults involving the left prefrontal regions and frontal. Conclusion: Measures of fluid and crystallized intelligence showed direct correlation with the total brain volume, and specifically in the frontal cortex, bilateral prefrontal, and temporal and limbic regions

Pas de résumé en français / Being compared with oxide glasses, chalcogenide glasses have fine infrared transmissivity and higher optical nonlinearity, and also could be drawn into optical fibers. So chalcogenide glasses and fibers have potential wide applications in the fields of all-optical information processing, infrared lasers, nonlinear optical devices, and so on, the studies of their optical nonlinearity are one of the attractive subjects in the area of optoelectronics at present. The main purpose of this paper is to improve the stability and enhance the intensity of nonlinearity in chalcogenide glasses and fibers by means of exploring new glass compositions, optimizing the external field poling method, designing and fabricating fibers with special structures, all of these will promote their real applications. The main results are concluded as follows . The glass-forming region of GeS2-GA2S3-AgX (X=Cl, Br, I) and GeS2-Ga (In)2S3-CuI systems were determined , the maximal content of the additive halides are 70% and 12% respectively. In both two systems glasses, with the increasing addition of halides, the thermal stability reduce, density and linear refractive index increase, the ultraviolet cut-off edges shift to longer wavelength, while the infrared cut-off edges keep almost the same. 30GeS2 35Ga2S3 35AgCl and 47.5GeS2 17.5Ga2S3 35AgCl surface- and bulk-crystallized glasses that contain AgGaGeS4 nonlinear optical crystallites were prepared. Obvious second harmonic generation (SHG) could be observed in these crystallized glasses, and their intensity relate to the distribution and size of the precipitated AgGaGeS4 crystals, the maximal second-order nonlinearity coefficients is as high as 12.4pm/V. These crystallized glasses have good chemical and SHG stability. For GeS2-Ga (In)2S3-CuI systems glasses, due to their small glass-forming region, they are not suit for the preparation of crystallized glasses that contain CuGaS2 or CuInS2 nonlinear optical crystals. According to the structural studies of two system glasses, the main structural units of theses glasses are [YS4-xXx] (Y=Ge, Ga, In. X=Cl, Br, I) mixed anion tetrahedrons, they form a three-dimensional glassy network through bridging sulphur bonds. When the contents of halides MX(M=Ag, Cu. X=Cl, Br, I) are low, some [XxS3-xGe(Ga)S3-xXx] (X=Cl, Br, I) mixed ethane-like structural units exist in the glass network, and they will gradually transform to [YS4-xXx] (Y=Ge, Ga, In. X=Cl, Br, I) mixed anion tetrahedrons with the increasing content of halides, till totally disappear. Both two system glasses have ultrafast (~150fs) third-order optical nonlinearity and reverse saturation absorption, they belong to self-focusing medium. The third-order optical nonlinearity mainly originate from the distortion of electron cloud of Y-X (Y=Ge, Ga, In, X=Cl, Br, I, S) bonds in the structural units. For GeS2-GA2S3-AgX (X=Cl, Br, I) system glasses, the largest nonlinear susceptibility n2 is 10.50x10-18 m/W, the smallest figure of merit (FOM) is 0.606. In addition, the relation of n2 with n0 do not obey Miller’s rule, but in accordance with the structural variation. Among the glass compositions with different additive halogens, Br-containing glasses have relatively best third-order nonlinearities. For GeS2-Ga (In)2S3-CuI system glasses, the largest nonlinear susceptibility n2 is 9.37x10-18 m/W, the smallest figure of merit (FOM) is 2.237. High purity AS2S3 glass performs and low loss single index fibers with diameter of 100~400µm that drawn form these performs were prepared, the transmission losses between 2~6 µm is only 0.5dB/m. AS2S3 tapered fibers have a uniform diameter of taper wasit, fine surface smoothness, and sharp taper transition part.

<p>The ferrimagnetic electrical insulator yttrium iron garnet (YIG) has been proved a promising magnonic platform that allows for a variety of application within microwave fre- quency range. This dissertation focuses on the development of novel spin wave resonators and filters for next-generation radio frequency technology.</p> <p>Chapter 1 begins with an introduction to modern radio frequency communication tech- nology and motivation of our research on novel radio frequency devices.</p> <p>Chapter 2 discusses about the properties of yttrium iron garnet (YIG) thin film platform and theory of magnetostatic waves (MSW) within the magnetic thin film system. Three different types of magnetostatic wave modes, known as magnetostatic forward volume wave (MSFVW), magnetostatic backward volume waves (MSBVW) and magnetostatic surface wave (MSSW), are illustrated in this section. They have very distinct dispersion relations and require different transduction technology, which leads to disparate designs for devices utilizing different modes. The damping mechanism and linewidth of the magnetostatic modes will also be discussed in this chapter.</p> <p>Chapter 3 will showcase a new YIG-on-Si platform created using novel YIG bonding technology and the first ever on-chip MSFVW hairpin resonator on the YIG-on-Si platform. In the first part, we would like to show finite element analysis of YIG-on-Si MSFVW hairpin resonator and prove the capability of the hairpin transducer incorporated with YIG thin film to yield lower self-inductance and stronger excitation field. These unique properties are beneficial for generating high coupling between magnon and microwave domains. In the following sections, the bonding technology essential for creation of YIG-on-Si platform and key fabrication technology of hairpin devices are explained in detailed. With well defined fabrication process established, we will demonstrate that the hairpin magnetostatic wave resonator obtained through the process is magnetically tunable with a high coupling efficiency over 50%. An out-of-plane Z-directional tunable magnetic field results in forward volume spin-wave resonance with frequency in the 5G band. This technology enables us to build on-chip devices of desirable high coupling and magnetic tuning on the new YIG-on-Insulator platform and provides possibility of magnetic tuning and band-pass filter at radio-frequency range.</p> <p>Chapter 4 demonstrates a planar monolithic yttrium iron garnet (YIG) Chebyshev bandstop filter on traditional gadolinium gallium garnet (GGG) substrate with tunable frequency, low insertion loss and high rejection. This filter is created in YIG micro-machining technol- ogy that allows direct placement of metal transducers on YIG for strong spin-wave coupling. With an out-of-plane 3900 Oe bias field, the bandstop filter exhibits 55 dB maximum stop- band rejection at a center frequency of 6 GHz, with 2 dB passband insertion loss and 37.8 dBm passband <strong>IIP3</strong>. By applying different bias fields, the stopband center frequency is tuned from 4 GHz to 8 GHz while maintaining more than 30 dB rejection. Incorporated with proper design of tunable compact electromagnet, this new filter design can provide attenuation of spurs appearing across the 5G and X-band spectrum.</p> <p>In chapter 5, we will explore the properties of YIG thin-film materials in depth. Both YIG-on-Si and YIG-on-GGG platform under different conditions will be examined. Results of X-ray diffraction (XRD), ferromagnetic resonance (FMR), scanning tunneling microscope (STM) on the YIG thin films will be presented. Those results will cast light onto the study of limiting factors of our YIG-on-Si and YIG-on-GGG devices.</p>

Organisationer behöver kvalificerad personal för att fungera effektivt och därmed blir rekrytering en viktig aktivitet. Det är också angeläget att ny personal anpassar sig väl till arbetsförhållandena. Syftet med denna avhandling var att tydliggöra möjligheterna att genom urval bidra till en långsiktigt hållbar rekrytering för organisation, individ och samhälle. Avhandlingen omfattar tre delstudier och baseras på data från rekrytering av nya poliser i Sverige. En kohort har följts från urvalet av de sökande till polisutbildningen våren 2008 (N = 1 344) över tre uppföljningstillfällen (N = 717–729), nämligen vid slutet av två års polisutbildning, vid slutet av sex månaders aspirantutbildning och vid slutet av det första anställningsåret. Studie I syftade till att undersöka möjligheterna att välja ut de sökande som är mest lämpade att bli poliser genom att kombinera information från flera urvalsmetoder. Vanligtvis används intervjuer för att i slutet av urvalsprocessen välja ut de mest lämpade kandidaterna. Analyser med flera kriterier på framgångsrik rekrytering (prestation, tillfredsställelse med utbildning respektive arbete, vilja att stanna i yrket och hälsa) vid de tre uppföljningstillfällen, visade att ett alternativt förfarande – att kombinera information från urvalsmetoder som i tidigare steg använts för att sålla bort olämpliga sökande – hade högre prognosförmåga. Det handlade om information från begåvningstest, personlighetstest och konditionstest. Ett sådant förfarande kan också vara mer tillförlitligt och resurseffektivt. Vid urval av poliser bör intervjuer däremot främst ses som ett verktyg för att sålla bort olämpliga kandidater. Studie II syftade till att öka förståelsen för hur resultat från begåvningstest ska tolkas och användas vid urval. För de flesta yrken, inklusive polisyrket, har begåvningstest visats vara en av de urvalsmetoder som bäst predicerar prestation. Det har förklarats med effekter av generell begåvning. Resultaten från Studie II visade dock att utöver generell begåvning kan också en verbal och kunskapsladdad komponent antas viktig för att predicera prestation. Samtidigt gav studien stöd för att vid urval använda en samlad totalpoäng från begåvningstest. Studie III syftade till att undersöka den relativa betydelsen av urvalsfaktorer som personlighet och begåvning respektive den psykosociala arbetsmiljön för nya polisers arbetsrelaterade attityder och hälsa efter det första anställningsåret. Studien visade att arbetsmiljöfaktorer, såsom möjligheter till utveckling och återkoppling i arbetet samt rimlig arbets­belastning, var betydligt viktigare än urvalsfaktorer för nya polisers anpassning till arbetsförhållandena i yrket. Sammanfattningsvis visar föreliggande avhandling att det är meningsfullt att över tid beakta flera kriterier på framgångsrik rekrytering. Den visar också att information från flera urvalsmetoder bör kombineras för att välja ut de mest lämpade kandidaterna. Vidare visar avhandlingen på värdet av att använda verbalt laddade begåvningstest vid urval. Förmågan att predicera framgång i polisyrket med olika urvalsmetoder är dock måttlig. Avhandlingen visar däremot att arbetsförhållandena för ny personal kan ha avgörande betydelse. Det betyder att organisationer som strävar efter hållbar rekrytering bör prioritera både urval och sunda arbetsförhållanden för ny personal. Det gäller inte minst polisorganisationer där kostnaderna för rekrytering är höga. / Organizations need qualified personnel to work effectively. Accordingly recruitment is an important organizational activity. Moreover, to attain sustainability for organizations, individuals, and the society, it is assumed important that new personnel adjust well to their working conditions. The aim of this thesis was to investigate the role of selection for long-term sustainable recruitment. The thesis includes three studies based on data from the recruitment of new police officers in Sweden. A cohort of new police officers was followed from the end of the admittance process to the basic police training program in spring 2008 (N = 1,344) and then at three consecutive follow-ups (N = 717-729), 1) at the end of two years of academy training, 2) at the end of six months of field training, and 3) at the end of the first working year. Study I aimed to further the understanding of how to select suitable police applicants by using combinations of common selection methods. Analyses of several criteria (performance, satisfaction, occupational retention, and health) at the three follow-ups suggest that combining information from cognitive, personality, and physical fitness tests, that in earlier hurdles have been used to screen out unsuitable applicants, would be useful in identifying the most suitable candidates, while interviews may primarily be considered as a tool for screening out any unsuitable ones. Study II focused on how to interpret and make use of results from cognitive tests in applied settings such as selection. In most occupations, including the police, cognitive tests are among the most valid predictors of performance. This has been explained by the influence of general intelligence. However, the results from Study II showed that beyond general intelligence, a verbal and knowledge loaded component can be important in predicting performance. Also, the study supported the use of total scores in selection. Study III aimed to examine the relative importance of selection factors (e.g., personality and general intelligence) and psychosocial working conditions for new police officers’ work-related attitudes and health. The study showed that psychosocial working conditions, such as opportunities for development and feedback as well as a balanced workload, were far more important than selection factors for the new police officers’ adjustment to their occupation. Taken together, the thesis shows the value of considering several time points and several criteria of successful recruitment. Also, it demonstrates the usefulness of combining information from several selection methods to select the most suitable candidates, along with the value of using verbally loaded cognitive tests in selection. Still, the ability to predict success among police officers by using selection methods remains modest. Additionally, the thesis shows that the working conditions for new personnel can be considered crucial if recruitment is seen as a long-term process that also includes the introduction phase. Accordingly, organizations striving for sustainable recruitment need to focus on developing sound selection processes and providing sound working conditions for their new personnel. This is of particular importance for organizations such as the police, where the costs of recruitment are high. / <p>At the time of the doctoral defense, the following papers was unpublished and had a status as follows: Paper 3: Manuscript.</p>