Mobility of General Managers as Lodging Size, Service Vary

Hotel Managerment has usually been viewed as a single labor market which allows considerable movement between properties of different sizes and service levels. The authors question this assumption and support the hypothesis that general managers in one type of hotel will have spent a large majority of their careers in hotels of the same type.

The effects of school mobility in pre -assessment grade levels on student performance and school accountability in urban Title I schools

This study examined the effects of student mobility and educational enrollment experiences on academic achievement. The educational progress, school enrollments and transfers of inner-city elementary students were tracked over a four-year period. Student achievement was measured by criterion-referenced reading tests administered in the second semester of the third grade. It further analyzed the degree to which the switch to different basal reading textbooks interrupted the continuity of education thereby contributing to the detrimental effects of intra-district mobility. ^ Mobility histories of 2,913 third grade students were collected to evaluate the number of times each student entered or withdrew from a Miami-Dade County Public School beginning in August 2000 through March 2004, and distinguished between transfers that occurred during the academic school year and those that occurred during summer months. Data were analyzed using Pearson correlations and multiple regressions to determine if school mobility contributed to performance on the Florida Comprehensive Assessment Third Grade Reading Test (FCAT). Transferring from one school to another was found to have a significant negative impact on student test scores. Transfers within the academic school year were more detrimental than transfers that occurred during the summer months. Third grade students who transferred into schools that used the same reading textbook series were found to have significantly higher FCAT reading scores than third graders who transferred into schools that used different reading textbooks. ^ The effects of mobility rates on overall school performance were also examined. Data was collected on 124 Title I elementary schools to determine the degree to which mobility affected school accountability scores. Title I schools with high student mobility rates had significantly lower accountability scores than schools with lower student mobility rates. ^ The results of this study highlight the impact of education and housing policy and imply a need for programs and practices that promote stability in the early elementary years. ^

Specific binding of the mammalian high mobility group protein AT-hook 2 to the minor groove of AT -rich DNAs: Thermodynamic and specificity studies

The mammalian high mobility group protein AT-hook 2 (HMGA2) is a small transcriptional factor involved in cell development and oncogenesis. It contains three "AT-hook" DNA binding domains, which specifically recognize the minor groove of AT-rich DNA sequences. It also has an acidic C-terminal motif. Previous studies showed that HMGA2 mediates all its biological effects through interactions with AT-rich DNA sequences in the promoter regions. In this dissertation, I used a variety of biochemical and biophysical methods to examine the physical properties of HMGA2 and to further investigate HMGA2's interactions with AT-rich DNA sequences. The following are three avenues perused in this study: (1) due to the asymmetrical charge distribution of HMGA2, I have developed a rapid procedure to purify HMGA2 in the milligram range. Preparation of large amounts of HMGA2 makes biophysical studies possible; (2) Since HMGA2 binds to different AT-rich sequences in the promoter regions, I used a combination of isothermal titration calorimetry (ITC) and DNA UV melting experiment to characterize interactions of HMGA2 with poly(dA-dT) 2 and poly(dA)poly(dT). My results demonstrated that (i) each HMGA2 molecule binds to 15 AT bp; (ii) HMGA2 binds to both AT DNAs with very high affinity. However, the binding reaction of HMGA2 to poly(dA-dT) 2 is enthalpy-driven and the binding reaction of HMGA2 with poly(dA)poly(dT) is entropy-driven; (iii) the binding reactions are strongly depended on salt concentrations; (3) Previous studies showed that HMGA2 may have sequence specificity. In this study, I used a PCR-based SELEX procedure to examine the DNA binding specificity of HMGA2. Two consensus sequences for HMGA2 have been identified: 5'-ATATTCGCGAWWATT-3' and 5'-ATATTGCGCAWWATT-3', where W represents A or T. These consensus sequences have a unique feature: the first five base pairs are AT-rich, the middle four to five base pairs are GC-rich, and the last five to six base pairs are AT-rich. All three segments are critical for high affinity binding. Replacing either one of the AT-rich sequences to a non-AT-rich sequence causes at least 100-fold decrease in the binding affinity. Intriguingly, if the GC-segment is substituted by an AT-rich segment, the binding affinity of HMGA2 is reduced approximately 5-fold. Identification of the consensus sequences for HMGA2 represents an important step towards finding its binding sites within the genome.

The utilization of chiral ion mobility spectrometry for the detection of enantiomeric mixtures and thermally labile compounds

This dissertation utilized electrospray ion mobility mass spectrometry (ESI-IMS-MS) to develop methods necessary for the separation of chiral compounds of forensic interest. The compounds separated included ephedrines and pseudoephedrines, that occur as impurities in confiscated amphetamine type substances (ATS) in an effort to determine the origin of these substances. The ESI-IMS-MS technique proved to be faster and more cost effective than traditional chromatographic methods currently used to conduct chiral separations such as gas and liquid chromatography. Both mass spectrometric and computational analysis revealed the separation mechanism of these chiral interactions allowing for further development to separate other chiral compounds by IMS. Successful separation of chiral compounds was achieved utilizing a variety of modifiers injected into the IMS drift tube. It was found that the modifiers themselves did not need to be chiral in nature and that achiral modifiers were sufficient in performing the required separations. The ESI-IMS-MS technique was also used to detect thermally labile compounds which are commonly found in explosive substances. The methods developed provided mass spectrometric identification of the type of ionic species being detected from explosive analytes as well as the appropriate solvent that enhances detection of these analytes in either the negative or positive ion mode. An application of the developed technique was applied to the analysis of a variety of low explosive smokeless powder samples. It was found that the developed ESI-IMS-MS technique not only detected the components of the smokeless powders, but also provided data that allowed the classification of the analyzed smokeless powders by manufacturer or make. ^

The Construction and Optimization on an Ion Mobility Spectrometer for the Analysis of Explosives and Drugs

Today, over 15,000 Ion Mobility Spectrometry (IMS) analyzers are employed at worldwide security checkpoints to detect explosives and illicit drugs. Current portal IMS instruments and other electronic nose technologies detect explosives and drugs by analyzing samples containing the headspace air and loose particles residing on a surface. Canines can outperform these systems at sampling and detecting the low vapor pressure explosives and drugs, such as RDX, PETN, cocaine, and MDMA, because these biological detectors target the volatile signature compounds available in the headspace rather than the non-volatile parent compounds of explosives and drugs. In this dissertation research volatile signature compounds available in the headspace over explosive and drug samples were detected using SPME as a headspace sampling tool coupled to an IMS analyzer. A Genetic Algorithm (GA) technique was developed to optimize the operating conditions of a commercial IMS (GE Itemizer 2), leading to the successful detection of plastic explosives (Detasheet, Semtex H, and C-4) and illicit drugs (cocaine, MDMA, and marijuana). Short sampling times (between 10 sec to 5 min) were adequate to extract and preconcentrate sufficient analytes (> 20 ng) representing the volatile signatures in the headspace of a 15 mL glass vial or a quart-sized can containing ≤ 1 g of the bulk explosive or drug. Furthermore, a research grade IMS with flexibility for changing operating conditions and physical configurations was designed and fabricated to accommodate future research into different analytes or physical configurations. The design and construction of the FIU-IMS were facilitated by computer modeling and simulation of ion’s behavior within an IMS. The simulation method developed uses SIMION/SDS and was evaluated with experimental data collected using a commercial IMS (PCP Phemto Chem 110). The FIU-IMS instrument has comparable performance to the GE Itemizer 2 (average resolving power of 14, resolution of 3 between two drugs and two explosives, and LODs range from 0.7 to 9 ng). The results from this dissertation further advance the concept of targeting volatile components to presumptively detect the presence of concealed bulk explosives and drugs by SPME-IMS, and the new FIU-IMS provides a flexible platform for future IMS research projects.

Headspace Analysis of Smokeless Powders: Development of Mass Calibration Methods using Microdrop Printing for Chromatographic and Ion Mobility Spectrometric Detection

Smokeless powder additives are usually detected by their extraction from post-blast residues or unburned powder particles followed by analysis using chromatographic techniques. This work presents the first comprehensive study of the detection of the volatile and semi-volatile additives of smokeless powders using solid phase microextraction (SPME) as a sampling and pre-concentration technique. Seventy smokeless powders were studied using laboratory based chromatography techniques and a field deployable ion mobility spectrometer (IMS). The detection of diphenylamine, ethyl and methyl centralite, 2,4-dinitrotoluene, diethyl and dibutyl phthalate by IMS to associate the presence of these compounds to smokeless powders is also reported for the first time. A previously reported SPME-IMS analytical approach facilitates rapid sub-nanogram detection of the vapor phase components of smokeless powders. A mass calibration procedure for the analytical techniques used in this study was developed. Precise and accurate mass delivery of analytes in picoliter volumes was achieved using a drop-on-demand inkjet printing method. Absolute mass detection limits determined using this method for the various analytes of interest ranged between 0.03 - 0.8 ng for the GC-MS and between 0.03 - 2 ng for the IMS. Mass response graphs generated for different detection techniques help in the determination of mass extracted from the headspace of each smokeless powder. The analyte mass present in the vapor phase was sufficient for a SPME fiber to extract most analytes at amounts above the detection limits of both chromatographic techniques and the ion mobility spectrometer. Analysis of the large number of smokeless powders revealed that diphenylamine was present in the headspace of 96% of the powders. Ethyl centralite was detected in 47% of the powders and 8% of the powders had methyl centralite available for detection from the headspace sampling of the powders by SPME. Nitroglycerin was the dominant peak present in the headspace of the double-based powders. 2,4-dinitrotoluene which is another important headspace component was detected in 44% of the powders. The powders therefore have more than one headspace component and the detection of a combination of these compounds is achievable by SPME-IMS leading to an association to the presence of smokeless powders.

Internet Protocol (IP) design and implementation for efficient mobility to devices in wireless networks

The purpose of this thesis was to develop an efficient routing protocol which would provide mobility support to the mobile devices roaming within a network. The routing protocol need to be compatible with the existing internet architecture. The routing protocol proposed here is based on the Mobile IP routing protocol and could solve some of the problems existing in current Mobile IP implementation e.g. ingress filtering problem. By implementing an efficient timeout mechanism and introducing Paging mechanism to the wireless network, the protocol minimizes the number of control messages sent over the network. The implementation of the system is primarily done on three components: 1) Mobile devices that need to gain access to the network, 2) Router which would be providing roaming support to the mobile devices and 3) Database server providing basic authentication services on the system. As a result, an efficient IP routing protocol is developed which would provide seamless mobility to the mobile devices on the network.

Tradução, adaptação cultural e propriedades psicométricas da versão brasileira do mobility assessment tool physical activity (MAT-PA) em idosos comunitários brasileiros

Objetivo: Traduzir e avaliar as propriedades psicométricas do Mobility Assessment Tool Physical Activity (MAT-PA) em idosos comunitários brasileiros. Métodos: Trata-se de um estudo tradução, adaptação cultural, e acurácia do instrumento MAT-PA, no qual foram avaliados 329 idosos, com idade mínima de 60 anos, residentes na comunidade. Os indivíduos submeteram-se a um formulário de avaliação composto por: questionário sócio-demográfico e de saúde percebida; avaliação física; Prova Cognitiva de Leganés (PCL); Center for Epidemiologic Studies Depression Scale (CES-D); International Physical Activity Questionnaire (IPAQ); Mobility Assessment Tool Physical Activity (MAT-PA). Dessa amostra total, 42 idosos utilizaram o acelerômetro durante 8 dias. Para verificar a confiabilidade teste-reteste do MAT-PA, reaplicou-se esse instrumento em 34 idosos 8 dias após a primeira avaliação. A análise estatística utilizada foi a correlação de Spearman, o Coeficiente de Correlação Intra-classe, o coeficiente α de Cronbach, o Bland-Altman e o teste T pareado. Resultados: As correlações dos dados IPAQ e acelerômetro versus o escore total do MAT-PA foram significativas e apresentaram um coeficiente de correlação de Spearman de 0,13 e 0,41, respectivamente. Analisou-se também a confiabilidade que apresentou as seguintes medidas: consistência interna, pelo coeficiente alfa de Cronbach (α= 0,70); Concordância teste-reteste, pelo coeficiente de correlação intra-classe (CCI=0,53; p<0,001). Conclusão: A versão brasileira do Mobility Assessment Tool Physical Activity (MAT-PA) como um instrumento de avaliação da atividade física de idosos, mostrou ser um método válido e confiável.

Desempenho físico em idosos com diferenciados perfis epidemiológicos: análise do estudo IMIAS International Mobility in Aging Study sob a perspectiva do curso da vida e de biomarcadores da inflamação e do estresse

O crescimento demográfico de idosos é um fenômeno mundial e exerce influência sobre o desenvolvimento e funcionamento das sociedades. Fatores sociais, econômicos, ambientais, biológicos e culturais influenciam o processo de envelhecimento, que pode vir acompanhado de contínua perda na capacidade de adaptação do indivíduo ao meio ambiente, de maior vulnerabilidade ao estresse, limitações funcionais e diminuição da qualidade de vida do indivíduo. Todavia, ao longo do curso da vida, o indivíduo vivencia múltiplas exposições adversas à saúde, e o declínio da mobilidade surge como um dos primeiros sinais do envelhecimento, repercutindo na saúde física e mental do indivíduo. Para contribuir com o conhecimento sobre os desfechos relacionados ao envelhecimento e mobilidade, o estudo IMIAS investiga idosos em quatro países com diferentes perfis epidemiológicos. O presente estudo abordou os possíveis fatores associados ao declínio físico em idosos de distintas sociedades, sobre a perspectiva epidemiológica do curso da vida e dos biomarcadores da inflamação e do estresse. Objetivos: 1) Analisar as relações entre as adversidades sociais e econômicas, vivenciadas durante a infância, a fase adulta e a velhice, com o baixo desempenho físico em populações idosas, de diferentes contextos sociais, econômicos e culturais. 2) Verificar a associação entre os níveis elevados da proteína c-reativa (PCR) com o desempenho físico em idosos de diferentes populações. 3) Avaliar se a desregulação nos níveis de cortisol diurno exerce influência sobre o desempenho físico em idosos com distintos perfis epidemiológicos. Métodos: Foram utilizados dados da linha de base do IMIAS – Estudo Internacional de Mobilidade no Envelhecimento, composto por 1.995 indivíduos entre 65 e 74 anos de idade, residentes em comunidades de quatro países (Albânia, Brasil, Canadá, Colômbia). O desempenho físico foi avaliado através do Short Physical Performance Battery (SPPB) e da força de preensão manual. As adversidades durante o curso da vida foram estimadas a partir de eventos e exposições sociais, econômicas e culturais ocorridas durante a infância, fase adulta e velhice. Para avaliar o percurso biológico e suas associações com a mobilidade, a proteína c-reativa e o cortisol foram considerados como biomarcadores da inflamação e do estresse, respectivamente. No sentido de responder as questões de investigações, foram conduzidas análises de estatística descritiva, bivariada e multivariada, mediante técnicas de distribuição de frequências, teste qui-quadrado, odds ratio e regressões logística, linear e multinível. Resultados: O desempenho físico foi menor nos participantes que vivem na Colômbia, Brasil e Albânia do que nos que vivem no Canadá, mesmo quando ajustados por idade, sexo e adversidades durante o curso da vida. O baixo nível de desempenho físico (SPPB < 8) foi associado a ter sofrido adversidade social e econômica na infância, ter tido ocupação semiqualificada na fase adulta, morar sozinho e possuir renda insuficiente na velhice. A PCR esteve associada com a baixa força de preensão manual e com o SPPB<8. Entretanto, a associação entre a PCR e a força de preensão manual não se manteve quando ajustada por fatores socioeconômicos e hábitos de saúde. As associações negativas entre SPPB e PCR permaneceram significativas mesmo após ajustes por idade, sexo, escolaridade, local de pesquisa e condições de saúde. O baixo desempenho físico (SPPB ≤ 8) foi associado com uma significativa diminuição nos níveis de cortisol ao acordar, em comparação com os níveis de cortisol de idosos com bom desempenho físico (SPPB > 8), mesmo após modelos controlados por local de estudo, sexo, depressão, hábitos de saúde, uso de psicotrópicos e índice de massa corporal. Conclusões: Os resultados evidenciaram associação entre a inflamação, o estresse e as desigualdades sociais e econômicas na infância, sobre o desempenho físico de idosos com diferenciados perfis epidemiológicos. Enfatizamos que a promoção do envelhecimento saudável requer considerar políticas e práticas que favoreçam o bem-estar econômico e social para crianças, adultos e idosos.

Prevalência, fatores associados e efeitos da violência doméstica na mobilidade em idosos: evidências do estudo imias (international mobility in aging study) sob a perspectiva epidemiológica do curso da vida

A capacidade de mover-se com independência e segurança é fundamental para a execução das atividades de vida diária e manutenção da qualidade de vida do indivíduo. Diversos fatores, dentre eles o envelhecimento podem contribuir para seu declínio. Estudos têm demonstrado associação entre experiências de violência doméstica (VD) e diversos problemas de saúde física e mental. Até o momento, não há estudos que tenham avaliado a associação entre experiências de VD no curso de vida e limitações de mobilidade na senescência. OBJETIVOS: estimar a prevalência da VD (física e psicológica) em idosos, e avaliar o impacto da VD no curso de vida na limitação de mobilidade. MATERIAIS E MÉTODO: Estudo observacional analítico a partir da primeira coleta de dados do estudo longitudinal International Mobility in Aging Study (IMIAS). Idosos (n = 1995) de ambos os sexos entre 65 e 74 anos de cinco localidades distintas (Kingston e Saint-Hyacinthe, Canadá; Tirana, Albânia; Maniazales, Colômbia; e Natal, Brasil) participaram do estudo. Dados sobre variáveis sociodemográficas, econômicas, condições de saúde e experiências de VD (física e psicológica) durante o curso de vida foram coletados. A limitação de mobilidade na senescência foi avaliada pelo Short Physical Performance Battery (SPPB) e pela dificuldade de andar 400 metros e/ou subir um lance de escadas. As prevalências foram avaliadas mediante frequências absolutas e relativas das exposições à VD, limitação de mobilidade e co-variáveis. Diferenças de gênero, bem como entre cidades foram analisadas utilizando o teste de qui-quadrado. Associação entre exposição à VD e limitação de mobilidade foi avaliada utilizando a regressão logística binária multivariada, ajustando pelas co-variáveis. Análise de mediação foram utilizadas, para avaliar possíveis caminhos entre a exposição à VD no curso de vida e a limitação de mobilidade. RESULTADOS: A violência física foi rara, com valores entre 0,63 e 0,85%. Relatos de violência psicológica variaram entre 3,2% e 23,5% (homens) e de 9% para 26% (mulheres). Mulheres experimentaram mais violência do que os homens em Saint-Hyacinthe (homens: 3,2% vs mulheres: 14%, p <0,001), Tirana (homens: 4,3% vs mulheres: 10,3%, p = 0,017), em Manizales (homens: 8,3 % vs mulheres: 18,3%, p = 0,004) e Natal (homens: 11,1% vs mulheres: 26%, p = 0,002). Em geral, o baixo suporte social pelo parceiro foi associado com a VD. Estar trabalhando foi associado a vitimização entre os homens, enquanto o oposto foi verdade para as mulheres. Arranjos de vida Multi-familiares e baixo suporte pelos parceiros, filhos e família foram associados com a VD. Baixo suporte social foi da maior importância para as mulheres do que os homens. A VD física foi associada tanto com o SPPB < 8 (OR 1,623 95%IC 1,161-2,269) como com a dificuldade para andar 400 metros e/ou subir um lance de escadas (OR 1,394 95%IC 1,063-1,829). A limitação de mobilidade decorrente da violência física no curso de vida pelo parceiro íntimo foi mediada pelas condições crônicas (efeito 25,56% 95%IC 0,036-0,277) e depressão (efeito 33,05% 95%IC 0,087-0,333). No caso da violência física por outros familiares, a limitação de mobilidade foi mediada pelas condições crônicas (efeito 20,85% 95%IC 0,022-0,202), não adesão à prática de atividades físicas (efeito 34,14% 95%IC 0,076-0,351) e depressão (efeito 44,40% 95%IC 0,144-0,315). CONCLUSÕES: A violência doméstica no curso de vida é uma realidade, que pode acarretar consequências que favorecem a limitação de mobilidade em idosos. São necessárias políticas públicas que combatam efetivamente a violência doméstica, garantindo um envelhecimento mais digno e independente funcionalmente.

Households without Houses : Mobility and Moorings on the Eurasian Steppe

Peer reviewed

Key figure of mobility : The pedestrian

Peer reviewed

The geological and microbiological controls on the occurrence, mobility and concentration of Se and Te in coal and black shales

© 2016 Institute of Materials, Minerals and Mining and The AusIMM Published by Taylor & Francis on behalf of the Institute and The AusIMM

Mobility and toxicity of heavy metal(loid)s arising from contaminated wood ash application to a pasture grassland soil

The authors acknowledge the financial support the Scottish Government’s Rural and Environmental Sciences and Analytical Services (RESAS) in order to complete some of the soil and pore water sample analysis as well as the Czech Ministry of Education, Youth and Sports (COST CZ LD13068), the Czech Science Foundation (GAČR 14-02183P) and EU COST actionFP1407 (‘ModWoodLife’) short term scientific mission grant in order to complete the column leaching test.

On the mobility, membrane location and functionality of mechanosensitive channels in Escherichia coli

We thank Frans Bianchi and Franz Ho for assistance with molecular cloning, Tim Rasmussen for providing the pTRC-MscK plasmid, Andrew Robinson for providing the pBAD-mEos3.2 plasmid, Matthias Heinemann for assistance with the flow cytometry measurements, Paul Schavemaker for performing Smoldyn simulations and Michiel Punter for programming ImageJ plugins for PALM reconstructions and single-particle tracking. We thank Ian Booth for critical reading of the manuscript, and Christoffer Åberg and Matteo Gabba for valuable discussions. The authors would like to thank David Dryden and Marcel Reuter for performing preliminary experiments from which this work has been built. The work was funded by the EU FP7 ITN-network program NICHE.