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1.
Appl Ergon ; 116: 104206, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38141524

RESUMO

Trams are experiencing a resurgence with worldwide network expansion driven by the need for sustainable and efficient cities. Trams often operate in shared or mixed-traffic environments, which raise safety concerns, particularly in hazardous situations. This paper adopts an international, mixed-methods approach, conducted through two interconnected studies in Melbourne (Australia) and Birmingham (UK). The first study involved qualitative interviews, while the second was an experimental study involving a virtual reality (VR) simulator and haptic master controller (i.e., speed lever). In tram operations, master controllers play a critical role in ensuring a smooth ride, which directly influences passenger safety and comfort. The objective was to understand how a master control system, enhanced with additional haptic feedback, could improve tram driver braking performance and perceptions in safety-critical scenarios. Interview results indicate that the use of the emergency brake is considered the final or ultimate choice by drivers, and their driving experience is a moderating factor in limiting its application. Combined with the experimental results, this paper highlights how implementing haptic feedback within a master controller can reduce the performance disparity between novice and experienced tram drivers.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Humanos , Retroalimentação , Tecnologia Háptica , Veículos Automotores
2.
eNeuro ; 9(5)2022.
Artigo em Inglês | MEDLINE | ID: mdl-36028331

RESUMO

There is currently no robust method to evaluate how built environment design affects our emotion. Understanding emotion is significant, as it influences cognitive processes, behavior, and wellbeing, and is linked to the functioning of physiological systems. As mental health problems are becoming more prevalent, and exposure to indoor environments is increasing, it is important we develop rigorous methods to understand whether design elements in our environment affect emotion. This study examines whether the scale of interior built environments modulate neural networks involved in emotion regulation. Using a Cave Automatic Virtual Environment (CAVE) and controlling for indoor environmental quality (IEQ), 66 adults (31 female, aged 18-55) were exposed to context-neutral enclosed indoor room scenes to understand whether built environment scale affected self-report, autonomic nervous system, and central nervous system correlates of emotion. Our results revealed enlarged scale increased electroencephalography (EEG) power in the ß bandwidth. Frontal midline low-γ and high-γ power were also found to increase with enlarged scale, but contrary to our hypothesis, scale did not modulate frontal midline power or lateralization in the θ or α bandwidths. We did not detect an effect of scale on autonomic indicators or self-reported emotion. However, we did find increased range in skin conductance response (SCR) and heart rate variability (HRV) to the built environment conditions. This study provides a rigorous empirical framework for assessing the environmental impact of a design characteristic on human emotion and suggests that measures of high-frequency oscillations may provide a useful marker of the response to built environment.


Assuntos
Sistema Nervoso Autônomo , Eletroencefalografia , Adulto , Ambiente Construído , Emoções/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos
3.
Psychophysiology ; 59(12): e14121, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35723272

RESUMO

Understanding built environment exposure as a component of environmental enrichment has significant implications for mental health, but little is known about the effects design characteristics have on our emotions and associated neurophysiology. Using a Cave Automatic Virtual Environment while monitoring indoor environmental quality (IEQ), 18 participants were exposed to a resting state (black), and two room scenes, control (white) and condition (blue), to understand if the color of the virtual walls affected self-report, autonomic nervous system, and central nervous system correlates of emotion. Our findings showed that exposure to the chromatic color condition (blue) compared to the achromatic control (white) and resting-state (black, no built environment) significantly increased the range in respiration and skin conductance response. We also detected a significant increase in alpha frontal midline power and frontal hemispheric lateralization relative to blue condition, and increased power spectral density across all electrodes in the blue condition for theta, alpha, and beta bandwidths. The ability for built environment design to modulate emotional response has the potential to deliver significant public health, economic, and social benefits to the entire community. The findings show that blue coloring of the built environment increases autonomic range and is associated with modulations of brain activity linked to emotional processing.


Assuntos
Sistema Nervoso Autônomo , Eletroencefalografia , Humanos , Sistema Nervoso Autônomo/fisiologia , Emoções/fisiologia , Sistema Nervoso Central
4.
Ergonomics ; 65(3): 445-466, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34487483

RESUMO

Tram drivers operate a master controller to control the acceleration and braking of the tram. Operation should ensure passenger comfort and safety through smooth tram motion and the avoidance of jerkiness that may cause passengers to fall in the carriage. This work investigates current driver practices and strategies for tram driving in normal operations through interviews and the capacity of a new haptic master controller to support drivers in achieving smooth and safe tram journeys. A haptic feedback algorithm based on viscosity was implemented on the master controller to provide drivers with feedback on the rate at which they were accelerating and braking the tram. This aspect was tested in a virtual tram within a simulated inner city virtual reality environment. Results indicate that the haptic master controller and coupled viscosity feedback algorithm did not increase smoothness of driving during the simulated experiences. Despite this, the drivers indicated a preference for the provision of further haptic information to support driving tasks and the overall journey safety and smoothness. Practitioner Summary: This research comprises two studies. The first investigates strategies currently used by drivers to operate a tram smoothly in order to elicit design requirements for a haptic tram master controller. The second study evaluates the impact of a novel haptic master controller on journey smoothness within a virtual environment.


Assuntos
Condução de Veículo , Realidade Virtual , Retroalimentação , Tecnologia Háptica , Humanos , Veículos Automotores , Interface Usuário-Computador
5.
Inorg Chem ; 57(16): 10331-10340, 2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-30058805

RESUMO

The paddlewheel complex Ru2(chp)4Cl (1-Cl, chp = 6-chloro-2-oxypyridinate), upon reduction with Zn, has been previously shown to dimerize to [Ru2(chp)4]2 (2), blocking further chemistry at the Ru2(II,II) axial site [ Inorg. Chem. 2015 , 54 , 8571 - 8589 ]. Functionalization of the chp ligand at the 3 and 5 positions with either bromine (dbchpH = 3,5-dibromo-6-chloro-2-pyridone) or trimethylsilyl (TMS) groups (dsichpH = 6-chloro-3,5-bis(trimethylsilyl)-2-pyridone) allows for the preparation of the Ru2(II,II) paddlewheel complexes Ru2(dbchp)4 (3) and Ru2(dsichp)4 (6), respectively, neither of which shows evidence of dimerization. Though the utilization of 3 is limited due to insolubility, complex 6 is soluble even in typically non-coordinating solvents, forming a stable κ1-axial adduct in CH2Cl2 (6-CH2Cl2) and showing evidence of an axial interaction with n-decane. The first example of an axially free Ru2(II,II) complex with a 3A ground state is observed upon crystallization of 6 from benzene (6-C6D6). Complex 6 is accessed via Zn reduction of Ru2(dsichp)4Cl (4-Cl), which along with Ru2(dsichp)4N3 (4-N3), show similar structural and electronic properties to their non-TMS-substituted analogues, 1-Cl and 1-N3. Photolysis of 4-N3 in frozen solution generates Ru2(dsichp)4N (5); no N atom transfer to PPh3 is observed upon room temperature photolysis in fluid solution.

6.
Sensors (Basel) ; 17(3)2017 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-28335431

RESUMO

The Robot Operating System (ROS) provides roboticists with a standardized and distributed framework for real-time communication between robotic systems using a microkernel environment. This paper looks at how ROS metadata, Unified Robot Description Format (URDF), Semantic Robot Description Format (SRDF), and its message description language, can be used to identify key robot characteristics to inform User Interface (UI) design for the teleoperation of heterogeneous robot teams. Logical relationships between UI components and robot characteristics are defined by a set of relationship rules created using relevant and available information including developer expertise and ROS metadata. This provides a significant opportunity to move towards a rule-driven approach for generating the designs of teleoperation UIs; in particular the reduction of the number of different UI configurations required to teleoperate each individual robot within a heterogeneous robot team. This approach is based on using an underlying rule set identifying robots that can be teleoperated using the same UI configuration due to having the same or similar robot characteristics. Aside from reducing the number of different UI configurations an operator needs to be familiar with, this approach also supports consistency in UI configurations when a teleoperator is periodically switching between different robots. To achieve this aim, a Matlab toolbox is developed providing users with the ability to define rules specifying the relationship between robot characteristics and UI components. Once rules are defined, selections that best describe the characteristics of the robot type within a particular heterogeneous robot team can be made. A main advantage of this approach is that rather than specifying discrete robots comprising the team, the user can specify characteristics of the team more generally allowing the system to deal with slight variations that may occur in the future. In fact, by using the defined relationship rules and characteristic selections, the toolbox can automatically identify a reduced set of UI configurations required to control possible robot team configurations, as opposed to the traditional ad-hoc approach to teleoperation UI design. In the results section, three test cases are presented to demonstrate how the selection of different robot characteristics builds a number of robot characteristic combinations, and how the relationship rules are used to determine a reduced set of required UI configurations needed to control each individual robot in the robot team.

7.
Appl Environ Microbiol ; 79(6): 2081-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23335760

RESUMO

Resources from the Sinorhizobium meliloti Rm1021 open reading frame (ORF) plasmid libraries were used in a medium-throughput method to construct a set of 50 overlapping deletion mutants covering all of the Rm1021 pSymA megaplasmid except the replicon region. Each resulting pSymA derivative carried a defined deletion of approximately 25 ORFs. Various phenotypes, including cytochrome c respiration activity, the ability of the mutants to grow on various carbon and nitrogen sources, and the symbiotic effectiveness of the mutants with alfalfa, were analyzed. This approach allowed us to systematically evaluate the potential impact of regions of Rm1021 pSymA for their free-living and symbiotic phenotypes.


Assuntos
DNA Bacteriano/genética , Biblioteca Gênica , Plasmídeos , Deleção de Sequência , Sinorhizobium meliloti/genética , Carbono/metabolismo , Medicago sativa/microbiologia , Nitrogênio/metabolismo , Fases de Leitura Aberta , Sinorhizobium meliloti/crescimento & desenvolvimento , Sinorhizobium meliloti/metabolismo , Sinorhizobium meliloti/fisiologia , Simbiose
8.
Environ Manage ; 48(3): 644-57, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21739344

RESUMO

U.S. Forest Service managers are required to incorporate social and biophysical science information in planning and environmental analysis. The use of science is mandated by the National Environmental Policy Act, the National Forest Management Act, and U.S. Forest Service planning rules. Despite the agency's emphasis on 'science-based' decision-making, little is known about how science is actually used in recreation planning and management. This study investigated the perceptions of Forest Service interdisciplinary (ID) team leaders for 106 NEPA projects dealing with recreation and travel management between 2005 and 2008. Our survey data show how managers rate the importance of social and biophysical science compared to other potential 'success factors' in NEPA assessments. We also explore how team leaders value and use multi-disciplinary tools for recreation-related assessments. Results suggest that managers employ a variety of recreation planning tools in NEPA projects, but there appears to be no common understanding or approach for how or when these tools are incorporated. The Recreation Opportunity Spectrum (ROS) was the most frequently used planning tool, but the Visitor Experience and Resource Protection (VERP) framework was the most consistently valued tool by those who used it. We recommend further evaluation of the strengths and weaknesses of each planning tool and future development of procedures to select appropriate planning tools for use in recreation-related NEPA assessments.


Assuntos
Conservação dos Recursos Naturais/métodos , Agricultura Florestal/métodos , Recreação , Árvores/fisiologia , Tomada de Decisões Gerenciais , Política Ambiental , Humanos , Medição de Risco/métodos , Gestão de Riscos/métodos , Viagem , Árvores/crescimento & desenvolvimento , Estados Unidos , United States Environmental Protection Agency
9.
Dalton Trans ; 39(21): 5101-7, 2010 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-20411190

RESUMO

Aluminosilicates with varying Al2O3:SiO2 molar ratios (3:1, 3:2, 3:3 and 3:4) have been synthesized using a hybrid sol-gel route using boehmite sol as the precursor for alumina and tetraethyl orthosilicate (TEOS) as the precursor for silica. The synthesis of boehmite sol from aluminium nitrate, and its use as the alumina precursor, is cost effective compared to alkoxide precursors. Structural aspects, including bonding and coordination, are studied in detail for samples calcined in the temperature range 400-1400 °C using both NMR and FTIR spectroscopy: the results are correlated with phase formation data (spinel and high temperature phases) obtained from XRD and thermal analysis. FTIR results show a broadening of peaks at 800 °C indicating a disordered distribution of octahedral sites caused by crosslinking between AlO6 octahedral and SiO4 tetrahedral units prior to the formation of mullite. (27)Al MAS NMR spectra are consistent with a progressive decrease in the number of AlO6 polyhedra with increasing temperature corresponding to Al in these units being forced to adopt a tetrahedral coordination due to the increasing presence of similarly coordinated Si species. XRD results confirm the formation of pure mullite at 1250 °C for a 3Al2O3:2SiO2 system. At 1400 °C, phase pure mullite is observed for all compositions except 3Al2O3:SiO2 where α-Al2O3 is the major phase with traces of mullite. The synthesis of aluminosilicates through a hybrid sol-gel route and the detailed insight into structural features gained from spectroscopic and diffraction techniques contributes further to the development of these materials in applications ranging from nanocatalysts to high-temperature ceramics.

10.
J Environ Manage ; 91(6): 1371-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20223581

RESUMO

We conducted a survey of 3321 Forest Service employees involved in compliance with the National Environmental Policy Act (NEPA) followed by five focus groups to investigate agency views of the purpose of agency NEPA processes and their appropriate measures of success. Results suggest the lack of a unified critical task for Forest Service NEPA processes and that employees' functions relevant to NEPA influence their views of its meaning. Compared to other agency personnel, members of interdisciplinary teams who carry out most day-to-day NEPA-related tasks placed greater emphasis on minimizing negative environmental and social impacts, satisfying multiple stakeholders and avoiding litigation and appeals. Line officers, who typically serve as the decision makers following NEPA processes, placed greatest emphasis on efficient implementation and least emphasis on minimizing impacts. Advisory personnel placed greatest emphasis on effective disclosure of analyses and decision-making. We discuss the structural origins of these differences as well as their implications.


Assuntos
Meio Ambiente , Agricultura Florestal , Tomada de Decisões Gerenciais , Estados Unidos
11.
J Environ Manage ; 91(6): 1350-6, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20223584

RESUMO

We conducted an online survey (n = 3321) followed by five focus groups with Forest Service employees involved in compliance with the National Environmental Policy Act (NEPA) to explore agency views of how NEPA should be implemented within the agency. We filter these perceptions through the lenses of different functional groups within the agency, each with its own role in agency compliance with NEPA and its own suite of perceived accountabilities. In doing so, we uncover areas of consensus regarding valued practices as well as tensions between employees with different roles in NEPA compliance. General consensus exists regarding the importance of the effective functioning of interdisciplinary teams, but opinions about what constitutes an effective team vary. Findings suggest that NEPA serves as a playing field for competing accountabilities felt by line officers, disciplinary specialists, and advisory personnel within the agency, as each attempts to exert influence over NEPA processes and their outcomes.


Assuntos
Meio Ambiente , Árvores , Estados Unidos
12.
Appl Environ Microbiol ; 74(21): 6756-65, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18791020

RESUMO

The Sinorhizobium meliloti ORFeome project cloned 6,314 open reading frames (ORFs) into a modified Gateway entry vector system from which the ORFs could be transferred to destination vectors in vivo via bacterial conjugation. In this work, a reporter gene destination vector, pMK2030, was constructed and used to generate ORF-specific transcriptional fusions to beta-glucuronidase (gusA) and green fluorescent protein (gfp) reporter genes. A total of 6,290 ORFs were successfully transferred from the entry vector library into pMK2030. To demonstrate the utility of this system, reporter plasmids corresponding to 30 annotated sugar kinase genes were integrated into the S. meliloti SM1021 and/or SM8530 genome. Expression of these genes was measured using a high-throughput beta-glucuronidase assay to track expression on nine different carbon sources. Six ORFs integrated into SM1021 and SM8530 had different basal levels of expression in the two strains. The annotated activities of three other sugar kinases were also confirmed.


Assuntos
Fusão Gênica Artificial , Proteínas de Bactérias/metabolismo , Glucuronidase/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Sinorhizobium meliloti/genética , Sinorhizobium meliloti/metabolismo , Coloração e Rotulagem/métodos , Proteínas de Bactérias/genética , DNA Bacteriano , Perfilação da Expressão Gênica , Genes Reporter , Vetores Genéticos , Glucuronidase/genética , Proteínas de Fluorescência Verde/genética , Dados de Sequência Molecular , Plasmídeos , Proteínas Recombinantes de Fusão/genética , Recombinação Genética , Análise de Sequência de DNA
13.
Environ Manage ; 41(5): 640-53, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18299917

RESUMO

Political and legal conflicts between the need for targeted private forest conservation and the continued assurance of private property rights in the U.S. presents a seemingly intractable resource management problem. Scandinavian use of habitat protection areas on private forests offers an additional tool that may be suitable for solving the historical and on-going tension found within U.S. efforts to reconcile desires to maintain lands in a forested condition while also respecting private property rights. This article presents a comparative cross-sectional policy analysis of Sweden, Finland, and the U.S., supported with a supplemental case example from the Commonwealth of Virginia. Similarities in all three countries among forest ownership patterns, use of public subsidies, and changing attitudes towards conservation are generally encouraging. Additionally, Virginia's current consideration and development of state-wide forest policies focused on forestland and open space conservation suggests both a need and an opportunity to systematically assess the applicability of the Nordic forest reserve approach to local private forest conservation. Future research at a high-resolution, and specifically at the state level, should focus on the social and political factors that would ultimately determine the viability of a forest reserve program.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Propriedade/legislação & jurisprudência , Constituição e Estatutos , Ecossistema , Finlândia , Agricultura Florestal/legislação & jurisprudência , Humanos , Formulação de Políticas , Valores Sociais , Suécia , Virginia
14.
Appl Environ Microbiol ; 71(10): 5858-64, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16204497

RESUMO

The nitrogen-fixing, symbiotic bacterium Sinorhizobium meliloti reduces molecular dinitrogen to ammonia in a specific symbiotic context, supporting the nitrogen requirements of various forage legumes, including alfalfa. Determining the DNA sequence of the S. meliloti genome was an important step in plant-microbe interaction research, adding to the considerable information already available about this bacterium by suggesting possible functions for many of the >6,200 annotated open reading frames (ORFs). However, the predictive power of bioinformatic analysis is limited, and putting the role of these genes into a biological context will require more definitive functional approaches. We present here a strategy for genetic analysis of S. meliloti on a genomic scale and report the successful implementation of the first step of this strategy by constructing a set of plasmids representing 100% of the 6,317 annotated ORFs cloned into a mobilizable plasmid by using efficient PCR and recombination protocols. By using integrase recombination to insert these ORFs into other plasmids in vitro or in vivo (B. L. House et al., Appl. Environ. Microbiol. 70:2806-2815, 2004), this ORFeome can be used to generate various specialized genetic materials for functional analysis of S. meliloti, such as operon fusions, mutants, and protein expression plasmids. The strategy can be generalized to many other genome projects, and the S. meliloti clones should be useful for investigators wanting an accessible source of cloned genes encoding specific enzymes.


Assuntos
Clonagem Molecular/métodos , Biologia Computacional/métodos , Genoma Bacteriano , Fases de Leitura Aberta/genética , Recombinação Genética , Sinorhizobium meliloti/genética , Proteínas de Bactérias/genética , Primers do DNA , Bases de Dados Genéticas , Técnicas Genéticas , Genômica , Plasmídeos , Reação em Cadeia da Polimerase
15.
Solid State Nucl Magn Reson ; 27(3): 155-64, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15681132

RESUMO

Periodic ab initio HF calculations using the CRYSTAL code have been used to calculate (23)Na NMR quadrupole parameters for a wide range of crystalline sodium compounds including Na(3)OCl. An approach is developed that can be used routinely as an alternative to point-charge modelling schemes for the assignment of distinct lines in (23)Na NMR spectra to specific crystallographic sodium sites. The calculations are based on standard 3-21 G and 6-21 G molecular basis sets and in each case the same modified basis set for sodium is used for all compounds. The general approach is extendable to other quadrupolar nuclei. For the 3-21 G calculations a 1:1 linear correlation between experimental and calculated values of C(Q)((23)Na) is obtained. The 6-21 G calculations, including the addition of d-polarisation functions, give better accuracy in the calculation of eta((23)Na). The sensitivity of eta((23)Na) to hydrogen atom location is shown to be useful in testing the reported hydrogen-bonded structure of Na(2)HPO(4).


Assuntos
Algoritmos , Cristalografia/métodos , Espectroscopia de Ressonância Magnética/métodos , Modelos Químicos , Compostos de Sódio/análise , Compostos de Sódio/química , Simulação por Computador , Cristalização/métodos , Pós , Isótopos de Sódio/análise , Isótopos de Sódio/química
16.
Appl Environ Microbiol ; 70(5): 2806-15, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15128536

RESUMO

The availability of bacterial genome sequences has created a need for improved methods for sequence-based functional analysis to facilitate moving from annotated DNA sequence to genetic materials for analyzing the roles that postulated genes play in bacterial phenotypes. A powerful cloning method that uses lambda integrase recombination to clone and manipulate DNA sequences has been adapted for use with the gram-negative alpha-proteobacterium Sinorhizobium meliloti in two ways that increase the utility of the system. Adding plasmid oriT sequences to a set of vehicles allows the plasmids to be transferred to S. meliloti by conjugation and also allows cloned genes to be recombined from one plasmid to another in vivo by a pentaparental mating protocol, saving considerable time and expense. In addition, vehicles that contain yeast Flp recombinase target recombination sequences allow the construction of deletion mutations where the end points of the deletions are located at the ends of the cloned genes. Several deletions were constructed in a cluster of 60 genes on the symbiotic plasmid (pSymA) of S. meliloti, predicted to code for a denitrification pathway. The mutations do not affect the ability of the bacteria to form nitrogen-fixing nodules on Medicago sativa (alfalfa) roots.


Assuntos
Recombinação Genética , Sinorhizobium meliloti/genética , Acetileno/metabolismo , Sequência de Bases , Conjugação Genética , DNA Nucleotidiltransferases/genética , DNA Nucleotidiltransferases/metabolismo , Escherichia coli/genética , Deleção de Genes , Medicago sativa/microbiologia , Dados de Sequência Molecular , Fixação de Nitrogênio , Oxirredução , Plasmídeos/genética
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