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1.
Langmuir ; 35(22): 7155-7160, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31050434

RESUMO

High-resolution inkjet printing of a hydrophobic polymer surface (polystyrene, PS) was accomplished using a patterned coating of cellulose nanocrystals (CNCs) that prevents the ink from bleeding. A periodically crack-free, wrinkled (wavelength of around 850 nm) stamp was prepared by surface oxidation of an uniaxially stretched poly(dimethylsiloxane) elastomeric substrate and was used as a template to transfer aligned patterns of cellulose nanocrystals (CNCs) onto PS surfaces by wet stamping. The morphology of the aligned CNC coatings on PS was then compared with randomly deposited CNCs on PS using atomic force microscopy. The wettability of the CNCs and polymer surfaces with water and ink was measured and analyzed in the context of inkjet printing. This biomaterial coating technique enables high-resolution printing of modern water-based inks onto hydrophobic surfaces for applications in renewable packaging and printing of biomolecules for high throughput diagnostics. Further, with suitable modifications, the technology is scalable to roll-to-roll manufacturing for industrial flexo printing.

2.
Ergonomics ; 61(10): 1395-1408, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29799358

RESUMO

The present study evaluated three automation modes for improving performance in an X-ray luggage screening task. One hundred and forty participants were asked to detect the presence of prohibited items in X-ray images of cabin luggage. Twenty participants conducted this task without automatic support (control group), whereas the others worked with either indirect cues (system indicated the target presence without specifying its location), or direct cues (system pointed out the exact target location) or adaptable automation (participants could freely choose between no cue, direct and indirect cues). Furthermore, automatic support reliability was manipulated (low versus high). The results showed a clear advantage for direct cues regarding detection performance and response time. No benefits were observed for adaptable automation. Finally, high automation reliability led to better performance and higher operator trust. The findings overall confirmed that automatic support systems for luggage screening should be designed such that they provide direct, highly reliable cues.Practitioner summary: The present study confirmed previous findings showing better detection performance in X-ray images of luggage when supported by automation providing direct, highly reliable cues. Furthermore, participants used adaptable automation only to select their preferred level of automation. This behaviour did not provide the benefits expected under adaptable automation.


Assuntos
Aeroportos , Automação , Radiografia , Medidas de Segurança , Adolescente , Adulto , Feminino , Humanos , Masculino , Visão Ocular , Adulto Jovem
3.
Sci Total Environ ; 912: 169298, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38128653

RESUMO

Border fences have severely impeded the transboundary migration of a number of large mammals worldwide, with central Asia being one of the most impacted. The Marco Polo sheep (Ovis ammon polii), an iconic species of Pamir, is threatened in its transboundary movement by increasing border fencing among their five distributed countries, including Tajikistan, Kyrgyzstan, China, Afghanistan, and Pakistan. In this study, by building ensemble species distribution models, we found that eastern Tajikistan had the largest suitable Macro Polo sheep habitat (about 42 % of the total suitable habitat), followed by China (about 32 %). We used least-cost paths to identify 51 ecological corridors including 5 transboundary ecological corridors, which may be important to maintain connectivity in both domestic and transboundary regions. To assess the potential barrier effect of border fences, we assessed four scenarios (30, 40, 50 and 60°) corresponding to the upper limit of the slope for the construction of fences. In areas too steep for fencing, these could be used by wild sheep to cross barriers or borders and may represent migration or movement routes, defined as natural passages. In the most pessimistic Scenario 60, only 25 migratory passages along the border fences were identified, compared to 997 in the most optimistic scenario (Scenario 30), indicating a strong negative effect of intensive border fencing on the transboundary movement of Marco Polo sheep. The establishment of transnational conservation parks, and ensuring permeability is maintained in key areas, could have a positive impact on the connectivity and persistence of Marco Polo sheep populations, and provide important lessons for other large migratory mammals in transboundary regions.


Assuntos
Ecossistema , Mamíferos , Animais , Ovinos , China , Afeganistão , Quirguistão , Conservação dos Recursos Naturais
4.
Emerg Infect Dis ; 17(12): 2338-41, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22172532
5.
Appl Ergon ; 82: 102916, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31422292

RESUMO

This study investigated the effects of cue plausibility in a baggage screening task. 120 participants had to indicate whether a prohibited item was present in a series of grey-scaled X-ray images of baggage. They were assisted by a support system, which pointed at the location of a suspicious object. A 2 × 2 × 2 between-subjects design was used. Cue plausibility for false alarms (i.e. how the cued object was similar to a prohibited item) and support system reliability were manipulated at two levels (high/low). Furthermore, half of participants were provided with a rationale about automation failures (RAF) to reduce their negative impact on trust and performance. The results showed lower performance and more compliance with automation suggestions when cues were implausible than plausible. The RAF increased the response time and did not improve detection performance. Overall, this suggests that effective (computer-based) training is needed to reduce the negative effect of plausible cues.


Assuntos
Aeroportos , Automação , Tomada de Decisões , Radiografia , Medidas de Segurança , Adulto , Sinais (Psicologia) , Enganação , Feminino , Humanos , Masculino , Tempo de Reação , Reprodutibilidade dos Testes , Treinamento por Simulação , Análise e Desempenho de Tarefas , Confiança
6.
Front Psychol ; 10: 256, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30837917

RESUMO

X-ray screening of passenger baggage is a key component in aviation security. The current study investigated how experts and novices performed in an X-ray baggage screening task while being assisted by an adaptable diagnostic aid. Furthermore, it examined how both groups operated and trusted this automated system. 30 experts (certified screeners) and 31 novices (students) had to indicate whether a target item (either a knife or a gun) was present in a series of X-ray images of cabin baggage. Half of the participants could choose between three different support levels of the diagnostic aid (DA): (1) no support, (2) a cue indicating the presence of a potential target without locating it, or (3) a cue indicating the presence of a potential target by surrounding it with a red frame. As expected, experts achieved higher detection performance (d'), were more self-confident and felt more competent in achieving the task than novices. Furthermore, experts experienced less time pressure and fatigue. Although both groups used the DA in a comparable way (in terms of support level used and frequency of level switches), results showed a performance increase for novices working with the DA compared to novices without support. This benefit of DA was not observed for experts. Interestingly, despite no difference in perceived trust ratings, experts were more compliant (i.e., following DA recommendations when it indicated the presence of a target) and reliant (i.e., following DA recommendations when it indicated the absence of a target) than novices. Altogether, the results of the present study suggested that novices benefited more from a DA than experts. Furthermore, compliance and reliance on DA seemed to depend on expertise with the task. Since experts should be better at assessing the reliability of the DA than novices, they may have used the DA as 'back-up' to confirm their decisions based on expertise (confirmatory function), while novices may have used it as a guide to base their decisions on (support function). Finally, trust towards a DA was associated with the degree to which participants found the DA useful.

7.
Appl Ergon ; 79: 66-75, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31109463

RESUMO

This study investigated whether there is empirical support for the current EU regulation mandating breaks of at least 10 min after each period of 20 min continuously reviewing X-ray images in airport security screening. As a second goal, it examined whether providing more autonomy to airport security officers (in the form of spontaneous rest breaks and adaptable automation) would improve their performance and subjective state. Seventy-two student participants had to indicate the presence (or absence) of a threat item (either a gun or a knife) in a series of grey-scaled X-ray images of cabin baggage. Three work-rest schedules were examined: spontaneous breaks (i.e. participants could take breaks at any time), two 5-min breaks and two 10-min breaks during a 1-h testing session. Furthermore, half of the participants were assisted in their task by an adaptable support system offering three levels of automation: (1) no support, (2) cues indicating the presence of a potential threat item, and (3) cues indicating the exact location of a potential threat item. Results showed no performance differences between break regimes, which suggests that there may be viable alternatives to the current EU regulations. It also emerged that providing participants with adaptable automation did not lead to better detection performance but resulted in a less positive response bias than participants without automatic support. Implications for current aviation security regulations are discussed.


Assuntos
Aeroportos , Automação/métodos , Admissão e Escalonamento de Pessoal , Medidas de Segurança/organização & administração , Trabalho/psicologia , Adulto , Simulação por Computador , Feminino , Humanos , Masculino , Saúde Ocupacional , Descanso/psicologia , Análise e Desempenho de Tarefas , Tolerância ao Trabalho Programado , Carga de Trabalho , Adulto Jovem
8.
Anal Bioanal Chem ; 391(5): 1739-49, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18197401

RESUMO

Axisymmetric drop shape analysis-profile (ADSA-P) was combined with total reflectometric interference spectroscopy (TRIS) in one experimental setup to study the interfacial phenomena at solid-liquid and liquid-vapor interfaces caused by adsorption/desorption (dissolution) of surface-active substances. Using sessile liquid droplets on polymer film/chromium-coated glass substrates that were optically matched with an immersion oil to a TRIS reflection prism, the optical thickness (product of physical thickness d and refractive index n) of the polymer film can be estimated by evaluating the wavelength-dependent intensity of reflected light. The sessile droplet is analyzed simultaneously by an ADSA setup arranged in a transverse direction to the path of the white-light beam of TRIS. From this analysis, the solid-vapor interfacial tension gamma (lv)(t), contact angle theta(t), contact radius r(t), drop volume V(t), and solid-liquid interfacial tension gamma (sl)(t) can be monitored as a function of time. The new method was applied to study polystyrene and poly(4-hydroxystyrene) surfaces in contact with aqueous buffer solutions and with protein solutions. The time-dependent changes in the optical film thickness caused by the adsorption of human serum albumin (HSA) and lysozyme (LSZ) were accompanied by changes in the solid-liquid interfacial tension. From the detailed study of both parameters, conclusions can be drawn with regard to the adsorption kinetics of the proteins on the hydrophobic polystyrene surfaces and to conformational changes occurring within the adsorbed protein layers.

9.
Ecol Evol ; 8(10): 5124-5138, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29876087

RESUMO

Identifying the factors predicting the high-elevation suitable habitats of Central Asian argali wild sheep and how these suitable habitats are affected by the changing climate regimes could help address conservation and management efforts and identify future critical habitat for the species in eastern Tajikistan. This study used environmental niche models (ENMs) to map and compare potential present and future distributions of suitable environmental conditions for Marco Polo argali. Argali occurrence points were collected during field surveys conducted from 2009 to 2016. Our models showed that terrain ruggedness and annual mean temperature had strong correlations on argali distribution. We then used two greenhouse gas concentration trajectories (RCP 4.5 and RCP 8.5) for two future time periods (2050 and 2070) to model the impacts of climate change on Marco Polo argali habitat. Results indicated a decline of suitable habitat with majority of losses observed at lower elevations (3,300-4,300 m). Models that considered all variables (climatic and nonclimatic) predicted losses of present suitable areas of 60.6% (6,928 km2) and 63.2% (7,219 km2) by 2050 and 2070, respectively. Results also showed averaged habitat gains of 46.2% (6,106 km2) at much higher elevations (4,500-6,900 m) and that elevational shifts of habitat use could occur in the future. Our results could provide information for conservation planning for this near threatened species in the region.

10.
Heliyon ; 3(11): e00445, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29159323

RESUMO

We modeled summer and winter habitat suitability of Marco Polo argali in the Pamir Mountains in southeastern Tajikistan using these statistical algorithms: Generalized Linear Model, Random Forest, Boosted Regression Tree, Maxent, and Multivariate Adaptive Regression Splines. Using sheep occurrence data collected from 2009 to 2015 and a set of selected habitat predictors, we produced summer and winter habitat suitability maps and determined the important habitat suitability predictors for both seasons. Our results demonstrated that argali selected proximity to riparian areas and greenness as the two most relevant variables for summer, and the degree of slope (gentler slopes between 0° to 20°) and Landsat temperature band for winter. The terrain roughness was also among the most important variables in summer and winter models. Aspect was only significant for winter habitat, with argali preferring south-facing mountain slopes. We evaluated various measures of model performance such as the Area Under the Curve (AUC) and the True Skill Statistic (TSS). Comparing the five algorithms, the AUC scored highest for Boosted Regression Tree in summer (AUC = 0.94) and winter model runs (AUC = 0.94). In contrast, Random Forest underperformed in both model runs.

11.
J Clin Virol ; 74: 32-6, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26655265

RESUMO

BACKGROUND: Previous studies have indicated that the absence of serum antibodies to influenza A H1N1 virus on day 4 after onset of symptoms predicted a fatal outcome in patients critically ill with influenza. The underlying mechanism was suggested to be the trapping of anti-influenza antibodies in pulmonary immune complexes. OBJECTIVES: To study serum and mucosal antibodies as prognostic markers in patients with severe influenza A H1N1 infection. STUDY DESIGN: Blood and respiratory samples (n=324) from 12 patients with severe influenza were analysed for anti-H1N1 antibodies with and without immune complex dissociation from symptom onset until convalescence or death (follow up 14-169 days). Eleven healthy subjects were analysed for comparison. RESULTS: One of the 12 patients died from influenza pneumonia and had no detectable anti-H1N1 serum antibodies. However, also 2 of the 11 surviving patients remained negative for anti-H1N1 serum antibodies during follow-up (20 and 41 days, respectively). In six of the 11 survivors serum antibodies on day 4 were negative, but turned positive between day 7 and 23. In the remaining 3 patients antibodies were detected in the first 4 days of illness. Mucosal IgG or IgA was detected in all of the patients regardless of their clinical outcome and in 4 of 11 healthy subjects. No mucosal immune complexes were found in the patient who died but were detected in 3 of the 11 survivors. CONCLUSIONS: This study suggests that no prognostic conclusions can be drawn from anti-H1N1 serum and mucosal antibodies in patients with severe influenza.


Assuntos
Anticorpos Antivirais/análise , Biomarcadores/análise , Imunidade nas Mucosas , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Soro/imunologia , Adulto , Feminino , Humanos , Lactente , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
12.
Front Hum Neurosci ; 7: 654, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24151457

RESUMO

This paper describes a study where a new X-ray machine for security screening featuring motion imaging (i.e., 5 views of a bag are shown as an image sequence) was evaluated and compared to single view imaging available on conventional X-ray screening systems. More specifically, it was investigated whether with this new technology X-ray screening of passenger bags could be enhanced to such an extent that laptops could be left inside passenger bags, without causing a significant impairment in threat detection performance. An X-ray image interpretation test was created in four different versions, manipulating the factors packing condition (laptop and bag separate vs. laptop in bag) and display condition (single vs. motion imaging). There was a highly significant and large main effect of packing condition. When laptops and bags were screened separately, threat item detection was substantially higher. For display condition, a medium effect was observed. Detection could be slightly enhanced through the application of motion imaging. There was no interaction between display and packing condition, implying that the high negative effect of leaving laptops in passenger bags could not be fully compensated by motion imaging. Additional analyses were carried out to examine effects depending on different threat categories (guns, improvised explosive devices, knives, others), the placement of the threat items (in bag vs. in laptop) and viewpoint (easy vs. difficult view). In summary, although motion imaging provides an enhancement, it is not strong enough to allow leaving laptops in bags for security screening.

13.
Langmuir ; 24(21): 12603-11, 2008 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-18828614

RESUMO

The surface properties of poly(dimethyl siloxane) (PDMS) layers screen printed onto silicon wafers were studied after oxygen and ammonia plasma treatments and subsequent grafting of poly(ethylene -alt-maleic anhydride) (PEMA) using X-ray photoelectron spectroscopy (XPS), roughness analysis, and contact angle and electrokinetic measurements. In the case of oxygen-plasma-treated PDMS, a hydrophilic, brittle, silica-like surface layer containing reactive silanol groups was obtained. These surfaces indicate a strong tendency for "hydrophobic recovery" due to the surface segregation of low-molecular-weight PDMS species. The ammonia plasma treatment of PDMS resulted in the generation of amino-functional surface groups and the formation of a weak boundary layer that could be washed off by polar liquids. To avoid the loss of the plasma modification effect and to achieve stabilization of the mechanically instable, functionalized PDMS top layer, PEMA was subsequently grafted directly or after using gamma-APS as a coupling agent on the plasma-activated PDMS surfaces. In this way, long-time stable surface functionalization of PDMS was obtained. The reactivity of the PEMA-coated PDMS surface caused by the availability of anhydride groups could be controlled by the number of amino functional surface groups of the PDMS surface necessary for the covalent binding of PEMA. The higher the number of amino functional surface groups available for the grafting-to procedure, the lower the hydrophilicity and hence the lower the reactivity of the PEMA-coated PDMS surface. Additionally, pull-off tests were applied to estimate the effect of surface modification on the adhesion between the silicone rubber and an epoxy resin.

14.
Langmuir ; 20(19): 8096-102, 2004 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-15350078

RESUMO

The influence of hyperbranched polyesters with different functional end groups on the surface tension of mixtures with an oligo(ester diol) was investigated. The temperature dependence of the surface tension of the pure components and of the mixtures was measured by a modified Wilhelmy balance technique. The results indicate that the surface tension of the pure hyperbranched polyesters strongly depends on the functionality of the end groups. The functionalization of the hydroxyl end groups by short alkyl chains (methyl, tert-butyl) reduced the surface tension depending on the degree of substitution. The surface tension of the mixtures with the hydroxyl-terminated hyperbranched polyester was slightly increased at higher concentrations of the hyperbranched polymer compared to the surface tension of the pure ester diol. On the other hand, the surface tension of mixtures could be considerably decreased using 1% of hyperbranched polyester polyols partially substituted with short alkyl chains. In that case, the modified hyperbranched polyesters act as surface active agents. On the molecular level, the enrichment of the modified hyperbranched polyester in the surface region was proven by X-ray photoelectron spectroscopy measurements.


Assuntos
Poliésteres/química , Polímeros/química , Estrutura Molecular , Tensão Superficial , Temperatura , Fatores de Tempo
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