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Model development activities are increasing in pavement research and engineering applications. At the same time, there is ambiguity and a lack of consistency with regard to checking and quantifying credibility and suitability for the intended application. Specifically, usage of the terms Verification and Validation (V&V) is seen to vary across contributions. In this context, this paper was motivated by the desire to provide a best-practice reference that underlines the significance of the V&V terms, clarifies their definition, and promotes a more unified usage. Accordingly, the objective was to offer examples that introduce the V&V jargon, demonstrate basic V&V concepts and processes, and highlight certain fine points. A total of five distinct models were introduced and discussed: (1) load-related responses in asphalt pavements, (2) load-related responses in concrete pavements, (3) crack initiation and propagation in asphalt concrete, (4) linear viscoelasticity of asphalt concrete, and (5) water flow through asphalt concrete pores. A general conclusion from this work is that successful V&V efforts are closely linked to a clear definition of the intended usage, i.e., the specific reality of interest being targeted by the model. It is also concluded that documenting V&V efforts is integral to any computational model development. Doing so communicates to potential users the region of confidence for the model alongside the expected differences with the reality of interest. [ABSTRACT FROM AUTHOR]

Electric vehicles offer higher acceleration than conventional internal combustion engines due to larger engine torque. The design and placement of battery packs in heavy-duty electric vehicles are still being optimized, as they can affect axle load distributions and consequently impact pavement analysis and design. This study presents a finite element model of a dual tire assembly considering varying load and acceleration conditions to investigate the effect of conventional and electric heavy-duty vehicles on tire–pavement contact forces. Three scenarios for battery pack locations were examined, leading to six loading conditions for both internal combustion engines and electric trucks. The resulting 3D contact forces, compared at a specific line of points along the contact patch and throughout the entire distribution via kernel density estimate, determined that the load increase due to battery location had a much greater impact than the change in torque for both internal combustion engine and electric trucks provided they are at the same rolling condition. Higher loads altered the vertical and longitudinal contact forces and led to a broader contact area. On the other hand, transverse contact forces showed the least variation, although this may differ under cornering scenarios. Finally, a higher slip ratio exacerbated the contact forces in the traveling direction, highlighting the importance of considering rolling conditions in future analyses of pavement damage caused by heavy-duty electric vehicles. Practical Applications: Truck loading usually governs pavement design, layer thicknesses, and corresponding materials while considering local environmental conditions. For flexible pavements, in particular, the details of the distribution of the forces at the tire–pavement interface play a significant role in driving failure near the pavement surface. As the electrification of heavy-duty truck platoons becomes a reality, it is paramount for pavement engineers to quantify the effect of the torque and battery location from electric trucks on contact forces and evaluate its impact on flexible pavements—this paper provides such quantification. The study found that battery location, rather than increased torque, is the controlling variable for the electric trucks due to increased load influence on vertical contact forces. [ABSTRACT FROM AUTHOR]

Anodic aluminum oxide (AAO) membranes were used as templates to control orientation of an ionchannel forming columnar mesophase obtained by self assembly of a wedge-shaped sulfonate molecule. Inside the AAO structure, the director vector of the mesophase is oriented parallel to the pore axis due to the confinement effect. The molecular arrangement induced by the spatial confinement within the pores is extended over several microns into the remnant film on the AAO surface. The homeotropic alignment of the channels promotes unidimensional ion conduction through the film plane, which is manifested by a considerable increase in conductivity relative to isotropic samples. [ABSTRACT FROM AUTHOR]

Recent technological advances enable gripper-equipped robots to perform many tasks traditionally associated with the human hand, allowing the use of grippers in a wide range of applications. Depending on the application, an ideal gripper design should be affordable, energy-efficient, and adaptable to many situations. However, regardless of the number of grippers available on the market, there are still many tasks that are difficult for grippers to perform, which indicates the demand and room for new designs to compete with the human hand. Thus, this paper provides a comprehensive review of robotic arm grippers to identify the benefits and drawbacks of various gripper designs. The research compares gripper designs by considering the actuation mechanism, degrees of freedom, grasping capabilities with multiple objects, and applications, concluding which should be the gripper design with the broader set of capabilities. [ABSTRACT FROM AUTHOR]

The number of individuals with upper or lower extremities dysfunction (ULED) has considerably increased in the past few decades, resulting in a high economic burden for their families and society. Individuals with ULEDs require assistive robots to fulfill all their activities of daily living (ADLs). However, a theory for the optimal design of assistive robots that reduces energy consumption while increasing the workspace is unavailable. Thus, this research presents an algorithm for the optimal link length selection of an assistive robot mounted on a wheelchair to minimize the torque demands of each joint while increasing the workspace coverage. For this purpose, this research developed a workspace to satisfy a list of 18 ADLs. Then, three torque indices from the literature were considered as performance measures to minimize; the three torque measures are the quadratic average torque (QAT), the weighted root square mean (WRMS), and the absolute sum of torques (AST). The proposed algorithm evaluates any of the three torque measures within the workspace, given the robot dimensions. This proposed algorithm acts as an objective function, which is optimized using a genetic algorithm for each torque measure. The results show that all tree torque measures are suitable criteria for assistance robot optimization. However, each torque measures yield different optimal results; in the case of the QAT optimization, it produces the least workspace with the minimum overall torques of all the joints. Contrarily, the WRMS and AST optimization yield similar results generating the maximum workspace coverage but with a greater overall torque of all joints. Thus, the selection between the three methods depends on the designer's criteria. Based on the results, the presented methodology is a reliable tool for the optimal dimensioning of assistive robots. [ABSTRACT FROM AUTHOR]

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This paper quantifies the relevance of restriction to joint rotation of an airfield concrete pavement when calculating critical curling stresses and deflections using a validated finite element model. The validation uses strains measured at the John F. Kennedy International Airport. To calculate critical curling stresses and deflections, the pavement was subjected to 5263 h of temperature variation determined by utilising the enhanced integrated climate model and thermocouple readings. The profiles include a wide range of average temperatures, temperature gradients, and temperature nonlinearity. Three conditions were included: (1) joints free to displace and rotate; (2) joints free to rotate, but partially restrained to vertical displacement; and (3) joints partially restrained to vertical displacement and rotation. Differences in critical stresses between the second and third conditions were greater than 5% for 70% of the time. When considering rotational restriction, critical deflections are reduced. Eighty percent of the difference, with respect to the free case, was caused by rotational restriction. It was evident that joint rotation intensifies the influence of curling stresses and deflections on long-term performance of airfield rigid pavement. [ABSTRACT FROM AUTHOR]

The use of nanostructured materials and nanosized‐topographies has the potential to impact the performance of implantable biodevices, including neural interfaces, enhancing their sensitivity and selectivity, while reducing tissue reactivity. As a result, current trends in biosensor technology require the effective ability to improve devices with controlled nanostructures. Nanoimprint lithography to pattern surfaces with high‐density and high aspect ratio nanopillars (NPs) made of polystyrene (PS‐NP, insulating), or of a polystyrene/carbon‐nanotube nanocomposite (PS‐CNT‐NP, electrically conductive) are exploited. Both substrates are challenged with cultured primary neurons. They are demonstrated to support the development of suspended synaptic networks at the NPs' interfaces characterized by a reduction in proliferating neuroglia, and a boost in neuronal emergent electrical activity when compared to flat controls. The authors successfully exploit their conductive PS‐CNT‐NPs to stimulate cultured cells electrically. The ability of both nanostructured surfaces to interface tissue explants isolated from the mouse spinal cord is then tested. The integration of the neuronal circuits with the NP topology, the suspended nature of the cultured networks, the reduced neuroglia formation, and the higher network activity together with the ability to deliver electrical stimuli via PS‐CNT‐NP reveal such platforms as promising designs to implement on neuro‐prosthetic or neurostimulation devices. [ABSTRACT FROM AUTHOR]

Closed-form expressions for calculating stresses and displacements of partially restrained concrete pavement caused by a linear temperature gradient are presented. Translational and rotational linear elastic springs along the slab edges defined the partial restraint. In addition to plate theory behavior, the model assumes linear elastic concrete and an infinitely long slab resting on a Winkler foundation. The solutions of curling stresses and displacements were validated using the finite-element (FE) method and quantified the effect of semirigid connections, slab and foundation material properties, and slab thickness and width on them. Rotational and translational restraints, which can be related to joint condition in concrete pavement, had significant influence on the magnitude and location of maximum curling stresses and deflections. In addition, Westergaard analysis, a particular case of the proposed solution when there is no restriction along the slab's edges, resulted into the largest deflections at the center of the slab and the lowest maximum curling stresses. Adjustment factors that convert the theoretical findings from an infinitely long slab to a square slab are proposed. [ABSTRACT FROM AUTHOR]

Water management policies and their impacts for both the Basin of Mexico and the Lerma-Chapala basin-where nearly 25% of Mexico's inhabitants are found-are described. This work shows that the prevailing water management policy has been the augmentation of water supply and neither policies have focused on water savings nor management of water demand. The effects of the large extraction rates on both basins have caused drying-up of streams due to drawdown rates that reach 2.5 m/year with an associated land subsidence in different cities in these basins. Water management in Mexico needs to change from a water supply approach to a water efficiency approach, where water needs to be efficiently used. Water management will only improve when policies consider both technical and social perspectives. WIREs Water 2018, 5:e1247. doi: 10.1002/wat2.1247 For further resources related to this article, please visit the . [ABSTRACT FROM AUTHOR]

Sudden wind shifts caused by atmospheric gust fronts can lead to firefighter entrapments and fatalities. In this study, we describe the physical processes involved in the related phenomena of convective downdrafts, gust fronts and downbursts. We focus on the dominant process, evaporative cooling in a dry surface layer, as characterised by the measure known as downdraft maximum available potential energy (DMAPE). We present a climatological analysis of DMAPE for the coterminous United States, developed from the Climate Forecast System Reanalysis data for the period 1979-2008. Diurnal and seasonal patterns are described. We conclude with a discussion of the implications and limitations of the analysis and DMAPE as an indicator of gust front strength or downburst occurrence. [ABSTRACT FROM AUTHOR]

The Mechanistic-empirical pavement design guide (MEPDG) provides theoretically superior methodology, as compared with its predecessor, for the design and analysis of pavement structures. The mechanistic part refers to simulating pavement--tire interaction to calculate critical responses within pavement. The empirical part means prediction of pavement distress propagation over time using transfer functions that link a critical pavement response to a particular pavement distress. The mechanistic part of MEPDG simulates tire--pavement interaction in three steps: subdivision of pavement layers; complex modulus calculation at the middepth of each sublayer, considering velocity and temperature; and running the multilayered elastic theory (MLET) software, JULEA. Although MEDPG has a grounded methodology for pavement analysis, it has a number of limitations and unrealistic simplifications that result in inaccurate response predictions. These limitations are primarily related to the pavement analysis approach used in the MEPDG framework, MLET. By contrast, finite-element (FE) analysis has proven to be a promising numerical approach for overcoming these limitations and simulating pavement more accurately and realistically. Although comparison of MLET with FE analysis has been studied, the difference between FE and MEPDG simulations has not been quantified. This study fills that gap by developing linear equations that connect pavement responses produced by these two approaches to pavement analysis. The equations are developed for ten different pavement responses, using a total of 336 cases simulated using FE and MEPDG analyses. The cases modeled in simulations were selected to capture extreme conditions, i.e., thick and thin pavement structures with strong and weak material properties. The equations developed can help pavement researchers understand quantitatively the effect of MEPDG limitations. In addition, the equations may be used as adjustment factors for MEPDG to compute pavement responses more realistically without using computationally expensive approaches, such as FE analysis. [ABSTRACT FROM AUTHOR]

Cacao beans belong to key agricultural crops on global scale, yet their production faces a dramatic fall in the capacity coupled with increasing global demand, often denominated as "the cacao crisis". The fall of production of this crop in Mexican agriculture can be emblematic for global production. The country where cacao beans were first domesticated, is experiencing a vertiginous drop of plantation surface thus creating a serious concern not only for diversity of local production, but also for genetic and historical legacy as plantations are ebbing away due to substitution of cacao plantations with more rentable commercial crops. The paper tries to answer the question on the motives behind such a decrease on the base of data stemming from cacao producers of Tabasco region applying the lens of social capital and derives the conclusion that a collective action fuelled by social capital may be crucial for prosperity of the plantations. Collaboration and knowledge sharing thus may be of more importance for the future of cacao production than the fight against a single cause believed to be the fall of production such as the invasion of Moniliophthora roreri fungus. [ABSTRACT FROM AUTHOR]

Calculation of truck tires rolling resistance, using the finite element method and considering variables such as incompressible visco-hyperelastic rubber materials, accurate tire geometry and steady temperature distribution, is presented. The model was validated using experimentally measured contact area and contact stresses. Rolling resistance was calculated for three values of axle load, tire inflation pressure, temperature and speed. In addition, regression analysis was used to propose a mathematical expression for predicting rolling resistance as a function of the considered variables. Finally, the contribution of tire’s rubber components to the internal energy was quantified, and it was found that sidewall and subtread were the most relevant. The results of this study will help differentiate the contribution of pavement parameters, such as mean profile depth and international roughness index, to fuel efficiency. [ABSTRACT FROM PUBLISHER]

The interaction between deformable tires and pavements was studied using finite-element modeling and a semicoupled approach. Three finite-element models were used: (1) a hyperelastic tire rolling on an infinitely rigid surface; (2) a three-dimensional pavement model; and (3) a hyperelastic tire rolling on a deformable viscoelastic body. The tire and pavement models have been successfully compared with experimental measurements. Tire interaction with a rigid surface provided contact stresses to excite the pavement model, and results of the pavement model defined the boundary conditions of the tire rolling on the deformable body. After that, the pavement loaded with the contact stresses from the tire interacting with the deformable body was run. This study focuses on issues related to pavement damage (tire-pavement contact stresses and critical pavement responses) and lifecycle assessment (rolling resistance). Transverse contact stresses were the most affected by pavement deformation, which translated into impact on the maximum vertical strain and the maximum shear strain in the asphalt concrete layer. The tire moving on a deformable body showed that the thin pavement created a higher rolling resistance force than thick pavements. In addition, dissipation-based and deflection-based approaches for calculating pavement contribution to rolling resistance were equivalent. Finally, for the range of values considered, changes in tire inflation pressure affected the rolling resistance force more than changes in applied load. [ABSTRACT FROM AUTHOR]

The finite-element method was used to quantify the effect of temperature and speed on contact area, deflection, and three-dimensional contact stresses of a free-rolling wide-base tire. The tire model comprised material properties identified in the laboratory and/or provided by the tire manufacturer (hyperviscoelastic rubber and linear elastic reinforcement) and accurate geometry. The model was validated using measured deflection and contact area. The analysis matrix consisted of 81 cases resulting from a combination of three loads, tire-inflation pressures, speeds, and temperatures. Four criteria were used to compare contact stresses: range, average, root-mean-square error, and coefficient of determination. Speed and temperature influence the contact area more than deflection. Longitudinal contact stresses were the most affected, followed by transverse contact stresses. In general, under constant load and tire-inflation pressure, the influence of temperature was more significant on the considered output variables than the effect of speed. [ABSTRACT FROM AUTHOR]

The self-assessment of quality plays a strategic role when it comes to direct or govern the use of Information Technology (IT) in a telecommunications organization. Due to its importance, it is essential to start out from a relational determination between models to suit it to the organizational reality. This work of exploratory and documentary research addresses the quality in the use of IT from the perspective of the Iberoamerican excellence model and the ISO 38500 standard, based on the knowledge about the high use that IT represents in the organization strategy. [ABSTRACT FROM PUBLISHER]

There is little information on how urban forest ecosystems in South America and Mediterranean climates change across both space and time. This study statistically and spatially analyzed the spatio-temporal dynamics of Santiago, Chile's urban forest using tree and plot-level data from permanent plots from 2002 to 2014. We found mortality, ingrowth, and tree cover remained stable over the analysis period and similar patterns were observed for basal area (BA) and biomass. However, tree cover increased, and was greater in the highest socioeconomic stratum neighborhoods while it dropped in the medium and low strata. Growth rates for the five most common tree species averaged from 0.12 to 0.36 cm· year–1. Spatially, tree biomass and BA were greater in the affluent, northeastern sections of the city and in southwest peri-urban areas. Conversely, less affluent central, northwest, and southern areas showed temporal losses in BA and biomass. Overall, we found that Santiago's urban forest follows similar patterns as in other parts of the world; affluent areas tend to have more and better managed urban forests than poorer areas, and changes are primarily influenced by social and ecological drivers. Nonetheless, care is warranted when comparing urban forest structural metrics measured with similar sampling-monitoring approaches across ecologically disparate regions and biomes. [ABSTRACT FROM AUTHOR]

Description of tire model development using the finite element (FE) method is presented. Three-dimensional tire-pavement contact stresses were predicted for braking, traction, and free rolling using the FE method. Measured load-deflection curves, contact area, and contact stresses were used for model outcome validation. Slide-velocity-dependent friction and accurate input regarding geometry and material properties were considered. The developed tire model, which helped in studying contact stresses variation in each direction, was used to explain the various phenomena taking place at the tire-pavement interface during straight-line rolling. The analysis matrix includes nine rolling conditions and various loads, tire inflation pressures, and speeds. Vertical contact stresses were not significantly affected by speed or slip ratio; however, contact stresses were greatly modified along the in-plane directions by rolling conditions. Analytical expressions were introduced to represent vertical and longitudinal contact stresses for full braking and full traction. Formulas are presented for low speed and full braking, which are relevant for roadway intersections design. [ABSTRACT FROM AUTHOR]

A post hoc analysis of safety data from study protocol NZT40012 assessed the incidence of conditions defined by the Centers for Disease Control and Prevention in 86 zidovudine-naïve, antiretroviral-experienced patients with HIV-1 infection who responded poorly (plasma HIV-1 RNA > 1000 copies/mL) despite at least 4 months' treatment with stavudine-containing regimens. Peripheral neuropathy occurred in 21%; other conditions were seen less frequently (candidiasis [13%], herpes zoster [12%], diarrhea lasting > 1 month [9%], Pneumocystis carinii pneumonia [9%], and wasting syndrome [8%]). The incidence of peripheral neuropathy rose significantly with the number of drugs comprising treatment regimens (> or = 4 vs 1-3; P = .013) and tended to be higher in patients with longer exposure to stavudine (29% with > or = 24 months' exposure vs 13% with < 24 months). Because peripheral neuropathy was observed with such high frequency, vigilance for signs and symptoms of this condition appears warranted if stavudine-containing regimens are to be continued. [ABSTRACT FROM AUTHOR]

Patient autonomy and informed consent are cornerstones of medicine, though often clinicians interact directly with surrogate decision makers (SDMs) instead of patients when the latter is deemed incapacitated. Although most SDMs are able to fulfill their duty as proxies, incongruence between SDM role and behavior may occur, even after the best mediation efforts possible by various clinical teams. Instances in which SDMs act inappropriately in their role and fail to respond to such efforts by clinical teams warrant serious consideration of SDM replacement. We offer a case series of such instances, describe difficulties faced by SDMs in their role, and offer ethical and legal perspective regarding the challenging and removal of SDMs after thoughtful and collective deliberation. [ABSTRACT FROM AUTHOR]

A multistructural object-based LiDAR approach to predict plant richness in complex structure forests is presented. A normalized LiDAR point cloud was split into four height ranges: 1) high canopies (points above 16 m); 2) middle-high canopies (8–16 m); 3) middle-low canopies (2–8 m); and 4) low canopies (0–2 m). A digital canopy model (DCM) was obtained from the full normalized LiDAR point cloud, and four pseudo-DCMs (pDCMs) were obtained from the split point clouds. We applied a multiresolution segmentation algorithm to the DCM and the four pDCMs to obtain crown objects. A partial least squares path model (PLS-PM) algorithm was applied to predict total vascular plant richness using object-based image analysis (OBIA) variables, derived from the delineated crown objects, and topographic variables, derived from a digital terrain model. Results showed that the object-based model was able to predict the total richness with an \mathrmr^2 of 0.64 and a root-mean-square error of four species. Topographic variables showed to be more important than the OBIA variables to predict richness. Furthermore, high-medium canopies (8–16 m) showed the biggest correlation with the total plant richness within the structural segments of the forest. [ABSTRACT FROM PUBLISHER]

A microelectromechanical-systems-based calorimeter designed for use on a synchrotron nano-focused X-ray beamline is described. This instrument allows quantitative DC and AC calorimetric measurements over a broad range of heating/cooling rates (≤100000 K s-1) and temperature modulation frequencies (≤1 kHz). The calorimeter was used for high-resolution thermal imaging of nanogram-sized samples subjected to X-ray-induced heating. For a 46 ng indium particle, the measured temperature rise reaches ~0.2 K, and is directly correlated to the X-ray absorption. Thermal imaging can be useful for studies of heterogeneous materials exhibiting physical and/or chemical transformations. Moreover, the technique can be extended to three-dimensional thermal nanotomography. [ABSTRACT FROM AUTHOR]

Radial symmetry is essential for the conventional view of the polymer spherulite microstructure. Typically it is assumed that, in the course of the spherulite morphogenesis, the lamellar crystals grow radially. Using submicron X-ray diffraction, it is shown that in banded spherulites of poly(propylene adipate) the crystals have the shape of a helix with flat-on crystals winding around a virtual cylinder of about 6 µm in diameter. The helix angle of 30° implies that the crystal growth direction is tilted away from the spherulite radius by this angle. The implications of the helical crystal shape contradict the paradigm of the spherulitic microstructure. The radial growth rate of such spherulites does not correspond to the crystal growth rate, but to the propagation rate of the virtual cylinder the ribbons wind around. [ABSTRACT FROM AUTHOR]

A novel wedge-shaped compound containing two diacetylene tails, namely, methyl 3,5-bis(trideca-2,4-diyn-1yloxyl)benzoate (DDABM), was synthesized. As shown by UV/Vis spectroscopy this compound can be polymerized under UV irradiation. The crystalline structure of DDABM was investigated by grazing-incidence wide-angle X-ray diffraction on oriented crystalline films deposited on PTFE-rubbed silicon wafer substrates. Furthermore, the spherulites formed in thicker films were analyzed by wide-angle X-ray diffraction. A molecular packing model of DDABM based on the X-ray diffraction data is proposed. The diacetylene units are oriented along a defined lattice direction with a reticular distance of 4.85 Å, which fulfills the requirements for topochemical polymerization. It was observed that UV polymerization does not affect the phase behavior of the compound, but mainly alters its optical properties. [ABSTRACT FROM AUTHOR]

Peramivir, an intravenously administered neuraminidase inhibitor, may be used concomitantly with other influenza antivirals. Two studies were conducted to assess the potential for pharmacokinetic interactions of peramivir when coadministered with oseltamivir or rimantadine. Twenty-one healthy subjects were enrolled in each randomized, open-label, crossover study, and they received 1 intravenous dose of peramivir (600 mg), 1 oral dose of oseltamivir (75 mg) or rimantadine (100 mg), or a combination of peramivir with oseltamivir or rimantadine. Assessment of the 90% confidence interval for the geometric mean ratio of peramivir and oseltamivir carboxylate or rimantadine pharmacokinetic parameters showed no effect of oseltamivir or rimantadine on the pharmacokinetics of peramivir and no effect of peramivir on the pharmacokinetics of oseltamivir carboxylate or rimantadine. The drugs were well tolerated. These results suggest no reason to expect an effect of concomitant administration of oseltamivir or rimantadine on the safety profile of peramivir in patients with influenza. [ABSTRACT FROM PUBLISHER]

Peramivir, an investigational intravenous neuraminidase inhibitor, was given to 31 hospitalized patients with severe viral pneumonia during the 2009 H1N1 influenza pandemic under the Emergency IND regulations. The drug was generally well tolerated and associated with recovery in most patientes.(See the editorial commentary by Jain et al, on pages 707–709.)Background. Peramivir, an investigational intravenous neuraminidase inhibitor in Phase 3 trials for hospitalized patients, was made available during the 2009 H1N1 influenza pandemic under the Emergency Investigational New Drug (eIND) regulations. We describe the clinical characteristics and outcomes of all patients for whom peramivir was requested under the eIND.Methods. After obtaining eIND approval from the Food and Drug Administration and local institutional review board approval, clinicians caring for hospitalized patients with influenza administered intravenous peramivir and collected information on demographic characteristics, clinical characteristics, and outcomes.Results. From April through October 2009, peramivir was requested for 42 patients and administered to 20 adults and 11 children. At hospitalization, all patients had rapidly progressing, radiographically confirmed viral pneumonia with respiratory failure, and all but 1 patient required mechanical ventilation. In most patients, including 1 person with documented oseltamivir-resistant infection, the illness had progressed despite oseltamivir treatment. Peramivir was administered for 1–14 days (median duration, 10 days). The 14-day, 28-day, and 56-day survival rates were 76.7%, 66.7%, and 59.0%, respectively. Peramivir was generally well tolerated.Conclusions. Intravenous peramivir was well tolerated and was associated with recovery in most patients hospitalized with severe 2009 H1N1 influenza viral pneumonia and treated under an eIND. [ABSTRACT FROM AUTHOR]

Purpose – Informal settlements are consistent areas in Latin America which exhibit distinctive urban and social dynamics. However, despite their size and impact, these settlements have been traditionally overlooked in terms of the contribution that they make to the city and to any place branding strategy. These areas are commonly seen as having nothing more to offer than poverty and constraint. However, literature and research shows their possibilities beyond those traditional limits, and arguably they can actively contribute to branding cities in Latin America. The purpose of this paper is to critically explore the contribution that informal settlements can make to a fairer, more real and authentic branding of cities. Design/methodology/approach – The discussion is based on two ongoing research projects, one in urban planning and the other one in business, together with a first-hand knowledge and engagement with informal settlements in Bogotá. Findings – Informal settlements can contribute positively to branding cities. Trying to "hide" these areas from visitors' views is not only impossible because of their size, but also not desirable because of how they can enrich a branding strategy. However, there are also major downsides which need to be taken into consideration. Originality/value – The value resides in the attempt to link two themes that traditionally have been nearly opposite (informal settlements and branding cities), and the elaboration on the outcome of this relationship. [ABSTRACT FROM AUTHOR]

Objectives. Long-haul truck drivers and their commercial sex contacts (CCs) have been associated with the spread of sexually transmitted infections (STIs) in the developing world. However, there is a paucity of information about the STI risk behaviors of these populations in the U.S. We conducted a qualitative phase of a two-phase study to gather information about STI-related risk behaviors in drivers and their CCs in New Mexico. Methods. Between July and September 2004, we conducted face-to-face unstructured and semistructured qualitative interviews at trucking venues, health department facilities, and a community-based organization to solicit information on sexual behavior and condom and illicit drug use. The interviews were audiotaped, transcribed, reviewed for quality control, and then coded and analyzed for emerging themes using NVivo® software. Results. Thirty-three long-haul truck drivers and 15 CCs completed the interview. The truck drivers were mostly male and non-Hispanic white with a mean age of 41 years. The majority of the CCs were female, the largest percentage was Hispanic, and the mean age was 36 years. Data suggested risky sexual behavior and drug use (i.e., inconsistent condom use, illicit drug use including intravenous drug use, and the exchange of sex for drugs) that could facilitate STI/human immunodeficiency virus (HIV) and hepatitis virus transmission. Results also showed a low knowledge about STIs and lack of access to general health care for both populations. Conclusions. Additional studies are needed to further assess risk and inform the development of prevention interventions and methods to provide STI/HIV and other medical services to these populations. [ABSTRACT FROM AUTHOR]

Objectives. We examined sexually transmitted infection (STI), HIV, and hepatitis virus prevalence and risk behaviors among truck drivers. Methods. We asked participants about their risk behaviors, and we screened them for STIs, HIV, and hepatitis infections. We used logistic regression to identify factors associated with outcomes. Results. Of the 652 enrolled participants, 21% reported sex with sex workers or casual partners in the prior year. Driving solo (odds ratio [OR]=15.04; 95% confidence interval [CI]=1.92, 117.53; P=.01), history of injection drug use (IDU; OR=2.69; 95% CI=1.19, 6.12; P=.02), and history of an STI (OR=2.47; 95% CI=1.19, 5.09; P=.01) were independently associated with high-risk sexual behaviors. Fourteen percent of participants reported drug use in the previous year, and 11% reported having ever injected drugs. Participants tested positive as follows: 54 for HCV antibodies (8.5%), 66 for hepatitis B anticore (anti-HBc) antibodies (10.4%), 8 for chlamydia (1.3%), 1 for gonorrhea (0.2%), 1 for syphilis (0.2%), and 1 for HIV (0.2%). History of injecting drugs (OR=26.91; 95% CI=11.61, 62.39; P<.01) and history of anti-HBc antibodies (OR=7.89; 95% CI=3.16, 19.68; P<.01) were associated with HCV infection. Conclusions. Our results suggest a need for hepatitis C screening and STI risk-reduction interventions in this population. [ABSTRACT FROM AUTHOR]

While African Americans in the United States are disproportionately affected by HIV, they are less likely to take antiretroviral therapies. Different first-line antiretroviral therapies are associated with short-term and long-term adverse event (AE) risks. We estimated the willingness of antiretroviral-naïve, HIV-positive African Americans to accept risks of acute AEs with known outcomes and long-term AEs with uncertain outcomes in exchange for virologic suppression. We estimated the relative importance of short-term and long-term AE risks. Two hundred thirty-five subjects were recruited through eight clinics in the United States. One hundred fifty-eight subjects met study inclusion criteria. One hundred fifty-three subjects completed a series of choice-format conjoint trade-off tasks. In each task, subjects were asked to choose between two hypothetical treatments with varying levels of virologic failure, risks of hypersensitivity reaction, decreases in bone mineral density (BMD), and renal impairment, and outcome uncertainty associated with the risks of decreased BMD and renal impairment. Attributes were expressed as probabilities of occurrence. We calculated the relative importance of each AE and the level of risk subjects would accept to reduce the risk of virologic failure. Subjects indicated that short-term AEs with relatively certain outcomes are preferred to long-term AEs with uncertain outcomes. Subjects were strongly averse to the risk of decreased BMD that could not be treated successfully or when the outcome was uncertain and to the risk of renal impairment that could not be treated successfully. Subjects were willing to accept increased risks of AEs in exchange for lower risk of virologic failure. [ABSTRACT FROM AUTHOR]

Background: Numerous large, long-term clinical trials have assessed the safety and efficacy of the two antiretroviral nucleoside analogs lamivudine and abacavir as components of highly active antiretroviral therapy for the treatment of patients with HIV-1 infection. This analysis pools the safety data on multi-drug regimens containing lamivudine/abacavir in combination with a protease inhibitor, non-nucleoside reverse transcriptase inhibitor, or nucleoside reverse transcriptase inhibitor.Methods: Data are presented from 2279 treatment-naive HIV-1-infected patients who were enrolled in one of five clinical trials that assessed the safety and tolerability of lamivudine/abacavir in combination with a third antiretroviral agent. The well characterised combination of lamivudine/zidovudine plus efavirenz was used as the comparator arm. All available safety data (including data beyond 48 weeks) were used in all analyses, which included calculation of treatment emergent laboratory values, adverse events (AEs), serious AEs, fatalities, drug discontinuations and any summaries by study week of safety data.Results: In the total lamivudine/abacavir group, 1585 of 2229 (71%) patients experienced at least one drug-related AE during the study compared with 247 of 325 (76%) patients in the lamivudine/zidovudine/efavirenz treatment group. The most common drug-related AEs reported during the study were diarrhoea (19%), nausea (18%) and dizziness (12%) in patients treated with lamivudine/abacavir plus a third agent, and nausea (31%), dizziness (27%) and headache (16%) in the comparator group. Overall, in the total lamivudine/abacavir group there were only three severe (Division of AIDS 1992 toxicity table grade 3 or 4) AEs that were reported in >1% of subjects: drug hypersensitivity, elevated ALT levels and elevated AST levels. In the lamivudine/zidovudine/efavirenz group, six severe AEs that occurred in >1% of the safety population were reported. The abacavir hypersensitivity reaction rate reported in these five studies was comparable with the previously reported rate. In addition, there were no patient fatalities attributed by investigators to the study drugs.Conclusion: This analysis indicates that the combination of lamivudine/abacavir is generally safe for the majority of patients when used as part of combination therapy. [ABSTRACT FROM AUTHOR]

Background: Hydroxyurea (HU) is an immunomodulatory agent that has been documented to enhance the antiretroviral activity of nucleoside reverse transcriptase inhibitors, such as abacavir (ABC) and didanosine (ddI), and would be expected to improve virologic efficacy. Methods: A 48-week, phase IV, multicenter, open-label, proof-of-concept clinical trial was conducted to evaluate second-line, protease inhibitor (PI)-sparing therapy with ABC/efavirenz (EFV)/ddI plus HU or without HU in HIV-infected subjects failing to achieve HIV-1 RNA ≤ 400 copies/mL after ≥ 16 weeks of treatment with lamivudine/zidovudine or lamivudine/stavudine, plus 1 or 2 PIs. Subjects were assigned to ABC (300 mg twice daily)/ EFV (600 mg once daily)/ ddI (400 mg once daily) plus HU (500 mg twice daily) (n = 30) or this regimen without HU (n = 24). Results: Baseline mean HIV-1 RNA was 3.86 log10 copies/mL and CD4+ cell count was 345 cells/ mm3. A similar percentage of subjects in the non-HU arm (58%) and HU arm (53%) complete the study. Intent-to-treat: missing = failure analysis showed no differences in proportions of subjects in the non-HU and HU arms achieving undetectable plasma HIV-1 RNA levels at week 24 (<400 copies/mL: 58% [14/24] vs 57% [17/30], P = 0.899; <50 copies/mL (50% [12/24] vs 47% [14/30], P = 0.780). Median change from baseline in CD4+ cell count in the non-HU and HU arms at week 48 was +114 cells/mm3 and -63 cells/mm3 (P = 0.007), respectively. Both regimens were generally well tolerated, although more subjects in the HU arm withdrew prematurely from the study due to adverse events (23% vs 4%). Four cases of possible ABC-related hypersensitivity were observed. Conclusion: ABC/EFV/ddI was an effective and well-tolerated second-line regimen for nucleoside/ PI-experienced HIV-infected subjects. The addition of HU blunted the CD4+ cell response, did not appear to enhance antiviral activity, and resulted in more treatment-limiting adverse events. [ABSTRACT FROM AUTHOR]

Background: Hyperlipidemia secondary to protease inhibitors (PI) may abate by switching to anti-HIV medications without lipid effects. Method: An open-label, randomized pilot study compared changes in fasting lipids and HIV-1 RNA in 104 HIV-infected adults with PI-associated hyperlipidemia (fasting serum total cholesterol > 200 mg/dL) who were randomized either to a regimen in which their PI was replaced by abacavir 300 mg twice daily (n = 52) or a regimen in which their PI was continued (n = 52) for 28 weeks. All patients had undetectable viral loads (HIV-1 RNA <50 copies/mL) at baseline and were naive to abacavir and non-nucleoside reverse transcriptase inhibitors. Results: At baseline, the mean total cholesterol was 243 mg/dL, low density lipoprotein (LDL)-cholesterol 149 mg/dL, high density lipoprotein (HDL)-cholesterol 41 mg/dL, and triglycerides 310 mg/dL. Mean CD4+ cell counts were 551 and 531 cells/mm3 in the abacavir-switch and PIcontinuation arms, respectively. At week 28, the abacavir-switch arm had significantly greater least square mean reduction from baseline in total cholesterol (-42 vs -10 mg/dL, P < 0.001), LDLcholesterol (-14 vs +5 mg/dL, P = 0.016), and triglycerides (-134 vs -36 mg/dL, P = 0.019) than the PI-continuation arm, with no differences in HDL-cholesterol (+0.2 vs +1.3 mg/dL, P = 0.583). A higher proportion of patients in the abacavir-switch arm had decreases in protocol-defined total cholesterol and triglyceride toxicity grades, whereas a smaller proportion had increases in these toxicity grades. At week 28, an intent-to treat: missing = failure analysis showed that the abacavirswitch and PI-continuation arms did not differ significantly with respect to proportion of patients maintaining HIV-1 RNA <400 or <50 copies/mL or adjusted mean change from baseline in CD4+ cell count. Two possible abacavir-related hypersensitivity reactions were reported. No significant changes in glucose, insulin, insulin resistance, C-peptide, or waist-to-hip ratios were observed in either treatment arm, nor were differences in these parameters noted between treatments. Conclusion: In hyperlipidemic, antiretroviral-experienced patients with HIV-1 RNA levels <50 copies/mL and CD4+ cell counts <500 cells/mm3, substituting abacavir for hyperlipidemiaassociated PIs in combination antiretroviral regimens improves lipid profiles and maintains virologic suppression over a 28-week period, and it simplifies treatment. [ABSTRACT FROM AUTHOR]