Optical trapping has been implemented in many areas of physics and biology as a noncontact sample manipulation technique to study the structure and dynamics of nano- and mesoscale objects. It provides a unique approach for manipulating microscopic objects without inducing undesired changes in structure. Combining optical trapping with hard X-ray microscopy techniques, such as coherent diffraction imaging and crystallography, provides a nonperturbing environment where electronic and structural dynamics of an individual particle in solution can be followed in situ.
View Article and Find Full Text PDFJ Laryngol Otol
December 2018
Objective: This study aimed to estimate the cost-effectiveness of Coblation compared with cold steel tonsillectomy in adult and paediatric patients in the UK.
Method: Decision analysis was undertaken by combining published clinical outcomes with resource utilisation estimates derived from a panel of clinicians.
Results: Using a cold steel procedure instead of Coblation is expected to generate an incremental cost of more than £2000 for each additional avoided haemorrhage, and the probability of cold steel being cost-effective was approximately 0.
The development of a prophylactic vaccine for hepatitis C virus (HCV) remains a global health challenge. Cumulative evidence supports the importance of antibodies targeting the HCV E2 envelope glycoprotein to facilitate viral clearance. However, a significant challenge for a B cell-based vaccine is focusing the immune response on conserved E2 epitopes capable of eliciting neutralizing antibodies not associated with viral escape.
View Article and Find Full Text PDFObjective: To evaluate the patient pathways and associated health outcomes, resource use and corresponding costs attributable to managing unhealed surgical wounds in clinical practice, from initial presentation in the community in the UK.
Methods: This was a retrospective cohort analysis of the records of 707 patients in The Health Improvement Network (THIN) database whose wound failed to heal within 4 weeks of their surgery. Patients' characteristics, wound-related health outcomes and healthcare resource use were quantified, and the total National Health Service (NHS) cost of patient management was estimated at 2015/2016 prices.
The capacity of microalgae to advance the limit of technology of nutrient recovery and accumulate storage carbon make them promising candidates for wastewater treatment. However, the extent to which these capabilities are influenced by microbial community composition remains poorly understood. To address this knowledge gap, 3 mixed phototrophic communities sourced from distinct latitudes within the continental United States (28° N, Tampa, FL; 36° N, Durham, NC; and 40° N, Urbana, IL) were operated in sequencing batch reactors (8 day solids residence time, SRT) subjected to identical diel light cycles with media addition at the start of the nighttime period.
View Article and Find Full Text PDFBackground: An increasing number of HIV-positive individuals now start antiretroviral therapy (ART) with high CD4 cell counts. We investigated whether this makes restoration of CD4 and CD8 cell counts and the CD4:CD8 ratio during virologically suppressive ART to median levels seen in HIV-uninfected individuals more likely and whether restoration depends on gender, age, and other individual characteristics.
Methods: We determined median and quartile reference values for CD4 and CD8 cell counts and their ratio using cross-sectional data from 2309 HIV-negative individuals.
Zika virus (ZIKV) is a mosquito-borne positive-sense single-stranded RNA virus in the family of Flaviviridae. Unlike other flaviviruses, ZIKV infection of pregnant women may result in birth defects in their newborns, such as microcephaly or vision problem. ZIKV is known to antagonize the interferon (IFN) production in infected cells.
View Article and Find Full Text PDFSuspended growth, mixed community phototrophic wastewater treatment systems (including high-rate algal ponds and photobioreactors) have the potential to achieve biological nitrogen and phosphorus recovery with effluent nutrient concentrations below the current limit-of-technology. In order to achieve reliable and predictive performance, it is necessary to establish a thorough understanding of how design and operational decisions influence the complex community structure governing nutrient recovery in these systems. Solids residence time (SRT), a critical operational parameter governing growth rate, was leveraged as a selective pressure to shape microbial community structure in laboratory-scale photobioreactors fed secondary effluent from a local wastewater treatment plant.
View Article and Find Full Text PDFEnviron Sci Technol
November 2018
Modeling efforts to understand the financial implications of microalgal biofuels often assume a static basis for microalgae biomass composition and cost, which has constrained cultivation and downstream conversion process design and limited in-depth understanding of their interdependencies. For this work, a dynamic biological cultivation model was integrated with thermo-chemical/biological unit process models for downstream biorefineries to increase modeling fidelity, to provide mechanistic links among unit operations, and to quantify minimum product selling prices of biofuels via techno-economic analysis. Variability in design, cultivation, and conversion parameters were characterized through Monte Carlo simulation, and sensitivity analyses were conducted to identify key cost and fuel yield drivers.
View Article and Find Full Text PDFPhys Chem Chem Phys
November 2018
Cuprous oxide (Cu2O) is a promising catalyst for several important reactions. However, the atomic structures of defective Cu2O surfaces, which critically affect the catalytic properties both thermodynamically and kinetically, are not unambiguously characterized. High-resolution scanning tunneling microscopy (STM), combined with density functional theory (DFT) calculations and STM simulations, has been used to determine the atomic structure of the (111) surface of a Cu2O bulk crystal.
View Article and Find Full Text PDFAdherence to antiretroviral therapy (ART) is critical for successful treatment of Human Immunodeficiency Virus (HIV), but comparisons across settings are difficult because adherence is measured in different ways. We examined utility of different adherence measures for identification of patients at risk of viral failure (VF). Eight cohorts in the ART Cohort Collaboration contributed data from pharmacy refills or self-report questionnaires collected between 1996 and 2013 ( = 11689).
View Article and Find Full Text PDFNeuroimaging facilitates the translation of animal pre-clinical research to human application. The large porcine spinal cord is useful for testing invasive interventions. Ideally, the safety and efficacy of a delayed intervention is tested in pigs that have recovered sufficiently after spinal cord injury (SCI) to allow either deterioration or improvement of function to be detected.
View Article and Find Full Text PDFThe objective of this paper is to unveil a novel damping mechanism exhibited by 3D woven lattice materials (3DW), with emphasis on response to high-frequency excitations. Conventional bulk damping materials, such as rubber, exhibit relatively low stiffness, while stiff metals and ceramics typically have negligible damping. Here we demonstrate that high damping and structural stiffness can be simultaneously achieved in 3D woven lattice materials by brazing only select lattice joints, resulting in a load-bearing lattice frame intertwined with free, 'floating' lattice members to generate damping.
View Article and Find Full Text PDFSevere spinal cord injury leads to hemorrhage, edema and elevated tissue pressures that propagate ischemia. Liquefactive necrosis of damaged tissue eventually results in chronic cavities due to a wound healing process lacking adhesive contractile cells. Biomaterials can potently influence wound healing responses.
View Article and Find Full Text PDFGenerating and amplifying light in silicon (Si) continues to attract significant attention due to the possibility of integrating optical and electronic components in a single material platform. Unfortunately, silicon is an indirect band gap material and therefore an inefficient emitter of light. With the rise of integrated photonics, the search for silicon-based light sources has evolved from a scientific quest to a major technological bottleneck for scalable, CMOS-compatible, light sources.
View Article and Find Full Text PDFAntimicrob Agents Chemother
November 2018
Fungal endophthalmitis remains a significant cause of vision impairment and blindness. Moreover, the prognosis is poor, in part due to delay in diagnosis and to limited availability of effective antifungal agents with good ocular penetration. Thus, it is imperative to evaluate the therapeutic efficacy in fungal endophthalmitis of newer antifungal agents.
View Article and Find Full Text PDFBackground: Immature neurons can extend processes after transplantation in adult animals. Neuronal relays can form between injected neural stem cells (NSCs) and surviving neurons, possibly improving recovery after spinal cord injury (SCI). Cell delivery methods of single or multiple bolus injections of concentrated cell suspensions thus far tested in preclinical and clinical experiments are suboptimal for new tract formation.
View Article and Find Full Text PDFObjectives: The aim of this study was to estimate the patterns of care and annual levels of healthcare resource use attributable to managing pressure ulcers (PUs) in clinical practice in the community by the UK's National Health Service (NHS), and the associated costs of patient management.
Methods: This was a retrospective cohort analysis of the records of 209 patients identified within a randomly selected population of 6000 patients with any type of wound obtained from The Health Improvement Network (THIN) Database, who developed a PU in the community and excluded hospital-acquired PUs. Patients' characteristics, wound-related health outcomes and healthcare resource use were quantified over 12 months from initial presentation, and the corresponding total NHS cost of patient management was estimated at 2015/2016 prices.
Purpose: Pre-exposure prophylaxis (PrEP) with oral emtricitibine/tenofovir disoproxil fumarate (TDF/FTC) reduces the risk of HIV infection by >90% when taken as prescribed. Trends in prevalence of PrEP use, which account for persons who have stopped PrEP, increased through 2016, but have not been described since.
Methods: Annual prevalence estimates of unique, TDF/FTC PrEP users (individuals with ≥1 day of a filled PrEP prescription in a given year) in the United States (US) were generated for 2012-2017 from a national prescription database.
Background: Few HIV interventions have demonstrated efficacy in reducing HIV risk among adolescent men who have sex with men (AMSM), and fewer still have recognized the unique needs of AMSM based on race/ethnicity or geographical setting. Recognizing that youths' HIV vulnerability is intricately tied to their development and social context, delivering life skills training during adolescence might delay the onset or reduce the consequences of risk factors for HIV acquisition and equip AMSM with the skills to navigate HIV prevention. This protocol describes the development and testing of iREACH, an online multilevel life skills intervention for AMSM.
View Article and Find Full Text PDFPurpose: The number of individuals who have started a regimen for HIV pre-exposure prophylaxis (PrEP) in the United States is not well characterized but has been on the rise since 2012. This analysis assesses the distribution of PrEP use nationally and among subgroups.
Methods: A validated algorithm quantifying tenofovir disoproxil fumarate/emtricitabine for PrEP in the United States was applied to a national prescription database to determine the quarterly prevalence of PrEP use.
Hepatitis C virus (HCV) is a major global health concern, and though therapeutic options have improved, no vaccine is available despite decades of research. As HCV can rapidly mutate to evade the immune response, an effective HCV vaccine must rely on identification and characterization of sites critical for broad immune protection and viral neutralization. This knowledge depends on structural and mechanistic insights of the E1 and E2 envelope glycoproteins, which assemble as a heterodimer on the surface of the virion, engage coreceptors during host cell entry, and are the primary targets of antibodies.
View Article and Find Full Text PDFHigh-level quadriplegia is a devastating condition with limited treatment options. Bone marrow derived stem cells (BMSCs) are reported to have immunomodulatory and neurotrophic effects in spinal cord injury (SCI). We report a subject with complete C2 SCI who received three anatomically targeted intrathecal infusions of BMSCs under a single-patient expanded access investigational new drug (IND).
View Article and Find Full Text PDFDespite the great promise of armchair graphene nanoribbons (aGNRs) as high-performance semiconductors, practical band-gap engineering of aGNRs remains an unmet challenge. Given that width and edge structures are the two key factors for modulating band-gaps of aGNRs, a reliable synthetic method that allows control of both factors would be highly desirable. Here we report a simple modular strategy for efficient preparation of N = 6 aGNR, the narrowest member in the N = 3p (p: natural number) aGNR family, and two unsymmetrically edge-functionalized GNRs that contain benzothiadiazole and benzotriazole moieties.
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