Showing papers by "University of Central Florida published in 2014"

The FNIH Sarcopenia Project: Rationale, Study Description, Conference Recommendations, and Final Estimates

Abstract: Background. Low muscle mass and weakness are common and potentially disabling in older adults, but in order to become recognized as a clinical condition, criteria for diagnosis should be based on clinically relevant thresholds and independently validated. The Foundation for the National Institutes of Health Biomarkers Consortium Sarcopenia Project used an evidence-based approach to develop these criteria. Initial findings were presented at a conference in May 2012, which generated recommendations that guided additional analyses to determine final recommended criteria. Details of the Project and its findings are presented in four accompanying manuscripts.

Prevalence of and interventions for sarcopenia in ageing adults: a systematic review. Report of the International Sarcopenia Initiative (EWGSOP and IWGS)

Abstract: OBJECTIVE: to examine the clinical evidence reporting the prevalence of sarcopenia and the effect of nutrition and exercise interventions from studies using the consensus definition of sarcopenia proposed by the European Working Group on Sarcopenia in Older People (EWGSOP).METHODS: PubMed and Dialog databases were searched (January 2000-October 2013) using pre-defined search terms. Prevalence studies and intervention studies investigating muscle mass plus strength or function outcome measures using the EWGSOP definition of sarcopenia, in well-defined populations of adults aged ≥50 years were selected.RESULTS: prevalence of sarcopenia was, with regional and age-related variations, 1-29% in community-dwelling populations, 14-33% in long-term care populations and 10% in the only acute hospital-care population examined. Moderate quality evidence suggests that exercise interventions improve muscle strength and physical performance. The results of nutrition interventions are equivocal due to the low number of studies and heterogeneous study design. Essential amino acid (EAA) supplements, including ∼2.5 g of leucine, and β-hydroxy β-methylbutyric acid (HMB) supplements, show some effects in improving muscle mass and function parameters. Protein supplements have not shown consistent benefits on muscle mass and function.CONCLUSION: prevalence of sarcopenia is substantial in most geriatric settings. Well-designed, standardised studies evaluating exercise or nutrition interventions are needed before treatment guidelines can be developed. Physicians should screen for sarcopenia in both community and geriatric settings, with diagnosis based on muscle mass and function. Supervised resistance exercise is recommended for individuals with sarcopenia. EAA (with leucine) and HMB may improve muscle outcomes.

Parity-time–symmetric microring lasers

Abstract: The ability to control the modes oscillating within a laser resonator is of fundamental importance. In general, the presence of competing modes can be detrimental to beam quality and spectral purity, thus leading to spatial as well as temporal fluctuations in the emitted radiation. We show that by harnessing notions from parity-time (PT) symmetry, stable single–longitudinal mode operation can be readily achieved in a system of coupled microring lasers. The selective breaking of PT symmetry can be used to systematically enhance the maximum attainable output power in the desired mode. This versatile concept is inherently self-adapting and facilitates mode selectivity over a broad bandwidth without the need for other additional intricate components. Our experimental findings provide the possibility to develop synthetic optical devices and structures with enhanced functionality.

Particle Size Effects in the Catalytic Electroreduction of CO2 on Cu Nanoparticles

Abstract: A study of particle size effects during the catalytic CO2 electroreduction on size-controlled Cu nanoparticles (NPs) is presented. Cu NP catalysts in the 2–15 nm mean size range were prepared, and their catalytic activity and selectivity during CO2 electroreduction were analyzed and compared to a bulk Cu electrode. A dramatic increase in the catalytic activity and selectivity for H2 and CO was observed with decreasing Cu particle size, in particular, for NPs below 5 nm. Hydrocarbon (methane and ethylene) selectivity was increasingly suppressed for nanoscale Cu surfaces. The size dependence of the surface atomic coordination of model spherical Cu particles was used to rationalize the experimental results. Changes in the population of low-coordinated surface sites and their stronger chemisorption were linked to surging H2 and CO selectivities, higher catalytic activity, and smaller hydrocarbon selectivity. The presented activity–selectivity–size relations provide novel insights in the CO2 electroreduction r...

Diversity of ageing across the tree of life

Abstract: Evolution drives, and is driven by, demography. A genotype moulds its phenotype’s age patterns of mortality and fertility in an environment; these two patterns in turn determine the genotype’s fitness in that environment. Hence, to understand the evolution of ageing, age patterns of mortality and reproduction need to be compared for species across the tree of life. However, few studies have done so and only for a limited range of taxa. Here we contrast standardized patterns over age for 11 mammals, 12 other vertebrates, 10 invertebrates, 12 vascular plants and a green alga. Although it has been predicted that evolution should inevitably lead to increasing mortality and declining fertility with age after maturity, there is great variation among these species, including increasing, constant, decreasing, humped and bowed trajectories for both long- and short-lived species. This diversity challenges theoreticians to develop broader perspectives on the evolution of ageing and empiricists to study the demography of more species.

Space-division multiplexing: the next frontier in optical communication

Abstract: Space-division multiplexing (SDM) uses multiplicity of space channels to increase capacity for optical communication. It is applicable for optical communication in both free space and guided waves. This paper focuses on SDM for fiber-optic communication using few-mode fibers or multimode fibers, in particular on the critical challenge of mode crosstalk. Multiple-input–multiple-output (MIMO) equalization methods developed for wireless communication can be applied as an electronic method to equalize mode crosstalk. Optical approaches, including differential modal group delay management, strong mode coupling, and multicore fibers, are necessary to bring the computational complexity for MIMO mode crosstalk equalization to practical levels. Progress in passive devices, such as (de)multiplexers, and active devices, such as amplifiers and switches, which are considered straightforward challenges in comparison with mode crosstalk, are reviewed. Finally, we present the prospects for SDM in optical transmission and networking.

Exceptional size-dependent activity enhancement in the electroreduction of CO2 over Au nanoparticles.

Abstract: The electrocatalytic reduction of CO2 to industrial chemicals and fuels is a promising pathway to sustainable electrical energy storage and to an artificial carbon cycle, but it is currently hindered by the low energy efficiency and low activity displayed by traditional electrode materials. We report here the size-dependent catalytic activity of micelle-synthesized Au nanoparticles (NPs) in the size range of ∼1–8 nm for the electroreduction of CO2 to CO in 0.1 M KHCO3. A drastic increase in current density was observed with decreasing NP size, along with a decrease in Faradaic selectivity toward CO. Density functional theory calculations showed that these trends are related to the increase in the number of low-coordinated sites on small NPs, which favor the evolution of H2 over CO2 reduction to CO. We show here that the H2/CO product ratio can be specifically tailored for different industrial processes by tuning the size of the catalyst particles.

Planck 2013 results. XXIX. The Planck catalogue of Sunyaev-Zeldovich sources

Abstract: We describe the all-sky Planck catalogue of clusters and cluster candidates derived from Sunyaev-Zeldovich (SZ) effect detections using the first 15.5 months of Planck satellite observations. The catalogue contains 1227 entries, making it over six times the size of the Planck Early SZ (ESZ) sample and the largest SZ-selected catalogue to date. It contains 861 confirmed clusters, of which 178 have been confirmed as clusters, mostly through follow-up observations, and a further 683 are previously-known clusters. The remaining 366 have the status of cluster candidates, and we divide them into three classes according to the quality of evidence that they are likely to be true clusters. The Planck SZ catalogue is the deepest all-sky cluster catalogue, with redshifts up to about one, and spans the broadest cluster mass range from (0.1 to 1.6) x 10(15) M-circle dot. Confirmation of cluster candidates through comparison with existing surveys or cluster catalogues is extensively described, as is the statistical characterization of the catalogue in terms of completeness and statistical reliability. The outputs of the validation process are provided as additional information. This gives, in particular, an ensemble of 813 cluster redshifts, and for all these Planck clusters we also include a mass estimated from a newly-proposed SZ-mass proxy. A refined measure of the SZ Compton parameter for the clusters with X-ray counter-parts is provided, as is an X-ray flux for all the Planck clusters not previously detected in X-ray surveys.

Behavior Change Techniques Implemented in Electronic Lifestyle Activity Monitors: A Systematic Content Analysis

Abstract: Background: Electronic activity monitors (such as those manufactured by Fitbit, Jawbone, and Nike) improve on standard pedometers by providing automated feedback and interactive behavior change tools via mobile device or personal computer. These monitors are commercially popular and show promise for use in public health interventions. However, little is known about the content of their feedback applications and how individual monitors may differ from one another. Objective: The purpose of this study was to describe the behavior change techniques implemented in commercially available electronic activity monitors. Methods: Electronic activity monitors (N=13) were systematically identified and tested by 3 trained coders for at least 1 week each. All monitors measured lifestyle physical activity and provided feedback via an app (computer or mobile). Coding was based on a hierarchical list of 93 behavior change techniques. Further coding of potentially effective techniques and adherence to theory-based recommendations were based on findings from meta-analyses and meta-regressions in the research literature. Results: All monitors provided tools for self-monitoring, feedback, and environmental change by definition. The next most prevalent techniques (13 out of 13 monitors) were goal-setting and emphasizing discrepancy between current and goal behavior. Review of behavioral goals, social support, social comparison, prompts/cues, rewards, and a focus on past success were found in more than half of the systems. The monitors included a range of 5-10 of 14 total techniques identified from the research literature as potentially effective. Most of the monitors included goal-setting, self-monitoring, and feedback content that closely matched recommendations from social cognitive theory. Conclusions: Electronic activity monitors contain a wide range of behavior change techniques typically used in clinical behavioral interventions. Thus, the monitors may represent a medium by which these interventions could be translated for widespread use. This technology has broad applications for use in clinical, public health, and rehabilitation settings. [J Med Internet Res 2014;16(8):e192]

Ultra-high-density spatial division multiplexing with a few-mode multicore fibre

Abstract: Single-mode fibres with low loss and a large transmission bandwidth are a key enabler for long-haul high-speed optical communication and form the backbone of our information-driven society. However, we are on the verge of reaching the fundamental limit of single-mode fibre transmission capacity. Therefore, a new means to increase the transmission capacity of optical fibre is essential to avoid a capacity crunch. Here, by employing few-mode multicore fibre, compact three-dimensional waveguide multiplexers and energy-efficient frequency-domain multiple-input multiple-output equalization, we demonstrate the viability of spatial multiplexing to reach a data rate of 5.1 Tbit s−1 carrier−1 (net 4 Tbit s−1 carrier−1) on a single wavelength over a single fibre. Furthermore, by combining this approach with wavelength division multiplexing with 50 wavelength carriers on a dense 50 GHz grid, a gross transmission throughput of 255 Tbit s−1 (net 200 Tbit s−1) over a 1 km fibre link is achieved. A few-mode, multicore fibre allows ultra-high-speed data transmission on a single wavelength of light.

Grip Strength Cutpoints for the Identification of Clinically Relevant Weakness

Abstract: Muscle weakness is related to poor physical performance and incident mobility limitations among older adults (1–6). Weakness is considered a key element of frailty (7) and, increasingly, of sarcopenia (8,9). Although the association between weakness and functional limitations is strong, there is no consensus regarding a cutpoint for identification of risk for functional problems. In order to identify population subgroups in whom weakness is a potential contributor to functional limitations, it is necessary to determine what constitutes a clinically relevant degree of weakness. This is the second in a series of reports from the Foundation for the National Institutes of Health (FNIH) Sarcopenia Project, which pooled data from multiple studies to develop and evaluate clinically relevant criteria for weakness and low muscle mass (10). The purpose of the analysis presented here was to identify cutpoints that distinguish weakness (measured by grip strength) associated with mobility impairment (measured by gait speed) using cross-sectional data (ie, to maximize concurrent validity). This analysis builds on previous research on the association between strength and walking speed using a data-driven approach across multiple populations and an analytic technique (Classification and Regression Tree [CART] analysis) designed to optimize concurrent validity in the context of complex interactions. Findings were used to address subsequent Project goals reported separately (11–13).

The generation, characterization and applications of broadband isolated attosecond pulses

Abstract: The generation of extremely short isolated attosecond pulses requires both a broad spectral bandwidth and control of the spectral phase. Rapid progress has been made in both aspects, leading to the generation of light pulses as short as 67 as in 2012, and broadband attosecond continua covering a wide range of extreme ultraviolet and soft X-ray wavelengths. Such pulses have been successfully applied in photoelectron and photoion spectroscopy and recently developed attosecond transient absorption spectroscopy to study electron dynamics in matter. In this Review, we discuss significant recent advances in the generation, characterization and applications of ultrabroadband, isolated attosecond pulses with spectral bandwidths comparable to the central frequency. These pulses can in principle be compressed to a single optical cycle. This review discusses significant recent advances in the generation, characterization and application of ultrabroadband isolated attosecond pulses with a spectral bandwidth comparable to the central frequency, which can in principle be compressed to a single optical cycle.

Criteria for Clinically Relevant Weakness and Low Lean Mass and Their Longitudinal Association With Incident Mobility Impairment and Mortality: The Foundation for the National Institutes of Health (FNIH) Sarcopenia Project

Abstract: Results. Low grip strength (men: odds ratio (OR) = 2.31, 95% confidence interval (CI) = 1.34-3.99; women: OR = 1.99, 95% CI 1.23-3.21), low grip strength-to-BMI ratio (men: OR = 3.28, 95% CI 1.92-5.59; women: OR = 2.54, 95% CI 1.10-5.83) and low ALM-to-BMI ratio (men: OR = 1.58, 95% CI 1.12-2.25; women: OR = 1.81, 95% CI 1.14-2.87), but not low ALM, were associated with increased likelihood for incident mobility impairment. Weakness increased likelihood of mobility impairment regardless of low lean mass. Mortality risk patterns were inconsistent. Conclusions. These findings support our cut-points for low grip strength and low ALM-to-BMI ratio as candidate criteria for clinically relevant weakness and low lean mass. Further validation in other populations and for alternate relevant outcomes is needed.

2-dimensional transition metal dichalcogenides with tunable direct band gaps: MoS₂(₁-x) Se₂x monolayers.

Abstract: MoS2(1-x) Se2x single-layer films are prepared using a mixture of organic selenium and sulfur precursors as well as a solid molybdenum source. The direct bandgaps are found to scale nearly linearly with composition in the range of 1.87 eV (pure single-layer MoS2 ) to 1.55 eV (pure single-layer MoSe2 ) permitting straightforward bandgap engineering.

An Evidence-Based Comparison of Operational Criteria for the Presence of Sarcopenia

Abstract: Low muscle mass and weakness are potential contributors to disability in older persons. Although the term “sarcopenia” has become widespread, the criteria for an operational definition vary among studies and experts. Initial work on defining sarcopenia was based on measures of muscle mass alone, and the prevalence of sarcopenia when compared with a young reference population ranged between 13% and 24% among adults younger than 70 years to more than 50% among adults older than 80 years (1). However, a growing body of research suggests that there is a disconnect between muscle mass and strength. Thus, recent definitions of sarcopenia have incorporated elements of strength and physical performance in addition to muscle mass in the criteria for sarcopenia (2–5). However, these consensus statements were based on expert opinions and lacked access to large data sets to validate their recommendations. Thus, the goal of the Foundation for the National Institutes of Health (FNIH) Sarcopenia Project was to create a data-driven set of criteria for clinically relevant weakness and low lean mass using pooled data from multiple studies. This is the fifth report of the FNIH Sarcopenia Project. The first manuscript describes the rationale for the FNIH Sarcopenia Project and characteristics of the participating studies. The second and third manuscripts describe in detail the development of cutpoints for weakness and low lean mass; and the fourth manuscript demonstrates the predictive validity of these cutpoints. The purpose of the analyses presented here is to compare the criteria developed by the FNIH project to other published criteria, in order to assess prevalence, agreement, and discrepancies between candidate criteria. Our goal is to provide data-driven evidence to the field in order to advance professional consensus regarding clinically relevant cutpoints and terminology.

Integrated flexible chalcogenide glass photonic devices

Abstract: Photonic integration on thinflexible plastic substrates is important for emerging applications ranging from the realization of flexible interconnects to conformal sensors applied to the skin. Such devices are traditionally fabricated using pattern transfer, which is complicated and has limited integration capacity. Here, we report a convenient monolithic approach to realize flexible, integrated high-index-contrast chalcogenide glass photonic devices. By developing local neutral axis designs and suitable fabrication techniques, we realize a suite of photonic devices including waveguides, microdisk resonators, add–drop filters and photonic crystals that have excellent optical performance and mechanical flexibility, enabling repeated bending down to sub-millimetre radii without measurable performance degradation. The approach offers a facile fabrication route for three-dimensional high-index-contrast photonics that are difficult to create using traditional methods.

Cutpoints for Low Appendicular Lean Mass That Identify Older Adults With Clinically Significant Weakness

Abstract: Early efforts to create an operational definition of sarcopenia (including the creation of cutpoints) have relied on distributional definitions of lean mass (1), with sarcopenia defined as a value of appendicular lean mass (ALM)/height2 (derived from whole-body dual-energy x-ray absorptiometry [DXA]) below the young adult mean level of lean mass or was based on definitions that further account for body size or fatness (2–4). More recent efforts have added functional and/or strength measures to lean mass to define sarcopenia (5,6), but no approaches thus far have proposed and validated cutpoints and definitions based on discriminative and predictive ability using a data-driven approach from a variety of cohort studies. The overarching goal of this set of concurrent reports from the Foundation for the National Institutes of Health (FNIH) Sarcopenia Project was to determine preliminary data-driven criteria for clinically relevant weakness and low lean mass. The conceptual framework was based on a clinician making a “differential diagnosis” of mobility impairment, defined as slow gait speed. The clinician understands that there are many causes of slow walking, one of which is weakness. Similarly, low lean mass may be considered a potential contributing factor to the development of weakness (7). Data from multiple large cohort studies of aging were pooled for this effort (7). The first stage of analyses identified sex-specific cutpoints for weakness that discriminated slow participants (walking speed <0.8 m/s) from those who walked faster (8). In the second stage of the analyses, reported herein, we aimed to identify cutpoints in lean mass that discriminated those who were weak (grip strength <16kg in women or <26kg in men) from those who were stronger. The findings from this work were used to address subsequent goals of the Project, so it is important to consider these results within the context of all other articles in this series.

Climate fails to predict wood decomposition at regional scales

Abstract: spatial scale from which they are inferred. We show that the common assumption that climate is a predominant control on decomposition is supported only when local-scale variation is aggregated into mean values. Disaggregated data instead reveal that local-scale factors explain 73% of the variation in wood decomposition, and climate only 28%. Further, the temperature sensitivity of decomposition estimated from local versus mean analyses is 1.3-times greater. Fundamental issues with mean correlations were highlighted decades ago 9,10 , yet mean climate‐decomposition relationships are used to generate simulations that inform management and adaptation under environmental change. Our results suggest that to predict accurately how decomposition will respond to climate change, models must account for local-scale factors that control regional dynamics. Climate is traditionally thought to be the predominant control on decomposition rates at global and regional scales, with biotic factors controlling only local rates 2,4 . Biotic factors are divided into decomposer organisms, such as soil microbes, and the quality (for example, chemical composition) of the plant litter they decompose. Recent work suggests that litter quality may be more important than climate in controlling decomposition rates across biomes worldwide 3,11 , but the influence of decomposer organisms is still assumed limited across broad climate gradients 12 . A core reason for this assumption is that climate is considered a primary control on the activity of decomposers. As such, across climate gradients, mean temperature and moisture availability are assumed to explain much of the variation in the activity of decomposer organisms and hence decomposition rates of organic matter. These climatedecomposition relationships are used to parameterize and evaluate Earth-system models 13 . It is therefore important to test the assumption that climate drives decomposer activities because proper understanding of these activities is needed to inform model projections such as carbon cycleclimate

Molecular adsorption on graphene

Abstract: Current studies addressing the engineering of charge carrier concentration and the electronic band gap in epitaxial graphene using molecular adsorbates are reviewed. The focus here is on interactions between the graphene surface and the adsorbed molecules, including small gas molecules (H(2)O, H(2), O(2), CO, NO(2), NO, and NH(3)), aromatic, and non-aromatic molecules (F4-TCNQ, PTCDA, TPA, Na-NH(2), An-CH(3), An-Br, Poly (ethylene imine) (PEI), and diazonium salts), and various biomolecules such as peptides, DNA fragments, and other derivatives. This is followed by a discussion on graphene-based gas sensor concepts. In reviewing the studies of the effects of molecular adsorption on graphene, it is evident that the strong manipulation of graphene's electronic structure, including p- and n-doping, is not only possible with molecular adsorbates, but that this approach appears to be superior compared to these exploiting edge effects, local defects, or strain. However, graphene-based gas sensors, albeit feasible because huge adsorbate-induced variations in the relative conductivity are possible, generally suffer from the lack of chemical selectivity.

Single-Layer MoS2 with Sulfur Vacancies: Structure and Catalytic Application

Abstract: Single-layer MoS2 is proving to be a versatile material for a wide variety of electronic, optical, and chemical applications. Sulfur depletion, without destabilization of the single layer, is considered a prudent way for making the basal plane of the layer catalytically active. Based on the results of our density-functional-theory examination of vacancy structures on one side of an MoS2 layer, we show that the formation energy per sulfur vacancy is the lowest (energetically favorable) when the vacancies form a row and that the longer the row, the lower the formation energy. In addition, we find that the lowest energy barrier for the diffusion of sulfur vacancy at the row structures through the exchange of a vacancy with a nearby sulfur atom is 0.79 eV and that this barrier increases as the row elongates. We also evaluate the propensity for catalytic activity of an MoS2 layer with two types of sulfur-vacancy structures (row and patch) and find the energetics for alcohol synthesis from syngas to be more fav...

The Role of Hypoxia-Inducible Factor in Wound Healing.

Abstract: Significance: Poor wound healing remains a significant health issue for a large number of patients in the United States. The physiologic response to local wound hypoxia plays a critical role in determining the success of the normal healing process. Hypoxia-inducible factor-1 (HIF-1), as the master regulator of oxygen homeostasis, is an important determinant of healing outcomes. HIF-1 contributes to all stages of wound healing through its role in cell migration, cell survival under hypoxic conditions, cell division, growth factor release, and matrix synthesis throughout the healing process. Recent Advances: Positive regulators of HIF-1, such as prolyl-4-hydroxylase inhibitors, have been shown to be beneficial in enhancing diabetic ischemic wound closure and are currently undergoing clinical trials for treatment of several human-ischemia-based conditions. Critical Issues: HIF-1 deficiency and subsequent failure to respond to hypoxic stimuli leads to chronic hypoxia, which has been shown to contribute to the formation of nonhealing ulcers. In contrast, overexpression of HIF-1 has been implicated in fibrotic disease through its role in increasing myofibroblast differentiation leading to excessive matrix production and deposition. Both positive and negative regulators of HIF-1 therefore provide important therapeutic targets that can be used to manipulate HIF-1 expression where an excess or deficiency in HIF-1 is known to correlate with pathogenesis. Future Directions: Targeting HIF-1 during wound healing has many important clinical implications for tissue repair. Counteracting the detrimental effects of excessive or deficient HIF-1 signaling by modulating HIF-1 expression may improve future management of poorly healing wounds.

Impact of Health Literacy on Medication Adherence A Systematic Review and Meta-analysis

Abstract: Objective To systematically review the literature and estimate the effect size of the relationship between health literacy and medication adherence through meta-analysis. Data sources Databases searched included Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982-2013), International Pharmaceutical Abstracts (IPA; 1970-2013), MEDLINE OVID (1966-2013), PubMed (1966-2013), PsycInfo (1966-2013), and Web of Science (1966-2013). Study selection and data extraction Inclusion criteria were as follows: English language; published through May 1, 2013; medication adherence as the outcome variable; use of validated measures of health literacy and medication adherence; availability of a direct (not mediating) relationship between health literacy and medication adherence; and identifiable effect size and statistical significance of the relationship. Exclusion criteria were as follows: duplicated results, irrelevant results, conference abstracts, proceeding papers, books, dissertations, reviews, editorial letters, continuing education units, or book reviews. Data included author, publication year, disease area, sample size, sampling method, location, study design, effect size of the relationship between health literacy and medication adherence, and measures of health literacy and medication adherence. Data synthesis There is a small statistically significant and positive association between health literacy and medication adherence. In the conservative results, the unweighted and weighted correlation coefficients were 0.081 and 0.056 with P values Conclusions The relationship between health literacy and medication adherence is statistically significant but weak. It is plausible that health literacy has a mediator relationship with other adherence determinants. Future research should explore such relationships.

Action Recognition in Realistic Sports Videos

Abstract: The ability to analyze the actions which occur in a video is essential for automatic understanding of sports. Action localization and recognition in videos are two main research topics in this context. In this chapter, we provide a detailed study of the prominent methods devised for these two tasks which yield superior results for sports videos. We adopt UCF Sports, which is a dataset of realistic sports videos collected from broadcast television channels, as our evaluation benchmark. First, we present an overview of UCF Sports along with comprehensive statistics of the techniques tested on this dataset as well as the evolution of their performance over time. To provide further details about the existing action recognition methods in this area, we decompose the action recognition framework into three main steps of feature extraction, dictionary learning to represent a video, and classification; we overview several successful techniques for each of these steps. We also overview the problem of spatio-temporal localization of actions and argue that, in general, it manifests a more challenging problem compared to action recognition. We study several recent methods for action localization which have shown promising results on sports videos. Finally, we discuss a number of forward-thinking insights drawn from overviewing the action recognition and localization methods. In particular, we argue that performing the recognition on temporally untrimmed videos and attempting to describe an action, instead of conducting a forced-choice classification, are essential for analyzing the human actions in a realistic environment.

Effects of modifications of bamboo cellulose fibers on the improved mechanical properties of cellulose reinforced poly(lactic acid) composites

Abstract: Three kinds of modifications, alkali soaking or silane coupling cellulose and maleic anhydride grafting poly( l -lactic acid), were applied in the preparation of cellulose/poly( l -lactic acid) composites The effects of treatments of the cellulosic fibers on the mechanical properties of cellulose/poly( l -lactic acid) composites were comparatively investigated The results demonstrated that the alkali soaking provided the composites with highest strength and Young’s modulus, increased by 286% and 346%, respectively, than untreated samples The highest impact toughness and elongation were achieved by silane agent pretreatment, which were 115% and 62% higher than those of poly( l -lactic acid) reinforced with virgin bamboo cellulosic fibers Maleic anhydride grafting had moderate effects on both the stiffness and ductility, exhibiting best over-all properties From the scanning electron microscopy observations and Fourier transform infrared spectrum analysis, it was found that the interfacial interactions between the filler and matrix were improved after all the modifications mentioned

Photoluminescence Quenching in Single-Layer MoS$_{2}$ via Oxygen Plasma Treatment

Abstract: By creating defects via oxygen plasma treatment, we demonstrate optical properties variation of single-layer MoS2. We found that, with increasing plasma exposure time, the photoluminescence (PL) evolves from very high intensity to complete quenching, accompanied by gradual reduction and broadening of MoS2 Raman modes, indicative of distortion of the MoS2 lattice after oxygen bombardment. X-ray photoelectron spectroscopy study shows the appearance of the Mo6+ peak, suggesting the creation of MoO3 disordered regions in the MoS2 flake. Finally, using band structure calculations, we demonstrate that the creation of MoO3 disordered domains upon exposure to oxygen plasma leads to a direct-to-indirect bandgap transition in single-layer MoS2, which explains the observed PL quenching.

MicroRNA expressions associated with progression of prostate cancer cells to antiandrogen therapy resistance

Abstract: Development of resistance to androgen deprivation therapy (ADT) is a major obstacle for the management of advanced prostate cancer. Therapies with androgen receptor (AR) antagonists and androgen withdrawal initially regress tumors but development of compensatory mechanisms including AR bypass signaling leads to re-growth of tumors. MicroRNAs (miRNAs) are small regulatory RNAs that are involved in maintenance of cell homeostasis but are often altered in tumor cells. In this study, we determined the association of genome wide miRNA expression (1113 unique miRNAs) with development of resistance to ADT. We used androgen sensitive prostate cancer cells that progressed to ADT and AR antagonist Casodex (CDX) resistance upon androgen withdrawal and treatment with CDX. Validation of expression of a subset of 100 miRNAs led to identification of 43 miRNAs that are significantly altered during progression of cells to treatment resistance. We also show a correlation of altered expression of 10 proteins targeted by some of these miRNAs in these cells. We conclude that dynamic alterations in miRNA expression occur early on during androgen deprivation therapy, and androgen receptor blockade. The cumulative effect of these altered miRNA expression profiles is the temporal modulation of multiple signaling pathways promoting survival and acquisition of resistance. These early events are driving the transition to castration resistance and cannot be studied in already developed CRPC cell lines or tissues. Furthermore our results can be used a prognostic marker of cancers with a potential to be resistant to ADT.