503 research outputs found

    Racial Barriers to African American Entrepreneurship: An Exploratory Study

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    Much has been written in the ethnic entrepreneurship literature about the contrasting business performance of African American entrepreneurs and those from other minority and immigrant groups. Yet very little research has been conducted by social scientists on the business experiences of black entrepreneurs. In this exploratory study we examine the situation of black contractors in the U.S. construction industry, utilizing 76 in-depth interviews in one of the South\u27s metropolitan areas. We document the nuanced character of the racial barriers faced by black contractors in several areas of the construction industry. We find racial discrimination in unions, in white general contractors\u27 contracting and bidding processes, in construction project conditions, and in the bonding, lending, supplier networks critical to a successful construction business. Looking at persisting discrimination theoretically, we suggest examination of the cumulative, interlocking, and externally-amplified dimensions of discrimination. Our empirical and conceptual analyses provide a start toward understanding how discrimination is organized in a major U.S. industrial sector long neglected in social science research

    Art Is I, Science Is We

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    The expression of the title has been used for some time to produce a concise summary of the major distinction between “art” and “science.” Our goal is to give a fuller and deeper understanding of this statement by discussing its meaning and interpretation within the context of a precise definition of science. We conclude that “Art is I, science is we,” captures accurately the fundamental difference between these two disciplines

    Insights into galvanic corrosion behavior of Ti-Cu dissimilar joint: Effect of microstructure and volta potential

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    The effect of microstructure on corrosion behavior of a solid-state explosion welded Ti-Cu bimetal is investigated by means of alternating current-direct current (AC-DC) electrochemical measurements, optical microscopy, scanning electron microscopy, and scanning Kelvin probe force microscopy (SKPFM). The results indicate that the titanium regions in the welding interface, local melted zone (LMZ), and LMZ-Cu interface are potential sites for initiation of corrosion attacks. SKPFM mapping clearly shows that before exposure of the sample to a 3.5% NaCl corrosive solution and at the beginning of the exposure, the Cu side of the bimetal has a higher Volta potential in comparison to that of the Ti region, and thus acts as a cathode. Electrochemical measurements also confirm that titanium acts as an anode and copper as a cathode, in the first moments of immersion, in accordance with macroscopic observations and SKPFM results. However, by growing a passive layer of titanium oxide and titanium hydroxide on the Ti side after about 1 h exposure to the corrosive medium, the titanium side becomes nobler and the polarity arrangement in the galvanic couple reverses

    Stratospheric Effects on UV, Speed of Sound, Pressure, and Temperature

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    The atmosphere is composed of several layers, each with its own distinct environment varying in temperature, pressure, and levels of UV radiation. Quantifying these varying parameters proves to be useful in understanding atmospheric composition in greater detail. Variance in the composition of the atmosphere allows for the study of the evolution of physical phenomena at different altitudes. Our group quantified this variance using a high-altitude weather balloon and designed an experimental method to observe the nature of sound propagation through varying altitudes. The goal was to develop an altitude-dependent model of the speed of sound by using an open-air, microcontroller-based payload. Using our platform, we found that the open-air payload design results in noisy readings. Additionally, our method was restricted to low altitude environments, unable to produce reliable data above 6,700 meters. We address possible improvements and constraints in developing an open-air payload design to derive an altitude-dependent model for sound propagation. Furthermore, we present our findings on the variations in pressure, temperature, and levels of UV radiation during balloon flights at altitudes of up to 30,000 meters. These variations included a proportional decrease in pressure, a temperature inversion at 15,000 meters, and an exceptional increase in both UVA and UVB radiation as altitude increases

    Prioritising Health in Mobility Planning:Assessing Health and co-benefits in European Sustainable Urban Mobility Plans

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    Transport can influence health both positively and negatively through various detrimental and beneficial pathways. Transport policies that promote health offer major environmental and economic co-benefits and are critical for achieving the United Nations Sustainable Development Goals. To date, few studies have empirically examined the degree to which health goals and outcomes have been incorporated into urban mobility plans. This work assesses how much health is addressed in current Sustainable Urban Mobility Plans (SUMPs), including the extent to which: i) health and its various aspects like health equity are highlighted, ii) transport pathways to health and their associated health outcomes are made explicit, and iii) health is operationalised into targets and KPIs and the health-rationale of various actions and measures is elaborated. A three-step method is used: i) developing a health dictionary and a policy analysis checklist, ii) conducting a quantitative text analysis on a dataset of 230 SUMPs, and iii) performing a detailed qualitative analysis of a purposive sample of 13 SUMPs across Europe. The findings show that while health is often touched upon, and its prominence seems to be increasing, SUMPs miss out on the opportunity to embrace mobility as a driver of health promotion. The link between transport and equity, and social and mental wellbeing is not frequently discussed. Detailed targets and key performance indicators (KPIs) for several health pathways are scarce or missing, as are the health rationale and health outcomes for proposed measures. Overwhelmingly SUMPs’ health aspirations are concerned with minimising detrimental impacts of transport on health, primarily from traffic injuries and to a lesser extent from air pollution. Health related concepts such as accessibility and active travel feature prominently but are not seen as an opportunity to enhance health. It is recommended to highlight the role of transport policy not only in reducing adverse health effects, but also as an opportunity for health enhancement.</div

    Meaning in life in psychotherapy: The perspective of experienced psychotherapists

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    Objective Our goal was to explore the meaning experienced psychotherapists derive from providing psychotherapy, their beliefs about the role of meaning in life (MIL) in psychotherapy, how they worked with MIL with a client who explicitly presented concerns about MIL, and how they worked with a different client for whom MIL was a secondary and more implicit concern. Method Thirteen experienced psychotherapists were interviewed and data were analyzed using consensual qualitative research. Results Therapists derived self-oriented meaning (e.g., feeling gratified, fulfilled, connected) and other-oriented meaning (helping others, making the world a better place) from providing psychotherapy. They believed that MIL is fundamental and underlies all human concerns, including those brought to therapy. In contrast to the clients who had implicit MIL concerns, clients who explicitly presented MIL concerns were reported to have more interpersonal problems and physical problems, but about the same amount of psychological distress and loss/grief. Therapists used insight-oriented interventions, support, action-oriented interventions, and exploratory interventions to work with MIL with both types of clients, but used more exploratory interventions with implicit than explicit MIL clients. Conclusions MIL is a salient topic for experienced, existentially oriented psychotherapists; they work with MIL extensively with some clients in psychotherapy. We recommend that therapists receive training to work with MIL in therapy, and that they pay attention to MIL concerns when they conduct psychotherapy. We also recommend additional research on MIL in psychotherapy

    Deep Learning-based Approach for the Semantic Segmentation of Bright Retinal Damage

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    Regular screening for the development of diabetic retinopathy is imperative for an early diagnosis and a timely treatment, thus preventing further progression of the disease. The conventional screening techniques based on manual observation by qualified physicians can be very time consuming and prone to error. In this paper, a novel automated screening model based on deep learning for the semantic segmentation of exudates in color fundus images is proposed with the implementation of an end-to-end convolutional neural network built upon UNet architecture. This encoder-decoder network is characterized by the combination of a contracting path and a symmetrical expansive path to obtain precise localization with the use of context information. The proposed method was validated on E-OPHTHA and DIARETDB1 public databases achieving promising results compared to current state-of-theart methods.This paper was supported by the European Union’s Horizon 2020 research and innovation programme under the Project GALAHAD [H2020-ICT2016-2017, 732613]. The work of Adri´an Colomer has been supported by the Spanish Government under a FPI Grant [BES-2014-067889]. We gratefully acknowledge the support of NVIDIA Corporation with the donation of the Titan Xp GPU used for this research.Silva, C.; Colomer, A.; Naranjo Ornedo, V. (2018). Deep Learning-based Approach for the Semantic Segmentation of Bright Retinal Damage. En Intelligent Data Engineering and Automated Learning – IDEAL 2018. Springer. 164-173. https://doi.org/10.1007/978-3-030-03493-1_18S164173World Health Organization: Diabetes fact sheet. Sci. Total Environ. 20, 1–88 (2011)Verma, L., Prakash, G., Tewari, H.K.: Diabetic retinopathy: time for action. No complacency please! Bull. 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    Height-diameter allometry and above ground biomass in tropical montane forests: Insights from the Albertine Rift in Africa

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    Tropical montane forests provide an important natural laboratory to test ecological theory. While it is well-known that some aspects of forest structure change with altitude, little is known on the effects of altitude on above ground biomass (AGB), particularly with regard to changing height-diameter allometry. To address this we investigate (1) the effects of altitude on height-diameter allometry, (2) how different height-diameter allometric models affect above ground biomass estimates; and (3) how other forest structural, taxonomic and environmental attributes affect above ground biomass using 30 permanent sample plots (1-ha; all trees ≥ 10 cm diameter measured) established between 1250 and 2600 m asl in Kahuzi Biega National Park in eastern Democratic Republic of Congo. Forest structure and species composition differed with increasing altitude, with four forest types identified. Different height-diameter allometric models performed better with the different forest types, as trees got smaller with increasing altitude. Above ground biomass ranged from 168 to 290 Mg ha-1, but there were no significant differences in AGB between forests types, as tree size decreased but stem density increased with increasing altitude. Forest structure had greater effects on above ground biomass than forest diversity. Soil attributes (K and acidity, pH) also significantly affected above ground biomass. Results show how forest structural, taxonomic and environmental attributes affect above ground biomass in African tropical montane forests. They particularly highlight that the use of regional height-diameter models introduces significant biases in above ground biomass estimates, and that different height-diameter models might be preferred for different forest types, and these should be considered in future studies

    Adjuvant drugs for peripheral nerve blocks: The role of nmda antagonists, neostigmine, epinephrine, and sodium bicarbonate

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    The potential for misuse, overdose, and chronic use has led researchers to look for other methods to decrease opioid consumption in patients with acute and chronic pain states. The use of peripheral nerve blocks for surgery has gained increasing popularity as it minimizes peripheral pain signals from the nociceptors of local tissue sustaining trauma and inflammation from surgery. The individualization of peripheral nerve blocks using adjuvant drugs has the potential to improve patient outcomes and reduce chronic pain. The major limitations of peripheral nerve blocks are their limited duration of action and dose-dependent adverse effects. Adjuvant drugs for peripheral nerve blocks show increasing potential as a solution for postoperative and chronic pain with their synergistic effects to increase the duration of action and decrease the required dosage of local anesthetic. N-methyl-d-aspartate (NMDA) receptor antagonists are a viable option for patients with opioid resistance and neuropathic pain due to their affinity to the neurotransmitter glutamate, which is released when patients experience a noxious stimulus. Neostigmine is a cholinesterase inhibitor that exerts its effect by competitively binding at the active site of acetylcholinesterase, which prevents the hydrolysis of acetylcholine and subsequently retaining acetylcholine at the nerve terminal. Epinephrine, also known as adrenaline, can potentially be used as an adjuvant to accelerate and prolong analgesic effects in digital nerve blocks. The theorized role of sodium bicarbonate in local anesthetic preparations is to increase the pH of the anesthetic. The resulting alkaline solution enables the anesthetic to more readily exist in its un-ionized form, which more efficiently crosses lipid membranes of peripheral nerves. However, more research is needed to show the efficacy of these adjuvants for nerve block prolongation as studies have been either mixed or have small sample sizes
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