9,266 research outputs found
Feasibility Of One–Dedicated–Lane Bus Rapid Transit ⁄Light–Rail Systems And Their Expansion To Two–Dedicated–Lane Systems: A Focus On Geometric Configuration And Performance Planning, MTI Report 08-01
This report consists primarily of two parts, the first on feasibility and the next on space minimization. In the section on feasibility, we propose the concept of a Bus Rapid Transit (BRT) or light–rail system that effectively requires only one dedicated but reversible lane throughout the system to support two-way traffic in the median of a busy commute corridor with regular provision of left–turn lanes. Based on key ideas proposed in that section, the section on space minimization first addresses how to implement a two–dedicated–lane BRT or light–rail system with minimum right–of–way width and then proposes ways to expand a one–dedicated–lane system to two dedicated lanes. In a one–dedicated–lane system, traffic crossing is accommodated on the otherwise unused or underused median space resulting from provision of the left–turn lanes. Although not necessary, some left–turn lanes can be sacrificed for bus stops. Conceptual design options and geometric configuration sketches for the bus stop and crossing space are provided in the section on feasibility, which also discusses system performance in terms of travel speed, headway of operations, distance between two neighboring crossing spaces, and number of crossing spaces. To ensure practicality, we study implementation of such a system on an existing corridor. Such a system is also useful as an intermediate step toward a two–dedicated–lane system because of its potential for facilitating transit–oriented development. In typical existing or planned BRT or light–rail systems implemented with two dedicated traffic lanes, a space equivalent to four traffic lanes is dedicated for a bus stop. In the section on space minimization, we propose implementations requiring only three lanes at a bus stop, based on two key ideas proposed for a one–dedicated–lane system. That section also discusses ways to expand a one–dedicated–lane system to its corresponding two–dedicated–lane system
Effects of noise suppression and envelope dynamic range compression on the intelligibility of vocoded sentences for a tonal language
Vocoder simulation studies have suggested that the carrier signal type employed affects the intelligibility of vocoded speech. The present work further assessed how carrier signal type interacts with additional signal processing, namely, single-channel noise suppression and envelope dynamic range compression, in determining the intelligibility of vocoder simulations. In Experiment 1, Mandarin sentences that had been corrupted by speech spectrum-shaped noise (SSN) or two-talker babble (2TB) were processed by one of four single-channel noise-suppression algorithms before undergoing tone-vocoded (TV) or noise-vocoded (NV) processing. In Experiment 2, dynamic ranges of multiband envelope waveforms were compressed by scaling of the mean-removed envelope waveforms with a compression factor before undergoing TV or NV processing. TV Mandarin sentences yielded higher intelligibility scores with normal-hearing (NH) listeners than did noise-vocoded sentences. The intelligibility advantage of noise-suppressed vocoded speech depended on the masker type (SSN vs 2TB). NV speech was more negatively influenced by envelope dynamic range compression than was TV speech. These findings suggest that an interactional effect exists between the carrier signal type employed in the vocoding process and envelope distortion caused by signal processing
A Cortical Region Consisting Entirely of Face-Selective Cells
Face perception is a skill crucial to primates. In both humans and macaque monkeys, functional magnetic resonance imaging (fMRI) reveals a system of cortical regions that show increased blood flow when the subject views images of faces, compared with images of objects. However, the stimulus selectivity of single neurons within these fMRI-identified regions has not been studied. We used fMRI to identify and target the largest face-selective region in two macaques for single-unit recording. Almost all (97%) of the visually responsive neurons in this region were strongly face selective, indicating that a dedicated cortical area exists to support face processing in the macaque
Object Recognition: Physiological and Computational Insights
Visual object recognition is the identification of a thing in the outside world based on the sense of vision. Our eyes are bombarded by a wide variety of visual forms, from simple shapes like cups an
A Pilot Study: The Beneficial Effects of Combined Statin-exercise Therapy on Cognitive Function in Patients with Coronary Artery Disease and Mild Cognitive Decline.
Objective Hypercholesterolemia, a risk factor in cognitive impairment, can be treated with statins. However, cognitive decline associated with "statins" (HMG-CoA reductase inhibitors) is a clinical concern. This pilot study investigated the effects of combining statins and regular exercise on cognitive function in coronary artery disease (CAD) patients with prior mild cognitive decline. Methods We recruited 43 consecutive CAD patients with mild cognitive decline. These patients were treated with a statin and weekly in-hospital aerobic exercise for 5 months. We measured serum lipids, exercise capacity, and cognitive function using the mini mental state examination (MMSE). Results Low-density lipoprotein cholesterol levels were significantly decreased, and maximum exercise capacity (workload) was significantly increased in patients with CAD and mild cognitive decline after treatment compared with before. Combined statin-exercise therapy significantly increased the median (range) MMSE score from 24 (22-25) to 25 (23-27) across the cohort (p<0.01). Changes in body mass index (BMI) were significantly and negatively correlated with changes in the MMSE. After treatment, MMSE scores in the subgroup of patients that showed a decrease in BMI were significantly improved, but not in the BMI-increased subgroup. Furthermore, the patients already on a statin at the beginning of the trial displayed a more significant improvement in MMSE score than statin-naïve patients, implying that exercise might be the beneficial aspect of this intervention as regards cognition. In a multivariate logistic regression analysis adjusted for age >65 years, sex, and presence of diabetes mellitus, a decrease in BMI during statin-exercise therapy was significantly correlated with an increase in the MMSE score (odds ratio: 4.57, 95% confidence interval: 1.05-20.0; p<0.05). Conclusion Statin-exercise therapy may help improve cognitive dysfunction in patients with CAD and pre-existing mild cognitive decline
The application of ultrasonic NDT techniques in tribology
The use of ultrasonic reflection is emerging as a technique for studying tribological contacts. Ultrasonic waves can be transmitted non-destructively through machine components and their behaviour at an interface describes the characteristics of that contact. This paper is a review of the current state of understanding of the mechanisms of ultrasonic reflection at interfaces, and how this has been used to investigate the processes of dry rough surface contact and lubricated contact. The review extends to cover how ultrasound has been used to study the tribological function of certain engineering machine elements
Current Status of Herbal Medicines in Chronic Liver Disease Therapy: The Biological Effects, Molecular Targets and Future Prospects
Chronic liver dysfunction or injury is a serious health problem worldwide. Chronic liver disease involves a wide range of liver pathologies that include fatty liver, hepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. The efficiency of current synthetic agents in treating chronic liver disease is not satisfactory and they have undesirable side effects. Thereby, numerous medicinal herbs and phytochemicals have been investigated as complementary and alternative treatments for chronic liver diseases. Since some herbal products have already been used for the management of liver diseases in some countries or regions, a systematic review on these herbal medicines for chronic liver disease is urgently needed. Herein, we conducted a review describing the potential role, pharmacological studies and molecular mechanisms of several commonly used medicinal herbs and phytochemicals for chronic liver diseases treatment. Their potential toxicity and side effects were also discussed. Several herbal formulae and their biological effects in chronic liver disease treatment as well as the underlying molecular mechanisms are also summarized in this paper. This review article is a comprehensive and systematic analysis of our current knowledge of the conventional medicinal herbs and phytochemicals in treating chronic liver diseases and on the potential pitfalls which need to be addressed in future study. © 2015 by the authors; licensee MDPI, Basel, Switzerland.published_or_final_versio
Red pigment from Saw Palmetto: a natural product for potential alternative cancer treatment
Conference Theme: Anticancer Drug Action and Drug Resistance: from Cancer Biology to the ClinicINTRODUCTION: Saw palmetto is extract of the fruit of Serenoa repens (Bartram) J.K.Small, an edible plant originated from the Southeastern United States. It has been used in traditional, complementary and
alternative medicine as a tonic, expectorant and antiseptic for treatment of various illnesses, especially urinary and reproductive system problems. Approximately 90% of Saw palmetto containing fatty acids and has been claimed for its therapeutic effect on benign prostatic hyperplasia (BPH). Previous studies also suggested the in vitro and in vivo anti-cancer effect of lipidosterolic extract of Saw Palmetto. However, recent epidemiology and randomized trials ...published_or_final_versio
Berberine and Coptidis Rhizoma as novel antineoplastic agents: A review of traditional use and biomedical investigations
Ethnopharmacological relevance: Coptidis Rhizoma (Huanglian) and its major component, berberine, have drawn extensive attention toward their antineoplastic effects in the recent years. The antineoplastic effects are related to the Chinese Medicine (CM) properties of Huangliang in treating diseases by removing damp-heat and purging fire and counteracting toxicity. Aim of the review: To trace the long history of the traditional use of Huanglian from folk medicines, especially from Chinese medicine, to recent pharmacological studies of Huanglian and berberine, with an emphasis on their antineoplastic effects and the promise as novel antineoplastic agents. Methods: A total of seven databases were extensively searched for literature research. The terms and keywords for searching included Huanglian, berberine, Coptis, Coptidis Rhizoma, anticancer, anti-invasion, antimatastasis and mechanism. The papers including ours with studies on anticancer and mechanism, pharmacology and toxicology of Huanglian and/or berberine were focused. Results: In view of traditional use, the anticancer effects of Huanglian can be ascribed to its CM trait by removing damp-heat, fire and toxicity. From modern biomedical studies, anticancer effects have been demonstrated in both Huanglian and berberine. The underlying molecular mechanisms involve cell-cycle arrest, apoptosis induction and anti-inflammation. Berberine is an essential anticancer compound in Huanglian. In some studies, the use of Huanglian was shown to be more effective and beneficial than the use of berberine alone. The presence of other protoberberine-type alkaloids in Huanglian might give synergistic effects for the anticancer effects. Berberine also demonstrates effects of antiangiogenesis, anti-invasion and anti-metastasis in some cancer cell lines, however, more investigations are required to unravel the underlying mechanisms involved. Conclusions: The modern evidences of treating cancer with Huanglian and berberine have a strong linkage with traditional concept and rules of using Huanglian in CM practice. As anticancer candidates with low toxicity, berberine and its altered structure, as well as Huanglian and its formulae, will attract scientists to pursue the potential anticancer effects and the mechanisms by using technologies of genomics, proteomics and other advanced approaches. On the other hand, relatively few in vivo studies have been conducted on anticancer effects of Huanglian and berberine. The clinical application of berberine or Huanglian as novel cancer therapeutic agents requires in vivo validations and further investigations of their anticancer mechanisms. © 2009 Elsevier Ireland Ltd. All rights reserved.published_or_final_versio
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