31 research outputs found
Management of client requirements for design and build projects in the construction industry of Hong Kong
No full textAuthor name used in this publication: Patrick T.I. Lam2010-2011 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishedGreen (AAM
Tang Bi formula alleviates diabetic sciatic neuropathy via AMPK/PGC-1α/MFN2 pathway activation
No full textAbstract Diabetic peripheral neuropathy (DPN) is one of the most common chronic complications of diabetes mellitus, which affects various regions of the nervous system. Tang Bi formula (TBF) has been proven effective for DPN, while the underlying mechanism remains unclarified. This study aimed to clarifiy the neurprotective mechanism of TBF intervention in DPN through animal and cell models. UHPLC/QTOF-MS and network pharmacology analysis were utilized to identify the bioactive components and potential targets of TBF. DPN models were established in rats and Schwann cells to evaluate the therapeutic effects of TBF. In the DPN rats, body weight, fasting blood glucose, mechanical withdrawal threshold (MWT), paw withdrawal latency (PWL), sciatic motor nerve conduction velocity (MNCV), and sciatic nerve blood flow were measured. Pathological sections of the sciatic nerve (SN) were also examined. In vitro experiments, the Schwann cells (SCs) were cultured in a medium containing 30 mM glucose and treated with TBF for 48 h. Cell viability was assessed using the CCK-8 assay. The degree of apoptosis was evaluated by flow cytometry. The mitochondrial membrane potential was determined using JC—1 staining, and the generation of ROS was measured using DCFH—DA staining. Moreover, the expression levels of proteins related to the AMPK-PGC-1α-MFN2 pathway in the SN and SCs were detected. A total of 11 bioactive components of TBF were identified through UHPLC/QTOF-MS and network pharmacology analysis. In vivo experiments, MWT and PWL were decreased in DPN rats, which were restored after TBF administered daily for 12 weeks, TBF significantly attenuated thermal hyperalgesia and mechanical allodynia, and improved nerve conduction velocities. Further histopathological observations indicated that treatment with TBF promoted the regeneration of the myelin sheath of the SN, increased the density of intraepidermal nerve fibers, effectively improved distal microcirculation disorders, and alleviated demyelination and axonal degeneration. In vitro experiments were conducted to evaluate the protective effect of TBF on high-glucose-induced dysfunction of SCs. The data showed that treatment with TBF significantly inhibited the apoptosis of SCs. Meanwhile, TBF exhibited apparent antioxidant capacity, reducing the accumulation of intracellular ROS, and ameliorating mitochondrial dysfunction. Western blot analysis revealed that TBF activated the AMPK-PGC -1α-MFN2 pathway and upregulated the protein expressions of p-AMPK (Thr172), PGC-1α, and MFN2, suggesting that the neuroprotective effect of TBF was associated with the activation of this pathway. TBF ameliorated DPN by rectifying mitochondrial dynamic imbalance and modulating the activation of the AMPK-PGC-1α-MFN2 pathway. This, in turn, promoted neurogenesis and alleviated peripheral nerve lesions. Thus, this study demonstrated the therapeutic potential of TBF for DPN
Compiled Code Simulation of Analog and Mixed-Signal Systems Using Piecewise Linear Modeling of Nonlinear Parameters
No full textThis paper presents a method for fast time-domain simulation of analog systems with nonlinear parameters. Specifically, the paper focuses on £¥ ¤ analog-to-digital converters (ADC). The method creates compiled-code simulators based on symbolic analysis. Code is optimized using loop invariant elimination and constant folding. Circuits are described as structural macromodels. Non-linear parameters are expressedusing piecewise linear (PWL) models. The paper presents a technique for automatically creating PWL models through model extraction from trained neural networks. As compared to existing behavioral simulation methods for £¥ ¤ ADC, this technique is more automated and accurate. In our experiments, compiled-code simulation was significantly faster than numerical simulation.
Pressing Questions for the Philosophical Life in a Time of Crisis
No full text2020, the year the coronavirus pandemic spread globally, marked the twenty-fifth year since the publication of Pierre Hadot’s work Philosophy as a Way of Life (translated by co-author Michael Chase). In that time, what began as the research specialization of just a few scholars has become a growing area of philosophical and metaphilosophical inquiry, bringing together researchers from around the globe. Hadot’s key ideas of spiritual exercises, and the very idea of PWL, have been applied to a host of individual thinkers from across the history of philosophy: from the Hellenistic and Roman-era philosophers of direct concern to Hadot, through renaissance thinkers like Petrarch, Lipsius, Montaigne, Descartes, or Bacon, into nineteenth-century thinkers led by Schopenhauer, Kierkegaard, and Nietzsche.In more recent years, more global reflections on the “very idea” of PWL have begun to emerge, as well as dedicated journal editions. In these more recent PWL studies, some of the manifold research questions have begun to be explored, which were opened up by the studies of Pierre and Ilsetraut Hadot, as well as its reception in Michel Foucault’s later work. What implications, after all, does understanding the history of PWL, and the predominance of this metaphilosophical conception in the history of Western thought, have for how we understand the practice(s) of philosophy today? Does recovering the alternative understandings of philosophy as a practice in history necessarily lead to a criticism of contemporary, solely academic or theoretical modes of philosophizing, or is the idea of PWL one which has only historiographical force
Temporal Effects of Message Congruency on Attention to and Recall of Pictorial Health Warning Labels on Cigarette Packages
No full textAbstract
Objectives
Recent research has shown that message congruency is beneficial to recall of pictorial health warning label (PWL) content after initial exposure. Despite less attention to the text warning, smokers exposed to congruent PWLs were more likely to recall the text and the message. This study aimed to replicate these findings and to examine whether congruency also affects recall after multiple exposures over time.
Methods
A total of 320 daily smokers (39.7% female; cigarettes/day: M = 15.31, SD = 7.15) were randomized to one congruent or incongruent PWL and attended 4 laboratory sessions over 10 days. During each session, eye movements were recorded while viewing the PWL and open-ended recall of label content was assessed after exposure.
Results
Smokers who were exposed to a congruent PWL were more likely to recall the text (p = .01) and the message (p = .02) and less likely to recall the image (p = .003) of the PWL after initial exposure. By day 4, incongruent PWLs were recalled equally well as congruent PWLs. Independent of condition, image recall was initially high and remained high whereas text and message recall was relatively low initially but increased over time. It was not until day 7 that about 80% of text and message recall was observed.
Conclusions
Even when exposed to the same PWL over time, smokers require multiple exposures to recall the text and the message of a PWL. More research on the effects of congruency in the natural environment, where smokers are exposed to multiple PWLs, is needed.
Implications
The findings of this study, and of previous work showing that message congruency in PWLs is beneficial to initial recall of PWL content, could potentially help to address legal challenges regarding the implementation of PWLs in the United States. Factually correct text warnings have been uncontested on US cigarettes packages since 1966. Congruent PWLs simply provide a means to visually support the same information as the existing text using a medium that better garners attention to the health information. Investigating and understanding longer-term effects of congruency are important and can empirically inform future warning label development, both in the United States via the Family Smoking Prevention and Tobacco Control Act, and via other governing bodies.
</jats:sec
Electroacupuncture inhibition of hyperalgesia in an inflammatory pain rat model: Involvement of distinct spinal serotonin and norepinephrine receptor subtypes
No full textBackground Although acupuncture analgesia is well documented, its mechanisms have not been thoroughly clarified. We previously showed that electroacupuncture (EA) activates supraspinal serotonin- and norepinephrine-containing neurones that project to the spinal cord. This study investigates the involvement of spinal alpha(2)-adrenoceptors (α2-ARs) and 5-hydroxytryptamine (serotonin) receptors (5-HTRs) in EA effects on an inflammatory pain rat model.MethodsInflammatory hyperalgesia was induced by injecting complete Freund's adjuvant (CFA, 0.08 ml) into the plantar surface of one hind paw and assessed by paw withdrawal latency (PWL) to a noxious thermal stimulus. The selective α2a-AR antagonist BRL-44408, α2b-AR antagonist imiloxan hydrochloride, 5-HT2B receptor (5-HT2BR) antagonist SB204741, 5-HT3R antagonist LY278584, or 5-HT1AR antagonists NAN-190 hydrobromide, or WAY-100635 were intrathecally administered 20 min before EA or sham EA, which was given 2 h post-CFA at acupoint GB30.ResultsEA significantly increased PWL compared with sham [7.20 (0.46) vs 5.20 (0.43) s]. Pretreatment with α2a-AR [5.35 (0.45) s] or 5-HT1AR [5.22 (0.38) s] antagonists blocked EA-produced anti-hyperalgesia; α2b-AR, 5-HT2BR, and 5-HT3R antagonist pretreatment did not. Sham plus these antagonists did not significantly change PWL compared with sham plus vehicle, indicating that the antagonists had little effect on PWL. Immunohistochemical staining demonstrated that α2a-ARs are on primary afferents and 5-HT1ARs are localized in N-methyl-d-aspartic acid (NMDA) subunit NR1-containing neurones in the spinal dorsal horn.ConclusionsThe data show that α2a-ARs and 5-HT1ARs are involved in the EA inhibition of inflammatory pain and that the NMDA receptors are involved in EA action. © The Author [2012]. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissionsoup.com2012 © © The Author [2012]. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved.link_to_subscribed_fulltex
Alternasi argumen Inti Dalam Bahasa Jawa Dialek Surabaya
No full textBahasa Jawa sebagai salah sanl bahasa daerah yang besar di Indonesia
sesWlgguhnya sudah cukup banyak ditelaah oleh para ahli bahasa. Aspek yang di
bahas pWl cukup merata, mencakup berbagai tataran. yakni fonologi, morfologi,
sintaksis. dan semantik. Akan tetapi, para ahli tersebut dalam penelitiannya pada
umumnya menggunakan teorl tradisional (struktural) yang dewasa ini sudah mulai
banyak ditinggalkan orwig karcna bcrbagai kelcmahan.
Penelitian ini mencoba mengkaji satu aspek sintaksis bahasa Jawa (altemasi
argumen inti) dengan menggWlakan perspektif teori yang berbeda dengan para ahli
terdahuill. Teori yang dimaksud adalah teorl tata bahasa leksikal-fungsional atau
Lexical Funclional-Grammar (LFG). Tujuan yang hendak dicapai adalah Wltuk
mendapatkan gambaran yang komprehcnsif ten tang seluk-beluk altcmasi argu":lcn
inti ballasa Jawa, terutama mengenai (a) propeni argwnen inti dan noninti, (b)
mekanisme altemasi argumen inti itu terjadi, dan (c) altemasi argumen inti tersebut
dilihat dari perspektif lexical mapping theory (LMT)
Frequency behavior of saturated nonlinear function series based on opamps
No full text[EN]: In multiscroll chaotic circuit design based on active devices, piece-wise linear (PWL) approaches are often used to model the behavior of nonlinear functions, thereby that the behavior of a chaotic system can be forecasted through numerical simulations. However, although PWL models are relatively easy to build, they do not include any information related on the performance parameters of the active devices to be used. This a serious shortcoming, since PWL-models introduces a level of inaccuracy into a numerical analysis which is more evident when numerical simulations and experimental results are compared. These differences are more pronounced when the chaotic waveforms to be generated are pushed to operate at high-frequency. This paper introduces experimental results on the frequency behavior of a nonlinear function called saturated nonlinear function series based on operational amplifiers. These new results are key not only on the automatic synthesis of chaotic attractors and on the synchronization schemes used in secure communication systems based on chaos, but also on the metrics used to evaluate the complexity of a chaotic system. A mathematical model to characterize the behavior of the nonlinear function is also derived, showing a better accuracy compared with the PWL approach. The theoretical derivations and related results are experimentally validated through implementations from commercially available devices.[ES]: En el diseño de circuitos cáoticos con múltiples enrollamientos basado en dispositivos activos, el comportamiento de las funciones no lineales es representado por aproximaciones lineales a trozos (PWL). Sin embargo, aunque modelos PWL son fáciles de construir, estos no incluyen ninguna información relacionada con los parámetros de desempeño de los dispositivos activos a ser usados. Este es un serio inconveniente, ya que modelos PWL introducen un nivel de inexactitud en un análisis numérico el cual llega a ser más evidente cuando las simulaciones numéricas son comparadas con resultados experimentales. Estas diferencias son más pronunciadas cuando las formas de onda cáoticas a ser generadas son empujadas a operar en alta frecuencia. Este artículo introduce resultados experimentales sobre el comportamiento en frecuencia de la función no lineal llamada serie de funciones saturadas las cuales son diseñadas con amplificadores operacionales. Los
nuevos resultados son clave no solamente en la síntesis automática de atractores cáoticos y en los esquemas de sincronización usados en
los sistemas de comunicación basados en caos, pero también en las métricas usadas para evaluar la complejidad de un sistema cáotico. Un modelo analítico para caracterizar el comportamiento de la función no lineal es derivado y este es más exacto que el modelo PWL. Los resultados teóricos son validados con resultados experimentales a través del uso de dispositivos comerciales.This work has been supported in part by the projects: UAT-121AD-R and CACyPI-UATx-2013 both funded by Autonomous University of Tlaxcala, Mexico. Author J.M.L. thanks the support of the JAE-Doc program of CSIC, cofunded by the E.S.F.Peer Reviewe
Investigation of propeller characteristics at low Reynolds number with an angle of attack: A computational aeroacoustic study
No full textAdvancements in technology have made commercial unmanned aerial vehicles reliable and readily available, leading to an exponential rise in their market demand over the past few years. COVID-19 has further accelerated this growth through an increase in demand for contact-less delivery and crowd monitoring systems. However, despite these favorable conditions, their limited range, perceived threat, and concerns about noise pollution in urban environments have prevented them from being widely accepted by society. A recent study by NASA found that people perceive UAV noise to be more annoying than cars, and trucks at a similar sound pressure level, which highlights the need to understand the acoustic characteristic of these aircraft. These UAVs are generally powered by electric motors, making their propellers the most dominant source of noise. In the past, researchers have conducted several studies to understand and characterize the noise produced by aircraft propellers. However, these studies were limited to high Reynolds (>1,000,000) and Mach number operations for large commercial aircraft, creating a significant gap in the understanding of the aerodynamic and acoustic characteristics of propellers operating at low Reynolds (<200,000) and Mach number. This thesis aims to address the research gap by performing a high-fidelity computational simulation using Dassault Systèmes PowerFLOW®. The tool uses a lattice Boltzmann very large eddy simulation (LBM-VLES) based approach to compute the aerodynamic results and the Ffowcs-Williams and Hawkings (FWH) aeroacoustic analogy to calculate far-field acoustic values. The main objective of the thesis is: “To characterize and quantify the effect of non-axisymmetric inflow conditions on the aerodynamic and acoustic properties of propellers operating at low Reynolds numbers.” To meet the objective, a computational setup consisting of a twin-bladed propeller with a radius of 15 cm is designed in PowerFLOW®. The propeller is analyzed at 0º and 15º AoA, operating at 6000 RPM with a free stream velocity of 12 m/sec and the results validated against experimental data. Aerodynamic measurements and flow analysis revealed that the change in angle of attack (AoA) resulted in a 3.87% increase in the net thrust, and 1.16% increase in the net torque value of the propeller. Operating at an AoA, the propeller blade experiences asymmetric loading around the propeller plane, the loads fluctuate by 35% between the points of maximum and minimum loading. Further analysis of the propeller flow field is carried out by averaging the velocity field and performing a phase-locked analysis to visualize the vortex field. The analysis helps in understanding the effect of AoA on propeller wake and quantifies its a symmetric nature. Far-field acoustic data is acquired by two circular microphone arrays, with a polar angle resolution of 10º. The arrays are placed around the propeller plane and along the axial axis of the propeller. The change in AoA results in a 3 dB higher noise at an azimuthal angle (Ψ) of 90º and reduces by an equal magnitude at Ψ = 270º. The shift is attributed to the change in propeller tip Mach number and local blade AoA as a function of its azimuthal location and propeller AoA. Further analysis of the sound power level (PWL) produced by the propeller is carried out, showing a 1.5 dB increase in the PWL produced by the propeller blade at 15º AoA than 0º.Aerospace Engineerin
Group III mGluR8 negatively modulates TRP channels
No full textSeveral lines of evidence indicate group III metabotropic glutamate receptors (mGluRs) have systemic anti-hyperalgesic effects. We hypothesized this could occur through modulation of TRP channels on nociceptors. The following studies used a multifaceted approach to examine the interaction between group III mGluRs (mGluR8) and two TRP channels: TRPV1 and TRPA1. In the first study, we examined the interaction between group III mGluRs and TRPV1. Anatomical studies demonstrated that group III mGluR8 is expressed on cutaneous axons and is co-localized with TRPV1 in the dorsal root ganglia (DRG). In behavior studies, peripheral activation of group III mGluRs had no effect on paw withdrawal latency (PWL) to heat in naïve rats. However, local peripheral activation of group III mGluRs significantly attenuated capsaicin (CAP, TRPV1 agonist)-induced lifting/licking and reduced flinching behavior. Finally peripheral group III mGluR activation reversed forskolin (FSK)-induced heat sensitivity, suggesting that group III could modulate TRPV1 by down-regulating cAMP-PKA activity. In the second part of the study, we examined the interaction between group III mGluR8 and TRPA1. Ca2+ imaging studies demonstrated co-localization and functional coupling of TRPA1 and mGluR8, since DCPG (mGluR8 agonist) significantly reduced the number of mustard oil (MO, TRPA1 agonist) responsive cells. Behavioral studies demonstrated that peripheral DCPG reversed the MO-induced decrease in PWT. At the single fiber level, DCPG significantly attenuated MO-induced nociceptor activity and reversed the MO-induced decrease in mechanical threshold. Furthermore, DCPG significantly reduced the number of MO-induced mechanically sensitive fibers. Inhibition of PKA using RpCAMPS significantly reduced MO-induced calcium mobilization and there was a trend to reduce the number of MO-responsive cells. Taken together, these results show that group III mGluRs can negatively modulate TRPV1 and TRPA1 activity. Furthermore, it is likely that this modulation occurs at the level of the cAMP/PKA pathway. Additionally, these studies demonstrate that group III agonists may be effective in treatment of mechanical allodynia which can develop as a result of inflammation, nerve injury, chemotherapy or other disease states
