3,627 research outputs found
cAMP/Protein Kinase A activates Cystic Fibrosis Transmembrane Conductance Regulator for ATP release from rat skeletal muscle during low pH or contractions
published_or_final_versio
A model-based approach to recovering the structure of a plant from images
We present a method for recovering the structure of a plant directly from a
small set of widely-spaced images. Structure recovery is more complex than
shape estimation, but the resulting structure estimate is more closely related
to phenotype than is a 3D geometric model. The method we propose is applicable
to a wide variety of plants, but is demonstrated on wheat. Wheat is made up of
thin elements with few identifiable features, making it difficult to analyse
using standard feature matching techniques. Our method instead analyses the
structure of plants using only their silhouettes. We employ a generate-and-test
method, using a database of manually modelled leaves and a model for their
composition to synthesise plausible plant structures which are evaluated
against the images. The method is capable of efficiently recovering accurate
estimates of plant structure in a wide variety of imaging scenarios, with no
manual intervention
Antihypertensive drug class and dyslipidemia: risk association among Chinese patients with uncomplicated hypertension
Factors associated with dyslipidemia in Chinese patients with uncomplicated hypertension were investigated in 1,139 patients newly prescribed a single antihypertensive drug in the public primary healthcare setting in Hong Kong, where their fasting lipid profiles were measured 4 to 16 weeks after the first prescription. Multivariate logistic regression showed that thiazide users were more likely (OR 3.67, 95% C.I. 1.13, 11.88, p=0.030) to have adverse (> 6.2mmol/l) total cholesterol (TC) compared with drugs acting on the renin angiotensin system (RAS), but the absolute difference in mean TC between thiazide users and all patients was small ( 0.14 mmol/l), while advanced age and male gender were also associated with some aspects of dyslipidemia. Clinicians should be aware of the increased risk of dyslipidemia in these groups, but the mild dyslipidemic profile associated with thiazides should not in itself deter its use as a possible first-line antihypertensive agent among Chinese patients
The association of pulmonary function with carotid atherosclerosis in older Chinese: Guangzhou Biobank Cohort Study-CVD Subcohort
postprin
Wide Area Measuring System Signals Based Nonlinear Robust Adaptive DC Power Modulation Controller in AC/DC Interconnected Power System
The robust adaptive control law is proposed for a HVDC power modulation controller of the interconnected AC/DC power system. Based on the design idea of driving the center of inertia (COI) of different areas to a stable equilibrium point, the proposed controller is applied to damp inter-area oscillation of interconnected AC/ DC system using global signals of a wide area measuring system (WAMS). Designed by the back-stepping method, the robust adaptive control law is adaptive to the unknown parameters and is robust to model error, disturbances and different equilibrium points. Computer results show that the controller proposed is obviously superior to the conventional DC power modulation controller in damping inter-area oscillation and enhancing the power transfer limit. In addition, its performance can well adapt to the change of the equilibrium point.
設計了應用于交直流互聯電力系統的直流功率調制的非線性魯棒自適應控制器。該控制器基于驅動各互聯區域電網的慣量中心至統一平衡點的設計思想,采用廣域測量系統的全局信號,用以阻尼交直流互聯系統的區域間功率振蕩。采用反步法設計的自適應魯棒控制規律使控制器對未知參數具有自適應性,對模型誤差、擾動和平衡點變化具有較強的魯棒性。仿真結果表明,與傳統的線性直流功率調制控制器相比,該控制器對聯絡線的功率振蕩具有優良的阻尼性能,可顯著提高輸電極限,而且能很好地適應運行點的變化。link_to_OA_fulltex
Analysis of radiation-induced cell death in head and neck squamous cell carcinoma and rat liver maintained in microfluidic devices
Objective The aim of this study was to investigate how head and neck squamous cell carcinoma (HNSCC) tissue biopsies maintained in a pseudo in vivo environment within a bespoke microfluidic device respond to radiation treatment. Study Design Feasibility study. Setting Tertiary referral center. Subjects and Methods Thirty-five patients with HNSCC were recruited, and liver tissue from 5 Wistar rats was obtained. A microfluidic device was used to maintain the tissue biopsy samples in a viable state. Rat liver was used to optimize the methodology. HNSCC was obtained from patients with T1-T3 laryngeal or oropharyngeal SCC; N1-N2 metastatic cervical lymph nodes were also obtained. Irradiation consisted of single doses of between 2 Gy and 40 Gy and a fractionated course of 5×2 Gy. Cell death was assessed in the tissue effluent using the soluble markers lactate dehydrogenase (LDH) and cytochrome c and in the tissue by immunohistochemical detection of cleaved cytokeratin18 (M30 antibody). Results A significant surge in LDH release was demonstrated in the rat liver after a single dose of 20 Gy; in HNSCC, it was seen after 40 Gy compared with the control. There was no significant difference in cytochrome c release after 5 Gy or 10 Gy. M30 demonstrated a dose-dependent increase in apoptotic index for a given increase in single-dose radiotherapy. There was a significant increase in apoptotic index between 1×2 Gy and 5×2 Gy. Conclusion M30 is a superior method compared with soluble markers in detecting low-dose radiation-induced cell death. This microfluidic technique can be used to assess radiation-induced cell death in HNSCC and therefore has the potential to be used to predict radiation response
Effects of different management practices on the soil-water balance and crop yield for improved dryland farming in the Chinese Loess Plateau
Experimental measurement-based quantum computing beyond the cluster-state model
The paradigm of measurement-based quantum computation opens new experimental
avenues to realize a quantum computer and deepens our understanding of quantum
physics. Measurement-based quantum computation starts from a highly entangled
universal resource state. For years, clusters states have been the only known
universal resources. Surprisingly, a novel framework namely quantum computation
in correlation space has opened new routes to implement measurement-based
quantum computation based on quantum states possessing entanglement properties
different from cluster states. Here we report an experimental demonstration of
every building block of such a model. With a four-qubit and a six-qubit state
as distinct from cluster states, we have realized a universal set of
single-qubit rotations, two-qubit entangling gates and further Deutsch's
algorithm. Besides being of fundamental interest, our experiment proves
in-principle the feasibility of universal measurement-based quantum computation
without using cluster states, which represents a new approach towards the
realization of a quantum computer.Comment: 26 pages, final version, comments welcom
Zero Sound in Effective Holographic Theories
We investigate zero sound in -dimensional effective holographic theories,
whose action is given by Einstein-Maxwell-Dilaton terms. The bulk spacetimes
include both zero temperature backgrounds with anisotropic scaling symmetry and
their near-extremal counterparts obtained in 1006.2124 [hep-th], while the
massless charge carriers are described by probe D-branes. We discuss
thermodynamics of the probe D-branes analytically. In particular, we clarify
the conditions under which the specific heat is linear in the temperature,
which is a characteristic feature of Fermi liquids. We also compute the
retarded Green's functions in the limit of low frequency and low momentum and
find quasi-particle excitations in certain regime of the parameters. The
retarded Green's functions are plotted at specific values of parameters in
, where the specific heat is linear in the temperature and the
quasi-particle excitation exists. We also calculate the AC conductivity in
-dimensions as a by-product.Comment: 29 pages, 1 figur
A Convolutional Approach to Vertebrae Detection and Labelling in Whole Spine MRI
We propose a novel convolutional method for the detection and identification
of vertebrae in whole spine MRIs. This involves using a learnt vector field to
group detected vertebrae corners together into individual vertebral bodies and
convolutional image-to-image translation followed by beam search to label
vertebral levels in a self-consistent manner. The method can be applied without
modification to lumbar, cervical and thoracic-only scans across a range of
different MR sequences. The resulting system achieves 98.1% detection rate and
96.5% identification rate on a challenging clinical dataset of whole spine
scans and matches or exceeds the performance of previous systems on lumbar-only
scans. Finally, we demonstrate the clinical applicability of this method, using
it for automated scoliosis detection in both lumbar and whole spine MR scans.Comment: Accepted full paper to Medical Image Computing and Computer Assisted
Intervention 2020. 11 pages plus appendi
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