202 research outputs found
Alliance free and alliance cover sets
A \emph{defensive} (\emph{offensive}) -\emph{alliance} in
is a set such that every in (in the boundary of ) has
at least more neighbors in than it has in . A set
is \emph{defensive} (\emph{offensive}) -\emph{alliance free,}
if for all defensive (offensive) -alliance , ,
i.e., does not contain any defensive (offensive) -alliance as a subset.
A set is a \emph{defensive} (\emph{offensive})
-\emph{alliance cover}, if for all defensive (offensive) -alliance ,
, i.e., contains at least one vertex from each
defensive (offensive) -alliance of . In this paper we show several
mathematical properties of defensive (offensive) -alliance free sets and
defensive (offensive) -alliance cover sets, including tight bounds on the
cardinality of defensive (offensive) -alliance free (cover) sets
Recommended from our members
Investigation of finger reflectance photoplethysmography in volunteers undergoing a local sympathetic stimulation
Optical sensors used in clinical applications have gained great popularity over the last few decades, especially the photoplethysmographic (PPG) technique used in estimating arterial blood oxygen saturation in the well-known medical devices called pulse oximeters. In this study we investigate the photoplethysmogram further in an effort to understand its origin better, as there is a significant void in the current knowledge on the PPG quantitative measurement. The photoplethysmographic signal provides a heart rhythm pulsating AC component, and a non-pulsating DC component. The signal is commonly believed to originate from tissue volume changes only and hasn't been investigated intensively. This in vivo study examines the source of the PPG signal in relation to pulse amplitude and pulse rhythm while volunteers undergo a right hand ice immersion. It was found that the PPG signal is sensitive in detecting the sympathetic stimulation which corresponds to volumetric and heart rate changes. During the immersion, AC pulse amplitudes (PA) from both hands decreased significantly, while DC levels increased significantly in the right hand and non-significantly in the left hand. Also, a significant decrease in the pulse repetition time (PRT) was observed. Using blood pressure-flow theories, these results suggest that there are possibly other factors in the blood flow regulation that alter the blood optical density which contributes to the detected signal. Further studies need to investigate PPGs in relation to blood optical density and the dynamics of the pulsatile flow effects besides volumetric changes. Such investigations might explore further applications of the PPG in medicine
Recommended from our members
In vivo investigation of ear canal pulse oximetry during hypothermia
Pulse oximeters rely on the technique of photoplethysmography (PPG) to estimate arterial oxygen saturation (SpO(Formula presented.)). In conditions of poor peripheral perfusion such as hypotension, hypothermia, and vasoconstriction, the PPG signals detected are often weak and noisy, or in some cases unobtainable. Hence, pulse oximeters produce erroneous SpO(Formula presented.) readings in these circumstances. The problem arises as most commercial pulse oximeter probes are designed to be attached to peripheral sites such as the finger or toe, which are easily affected by vasoconstriction. In order to overcome this problem, the ear canal was investigated as an alternative site for measuring reliable SpO(Formula presented.) on the hypothesis that blood flow to this central site is preferentially preserved. A novel miniature ear canal PPG sensor was developed along with a state of the art PPG processing unit to investigate PPG measurements from the bottom surface of the ear canal. An in vivo study was carried out in 15 healthy volunteers to validate the developed technology. In this comparative study, red and infrared PPGs were acquired from the ear canal and the finger of the volunteers, whilst they were undergoing artificially induced hypothermia by means of cold exposure (10 (Formula presented.)C). Normalised Pulse Amplitude (NPA) and SpO(Formula presented.) was calculated from the PPG signals acquired from the ear canal and the finger. Good quality baseline PPG signals with high signal-to-noise ratio were obtained from both the PPG sensors. During cold exposure, significant differences were observed in the NPA of the finger PPGs. The mean NPA of the red and infrared PPGs from the finger have dropped by >80%. Contrary to the finger, the mean NPA of red and infrared ear canal PPGs had dropped only by 0.2 and 13% respectively. The SpO(Formula presented.)s estimated from the finger sensor have dropped below 90% in five volunteers (failure) by the end of the cold exposure. The ear canal sensor, on the other hand, had only failed in one volunteer. These results strongly suggest that the ear canal may be used as a suitable alternative site for monitoring PPGs and arterial blood oxygen saturation at times were peripheral perfusion is compromised
NASCaps: A Framework for Neural Architecture Search to Optimize the Accuracy and Hardware Efficiency of Convolutional Capsule Networks
Deep Neural Networks (DNNs) have made significant improvements to reach the
desired accuracy to be employed in a wide variety of Machine Learning (ML)
applications. Recently the Google Brain's team demonstrated the ability of
Capsule Networks (CapsNets) to encode and learn spatial correlations between
different input features, thereby obtaining superior learning capabilities
compared to traditional (i.e., non-capsule based) DNNs. However, designing
CapsNets using conventional methods is a tedious job and incurs significant
training effort. Recent studies have shown that powerful methods to
automatically select the best/optimal DNN model configuration for a given set
of applications and a training dataset are based on the Neural Architecture
Search (NAS) algorithms. Moreover, due to their extreme computational and
memory requirements, DNNs are employed using the specialized hardware
accelerators in IoT-Edge/CPS devices. In this paper, we propose NASCaps, an
automated framework for the hardware-aware NAS of different types of DNNs,
covering both traditional convolutional DNNs and CapsNets. We study the
efficacy of deploying a multi-objective Genetic Algorithm (e.g., based on the
NSGA-II algorithm). The proposed framework can jointly optimize the network
accuracy and the corresponding hardware efficiency, expressed in terms of
energy, memory, and latency of a given hardware accelerator executing the DNN
inference. Besides supporting the traditional DNN layers, our framework is the
first to model and supports the specialized capsule layers and dynamic routing
in the NAS-flow. We evaluate our framework on different datasets, generating
different network configurations, and demonstrate the tradeoffs between the
different output metrics. We will open-source the complete framework and
configurations of the Pareto-optimal architectures at
https://github.com/ehw-fit/nascaps.Comment: To appear at the IEEE/ACM International Conference on Computer-Aided
Design (ICCAD '20), November 2-5, 2020, Virtual Event, US
Monitoring and evaluation of irrigation and drainage facilities for pilot distributaries in Sindh Province, Pakistan. Volume 4 - Heran Distributary, Sanghar District
Irrigation management / Monitoring / Evaluation / Irrigation canals / Distributary canals / Drainage / Irrigation practices / Water delivery / Watercourses / Maintenance / Water table / Groundwater / Water quality / Pakistan / Sindh Province / Sanghar District / Heran Distributary
A comparative study to evaluate the effects of antibiotics, plant extracts and fluoride-based toothpaste on the oral pathogens isolated from patients with gum diseases in Pakistan
Oral diseases caused by various microorganisms are common around the world. Scientific research has now been focusing on novel medicines to overcome bacterial resistance and antibiotics side effects; therefore, the current study was designed to assess the efficacy of certain antibiotics, toothpaste, and medicinal plant extracts (Ajuga bracteosa and Curcuma longa) versus the bacterial pathogens isolated from the human oral cavity. A total of 130 samples were collected from Khyber Teaching Hospital Peshawar, Pakistan, among those 27 species isolated, and eight bacterial species were identified from the samples. Among all the bacterial species, Staphylococcus aureus (29.62%) and Proteus mirabilis (22.2%) were found to be more prevalent oral pathogens. In comparison, the least pervasive microbes were Proteus vulgaris, Shigella sonnei, Escherichia coli and Aeromonas hydrophila. The study also suggested that dental problems were more prevalent in males (41-50 years of age) than females. Among the eight antibiotics used in the study, the most promising results were shown by Foxicillin against A. hydrophila. The survey of TP1 revealed that it showed more potent antagonist activity against Proteus vulgaris as compared TP2 and TP3 that might be due to the high content of fluoride. The Curcuma longa showed more significant activity than Ajuga bracteosa (Stem, leaves and root) extracts. The data obtained through this study revealed that antibiotics were more effective for oral bacterial pathogens than toothpaste and plant extracts which showed moderate and low activity, respectively. Therefore, it is suggested that the active compounds in individual medicinal plants like Curcuma longa and Ajuga bracteosa could replace the antibiotics when used in daily routine as tooth cleansers or mouth rinses
Changing presentation of prostate cancer in a UK population--10 year trends in prostate cancer risk profiles in the East of England.
BACKGROUND: Prostate cancer incidence is rising in the United Kingdom but there is little data on whether the disease profile is changing. To address this, we interrogated a regional cancer registry for temporal changes in presenting disease characteristics. METHODS: Prostate cancers diagnosed from 2000 to 2010 in the Anglian Cancer Network (n=21,044) were analysed. Risk groups (localised disease) were assigned based on NICE criteria. Age standardised incidence rates (IRs) were compared between 2000-2005 and 2006-2010 and plotted for yearly trends. RESULTS: Over the decade, overall IR increased significantly (P<0.00001), whereas metastasis rates fell (P<0.0007). For localised disease, IR across all risk groups also increased but at different rates (P<0.00001). The most striking change was a three-fold increase in intermediate-risk cancers. Increased IR was evident across all PSA and stage ranges but with no upward PSA or stage shift. In contrast, IR of histological diagnosis of low-grade cancers fell over the decade, whereas intermediate and high-grade diagnosis increased significantly (P<0.00001). CONCLUSION: This study suggests evidence of a significant upward migration in intermediate and high-grade histological diagnosis over the decade. This is most likely to be due to a change in histological reporting of diagnostic prostate biopsies. On the basis of this data, increasing proportions of newly diagnosed cancers will be considered eligible for radical treatment, which will have an impact on health resource planning and provision
A phenomenographic approach to the effect of emotions on the information behaviour of doctoral students: A narrative inquiry
© Springer Nature Switzerland AG 2020. This article is to examine how emotions affect the doctoral student’s journey by analyzing diverse aspects of the information behaviour that emerged from their narratives through a phenomenographic perspective. Narratives are a rational way of communication that focuses on how people perceive different phenomena regarding themselves, their inner thoughts, their states of mind, and how it affects their lifeworld’s. This phenomenographic study employs interview data from 36 doctoral students. The data collected from the narratives were studied drawing from the variation theory and iterative data analysis resulted in categories of doctoral student experiences and their emotional journey. The holistic phase of the thematic analysis revealed a relatively balanced interplay of positive and negative emotions. The rich data obtained in the phenomenographic approach exposed significant links between participants’ heightened emotions in five common themes during looking for information, their interactions with key individuals (supervisors and peer) and situations in their doctoral lives. Whilst this paper focuses on the approach taken to explore the narratives, recommendations are made based on the findings and to further explore the information-seeking behaviour patterns of doctoral students
Positive deviance as a novel tool in malaria control and elimination: methodology, qualitative assessment and future potential
Fast mode decision based on human noticeable luminance difference and rate distortion cost for H.264/AVC
- …