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1.
Sensors (Basel) ; 21(3)2021 Jan 25.
Article in English | MEDLINE | ID: mdl-33504117

ABSTRACT

Forest fires are undesirable situations with tremendous impacts on wildlife and people's lives. Reaching them quickly is essential to slowing down their expansion and putting them out in an effective manner. This work proposes an optimized distribution of fire stations in the province of Valencia (Spain) to minimize the impacts of forest fires. Using historical data about fires in the Valencia province, together with the location information about existing fire stations and municipalities, two different clustering techniques have been applied. Floyd-Warshall dynamic programming algorithm has been used to estimate the average times to reach fires among municipalities and fire stations in order to quantify the impacts of station relocation. The minimization was done approximately through k-means clustering. The outcomes with different numbers of clusters determined a predicted tradeoff between reducing the time and the cost of more stations. The results show that the proposed relocation of fire stations generally ensures faster arrival to the municipalities compared to the current disposition of fire stations. In addition, deployment costs associated with station relocation are also of paramount importance, so this factor was also taken into account in the proposed approach.

2.
Sensors (Basel) ; 20(9)2020 Apr 25.
Article in English | MEDLINE | ID: mdl-32344805

ABSTRACT

Vehicle platoons involve groups of vehicles travelling together at a constant inter-vehicle distance, with different common benefits such as increasing road efficiency and fuel saving. Vehicle platooning requires highly reliable wireless communications to keep the group structure and carry out coordinated maneuvers in a safe manner. Focusing on infrastructure-assisted cellular vehicle to anything (V2X) communications, the amount of control information to be exchanged between each platoon vehicle and the base station is a critical factor affecting the communication latency. This paper exploits the particular structure and characteristics of platooning to decrease the control information exchange necessary for the channel acquisition stage. More precisely, a scheme based on radio environment map (REM) reconstruction is proposed, where geo-localized received power values are available at only a subset of platoon vehicles, while large-scale channel parameters estimates for the rest of platoon members are provided through the application of spatial Ordinary Kriging (OK) interpolation. Distinctive features of the vehicle platooning use case are explored, such as the optimal patterns of vehicles within the platoon with available REM values for improving the quality of the reconstruction, the need for an accurate semivariogram modeling in OK, or the communication cost when establishing a centralized or a distributed architecture for achieving REM reconstruction. The evaluation results show that OK is able to reconstruct the REM in the platoon with acceptable mean squared estimation error, while reducing the control information for REM acquisition in up to 64% in the best-case scenario.


Subject(s)
Automobile Driving , Communication , Models, Theoretical , Spatial Analysis
3.
Sensors (Basel) ; 19(13)2019 Jul 08.
Article in English | MEDLINE | ID: mdl-31288378

ABSTRACT

Existing correlations between features extracted from Electroencephalography (EEG) signals and emotional aspects have motivated the development of a diversity of EEG-based affect detection methods. Both intra-subject and inter-subject approaches have been used in this context. Intra-subject approaches generally suffer from the small sample problem, and require the collection of exhaustive data for each new user before the detection system is usable. On the contrary, inter-subject models do not account for the personality and physiological influence of how the individual is feeling and expressing emotions. In this paper, we analyze both modeling approaches, using three public repositories. The results show that the subject's influence on the EEG signals is substantially higher than that of the emotion and hence it is necessary to account for the subject's influence on the EEG signals. To do this, we propose a data transformation that seamlessly integrates individual traits into an inter-subject approach, improving classification results.


Subject(s)
Electroencephalography/methods , Emotions/physiology , Models, Biological , Signal Processing, Computer-Assisted , Arousal/physiology , Data Analysis , Databases, Factual , Humans , Support Vector Machine
4.
J Biol Chem ; 294(3): 1059-1069, 2019 01 18.
Article in English | MEDLINE | ID: mdl-30459233

ABSTRACT

FoxO proteins are major targets of insulin action, and FoxO1 mediates the effects of insulin on hepatic glucose metabolism. We reported previously that serpinB1 is a liver-secreted factor (hepatokine) that promotes adaptive ß-cell proliferation in response to insulin resistance in the liver-specific insulin receptor knockout (LIRKO) mouse. Here we report that FoxO1 plays a critical role in promoting serpinB1 expression in hepatic insulin resistance in a non-cell-autonomous manner. Mice lacking both the insulin receptor and FoxO1 (LIRFKO) exhibit reduced ß-cell mass compared with LIRKO mice because of attenuation of ß-cell proliferation. Although hepatic expression of serpinB1 mRNA and protein levels was increased in LIRKO mice, both the mRNA and protein levels returned to control levels in LIRFKO mice. Furthermore, liver-specific expression of constitutively active FoxO1 in transgenic mice induced an increase in hepatic serpinB1 mRNA and protein levels in refed mice. Conversely, serpinB1 mRNA and protein levels were reduced in mice lacking FoxO proteins in the liver. ChIP studies demonstrated that FoxO1 binds to three distinct sites located ∼9 kb upstream of the serpinb1 gene in primary mouse hepatocytes and that this binding is enhanced in hepatocytes from LIRKO mice. However, adenoviral expression of WT or constitutively active FoxO1 and insulin treatment are sufficient to regulate other FoxO1 target genes (IGFBP-1 and PEPCK) but not serpinB1 expression in mouse primary hepatocytes. These results indicate that liver FoxO1 promotes serpinB1 expression in hepatic insulin resistance and that non-cell-autonomous factors contribute to FoxO1-dependent effects on serpinB1 expression in the liver.


Subject(s)
Forkhead Box Protein O1/metabolism , Gene Expression Regulation , Hepatocytes/metabolism , Liver/metabolism , Serpins/biosynthesis , Animals , Forkhead Box Protein O1/genetics , Hepatocytes/cytology , Insulin-Like Growth Factor Binding Protein 1/genetics , Insulin-Like Growth Factor Binding Protein 1/metabolism , Liver/cytology , Male , Mice , Mice, Transgenic , Phosphoenolpyruvate Carboxykinase (ATP)/genetics , Phosphoenolpyruvate Carboxykinase (ATP)/metabolism , Serpins/genetics
5.
Sensors (Basel) ; 16(10)2016 Sep 22.
Article in English | MEDLINE | ID: mdl-27669241

ABSTRACT

The use of massive multiple-input multiple-output (MIMO) techniques for communication at millimeter-Wave (mmW) frequency bands has become a key enabler to meet the data rate demands of the upcoming fifth generation (5G) cellular systems. In particular, analog and hybrid beamforming solutions are receiving increasing attention as less expensive and more power efficient alternatives to fully digital precoding schemes. Despite their proven good performance in simple setups, their suitability for realistic cellular systems with many interfering base stations and users is still unclear. Furthermore, the performance of massive MIMO beamforming and precoding methods are in practice also affected by practical limitations and hardware constraints. In this sense, this paper assesses the performance of digital precoding and analog beamforming in an urban cellular system with an accurate mmW channel model under both ideal and realistic assumptions. The results show that analog beamforming can reach the performance of fully digital maximum ratio transmission under line of sight conditions and with a sufficient number of parallel radio-frequency (RF) chains, especially when the practical limitations of outdated channel information and per antenna power constraints are considered. This work also shows the impact of the phase shifter errors and combiner losses introduced by real phase shifter and combiner implementations over analog beamforming, where the former ones have minor impact on the performance, while the latter ones determine the optimum number of RF chains to be used in practice.

6.
Pain ; 59(3): 395-403, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7708414

ABSTRACT

The present study tested the hypothesis that patients receiving epidural bupivacaine before surgery would require less morphine postoperatively and/or report less intense pain than patients receiving epidural bupivacaine after incision but before the end of surgery. Forty-two patients (ASA class I-III) scheduled for lower abdominal surgery were randomly assigned to 1 of 2 groups of equal size and prospectively studied using a double-blind, placebo-controlled crossover design. Epidural catheters were placed in the T12-L1 or L1-L2 interspaces pre-operatively, the position of the catheter was confirmed with 3% chloroprocaine with epinephrine 1:200,000, and sensory testing was carried out until levels had receded to below T12. Group 1 received 15 ml of 0.5% epidural bupivacaine injected 35 min before incision followed by 15 ml of epidural normal saline 30 min after incision. Group 2 received 15 ml of epidural normal saline injected 37 min before incision followed by 15 ml of 0.5% epidural bupivacaine 30 min after incision. General anaesthesia was induced with thiopental (4-6 mg/kg) and maintained with N2O/O2 and isoflurane. Paralysis was achieved with pancuronium (0.1 mg/kg). Opioids were not used as pre-medication or during surgery. Postoperative analgesia consisted of patient-controlled (PCA) intravenous morphine. Visual analogue pain scores (VAS) (at rest and after standardized mobilization) did not differ significantly between the 2 groups but McGill Pain Questionnaire (MPQ) pain ratings were significantly lower in group 1 at the 24 and 72 h assessments. Group 1 used significantly less morphine than did group 2 between 12 and 24 h after surgery.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Abdomen/surgery , Analgesia, Patient-Controlled , Anesthesia, Epidural , Morphine/therapeutic use , Pain, Postoperative/prevention & control , Anesthesia , Blood Glucose/metabolism , Bupivacaine/therapeutic use , Cross-Over Studies , Double-Blind Method , Humans , Hydrocortisone/blood , Middle Aged , Morphine/administration & dosage , Pain Measurement
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