119 research outputs found
Pavement Defect Classification and Localization Using Hybrid Weakly Supervised and Supervised Deep Learning and GIS
Automated detection of road defects has historically been challenging for the pavement management industry. As a result, new methods have been developed over the past few years to handle this issue. Most of these methods relied on supervised machine learning techniques, such as object detection and segmentation methods, which need a large, annotated image dataset to train their models. However, annotating pavement defects is difficult and time-consuming due to their ununiformed and complex shapes. To address this challenge, a hybrid pavement defect classification and localization framework using weakly supervised and supervised deep learning methods is proposed in this thesis. This framework has two steps: (1) A robust hierarchical two-level classifier that classifies the defects in images, and (2) A method for defect localization combining weakly supervised and supervised techniques. In the localization method, first, defects are primarily localized using a weakly supervised method (i.e. Class Activation Mapping (CAM)). Next, based on the results of the first classifiers, the defects are segmented from the localized patches obtained in the previous step. The feature maps extracted from the CAM method are used to train a segmentation network once (i.e. U-Net or Mask R-CNN) to localize and segment the defects in the images. Thus, the proposed framework combines the advantages of weakly supervised and supervised methods. The supervised modules in the framework are trained once and can be used for any new data without the need to train. In other words, to use our framework on new dataset only the classifiers should be fine-tuned. Furthermore, the proposed framework introduced an innovative method designed to calculate the maximum crack width in pixels within linear segmented defect patches, derived from the localization module of the proposed framework. This method is particularly advantageous as it provides critical information that can be further employed in the calculation of the Pavement Condition Index (PCI).
Additionally, the proposed method benefits from an asset management inspection system based on Geographic Information System (GIS) technology to prepare the dataset used in the training and testing. Thus, this advanced system serves a dual role within our framework. Firstly, it assists in the assembly and preparation of the dataset used in the model training process, providing a geographically organized collection of images and related data. Secondly, it plays a crucial role in the testing phase, offering a spatially accurate platform for evaluating the effectiveness of the model in real-world scenarios.
A dataset from Georgia State in the USA was used in the case study. The proposed framework obtained high precision of 97%, 88%, 92% and 97% for localizing the alligator, block, longitudinal and transverse cracks, respectively. Considering all factors, such as annotation cost, and performance on the test dataset, the proposed localization method outperforms the supervised localization methods, such as instance segmentation and object detection for localizing road pavement defect
Investigation into the Thermal Behavior and Loadability Characteristic of a YASA-AFPM Generator via an Improved 3-D Coupled Electromagnetic-Thermal Approach
The objective of this paper is to investigate the thermal behaviour and loadability characteristic of a yokeless and segmented armature axial-flux permanent-magnet (YASA-AFPM) generator, which uses an improved 3-D coupled electromagnetic-thermal approach. Firstly, a 1-kW YASA-AFPM generator is modelled and analysed by using the proposed approach; the transient and steady-state temperatures of different parts of the generator are determined. To improve the modelling accuracy, the information is exchanged between the thermal and electromagnetic models at each step of the co-simulation, considering both the accurate calculation of losses and the impacts of temperature rise on the temperature-dependent characteristics of the materials. Then, by using the proposed approach, the impact of the slot opening width and the turn number of stator segments on the generator loadability are investigated. After that, the experimental tests are performed. The results reveal the effectiveness and accuracy of the approach to predict the machine loadability and thermal behavior
Improving Profitability of a Color Production Line by Breaking Down Bottlenecks: A Computer Simulation Approach
Bottlenecks are one of the controversial issues in manufacturing companies.
Managers and designers attempt to manage this trouble to improve efficiency in
different ways. For example, expanding capacity is a prevalent solution to get
rid of bottlenecks. In this paper, a color production line is chosen, which
faces several challenges in its production line. This company attempts to
distinguish and diminish the bottlenecks in the production line. The objective
of this paper is to build a developed model of a production line to improve its
profitability by breaking down its bottlenecks. Besides, the optimum number of
operators with different utilizations is investigated in this paper.
Furthermore, we considered the construction of new quality control in the
station, which is the most time-wasting operation in the production line. The
current study aims to apply computer simulation to examine the production line
bottlenecks. In doing so, arena 14.00 software is used. Then the results are
analyzed, and several managerial implications are presented.Comment: 10 page
Cellular Underwater Wireless Optical CDMA Network: Potentials and Challenges
Underwater wireless optical communications is an emerging solution to the
expanding demand for broadband links in oceans and seas. In this paper, a
cellular underwater wireless optical code division multiple-access (UW-OCDMA)
network is proposed to provide broadband links for commercial and military
applications. The optical orthogonal codes (OOC) are employed as signature
codes of underwater mobile users. Fundamental key aspects of the network such
as its backhaul architecture, its potential applications and its design
challenges are presented. In particular, the proposed network is used as
infrastructure of centralized, decentralized and relay-assisted underwater
sensor networks for high-speed real-time monitoring. Furthermore, a promising
underwater localization and positioning scheme based on this cellular network
is presented. Finally, probable design challenges such as cell edge coverage,
blockage avoidance, power control and increasing the network capacity are
addressed.Comment: 11 pages, 10 figure
The Effect of Individual, Social and Economic Factors on Villagers Participation in Watershed Projects in MianKouh Watershed, Yazd
This paper is accounted as a descriptive field survey with respect to the control degree, data collection and finding generalization. Research population consists of all the residents of MianKouh in Yazd province. The data collection tool is a questionnaire which involves seven sections such as occupational and personal specifications of respondents, cultural and social elements, participation levels, economic factors, social relationships, information and promotion sources and individual participation rate in Watershed Projects (considered as the dependent variable). Questionnaire validity has been confirmed by a group of agricultural extension and Cronbach alpha coefficient. Results have shown that participation rate of respondents is low and moderate in all the evaluated aspects involving cultural and social elements, participation levels, economic factors, social relationships and information sources. Undoubtedly, if such circumstances continue, sustainable management of watershed projects is more likely to encounter some difficulties and impose high costs on the government in order to implement and expand the plans and projects while in recent years, there have been such conditions in the desired region. Considering the results of regression analysis, it is found that the highest variable value can be related to the variable of attendance in watershed courses and promotion workshops, which was entered in the analysis in the first step. Also, the operation has been stopped after the input of second variable that is meeting with farmers who implemented the watershed projects in the village. In total, these two variables could explain almost 35% variations of individual participation in watershed projects considered as a dependent variable
Multilevel Measurement of Acetabular Version Using 3-D CT-generated Models: Implications for Hip Preservation Surgery
The Effect of Adding Ondansetron and Metoclopramide to Intravenous Acetaminophen on Pain Control and Post-operative Nausea and Vomiting: A Randomized Double-blind Clinical Trial
IntroductionAlthough laparoscopic surgery causes less postoperative pain than open surgery, however, the pain at the site of the laparoscopic port incision and in the shoulder and upper abdomen are the main complaints. Moreover, since postoperative nausea and vomiting (PONV) is the other complaints of these patients, it is important to adopt measures to address this issue (1-5).Today, acetaminophen is one of the most widely used analgesics due to its efficacy, safety, low side effects, and rare drug interactions (5, 6). Acetaminophen has different mechanism of actions that some of them have not been identified yet. It controls pain by preventing the production of prostaglandin E2, indirectly activating the cannabinoid receptor type 1, inhibiting the nitric oxide system by involving N-methyl-D-aspartate and substance P, and directly by stimulating descending serotonergic pathways that hinder pain signals transmitted by the spinal cord. Serotonin 5-Hydroxytryptamine (5-HT3) receptor antagonists, such as ondansetron, are at the front line of PONV treatment (7, 8). Furthermore, use of intravenous acetaminophen can also reduce PONV and the rate of antiemetic consumption (9-12). PONV is a common complication with a prevalence rate of 20-30% (3, 10). Ondansetron is the selective 5-HT3 antagonist which is effective in the prevention of PONV particularly if administered prior to the onset (3). In laparoscopic cholecystectomy, ondansetron administration can reduce the incidence of PONV in the first 4 h after the surgery (1). Ondansetron, in addition to triggering zone chemoreceptor in the medulla oblongata, affects the 5-HT3 receptor in the spinal cord on the pathway that modulates pain transmission signals. Some studies proposed that since ondansetron has antagonistic effects on 5ht3 receptors, it can reduce analgesic effects of acetaminophen. Therefore, ondansetron may be present at the 5-HT3 receptor of acetaminophen antagonist since the two medications have opposite effects on the 5-HT3 pathway (7).However, other studies have not concluded that co-administration of 5ht3 antagonists such as ondansetron and tropisetron could reduce the analgesic effects of acetaminophen. Moreover, review of literature showed one study which claimed direct analgesic effects for 5-HT3 antagonists (7, 12-17).Metoclopramide is another medication used to control PONV, and some studies reported the analgesic effects of this medication (18-22). Khazaei et al. and Karacabey et al. examined the effect of metoclopramide on migraine headaches and confirmed the results of previous studies regarding the positive effect of metoclopramide in reducing such headaches (19, 20). Ceyhan and colleagues conducted an experimental study on male rats and reported that metoclopramide could reduce incisional pain (22).Contrary to the laboratory results, the findings of some clinical studies have indicated that ondansetron did not reduce or even increased the analgesic effect of acetaminophen; however, the results of some studies have reported the blockage or reduction of this effect. According to our researches, there was no study on analgesic effect of co-administration of metoclopramide and acetaminophen and comparing its analgesic effect with ondansetron; therefore, this study was performed aimed to evaluate the effect of adding ondansetron and metoclopramide to intravenous acetaminophen on pain control and postoperative nausea and vomiting of patients undergoing laparoscopic cholecystectomy. MethodsThis double-blind clinical trial study with a parallel design was conducted in 2019 on patients undergoing laparoscopic cholecystectomy in the central operating room of Ghaem Hospital in Mashhad, Iran. According to the study by Koyunco et al. (7), the sample size was estimated to be 25 patients in each group by confidence level of 95% and power of 80%; finally, considering the possibility of 10% drop, 28 patients were considered in each group The study population consisted of all patients undergoing laparoscopic cholecystectomy. Participants were selected by Convenience Sampling method and entered the study after obtaining the written informed consent. The subjects were randomly allocated to three groups using the selection of sealed envelopes by the researcher. The first group (group A) received 1 g of intravenous acetaminophen by infusion 30 minutes before the end of surgery plus 4mg of ondansetron at the end of procedure. The second group (group B) was administered 1 g of intravenous acetaminophen by infusion 30 minutes before the end of surgery plus 8 mg of ondansetron at the end of procedure. The third group (group C) took 1 g of intravenous acetaminophen by infusion 30 minutes before the end of surgery plus 10 mg of metoclopramide at the end of procedure. Postoperative pain was measured as a primary outcome using the Numeric Rating Scale (NRS) after transferring the patient to the recovery room when patients' consciousness returned, before leaving the recovery room and 6 h after the operation in the ward. According to this scale, patients were asked to score their pain from a score of 0= no pain to 10= the most pain they have ever experienced. The validity and reliability of this scale have been investigated in various studies (23,24). Analgesic drug (other than acetaminophen) was injected for patients who had NRS score of ˃ 4.Demographic data, including age, weight, gender, and the duration of surgery were also recorded. The severity of nausea and vomiting before leaving the recovery was assessed by the PONV scale, which was developed by Wengritzky et al., who also evaluated its validity and reliability. In this 4-item scale, the highest score of items one or two is multiplied by the scores of items three and four to render the PONV score in the first 6 h after surgery (25).The inclusion criteria were: class I and II ASA age of 18-64 years, ability to communicate, no drug addiction, no analgesic administration in the last 24 h, no ondansetron or metoclopramide intake in the last 24 h, no chronic pain, and no history of sensitivity to acetaminophen, ondansetron, and metoclopramide.The exclusion criteria were: unusual and severe side effects of anesthesia, such as a severe drop (more than 50% of the baseline) in systolic blood pressure and heart rate that doesn’t respond to initial treatment, surgical complications which turned the procedure into an open surgery or despite managing the surgery with the closed approach, the operation lasted for more than 50% of the average of other operations, and the incidence of PONV, which required treatment with any of the medications in the family of 5-hydroxytryptamine inhibitors.All participants were completely monitored. General anesthesia was induced with propofol 2.5 mg/kg, atracurium 0.5 mg/kg, fentanyl 2 mcg/kg, and midazolam 20 mcg/kg. Maintenance of anesthesia was continued with propofol at a dose of 100-200 mcg/kg/min and remifentanil at a dose of 0.2-0.3 mcg/kg/min. The laparoscopic procedure and employed equipment were identical for all patients.In addition to the patients and the statistical analyzer, the person completing the NRS and PONV scales was also blinded to the groups. Kolmogorov-Smirnov test was applied to assess the normal distribution of quantitative variables. Qualitative variables were expressed in the form of frequency and percentage, quantitative variables in the form of mean (standard deviation), or with median (1st and 3rd quarters) in the case of a non-normal distribution. Chi-square and Fisher's exact test were used to evaluate the equality of proportions of qualitative variables among the three groups. Analysis of variance was used to compare the mean of quantitative normal variables in the three groups. The marginal model of generalized estimate equations (GEE) was used for intragroup and intergroup comparisons. Bonferroni's post hoc test was used for pairwise comparisons. Data was analyzed using SPSS software (version 25.0). P0.802), weight (P=0.724), and the duration of surgery (P>0.99). The summary of demographic information and the duration of surgery were presented in Table 1.The patients' PONV mean scores in the acetaminophen + ondansetron 4mg (group A), acetaminophen + ondansetron 8mg (group B), and acetaminophen + metoclopramide (group C) groups were AllocationEnrollment Assessed for eligibility (n=84)Excluded (n=0)¨ Not meeting inclusion criteria (n=0)¨ Declined to participate (n=0)¨ Other reasons (n=0)Randomized (n=84)Analysed (n=27) ¨ Excluded from analysis (n=0)Analysed (n=28) ¨ Excluded from analysis (n=0)Analysed (n=28) ¨ Excluded from analysis (n=0)AnalysisAnalysisAnalysisLost to follow-up (n= 0)Discontinued intervention (n=0) Lost to follow-up (n= 0)Discontinued intervention (n=0)Lost to follow-up (n=0)Discontinued intervention (due to surgical complications leading to open surgery) (n=1) Follow-UpFollow-UpFollow-Up¨ Group C: Received Acetaminophen + Metoclopramide (n=28)¨ Did not receive allocated intervention (n=0)¨ Group B: Received Acetaminophen + Ondansetron 8mg (n=28)¨ Did not receive allocated intervention (n=0)¨ Group A: Received Acetaminophen + Ondansetron 4mg (n=28)¨ Did not receive allocated intervention (n=0) Figure 1. CONSORT flow diagram of the study calculated at 160.61±241.31, 127.39±206.19, and 137.15±214.23, respectively. Kruskal-Wallis test showed no significant difference among the three groups in terms of PONV mean scores (P=0.812). A summary of the main findings was provided in Table 2.The mean of the interval between the end of surgery and the first analgesia injection were obtained at 2.14±1.18, 1.79±0.74, and 3.76±1.22 h in the A, B and C groups, respectively. Kruskal-Wallis test showed significant difference among the three groups in this regard (P0.999); however, significant differences were observed between the A and B groups (P0.999***a was expressed in frequency (percentage), b mean±standard deviation, c mean±standard deviation with median (1st quarters, 3rd quarters) in the case of a non-normal distribution.* Chi-square ** ANOVA *** Kruskal-Wallis The mean of pain score at the time of the first analgesia injection were estimated at 6.54±1.07, 6.79±0.83, and 7.04±8.60 in the A, B and C groups, respectively. Kruskal-Wallis test showed no significant difference among the three groups in this regard (P0.999B vs C P0.999After surgery and before leaving recovery (2)4.64±2.084 (3 , 6.75)Six hours after surgery (3)4.43±1.836 (3 , 6) acetaminophen + ondansetron 8mg (B)After surgery in recovery (1)4.57±2.063 (3 , 7)1 vs 2p>0.9991 vs 3p= 0.4412 vs 3p>0.999After surgery and before leaving recovery (2)4.89±2.024 (3 , 7)Six hours after surgery (3)5.11±1.576 (3 , 6) acetaminophen + metoclopramide (C)After surgery in recovery (1)1.59±1.672 (0 , 2)1 vs 2p= 0.2751 vs 3p<0.0012 vs 3p<0.001After surgery and before leaving recovery (2)2.00±1.002 (2 , 3)Six hours after surgery (3)3.11±1.783 (2 , 5) Tests of Model EffectsTime (Wald Chi-Square: 17.858; P-value<0.001)Group (Wald Chi-Square: 77.874; P-value<0.001) Pairwise ComparisonsControl vs Intervention 1<0.001Control vs Intervention 2<0.001Intervention 1vs Intervention 2: 0.198 DiscussionAccording to the results of the present study, the patients in the A and B groups who received ondansetron at doses of 4 and 8 mg with acetaminophen, respectively, experienced more pain than the group C who were administered 10 mg of metoclopramide with acetaminophen. Although the group B received a higher dose of ondansetron but had higher mean pain scores than the group A. The results of the study conducted by Ramirez et al. on the interaction and analgesic effect of I.V acetaminophen with 5-HT3 antagonists showed that the pain score in the acetaminophen and ondansetron group was not significantly different from the acetaminophen plus droperidol group, which is a dopamine antagonist similar to metoclopramide. Nevertheless, the administration of morphine in the ondansetron group was 3 times higher, which could indicate the contradictory effect of the 5-HT3 antagonist with acetaminophen (14). In the present study, the time of the first analgesia injection in acetaminophen + ondansetron 8mg (B) group was sooner than acetaminophen + ondansetron 4mg (A) group that could show the contradictory effect of the 5-HT3 antagonist with acetaminophen.Some discrepancy between the results of the mentioned study and the present study can be explained by the different time intervals for assessing the pain scores. Ramirez et al. also investigated this interaction in tonsillectomy among children and suggested the necessity of further studies in other surgeries (14). The findings of other studies indicate a reduction in the analgesic effect of acetaminophen when used concomitantly with 5-HT3 antagonists (7, 15). In the study performed by Koyuncu et al. on patients with abdominal hysterectomy, the postoperative pain scores were higher I those receiving acetaminophen plus ondansetron than those who received acetaminophen alone (7).In some studies, the concomitant use of acetaminophen and 5-HT3 antagonist not only did not reduce the analgesic effect of acetaminophen but also increased its analgesic effect (12, 13). Bhosale et al. reported that the co-administration of ondansetron and paracetamol did not decrease the analgesic effect of paracetamol (13). Based on the results of the above mentioned study, after taking acetaminophen, the concentration of serotonin will be increased, which is one of the mechanisms that acetaminophen inserted its analgesic property, however, 5-HT3 antagonists, such as ondansetron, can block it; nonetheless, their investigation has concluded differently when examined in clinical studies.This differences in the results can be attributed to two reasons; firstly, the mentioned study was performed on patients with local anesthesia and secondly, a small sample size (n=20) may be the effect of other analgesic mechanisms of acetaminophen other than increased serotonin. Furthermore, the findings of the studies by Bhosale et al. and Tiippana et al. have reported the independent analgesic effects of 5-HT3 antagonist (13,17).Another similar study was performed by Akhondi et al. on patients who underwent upper extremity fracture surgery, and the results revealed that the concomitant use of Apotel (I.V Acetaminophen) and ondansetron could reduce pain more than the administration of Apotel alone. One of the reasons for this difference in the results of their research with those of other studies could be related to the different types of surgery and methods of medication injection. In the present study, the medications were given to the patients in the forms of bolus and infusions for 30 min, but in the mentioned study, 4 ml/h of Apotel and ondansetron (4 mg ondansetron + 2 g Apotel + 100 ml normal saline) was infused during 25 h using a patient-controlled analgesia pump (12).The results of the mentioned study also indicated that the difference between the doses of pethidine administered as an analgesic after the surgery was not significant in the control and intervention groups, which was inconsistent with the assumption that Apotel with ondansetron leads to more analgesia than Apotel alone. In the present study, although the dose of ondansetron was increased from 4 mg to 8 mg and the mean pain scores were lower in patients receiving a lower dose of ondansetron, the results of the Kruskal-Wallis test showed no statistically significant differences. Nevertheless, in the acetaminophen + metoclopramide (C) group, metoclopramide not only controlled PONV (none of the three groups showed a statistically significant difference in PONV score regardless of the intervention), but also reduced pain more than the other medication administered in the other two groups.Regarding the higher analgesic effect of acetaminophen in the presence of metoclopramide in the acetaminophen + metoclopramide (C) group, it can be stated that in addition to the fact that this increase might be due to the lack of blocking effect of acetaminophen on increasing serotonin compared to ondansetron, a reduction in pain could also be due to the analgesic effects of metoclopramide. Various studies have been performed to investigate the anal
Autophagy induction regulates influenza virus replication in a time-dependent manner
Autophagy plays a key role in host defence responses against microbial infections by promoting degradation of pathogens and participating in acquired immunity. The interaction between autophagy and viruses is complex, and this pathway is hijacked by several viruses. Influenza virus (IV) interferes with autophagy through its replication and increases the accumulation of autophagosomes by blocking lysosome fusion. Thus, autophagy could be an effective area for antiviral research.Methodology. In this study, we evaluated the effect of autophagy on IV replication. Two cell lines were transfected with Beclin-1 expression plasmid before (prophylactic approach) and after (therapeutic approach) IV inoculation.Results/Key findings. Beclin-1 overexpression in the cells infected by virus induced autophagy to 26 %. The log10haemagglutinin titre and TCID50 (tissue culture infective dose giving 50 % infection) of replicating virus were measured at 24 and 48 h post-infection. In the prophylactic approach, the virus titre was enhanced significantly at 24 h post-infection (P≤0.01), but it was not significantly different from the control at 48 h post-infection. In contrast, the therapeutic approach of autophagy induction inhibited the virus replication at 24 and 48 h post-infection. Additionally, we showed that inhibition of autophagy using 3-methyladenine reduced viral replication.
Conclusion. This study revealed that the virus (H1N1) titre was controlled in a time-dependent manner following autophagy induction in host cells. Manipulation of autophagy during the IV life cycle can be targeted both for antiviral aims and for increasing viral yield for virus production
Corneal topography and higher-order aberrations in patients with type 2 diabetes mellitus
Background: Changes in blood sugar levels cause alterations in the anterior segment and retina of the eye. This study was aimed at evaluating corneal topography, aberrometry, and corneal asphericity in patients with treatment-naive type 2 diabetes mellitus (T2DM).
Methods: Participants with treatment-naive T2DM were enrolled in this cross-sectional study. The inclusion criteria were glycated hemoglobin A1c (Hb A1c) greater than or equal to 7.5% and absence of other ocular or systemic diseases. Patients who refused to participate or had a history of topical or systemic steroid use, hyperlipidemia, hypertension, anemia, prior ocular disorder or surgery, diabetic retinopathy, glaucoma, cataract, active ocular inflammatory or infectious disease, or contact lens use were excluded. All participants underwent a comprehensive ophthalmic examination. The Pentacam HR Scheimpflug tomography system (Pentacam High Resolution; Oculus, Wetzlar, Germany) was used to measure the anterior-segment parameters.
Results: Sixty eyes of 30 patients with a male-to-female ratio of 1:1 were included; the mean (standard deviation [SD]) age and Hb A1c were 51.63 (6.73) years and 8.82% (1.31%), respectively. The mean (SD) values of central corneal thickness, root mean square (RMS) of total aberration, RMS of lower-order aberrations, RMS of higher-order aberrations, spherical aberration, 0° coma, 90° coma, flat anterior keratometry (K), steep anterior K, mean anterior K, anterior topographic astigmatism, flat posterior K, steep posterior K, mean posterior K, posterior topographic astigmatism, anterior corneal asphericity, and posterior corneal asphericity were 540.22 (24.47) µm, 1.72 (0.73) µm, 1.63 (0.73) µm, 0.51 (0.17) µm, + 0.31 (0.09) µm, - 0.06 (0.15) diopters (D), 0.003 (0.21) D, 43.87 (1.49) D, 44.69 (1.50) D, 44.28 (1.44) D, + 0.82 (0.83) D, - 6.25 (0.27) D, - 6.55 (0.31) D, - 6.40 (0.28) D, - 0.30 (0.15) D, - 0.32 (0.12) Q-value, and - 0.47 (0.17) Q-value, respectively.
Conclusions: We presented the mean values of Pentacam parameters for aberrometry, keratometry, and corneal asphericity in patients with treatment-naive T2DM. These values could serve as a baseline for prospective monitoring of the ocular health status of this cohort and for comparison with future cohorts of patients with well-controlled T2DM. Further studies are required to assess the presence and applicability of ocular changes following intensive blood glucose control in T2DM and further understand the related pathophysiology
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