Safety Index Research Articles

Assessment of train running safety on railway bridges based on velocity-related indices under random near-fault ground motions

Random analysis has emerged as the dominant approach for analyzing train-bridge coupled (TBC) systems, replacing deterministic analysis. This shift is driven by considerations of system economy and randomness. However, the seismic train running safety assessment with multiple non-Gaussian distribution parameters faces the double dilemma of low computational efficiency and inaccuracy for TBC systems. In this study, an approach is applied by the combination of the new point estimate method and moment expansion approximation (NPEM-MEA) to address this problem. Furthermore, the application of this approach is illustrated by the random dynamic responses of a three-dimensional TBC system subjected to random near-fault ground motions. Validation of the NPEM-MEA’s feasibility is conducted using the Monte Carlo method, and comparative analysis confirms the accuracy and efficiency of the method. Additionally, the influences of random near-fault ground motions are discussed based on the random dynamic responses and train running safety indices in the TBC system. The simulation results underscore the necessity of simultaneously considering the randomness of multiple parameters in seismic train running safety assessment. This methodology holds potential for safety assessments involving non-Gaussian random processes in complex systems of a similar nature.

Proposal of a Protocol for the Safe Removal of Post-Earthquake Provisional Shorings

The recent seismic events in Italy, including the earthquakes in L’Aquila in 2009 and central Italy in 2016, have significantly impacted the historical centers of small and medium-sized cities. These events directly affected their ancient masonry building heritage, resulting in severe damage. In order to minimize the risk of collapses and prevent further harm to people and structures until restoration efforts can be carried out, provisional post-seismic shorings have been extensively employed. These occurrences motivated several studies focused on the selection and assembly of post-seismic shorings, considering the various rigid failure mechanisms that may occur in a wall or section of an ancient masonry building. Yet, thus far, the critical considerations concerning the disassembly of these shorings, which significantly influence the repair process of a compromised structure from safety, organizational, and economic perspectives, have been overlooked. This research endeavors to establish a protocol for the dismantling of provisional shorings. To this end, a preliminary risk assessment tool has been devised, furnishing a safety index that correlates with the level of risk associated with shoring removal, along with corresponding risk categories. The study recommends preliminary interventions, categorized as mandatory or optional, to mitigate the risk prior to shoring removal. Furthermore, specific guidelines are provided based on the assessed risk level indicated by the safety index. To illustrate the application of this risk assessment tool, a case study involving an ancient masonry building in L’Aquila is presented.

A COMPARATIVE STUDY ON SAFETY, EXERGETIC, AND ENVIRONMENTAL ANALYSIS FOR BIOMETHANOL VIA BIOGAS REFORMING

The energy crisis and global warming caused by fossil fuel combustion have received increasing attention in recent years. Biomethanol is a clean and environmentally friendly energy produced by reforming biogas-derived syngas. To investigate the most suitable and efficient biomethanol production process, this paper compares the biomethanol production via three different biogas reforming processes, namely steam reforming, autothermal reforming, and tri-reforming using Aspen Plus simulator through safety index, energy and exergetic, and environmental analyses. For the process performance, the tri-reforming process achieved the highest energetic and exergetic efficiencies of 63.17% and 41.24%, respectively, due to producing the highest yield of methanol. In the environmental analysis, the steam reforming of the biogas process showed the lowest CO2 emission intensity of 3.16 ton CO2/ton methanol. The major source of CO2 emission is the combustion of biogas. The Dow Fire and Explosion Index was used for the safety aspect. The biomethanol reactor was discovered to be the most hazardous equipment.

Is the safety index of modern safety integrity level(SIL) truly appropriate for the railway?

Safety is paramount in rail transportation. The International Safety Standard IEC 61508, issued by the International Electrotechnical Commission (IEC) in 2000, describes the modern concept of safety and the specifications for safety evaluation in a systematic manner. On this basis, the EN 50129 railway transportation safety standard and safety integrity level(SIL) are established. Through the above analysis, the relationship between safety-related system reliability, acceptable risk, and safety index is summarized. It is clear that the safety index is based on acceptable risks. Nonetheless, as the economy and society advance, the safety index mandated by the SIL falls behind. Consequently, the principles and methodologies for calculating the safety index are presented. The paper proposes a reference for the Chinese railway safety index based on actual data from the Chinese railways over the past few years.

Safety Index, Evaluation Model, and Comprehensive Evaluation Method of Power Information System under Classified Protection 2.0

Aiming at the problems of the low integration of the current power information system security assessment method with classified protection 2.0, strong subjectivity, and the vague quantification of objective indexes, this article proposes to establish a safety index system suitable for the electric power information system with the existing safety inspection standards for power systems on the basis of the classified protection 2.0 evaluation system. Additionally, it quantifies each index through a quantitative method combining subjective and objective methods and uses the analytic hierarchy process entropy method to obtain the combined weight of the evaluation index system. Finally, this paper summarizes the expert scores and the graded protection evaluation reports of the six systems into the original data for comprehensive weight calculation and analyzes the rationality of the weight change. The comparison and analysis of the closeness of the TOPSIS (Technique for Order Preference by Similarity to an Ideal Solution) and the evaluation score of the equal guarantee have confirmed the scientificity and rationality of the evaluation model. It provides a reasonable logical idea for the implementation of the classified protection 2.0 system in the power information system.

Brain Protection Effects of Mild Hypothermia Combined with Distant Ischemic Postconditioning and Thrombolysis in Patients with Acute Ischemic Stroke.

To assess the effectiveness and molecular mechanisms of mild hypothermia and remote ischemic postconditioning (RIPC) in patients with acute ischemic stroke (AIS) who have undergone thrombolysis therapy. A total of 58 AIS patients who received recombinant tissue plasmin activator (rt-PA) intravenous thrombolysis were included in this prospective study. Participants were randomly allocated to the experimental group (rt-PA intravenous thrombolysis plus mild hypothermic ice cap plus remote ischemic brain protection, n = 30) and the control group (rt-PA intravenous thrombolysis plus 0.9% saline, n = 28). The RIPC was performed for 14 consecutive days on both upper limb arteries spaced 2 minutes apart. Five cycles of ischemia-reperfusion were performed sequentially (2-2, 3-3, 4-4, 5-5, 5-0 minutes, respectively). The outcome measures of the National Institute of Health stroke scale (NIHSS) score, volume of cerebral infarction, serum levels of superoxide dismutase (SOD), malondialdehyde (MDA), interleukin-1β, tumor necrosis factor α, nuclear factors kappa B (NF-κB), and NOD-1ike receptor pyrin 3 (NLRP3) were evaluated at different time points after treatment. Similarly, the 90-day modified Rankin Scale (mRS) scores were compared between the two groups. After treatment, the NIHSS score, MDA, NF-κB, and NLRP3 levels in the experimental group were significantly lower than those in the control group (p < 0.05). While the SOD in the experimental group was significantly higher than in the control group (p < 0.05), the NIHSS scores decreased within groups (all p < 0.05) in both experimental and control groups. The 90-day mRS score (0-2 points) in the experimental group was significantly higher than that in the control group (73.33% vs. 53.57%, p < 0.05) and no significant differences were observed in the safety indices between the two groups (all p > 0.05). Our study shows that combining mild hypothermia and RIPC has a positive effect on brain protection and can significantly reduce the oxidative stress and associated outburst of inflammatory response. The Clinical Trial Registration number is ChiCTR2300073136.

Design, synthesis, and biological evaluation of indole-2-carboxamides as SARS CoV-2 main protease inhibitors

Using a repurposing approach, a series of previously reported antiproliferative indole-based carboxamides (9–23) were reassessed for their anti-SARS-CoV-2 viral activity as main protease (SARS-CoV-2 Mpro) inhibitors. The structure of the indole-based carboxamides was validated by comparing the acquired data to previously report physicochemical and NMR spectroscopy data. The anti-SARS-CoV-2 activity of the synthesised compounds was tested in Vero-E6 cells using SARS-CoV-2 (NRC-03-nhCoV) virus. MTT cytotoxicity assay results demonstrated that compounds 9–23 had CC50 (50% cytotoxicity concentration) values ranging from 325.60 to 578.50 μM and safety indices ranging from 21.40 to 99.60. Most of the compounds examined significantly inhibited NRC-03-nhCoV virus replication, with IC50 values ranging from 3.60 μM to 15.20 μM, with compounds 11, 19, and 20 having the most potent anti-SARS-COV-2 activity. The inhibitory effect of compounds 11, 13, 14, 19 and 20 against SARS-CoV-2 Mpro was investigated. The findings of this test were consistent with the anti-SARS CoV-2 experiment. Inflammatory cytokine tests revealed that compounds 11, 19 and 20 have antiviral effectiveness against SARS-CoV-2 and can reduce hyper inflammation. Finally, docking studies of the novel compounds in the SARS CoV-2-Mpro active site revealed a good match.

Intrastromal Corneal Ring Segments: Effect of Depth of Implantation in Visual, Refractive and Topographic Outcomes in Keratoconus Patients.

To evaluate visual, refractive and topographic outcomes of intracorneal ring segment implantation in relation to the achieved segment depth, using the manual technique. Ophthalmology Department, Hospital de Braga, Braga, Portugal. Retrospective cohort study. We obtained 104 eyes of 93 keratoconus patients submitted to Ferrara intracorneal ring segment (ICRS) implantation, using a manual technique. Subjects were divided into 3 groups according to the achieved depth of implantation: 40-70% (Group 1), 70-80% (Group 2), and 80-100% (Group 3). Visual, refractive and topographic variables were evaluated at baseline and 6-months. Topographic measurement was performed using Pentacam. Thibos-Horner and Alpins methods were used to analyze the vectorial change of refractive and topographic astigmatism, respectively. We found a significant improvement of UDVA and CDVA in all groups at 6-months (P<0.005); no differences were observed regarding safety and efficacy indexes in the three groups (p>0.05). Manifest cylinder and spherical equivalent significantly reduced in all groups (P<0.05). Topographic evaluation showed a significant improvement of all parameters in the three groups (P<0.05). A shallower (group 1) or deeper (group 3) implantation was associated with topographic cylinder overcorrection, a higher magnitude of error and a higher mean centroid postoperative corneal astigmatism. ICRS implantation with manual technique showed to be equally effective in terms of visual and refractive outcomes despite the depth of implantation; however, shallower or deeper implants were associated with topographic overcorrection and a higher mean centroid postoperative astigmatism, which explain the lower topographic predictability associated with manual surgery for ICRS implantation.

Evaluation of long-term clinical outcomes after Toric Implantable Collamer Lens implantation.

To evaluate the long-term (8-10 years) outcomes of Toric Implantable Collamer Lens (TICL) surgery. Nagoya Eye Clinic, Nagoya, Aichi, Japan. Retrospective observational study. We enrolled patients who underwent TICL surgery from 2005-2009 to correct myopia and myopic astigmatism. The safety, efficacy, predictability, astigmatism correction efficacy, and complications were evaluated using preoperative, 1-year postoperative, and final examination data. We included 133 eyes of 77 patients. At the final visit, the mean uncorrected and corrected visual acuity were -0.01±0.2 and -0.17±0.05, respectively. The mean safety and efficacy indices were 0.91±0.26 and 0.68±0.21, respectively. The manifest astigmatism was -0.45±0.43 D. The mean corneal astigmatism change from 1 year post-surgery to the final visit was 0.40±0.26 D. Of the 38 eyes with a change in corneal astigmatism ≥0.5 D, 30 eyes (78.9%) changed to against-the-rule (ATR) astigmatism, one (2.6%) changed to oblique astigmatism, and seven changed (18.4%) to with-the-rule (WTR) astigmatism. The mean manifest astigmatism change from 1 year post-surgery to the final visit was 0.43±0.52 D. Of the 60 eyes with a change in manifest astigmatism ≥0.5 D, 25 (41.7%) changed to ATR astigmatism, 18 (30.0%) changed to oblique astigmatism, and 17 (28.3%) changed to WTR astigmatism. During follow-up, eight of 133 eyes (6.0%) developed anterior subcapsular cataracts, among which four (3.0%) underwent TICL removal and phacoemulsification and aspiration. No vision-threatening complications occurred. TICL surgery showed good long-term astigmatism-correcting effects, although the long-term uncorrected visual acuity decreased. The procedure was effective in correcting myopia and astigmatism.

Incidence and Management of Epithelial-Related Complications After SMILE.

To investigate the incidence and management of only epithelial-related complications following small incision lenticule extraction (SMILE). A retrospective, single-site study analyzed patients who underwent SMILE at Hoopes Vision Clinic in Draper, Utah, from June 2017 to February 2023. Demographic data and preoperative parameters were reviewed. Postoperatively, patients were assessed for visual acuity and complications at different time points. Statistical analyses were conducted between the control and complication groups. Four hundred and thirty-two eyes of 220 patients received SMILE. Postoperative epithelial-related complications were indicated in 68 (15.7%) eyes, including anterior basement membrane (ABM) changes (five [1.2%]) eyes), epithelial ingrowth (nine [2.1%] eyes), erosion (two [0.5%] eyes), rough epithelium (18 [4.2%] eyes), epithelial defect (12 [2.8%] eyes), diffuse lamellar keratitis (DLK) secondary to epitheliopathy (two [0.5%] eyes), microstriae secondary to epitheliopathy (four [0.9%] eyes), interface debris (21 [4.9%] eyes), and incisional fibrosis (one [0.2%] eye). There was a statistically significant difference in age, with older patients more likely to develop epitheliopathy postoperatively (P = 0.001). Additionally, patients with epithelial-related complications were more likely to receive photorefractive keratectomy (PRK) enhancement after SMILE than the control (P = 0.001). However, there was no statistical difference in uncorrected distance visual acuity (UDVA) better than 20/20 and corrected distance visual acuity (CDVA) between the complications group and the control at the last postoperative visit (P = 0.974 and 0.310, respectively). There was no statistically significant difference in the safety and efficacy indices between the complications and control group (P = 0.281 and 0.617, respectively). In our study, epithelial-related complications were more prevalent in older patients and predisposed patients to require PRK enhancements after recovery from SMILE. Despite the incidence of epithelial-related complications, visual prognoses were favorable and achieved through various management strategies.

Hospital Disaster Preparedness: A Comprehensive Evaluation Using the Hospital Safety Index

Mass-casualty incidents and disaster scenarios pose significant challenges for medical facilities, necessitating robust preparedness measures. This study aimed to evaluate the preparedness of a specific medical facility in Poland, using the hospital safety index (HSI). A comprehensive analysis of structural, functional, and organizational factors was conducted, assessing facility infrastructure, technical facilities, safety standards, work organization, cooperation with external facilities, human resource management, crisis planning, and communication strategies. The facility exhibited strengths in infrastructural requirements and inter-facility cooperation. Areas of improvement included adherence to safety procedures, crisis communication, and the frequency of evacuation drills. Furthermore, recommendations were provided for enhancing nurse reserves, adopting lean management, promoting a safety culture, and refining business continuity plans. The findings should be interpreted with caution, due to the single-facility focus, potential HSI protocol subjectivity, and the possible Hawthorne effect. This study underscores the importance of continuous research and improvement in crisis management strategies and disaster-victim care, emphasizing the pivotal role of the HSI as an evaluative tool.

Evaluation of the Risk of Truck Platoon under Crosswind regarding the Lateral Displacement on Horizontal Curves

Driving safety on horizontal curves under crosswinds has always been a concern for researchers. However, previous studies focused on single vehicles, especially single trucks. The safety of the truck platoon under crosswinds on horizontal curves was rarely examined. To fill such a gap, this study establishes a model for evaluating the safety of truck platoons under crosswinds on curves. After obtaining aerodynamic coefficients, a cosimulation model of a three-truck platoon is established with Trucksim and Simulink. The influencing factors on the lateral displacement of the truck platoon were analyzed, and the safety of the truck platoon under crosswinds on horizontal curves was then quantified with the response surface method. The results show that the fully autonomous platoon is safer than the human-led platoon. In a three-vehicle platoon, the smaller the lateral displacement of the truck, the further back the truck, and the lateral displacement of the vehicle increases with the loading of the truck. The safety index is computed to quantify the reliability of the truck platoon. The results indicate that the safety index increases with a decrease in the mean wind velocity and mean vehicle velocity and increases with an increase in the mean radius. When crosswinds come from the inside of the curve, the safety index increases with an increase in the mean superelevation; for crosswinds from the outside of the curve, the safety index rises with the drop of superelevation. The proposed approach can quantify the safety level of truck platoons under crosswinds on horizontal curves, and the results provide guidance to support the decision-making of transportation management agencies.

Assessing hospital disaster preparedness: A scoping review of available tools.

One of the problems faced after a disaster is health service for victims and hospitals play a critical role in handling disaster victims. Therefore, hospitals must enhance their preparedness and establish a disaster-safe environment to effectively fulfill their role as a provider of health services during a crisis. The aim of this scoping review was to identify hospital disaster preparedness tools used around the globe and to identify the critical aspects that need to be included in hospital disaster preparedness. This study used the five stages of Arksey and O'Malley's scoping review framework to determine what disaster preparedness tools can be used in a hospital setting. The electronic literature searches of English articles published between 2018 and 2023 were conducted using PubMed, Elsevier, ProQuest, ISI Web Science, and Google Scholar databases. The searched keywords were combined into several search terms such as sub-discipline, subtitle, year, language, and content type. The keywords of sub-title searching were "preparedness", "hospital" and "disaster". After applying some inclusion criteria, ten articles out of 1,221 identified records were included in the final analysis. The World Health Organization (WHO) Hospital Safety Index, WHO Hospital Emergency Checklist or their modified versions, and modified Public Health Emergency Preparedness were tools used in assessing hospital disaster preparedness. These tools evaluate some aspects such as structural safety, non-structural safety, and functional capacity. The studies indicated that each tool used to measure hospital disaster preparedness has strengths and weaknesses in each assessed aspect. Although some tools have been recommended to assess hospital disaster preparedness, assessing each tool validity and reliability are critical and needs to be conducted.

Predictive worker safety assessment through on-site correspondence using multi-layer fuzzy logic in outdoor construction environments

Construction sites remain highly perilous work environments globally, exposing employees to numerous hazards that can result in severe injuries or fatalities. To resolve this several solutions based on quantitative approaches have been developed. However the wide adoption of preexisting solutions is hindered by lack of accuracy. To this aim the development of an efficient fuzzy inference system has become a de-facto necessity. In this paper, we propose an edge inference framework based on multi-layered fuzzy logic for safety of construction workers. The proposed system employs an edge computing-based framework where IoT devices collect, store, and manage data to offer safety services. Multi-layer fuzzy logic is applied to infer the worker safety index based on rules that consist of construction environment factors. The multi-layer fuzzy logic is fed with weather, building and worker data collected from IoT nodes as inputs. The safety risk assessment process involves analyzing various factors. Weather information, such as temperature, humidity, and rainfall data, is considered to assess the risk to safety. The condition of the building is evaluated by analyzing load, strain, and inclination data. Additionally, the safety risk to workers is analyzed by taking into account their heart rate and location information. The initial layer's outputs are utilized as inputs for the subsequent layer, where an integrated safety index is inferred. Ultimately, the safety index is generated as the final outcome. The system's results are conveyed through warnings and an error measurement on a safety scale ranging from 1 to 10. Furthermore, web service is developed to allow the construction management to check the worker safety condition of the construction site in real-time, while also monitoring the operational status of the IoT devices, allowing for the early detection of sensor malfunction and the subsequent guarantee of worker safety. Extensive evaluations conducted to test the performance of the developed framework verify its efficiency to provide improved risk assessment, real-time monitoring, and proactive safety actions, encouraging a safer and more productive work environment.

Chemical and Process Inherent Safety Analysis of Large-Scale Suspension Poly(Vinyl Chloride) Production

In this work, a safety assessment was carried out for the suspension polymerization method, known for the lack of studies about its sustainable performance and long history of chemical accidents. Therefore, a safety analysis was conducted using the inherent safety methodology to assess and determine the inherent risks of the poly(vinyl chloride) (PVC) suspension production process using computer-aided process engineering (CAPE). The indicators were calculated using data from safety databases and the specialized literature, considering downstream stages like vinyl chloride monomer (VCM) recovery, PVC purification and PVC drying. The obtained indicators revealed that the process has a negative performance regarding inherent safety, with a total inherent safety index of 30. The chemical inherent safety index had a value of 19, with the main chemical risk of the process being presented by the vinyl chloride monomer (with a value of 11), along with the risk of the exothermic reactions. The process safety index had a value of 15, highlighting the inventory as the primary concern of the process (with a value of 5), followed by the presence of unsafe equipment such as furnaces, burners, and dryers. The safety structure index had a score of 3, categorizing the process as probably risky, with the reaction and purification stages being more susceptible to accidents. Lastly, it is recommended to reduce the size of the process inventory and to substitute out unsafe process units.

Risk assessment of 369 pesticide residues in banana from Hainan province of China through UPLC-Q-TOF/MS

In this study, residues of 369 pesticides were determined in 123 banana samples by UPLC-Q-TOF/MS/MS to evaluate the potential risk of pesticide residues in bananas and investigate the quality and safety situation in Hainan province, China. The results indicated that 107 samples contained 1–10 residues. Insecticides and fungicides were the groups with the highest detection frequencies in bananas. The most frequently detected pesticides in bananas were pyraclostrobin (50.41%), prochloraz (38.21%), imidacloprid (33.33%), acetamiprid (25.20%) and carbendazim (19.51%); 13 samples were unqualified with the failure rate 10.57%. The index of food safety (IFS) of all detected pesticides in bananas was less than 1, and the value of the acute reference dose (ARfD) and acceptable daily intake (ADI) of pesticide residues detected in different populations were less than 100%, indicating an acceptable safety risk of the pesticide residues. As for risk coefficient (R), there was a high early warning risk for fluxapyroxad and imidacloprid, as well as a moderate early warning risk for propiconazole. According to the risk ranking, we found 3 kinds of medium-risk pesticides, including acetamiprid, difenoconazole and prochloraz. They should be considered in the key control risk factors and continuously monitored to protect people’s health. However, undue concern was unnecessary since the assessment was based on a conservative assumption.

An evaluation model of sustainable efficiency for container terminals

AbstractThe purpose of this paper is to evaluate the sustainable efficiency of container terminals (CTs). By the definition of United Nations Conference on Trade and Development (UNCTAD), business sustainable development includes three domains: Economics, Environment, and Society. Accordingly, based on the definition and the practical features of CT operations, this paper assesses sustainable efficiency for CTs from three perspectives: container throughput, CO2 emissions, and occupational safety. In this paper, a modality movement and a fuzzy grey relational analysis (GRA) approach are first proposed to estimate CO2 emissions and occupational safety index for CT operators, respectively. A hybrid slacks‐based measure (SBM)‐DEA model is then developed to assess the sustainable efficiency of CT operators. Finally, the CT operators in the Port of Kaohsiung are empirically investigated to validate the research model. Based on the results, theoretical and practical implications for the management of CT operators and port authorities are discussed.

Design, Synthesis and Biological Evaluation of Novel PEG-Rakicidin B1 Hybrid as Clostridium difficile (CD) Targeted Anti-Bacterial Agent.

Rakicidin B1 was isolated and purified from the culture broth of a marine Streptomyces sp. as a potent anti-cancer agent, and lately the compound and its derivatives have firstly been found to possess anti-Clostridium difficile (CD) activity but with high cytotoxicity. Herein, following our previous discovery on anti-CD activity of Rakicidin B1, structure modification was performed at the OH position of Rakicidin B1 and a new Rakicidin B1-PEG hybrids FIMP2 was facilely designed and synthesized by conjugating the PEG2000 with the scaffolds of Rakicidin B1 via the linkage of carbamate. The cytotoxicity of the FIMP2 was first evaluated against three different cancer cell lines, including HCT-8 cells, PANC-1, and Caco-2, with IC50 values at 0.519 μM, 0.815 μM, and 0.586 μM, respectively. Obviously, as compared with a positive control group treated with Rakicidin B1, the IC50 value of FIMP2 increased by nearly 91-fold, 50-fold, and 67-fold, suggesting that the PEGylation strategy significantly reduced the cytotoxicity of FIMP2. Thus, this preliminary result may be beneficial to increase its safety index (SI) value due to the decreased cytotoxicity of FIMP2. In addition, this decreased cytotoxicity of FIMP2 was further confirmed based on a zebrafish screening model in vivo. Thereafter, the anti-CD activity of FIMP2 was evaluated in vivo, and its efficacy to treat CDI was found to be better than that of vancomycin. The mortality and recurrence rate of FIMP2 is not as low compared with that of vancomycin; these results demonstrated that compound FIMP2 is a new, promising anti-CD agent with significant efficacy against CD recurrence with low cytotoxicity towards bodies.

Comparison of Conventional Versus Trans-Epithelial Photorefractive Keratectomy in Hyperopia Treatment: A Contralateral Study

Background: This study was planned to compare Trans - epithelial Photorefractive Keratectomy (TPRK) and Alcohol Assisted Photorefractive Keratectomy (AAPRK) laser vision correction in hyperopia and compound hyperopic astigmatism.&#x0D; Methods: This quasi-experimental study was conducted on patients with hyperopia and hyperopic-astigmatism, whose eye laterality was randomly assigned to undergo TPRK versus AAPRK using SCHWIND AMARIS 1050RS (SCHWIND eye-tech-solutions, Germany). Follow up time was 1, 3, 6 and 12 months after surgery.&#x0D; Results: 112 eyes of 56 patients with mean age of 32.6 years included, of which 51.8% were female and 48.2% were male. Both TPRK and AAPRK methods were able to correct hyperopia and astigmatism safely and efficiently (p&lt;0.05 in all cases). Postoperative vision characteristics were similar in both methods (p=0.23 for sphere, p=0.52 for cylinder, p=0.064 for axis, and p=0.35 for BCVA) postoperatively. Corneal haze was observed in 44% of the patients with a direct strong correlation with hyperopia severity (r=0.607). Post-operative pain was observed in 60% of the patients with a direct weak correlation with hyperopia severity (r=0.27). Mild photophobia was seen in 42% of the patients with a direct weak correlation between photophobia and hyperopia severity (r=0.36). Epithelial healing time lasted an average of 3.48 days and there was a direct and moderate correlation with hyperopia severity (r=0.4). Safety index in TPRK and AAPRK was 0.54 and 0.45, respectively, with no significant difference (p=0.42); Efficacy index was 0.96 and 0.9 in TPRK and AAPRK, respectively and there was no significant difference between two groups (p=0.23). No complication was observed in all of the patients.&#x0D; Conclusion: TPRK and AAPRK laser vision correction are both safe and efficient in hyperopia and compound hyperopic astigmatism. There is no significant difference regarding epithelial healing time, post-operative pain and haze formation between two procedures.

Determining safety aspects of Differential Speed Limit on Indian Expressway

Optimization of operating speed limit on any class of road is the biggest task faced by the transportation experts. A variety of speed control or management techniques are available all around the globe to minimize the frequency of over-speeding or for increasing the acceptability of the posted speed limit. In this study, a comparison is carried out between Uniform Speed Limit (USL) and Differential speed Limit (DSL) on an Expressway in India, using microsimulation package PTV VISSIM. In USL, a single speed limit is implemented for all class of vehicles whereas DSL strategy have two distinct speed limit for two different class of vehicles i.e., passenger carrying vehicles and goods carrying vehicles. Multiple Key Performance Indicators (KPIs) were considered. Results suggested that DSL seems to be the better strategy on the roads accommodating high speeds like Expressways under heterogenous conditions. Four out of five KPIs were showing the results in favor of DSL strategy in comparison to USL strategy. KPIs like speed variance, Road Safety Index (RSI), no. of vehicles having Deceleration-Rate-to-Avoid-Collision (DRAC) > 3.35 m/sec2 and no. of lane changes were showcasing better results in case of DSL strategy in comparison to USL strategy.