Stoplight Research Articles

Optimization of cycle time on signalized intersections of H.E.A Mokodompit Street – M.T Haryono – H.A. Nasution Kendari city based on traffic flow volume

Intersection of H.E.A. Mokodompit Street – M.T. Haryono – H.A. Nasution is one of the signalized intersections in Kendari City which has congestion problems, vehicle accumulation and vehicle queues at each arm of the intersection at rush hour due to the large volume of traffic flow and not optimal cycle timing from the traffic light signal. The purpose of this study is to optimize the cycle time of traffic control light signals based on traffic volume and to analyze the performance of these intersections. The results of the analysis based on the volume of traffic flow obtained the optimal cycle time of 72 seconds with the division of green time in each approach by 18 seconds for the north approach, 14 seconds for the eastern approach and 28 seconds for the south approach. The degree of saturation at each intersection arm is 0.82 which is at the service level D.

Filtering Light-Emitting Diodes to Investigate Amber and Red Spectral Effects on Lettuce Growth.

Red and blue light are the principal wavelengths responsible for driving photosynthetic activity, yet amber light (595 nm) has the highest quantum efficiency and amber-rich high pressure sodium lamps result in superior or comparable plant performance. On this basis, we investigated how lettuce plant growth and photosynthetic activity were influenced by broad and narrow light spectra in the 590–630 nm range, by creating amber and red light-emitting diode (LED) spectra that are not commercially available. Four different light spectra were outfitted from existing LEDs using shortpass and notch filters: a double peak spectrum (595 and 655 nm; referred to as 595 + 655-nm light) that excluded 630-nm light, 595-nm, 613-nm, and 633-nm light emitting at an irradiance level of 50 W·m−2 (243–267 µmol·m−2·s−1). Shifting LED wavelengths from 595 nm to 633 nm and from 595 nm to 613 nm resulted in a biomass yield decrease of ~50% and ~80%, respectively. When 630-nm light is blocked, lettuce displayed expanded plant structures and the absence of purple pigmentation. This report presents a new and feasible approach to plant photobiology studies, by removing certain wavelengths to assess and investigate wavelength effect on plant growth and photosynthesis. Findings indicate that amber light is superior to red light for promoting photosynthetic activity and plant productivity, and this could set precedence for future work aimed at maximizing plant productivity in controlled environment agriculture.

Evaluation of oral potentially malignant disorders with autoflorescence, reflectance spectroscopy and vital staining and their correlation with histopathology – Hospital based prospective study

ObjectivesTo evaluate diagnostic efficacy of Identafi® and toluidine blue in screening of Oral Potentially Malignant Disorders (OPMDs). Materials and methodsForty nine patients (63 lesions) with OPMDs visiting Department of Oral Medicine and Radiology, B.P.Koirala Institute of Health Science (BPKIHS) were included in the study. After thorough history and oral examination, screening was done by Identafi® followed by toluidine blue staining. Then incisional biopsy under local anesthesia was performed from the site showing positive change followed by histopathological examination. ResultsThe overall sensitivity and specificity of Identafi®’s violet light was 73% and 46.2%. The overall sensitivity and specificity of Identafi®’s green-amber light were 78.4% and 15.4% respectively. The overall sensitivity and specificity of toluidine blue were 51.4 and 84.6 respectively. A statistically-significant association was observed between the toluidine blue and histopathology results, (p = 0.04), p value set at ≤ 0.05. ConclusionIdentafi®’s violet light and green amber light are more sensitive in detecting true positives. Toluidine blue is highly specific in ruling out true negative cases. The screening of OPMDs will help in selecting proper biopsy site followed by early diagnosis and intervention, hence increasing the prognosis, outcome and decrease complications associated with it.

A photoswitchable GPCR-based opsin for presynaptic inhibition

Optical manipulations of genetically defined cell types have generated significant insights into the dynamics of neural circuits. While optogenetic activation has been relatively straightforward, rapid and reversible synaptic inhibition has proven more elusive. Here, we leveraged the natural ability of inhibitory presynaptic GPCRs to suppress synaptic transmission and characterize parapinopsin (PPO) as a GPCR-based opsin for terminal inhibition. PPO is a photoswitchable opsin that couples to Gi/o signaling cascades and is rapidly activated by pulsed blue light, switched off with amber light, and effective for repeated, prolonged, and reversible inhibition. PPO rapidly and reversibly inhibits glutamate, GABA, and dopamine release at presynaptic terminals. Furthermore, PPO alters reward behaviors in a time-locked and reversible manner invivo. These results demonstrate that PPO fills a significant gap in the neuroscience toolkit for rapid and reversible synaptic inhibition and has broad utility for spatiotemporal control of inhibitory GPCR signaling cascades.

Structural and optical characterization of NaBi1-x(WO4)2: X Sm3+phosphors for reddish orange light emitting applications

NaBi1-x(WO4)2: x Sm3+phosphors (x = 0.02, 0.04, 0.08, 0.10 and 0.20) were synthesized at 850° C via solid state reaction method. The crystal structure and phase analysis were performed using X-ray diffraction (XRD) technique and are isostructural with NaBi(WO4)2. The photoluminescence studies reveal that the phosphors exhibit excellent reddish- orange emission with short decay time of the order of millisecond on exciting with 404 nm. The obtained chromaticity coordinates (0.5903, 0.4023) are close to the Nichia corporation fabricated amber light emitting diode (LED) NSPAR 70BS. These results suggest the prepared phosphor to be a potential candidate for its use as reddish orange emitting material in white light emitting applications.

Relative light sensitivities of four retinal hemi-fields for suppressing the synthesis of melatonin at night

The magnitude of the stimulus to the biological clock will depend upon the distribution of circadian phototransduction circuits across the retinae and the spatial distribution of luminous stimuli in the environment. The present study compared nocturnal melatonin suppression for light exposures to the superior, inferior, nasal, and temporal retina in one eye independent of shading from the brow and the nose. The stimulus was a 40° diameter luminous disc, half of which was blue light (LED, λpeak = 470 nm) and the other amber light (LED, λpeak = 590 nm). Experimentally, the orientation of the bipartite disc was rotated to each of the four cardinal points of the visual field. A full, 40° blue disc was also employed by replacing the amber half-disc with another blue half-disc. The blue full- and half-discs always produced 100 photopic lx at the cornea. As hypothesized, nocturnal melatonin suppression was statistically greatest when the blue half-disc was delivered to the nasal hemi-field (35%); the other three hemi-fields were equally affected by the blue half-disc (≈20%). Melatonin suppression for the full-disc was 24%, which was not statistically different than the average suppression for the four hemi-fields of 27%.

LED-Induced Carotenoid Synthesis and Related Gene Expression in Brassica Microgreens

In this study, various ratios of combined red, blue, and amber light-emitting diodes (rbaLEDs) were investigated for their effect on the expression of carotenoid biosynthetic genes and carotenoid accumulation in eight Brassica microgreens. Total and individual (β-carotene, lutein, α-carotene, neoxanthin, and violaxanthin) carotenoids were increased 20-44 and 10-55%, respectively, under dose-dependent increasing amber-blue light and decreasing red in most microgreens. Lipophilic 2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power antioxidant activities were significantly increased under higher amber and blue light fractions, while oxygen radical absorbance capacity was generally decreased. Under rbaLED in mizuna (B. rapa) microgreens, the lycopene epsilon cyclase (LYCε) expression was 10-15-fold higher, which resulted in downstream accumulation of α-carotene and lutein. Lycopene beta cyclase (LYCβ) was not significantly changed, suggesting that β-carotene, violaxanthin and neoxanthin were mainly controlled by upstream phytoene synthase and branch-point LYCε. Increased beta-ring carotenoid hydroxylase (CHXβ) expression was also consistent with lutein accumulation. This study demonstrated for the first time that amber LED was involved in the regulatory mechanism of carotenoid biosynthesis, thus a potential novel approach to production of antioxidant-rich microgreens.

Intelligent Vehicular Traffic Signal Control for Vehicular AdHoc Networks

Current traffic regulator in remote is vehicle impelled, pre-coordinated, and webster’s technique, which produce more deferral at higher traffic. The chance of sending a keen and constant versatile traffic light regulator, which gets data from vehicles, for example, the position and speed of the vehicle, and then use this information to streamline the traffic light signal at the convergence for vehicle to vehicle(V2V) and vehicle to infrastructure(V2I) communication. The traffic board framework utilizing the AdHoc Ondemand Distance Vector (AODV) convention for VANET is sufficiently used in this work. It has been seen that practically all routes demand communication arrive at the target, a couple over significant distances with center vehicle thickness fizzled. Nonetheless, the load on the association starting from the unsophisticated transmission is gigantic. Therefore, it additionally prompts rapidly developing postponements and connection disappointment. A few trajectory answers don’t come through considering the way that telecomunication is as yet going on. This is a basic issue, particularly in city regions with high vehicle thickness. Based on the information in this paper, appropriate traffic signal control is developed to minimize the congestion at the intersections

Choice of the rational regimes of traffic light control for traffic and pedestrian flows

The method for the choice of rational regimes of traffic light control is developed based on the minimization of the number of violations the requirements of traffic light signals by pedestrians depending on the volume-capacity ratio of traffic lanes and control of vehicular queue on the approach to the stop-line. Assessment of rationality is carried out considering the simultaneous impact of such factors as roadway volume-capacity ratio, traffic light restrictive signal duration, the number of violations of the traffic rules by pedestrians, and maximal queue length of vehicles. The model of the change of the number of violations of the rules of crossing the roadway by pedestrians depending on the volume-capacity ratio of different intersection types is developed in this paper. The model of determining the maximal vehicular queue length before intersections depending on the volume-capacity ratio and the share of the restrictive signal on the lane in the control cycle is developed. Recommendations about the choice of rational regimes of traffic light control depending on traffic delay, planning parameters of the road network, and pedestrian behavior are proposed.

Design of Lighting Intelligent Control System Based on OpenCV Image Processing Technology

The high growth of vehicular travel in urban areas, in particular, requires a traffic control system that optimizes traffic flow efficiency. Traffic congestion can also occur by large de-lays in Red Light etc. The delay in lighting is difficult to code and does not rely on real traffic density. It follows that traffic controls are simulated and configured to better meet this rising demand. So, in order to avoid the traffic control problem, the Adaptive Intelligent Traffic Light control system (AITLCS) has been proposed based on OpenCV and Image processing technique. The system proposed is designed to ensure smooth and efficient traffic flow for daily life as well as emergency and public transportation safety. Based on the road density instead of the levels set the proposed system provides the timing for the traffic light signal so that a highly loaded side switched on over long periods compared with the other lanes. It can also be used at an intersection with traffic signs, which controls the traffic light signal at the intersection. If timers are smart to predict the exact time, the system is more efficient because it reduces the time spent on unintended green signal significantly. With the help of OpenCV software, this paper aims to have a signal management SMART solution that will be cost-effective at the end. The system consists of a camera facing a lane taking pictures of the route we want to travel and then the density of the pedestrian and vehicle is taken and compared with each image employing image processing. Such images are processed effectively to learn the density of traffic.

Exposure to Blue Wavelength Light Is Associated With Increases in Bidirectional Amygdala-DLPFC Connectivity at Rest.

Blue wavelength light has been used successfully as a treatment method for certain mood disorders, but, the underlying mechanisms behind the mood enhancing effects of light remain poorly understood. We investigated the effects of a single dose of 30 min of blue wavelength light (n = 17) vs. amber wavelength light (n = 12) exposure in a sample of healthy adults on subsequent resting-state functional and directed connectivity, and associations with changes in state affect. Individuals who received blue vs. amber wavelength light showed greater positive connectivity between the right amygdala and a region within the left dorsolateral prefrontal cortex (DLPFC). In addition, using granger causality, the findings showed that individuals who received blue wavelength light displayed greater bidirectional information flow between these two regions relative to amber light. Furthermore, the strength of amygdala-DLPFC functional connectivity was associated with greater decreases in negative mood for the blue, but not the amber light condition. Blue light exposure may positively influence mood by modulating greater information flow between the amygdala and the DLPFC, which may result in greater engagement of cognitive control strategies that are needed to perceive and regulate arousal and mood.

Real-time energy management of fuel cell hybrid electric buses: Fuel cell engines friendly intersection speed planning

In this paper, a novel fuel cell engines friendly real-time energy management is proposed, which considers the intersection speed planning to reduce frequent load change conditions in the process of driving. The main advantage of this energy management is that it can improve road transportation efficiency, promote the goal of minimum hydrogen consumption and extend the service life of the fuel cell engines. For the intersection speed planning method, the information of the vehicle in front of the driving route and the traffic signal light states are considered based on dynamic programming (DP). With the intersection speed planning, the corresponding control variable is applied for the model predictive control (MPC) based energy management when the bus is 100m away from the traffic light. The simulation results show that the equivalent hydrogen saving rate can improve by approximately 3.04% and reduce 3.4% idle working conditions compared with the MPC based without intersection speed planning energy management. The hardware in the loop test show that the vehicle speed can follow the target speed, and the equivalent hydrogen consumption error is within 2.5%, which meets the allowable error range.

Redesigning immunization supply chains: Results from three country analyses

IntroductionImmunization supply chains (iSC) are essential for ensuring access to vaccines that prevent diseases. Guinea, Madagascar, and Niger initiated iSC system design efforts to conduct analysis of alternative supply chain scenarios to identify areas for improvement. MethodologyKey stakeholders from Ministries of Health and immunization programs identified bottlenecks in the current iSC and prioritized five general design scenarios to model in each country. Scenarios included aspects of integration, changing supply chain levels and delivery frequency, ignoring administrative boundaries, and direct delivery. Primary and secondary data were collected and cleaned. Analysis was completed using Supply Chain Guru (Madagascar and Niger) and AnyLogistix (Guinea) modeling software to build a virtual representation of the iSC physical components and operating policies. ResultsModeling results were compared using both quantitative and qualitative criteria (total operating costs, cost per dose, cold chain capacity, risk of mishandling, logistics burden on healthcare workers, feasibility to implement, and equity). Using a Stop Light Analysis for user-friendly understanding of positive, negative or minimal impact on scenarios, cost savings were realized in most scenarios in Madagascar (except using autonomous aerial vehicles); proposed scenarios in Guinea increased costs or had minimal impact; in Niger, eliminating regional tiers reduced costs. Facility level cold chain was sufficient in all countries. Effect on qualitative indicators largely depended on the scenario and country context. DiscussionSimilarities in scenarios selected were seen across the three countries. Results suggest that efficiencies can be found through changes to the iSC design, but the benefits of each scenario must be considered in the country context. Results of the analysis do not provide “the right answer” but rather options and guidance which then must be grounded in the country context and used as evidence for decision making to ensure reliable availability of vaccines.

Methodology for Estimating the Effect of Traffic Flow Management on Fuel Consumption and CO2 Production: A Case Study of Celje, Slovenia

The manuscript discusses the investigation of vehicle flow in a predesignated junction by an appropriate traffic flow management with an effort to minimize fuel consumption, the production of CO2, an essential greenhouse gas (hereinafter referred to as GHG), and related transport costs. The particular research study was undertaken in a frequented junction in the city of Celje, located in the eastern part of Slovenia. The results obtained summarize data on consumed fuel and produced CO2 amounts depending on the type of vehicle, traffic flow mixture, traffic light signal plan, and actual vehicle velocity. These values were calculated separately for three different conditions of traffic flow management. Amounts of fuel consumed were experimentally investigated in real traffic situations, whereas CO2 production was calculated by applying the actual European standard entitled EN 16258:2012 associated with a guideline for measuring emission values, as well as by examining specific traffic flow parameters. The key objective of the manuscript is to present multiple scenarios towards striving to minimize environmental impacts and improve transport operation’s economic consequences when implementing proper traffic flow management. As for crucial findings, we quantified fuel consumption and CO2 emissions based on real data on the number and type of vehicles crossing the examined intersection and traffic light switching intervals. The results show that most of the CO2 was produced while waiting and in the accelerating phase in front of traffic lights, whereby in the running phase through the intersection, significantly less fuel was used. This study represents a mosaic fragment of research addressing endeavors to reduce CO2 production in urban transport. Following the experiments conducted, we can see a notable contribution towards reducing CO2 production with known and tested interventions in the existing transport infrastructure. A procedure embracing individual research steps may be deemed as an approach methodology dealing with traffic flow management with an aim to decrease the environmental and economic impacts of traffic and transport operation; this is where the novelty of the research lies.

A new way to “see” color

Sensory Perception Color perception is an important aspect of the way many organisms navigate their world. The ability to perceive color has thus far thought to depend on the presence of either eyes or minimally receptive cells containing opsin receptor genes. Ghosh et al. show that foraging Caenorhabditis elegans roundworms, which do not have eyes or opsins, can distinguish a blue color indicative of a toxin released by bacterial mats (see the Perspective by Neal and Vosshall). They suggest that the worms do this through the detection of the ratio between blue and amber light, a process dependent on at least two cellular stress-response genes. Different strains of C. elegans responded to different ratios, suggesting that this pathway plays an ecological role. Science , this issue p. [1059][1]; see also p. [995][2] [1]: /lookup/doi/10.1126/science.abd3010 [2]: /lookup/doi/10.1126/science.abg5201

C. elegans discriminates colors to guide foraging.

Color detection is used by animals of diverse phyla to navigate colorful natural environments and is thought to require evolutionarily conserved opsin photoreceptor genes. We report that Caenorhabditis elegans roundworms can discriminate between colors despite the fact that they lack eyes and opsins. Specifically, we found that white light guides C. elegans foraging decisions away from a blue-pigment toxin secreted by harmful bacteria. These foraging decisions are guided by specific blue-to-amber ratios of light. The color specificity of color-dependent foraging varies notably among wild C. elegans strains, which indicates that color discrimination is ecologically important. We identified two evolutionarily conserved cellular stress response genes required for opsin-independent, color-dependent foraging by C. elegans, and we speculate that cellular stress response pathways can mediate spectral discrimination by photosensitive cells and organisms-even by those lacking opsins.

Evaluasi Kinerja Alat Pemberi Isyarat Lalu Lintas (APILL) Menggunakan Metode Manual Kapasitas Jalan Indonesia 1997 Dan Webster

The development of transportation occurs along with the development of residents in an area. The impact caused a buildup of vehicles on the highway. Transportation growth is linearly related to the Traffic Light Signaling Tool (APILL). Giving a Traffic Giver Tool is one way to regulate traffic. The methods that can be used for the duration of the APILL include the 1997 Indonesian Road Capacity Manual Method and Webster. The location of the study was in the Simpang Statue area of Pangeran Diponegoro and Abdulrahman Saleh. The webster method is calculated based on vehicles that come randomly. The calculation of the webster method is used to calculate the average delay of a vehicle when approaching an intersection where this delay occurs due to the large number of vehicles entering compared to the vehicle coming out of the intersection. the use of this webser method aims to be able to produce the optimum cycle time at each intersection. The Indonesian Road Capacity Manual Method (MKJI 1997) is a manual for road traffic calculations but cannot be used to analyze networks. This intersection obtains a degree of saturation average of ≥ 0.75, meaning that this intersection experiences a buildup of vehicles or congestion. The capacity and volume of vehicles in each intersection are inversely proportional. The intersection capacity can only accommodate around 2500 vehicles / hour but when on the field there are 7200 vehicles / hour. This makes APILL not work in each intersection. Simpang Statue of Pangeran Diponegoro and Abdulrahman Saleh is included in the F service (low speed blocked flow). The duration of the APILL time is not the same every day because the vehicle volume changes in each hour so that it is designed several plan APILL in the intersection. To overcome this kind of incident can be assisted by officers from the Police or the Semarang City Transportation Agency. Until now the APILL method still uses the Indonesian Road Capacity Manual 1997. Compared to the Webster method, the data needed is very minimal or incomplete. The results of the APILL time duration obtained using the 1997 Indonesia Jalan Capacity Manual method differ from the duration of time in the field and generally the results of calculations the duration of time obtained from this method added 10% of the calculation results and applied in the field.

Narrow‐spectrum artificial light silences female fireflies (Coleoptera: Lampyridae)

AbstractThe rapid spread of artificial light at night (ALAN) poses myriad problems for nocturnal biodiversity.Bioluminescent taxa that communicate via glowing lures, warning signals, or courtship advertisements may have their signals obscured by artificial illumination, unless the added light is spectrally tuned to reduce its impact.Previous research has demonstrated that broad‐spectrum white light inhibits the production of courtship advertisements by male firefly beetles, yet the impact of varying wavelengths of artificial light on both members of the courtship dialogue is largely unknown.We exposed courting pairs ofPhotinus obscurellusfireflies to five colours of downwelling illumination, at two intensities, and recorded changes in male flash rate and flash intensity, female responsiveness, and the flash pattern composition of both sexes.All artificial light treatments significantly suppressed courtship activity.Bright amber light had the greatest impact, suggesting that ALAN which most overlaps the spectrum of firefly bioluminescence will most disrupt firefly courtship.Our findings contradict similar investigations of non‐bioluminescent taxa and raise concerns about the possibility of a universal standard for ecologically sustainable ALAN.

Daily Morning Blue Light Therapy for Post-mTBI Sleep Disruption: Effects on Brain Structure and Function.

Background: Mild traumatic brain injuries (mTBIs) are associated with novel or worsened sleep disruption. Several studies indicate that daily morning blue light therapy (BLT) is effective for reducing post-mTBI daytime sleepiness and fatigue. Studies demonstrating changes in brain structure and function following BLT are limited. The present study's purpose is to identify the effect of daily morning BLT on brain structure and functional connectivity and the association between these changes and self-reported change in post-mTBI daytime sleepiness.Methods: A total of 62 individuals recovering from a mTBI were recruited from two US cities to participate in a double-blind placebo-controlled trial. Eligible individuals were randomly assigned to undergo 6 weeks of 30 min daily morning blue or placebo amber light therapy (ALT). Prior to and following treatment all individuals completed a comprehensive battery that included the Epworth Sleepiness Scale as a measure of self-reported daytime sleepiness. All individuals underwent a multimodal neuroimaging battery that included anatomical and resting-state functional magnetic resonance imaging. Atlas-based regional change in gray matter volume (GMV) and region-to-region functional connectivity from baseline to post-treatment were the primary endpoints for this study.Results: After adjusting for pre-treatment GMV, individuals receiving BLT had greater GMV than those receiving amber light in 15 regions of interest, including the right thalamus and bilateral prefrontal and orbitofrontal cortices. Improved daytime sleepiness was associated with greater GMV in 74 ROIs, covering many of the same general regions. Likewise, BLT was associated with increased functional connectivity between the thalamus and both prefrontal and orbitofrontal cortices. Improved daytime sleepiness was associated with increased functional connectivity between attention and cognitive control networks as well as decreased connectivity between visual, motor, and attention networks (all FDR corrected p < 0.05).Conclusions: Following daily morning BLT, moderate to large increases in both gray matter volume and functional connectivity were observed in areas and networks previously associated with both sleep regulation and daytime cognitive function, alertness, and attention. Additionally, these findings were associated with improvements in self-reported daytime sleepiness. Further work is needed to identify the personal characteristics that may selectively identify individuals recovering from a mTBI for whom BLT may be optimally beneficial.

Blue-wavelength light therapy for post-traumatic brain injury sleepiness, sleep disturbance, depression, and fatigue: A systematic review and network meta-analysis.

This review aimed to determine the efficacy of blue-wavelength light therapy (BWLT) for post-traumatic brain injury (TBI) sleepiness, sleep disturbance, depression, and fatigue. Pubmed, Scopus, Web of Science, Cochrane Library, Academic Search Complete, and CINAHL. Included trials were randomized controlled trials (RCTs) of BWLT in adults with a history of TBI. Outcomes of interest included sleepiness, sleep disturbance, depression, or fatigue. Two reviewers independently screened the searched items, selected the trials, extracted the data, and rating the quality of trials. We aggregated the data using a random-effect, frequentist network meta-analysis (NMA). We searched the databases on July 4, 2020. This review included four RCTs of 117 patients with a history of TBI who were randomized to received BWLT, amber light therapy (ALT), or no light therapy (NLT). Moderate-quality evidence revealed that: i) BWLT was significantly superior to NLT in reducing depression (SMD = 0.81, 95% CI = 0.20 to 1.43) ii) BWLT reduced fatigue at a significantly greater extent than NLT (SMD = 1.09, 95% CI = 0.41 to 1.76) and ALT (SMD = 1.00, 95% CI = 0.14 to 1.86). Low-quality evidence suggested that BWLT reduced depression at a greater extent than ALT (SMD = 0.57, 95% CI = 0.04 to 1.10). Low-quality evidence found that the dropout rates of those receiving BWLT and ALT were not significantly different (RR = 3.72, 95% CI = 0.65 to 21.34). Moderate-quality evidence suggests that BWLT may be useful for post-TBI depression and fatigue.