Väsymyksen vaikutus ajosuoriutumiseen liukkaalla tiellä

Tavoitteet Kuljettajan väsymys vaikuttaa keskeisesti niin ajokykyyn kuin onnettomuusriskiinkin. Ajo-olosuhteet taas määrittävät sen miten kuljettajat kokevat väsymyksen ajon aikana. Haastavissa olosuhteissa ajaminen saattaa lisätä väsyneiden kuljettajien tarkkaavaisuutta ajotapahtumaa kohtaan, mutta tämä voi lisätä myös kognitiivista taakkaa ja aiheuttaa näin lisää väsymystä. Tämän tutkimuksen tavoitteena on selvittää miten liukkaalla tiellä ajaminen vaikuttaa yhdessä univajeesta johtuvan väsymyksen kanssa kuljettajan ajosuoriutumiseen. Menetelmät Kaksitoista miespuolista koehenkilöä (i’iltään 19–21) ajoivat ajosimulaattorissa 52.5 km matkan neljässä eri asetelmassa (päivä- ja yöaikaan sekä kuivalla ja liukkaalla tiellä). Subjektiivista uneliaisuutta mitattiin Karolinska Sleepiness Scalen avulla ja fysiologista väsymystä silmänräpäysten pituuden perusteella elektro-okulografiaa käyttäen. Kuljettajien ajosuoriutumista arvioitiin kolmella muuttujalla: auton sivuttaissijainnin keskipoikkeama ajoradalla, ohjausliikkeiden amplitudien keskiarvo ja ohjausliikkeiden huippunopeuden keskiarvo. Ajosession jälkeen koehenkilöt ajoivat liikennekartiopujottelutehtävän, jossa onnistumista arvioitiin erikseen. Tulokset Liukkaalla tiellä ajaminen paransi univajeesta kärsivien kuljettajien ajosuoriutumista kaikilla kolmella muuttujalla mitattuna. Kolmisuuntainen yhdysvaikutus kuljettajan tilan, tieolosuhteiden ja ajan välillä oli merkitsevä vain subjektiivisen uneliaisuuden kohdalla. Univajeisten kuljettajien uneliaisuus lisääntyi nopeammin liukkaalla tiellä, mutta tämä ei vaikuttanut heidän ajosuoriutumiseensa. Johtopäätökset Haastavissa olosuhteissa ajaminen voi lisätä jo valmiiksi väsyneiden kuljettajien väsymystä, mutta muutokset suorituskyvyssä voivat näkyä vasta viipeellä. Suuret yksilölliset erot niin väsymys- kuin ajo-olosuhdevasteissa vaativat lisätutkimusta.Objectives Fatigue is a major factor affecting driving performance and traffic accident risk. Driving conditions influence how people experience fatigue while driving. Driving in demanding conditions may increase vigilance in tired drivers; however, it may also increase cognitive load and become an additional source of fatigue. The current study investigated how driving on a slippery road interacts with fatigue caused by sleep deprivation and how it influences driving performance. Methods Twelve male participants (aged 19–21) drove 52.5 km in a driving simulator in four different conditions (day vs night and dry vs slippery road). Subjective sleep-related fatigue was measured with the Karolinska Sleepiness Scale and physiological fatigue in blink durations with electro-oculography. Three measures were used for driver performance: standard deviation of lateral position, mean steering wheel movement amplitude and mean steering wheel movement peak velocity. After each driving session, participants negotiated a cone track. The success rate for this task was analysed separately. Results Driving on slippery roads improved performance in all three performance metrics in sleep-deprived drivers. The three-way interaction between driver condition, road condition and time-on-task was significant for subjective sleep-related fatigue but not for performance. Sleep-deprived drivers became increasingly sleepy over time when driving in slippery conditions; however, this did not negatively affect their performance. Conclusions Driving in demanding weather conditions can increase the fatigue experienced by drivers; however, this change may not be initially detectable in performance. Large individual variability in response to both fatigue and driving conditions requires further research

High-index glass for the products of ophthalmologic optics

The results of development of high-index glass for the products of ophthalmologic optics on the basis of the systems Li2O – RO – B2O3– SiO2and K2O – TiO2– SiO2are presented. It is shown that the formation of complexes [TiO4/2O] 2– K2 + in glass of the system K2O – TiO2– SiO2interferes with the formation of the chromophorecenters Fe 2+ – O – Ti 4+ and allows to receive colorless glass at amount of TiO2to 30 mol.%. The compositions of glass with a refractive index 1.65 and 1.70 at density no more than 2.91 g/cm 3 are developed. It allows to recommend them for the production of the facilitated lenses with a high optical force

Building Distributed File Systems on Commercial Cloud Storage Services

With the increase in bandwidths available for internet users, cloud storage services have emerged to offer home users an easy way to share files and extend the storage space available for them. Most systems offer a limited free storage quota and combining these resources from multiple providers could be intriguing to cost-oriented users. In this study, we will implement a virtual file system that utilizes multiple different commercial cloud storage services (Dropbox, Google Drive, Microsoft OneDrive) to store its data. The data will be distributed among the different services and the structure of the data will be managed locally by the file system. The file system will be run in user space using FUSE and will use APIs provided by the cloud storage services to access the data. Our goal is to show that it is feasible to combine the free space offered by multiple services into a single easily accessible storage medium. Building such a system requires making design choices in multiple problem areas ranging from data distribution and performance to data integrity and data security. We will show how our file system is designed to address these requirements and will then conduct several tests to measure and analyze the level of performance provided by our system in different file system operation scenarios. The results will also be compared to the performance of using the distinct cloud storage services directly without distributing the data. This will help us to estimate the overhead or possible gain in performance caused by the distribution of data. It will also help us to locate the bottlenecks of the system. Finally, we will discuss some of the ways that could be used to improve the system based on test results and examples from existing distributed file systems

Direct confocal acquisition of fluorescence from X-gal staining on thick tissue sections

X-gal staining is a common procedure used in the histochemical monitoring of gene expression by light microscopy. However, this procedure does not permit the direct confocal acquisition of images, thus preventing the identification of labelled cells on the depth (Z) axis of tissue sections and leading sometimes to erroneous conclusions in co-localization and gene expression studies. Here we report a technique, based on X-gal fluorescence emission and mathematically-based optical correction, to obtain high quality fluorescence confocal images. This method, combined with immunofluorescence, makes it possible to unequivocally identify X-gal-labelled cells in tissue sections, emerging as a valuable tool in gene expression and cell tracing analysis

Sleepy drivers on a slippery road : A pilot study using a driving simulator

Sleepy drivers have problems with keeping the vehicle within the lines, and might often need to apply a sudden or hard corrective steering wheel movement. Such movements, if they occur while driving on a slippery road, might increase the risk of ending off road due to the unforgiving nature of slippery roads. We tested this hypothesis. Twelve young men participated in a driving simulator experiment with two counterbalanced conditions; dry versus slippery road x day (alert) versus night (sleepy) driving. The participants drove 52.5 km on a monotonous two-lane highway and rated their sleepiness seven times using the Karolinska Sleepiness Scale. Blink durations were extracted from an electrooculogram. The standard deviation of lateral position and the smoothness of steering events were measures of driving performance. Each outcome variable was analysed with mixed-effect models with road condition, time-of-day and time-on-task as predictors. The Karolinska Sleepiness Scale increased with time-on-task (p < 0.001) and was higher during night drives (p < 0.001), with a three-way interaction suggesting a small increased sleepiness with driving time at night with slippery road conditions (p = 0.012). Blink durations increased with time-on-task (p < 0.01) with an interaction between time-of-day and road condition (p = 0.040) such that physiological sleepiness was lower for sleep-deprived participants in demanding road conditions. The standard deviation of lateral position increased with time-on-task (p = 0.026); however, during night driving it was lower on a slippery road (p = 0.025). The results indicate that driving in demanding road condition (i.e. slippery road) might further exhaust already sleepy drivers, although this is not clearly reflected in driving performance.Peer reviewe

Regulation of oxygen sensing by ion channels

O2 sensing is of critical importance for cell survival and adaptation of living organisms to changing environments or physiological conditions. O2-sensitive ion channels are major effectors of the cellular responses to hypoxia. These channels are preferentially found in excitable neurosecretory cells (glomus cells of the carotid body, cells in the neuroepithelial bodies of the lung, and neonatal adrenal chromaffin cells), which mediate fast cardiorespiratory adjustments to hypoxia. O2- sensitive channels are also expressed in the pulmonary and systemic arterial smooth muscle cells where they participate in the vasomotor responses to low O2 tension (particularly in hypoxic pulmonary vasoconstriction). The mechanisms underlying O2 sensing and how the O2 sensors interact with the ion channels remain unknown. Recent advances in the field give different support to the various current hypotheses. Besides the participation of ion channels in acute O2 sensing, they also contribute to the gene program developed under chronic hypoxia. Gene expression of T-type calcium channels is upregulated by hypoxia through the same hypoxiainducible factor-dependent signaling pathway utilized by the classical O2-regulated genes. Alteration of acute or chronic O2 sensing by ion channels could participate in the pathophysiology of human diseases, such as sudden infant death syndrome or primary pulmonary hypertension

AllSight: A Low-Cost and High-Resolution Round Tactile Sensor with Zero-Shot Learning Capability

Tactile sensing is a necessary capability for a robotic hand to perform fine manipulations and interact with the environment. Optical sensors are a promising solution for high-resolution contact estimation. Nevertheless, they are usually not easy to fabricate and require individual calibration in order to acquire sufficient accuracy. In this letter, we propose AllSight, an optical tactile sensor with a round 3D structure potentially designed for robotic in-hand manipulation tasks. AllSight is mostly 3D printed making it low-cost, modular, durable and in the size of a human thumb while with a large contact surface. We show the ability of AllSight to learn and estimate a full contact state, i.e., contact position, forces and torsion. With that, an experimental benchmark between various configurations of illumination and contact elastomers are provided. Furthermore, the robust design of AllSight provides it with a unique zero-shot capability such that a practitioner can fabricate the open-source design and have a ready-to-use state estimation model. A set of experiments demonstrates the accurate state estimation performance of AllSight