Climatological characteristics of sea breeze parameters at Chennai

Several sea breeze parameters such as time of onset, withdrawal, duration, depth, variation with height, direction etc. have been derived and studied for Chennai city and Chennai AP observatories in this study, which has been based on a large data base for the period March-October,1969-83. The monthly and sub monthly values of several sea breeze parameters have been derived. By invoking the concept of superposed epoch analysis the important role played by sea breeze in modulating diurnal variation of surface temperature and relative humidity has been established. The sea breeze at Chennai has been shown to be shallow with a depth of under 1 km. Modal directions of sea breeze and its normal speed have been derived.

Regional difference in prefrontal oxygenation prior to and during overground walking in humans: A wearable multi-channel NIRS study

Using wireless multi-channel near-infrared spectroscopy, regional difference in cortical activity over the prefrontal cortex (PFC) was examined prior to and during overground walking, and in response to changes in speed and cognitive demand. Oxygenated-hemoglobin concentration (Oxy-Hb) as index of cortical activity in ventrolateral PFC (VLPFC), dorsolateral PFC (DLPFC), and frontopolar cortex (FPC) was measured in 14 subjects, while heart rate was measured as estimation of exercise intensity in 6 subjects. The impact of mental imagery on prefrontal Oxy-Hb was also explored. On both sides, Oxy-Hb in VLPFC, DLPFC, and lateral FPC was increased prior to the onset of normal speed walking, whereas Oxy-Hb in medial FPC did not respond prior to walking onset. During the walking, Oxy-Hb further increased in bilateral VLPFC, whereas Oxy-Hb was decreased in DLPFC and lateral and medial FPC. Increasing walking speed did not alter the increase in Oxy-Hb in VLPFC but counteracted the decrease in Oxy-Hb in DLPFC (but not in lateral and medial FPC). Treadmill running evoked a greater Oxy-Hb increase in DLPFC (n = 5 subjects). Furthermore, increasing cognitive demand during walking, by deprivation of visual feedback, counteracted the decrease in Oxy-Hb in DLPFC and lateral and medial FPC, but it did not affect the increase in Oxy-Hb in VLPFC. Taken together, the profound and localized Oxy-Hb increase is a unique response for the VLPFC. The regional heterogeneity of the prefrontal Oxy-Hb responses to natural overground walking was accentuated by increasing walking speed or cognitive demand, suggesting functional distinction within the PFC.

A Dual-Task Paradigm Using the Oral Trail Making Test While Walking to Study Cognitive-Motor Interactions in Older Adults

Objective: With aging, gait becomes more dependent on executive functions, especially on switching abilities. Therefore, cognitive-motor dual-task (DT) paradigms should study the interferences between gait and switching tasks. This study aimed to test a DT paradigm based on a validated cognitive switching task to determine whether it could distinguish older-old adults (OO) from younger-old adults (YO).Methods: Sixty-five healthy older participants divided into 29 younger-old (<70 years) and 36 older-old (≥70 years) age groups were evaluated in three single-task (ST) conditions as follows: a cognitive task including a processing speed component [Oral Trail Making Test part A (OTMT-A)], a cognitive task including a switching component [Oral Trail Making Test part B (OTMT-B)], and a gait evaluation at normal speed. They were also evaluated under two DT conditions, i.e., one associating gait with OTMT-A and the other associating gait with OTMT-B. Cognitive and gait performances were measured. The comparison of cognitive and gait performances between condition, logistic regression, and receiver operating characteristic (ROC) analyses were performed.Results: The cognitive and gait performances were differently affected by the different conditions (i.e., ST, DT, OTMT-A, and OTMT-B). The OTMT-B produced higher interference on gait and cognitive performances. Moreover, a higher number of errors on the OTMT-B performed while walking was associated with the older-old age group.Conclusion: Using validated cognitive flexibility tasks, this DT paradigm confirms the high interference between switching tasks and gait in older age. It is easily implemented, and its sensitivity to age may highlight its possible usefulness to detect cognitive or motor declines.

Impact of Weight Carriage on Joint Kinematics in Asian Elephants Used for Riding

Background: Elephants in Thailand have changed their roles from working in the logging industry to tourism over the past two decades. In 2020, there were approximately 2700 captive elephants participating in activities such as riding and trekking. During work hours, riding elephants carry one or two people in a saddle on the back with a mahout on the neck several hours a day and over varying terrain. A concern is that this form of riding can cause serious injuries to the musculoskeletal system, although to date there have been no empirical studies to determine the influence of weight carriage on kinematics in elephants. Methods: Eight Asian elephants from a camp in Chiang Mai Province, Thailand, aged between 21 and 41 years with a mean body mass of 3265 ± 140.2 kg, were evaluated under two conditions: walking at a normal speed without a saddle and with a 15% body mass load (saddle and two persons plus additional weights). Gait kinematics, including the maximal angles of fore- and hindlimb joints, were determined using a novel three-dimensional inertial measurement system with wireless sensors. Results: There were no statistical differences between movement angles and a range of motion of the fore- and hindlimbs, when an additional 15% of body mass was added. Conclusion: There is no evidence that carrying a 15% body mass load causes significant changes in elephant gait patterns. Thus, carrying two people in a saddle may have minimal effects on musculoskeletal function. More studies are needed to further test longer durations of riding on different types of terrain to develop appropriate working guidelines for captive elephants. Nevertheless, elephants appear capable of carrying significant amounts of weight on the back without showing signs of physical distress.

Analyzing Inundation Impacts on Transportation Network - The Case Study of Vadodara City

Inundation and related problems have become more uncontrollable all over the world leading to unexpected deaths, severe damage to infrastructure, and epidemics like conditions every year. A great number of cities in India have reported a series of heavy hazardous precipitation events during past few years. The immediate effects observed of floods specifically in urban areas are on the transportation network leading to its disruption. Most of the studies on transportation susceptibility including immediate and shortly after inundation events consider topographic properties along with supply and demand side of transportation system to access the disruption caused. In response to such events, this study aims to provide framework to access the susceptibility to urban road network due to inundation events. An integrated framework between meteorological information, land use functions, and hydrodynamic model simulated in HEC-RAS with rainfall event with 1-in-100 year is used for the analysis of the impacts being generated on the transportation infrastructure by such event. A critical map and index is developed to identify affected road length susceptible to flood. It has been observed that more than 40 percent of road length across the network has been affected by such unpredictable events. Also, there is a significant decrease in average speed of movement as compared to average normal speed observed on the normal days.

COOPERATIVE LOCALISATION USING IMAGE SENSORS IN A DYNAMIC TRAFFIC SCENARIO

Localisation is one of the key elements in navigation. Especially due to the development in automated driving, precise and reliable localisation becomes essential. In this paper, we report on different cooperation approaches in visual localisation with two vehicles driving in a convoy formation. Each vehicle is equipped with a multi-sensor platform consisting of front-facing stereo cameras and a global navigation satellite system (GNSS) receiver. In the first approach, the GNSS signals are used as excentric observations for the projection centres of the cameras in a bundle adjustment, whereas the second approach uses markers on the front vehicle as dynamic ground control points (GCPs). As the platforms are moving and data acquisition is not synchronised, we use time dependent platform poses. These time dependent poses are represented by trajectories consisting of multiple 6 Degree of Freedom (DoF) anchor points between which linear interpolation takes place. In order to investigate the developed approach experimentally, in particular the potential of dynamic GCPs, we captured data using two platforms driving on a public road at normal speed. As a baseline, we determine the localisation parameters of one platform using only data of that platform. We then compute a solution based on image and GNSS data from both platforms. In a third scenario, the front platform is used as a dynamic GCP which can be related to the trailing platform by markers observed in the images acquired by the latter. We show that both cooperative approaches lead to significant improvements in the precision of the poses of the anchor points after bundle adjustment compared to the baseline. The improvement achieved due to the inclusion of dynamic GCPs is somewhat smaller than the one due to relating the platforms by tie points. Finally, we show that for an individual vehicle, the use of dynamic GCPs can compensate for the lack of GNSS data.

Full gaze contingency provides better reading performance than head steering alone in a simulation of prosthetic vision

The visual pathway is retinotopically organized and sensitive to gaze position, leading us to hypothesize that subjects using visual prostheses incorporating eye position would perform better on perceptual tasks than with devices that are merely head-steered. We had sighted subjects read sentences from the MNREAD corpus through a simulation of artificial vision under conditions of full gaze compensation, and head-steered viewing. With 2000 simulated phosphenes, subjects (n = 23) were immediately able to read under full gaze compensation and were assessed at an equivalent visual acuity of 1.0 logMAR, but were nearly unable to perform the task under head-steered viewing. At the largest font size tested, 1.4 logMAR, subjects read at 59 WPM (50% of normal speed) with 100% accuracy under the full-gaze condition, but at 0.7 WPM (under 1% of normal) with below 15% accuracy under head-steering. We conclude that gaze-compensated prostheses are likely to produce considerably better patient outcomes than those not incorporating eye movements.

THE EFFECTS OF INCREASING INSOLE STIFFNESS ON FOOT AND ANKLE MECHANICS IN WALKING GAIT

The energetic pattern of the foot–ankle system is critical in human walking gait. While some of the mechanical energy was dissipated due to foot segment deformation in walking stance phase. Increasing footwear insole bending stiffness was reported to restrict foot segment bending behavior and this was reported to reduce foot segment energy dissipation. While little is known whether increasing footwear insole bending stiffness would alter foot–ankle system mechanical work generation and absorption patterns. Two healthy subjects (one female, one male; age [Formula: see text] years, height [Formula: see text][Formula: see text]cm, weight [Formula: see text][Formula: see text]kg) participated in this study and they were asked to walk at self-selected normal speed with the same footwear (Nike Free RN Flyknit, 2017) in two different insole stiffness conditions: (i) normal shoe insole (NSI); (ii) carbon fiber insole (CFI). Paired sample [Formula: see text]-test was conducted between NSI and CFI for all outcome measures. No statistically significant differences in the outcome variables were found between the two insole conditions. While foot segment positive work and mechanical work ratio were 45.54% and 68.43% higher in CFI than in NSI condition, respectively; foot negative work was 25.02% lower in CFI than in NSI condition. However, ankle joint positive work and work ratio were around more than 10% higher in NSI than in CFI condition, and ankle peak positive power in NSI was 23.93% higher than in CFI condition. Additionally, foot–ankle system overall positive work and mechanical work ratio were both similar between NSI and CFI conditions. The findings indicate increasing footwear insole bending stiffness may influence foot segment and ankle joint energetic patterns in walking stance phase. And the mechanical energy generation compensatory mechanism may exist between foot segment and ankle joint. Specifically, a decreased foot segment energy generation tended to result in a higher amount of ankle joint positive work and peak power generation. This will be beneficial for maintaining a relatively consistent foot–ankle system overall energy generation and work ratio in response to altered insole stiffness and foot segment work during gait.

Differences Between Autistic and Non-autistic Adults in the Recognition of Anger From Dynamic Expressions Remain After Controlling for Alexithymia.

A burgeoning literature suggests that alexithymia, and not autism, is responsible for the difficulties with static emotion recognition that are documented in the autistic population. Here we investigate whether alexithymia can also account for difficulties with dynamic facial expressions. Autistic and control adults (N=60) matched on age, gender, non-verbal reasoning ability and alexithymia, completed an emotion recognition task, which employed dynamic point light displays of emotional facial expressions that varied in speed and spatial exaggeration. The ASD group exhibited significantly lower recognition accuracy for angry, but not happy or sad, expressions with normal speed and spatial exaggeration. The level of autistic, and not alexithymic, traits was a significant predictor of accuracy for angry expressions with normal speed and spatial exaggeration.