Deep Vein Thrombosis of the Left Leg: A Case of May-Thurner Syndrome

A 56-year-old woman presented with gradually worsening shortness of breath associated with dull left leg pain over 5 days. She denied any recent travel, recent surgeries or immobilization. CT pulmonary angiography and CT venography revealed multiple bilateral pulmonary emboli and extensive left pelvic and left lower extremity deep vein thromboses. Contrast-enhanced CT showed that the right common iliac artery crossed the left common iliac vein and compressed it externally, indicative of May–Thurner syndrome. Catheter-directed thrombolysis of the left lower extremity was performed and heparin infusion was started. The patient also underwent left iliac vein balloon angioplasty with stenting and infra-renal inferior vena cava filter placement via the jugular approach to prevent further embolization

Hybrid Energy Management System Consisting of Battery and Supercapacitor for Electric Vehicle

This paper is mainly focused on Hybrid Energy Management System (HEMS) consisting of Battery (BT) and Super capacitor (SC). Two energy sources connected in with same DC link in parallel manner with the help of Bidirectional DC-DC converter, which is used to separate control of power flow of each source. Here Permanent magnet dc motor (PMDC) motor used as a load and speed control of PMDC motor can be done by PWM method for this purpose chopper circuit is used. Input of chopper circuit is DC link and output of the chopper is given to PMDC motor. This method of energy management gives power splitting between two sources based on State of Charge (SOC) of each individual source during different state of vehicle such as acceleration, constant running and deceleration. Improved filter-based power splitting techniques is implemented. Three acceleration reference points were taken for power splinting at different SOC levels of both energy sources. Objective of this proposed method is best use of both the sources i.e. battery and supercapacitor and maximum use of supercapacitor energy at the time of transient conditions. Battery supply energy during normal running condition or very less load condition. Hence during transient condition SC directly react with system and gives peak power requirement, so stress on battery is reduces hence lifetime of battery is increase, also power available during braking is store in SC and battery, so independence of Electric Vehicle (EV) is increases. Because of less peak power requirement, batteries with less peak output power is used so it is reduced size and cost of batteries. Matlab- Simulink software is used for simulation and also small scale hardware is also implemented of proposed method

Hybrid Energy Management System Consisting of Battery and Supercapacitor for Electric Vehicle

This paper is mainly focused on Hybrid Energy Management System (HEMS) consisting of Battery (BT) and Super capacitor (SC). Two energy sources connected in with same DC link in parallel manner with the help of Bidirectional DC-DC converter, which is used to separate control of power flow of each source. Here Permanent magnet dc motor (PMDC) motor used as a load and speed control of PMDC motor can be done by PWM method for this purpose chopper circuit is used. Input of chopper circuit is DC link and output of the chopper is given to PMDC motor. This method of energy management gives power splitting between two sources based on State of Charge (SOC) of each individual source during different state of vehicle such as acceleration, constant running and deceleration. Improved filter-based power splitting techniques is implemented. Three acceleration reference points were taken for power splinting at different SOC levels of both energy sources. Objective of this proposed method is best use of both the sources i.e. battery and supercapacitor and maximum use of supercapacitor energy at the time of transient conditions. Battery supply energy during normal running condition or very less load condition. Hence during transient condition SC directly react with system and gives peak power requirement, so stress on battery is reduces hence lifetime of battery is increase, also power available during braking is store in SC and battery, so independence of Electric Vehicle (EV) is increases. Because of less peak power requirement, batteries with less peak output power is used so it is reduced size and cost of batteries. Matlab- Simulink software is used for simulation and also small scale hardware is also implemented of proposed method

An impact of gap acceptance on road safety: A critical systematic review

An uncontrolled intersection is a critical area for crashes that depends on macroscopic traffic parameters. While the intersection is the potential of the center of crashes due to inappropriate decision of driver. Therefore, the study focuses on the effect of the gap acceptance parameter for the safety of drivers at an uncontrolled intersection. To examine, a systematic review of the literature is implemented to understand the different parameters, their impact, and models developed by the researchers. Additionally, it is demonstrated that the crashes are highly affected by the gap acceptance and the different models are formed to estimate the critical gap for different road sections under homogeneous and heterogeneous traffic conditions. However, it is not possible to definitively conclude the best model to evaluate the gap acceptance factor but can be preferred to reduce the severity of crashes. Nonetheless, most studies remain inconclusive, there is an emerging trend in the literature suggesting the increase of the crash risk at an uncontrolled intersection. Lastly, it is most important to mention the model suitability based on empirical studies commenced under the strong limitations. Consequently, there is a need for research in this area to correlate the gap acceptance with road safety to reduce the severity of accidents to improve the existing transportation system

Behavioral Characteristics of Pedestrian Flow on Stairway at Railway Station

India has witnessed higher level of mobility at urban as well as intercity segments due to improvisation of socio-economic conditions in last two decades. Even though, majority of the intercity travel is made by road based modes, number of passengers traveling by railways is significant on certain highly industrialized corridors. Collection and dispersal of passengers on railway platforms take place through stairways and foot over bridges. Design of these vital elements needs to incorporate the behavior of pedestrian flow to ensure desired level of service as well as safety in case of emergency. As reported in literature, pedestrian flow characteristics are influenced by number of attributes of pedestrian like age, gender, physical dimensions, luggage carried, group size, activity while walking, purpose in addition to the other attributes such as space availability, direction of movement and schedule of train as well. Very limited efforts are made in India to study pedestrian flow behavior in this context. Fluctuations in pedestrian flow depends on schedule of arrival and departure of the train, particularly during the peak hours as there is large passenger flow in short interval of time. Due to limited capacity of pedestrian facility, especially staircases, desired speed cannot be achieved by the pedestrian while walking in crowd with luggage. Higher walking speed is reported on downstairs than upstairs with reduction in speed with increase in pedestrian density. Most of the pedestrian facilities are designed by rule of thumb, especially stairways, largely governed by ideal pedestrian behavior. However behavior of individual pedestrian and hence flow at rail transit stations are dynamic on stairways depending on the factors mentioned above. Present study attempts to highlight the results of the study carried out on pedestrian flow behavior at Vadodara railway station in the state of Gujarat, India. Total 3411 number of pedestrian data are extracted by employing videographic technique. Flow models of speed- flow, speed-density and flow-density are developed to illustrate behaviour of pedestrian stream on stairways of different dimension

Impact of Train Schedule on Pedestrian Movement on Stairway at Suburban Rail Transit Station in Mumbai, India

Pedestrian flow takes place in confined environment on stairways under the influence of composition, direction of movement, and schedule of trains. During peak-period, alighting and boarding rate is quite high resulting in very high pedestrian movement from one platform to the other to catch the next train at interchange stations. The transfer of passengers from railway platforms through common undivided stairways becomes difficult, uncomfortable, and unsafe at times when pedestrian flow reaches the capacity level. Understanding of criteria defining quality of flow that affect the effectiveness of facilities like stairways in handling the pedestrian traffic is vital for planning and designing of such facilities to ensure the desired level of service as well as safety in case of emergency. The present paper is based on the study of pedestrian movement on stairways at busy suburban rail transit interchange station at Dadar in Mumbai, India. Pedestrian movements are captured through videography at two stairways and the effect of bidirectional movement on average walking speed is analyzed. The ascending flow in small proportion is found to be more influential in causing speed reduction on undivided stairways. The outcome of the study is useful for capacity and level of service analysis while planning and designing the transit station stairways

Gastric siderosis: An under-recognized and rare clinical entity

The increased deposition of iron in gastric mucosa is known as gastric siderosis. It is believed that the only regulated step of the iron metabolism cycle occurs during absorption in the small intestine. Once this system becomes overwhelmed due to either local or widespread iron levels, then iron can be absorbed very quickly by a passive concentration-dependent mechanism. This excess iron is initially stored in the liver but later can be found in the pancreas, heart and joints. Excess iron is not expected to deposit in the gastric mucosa. This gastric deposition has been found in association with hemochromatosis, oral iron medications, alcohol abuse, blood transfusions, hepatic cirrhosis and spontaneous portacaval shunt with esophageal varices. The precise mechanism of this iron deposition in gastric epithelial and stromal cells is still not well understood; thus, identification of iron in gastric mucosa raises many questions. On histology, the pattern of deposition is variable, and recognition of the pattern is often useful to choose the appropriate workup for the patient and to diagnose and possibly treat the cause of iron overload. In this article, we have described a well-referenced review of this rare clinical entity with different histological patterns, diagnostic tests and the clinical significance of the different patterns of iron deposition

Gastric siderosis: An under-recognized and rare clinical entity

The increased deposition of iron in gastric mucosa is known as gastric siderosis. It is believed that the only regulated step of the iron metabolism cycle occurs during absorption in the small intestine. Once this system becomes overwhelmed due to either local or widespread iron levels, then iron can be absorbed very quickly by a passive concentration-dependent mechanism. This excess iron is initially stored in the liver but later can be found in the pancreas, heart and joints. Excess iron is not expected to deposit in the gastric mucosa. This gastric deposition has been found in association with hemochromatosis, oral iron medications, alcohol abuse, blood transfusions, hepatic cirrhosis and spontaneous portacaval shunt with esophageal varices. The precise mechanism of this iron deposition in gastric epithelial and stromal cells is still not well understood; thus, identification of iron in gastric mucosa raises many questions. On histology, the pattern of deposition is variable, and recognition of the pattern is often useful to choose the appropriate workup for the patient and to diagnose and possibly treat the cause of iron overload. In this article, we have described a well-referenced review of this rare clinical entity with different histological patterns, diagnostic tests and the clinical significance of the different patterns of iron deposition

Supraclavicular block evaluation in oncoorthopedic patients under general anesthesia using perfusion index: A prospective cohort study

Background: Supraclavicular brachial plexus blocks (SCBPB) are routinely placed prior to anaesthetic induction for post-operative pain relief after prolonged orthopaedic oncosurgery, since patients are required to remain awake for sensorimotor evaluation of block. If the window period after surgery but before anesthesia-reversal is employed for administering SCBPB, it bestows the quadruple advantage of being painless, not augmenting surgical bleed, longer post-operative analgesia and reduced opioid-related side effects. The problem spot is assessing SCBPB-efficacy under general anesthesia. Methods: This prospective, single-centric, observational cohort study included 30 patients undergoing upper limb orthopaedic oncosurgery under general anesthesia. Perfusion index (PI) was assessed using two separate units of Radical-7™ finger pulse co-oximetry devices simultaneously in both the upper limbs and PI ratios calculated. Skin temperature was noted. Results: After successful block, PI values in blocked limb suddenly increased after 5 min, progressively increasing for next 10 min, whereas PI failed to increase further above that attained post anaesthetic-induction in unblocked limb. PI values in the blocked limb were 4.32, 4.49, 4.95, 7.25, 7.71, 7.90, 7.94, 7.89, and 7.93 at 0, 2, 3, 5, 10, and 15 min post block-institution at reversal and 2 min, 5 min post-reversal, respectively. PI ratios at 2, 3, 5, 10, and 15 min post block-administration in the blocked limb, taking PI at local anaesthetic injection as denominator were 1.04, 1.15, 1.67, 1.78, and 1.83, respectively. Correlation between PI and skin temperature in the blocked limb gave a repeated measures correlation coefficient of 0.79. Conclusion: Monitoring trends in PI and PI-ratio in the blocked limb is a quantitative, non-invasive, inexpensive, simple, effective technique to monitor SCBPB-onset in anaesthetised patients