Policy Gradients for CVaR-Constrained MDPs

We study a risk-constrained version of the stochastic shortest path (SSP) problem, where the risk measure considered is Conditional Value-at-Risk (CVaR). We propose two algorithms that obtain a locally risk-optimal policy by employing four tools: stochastic approximation, mini batches, policy gradients and importance sampling. Both the algorithms incorporate a CVaR estimation procedure, along the lines of Bardou et al. [2009], which in turn is based on Rockafellar-Uryasev's representation for CVaR and utilize the likelihood ratio principle for estimating the gradient of the sum of one cost function (objective of the SSP) and the gradient of the CVaR of the sum of another cost function (in the constraint of SSP). The algorithms differ in the manner in which they approximate the CVaR estimates/necessary gradients - the first algorithm uses stochastic approximation, while the second employ mini-batches in the spirit of Monte Carlo methods. We establish asymptotic convergence of both the algorithms. Further, since estimating CVaR is related to rare-event simulation, we incorporate an importance sampling based variance reduction scheme into our proposed algorithms

A further remark on dynamic programming for partially observed markov processes

In (Stochastic Process. Appl. 103 (2003) 293), a pair of dynamic programming inequalities were derived for the 'separated'ergodic control problem for partially observed Markov processes, using the 'vanishing discount'argument. In this note, we strengthen these results to derive a single dynamic programming equation for the same

ROLE OF AGNIKARMA IN THE MANAGEMENT OF TRIGGER FINGER

Although in ancient times, Agnikarma practice has been very less but the last ten years have seen a remarkable rise in the efficiency of Agnikarma practice. This has been possible due to a combination of valuable researches and conferences carried out all over the globe. And thats the reason why most of the Ayurvedic Shalya Tantra practitioners use Agnikarma as a healing mechanism for most of the human diseases. Although modern surgical procedures are effective for curing diseases but the complications that arise out of such procedures are equally fatal and deadly. However in recent times it has been observed that such diseases can be cured by Agnikarma without undertaking any surgical procedure hence Agnikarma is proved to be a boon for curing such diseases. Trigger finger, a disease is commonly seen in professions which involve frequent movement of fingers e.g. surgeons, typist, barbour, soldiers, farmer etc. As the reference of Acharya Sushruta suggests the disease trigger finger can be correlated with Snaya Asthi Sandhi Aashrita Vikara. So the patient should be kept under Agnikarma therapy upto a satisfactory level of relief from pain and hence in this study a case of trigger finger was treated by Agnikarma for a period of 30 days. In this period 4 sittings was administered at intervals of 7 days giving a complete relief from symptoms. After completion of Agnikarma, the patient was followed up and observed for recurrence for 3 months

A NOVEL METHOD FOR VRANA SHODHANA & ROPANA USING KSHARAJALA

Indians have paid enough attention to discover the therapeutic effects of plants and herbs as medicinal agents in many diseases. Plants contain Alkaloids and various other chemical substances which form the base for many medical preparations. Most of the drugs used are derived from the natural world through the experiments of earlier civilization. Ksharajala is an innovative concept used for management of Infected & chronic Wounds and ulcers. This Ksharajala was prepared with the help of Apamargakshara & distilled water in 1:100 proportion. It can be used in number of open wounds & ulcers. This Ksharajala is prepared similar to the Hima kalpana preparation. There are number of dressing materials given by Sushruta e.g. Pichu, Kawalika, Plota and Vikeshika or Varti, Kashaya, Kwatha, Rasakriya, Swarasa, Lepa and Hima. Ksaharajala as a dressing material which can be used as for deep & broader wounds & ulcers. In the present study preparation of Ksharajala, advantages, indications, disadvantages, sterilization, storage, standardization were observed for simple & safest parasurgical practice

INNOVATION OF KSHARAPLOTA (MEDICATED GAUZE) IN THE MANAGEMENT OF VRANA (ULCER)

Indians have paid enough attention to discover the therapeutically effects of plants and herbs as medicinal agents in many diseases. Plants contain Alkaloids and various other chemical substances which form the base for many medical preparations. Most of the drugs used are derived from the natural world through the experiments of earlier civilization. Ksharaplota (medicated gauze) is an innovative concept used for management of infected and chronic wounds and ulcers. This Ksharaplota (medicated gauze) was prepared with the help of Snuhikshira (latex of Euphorbia neriifolia Linn.), Apamargakshara (ash of Achyranthes aspera L.) and Haridra (Curcuma longa L.). Single coating of the above drugs are given to the Plota (gauze). It can be used to heal wounds and ulcers. This Ksharaplota is prepared similarly with basic concept of Ksharasutra preparation. There are number of dressing materials given by Sushruta e.g. Pichu (cloth), Kawalika, Plota (gauze) and Vikeshika or Varti (wick). Among that we selected Plota as a dressing material which can be used as for deep and broader wounds and ulcers. In the present study preparation of Ksharaplota, advantages, indications, disadvantages, sterilization, storage, standardization were observed for simple and safest parasurgical practice

EFFECT OF COUNSELING FOR CONSTIPATION IN PRIMARY SCHOOL CHILDREN: A SURVEY STUDY

Constipation is a very common problem which affects large number of school going population of children. The most of the gastroenterologist, pediatricians and proctologist encounter with this problem routinely. Socio-economic factors play significant role towards the prevalence of disease. The dietary habits & life style pattern also leads constipation in children. This article presented a survey study based on primary school children suffered with constipation. The study revealed causes of constipation mainly associated with social & daily routine activities. The 83% of affected students were found to have bad dietary habits. The 56 % of affected children were found to possess lack of outdoor sports activity. Counseling to students, teachers and parents help to change their diet pattern and living habits in natural way. The present study also suggests guideline or rules to be adopted for curing problem of constipation in primary school children

ROLE OF AGNIKARMA THERAPY IN THE MANAGEMENT OF KADARA (CORN): A CASE REPORT

Kadara (corn) is initially painless in condition but with its progress, it may become painful. In modern science, corn is being treated by using anti inflammatory drugs, corn cap, saliciylic acid and excision. Even today there is no satisfactory and permanent treatment available for corn because of its high recurrence tendency. According to Ayurveda, ˜Kadara can be correlated with the condition of corn. Aacharya Sushrut has advised Agnikarma (cauterization) for Kadara. Hence, in this study corn (Kadara) was treated by Agnikarma with Panchadhatu Shalaka (instrument made of 5 metals) in a systematic manner for a duration of 15 days with intervals of 5 days in 3 sittings. Here, we have applied two types of Agnikarma. i.e. Pratisaran (flat type of cauterization) and Bindu (dotted type of cauterization) which were used in combination with application of Tilatailam (sesame oil) for better results. This combination therapy provided cured management, which is observed in the present case study. The patient was followed upto 6 months for observation of recurrence

ROLE OF AGNIKARMA WITH ELECTRIC CAUTERY IN CHARMAKILA W. S. R. TO WART- A CASE DISCUSSION

Agnikarma Chikitsa was at peak level in Sushruta period but its use was declined gradually in modern era due to lack of availability of instruments and also the therapy was not easily acceptable by patient so in the present case study discussion we have made attempt on the disease Charmakila with the help of electric cauterization which is nothing but advanced version of ancient Agnikarma therapy. In present case study observation, efficacy of electric cauterization therapy shows minimum invasive parasurgical method in Charmakila (wart). One patient was treated on OPD basis in a minor OT of Ayurved college hospital Rahuri. Treatment was well tolerated by patient without complication during the therapy and post operative period. Hence, use of electric cautery as an Agnikarmas Dahanaupakarana in Charmakila is a best option with minimum trauma, easily acceptable by patient and surgeon in their fast day-to-day life