Fletcher-Turek Model Averaged Profile Likelihood Confidence Intervals

We evaluate the model averaged profile likelihood confidence intervals proposed by Fletcher and Turek (2011) in a simple situation in which there are two linear regression models over which we average. We obtain exact expressions for the coverage and the scaled expected length of the intervals and use these to compute these quantities in particular situations. We show that the Fletcher-Turek confidence intervals can have coverage well below the nominal coverage and expected length greater than that of the standard confidence interval with coverage equal to the same minimum coverage. In these situations, the Fletcher-Turek confidence intervals are unfortunately not better than the standard confidence interval used after model selection but ignoring the model selection process

Rehabilitation of irrigation systems in Sri Lanka: A literature review

Rehabilitation / Irrigation systems / Water management / Tank irrigation / Modernization / Research / Investment / Farmer participation / Sri Lanka / Gal Oya Project / Uda Walawe

APPLICATIONS OF CHEMICALLY MODIFIED ELECTRODES

An overview Is presented of the major areas of applications ofchemically modified electrods. No attempt has been made tocomprehensively review the literature. Rather, successful examplesfrom each area have been used to illustrate the principles involved

A PRELIMINARY INVESTIGATION OF THE SHODHANA (DETOXIFICATION) OF ROOTS OF PLUMBAGO INDICA L. IN AYURVEDA

Plumbago indica L. (Plumbaginaceae) is a medicinal herb, credited with a number of therapeutic properties. It is widely used in Sri Lankan traditional medicine and in Ayurveda. In Sri Lanka, Ayurveda formulations which incorporate the roots of P. indica L. are prepared using commercially available air dried material after subjecting it to a detoxification with limewater prepared from commercially available milk of lime. The detoxification process is referred to as “Shodhanaâ€. According to the Ayurveda, this process is done to remove toxicity associated with the roots and, it can be surmised that it is done to remove toxicity associated with plumbagin, the predominant toxic naphthoquinone in P. indica L.. Shodhana of roots results in a deep maroon coloured extract arising from the calcium salt of plumbagin. Here, we report a qualitative and quantitative study of the Shodhana of roots of P. indica L. using Ultra Violet-Visible spectrophotometric and chromatographic methods to give a scientific basis for this process. A method for the quantitative extraction of plumbagin from root samples was optimized. A calibration curve for plumbagin in hexane was developed using the absorption values at 258 nm. The plumbagin content of 8.7 ± 0.1 mg/g in a fresh root sample was lowered by 19.4% to 7.0 ± 0.1 mg/g upon subjecting to Shodhana. It was found that a commercial dried root sample of P. indica L. root contained a much lower level (0.55 ± 0.05 mg/g) of plumbagin. To better understand the changes in the level of plumbagin in roots of P. indica L. during drying, a study was carried out by drying the root samples for five weeks subjecting them to analysis periodically by TLC and Ultra Violet-Visible spectrophotometric methods. The amount of plumbagin (8.6 ± 0.1 mg/g) present in fresh untreated roots at the beginning of the study was reduced by 62.7% to 3.2 ± 0.1 mg/g after one week. There was no measurable change in the plumbagin level thereafter up to week 5. The amount of plumbagin in dried roots can be further reduced by Shodhana. The total reduction of plumbagin by drying and Shodhana was 87.7%. Our results show that Shodhana of the fresh undried roots does not reduce the plumbagin content substantially, and that air drying followed by Shodhana is the most effective method to reduce the plumbagin content to a non-toxic level, supporting the currently used processing method

EFFECT OF ETHYL ACETATE SOLUBLE PROANTHOCYANIDINS FROM COCOS NUCIFERA L. INFLORESCENCE ON PROGESTERONE AND OESTROGEN LEVELS IN FEMALE RATS

The immature inflorescence of Cocos nucifera L. variety aurantiaca is used by Ayurvedic and traditional medical practitioners for the treatment of menorrhagia in Sri Lanka. We have previously reported the extraction, purification and characterization of ethyl acetate soluble proanthocyanidins (EASPA) in the inflorescence of Cocos nucifera L. EASPA obtained from immature Cocos nucifera L. (var. aurantiaca) inflorescence was evaluated for its effect on the reproductive hormonal levels of female rats. EASPA (0.33 mg/day) dissolved in water was administered orally to female rats for 28 consecutive days. At the end of the study period, oestrogen and progesterone levels were measured and compared with the control group (water). Statistical analysis was performed with one-way ANOVA, followed by student T test using Minitab 17.0 software. The length of the reproductive cycle was 4.44±0.15 days and 4.56±0.15 days for the control and test group rats, respectively. No significant changes were noticed in the length of the cycle nor were there any difference in vaginal cytology in test and control group rats. There was no significant difference in the estrogen level between control and test group animals. However, there was a highly significant increase in progesterone levels of the test group as compared to the control (P 0.001). This result suggests a possible mode of action to explain the use of coconut inflorescence in controlling menorrhagia in traditional medicine in Sri Lanka

Differential effects of Epigallocatechin-3-gallate containing supplements on correcting skeletal defects in a Down syndrome mouse model

SCOPE: Down syndrome (DS), caused by trisomy of human chromosome 21 (Hsa21), is characterized by a spectrum of phenotypes including skeletal abnormalities. The Ts65Dn DS mouse model exhibits similar skeletal phenotypes as humans with DS. DYRK1A, a kinase encoded on Hsa21, has been linked to deficiencies in bone homeostasis in DS mice and individuals with DS. Treatment with Epigallocatechin-3-gallate (EGCG), a known inhibitor of Dyrk1a, improves some skeletal abnormalities associated with DS in mice. EGCG supplements are widely available but the effectiveness of different EGCG-containing supplements has not been well studied. METHODS AND RESULTS: Six commercially available supplements containing EGCG were analyzed, and two of these supplements were compared with pure EGCG for their impact on skeletal deficits in a DS mouse model. The results demonstrate differential effects of commercial supplements on correcting skeletal abnormalities in Ts65Dn mice. Different EGCG-containing supplements display differences in degradation, polyphenol content, and effects on trisomic bone. CONCLUSION: This work suggests that the dose of EGCG and composition of EGCG-containing supplements may be important in correcting skeletal deficits associated with DS. Careful analyses of these parameters may lead to a better understanding of how to improve skeletal and other deficits that impair individuals with DS

Dual roles for LUBAC signaling in thymic epithelial cell development and survival

Thymic epithelial cells (TECs) form a unique microenvironment that orchestrates T cell differentiation and immunological tolerance. Despite the importance of TECs for adaptive immunity, there is an incomplete understanding of the signalling networks that support their differentiation and survival. We report that the linear ubiquitin chain assembly complex (LUBAC) is essential for medullary TEC (mTEC) differentiation, cortical TEC survival and prevention of premature thymic atrophy. TEC-specific loss of LUBAC proteins, HOIL-1 or HOIP, severely impaired expansion of the thymic medulla and AIRE-expressing cells. Furthermore, HOIL-1-deficiency caused early thymic atrophy due to Caspase-8/MLKL-dependent apoptosis/necroptosis of cortical TECs. By contrast, deficiency in the LUBAC component, SHARPIN, caused relatively mild defects only in mTECs. These distinct roles for LUBAC components in TECs correlate with their function in linear ubiquitination, NFκB activation and cell survival. Thus, our findings reveal dual roles for LUBAC signaling in TEC differentiation and survival