Evaluation of missing data mechanisms in two and three dimensional incomplete tables

The analysis of incomplete contingency tables is a practical and an interesting problem. In this paper, we provide characterizations for the various missing mechanisms of a variable in terms of response and non-response odds for two and three dimensional incomplete tables. Log-linear parametrization and some distinctive properties of the missing data models for the above tables are discussed. All possible cases in which data on one, two or all variables may be missing are considered. We study the missingness of each variable in a model, which is more insightful for analyzing cross-classified data than the missingness of the outcome vector. For sensitivity analysis of the incomplete tables, we propose easily verifiable procedures to evaluate the missing at random (MAR), missing completely at random (MCAR) and not missing at random (NMAR) assumptions of the missing data models. These methods depend only on joint and marginal odds computed from fully and partially observed counts in the tables, respectively. Finally, some real-life datasets are analyzed to illustrate our results, which are confirmed based on simulation studies

Cropping duration and non-rhizomorphic mycelial phenotype of Pleurotus djamor woody1 co-segregate in the hybrid progenies

Crop duration of the cultivated Pleurotus spp. is 45 to 50 days. P. djamor isolate woody-1 was collected as natural selection and was found to be short cropping duration variety with total cropping duration of 30 days but it is less palatable. It produced very thin, loose and non-rhizomorphic mycelia appearing light white color. Whereas, other commercial Pleurotus varieties such as P. florida and P. djamor MDU1 are long crop duration varieties and palatable producing thick, compact and rhizomorphic mycelia with bright white color. Co-segregation of non-rhizomorphic mycelial phenotype and short cropping duration trait of P. djamor woody- 1 in hybrid progenies was evaluated. Hybrid strains viz., H2W12 and H2W14 have thin, loose and non-rhizomorphic mycelium and they produced primordia in 9-10 days after spawning with total cropping duration of 29-32 days. Whereas, hybrid strain namely Pf1W2 has thick, compact and rhizomorphic mycelial phenotype and it produced primordia in 20 days after spawning with the total cropping duration of 47 days. This study indicated that genes governing short cropping duration and non-rhizomorphic mycelial pattern were tightly linked and co-segregated in the progenies. Thus, non-rhizomorphic mycelial phenotype of P. djamor woody1 can be used as a phenotypic marker for selection of hybrid cultivar having short cropping duration with other desired agronomic traits in future breeding strategy

Low switching power neuromorphic perovskite devices with quick relearning functionality

In the quest to reduce energy consumption, there is a growing demand for technology beyond silicon as electronic materials for neuromorphic artificial intelligence devices. Equipped with the criteria of energy efficiency and excellent adaptability, organohalide perovskites can emulate the characteristics of synaptic functions in the human brain. In this aspect, this study designs and develops CsFAPbI3-based memristive neuromorphic devices that can switch at low power and show larger endurance by adopting the powder engineering methodology. The neuromorphic characteristics of the CsFAPbI3-based devices exhibit an ultra-high paired-pulse facilitation index for an applied electric stimuli pulse. Moreover, the transition from short-term to long-term memory requires ultra-low energy with long relaxation times. The learning and training cycles illustrate that the CsFAPbI3-based devices exhibit faster learning and memorization process owing to their larger carrier lifetime compared to other perovskites. The results provide a pathway to attain low-power neuromorphic devices that are synchronic to the human brain's performance