Natural language processing (NLP) has recently gained much attention for representing and analyzing human language computationally. It has spread its applications in various fields such as machine translation, email spam detection, information extraction, summarization, medical, and question answering etc. In this paper, we first distinguish four phases by discussing different levels of NLP and components of N atural L anguage G eneration followed by presenting the history and evolution of NLP. We then discuss in detail the state of the art presenting the various applications of NLP, current trends, and challenges. Finally, we present a discussion on some available datasets, models, and evaluation metrics in NLP.

Background: It is well established that both micro and macro vascular complications of type 2 diabetes mellitus add significantly to the morbidity and mortality of the disease. Their prevention and early detection is of the utmost importance to reduce the burden on patients health as well as on the health system. Apart from conventional methods, newer techniques like measurement of serum magnesium can help in their detection and its prevention. Aim: To study the relation of serum magnesium with complications of type 2 diabetes mellitus. Materials & Methods: It was an observational prospective study including 80 patients of diagnosed cases of type 2 diabetes mellitus. We divided the study subject according to presence of a complication and compared serum magnesium levels in respective complications. Results: Out of 80 study subjects, 16 (20%) subjects had retinopathy. Out of them 15 (93%) subjects had hypomagnesemia. 5 (6%) subjects had nephropathy, out of which 4 (80%) had hypomagnesaemia. 4 (5%) patients had diabetic ketoacidosis or hyperosmolar hyperglycaemic non ketotic coma, out of which 3 (60%) had hypomagnesaemia. 55 (68%) patients did not have any complications, out of which only 12 (21%) had hypomagnesaemia. Conclusion: Hypomagnesaemia correlated with the presence of complications in type 2 diabetes mellitus.