Incremental Entity Resolution from Linked Documents

In many government applications we often find that information about entities, such as persons, are available in disparate data sources such as passports, driving licences, bank accounts, and income tax records. Similar scenarios are commonplace in large enterprises having multiple customer, supplier, or partner databases. Each data source maintains different aspects of an entity, and resolving entities based on these attributes is a well-studied problem. However, in many cases documents in one source reference those in others; e.g., a person may provide his driving-licence number while applying for a passport, or vice-versa. These links define relationships between documents of the same entity (as opposed to inter-entity relationships, which are also often used for resolution). In this paper we describe an algorithm to cluster documents that are highly likely to belong to the same entity by exploiting inter-document references in addition to attribute similarity. Our technique uses a combination of iterative graph-traversal, locality-sensitive hashing, iterative match-merge, and graph-clustering to discover unique entities based on a document corpus. A unique feature of our technique is that new sets of documents can be added incrementally while having to re-resolve only a small subset of a previously resolved entity-document collection. We present performance and quality results on two data-sets: a real-world database of companies and a large synthetically generated `population' database. We also demonstrate benefit of using inter-document references for clustering in the form of enhanced recall of documents for resolution.Comment: 15 pages, 8 figures, patented wor

Predicting Remaining Useful Life using Time Series Embeddings based on Recurrent Neural Networks

We consider the problem of estimating the remaining useful life (RUL) of a system or a machine from sensor data. Many approaches for RUL estimation based on sensor data make assumptions about how machines degrade. Additionally, sensor data from machines is noisy and often suffers from missing values in many practical settings. We propose Embed-RUL: a novel approach for RUL estimation from sensor data that does not rely on any degradation-trend assumptions, is robust to noise, and handles missing values. Embed-RUL utilizes a sequence-to-sequence model based on Recurrent Neural Networks (RNNs) to generate embeddings for multivariate time series subsequences. The embeddings for normal and degraded machines tend to be different, and are therefore found to be useful for RUL estimation. We show that the embeddings capture the overall pattern in the time series while filtering out the noise, so that the embeddings of two machines with similar operational behavior are close to each other, even when their sensor readings have significant and varying levels of noise content. We perform experiments on publicly available turbofan engine dataset and a proprietary real-world dataset, and demonstrate that Embed-RUL outperforms the previously reported state-of-the-art on several metrics.Comment: Presented at 2nd ML for PHM Workshop at SIGKDD 2017, Halifax, Canad

A case series on drug induced hyponatremia: uncommon adverse effect of commonly used drugs

Older patients suffering from depression and psychosis have markedly increased since last decade. So, has the use of antidepressants and antipsychotics. The prevalence of hyponatremia due to these drugs is common in general as well as psychiatric practice. It may also lead to life threatening morbidity and mortality. Loss of renal function, polypharmacy, dementia and other conditions of advanced age can either exacerbate the severity of hyponatremia or mask its onset. In this case series, total four cases were reported of hyponatremia and drugs causing it were escitalopram, quetiapine, tianeptine and oxcarbazepine. Due to polypharmacy, a chance of hyponatremia was more in these patients. Patients received infusion of hypertonic saline with salt added diet to treat hyponatremia. Symptoms of hyponatremia were improved after the treatment. In all four cases, WHO and Naranjo’s causality assessment revealed ‘possible’ causal relationship with the prescribed drug. Prescribers should be aware of such adverse effect due to these drugs

Cutaneous manifestations of anti retroviral therapy used for post-exposure prophylaxis

Health care workers are at increased risk of needle stick injuries. Blood borne diseases that could be transmitted by such an injury include HIV, Hepatitis B, HCV and many others. Post exposure prophylaxis should be immediately started within 72 hours and should be continued for 28 days. Currently two Nucleoside Reverse Transcriptase Inhibitors (NRTIs) are given along with one NNRTI (Non- Nucleoside reverse Transcriptase Inhibitor) including Efavirenz or Nevirapine. Multiple adverse effects have been reported with all the Anti- Retroviral Therapies including various cutaneous manifestations. A 22-year-old intern doctor studying in tertiary hospital of Ahmedabad had a needle stick injury with a needle contaminated with blood of HIV positive patient. Post Exposure prophylaxis was started within 72 hours consisting of fixed dose regimen of Tenofovir disprodoxil sulphate, Efavirenz and lamivudine. He was started with the drug within 2 hours and was prescribed one drug per day for next 27 days. On 22nd day he started having rash on his body which started on palms and soles. On 23rd day he saw severe facial edema along with edema on lips and rash spreading to other parts of the body. He was diagnosed with Hypersensitivity reaction and angioedema due to ART drug therapy. He was instructed to stop ART medications and was given antihistaminic for the symptoms. Patient's angioedema was relieved in 2-3 days and rash disappeared after 4-5 days. As he had already finished 23 days of therapy he was instructed to discontinue the drugs. No recurrence of rash or angioedema was noted. This case points out the severity of side effects in the normal healthy people taking ART as Post Exposure Prophylaxis. Apart from cutaneous manifestations, angioedema is a very grievous condition which doctors should always have lower threshold for diagnosis. Early diagnosis can prevent further complications. ART drugs have many complications and these patients should have intensive regular monitoring while on treatment. Also, proper education is required for needle cut injuries in health care workers