Semi-streaming algorithms for submodular matroid intersection.

While the basic greedy algorithm gives a semi-streaming algorithm with an approximation guarantee of 2 for the unweighted matching problem, it was only recently that Paz and Schwartzman obtained an analogous result for weighted instances. Their approach is based on the versatile local ratio technique and also applies to generalizations such as weighted hypergraph matchings. However, the framework for the analysis fails for the related problem of weighted matroid intersection and as a result the approximation guarantee for weighted instances did not match the factor 2 achieved by the greedy algorithm for unweighted instances.Our main result closes this gap by developing a semi-streaming algorithm with an approximation guarantee of 2 + ε for weighted matroid intersection, improving upon the previous best guarantee of 4 + ε . Our techniques also allow us to generalize recent results by Levin and Wajc on submodular maximization subject to matching constraints to that of matroid-intersection constraints. While our algorithm is an adaptation of the local ratio technique used in previous works, the analysis deviates significantly and relies on structural properties of matroid intersection, called kernels. Finally, we also conjecture that our algorithm gives a ( k + ε ) approximation for the intersection of k matroids but prove that new tools are needed in the analysis as the structural properties we use fail for k ≥ 3 .

Current practice in handling and reporting needle biopsies: A hospital-based survey.

CONTEXT: Core-needle biopsy (CNB) is a minimally invasive screening and diagnostic tool which provides intact tissue fragments for histopathological examination. AIMS: This study was conducted to review the current practices of handling and reporting CNBs performed for core-needle biopsies from four organ systems which are frequently encountered in our institution. These include breast, prostate, soft tissues, and lymph nodes. SETTINGS AND DESIGN: This was a retrospective study conducted at a tertiary care hospital. MATERIALS AND METHODS: CNB reports of breast, prostate, soft tissue, and lymph nodes were accessed and categorized based on the site of biopsy, number, and average length of the cores. The CNB reports were categorized into diagnostic or nondiagnostic. In case of diagnosis of malignancy, reports were recorded as structured or nonstructured reports. STATISTICAL ANALYSIS USED: Fisher's exact test and Chi-square tests were applied to check the significance of the results obtained on comparing the number of cores and size of cores with the outcome of report. RESULTS: Out of 16,300 surgical pathology specimens received, 400 were CNBs comprising breast (n = 211), prostate (n = 108), soft tissue (n = 50), and lymph node (n = 31). Majority of the CNBs had 2-5 cores and the size of the core was ≥0.5 cm, which accounted for most of the reports which were diagnostic. There was a lack of clinical and radiological detail in many of the cases. Out of the malignant cases diagnosed, structured reports were given in 30% of breast, 79.3% of prostate, 41.7% soft tissue, and 60% of lymph node needle biopsies. CONCLUSIONS: The audit helped to identify areas of improvement in CNB services.

Monoarticular Poncet Disease after Pulmonary Tuberculosis: A Rare Case Report and Review of Literature.

INTRODUCTION: Tuberculosis is a major health problem worldwide, more so in Asian countries and especially India. Being a communicable disease, it can affect the lives of many people. Tuberculosis has varied manifestations and can affect almost every part of the human body. Pulmonary tuberculosis is the most common form. Poncet disease (tuberculous rheumatism) is a polyarticular arthritis that occurs during acute tuberculosis infection in which no mycobacterial involvement can be found or no other known cause of polyarthritis is detected. CASE PRESENTATION: We describe an atypical presentation of active pulmonary tuberculosis with monoarticular Poncet disease of the right knee in a 24-year-old woman. DISCUSSION: The diagnosis of Poncet disease is mainly clinical with exclusion of other causes. It generally presents as an acute or subacute form; however, chronic forms have been described in the literature.