S4 is a general-purpose, distributed, scalable, partially fault-tolerant, pluggable platform that allows programmers to easily develop applications for processing continuous unbounded streams of data. Keyed data events are routed with affinity to Processing Elements (PEs), which consume the events and do one or both of the following: (1) emit one or more events which may be consumed by other PEs, (2) publish results. The architecture resembles the Actors model [1], providing semantics of encapsulation and location transparency, thus allowing applications to be massively concurrent while exposing a simple programming interface to application developers. In this paper, we outline the S4 architecture in detail, describe various applications, including real-life deployments. Our design is primarily driven by large scale applications for data mining and machine learning in a production environment. We show that the S4 design is surprisingly flexible and lends itself to run in large clusters built with commodity hardware.

Arthropathies and joint deformities in patients with severe hemophilia result in prolonged immobilization, reduced physical activity, and predispose them for osteoporosis. This can lead to an increasing tendency of bone fragility and fractures in patients after trivial trauma. The aim of this study was to find out (i) the prevalence of osteoporosis in hemophilia patients and (ii) the association of osteoporosis with hemophilic arthropathy and related restricted physical activity. In this case-control study, 50 consecutive severe hemophilia patients aged between 20 and 50 years were evaluated for osteoporosis with measurement of bone mass density (BMD) by a DEXA scan and values were compared with that of 50 sex matched normal healthy controls. Major joints of the limbs were evaluated to determine the extent of joint damage and related disability. Forty-two patients had severe hemophilia A and 8 patients severe hemophilia B (efficient factor activity < 0.01 U/ml). BMD values (gms/ cm 2 ) of lumbar spine and left hip of the patients were significantly lower than that of controls (0.825 vs. 0.939; P < 0.0001 and 0.725 vs. 0.938; P < 0.0001, respectively). The incidence of osteoporosis (T score: 22.5 or more) was significantly higher in hemophiliacs. Incidence of fractures in adult life was also significantly higher in hemophiliacs compared to controls (12% vs. 0%). There was statistically significant correlation between joint evaluation scores and BMD of hip, but not with that of the lumbar spine. There was no correlation between Hepatitis-C virus status and BMD of any site. This shows that development of osteoporosis is a significant problem in patients with severe hemophilia in this country. Hence appropriate preventive measures such as early treatment and adequate mobilization, exercises, encouragement to participate in sporting activities, early assessment of bone density, and administration of anti-osteoporotic therapy is recommended. Am. J. Hematol. 82:453-457, 2007. V V C 2007 Wiley-Liss, Inc.

We study a number of natural language decipherment problems using unsupervised learning. These include letter substitution ciphers, character code conversion, phonetic decipherment, and word-based ciphers with relevance to machine translation. Straightforward unsupervised learning techniques most often fail on the first try, so we describe techniques for understanding errors and significantly increasing performance.

Intracranial haemorrhage (ICH) is a common cause of morbidity and mortality in haemophilic patients all over the world. From 1995 to 2004, we have investigated 37 patients with 43 episodes of ICH at our Comprehensive Haemophilia Care Center from a total of 600 registered patients. Diagnosis of ICH in the patients was confirmed by clinical, haematological and computed tomographic imaging data. Three patients died despite replacement therapy while one child who had a ventriculo-atrial shunt for acute hydrocephalus also died before further intervention. One of the four patients who died also had severe aplastic anaemia for 6 years in addition to severe haemophilia. Detailed history obtained from 143 families with haemophilia attending the Genetic Diagnosis Clinic at our Center showed a positive history of cerebral bleed in 39 episodes in 37 patients. Sixteen families gave a history of death in the family of haemophilic patients due to ICH, while in the remaining 21 families, the patients had survived the episode after treatment elsewhere. However, the ICH was not confirmed by image data in these cases. The treatment protocols were also not available in these cases. Conservative factor replacement therapy 100% correction for 3 days followed by 50-60% correction for 7 days) coupled with the epsilon amino caproic acid, the antifibrinolytic agent at least for 30 days led to a mortality (10.8%) similar to that of the western countries and almost no morbidity. Surgery was not required in any of these patients except in one elderly patient with HIV infection on antiretroviral therapy.