Memory-Efficient Adaptive Optimization

Adaptive gradient-based optimizers such as Adagrad and Adam are crucial for achieving state-of-the-art performance in machine translation and language modeling. However, these methods maintain second-order statistics for each parameter, thus introducing significant memory overheads that restrict the size of the model being used as well as the number of examples in a mini-batch. We describe an effective and flexible adaptive optimization method with greatly reduced memory overhead. Our method retains the benefits of per-parameter adaptivity while allowing significantly larger models and batch sizes. We give convergence guarantees for our method, and demonstrate its effectiveness in training very large translation and language models with up to 2-fold speedups compared to the state-of-the-art

Collision tumor of the thyroid: follicular variant of papillary carcinoma and squamous carcinoma

BACKGROUND: Collision tumors of the thyroid gland are a rare entity. We present a case of a follicular variant of papillary carcinoma and squamous carcinoma in the thyroid. To the best of our knowledge, this is the first documentation of a collision tumor with a papillary carcinoma and a squamous carcinoma within the thyroid gland. The clinicopathological features and immunohistochemical profile are reported. The theories of origin, epidemiology and management are discussed with a literature review. CASE PRESENTATION: A 65 year old woman presented with a large thyroid swelling of 10 years duration and with swellings on the back and scalp which were diagnosed to be a follicular variant of papillary thyroid carcinoma with metastasis. Clinical examination, radiology and endoscopy ruled out any other abnormality of the upper aerodigestive tract. The patient was treated surgically with a total thyroidectomy with central compartment clearance and bilateral selective neck dissections. The histopathology revealed a collision tumor with components of both a follicular variant of papillary carcinoma and a squamous carcinoma. Immunohistochemical analysis confirmed the independent origin of these two primary tumors. Adjuvant radio iodine therapy directed toward the follicular derived component of the thyroid tumor and external beam radiotherapy for the squamous component was planned. CONCLUSION: Collision tumors of the thyroid gland pose a diagnostic as well as therapeutic challenge. Metastasis from distant organs and contiguous primary tumors should be excluded. The origins of squamous cancer in the thyroid gland must be established to support the true evolution of a collision tumor and to plan treatment. Treatment for collision tumors depends upon the combination of primary tumors involved and each component of the combination should be treated like an independent primary. The reporting of similar cases with longer follow-up will help define the epidemiology, biology and establish standardized protocols for treatment of these extremely rare tumors

Gradual distraction on hinged-based Ilizarov ring fixator to correct fixed flexion deformity of knee: description of the surgical technique

Knee deformity in flexion is the most disabling deformity. Surgical correction can be attempted with soft tissue release, osteotomy, or both. However, acute correction can cause serious complications. Ilizarov technique has become an appealing alternative to open surgery, where skeletal traction is used to distract the joint gradually and steadily in order to reduce the risk of skin problems or neurovascular injuries. Two patients and three limbs, male aged 28-42 (mean=35 years) with severe fixed flexion deformity were corrected by a hinged-based Ilizarov ring fixator. Mean flexion of the knee was pre-operatively 86.66 degrees (80-90 degrees). The mean extension angle at the last follow-up was 168.3 degrees (165-170). The mean knee society score (KSS) was 44.3 (35-50), mean KSS functional score was 43.3 (0-65). One patient had satisfactory outcomes and could stand without walking aids and walks on extended knee with walking aids. Arthrodesis of knee or creating a stiff knee in the most extended position may be most effective for severe, fixed contractures.With the gradual, calculated distraction, the Ilizarov apparatus is an effective tool for treating severe cases of knee contracture

Effect of telmisartan on sub-acute model of inflammation in male Wistar rats - an experimental study

Background: Cardiovascular diseases remain the major cause of death and premature disability in developed societies.Current predictions estimate that by the year 2020 cardiovascular diseases, notably atherosclerosis and hypertension will become leading global causes of total disease burden. The objective of the study was to investigate the influence of telmisartan on sub-acute model of inflammation in adult male Wistar rats.Methods: After obtaining ethical clearance from Institutional Animal Ethics Committee, animals were allotted to the three groups i.e. control, aspirin and telmisartan (n=6 animals in each group). The effect of telmisartan on inflammation was studied using sub-acute (Cotton pellet granuloma and histopathologic examination of grass piths) models. Experiment was conducted according to the Committee for the purpose of Control and Supervision of Experiments on Animals (CPCSEA) guidelines. Analysis was done using one way ANOVA followed by post hoc tests of Dunnett’s and Bonferroni’s. P<0.05 was considered as statistically significant.Results: In the present study telmisartan showed significant anti-inflammatory activity in sub-acute models of inflammation.Conclusions: In view of role of inflammation in the pathogenesis of atherosclerosis and their complications, treatment by telmisartan can reduce complications by virtue of its anti-inflammatory activity, in addition to its antihypertensive effect. Also this study may help to open new avenues for therapeutic indications of telmisartan.