Enhanced synchronization in an array of spin torque nano oscillators in the presence of oscillating external magnetic field

We demonstrate that the synchronization of an array of electrically coupled spin torque nano-oscillators (STNO) modelled by Landau-Lifshitz-Gilbert-Slonczewski (LLGS) equation can be enhanced appreciably in the presence of a common external microwave magnetic field. The applied microwave magnetic field stabilizes and enhances the regions of synchronization in the parameter space of our analysis, where the oscillators are exhibiting synchronized oscillations thereby emitting improved microwave power. To characterize the synchronized oscillations we have calculated the locking range in the domain of external source frequency.Comment: Accepted for publication in Europhysics Letters (EPL

Effects of tranexamic acid in major orthopedic surgical procedures: a randomized comparative study

Background: Despite modern healthcare system, major surgeries always cause economical constraints. Complications due to blood loss, long hospital stay are most common in major surgical procedures. Tranexamic acid (TXA), a synthetic derivative of lysine is used instead of blood transfusion to control bleeding peri and post operatively. Hence this study was planned to assess the effects of tranexamic acid on various orthopedic surgical procedures, in terms of blood loss, duration of surgical procedure and hospital stay.Methods: Prospective randomized comparative study, among patients undergoing elective and emergency orthopedic surgery. Patients with multiple fractures, organ injury and CKD were excluded from this study. Patients were randomized to tranexamic acid (TXA) group and colloids, blood transfusion group based on computer generated random numbers. Thirty two patients were randomized to tranexamic acid group and thirty two in control group. Statistical analysis was done using SPSS V 20.Results: The mean age group was 38.41±11.4 and 36.83±13.5 in TXA group and control group respectively. The mean SD for blood loss in TXA group was 321.5±124.7 and control group 482.7±189.6, the difference was found to be highly statistically significant with p=0.0002. Likewise the difference in postoperative Hb was found to be statistically significant with p<0.01. The p value for surgical site infection and hematoma was not statistically significant.Conclusions: TXA significantly reduces blood loss and blood transfusion requirements in patients undergoing orthopedic surgery

Effects of intra articular steroids, hyaluronic acid and combination of both among patients with knee osteoarthritis

Background: Osteoarthritis (OA) is a common degenerative disorder of articular cartilage accompanied by hypertrophic changes of the bone. In the management of OA, though use of intra articular (IA) injection of steroids, hyaluronic acid (HA) separately plays an important role, their effects in terms of reducing pain, joint stiffness and movement restriction when it is used in combination remains a question. Hence this study was planned to assess the effects of HA and steroids alone with combination of both Ha and steroids.Methods: Prospective randomized comparative study, among patients with osteoarthritis knee attending the outpatient department of Orthopedics in a tertiary care hospital during January 2017 to May 2018, were included. Patients were randomized in three groups (steroids, HA and combination of both) and a total of 96 patients were included and the outcome was assessed by WOMAC scale. Statistical analysis was done using SPSS Version 20.Results: Pain and movement restriction, at the end of fourth week and pain, joint stiffness and movement restriction, were found to be statistically improved in combined steroids and HA group than the group with steroids alone. Similarly at the end of third month, pain and movement restriction were found to be statistically improved in combined steroids and HA group than HA group alone.Conclusions: This study demonstrates that HA together with corticosteroid provides pain relief, reduction of joint stiffness and helps in improving joint movements within three months after treatment

An analysis of functional outcome following conservative versus surgical management in fractures of the distal radius

Background: Distal radial fractures are one of the most common injuries seen in the orthopaedic department, which can be managed both conservatively and surgically. There are advantages and disadvantages in each method of management. The aim of this study was to compare the functional and radiological outcomes of intra-articular fractures of the distal end of the radius with conservative and surgical management.Methods: 80 cases of intra articular fractures of the distal radius managed by both conservative and surgical means were studied between January 2011 to January 2013 and were followed up for a minimum period of two years.Results: In our series of 80 patients, there 53 males and 27 females. Most of the patients were between 20-30 years of age with the mean age being 40.35 years. RTA was the most common mode of injury (45%). Frykman’s type 3 (41.7%) was the most common fracture type seen followed by type 8. All fractures united by the end of 6 months. Excellent results were seen in 47.5% of cases in the surgical group and 30% of cases in the conservative group. Conclusions: From this study, we conclude that surgical management is better than conservative in the treatment of intra articular fractures of the distal end of radius. Therefore, one treatment method of treatment cannot be generalized for all types of fractures and treatment should be individualized to a particular fracture in terms of age, fracture pattern, degree of displacement and amount of communition present.

Transcriptional Control of Impaired Th1 Responses in Patent Lymphatic Filariasis by T-Box Expressed in T Cells and Suppressor of Cytokine Signaling Genes

T-bet (T-box expressed in T cells) and GATA-3 are transcription factors that play a critical role in the development of Th1 and Th2 cells, as do genes of the SOCS (suppressor of cytokine signaling) family, albeit indirectly. Another transcription factor, Foxp3, is a master regulator of natural regulatory T cells (Tregs). To identify the role of these factors in impaired Th1 responses of patent filarial infection, analysis of cytokine, SOCS, and transcription factor mRNA expression was performed on purified T cells of filaria-infected individuals (n � 6) and uninfected controls (n � 6). As expected (and in contrast to cells of uninfected individuals), there was a significant depression of gamma interferon (IFN-�) and a concomitant increase in interleukin-4 (IL-4), IL-5, and IL-10 mRNA expression following stimulation with parasite antigen (BmA) but not with a polyclonal T-cell (anti-CD3) stimulus. T-bet (but not GATA-3) was expressed at significantly lower levels in cells of filaria-infected individuals in response to BmA compared with those from the uninfected group, accounting, at least partially, for the diminished IFN-� expression. Second, we found no significant differences in expression of Foxp3 between the two groups, although induction of Foxp3 expression correlated with induced expression levels of IL-10, implicating Tregs in the IL-10 expression seen. Finally, parasitespecific T-cell expression of SOCS-1, SOCS-5, and SOCS-7 was significantly diminished among infected patients; in contrast, expression of SOCS-3 increased. Our data therefore indicate that the impaired Th1 responses observed in patent lymphatic filariasis are associated with decreased expression of T-bet, SOCS-1, SOCS-5, and SOCS-7 and increased expression of SOCS-3 in T cells

Synchronization of an array of spin torque nano oscillators in periodic applied external magnetic field

Considering an array of spin torque transfer nano oscillators (STNOs), we have investigated the synchronization property of the system under the action of a common periodically driven applied external magnetic field by numerically analyzing the underlying system of Landau-Lifshitz-Gilbert-Slonczewski (LLGS) equations for the macro-spin variables. We find the novel result that the applied external magnetic field can act as a medium to induce synchronization of periodic oscillations, both in-phase and anti-phase, even without coupling through spin current, thereby leading to the exciting possibility of enhancement of microwave power in a straightforward way.Comment: 6 pages, 8 figures, accepted for publication in Europhysics Letter

Factors Affecting the Productivity of Coffee in Gulmi and Arghakhanchi Districts of Nepal

Coffee is one of the major potential cash crops with lucrative export value grown in mid-hills of Nepal. Nepalese coffee production has suffered long by low productivity. Research was conducted from February to May, 2019 to analyze the factors affecting the productivity of coffee in Arghakhanchi and Gulmi districts of Nepal. These two districts were, purposively selected for this study taking account of comparative advantage and past studies recommendations for coffee sector. Altogether, 100 coffee growing households 50 from each, Arghakhanchi and Gulmi, were sampled by using multistage sampling technique. A pre-tested semi-structured interview schedule was used to collect the primary information while secondary information was collected reviewing the relevant publications. Ordinary Least Square (OLS) regression model was used to determine the factors affecting the productivity of coffee. The study revealed that the number of active family members involved in coffee production (0.000), adoption of income diversification through intercropping (0.005), training (0.072) and technical assistance (0.021) had positive and significant effect on coffee productivity. Encouraging the household to have coffee production as their primary occupation, providing technical assistance on rational land utilization and intercropping and strengthening the skill and knowledge of farmers through trainings could significantly support in increasing the productivity of coffee