Electrochemical Soft Actuator: Deciphering the Difference in the Characteristics of Polaronic and Bipolaronic Forms of Polyaniline.

Polyaniline (PANI) has been projected as an efficient electrochemical actuator due to its ease of synthesis, lightweight, biocompatibility, low cost, and possible low operating potential and high stress generation. However, challenges such as low inherent ionic and electronic conductivity of the polymer lead to small accumulation of ions and high ionic diffusion path length inside the polymer remain. In the present study, a highly conjugated, planar, conducting polaronic form of PANI with a nanofiber morphology is synthesized using in situ electrochemical polymerization on a reduced graphene oxide (rGO) electrode. The polymerization is carried out in the Schaefer mode at the air-water interface under controlled surface pressure in a Langmuir trough. Electrochemical, UV-visible, XPS, and Raman spectroscopic studies confirm the formation of the planar polaronic PANI form. Polymerization without surface pressure leads to the bipolaronic form of PANI. The two forms are subsequently used to understand their contributions toward electrochemical actuation in a bilayer configuration. The conducting polaronic PANI/EGO (exfoliated graphene oxide) exhibits a remarkably larger total angular displacement of 220° in aqueous 1 M NaClO4 during a potential scan in the range ±0.9 V than the bipolaronic counterpart which exhibits a total angular displacement of 125°. Current imaging in the scanning electrochemical microscopy mode confirms a high volumetric expansion in the case of the polaronic form as compared to its bipolaronic counterpart. Raman spectroscopy reveals the oxidation to the emeraldine form in the polaronic PANI and to the pernigraniline form in the bipolaronic form during actuation. Electrochemical impedance spectroscopy study evidences the existence of a small charge transfer resistance with high bulk capacitance for the polaronic structure.

Prospective evaluation of the diagnostic potential of LipL32 based latex agglutination test for Bovine leptospirosis

@#The Livestock Sector of India plays an important role in livelihood security and socioeconomic development of rural households. Leptospirosis is an important zoonotic disease responsible for septicaemia, interstitial nephritis, jaundice, abortion, reproductive problem in most of the animal species. Reproductive disturbances in bovine population is most often restricted to investigation of brucellosis, however apart from brucellosis, there are many undiagnosed diseases like leptospirosis that takes a toll in the reproductive anomalies of cattle and buffalo. Hence, the present study was elucidated to screen the seroprevalence of Leptospira in cattle and buffalo in various hamlets of North India using a user friendly screening test i.e. LipL32 latex agglutination test. The overall seropositivity was found to be 26.01% (230/884) in case of bovine in this study and the LipL32 LAT showed a profound sensitivity and specificity with level of 94.97% and 99.53% respectively.

A comparison of rescue and primary percutaneous coronary interventions for acute ST elevation myocardial infarction.

OBJECTIVE: To perform a comparative analysis of in-hospital results obtained from patients with acute ST elevation myocardial infarction (STEMI), who underwent rescue or primary percutaneous coronary intervention (PCI). The aim is to determine rescue PCI as a practical option for patients with no immediate access to primary PCI. METHODS: From the Cardiology PCI Clinic of the National Hospital of Sri Lanka (NHSL), we selected all consecutive patients presenting with acute STEMI

Outcome of early coronary intervention for acute ST elevation myocardial infarction in a tertiary care cardiac centre in Sri Lanka.

OBJECTIVES: To describe the outcomes of early percutaneous coronary intervention (PCI) for the treatment of acute ST elevation myocardial infarction (STEMI) in a tertiary care cardiac centre in Colombo, Sri Lanka. METHODS: Medical records of 139 consecutive patients presenting to Cardiology Unit 5, National Hospital of Sri Lanka from March 2013 to June 2014 with acute STEMI, and treated with early PCI as a mode of reperfusion were reviewed. These patients were then followed up for 6 months to determine survival, target-vessel revascularization, in-stent thrombosis and other major adverse cardiac events (MACE). RESULTS: Of 139 patients, 116 (83.5%) were male. Mean age was 52.3±SD11.1 years. Eighty eight (63.3%) patients underwent primary PCI and 51 (36.7%) underwent rescue PCI. There were six deaths (4.3%). One occurred on-table and three occurred after discharge. Four patients who died had cardiogenic shock. Mean door-to-balloon (DTB) time was 147 minutes for the primary PCI patients who were transferred from ETU. At six months, of 106 patients who attended follow up, two had been re-hospitalised for heart failure but none underwent coronary artery bypass grafting (CABG). CONCLUSIONS: This report from the national tertiary care cardiology referral centre in Sri Lanka, found that the study population was relatively younger, similar to other Asian countries. There was high rate of initial success (98.6%) and good short-term survival (95.7%), particularly in the subset presenting without cardiogenic shock (98.4%) despite the long DTB time. Loss to follow up at 6 months in this centre was 23.7% (33 patients).

Clinical evaluation of post-operative analgesia comparing suprascapular nerve block and interscalene brachial plexus block in patients undergoing shoulder arthroscopic surgery.

BACKGROUND: Shoulder arthroscopic surgeries have a high incidence of severe post-operative pain significant enough to interfere with recovery and rehabilitation. A regional anaesthetic technique combined with general anaesthesia reduces intra-operative requirements of anaesthesia and provides a better post-operative pain relief. As the commonly employed technique of interscalene brachial plexus block (ISB) is associated with potential serious complications, suprascapular nerve block (SSB) can be used as a safer alternative. METHODS AND MATERIAL: In this prospective study, 60 ASA 1 or 2 adult patients undergoing shoulder arthroscopic surgery were randomised into two groups - ISB and SSB. In group ISB, ISB with 20 ml of 0.5% bupivacaine mixed with 75 µg clonidine was given. In the SSB group SSB was given with 15 ml of 0.5% bupivacaine with 75 µg clonidine. Pain was assessed using visual analogue scale and verbal pain scale scores and time to first rescue analgesia was noted. We used Student's t test and Chi-square/Fisher Exact test and used a statistical software to compare data. RESULTS: In the present study, the mean duration of analgesia was 2.53 ± 2.26 h in SSB group compared to 7.23 ± 6.83 h in group ISB (p value < 0.05). Overall rescue analgesic requirements were higher in SSB group compared to ISB group (63.3% versus 40.0%) but this was statistically not significant (p value > 0.05). CONCLUSION: Both interscalene and SSB can be used to provide intra-operative and post-operative analgesia in patients undergoing shoulder arthroscopy.

Medical physics aspects of cancer care in the Asia Pacific region: 2011 survey results.

BACKGROUND: Medical physicists are essential members of the radiation oncology team. Given the increasing complexity of radiotherapy delivery, it is important to ensure adequate training and staffing. The aim of the present study was to update a similar survey from 2008 and assess the situation of medical physicists in the large and diverse Asia Pacific region. METHODS: Between March and July 2011, a survey on profession and practice of radiation oncology medical physicists (ROMPs) in the Asia Pacific region was performed. The survey was sent to senior physicists in 22 countries. Replies were received from countries that collectively represent more than half of the world's population. The survey questions explored five areas: education, staffing, work patterns including research and teaching, resources available, and job satisfaction. RESULTS AND DISCUSSION: Compared to a data from a similar survey conducted three years ago, the number of medical physicists in participating countries increased by 29% on average. This increase is similar to the increase in the number of linear accelerators, showing that previously identified staff shortages have yet to be substantially addressed. This is also highlighted by the fact that most ROMPs are expected to work overtime often and without adequate compensation. While job satisfaction has stayed similar compared to the previous survey, expectations for education and training have increased somewhat. This is in line with a trend towards certification of ROMPs. CONCLUSION: As organisations such as the International Labour Organization (ILO) start to recognise medical physics as a profession, it is evident that despite some encouraging signs there is still a lot of work required towards establishing an adequately trained and resourced medical physics workforce in the Asia Pacific region.

Graphene and graphene oxide as effective adsorbents toward anionic and cationic dyes.

In the present study, exfoliated graphene oxide (EGO) and reduced graphene oxide (rGO) have been used for the adsorption of various charged dyes such as methylene blue, methyl violet, rhodamine B, and orange G from aqueous solutions. EGO consists of single layer of graphite decorated with oxygen containing functional groups such as carboxyl, epoxy, ketone, and hydroxyl groups in its basal and edge planes. Consequently, the large negative charge density available in aqueous solutions helps in the effective adsorption of cationic dyes on EGO while the adsorption is negligible for anionic dyes. On the other hand, rGO that has high surface area does not possess as high a negative charge and is found to be very good adsorbent for anionic dyes. The adsorption process is followed using UV-Visible spectroscopy, while the material before and after adsorption has been characterized using physicochemical and spectroscopic techniques. Various isotherms have been used to fit the data, and kinetic parameters were evaluated. Raman and FT-IR spectroscopic data yield information on the interactions of dyes with the adsorbent.

Medical physics aspects of cancer care in the Asia Pacific region.

Medical physics plays an essential role in modern medicine. This is particularly evident in cancer care where medical physicists are involved in radiotherapy treatment planning and quality assurance as well as in imaging and radiation protection. Due to the large variety of tasks and interests, medical physics is often subdivided into specialties such as radiology, nuclear medicine and radiation oncology medical physics. However, even within their specialty, the role of radiation oncology medical physicists (ROMPs) is diverse and varies between different societies. Therefore, a questionnaire was sent to leading medical physicists in most countries/areas in the Asia/Pacific region to determine the education, role and status of medical physicists.Answers were received from 17 countries/areas representing nearly 2800 radiation oncology medical physicists. There was general agreement that medical physicists should have both academic (typically at MSc level) and clinical (typically at least 2 years) training. ROMPs spent most of their time working in radiotherapy treatment planning (average 17 hours per week); however radiation protection and engineering tasks were also common. Typically, only physicists in large centres are involved in research and teaching. Most respondents thought that the workload of physicists was high, with more than 500 patients per year per physicist, less than one ROMP per two oncologists being the norm, and on average, one megavoltage treatment unit per medical physicist.There was also a clear indication of increased complexity of technology in the region with many countries/areas reporting to have installed helical tomotherapy, IMRT (Intensity Modulated Radiation Therapy), IGRT (Image Guided Radiation Therapy), Gamma-knife and Cyber-knife units. This and the continued workload from brachytherapy will require growing expertise and numbers in the medical physics workforce. Addressing these needs will be an important challenge for the future.