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There is an urgent need to have reliable technologies to diagnose post-coronavirus disease syndrome (PCS), as the number of people affected by COVID-19 and related complications is increasing worldwide. Considering the amount of risks associated with the two chronic lung diseases, asthma and chronic obstructive pulmonary disease (COPD), there is an immediate requirement for a screening method for PCS, which also produce symptoms similar to these conditions, especially since very often, many COVID-19 cases remain undetected because a good share of such patients is asymptomatic. Breath analysis techniques are getting attention since they are highly non-invasive methods for disease diagnosis, can be implemented easily for point-of-care applications even in primary health care centres. Electronic (E-) nose technology is coming up with better reliability, ease of operation, and affordability to all, and it can generate signatures of volatile organic compounds (VOCs) in exhaled breath as markers of diseases. The present report is an outcome of a pilot study using an E-nose device on breath samples of cohorts of PCS, asthma, and normal (control) subjects. Match/no-match and k-NN analysis tests have been carried out to confirm the diagnosis of PCS. The prediction model has given 100% sensitivity and specificity. Receiver operating characteristics (ROC) has been plotted for the prediction model, and the area under the curve (AUC) is obtained as 1. The E-nose technique is found to be working well for PCS diagnosis. Our study suggests that the breath analysis using E-nose can be used as a point-of-care diagnosis of PCS.Trial registrationBreath samples were collected from the Kasturba Hospital, Manipal. Ethical clearance was obtained from the Institutional Ethics Committee, Kasturba Medical College, Manipal (IEC 60/2021, 13/01/2021) and Indian Council of Medical Research (ICMR) (CTRI/2021/02/031357, 06/02/2021) Government of India; trials were prospectively registered. Graphical abstract

Background Idiopathic pulmonary fibrosis (IPF) is one of the common types of interstitial lung disease having high prevalence and mortality worldwide. As a result of patient-centred hindering factors of adherence to centre-based pulmonary rehabilitation (PR), home-based PR is an alternate mode of rehabilitating individuals with IPF. This systematic review will evaluate the effectiveness of unsupervised home-based PR on functional capacity and health-related quality of life (HRQoL) in individuals with IPF. Methods Clinically stable, high resolution computed tomography and physician diagnosed IPF participants having modified Medical Research Council score below 5 will be considered for the systematic review. Studies involving home-based PR as an intervention to treat individuals with IPF will be considered. Randomised controlled trials and quasi-randomised studies (with two groups followed up) are eligible to be included. Outcomes of our interest are functional capacity (6-min walk distance, shuttle walk test and incremental shuttle walk test) and secondary outcome measure would include assessment of quality of life and adverse effects of intervention. Electronic databases such as SCOPUS, Medline (PubMed and Web of Science), PEDRo and CINAHL will be searched using database specific terms. Additionally, forward and backward citations of included studies will be searched to identify potential records. Two review authors, independently, will conduct the screening, data extraction using a customised standard tool, and critical appraisal using Cochrane Risk of Bias 2 tool of included studies. If data permits, meta-analysis will be conducted. In case of substantial heterogeneity, we will do a narrative synthesis. Subgroup analysis will be undertaken based on various contextual and interventional factors. Discussion This review will provide comprehensive evidence on the effectiveness of unsupervised home-based PR to physiotherapists, policy makers and researchers who are interested in IPF management. Findings from this review may guide the development and evaluation of more robust evidence based home-based PR that aimed to improve functional capacity among people with IPF. Systematic review registration PROSPERO CRD42020213883.

Introduction: The unprecedented outbreaks of corona virus disease of 2019 (COVID-19) have highlighted the necessity of readily available, reliable, precise, and faster techniques for its detection. Nasopharyngeal swab has been the gold standard for the diagnosis of COVID-19. However, it is not an ideal screening procedure for massive screening as it implicates the patient's stay in the hospital or at home until diagnosis, thus causing crowding of the specimen at the diagnostic centers. Present study deal with the exploration of potential application of different body fluids using certain highly objective techniques (Optical and e-Nose) for faster detection of molecular markers thereby diagnosing viral infections.Areas covered: This report presents an evaluation of different body fluids, and their advantages for the rapid detection of COVID-19, coupled with highly sensitive optical techniques for the detection of molecular biomarkers.Expert opinion: Tears, saliva, and breath samples can provide valuable information about viral infections. Our brief review strongly recommends the application of saliva/tears and exhaled breath as clinical samples using technics such as high-performance liquid chromatography-laser-induced fluorescence, photoacoustic spectroscopy, and e-Nose, respectively, for the fast diagnosis of viral infections.

Exhaled breath contains small molecules and complex volatile organic compounds (VOCs) such as H2O, CO2, NO, NH3, ketones, aldehydes, alcohols, and hydrocarbons. Analysis of VOCs can provide valuabl...

Centre-based pulmonary rehabilitation is an effective, non-pharmacological intervention in improving outcomes for people with interstitial lung disease (ILD). Home-based pulmonary rehabilitation (PR) is a lower-cost rehabilitation alternative for people with chronic respiratory diseases. The aims of this study are to evaluate the efficacy of home-based PR on functional capacity and health-related quality of life in people with ILD, as well as to assess changes in dyspnea and fatigue, muscle strength, activities of daily living, depression, and anxiety after completing a home-based PR program.Ninety-six individuals with ILD will be randomly assigned to either an intervention group (home-based PR exercise training program) or a control group (usual care). An assessor blind to group allocation will measure the 6-min walk distance, peripheral muscular strength, health-related quality of life, dyspnoea, anxiety and depression, fatigue, activities of daily living, upper limb and lower limb endurance at baseline, at program completion one month, and three months after the intervention.If home-based PR programs are proven to be beneficial over time, they will address a critical gap by giving a readily accessible and viable choice of rehabilitation to people with ILD, enabling more people to participate in an exercise program.

A 71-year-old male presented with progressive exertional breathlessness and cough for the last four years. His breathlessness aggravated after a heavy meal and on lying down. He was a smoker, but had no co-morbidities. He did not remember any major trauma or surgery. Examination of the respiratory system revealed mediastinal shift to the left, diminished breath sounds over the whole of the right hemithorax and gurgling sounds all over, mainly the infrascapular area. Examination of other organ systems revealed no abnormality.

Economic, social and psychological distress is common in individuals affected by tuberculosis (TB). However, the magnitude of distress, psychological interventions and their effect on the treatment outcomes are often under-evaluated. We examined the level of psychological stress and health-related quality of life (HRQoL) of such patients and the effect of antituberculosis therapy on them. Our prospective cohort study included newly diagnosed adult pulmonary and extrapulmonary TB patients. Assessment of psychological stress was done using the seven-item Generalised Anxiety Disorder questionnaire for anxiety and the nine-item Patient Health Questionnaire for depression. HRQoL was assessed by using the WHOQOL-BREF questionnaire. Of the 86 patients studied, 21 (24.4%) had anxiety symptoms at the baseline, which reduced to 5.8% and 1.2% at 2 months and treatment completion, respectively (p, Tuberculosis patients experience significant psychological stress that can negatively impact their quality of life and warrants proper screening and intervention. https://bit.ly/3jfMEjA

Coronavirus disease–2019 (COVID-19), caused by severe acute respiratory syndrome–coronavirus disease-2, is the first pandemic that has been caused by a coronavirus The COVID-19 pandemic has already led to a marked increase in burdens including disease, disability, and health-care system costs Patients with COVID-19 may present with a broad spectrum of clinical features such as fever, cough, shortness of breath, myalgia, fatigue, sore throat, hemoptysis, and diarrhea To our knowledge, no specific antiviral or vaccine is available for COVID-19 treatment and prevention Present-day management includes supportive care, oxygen supplementation, and mechanical ventilatory support when indicated, along with infection control measures Apart from physical symptoms, patients usually face various so-cial or psychological problems;hence, comprehensive health status assessment is essential During the first year following acute respiratory distress syndrome of any cause, more than two-thirds of survivors reported clinically significant fatigue symptoms This proves the need for appropriate rehabilitation for COVID-19 survivors Pulmonary rehabilitation aims to improve respiratory function and quality of life in patients with various disorders Studies are re-quired to define those patients with impaired health conditions after COVID-19 infection during follow-up However, an easy method for prescribing pulmonary rehabilitation is according to disease severity Rehabilitation must start at admission and continue after discharge At the time of discharge from a COVID care center, patients must be educated for home-based rehabilitation © 2020 by Begell House, Inc

Reaction time is one of the components of functional balance and could contribute to balance impairment. Information regarding this relationship is scant among Chronic Obstructive Pulmonary Disease (COPD) participants.To compare stepping reaction time between participants with COPD and age; gender-matched healthy individuals to find out whether reaction time in COPD population is affected.This cross-sectional study included 41 COPD participants and 41 age and gender-matched healthy individuals. All the participants underwent measurements of stepping reaction time (SRT) and timed up and go test (TUG).SRT was significantly higher in COPD participants compared to healthy individuals [median of difference- 350 milliseconds (110, 830), p0.001]. TUG was significantly higher in COPD participants compared to healthy individuals [median of difference = 2.82 seconds (0.34 and 4.5), p0.001].Participants with COPD exhibit marked increase in SRT and demonstrate a deficiency in functional balance compared to the healthy participants.

Objectives: The objective of this study was to assess the effects of home-based exercise training (HBET) on function and quality of life (QoL) in patients with pulmonary hypertension (PH). Methods: A prospective, nonblinded, randomized clinical trial was carried out on 84 medically stable patients with PH belonging to any functional class or etiology and of either sex. Patients were randomized to either standard care or HBET. Both groups also received education using the Pulmonary Hypertension Manual (PulHMan). Outcomes included functional capacity from 6-min walk distance (6MWD), QoL using the Medical Outcomes Survey Short Form – 36, functional class (FC), and right heart indices (right ventricular systolic pressure [RVSP] and tricuspid annular plane systolic excursion [TAPSE]) and were assessed at entry and after 12 weeks. Results: HBET improved 6MWD by 48.5 m and 13 m in the experimental and control groups, respectively (p

Photoacoustic spectroscopy is a well-known spectroscopic method for gas detection. Exhaled breath contains volatile organic compounds (VOCs) as bio-markers of specific health condition. Detection and quantification of VOC bio-markers from exhaled breath can provide valuable information about the health status. We report the design and development of Photoacoustic spectroscopy setup and a preliminary study of the detection of certain standard VOCs.

Context: Fractional exhaled nitric oxide (FeNO) is a noninvasive test for airway inflammation in asthma. The usefulness of FeNO in predicting exacerbations is uncertain. Aims: The study aims to assess and compare the ability of FeNO, spirometry, and asthma control test (ACT) in predicting future exacerbations of asthma and their correlation with each other. Settings and Design: This prospective, cohort study was conducted at the Department of Respiratory Medicine, Kasturba Medical College, Manipal. Materials and Methods: Adult asthma patients of age 18–65 years were included. Patients with a smoking history of >10 pack-years and those in whom spirometry was contraindicated were excluded. Patients who consented underwent FeNO and spirometry. The control of asthma was assessed using the ACT questionnaire. We captured the number of exacerbations in the follow-up period of 4 months. Statistical Analysis Used: Mann–Whitney test was used to compare the utility of FeNO, spirometry, ACT in predicting exacerbations and Spearman's correlation coefficient was used to ascertain the correlation among them. Results: Of 154 study patients, 28% had exacerbations. We found that there was no significant difference in FeNO in patients with and without exacerbations. The median (interquartile range [IQR]) FEV1% in the patients with and without exacerbations were 68 (55–79) and 75 (65–88), respectively (P = 0.013). The median (IQR) ACT score in patients with exacerbations was 12 (10–16) which was significantly lower than in those without exacerbation in whom it was 16 (14–18) (P = 0.003). There was a negative correlation of ACT with FeNO (Correlation coefficient: −0.167, P = 0.038). The median (IQR) FeNO level (ppb) was lower in patients who were on inhaled corticosteroid (ICS) than in the other group values being 22 (14–38) and 30 (17–58), respectively (P = 0.05). Conclusions: In our study, FEV1% and ACT score could predict exacerbations of asthma whereas FeNO could not. FeNO level correlated inversely with ACT score. FeNO level decreased with inhaled corticosteroid usage.

Context: Magnesium (Mg) is an intracellular cation which takes part in various functions including smooth muscle contractility. Studies have shown that serum Mg level has no significant effect on asthma severity. There are only sparse data on the effect of serum Mg level on asthma control. Aims: The aim of this study was to evaluate the effect of serum Mg level on asthma control. Settings and Design: This hospital-based cross-sectional study was conducted at the Department of Respiratory Medicine, Kasturba Medical College, Manipal. Subjects and Methods: Our participants were adult asthma patients over 18 years of age. Asthma control was assessed using a questionnaire. Serum Mg level was estimated. The study was approved by the Institutional Ethics Committee, and informed consent was obtained from the participants. Statistical Analysis Used: Welch's ANOVA test was used to analyze the correlation between serum Mg level and level of control of asthma. Results: We screened 256 patients who met the inclusion criteria. After 96 patients were removed based on exclusion criteria, 160 patients were grouped into three based on the level of symptom control. Forty-eight patients belonged to the “well controlled” group, 59 in “partly controlled” group, and the remaining 53 in “uncontrolled” group. The mean serum Mg level (mg/dl) was 2.08 ± 0.37, 2.07 ± 0.28, and 1.83 ± 0.34 in well, partly, and uncontrolled groups, respectively. As the level of control of asthma decreased from well controlled to uncontrolled, the level of mean serum Mg also decreased. Conclusions: Serum Mg levels have a positive correlation with the level of symptom control in asthma. In uncontrolled asthma, serum Mg is significantly low. Hence, it might be useful as a biomarker in assessing control or severity of asthma.

Ethnopharmacological relevance Paederia foetida Linn. (Family: Rubiaceae) is widely used as a natural remedy for diabetes mellitus by the Nepali and Lepcha tribes of Sikkim and Darjeeling Himalayan region. The plant is administered to a diabetic individual in the form of leaf infusion for 2–3 weeks. Therefore, we investigated the effects of methanolic leaf extract of Paederia foetida (MEPF) on alloxan (ALX) induced diabetic renal oxidative stress and NF-kB dependent renoinflammatory events in rat. Method Effects of MEPF on blood glucose, glomerular filtration rate (GFR), serum and oxidative stress markers were evaluated in ALX induced diabetic wistar rats. Enzyme linked immunosorbent assay (ELISA) was carried out to estimate serum IL-6, IL-1β, TNF-α and renal tissue NF-kB p65 levels. MEPF treatment was given to the diabetic rats at a dose of 250 and 500 mg/kg body weight (b.w.). Results & discussion MEPF treatment significantly reduced hyperglycaemia, serum creatinine, blood urea nitrogen (BUN), bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglycerides (TRIGs), and total cholesterol (TCHOL) levels in the diabetic rats, whereas it significantly restored GFR and serum albumin level. The activity of enzymatic and non-enzymatic antioxidant machineries was remarkably augmented by MEPF treatment. Likewise, it also significantly lowered lipid peroxidation which was evidenced by decreased concentration of thiobarbituric reactive substances (malondialdehyde, MDA) in the renal tissue of treated diabetic groups. Moreover, MEPF treated animals exhibited low serum concentrations of IL-6, IL-1β and TNF-α compared to the diabetic control rats. It showed a dose dependent inhibition of NF-kB activation in the diabetic kidney, but the effects were more prominent at a dose of 500 mg/kg. Histopathological examinations also confirmed its nephroprotective action during diabetes. Conclusion MEPF treatment mitigates oxidative stress and suppresses renal inflammation via inhibition of NF-kB in diabetic kidney in early progressive diabetic nephropathy.

BODE index is a multidimensional measure of survival in chronic obstructive pulmonary disease (COPD). It is composed of body mass index (B), the degree of airflow obstruction (O), dyspnoea (D), and exercise capacity (E). Studies have shown that BODE index can predict future exacerbations, but similar data in Indian population is unavailable. This study was aimed at evaluating the power of BODE index to predict the frequency of exacerbations of COPD in Indian cohort.We conducted a prospective observational cohort study that included stable COPD subjects aged above 40 years. We assessed the BODE index at baseline and recorded the number of exacerbations at the end of 12 months. Spearman's Rho and Poisson regression model were used to correlate the BODE index with the frequency of exacerbations.We analysed 78 COPD patients. A significant correlation was seen between BODE index at baseline and number of exacerbations at 12 months (Spearman's Rho 0.738). A unit change in BODE index at baseline would have 1.25 times higher number of exacerbations at 12 months (95% CI: 1.17-1.33).BODE index has significant power to predict the frequency of future exacerbations in Indian COPD patients.

Obstructive sleep apnea (OSA) is one of the systemic risk factors for glaucoma which causes irreversible visual field (VF) damage. We reviewed the published data of all types of studies on the association between these two conditions and papers regarding functional and structural changes related to glaucomatous damage using Scopus, web of science, and PubMed databases. There is evidence that the prevalence of glaucoma is higher in OSA patients, which independent of intraocular pressure (IOP). Studies have reported thinning of retinal nerve fiber layer (RNFL), alteration of optic nerve head, choroidal and macular thickness, and reduced VF sensitivity in patients of OSA with no history glaucoma. A negative correlation of apnea-hypopnea index with RNFL and VF indices has been described in some studies. Raised IOP was noted which is possibly related to obesity, supine position during sleep, and raised intracranial pressure. Diurnal fluctuations of IOP show more variations in OSA patients before and after continuous positive airway pressure (CPAP) therapy when compared with the normal cases. The vascular factors behind the pathogenesis include recurrent hypoxia with increased vascular resistance, oxidative stress damage to the optic nerve. In conclusion, comprehensive glaucoma evaluation should be recommended in patients with OSA and should also periodically monitor IOP during CPAP treatment which may trigger the progression of glaucomatous damage.

The present cross-sectional study was conducted for the first time from the Udupi district of coastal Karnataka to know the prevalence of drug resistance and comparative analysis of MDR and non-MDR cases of pulmonary tuberculosis. Details of 862 smear positive cases of pulmonary tuberculosis with age ⩾15years from 12 designated microscopy centres of the Udupi district were studied. Initially 2 sputum samples trailed by one follow-up sample were collected from each patient and processed for culture and drug sensitivity on the Lowenstein-Jensen medium. A total resistance of 33.4% was observed that includes the mono-resistance of 22.5%, multidrug resistance (MDR) of 6.3% and extensive drug resistance (XDR) of 0.3%. Significant odds ratio (OR) was observed in category 2 cases (OR 3.9) for the development of MDR tuberculosis. A significant statistical association was observed using Fisher’s exact test while comparing mortality rate (19.3% vs. 1.8%), treatment failure (8.8% vs. 3.8%) and cure rate (68.4% vs. 85.4%) between MDR and non-MDR cases (p

Introduction: Erectile Dysfunction (ED) is one of the distressing comorbidities associated with Chronic Obstructive Pulmonary Disease (COPD). There is a paucity of literature on the association of erectile function and marital quality in Indian COPD population. Aim: To find out whether Erectile Dysfunction (ED) affects the marital quality in COPD subjects. Materials and Methods: This cross-sectional study included 87 stable COPD patients, aged more than 40, who were married and staying with their partners. The patients were screened for psychiatric comorbidity using General Health Questionnaire- 28 (GHQ) and Hospital Anxiety and Depression Scale (HADS). Erectile dysfunction was assessed using International Index of Erectile Function (IIEF) questionnaire. The patients were grouped into those having and not having ED. ‘Marital quality’ and ‘relationship and sexuality’ scales were used to compare the groups. Results: Among the 87 study participants, 37 had ED while 50 were non-ED. The ‘Marital Quality’ and ‘Relationship and Sexuality’ scores were significantly lower in the non-ED group and ED group respectively (p-value ≤ 0.001). Age had no significant correlation to IIEF (0.164), ‘Marital Quality’ (0.14) and ‘Relationship and Sexuality’ (-0.094). There was a significant positive correlation between FEV1 values and ‘‘Relationship and Sexuality’ scores (0.228), but none to ‘Marital Quality’ (0.58) and IIEF (-0.204) scores. Conclusion: The study confirms that erectile function is a significant predictor of marital quality in COPD. The marital relationship and sexuality are found to be related to lung function.

Reactive arthritis (ReA) is commonly associated with gastroenteritis by Yersinia, Salmonella, Shigella, Campylobacter, and Clostridium difficile and genitourinary infections by Chlamydia trachomatis and Neisseria gonorrhea. Urinary tract infection (UTI) with Escherichia coli is rarely associated with ReA. Failure to screen for UTI, especially in patients with asymptomatic bacteriuria, can lead to delayed diagnosis and inappropriate treatment. A 31-year-old homemaker, who had been diagnosed with pulmonary TB 1 month back and had completed 1 month of successful anti-TB therapy, presented with pain and swelling of the right knee and fever of 1-week duration. She had healing erythema nodosum on both her thighs. Her right knee had pain and swelling that lead to restriction of movements. X-ray of the right knee showed joint effusion with no joint destruction. Work up for autoimmune arthritis was negative. Synovial fluid studies ruled out septic arthritis, crystal arthropathies, and tuberculous arthritis. Urinalysis suggested UTI and urine culture isolated E. coli. Hence, we made the diagnosis of ReA due to UTI with E. coli. She received oral nonsteroidal anti-inflammatory drugs and a course of ciprofloxacin. She had a complete recovery.

Poly (lactic acid) (PLA) and poly (butylene adipate-co-terephthalate) (PBAT) blend nanocomposites were prepared using melt blending technique followed by compression moulding. The blend nanocomposites were prepared with a variation of PBAT loading along with maleic anhydride and benzoyl peroxide ranging from 5 to 20 wt% along with two different commercially available nanoclays cloisite 93A and cloisite 30B (C30B) at 3 wt% loading. The maleic anhydride and benzoyl peroxide were used during the melt blending of the blend nanocomposites as a compatibilizer and as an accelerator respectively. Maleic anhydride used to enhance the compatibility of the PLA/PBAT blend and as well as the uniform adhesion of the nanoclays with them. The properties and characterizations of PLA matrix and the PLA/PBAT blend nanocomposites have been studied. The tensile strength, % elongation and impact strength increased with the preparation of PLA/PBAT blend nanocomposites as compared with PLA matrix. PLA/PBAT/C30B blend nanocomposites exhibited optimum tensile strength at 15 wt% of PBAT loading. Differential scanning calorimetry and thermogravimetric analysis also showed improved thermal properties as compared with virgin PLA. The wide angle X-ray diffraction studies indicated an increase in d-spacing in PLA/PBAT/C30B blend nanocomposite thus revealing intercalated morphology.

A 40-year-old male, non-smoker, presented with cough and right-sided pleuritic chest pain of 10 days and fever of 1-day duration. His previous medical and surgical history was unremarkable. There was no history of significant illness in the family. General physical examination and vital signs were

Poly(ethylene glycol) (PEG) was mixed at various weight percentage with biodegradable poly(lactic acid) (PLA) via direct melt compounding method. Nanocomposites of PLA/PEG, with two types of organoclay namely, cloisite 93A (C93A) and cloisite 30B (C30B) were also prepared by melt blending method. The crystallization behaviors of PLA/PEG and PLA/PEG/organoclay were studied using differential scanning calorimetry (DSC). The isothermal crystallization kinetics has been investigated using the Avrami’s equation. In PLA/PEG, the PLA crystallized first followed by crystallization of PEG during the cooling. The viscoelastic behavior of the PLA/PEG and PLA/PEG/organoclay were investigated by dynamic mechanical analysis where the nanocomposites showed higher magnitude of storage modulus. The plasticizing effect of PEG acts predominantly in the mechanical performance of PLA/PEG, which shows increased percentage elongation and impact strength in the blend. The sample with 20 wt% PEG showed optimum impact strength. Again, the nanocomposite with 3 wt% C30B exhibited better tensile strength and modulus than the sample with C93A. The characterization of fractured surface of the matrix polymer and the blend were compared through scanning electron microscopy. The rheological and compostability study of the system were further investigated.

In this study, the effect of poly(ethylene glycol) (PEG) on the preparation of Poly(lactic acid) (PLA)/PEG blend and its nanocomposites by melt intercalation method were investigated. The PEG having molecular weight of 6,000 g/mol used with various concentrations (0, 10, 15, 20, 25, 30 wt%) in the preparation of PLA/PEG blend. Again, two types of commercialized organoclay [cloisite 93A (C93A) and cloisite 30B (C30B)] were used for the preparation of blend nanocomposites. With the incorporation of PEG into PLA the tensile strength and modulus decreases, whereas the percentage elongation and impact strength increases predominantly. Further, the PLA/PEG blend nanocomposites showed improved tensile strength and modulus with the addition of oraganoclays into the blend. Scanning electron microscopy (SEM) reveals the surface and miscibility study of the PLA/PEG blend. The effect of clay interaction in the PLA/PEG blend nanocomposites were also studied by using wide angle X-ray diffraction (WAXD) and transmission electron microscopy (TEM). Dynamic mechanical analysis (DMA) was used to investigate the viscoelastic behavior of the blends and its nanocomposites. Differential scanning calorimetry (DSC) study reveals decreased glass transition temperature in case of PLA/PEG blend. The thermal stability of the blend and its nanocomposites were being studied by using thermogravimetric analysis (TGA). POLYM. COMPOS., 35:283–293, 2014. © 2013 Society of Plastics Engineers

Polylactic acid (PLA) nanocomposites were prepared using melt blending technique. Two different commercially available nanoclays, Cloisite 93A (C93A) and Cloisite 30B (C30B) at various wt%, have been used to prepare the nanocomposites. The mechanical properties of the nanocomposites have been studied to evaluate the effect of the nanoclay within the matrix polymer. Mechanical tests revealed an increase in the mechanical properties with the incorporation of organically modified nanoclays as compared with PLA matrix. PLA/C30B nanocomposites exhibited optimum tensile modulus at 3 wt% of clay loading. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) studies were also performed to evaluate the thermal behavior of the nanocomposites. Further, viscoelastic behavior in the nanocomposites has been investigated using dynamic mechanical analysis (DMA) to study the damping behavior of the materials. Also the morphological study was carried out through X-ray diffraction analysis, and a better exfoliation or dispersion of C30B clay with PLA matrix was observed. The interaction between the clays and PLA matrix has also been studied using transmission electron microscopy (TEM).

Poly(lactic acid) (PLA) nanocomposites were prepared by melt mixing technique in a Haake batch mixer. The clay dispersion within the PLA matrix during melt mixing was well explained through the morphological characterization. Morphological characterizations were studied by X-ray diffraction and transmission electron microscopy. The exfoliation/intercalation of the clay particles within the polymer matrix during melt mixing depends on the mixing torque generated during the preparation of nanocomposites. The significance of processing temperature and the mixing time in melt mixing were studied for PLA/C93A and PLA/C30B nanocomposites. The structure and properties of the nanocomposites were also characterized by differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical analysis, and mechanical properties by standard tensile testing. The incorporation of nanoclays into the PLA matrix enhanced the mechanical properties and thermal stability of the PLA nanocomposites. This may be due to the reinforcing effect of nanoclays within the polymer matrix. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers

The mechanical properties of polylactic acid (PLA)/nanoclay were examined using the composite theories. Among Guth equation, Halpin-Tsai Equation and Modified Halpin-Tsai equation, the Halpin-Tsai equation is universally used for composites reinforced by fiber-like or rod-like fillers. A brief comparison made for the Young’s modulus of the platelet-like fillers between the theoretical and experimental data. The experimental procedure followed for the determination of the aspect ratio statistically through the analysis of transmission electron microscope (TEM). The modulus reduction factor (MRF) is more significant towards the improvement of predicted theoretical values of the modulus. By introducing the modulus reduction factor (MRF) the polymer-clay nanocomposites was better explained through the composite theory.

Background Pulmonary arterial hypertension (PAH) causes profound functional limitations and poor quality of life. Yet, there is only a limited literature available on the role of exercise training. This paper systematically reviews the effects of exercise training on exercise capacity in PAH. Methods A systematic search of databases (PubMed, CINAHL, CENTRAL, Web of Science and PEDRo) was undertaken for English language articles published between 1 st January 1980 and 31 st March 2015. Quality rating for all articles was done using the Downs and Black scoring system. Results Fifteen articles of good (n=4), moderate (n=6) and poor (n=5) quality were included in the review. Exercise interventions included aerobic, resistance, inspiratory muscle training or a combination, for 6-18 weeks. Improvements were seen in exercise capacity (six minute walk distance (6MWD) and peak VO2) by 17-96m and 1.1-2.1ml/Kg/min, functional class by one class and quality of life, with minimal adverse events. Conclusions There is evidence to recommend the use of exercise training as an adjunct to medical treatment in PAH. More clinical trials and research are required to assess the effects of different types of exercise programs in patients with PAH, while focussing on strong exercise endpoints to quantify the improvements seen with exercise training.