Improvement of isometric dorsiflexion protocol for assessment of tibialis anterior muscle

It is important to accurately estimate the electromyogram (EMG)/force relationship of triceps surae (TS) muscle for detecting strength deficit of tibalis anterior (TA) muscle. In literature, the protocol for recording EMG and force of dorsiflexion have been described, and the necessity for immobilizing the ankle has been explained. However, there is a significant variability of the results among researchers even though they report the fixation of the ankle. We have determined that toe extension can cause significant variation in the dorsiflexion force and EMG of TS and this can occur despite following the current guidelines which require immobilizing the ankle. The results also show that there was a large increase in the variability of the force and the RMS of EMG of TS when the toes were not strapped compared with when they were strapped. Thus, with the current guidelines, where there are no instructions regarding the necessity of strapping the toes, the EMG/force relationship of TS could be incorrect and give an inaccurate assessment of the dorsiflexor TA strength. In summary, - Current methodology to estimate the dorsiflexor TA strength with respect to the TS activity, emphasizing on ankle immobilization is insufficient to prevent large variability in the measurements. - Toe extension during dorsiflexion was found to be one source of variability in estimating the TA strength. - It is recommended that guidelines for recording force and EMG from TA and TS muscles should require the strapping of the toes along with the need for immobilizing the ankle

Differentiation of constrictive pericarditis and restrictive cardiomyopathy using digitized echocardiography

Constrictive pericarditis and restrictive cardiomyopathy are difficult to distinguish at the bedside and occasionally at routine cardiac catheterization. Left ventricular diastolic function was studied by computer analysis of digitized M-mode echocardiograms in four patients with constrictive disease and three with restrictive disease, and the data were compared with those of normal subjects. The respective distinguishing echographic features of constrictive pericarditis and restrictive cardiomyopathy were as follows: the major filling period of the left ventricle was 78 ± 9% of normal versus 128 ± 4% (p < 0.01), minimal left ventricular dimension to peak filling interval was 50 ± 10 versus 110 ms (p < 0.05) and the maximal rate of left ventricular posterior wall thinning was −4.9 versus −2.3 seconds−1(p < 0.05). This preliminary study suggests that it may be possible to accurately diagnose the two disease entities using this technique at the bedside and to avoid cardiac catheterization

GM crops and gender issues

Correspondence in the December issue by Jonathan Gressel not only states that gender issues in rural settings have not been adequately addressed with respect to weed control biotech but also asserts that such technology can increase the quality of life of rural women in developing countries. Improved weed control is a labor-saving technology that can result in less employment in a labor surplus rural economy. Often in rural areas, wage income is the main source of income and an important determinant of the quality of life, particularly where employment opportunities are generally limited. Apart from soil preparation, planting and weeding, harvesting is also 'femanual' work that can generate more employment if yields are higher. Biotech can enhance the quality of life of women but only if the technology is associated with overall generation of rural employment

Evaluation of crushing and energy absorption characteristics of bio-inspired nested structures

Mimicking anatomical structures like bone can aid in the development of energy absorbing structures that can achieve desirable properties. Accordingly, this study presents the analysis of tubular nested designs inspired by Haversian bone architecture. Based on this design philosophy, a total of 18 nested tube designs with various geometrical configurations were developed. Within each design, the effect of reinforcement walls on the crashworthiness performance is also analysed. A finite element model, validated using quasi-static experimental tests, was used to study the crashworthiness performance and progressive deformation of the nested system. Based on the results, a multi-criteria decision-making method known as Technique of Order Preference by Similarity to Ideal Solution (TOPSIS) was employed to determine the most suitable cross-section that features high energy absorption and low impact force. Consequently, the study identified a nested tube configuration that exhibits superior crashworthiness and high energy absorbing characteristics. The bio-inspired design methodology presented in this study allows the exploitation of variable nested geometries for the development of high-efficiency energy absorbing structures.Accepted versio

Coronary artery caliber in normal children and patients with Kawasaki disease but without aneurysms: An echocardiographic and angiographic study

A total of 110 children aged 3 months to 16 years underwent two-dimensional echocardiography of the coronary arteries. Forty-two normal subjects and 68 patients with Kawasaki disease were evaluated. All 68 patients with Kawasaki disease underwent selective coronary arteriography. The objectives of this study were to 1) develop a normal profile of the proximal left and right coronary arteries as to caliber and shape in infants, toddlers and children using echocardiography; 2) compare the dimensions and shape of the coronary arteries of patients with Kawasaki disease but no obvious aneurysms with those of the coronary arteries of normal children; and 3) develop criteria that would permit distinguishing a large but normal coronary artery from a true aneurysm in patients with Kawasaki disease.In the normal subjects and patients with Kawasaki disease, the caliber of the coronary arteries showed little variability from the ostium to 10 mm distally, and ranged in size from 2 mm in infants to 5 mm in teenagers. There was no significant difference between male and female subjects. The feature that distinguished the large but normal coronary artery without aneurysm from that with an aneurysm was its uniformity of caliber. Also, the caliber of the opposite coronary artery was generally at the lower limits of normal. It appears that the proximal coronary arteries of infants and children can be accurately assessed using high resolution two-dimensional echocardiography, and that sequential evaluation of subtle changes over time may be performed

Particle number concentrations and size distributions in the stratosphere : implications of nucleation mechanisms and particle microphysics

While formation and growth of particles in the troposphere have been extensively studied in the past two decades, very limited efforts have been devoted to understanding these in the stratosphere. Here we use both Cosmics Leaving OUtdoor Droplets (CLOUD) laboratory measurements taken under very low temperatures (205-223 K) and Atmospheric Tomography Mission (ATom) in situ observations of particle number size distributions (PNSDs) down to 3 nm to constrain nucleation mechanisms and to evaluate model-simulated particle size distributions in the lowermost stratosphere (LMS). We show that the binary homogenous nucleation (BHN) scheme used in most of the existing stratospheric aerosol injection (a proposed method of solar radiation modification) modeling studies overpredicts the nucleation rates by 3-4 orders of magnitude (when compared to CLOUD data) and particle number concentrations in the background LMS by a factor similar to 2-4 (when compared to ATom data). Based on a recently developed kinetic nucleation model, which gives rates of both ion-mediated nucleation (IMN) and BHN at low temperatures in good agreement with CLOUD measurements, both BHN and IMN occur in the stratosphere. However, IMN rates are generally more than 1 order of magnitude higher than BHN rates and thus dominate nucleation in the background stratosphere. In the Southern Hemisphere (SH) LMS with minimum influence of anthropogenic emissions, our analysis shows that ATom-measured PNSDs generally have four apparent modes. The model captures reasonably well the two modes (Aitken mode and the first accumulation mode) with the highest number concentrations and size-dependent standard deviations. However, the model misses an apparent second accumulation mode peaking around 300-400 nm, which is in the size range important for aerosol direct radiative forcing. The bimodal structure of accumulation mode particles has also been observed in the stratosphere well above tropopause and in the volcano-perturbed stratosphere. We suggest that this bimodal structure may be caused by the effect of charges on coagulation and growth, which is not yet considered in any existing models and may be important in the stratosphere due to high ionization rates and the long lifetime of aerosols. Considering the importance of accurate PNSDs for projecting a realistic radiation forcing response to stratospheric aerosol injection (SAI), it is essential to understand and incorporate such potentially important processes in SAI model simulations and to carry out further research to find out what other processes the present models might have missed.Peer reviewe

Chronic kidney disease referrals from general practitioners pre- and post National Institute for Health and Care Excellence guidance 2014.

Introduction: Mortality from chronic kidney disease (CKD) is increasing. Most patients die from cardiovascular disease and management of cardiovascular risks is key to prevent both mortality and progression to end-stage renal disease. In 2014, the National Institute of Health and Care Excellence (NICE) introduced guidance to help general practitioners (GPs) manage CKD patients. Aim: We aimed to determine the impact of the updated CKD guidance on CKD/cardiovascular risks optimisation and the timeliness of referral from the primary care. Methods: All new GP referrals to the Regional Renal Service in 2012 and 2016 were analysed. Data were collected on patient age, estimated glomerular filtration rate (eGFR) at referral, blood pressure (BP), smoking, body mass index, glycated haemoglobin (HbA1c; in diabetic patients) and lipid assessment. Results: A total of 486 new GP referrals were received in 2012, and 574 in 2016 (18% increase post NICE CKD guideline). Post NICE, fewer stage 4 and 5 CKD patients were being referred. But late referrals (eGFR <20 mL/min/1.73 m2) were not improved. BP control had improved. More patients had cholesterol-levels checked. The number of smokers and obese patients had not improved. Conclusion: Post NICE guidelines, GPs are better in optimising BP. Diabetes management and lifestyle modifications need further improvement

Normalised Mutual Information of High-Density Surface Electromyography during Muscle Fatigue

This study has developed a technique for identifying the presence of muscle fatigue based on the spatial changes of the normalised mutual information (NMI) between multiple high density surface electromyography (HD-sEMG) channels. Muscle fatigue in the tibialis anterior (TA) during isometric contractions at 40% and 80% maximum voluntary contraction levels was investigated in ten healthy participants (Age range: 21 to 35 years; Mean age = 26 years; Male = 4, Female = 6). HD-sEMG was used to record 64 channels of sEMG using a 16 by 4 electrode array placed over the TA. The NMI of each electrode with every other electrode was calculated to form an NMI distribution for each electrode. The total NMI for each electrode (the summation of the electrode&#039;s NMI distribution) highlighted regions of high dependence in the electrode array and was observed to increase as the muscle fatigued. To summarise this increase, a function, M(k), was defined and was found to be significantly affected by fatigue and not by contraction force. The technique discussed in this study has overcome issues regarding electrode placement and was used to investigate how the dependences between sEMG signals within the same muscle change spatially during fatigue

A computational model to investigate the effect of pennation angle on surface electromyogram of Tibialis Anterior

This study has described and experimentally validated the differential electrodes surface electromyography (sEMG) model for tibialis anterior muscles during isometric contraction. This model has investigated the effect of pennation angle on the simulated sEMG signal. The results show that there is no significant effect of pennation angle in the range 00 to 20o in the single fibre action potential shape recorded on the skin surface. However, the changes with respect to pennation angle are observed in sEMG amplitude, frequency and fractal dimension. It is also observed that at different levels of muscle contractions there is similarity between the relationships with Root Mean Square, Median Frequency and Fractal Dimension of the recorded and simulated sEMG signals