Recovery of Force Output and Electromyography from Trunk Muscles After Cyclic Passive Loading.

TITLE: RECOVERY OF FORCE OUTPUT AND ELECTROMYOGRAPHY FROM TRUNK MUSCLES AFTER CYCLIC PASSIVE LOADING Major Advisor: Michael W. Olson TITLE: RECOVERY OF FORCE OUTPUT AND ELECTROMYOGRAPHY FROM TRUNK MUSCLES AFTER CYCLIC PASSIVE LOADING Major Advisor: Michael W. Olson Continuous loading of the low back tissues results in modified neuromuscular and kinetic output during trunk extension efforts. It is believed that the viscoelastic behavior of these low back tissues is modified, but the ramifications of these loading schemes needs further study for longer durations. The purpose of this research project was to observe force output and muscle activation pattern changes during trunk extension efforts before and up to 60 minutes after passive cyclic loading of the lumbar spine during trunk flexion-extension exercise. Sixteen healthy male and female volunteers (20.3 ± 2.1 yrs, 1.63 ± 0.04 m, 50.2 ± 9.3 kg) participated in the study. An isokinetic dynamometer was used in performing a 10 min set of cyclic trunk flexion-extension at a preset velocity of 0.17rad/s through each participant’s range of trunk flexion from seated upright position. Participants performed maximum voluntary isometric contraction (MVIC) trunk extension efforts before, immediately after, and at 15 minute intervals (T15 – T60 ) for 60 min after cessation of the passive loading scheme. Maximum and average torque output, as well as surface electromyography (EMG) from thoracic (TP) lumbar paraspinal (LP), rectus abdominis (RA) and external oblique (EO) muscles (bilaterally), were recorded. One way ANOVAs were used to identify changes at each time period of testing compared to baseline values. Alpha was set at \u3c 0.05. Maximum and average torque measures did not change over time (p \u3e 0.05). Rate of force development did not change over time (p \u3e 0.05). Average EMG did not change over time (p\u3e0.05) in TP,LP and RA muscles. There was significant difference across time for the LEO muscle (p \u3c 0.04). Average EMG at T15 and T30 were significantly lower than the initial pre-loading values. Similarly, a significant difference was present in the right EO over time (p \u3c 0.01). Average EMG values at T15, T30 and T45 were significantly lower than at the initial pre-loading values. All peak EMG data during recovery were significantly reduced compared to the initial value all (p 0.05) Range of motion did not significantly change from pre to post trials. These data provide inconclusive results as to the force output and EMG modifications when the passive viscoelastic tissues are cyclically loaded in flexion-extension. There are indications of modifications in the EMG detected from EO, providing further potential evidence of neuromuscular modification to potentially compensate for increased compliance of the viscoelastic tissues

Teacher Knowledge and Learning In-situ: A Case Study of the Long Division Algorithm

The aim of the study reported in this paper was to explore and enhance experienced school mathematics teachers’ knowledge of students’ thinking, as it is manifested in practice. Data were collected from records of classroom observations, interviews with participating teachers, and weekly teacher-researcher meetings organized in the school. In this paper, we discuss the mathematical challenges faced by a primary school teacher as she attempts to unpack the structure of the division algorithm, while teaching in a Grade 4 classroom. Through this case study, we exemplify how a focus on mathematical knowledge for teaching ‘in situ’ helped in triggering a change in the teacher’s well-formed knowledge and beliefs about the teaching and learning of the division algorithm, and related students’ capabilities. We argue that in the context of educational reform, an analysis of knowledge demands placed on the teacher helps in understanding and supporting teachers’ work

DCE-MRI and parametric imaging in monitoring response to neoadjuvant chemotherapy in breast carcinoma : a preliminary report

Purpose: Neoadjuvant chemotherapy is recommended in patients with locally advanced breast cancer. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) enables evaluation of the tumour neovasculature that occurs prior to any volume change, which helps identify early treatment failures and allows prompt implementation of second-line therapy. Material and methods: We conducted a prospective study in 14 patients with histopathologically proven breast cancer. DCE-MRI data were acquired using multisection, T1-weighted, 3D vibe sequences with fat suppression before, during, and after IV bolus injection (0.1 mmol/kg body weight, Gadoversetamide, Optimark). Post-processing of dynamic contrast perfusion data was done with the vendor's Tissue 4D software to generate various dynamic contrast parameters, i.e. Ktrans, Kep, Ve, initial area under the time signal curve (IAUC), apparent diffusion coefficient (ADC), and enhancement curve. Patients underwent MRI examinations at baseline, and then after two cycles, and finally at completion of chemotherapy. Results: Based on Sataloff criteria for pathological responses, four patients out of 14 were responders, and 10 were non-responders. At the 2nd MRI examination, IAUC was significantly smaller in responders than in non-responders (p = 0.023). When the results of the first and second MRI examinations were compared, Kep decreased from baseline to the second MRI (p = 0.03) in non-responders and in responders (p = 0.04). This change was statistically significant in both groups. The ADC values increased significantly in responders from baseline to the third MRI (p = 0.012). Conclusions: In our study, IAUC and ADC were the only parameters that reliably differentiated responders from non-responders after two and three cycles of chemotherapy

FORMULATION AND IN VITRO CHARACTERIZATION SOLID SELF EMULSIFYING DRUG DELIVERY SYSTEM OF RAMIPRIL PREPARED BY ADSORPTION TECHNIQUE

Objective: The primary goal of the present work was to formulate solid self-emulsifying drug delivery systems (S-SEDDS) in order to improve the solubility of the highly lipophilic antihypertensive drug, ramipril. Methods: SEDDS are generally liquid form preparations obtained by homogeneously mixing oils, surfactants and co-surfactants along with drug component. Based on solubility studies Capmul PG8 NF, Gelucire 44/14 and Transcutol P were selected as oil, surfactant, co-surfactant respectively in order to prepare liquid SEDDS (L-SEDDS). Nine different liquid SEDDS were prepared and subjected to various evaluation tests in order to obtain optimized L-SEDDS. Finally, the optimized formulation was converted to S-SEDDS by physical adsorption technique using an inert carrier. Further, S-SEDDS were also subjected to solid state characterization. Results: Out of 9 different L-SEDDS, S9 formulation was optimized as it formed thermodynamically stable emulsion without any drug precipitation and phase separation on storage and also showed least globule size (22.56 nm). The optimized formulation was loaded onto inert carrier (Sylysia FCP 350) to obtain S-SEDDS. S-SEDDS showed acceptable flow properties. They were further processed for solid state characterization such as XRD, DSC and SEM and the results confirmed the transformation of native crystalline nature of drug to an amorphous state. FTIR analysis also confirmed no drug-excipient interaction. S-SEDDS showed improved in vitro dissolution behaviour of ramipril over that of pure drug. Conclusion: Ramipril S-SEDDS retained emulsification characteristics of L-SEDDS. Further, S-SEDDS was encapsulated in hard gelatin capsules and this formulation proved to have improved solubility for ramipril

Unusual Branching Pattern of the Lateral Cord of the Brachial Plexus Associated with Neurovascular Compression : Case report

The brachial plexus consists of a network of nerves that innervates the upper limbs and its musculature. We report a rare formation of the lateral cord of the brachial plexus observed during the dissection of a 47-year-old male cadaver at the Department of Anatomy, Vardhman Mahavir Medical College, New Delhi, India, in 2016. The lateral cord was exceptionally long with twin lateral pectoral nerves and twin lateral roots of the median nerve. The proximal lateral root of the median nerve was thin in comparison to the medial root of the median nerve. The distal lateral root of the median nerve was thicker and followed an unusual course through the coracobrachialis muscle. In the lower third of the arm, the median nerve and the brachial artery—along with its vena comitans—spanned through the brachialis muscle. Surgeons, anaesthesiologists, radiologists and anatomists should be aware of such anatomical variations as they may result in neurovascular compression

Investigating the influence of ultrasound pre-treatment on drying kinetics and moisture migration measurement in Lactobacillus sakei cultured and uncultured beef jerky

Low Frequency-Nuclear Magnetic Resonance (LF-NMR) was employed to elucidate changes in water distribution in cultured (Lactobacillus sakei) and uncultured beef jerky samples subjected to ultrasound pre-treatment. Ultrasound pre-treatment at frequencies of 25, 33 and 45 kHz for 30 min, followed by marination (18 h) was carried out for both cultured and uncultured jerky samples. Among the various kinetic models assessed, the Wang and Singh model provided the closest fit to the drying experimental data, with high R2 (≥0.994), low RMSE (≤0.023) and low AICc (100 ms (T22), respectively. Results presented in this study demonstrates that the ultrasound effect on drying behaviour was frequency dependent and that LF-NMR can be employed to evaluate moisture mobility and drying degree of beef jerky

Nanoscale Defect Formation on InP(111) Surfaces after MeV Sb Implantation

We have studied the surface modifications as well as the surface roughness of the InP(111) surfaces after 1.5 MeV Sb ion implantations. Scanning Probe Microscope (SPM) has been utilized to investigate the ion implanted InP(111) surfaces. We observe the formation of nanoscale defect structures on the InP surface. The density, height and size of the nanostructures have been investigated here as a function of ion fluence. The rms surface roughness, of the ion implanted InP surfaces, demonstrates two varied behaviors as a function of Sb ion fluence. Initially, the roughness increases with increasing fluence. However, after a critical fluence the roughness decreases with increasing fluence. We have further applied the technique of Raman scattering to investigate the implantation induced modifications and disorder in InP. Raman Scattering results demonstrate that at the critical fluence, where the decrease in surface roughness occurs, InP lattice becomes amorphous.Comment: 18 pages, 9 figure