BioMedical Physics

Cycling exercise-based on functional electrical stimulation (FES) for disabled individuals-is achieved by stimulating single muscle group, the quadriceps, with the help of a new assist mechanism represented by a solid disc flywheel equipped with an electrical clutch. Fuzzy logic based closed-loop control method is implemented to obtain a stable cycling cadence by i) controlling the stimulation intensity on the muscle and ii) managing the engagement of the flywheel mechanism. To achieve better results, several crank positionswith different gear ratios between the crank and the flywheel-are tested and analyzed. To obtain the optimal design parameters, a multi-objective genetic algorithm (MOGA) approach is adopted towards maximizing the cycling efficiency and minimizing the cadence error. A comparison with the results reported in the literature reveals the superiority of the proposed design to limit the cadence error to ±5 rpm for 35 rpm desired speed. Moreover, the results demonstrate that the designed control approach with the proposed assist mechanism is robust to changes in muscle force due to muscle fatigue. Additionally, the introduced control approach with the new assist mechanism is promoting bounded tracking of the desired speed and prolonging FES-cycling training by stimulating the quadriceps muscle group only.

A superluminal quantum-vortex model of the electron and the positron is produced from a superluminal double-helix model of the photon during electron-positron pair production. The two oppositely-charged (with Q = ±e sqrt (2/α) = 16.6e) open-helix spin-½ half-photons compose the double-helix photon. These half-photons separate and curl up their separated superluminal single-helical trajectories to form an electrically-charged superluminal closed-helix spin-½ quantum-vortex electron model and a corresponding positron model. The helical radius and the Dirac equation's zitterbewegung angular frequency of the quantum vortex electron and positron models equal the helical radius and zitterbewegung angular frequency of the two spin-½ half-photons, each of energy E = mc^2 , that composed the double-helix photon model of energy E = 2mc^2 from which the electron and positron models were produced. The photon and electron models are also compatible when a photon of energy E > 2mc^2 produces a relativistic electron-positron pair. Implications of the quantum vortex electron model for electron stability are discussed.

The ability of Minkowski Functionals to characterize local structure in different biological tissue types has been demonstrated in a variety of medical image processing tasks. We introduce anisotropic Minkowski Functionals (AMFs) as a novel variant that captures the inherent anisotropy of the underlying gray-level structures. To quantify the anisotropy characterized by our approach, we further introduce a method to compute a quantitative measure motivated by a technique utilized in MR diffusion tensor imaging, namely fractional anisotropy. We showcase the applicability of our method in the research context of characterizing the local structure properties of trabecular bone micro-architecture in the proximal femur as visualized on multi-detector CT. To this end, AMFs were computed locally for each pixel of ROIs extracted from the head, neck and trochanter regions. Fractional anisotropy was then used to quantify the local anisotropy of the trabecular structures found in these ROIs and to compare its distribution in different anatomical regions. Our results suggest a significantly greater concentration of anisotropic trabecular structures in the head and neck regions when compared to the trochanter region (p < 10-4). We also evaluated the ability of such AMFs to predict bone strength in the femoral head of proximal femur specimens obtained from 50 donors. Our results suggest that such AMFs, when used in conjunction with multi-regression models, can outperform more conventional features such as BMD in predicting failure load. We conclude that such anisotropic Minkowski Functionals can capture valuable information regarding directional attributes of local structure, which may be useful in a wide scope of biomedical imaging applications.

Escherichia coli (abbreviated as E. coli) is a common bacterium both in daily life and scientific researches. In order to demonstrate the biophysical properties of Escherichia coli, the 3D model and simulation of E. coli are built based on Blender, helping with the visualization. First, a brief introduction to Blender explains why it's chosen as the modelling software and demonstrates the advantages of Blender by comparison; next, the whole process of how the model is built through basic shapes and modifiers is provided step by step. Lastly, several C# scripts in Unity are written to make the model move as real Escherichia coli in a low Reynolds number environment to simulate the behaviour of the cell in line with a given motion mode. The final result manifests the above methods have a great performance in the construction and simulation of E. coli, which could offer ideas for further study of the simulation of the microorganism.

There is enormous evidence that the initiation and growth of atherosclerosis is highly influenced by hemodynamic factors. In this study, hemodynamic factors in the following patient specific 3D carotid artery models were studied: i) normal, ii) stenosis (with plaque near to bifurcation of internal carotid artery (ICA)), and iii) surgical model (plaque with surgically fitted Palmaz–Schatz stent). The 3D model of the carotid artery was formed from CT image of a patient through a commercial software MIMICS. The geometrical measurement taken from the 3D model was used to form its CAD model using CATIA software. The CAD model was meshed in ANSYS ICEM CFD module. The inlet- and outlet- boundary conditions were defined and material properties were given in CFX-Pre module of ANSYS. Then the solver input file was given to CFX solver manager for performing computational fluid dynamics (CFD) on the model. The outputs of the CFD analysis were observed in CFD-Post. The wall shear stress and blood velocity were greater both at near the bifurcation and at bend of the carotid artery model. The abnormal model is characterized by high wall shear stress in the stenosed portion which indicates greater probability of growth of plaque. Disturbed flow patterns and oscillating velocity indicate that the vulnerability of plaque formation is high in such places. The hemodynamic values have come back near to normal values in the carotid model fitted with stent. The observed variations in hemodynamic factors in the carotid artery with plaque surgically fitted with stent were compared to its normal model. This information can be used to predict restenosis in future.

Recent days Computer-aided design and image processing techniques are one of the most emerging useful tools for analysis of models in various medical, industrial and research areas. In medical field for the diagnosis of various diseases in vivo techniques including biochemical test, enzymatic tests are needed for continuous monitoring of patients. These diagnosis procedures are time consuming and inconvenient for patients. Therefore Computer assisted designing and image processing techniques are most promising non invasive tools for faster diagnosis and useful tool for designing of biomedical implants. In this paper portal vein was segmented from patient’s Liver computed tomography (CT) image by dedicated software. A Liver’s CT image of 38 year old Indian male patient’s was collected and by using imaged based software MIMICS (Materialise’s Interactive Medical Image Control System, Belgium) 3D model of HPV (hepatic portal vein) was obtained and Solid Work Professional (Dassault Systems Solid Works Corporation, USA) software was used for designing of normal portal vein’s 3D model and various portal vein diseased models including minor right portal vein thrombosis ( 19-20% reduction in medial region of vein), severe right portal vein thrombosis (20-22% reduction in medial and distal region of vein), minor left portal vein thrombosis (19-20% reduction in medial region of vein, severe right portal vein
thrombosis(20-22% reduction in medial and distal region of vein), left aneurysm (150-200 % increase of medial region).These models can be used for designing for implants and analysis of portal vein’s disorder like portal thrombosis, and portal aneurysm which are main cause of portal hypertension and also useful for surgeon for planning surgery and also helpful for understanding of portal vein hemodynamic (pressure, velocity, wall shear force)

Phyllanthus emblica  posses a vast ethnomedicinal history and
represents a large group of phytochemical reservoir of medicinal
uses. It is one of the ingredients used from time immemorial in
various ancient literatures like in “Ayurveda” and “Charka
Samhitha” as a potential ingredient for various ailments. The fruit
is studied for various phyto chemical constituents  like rich in
quercetin, gallic acid, tannins, flavonoids, pectin and Vitamin C
and also contains various polyphenolic compounds. A wide range
of phytochemical components from this plant have shown proven
results for biological activities like terpenoids,  alkaloids,
flavonoids and tannins. Many pharmacological studies also have
exhibited proven results for antioxidant, anticarcinogenic,
antitumour, antigenotoxic, antiinflamatory activities supporting its
traditional uses. In view of these studies the present work has been
focused on the GC–MS analysis of ethyl acetate extract of the bark
portion of the  P. emblica  which could be a possible source of
extracting the therapeutically useful products.

In India, number of people with type 2 Diabetes Mellitus (DM) would be 87 million by the year 2030. DM disturbs autonomic regulation of skin microcirculation, and causes decrease in resting blood flows through the skin. The skin blood flow has a major effect on its temperature. The aim of the study was to evaluate changes of skin temperature of all parts of the body and serum asymmetric dimethylarginine, ADMA (μmol/L) in type-2 DM Indian patients. Group-I: Normal (n=17; M/F: 10/15, mean±SD= 43.2±9.4 years); Group-II: Type-2 DM without cardiovascular (CV) complications (n=15; M/F: 10/7, mean±SD= 46.3 ± 14.0 years); Thermograms of all parts of the body were acquired using a non-contact infrared (IR) thermography camera (ThermaCAM T400, FLIR Systems, Sweden). Blood parameters and thyroid hormone were measured biochemically. Indian diabetic risk score (IDRS) was calculated for each subject. In type-2 DM patients without CV group (n=15), there was a statistically significant (p=0.01) negative correlations between HbA1c and skin temperature of eye and nose (r= -0.57 and r= -0.55 respectively). ADMA was correlated significantly (p=0.01) with HbA1c (r=0.65) and estimated average glucose, eAG (r=0.63). In normal subjects, mean minimum and maximum values of skin temperatures were observed at posterior side of sole (26.89°C) and ear (36.85°C) respectively. In type-2 DM without CV, mean values of skin temperature in different parts of the body from head to toe were lesser than those values in control group; but this decreases were statistically significant in nose (32.66 Vs 33.99°C, p=0.024) as well as in tibia (32.78 Vs 33.13°C, p=0.036) regions.

Background: Lifespan and its quality can be improved by early diagnosis of osteoporosis. Analysis of
trabecular boundness on digital hip radiographs could be useful for identifying subjects with low bone
mineral density (BMD) or osteoporosis. The main aim of our study was to evaluate the ability of a kernelbased
support vector machine (SVM) with respect to diagnosis and add to knowledge about the
trabecular features of digital hip radiographs for identifying subjects with low BMD.
Method: In this paper we present an SVM kernel classifier-based computer-aided diagnosis (CAD) system
for osteoporotic risk detection using digital hip radiographs. Initially, the original radiograph was
intensified, then trabecular features such as boundness, orientation, solidity of spur and delta were
evaluated and radial bias function (RBF) based discrimination was manifested. The next step was the
evaluation of the diagnostic capability of the proposed method in order to spot subjects with low BMD at
the femoral neck in 50 (50.7714.3 years) South Indian women with no previous history of osteoporotic
fracture. Out of 50 subjects, 28 were used to train the classifier and the other 22 were used for testing.
Results: The proposed system has achieved the highest classification accuracy documented so far by means
of a fivefold cross-validation analysis with mean accuracy of 90% (95% confidence interval (CI): 82 to 98%);
sensitivity and positive predictive value (PPV) were 90% (95% CI: 82 to 98%) and 89% (95% CI: 81 to 97%),
respectively. Pearson's correlation was observed at the level of po0.001, between extracted image trabecular
features with age and BMDs measured by dual energy x-ray absorptiometry (DXA). Extracted image features
also demonstrated significant differences between high and low BMD groups at the level of p<0.001.
Conclusion: Our findings suggest that the proposed CAD system with SVM would be useful for spotting
women vulnerable to osteoporotic risk.

High-intensity focused ultrasound guided by magnetic resonance imaging has been extensively evaluated during the past decade as a clinical alternative for thermal ablation of tumor tissue. However, the maximal ablation volume is limited by the extensive treatment duration resulting from the small size of the focal point as compared to the average tumor size. Volumetric sonication has been shown to efficiently enlarge the ablated volume per sonication, but remains limited by the temperature increase induced in the skin and fat layers. In this study, multiplane MR thermometry is proposed for monitoring the near-field temperature rise in order to prevent related unintended thermal damage.
The method was evaluated by performing sonications in the thigh muscle of 11 pigs maintained under general anesthesia. Volumetric ablations were performed by steering the focal point along trajectories consisting of multiple outward-moving concentric circles. Near-field heating was characterized with MR temperature maps and thermal dose maps. The results from the MR measurements were compared to simulations.
In this study, the measured maximum temperature rise was found to correlate linearly with the surface energy density within the near field of the beam path with a slope of 4.2 K mm2/J. This simple linear model appears to be almost independent of the trajectory pattern and the sonication depth. The safety limit to avoid lethal damage of the subcutaneous tissues of the porcine thigh was identified to be an absolute temperature of 50 degrees C, corresponding to a surface energy density of 2.5 J/mm2 at 1.2 MHz.
A linear relationship can be established to estimate the temperature increase based on the chosen power prior to ablation, thereby providing an a priori safety check for possible excessive near-field heating using a known surface energy density threshold. This method would also give the clinician the possibility to abort the sonication should excessive near-field temperature rise be seen before fat layer damage or skin burns are inflicted.

Tetracycline belongs to one of the extracellular pr oduced polyketide antibiotics having hydrophilic properties. Statistical based optimization, Plac kett–Burman design (PBD) and response surface methodology (RSM) were occupied to screen and optimize the medium co nditions for the production of tetracycline from Streptomyces aur eofaciens NCIM 2417, using solid state fermenta tion. pineapple peel waste was used as both the cur ious solid support and carbon and nitrogen sourc es and inorganic salts for the growth of Streptomyces aureofaciens NCIM 2417. Based on the positive influence of the half normal plot obtained from PBD on tetracycline production, three medium conditions – peanut meal, incubation period and s oluble starch were screened. Central composite design (CCD) was occupied using these three medium conditions at five levels, for advance optimization, and the second order polynomial equation was derived, based on the experiment al data. Response surface methodology showed ...

Objective:The aim of this study was to evaluate the progression of arthritis in a complete Freund’s adjuvant (CFA)-induced Wistar rat model and to monitor inflammatory arthritis activity using thermal imaging compared with histopathology.Methodology: Fifteen adult male Wistar rats were studied in an adjuvant induced arthritis model by the injection of complete Freund’s adjuvant in the right hind limb and right forelimb, respectively, with the left limbs used as controls. Thermal image analysis based on skin temperature measurement, radiographic analysis based on erosion, limb circumference measurement, and histopathological evaluation were performed.Results. The average skin temperature difference on the arthritis-induced side and control for both the forelimb and hind limb were found to be 1.09 °C and 0.98 °C, respectively. Pearson correlation analysis revealed that skin surface temperature was positively correlated with the arthritis severity score (forelimb: r=0.64, hind limb: r=0.66, p<0.05).A significant correlation also existed between thermal imaging temperature and visual scoring of X-ray (forelimb: r=0.56, hind limb: r=0.67, p<0.05). Conclusion:Thermal imaging measurements correlated with arthritis severity score,radiological score, and ankle diameters. Hence, thermography could be used to diagnose and analyze inflammatory activity of arthritis at the preclinical stage.

For hospitalized patients with pulmonary conditions, the onset of respiratory decline can occur unnoticed, due to the absence of a way to continuously and noninvasively monitor lung condition. Based on the relationship between lung volume and pleural pressure, we hypothesized that the time delay (∆t) between the start of a respiratory cycle and the occurrence of lung sounds associated with inspiration would correlate with lung volume. Additionally, we developed a research tool, consisting of a respiration belt, digital stethoscope, data collection system and MATLAB algorithm, to measure this delay. We conducted a feasibility study with three healthy individuals that involved safely manipulating lung volume, through subject position and activity, and plotting ∆t against volume measurements obtained via spirometry. The results indicated that ∆t was measurable and changed with lung volume and, therefore, has the potential to serve as a lung condition monitoring tool. Clinical Relevance-Developing this metric and measurement method into a noninvasive monitoring tool would provide means to better detect declining pulmonary function and intervene earlier and more appropriately.

Viruses have threatened animal and human lives since a long time ago all over the world. Some of these tiny particles have caused disastrous pandemics that killed a large number of people with subsequent economic downturns. In addition, the quarantine situation itself encounters the challenges like the deficiency in the online educational system, psychiatric problems and poor international relations. Although viruses have a rather simple protein structure, they have structural heterogeneity with a high tendency to mutation that impedes their study. On top of the breadth of such worldwide worrying issues, there are profound scientific gaps, and several unanswered questions, like lack of vaccines or antivirals to combat these pathogens. Various detection techniques like the nucleic acid test, immunoassay, and microscopy have been developed; however, there is a tradeoff between their advantages and disadvantages like safety in sample collecting, invasiveness, sensitivity, response time, etc. One of the highly resolved techniques that can provide early-stage detection with fast experiment duration is plasmonics. This optical technique has the capability to detect viral proteins and genomes at the early stage via highly sensitive interaction between the biological target and the plasmonic chip. The efficiency of this technique could be proved using commercialized techniques like reverse transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) techniques. In this study, we aim to review the role of plasmonic technique in the detection of 11 deadliest viruses besides 2 common genital viruses for the human being. This is a rapidly moving topic of research, and a review article that encompasses the current findings may be useful for guiding strategies to deal with the pandemics. By investigating the potential aspects of this technique, we hope that this study could open new avenues toward the application of point-of-care techniques for virus detection at early stage that may inhibit the progressively hygienic threats.

Biological effects of microwaves or in general any EM irradiation is mostly analysis in terms of thermal effects. On this ground mostly exposures from mobile phone towers are said to be safe but some of the field studies reports strongly support the ill effects associated with it. Scientists and researchers are not of clear opinion about the mechanism, how the effects can be visualized. In the study reported here, the behavior of the nerve conduction is realized is in the form of electrical circuit, basically in the form of RC Transmission line. This paper shows simulation results of the effect of the continuous exposure of External EM Field on the nervous. Simulation is based on the MATLAB ® and analysis of effect of mixing of AC signal with the membrane potential is done. Another simulation result of the affect of variation of frequency on the conduction behavior is also simulated in this paper. Results indicate that the reported bio-effects may be not of direct nature, like in case of ionic radiations but may be due to the malfunctioning of the never communication network due to EM-exposure. Further development of the experimental model is under process.

Monitoring changes in non-ionizing radiofrequency electromagnetic waves as they traverse the brain can detect the effects of stimuli employed in cerebrovascular autoregulation (CVA) tests on the brain, without contact and in real time. CVA is a physiological phenomenon of importance to health, used for diagnosis of a number of diseases of the brain with a vascular component. The technology described here is being developed for use in diagnosis of injuries and diseases of the brain in rural and economically underdeveloped parts of the world. A group of nine subjects participated in this pilot clinical evaluation of the technology. Substantial research remains to be done on correlating the measurements with physiology and anatomy. Medical imaging for diagnosis is not available to a large segment of the world population. This medical problem cannot be ameliorated through well intentioned donations of state of the art medical equipment, because these devices required trained physicians, who are not available to service that segment of the population. This study is part of our decade long international collaboration effort aimed at developing affordable medical diagnosis technologies to reduce medical care cost in remote and impoverished parts of the world 1–7,45–49. Our goal is to develop medical technologies that, while using advanced scientific concepts, are inexpensive, robust and do not require advanced medical training for use. In this study we introduce a new technology that is inexpensive and does not require advanced medical training , for possible use in the diagnosis of cerebrovascular diseases. The physiological basis of the technology is the phenomenon of cerebrovascular autoregulation (CVA). The CVA concept is a simplified term that describes the complex response of the cerebrovascular blood flow (CBF) to the interplay between the physiological and functional needs of the brain metabolism and those of the rest of the body 8–12. A number of mechanisms have evolved to safeguard the brain against dangerous fluctuations in blood supply and optimize the response to metabolic requirements of the brain. They include: metabolic regulation, myogenic regulation and, neurogenic regulation 13. The overall effect is the CVA. Many excellent reviews of this field exist, e.g. 8,12–18. Evaluation of CVA is a valuable tool for diagnosis of the normal function of the brain and of various diseases related to the brain and to blood flow 15,19,20. Cerebral autoregulation can be characterized in a static and dynamic context, by assessing static cerebrovas-cular autoregulation (sCVA) and dynamic cerebrovascular autoregulation (dCVA). While our technology can be applied to both sCVA and dCVA based diagnosis, the focus of this paper is the dCVA. The concept of dynamic CVA, is based on the observation that when the brain normal homeostasis is disturbed by a sudden change, the CBF adjusts rapidly, usually within 2–10 seconds, to a new steady state value 13,21. The principle of dCVA measurement is based on evaluation of the stimulus-response process that aims to maintain adequate and stable cerebral

Aims:  To study protease production from four Bacillus species.
To optimize the production of extracellular protease by testing
various environmental and nutritional factors and its application as
a contact lens cleanser.
Methodology: The assay was carried out in duplicates. Cultures of
Bacillus subtilis, Batcillus licheniformis, Bacillus thermophilus,
and  Bacillus cereus  were used for Protease production and assay.
Sterile Bushnell  –  Hass medium containing 1% casein was used.
The clear zone of casein hydrolysis indicated protease secretion.
Protease assay was done using modified sigma protocol for
enzymatic assay of protease. Effect of incubation time, pH,
temperature and aeration on protease production was studied.
Diameter of colony and zone of clearance was measured and Cx
ratio was calculated. The best protease producer was selected.
Extracted and crude protease enzymes were added to artificial tear
solution prepared with 0.2% lysozyme. Enzyme treatment was
done for 10, 30, 60 and 90 min at optimum temperatures of
respective enzymes. Light  transmission readings were recorded
using visible range spectrophotometer at 285 nm.
Results:  All four species of Bacillus produced protease enzyme.
Bacillus subtilis (Cx ratio=6) was the best protease producer. 37
o
C
temperature, 48 hrs of incubation and pH 7.5 was optimum for
maximum production of protease from Bacillus subtilis. Optimum
temperature and pH for the crude enzyme activity was 40ºC and 8.
The optimum ammonium sulfate fractionation (40% (w/v)
saturation) showed 4.76 fold increase in the specific activity of the
crude extract. Protein solution was degraded by purified enzyme in
30 min whereas crude enzyme required 60 min.
Conclusion:  Protease enzyme extracted from  Bacillus subtilis
showed good activity against artificial tear solution.

Objectives: The aim of the present study was to compare and correlate body composition measurements and bone mineral density in patients with rheumatoid arthritis (RA) and age-matched controls to identify the possible prediction factors for low bone mass, fractures, and body composition changes.
Methods: Ninety-two RA patients and 92 age- and sex-matched healthy controls were included for the study. A health assessment questionnaire (HAQ) score, disease activity score - (DAS 28), forearm bone mineral density (BMD) determined by dual energy x-ray absorptiometry (DXA), estimated heel BMD based on quantitative ultrasound and  body composition parameters were analyzed in  both RA patients and controls.
Results: Body fat mass (BFM) differed significantly between RA patient group (26.37±10.05 (kg)) and controls (30.11±8.64 kg, p<0.05). The Fat free mass (FFM) was also significantly different between RA patients (37.63±9.82 kg) and controls (42.97±6.68 kg, p<0.01). Forearm BMD and estimated heel BMD was significantly higher in controls (0.377±0.04 g/cm2, 0.493±0.08 g/cm2), than in RA patients (0.320±0.13 g/cm2 , 0.452±0.10 g/cm2;  p<0.01 and  p<0.05, respectively). The Fat free mass (FFM), muscle mass (MM), segmental muscle mass (SMM) was significantly correlated with the estimated  heel BMD and forearm BMD.
Conclusions: These findings indicated that the body composition measurements might be useful for predicting bone mineral density (BMD) in RA patients. High RA activity was found to be  associated with reduced function, and altered body composition and BMD.

In the present study, 1-(3-methoxy-phenyl)-3-naphthalen-1-yl-propenone (MPNP) is synthesized and characterized by several experimental techniques such as Fourier transform-infrared spectroscopy (FT-IR), FT-Raman, NMR and UV− vis spectral methods. The similar techniques are also investigated by the computational method using Gaussian software. The density functional theory (DFT) method is used to obtain the optimized structure using the B3LYP/6-311+ +G(d,p) basis set. This optimization procedure of the molecule gives the minimum energy confirmation of the structure. The computed geometrical parameters are compared with experimental data. The experimental FT-IR and FT-Raman spectra of MPNP are obtained in the regions 4000−400 and 4000−50 cm −1 respectively. The detailed vibrational assignments of the molecule are obtained with the support of potential energy distribution. The theoretical NMR (1 H and 13 C) analysis is conducted by the GIAO method for its structural characterization and compared with experimental chemical shifts. The experimental UV−vis spectrum is obtained in the dimethyl sulfoxide solvent and compared with the theoretically computed spectrum by the time-dependent DFT method. In addition to these studies, other analyses such as nonlinear optical, natural bonds orbital, frontier molecular orbital, molecular electrostatic potential, and NCI have been conducted to understand the nature of the molecule. The title molecule is docked and also the drug-likeness, ADMET studies were carried out. The RBD domain bound to the ACE2 receptor during the fusion makes spike glycoprotein an elusive therapeutic target in SARS-CoV-2 infection.

The research on all optical communication is going on all around the world to meet the high demand of data and telecommunication. Laser which was invented for emitting electromagnetic radiation is the most important component in optical communication. In this study we calculate the differential quantum efficiency of a DR(Distributed Reflector laser) with wire like active region. The internal quantum efficiency is shown to be a strong function of cavity length. The results for single and multiple quantum well structures are compared.

L'attuale situazione economica, politica e sociale richiede a tutti coloro che operano nella Sanità parti-colari sforzi per cercare di ideare e mettere in atto nuovi modelli organizzativi e gestionali, sperimentando nuove forme di interazione tra chi ha idee e chi ha le capacità di realizzarle. L'interazione tra i ricer-catori e le aziende, tuttavia, non è sempre agevole per una mancanza di una lingua comune. " L'Accademia delle Idee " è un nuovo progetto della Società Italiana di Nefrologia (SIN) per rispondere a questa proble-matica. Il fine di questo progetto è quello di consentire ai giovani ricercatori (età inferiore a 40 anni) di poter interagire in modo proficuo con le aziende e di fornire il supporto tecnico necessario per la realiz-zazione di uno studio di fattibilità (business plan) che possa attirare eventuali investimenti di aziende ope-ranti nell'ambito sanitario. In questo articolo saranno presentati i principi, la metodologia e le tempistiche de " L'Accademia delle Idee ".

The combination of anemia in malarial infestations  has been well
documented  in  literature.  But  an  immune  hemolytic  anemia
developing within days of treatment for Plasmodium vivaxmalaria
has  seldom  been  reported.  We  present  a  case  of  a  patient  with
vivax malaria who developed severe anemia and jaundice on day
seven  of  initiating  treatment  with  artesunate;  necessitating
expedient  measures.  This  case  highlights  the  importance,  yet
under-reported  association  of  Plasmodium  vivax malaria  and
immune-mediated hemolysis.

OBJECTIVES i) To collect normative data for proximal femur bone mineral density (BMD) in South Indian women using dual energy X-ray absorptiometry (DXA) and ii) to study the rate and significance of hip bone mineral loss with advancing age in this population. MATERIAL AND METHODS Forty five women, whose age ranged from 16 to 84 years were studied. This sample was drawn randomly from general medical practice at KJ Hospital, Chennai, South India during November, 1997 to April, 1998. Of these 45 cases, 21 were pre-menopausal (mean +/- SD age = 30.9+/-8.8 years) and 24 post-menopausal (mean +/- SD age = 62.1+/-11.0 years). Subjects with secondary bone diseases were excluded. Also excluded were those taking any drugs known to affect calcium metabolism e.g., thiazide diuretics, oestrogen and calcium. Subjects were divided into seven decadal age groups from 15-24 years to 75-84 years. BMD of the right proximal femur was evaluated using a QDR-1000 DXA bone densitometer (Hologic Inc., Waltham, Massachusetts, USA). Data analysis was done with SPSS/PC statistical software package. RESULTS Linear regression analysis showed significant (p < 0.001) negative correlations between all hip BMD variables at different regions of interest and patient's age. Relative to that at 30 years of age, rates of BMD loss in the neck of femur, trochanter, intertrochanter, total hip and Ward's triangle were 0.68%, 0.65%, 0.58%, 0.61% and 1.05% per annum respectively. Over the age of 65 years, the above mentioned regions BMD decreased by 0.91%, 0.84%, 0.72%, 0.78% and 1.66% per annum respectively. CONCLUSION Normative data for proximal femur BMD in South India women have been evaluated and it may prove useful for diagnosing osteoporosis in the women of South India.

Tetracycline belongs to one of the extracellular produced polyketide antibiotics having hydrophilic properties. Statistical based optimization, Plackett–Burman design (PBD) and response surface methodology (RSM) were occupied to screen and optimize the medium conditions for the production of tetracycline from Streptomyces aureofaciens NCIM 2417, using solid state fermentation. pineapple peel waste was used as both the curious solid support and carbon and nitrogen sources and inorganic salts for the growth of Streptomyces aureofaciens NCIM 2417. Based on the positive influence of the half normal plot obtained from PBD on tetracycline production, three medium conditions – peanut meal, incubation period and soluble starch were screened. Central composite design (CCD) was occupied using these three medium conditions at five levels, for advance optimization, and the second order polynomial equation was derived, based on the experimental data. Response surface methodology showed that the ...

The aim of this work was to evaluate low bone mass using the feed-forward neural network (NN) with good accuracy
taking into account the forearm and heel bone mineral density (BMD) as well as total body composition variables. A total
number of 162 subjects including 88 women (mean 􀁲 SD age = 37.7 􀁲 15.2 years) and 74 men (mean 􀁲 SD age=31.3 􀁲 10.9
years) were studied. In each subject, BMD (g cm-2) at forearm and heel using peripheral dual-energy X-ray absorptiometry
(pDXA) and total body composition variables by multifrequency bioelectrical impedance analyzer were measured. The
measured forearm BMD was used to estimate femur neck BMD by DXA using the published formula. Based on its T-score
value, subjects were classified as normal and low bone mineral mass groups separately. In women, it was found that the
forearm BMD was positively correlated with body fat percentage (r=0.327; p<0.001). It was observed that 27% of women
and 15% of men were affected by low bone mass. In the NN modelling, the following 10 measured variables were used in
men and women separately: i) BMI ((kg/m2); ii) average forearm BMD (g/cm2); iii) average heel BMD (g/cm2); iv) body fat
(%); v) muscle mass (kg); vi) visceral fat index; vii) bone mineral mass (kg); viii) total body water, TBW (%); ix) basal
metabolic rate, BMR (kCal); and x) metabolic age (years). Analysis of low bone mineral mass evaluation using NN
projected an accuracy of 87.5% and 85.1% in women and men population, respectively. With the aid of BMD at peripheral
skeletal sites and total body composition variables, low bone mass can be evaluated with good accuracy.

Combining biosensors with nanoscience provides great advantages such as being label-free and real time, highly sensitive, and small in size, as well as providing a low limit of detection and integration to other systems. That is why plasmonics finds various applications in drug detection, food safety, agriculture, photothermal therapy, etc. In this paper, we have fabricated a two-dimensional plasmonic grating biosensor using a soft lithography technique, which has eliminated some disadvantages of conventional plasmonic structures like expensive fabrication cost, inflexibility, and lack of mass production. On the other hand, we benefited from infrared neural stimulation for regulating membrane depolarization, which was based on photothermal mechanism and provided a contact-free and high spatial/temporal resolution. Eventually, the membrane depolarization of two different cell types of Hep G2 and mesenchymal stem cells cultured on two-dimensional plasmonic structure has been investigated under infrared neural stimulation. After preparing the soft plasmonic crystal, its reflection spectra and respective ellipsometry parameters were analyzed before and after cell culture with/without stimulation (near-infrared immune region ∼1450 nm). By comparing the obtained ellipsometry results for HEP G2 and mesenchymal stem cells, it is observed that the behavior of two cell types with respect to IR stimulation was the same as well as providing us the possibility of distinguishing the level of membrane depolarization under various stimulating frequencies. The strength of this integrated system for membrane depolarization detection has been shown experimentally, which can open new avenues toward neuroplasmonic application in the future.

Combining biosensors with nanoscience provides great advantages such as being label-free and real time, highly sensitive, and small in size, as well as providing a low limit of detection and integration to other systems. That is why plasmonics finds various applications in drug detection, food safety, agriculture, photothermal therapy, etc. In this paper, we have fabricated a two-dimensional plasmonic grating biosensor using a soft lithography technique, which has eliminated some disadvantages of conventional plasmonic structures like expensive fabrication cost, inflexibility, and lack of mass production. On the other hand, we benefited from infrared neural stimulation for regulating membrane depolarization, which was based on photothermal mechanism and provided a contact-free and high spatial/temporal resolution. Eventually, the membrane depolarization of two different cell types of Hep G2 and mesenchymal stem cells cultured on two-dimensional plasmonic structure has been investigated under infrared neural stimulation. After preparing the soft plasmonic crystal, its reflection spectra and respective ellipsometry parameters were analyzed before and after cell culture with/without stimulation (near-infrared immune region ∼1450 nm). By comparing the obtained ellipsometry results for HEP G2 and mesenchymal stem cells, it is observed that the behavior of two cell types with respect to IR stimulation was the same as well as providing us the possibility of distinguishing the level of membrane depolarization under various stimulating frequencies. The strength of this integrated system for membrane depolarization detection has been shown experimentally, which can open new avenues toward neuroplasmonic application in the future.