1,755 research outputs found
Transmission of image data over digital networks involving mobile terminals
There is a growing demand for data transmission over digital networks involving mobile terminals. An important class of data required for transmission over mobile terminals is image information such as street maps, floor plans and identikit images. This sort of transmission is of particular interest to the service industries such as the Police force, Fire brigade, medical services and other services. These services cannot be applied directly to mobile terminals because of the limited capacity of the mobile channels and the transmission errors caused by the multipath (Rayleigh) fading. In this research, transmission of line diagram images such as floor plans and street maps, over digital networks involving mobile terminals at transmission rates of 2400 bits/s and 4800 bits/s have been studied. A low bit-rate source encoding technique using geometric codes is found to be suitable to represent line diagram images. In geometric encoding, the amount of data required to represent or store the line diagram images is proportional to the image detail. Thus a simple line diagram image would require a small amount of data. To study the effect of transmission errors due to mobile channels on the transmitted images, error sources (error files), which represent mobile channels under different conditions, have been produced using channel modelling techniques. Satisfactory models of the mobile channel have been obtained when compared to the field test measurements. Subjective performance tests have been carried out to evaluate the quality and usefulness of the received line diagram images under various mobile channel conditions. The effect of mobile transmission errors on the quality of the received images has been determined. To improve the quality of the received images under various mobile channel conditions, forward error correcting codes (FEC) with interleaving and automatic repeat request (ARQ) schemes have been proposed. The performance of the error control codes have been evaluated under various mobile channel conditions. It has been shown that a FEC code with interleaving can be used effectively to improve the quality of the received images under normal and severe mobile channel conditions. Under normal channel conditions, similar results have been obtained when using ARQ schemes. However, under severe mobile channel conditions, the FEC code with interleaving shows better performance
Advanced models of human skeletal muscle differentiation, development and disease: Three-dimensional cultures, organoids and beyond
Advanced in vitro models of human skeletal muscle tissue are increasingly needed to model complex developmental dynamics and disease mechanisms not recapitulated in animal models or in conventional monolayer cell cultures. There has been impressive progress towards creating such models by using tissue engineering approaches to recapitulate a range of physical and biochemical components of native human skeletal muscle tissue. In this review, we discuss recent studies focussed on developing complex in vitro models of human skeletal muscle beyond monolayer cell cultures, involving skeletal myogenic differentiation from human primary myoblasts or pluripotent stem cells, often in the presence of structural scaffolding support. We conclude with our outlook on the future of advanced skeletal muscle three-dimensional cultures (e.g. organoids and biofabrication) to produce physiologically and clinically relevant platforms for disease modelling and therapy development in musculoskeletal and neuromuscular disorders
Flow Injection Analysis with Turbidity Detection for the Quantitative Determination of Mebeverine Hydrochloride in Pharmaceutical Formulations
كان الهدف الرئيسي من هذه الورقة هو تطوير والتحقق من صحة طريقة حقن التدفق، وهي طريقة دقيقة ودقيقة وبسيطة واقتصادية ومنخفضة التكلفة ومحددة لقياس التعكر من أجل التقدير الكمي لهيدروكلوريد الميفبيرين (MBH) في المستحضرات الصيدلانية. تم أستخدام محلل NAG Dual & Solo محلي الصنع (0-180º درجة) والذي يحتوي على وحدتي اكتشاف متطابقتين (الخلية 1 و2) لقياسات التعكر. تم تحسين الطريقة المطورة من خلال اجراء معاييرات كيميائية وفيزيائية مختلفة مثل تركيزات الكاشف ومحاليل الأملاح المائية ومعدل التدفق وشدة ضوء المصدر وحجم العينة وملف الخلط ووقت الحقن. كانت معاملات الارتباط للطريقة المطورة(r) 0.9980 و0.9986 للخلية 1 و2 على التوالي وأظهرت استجابة خطية ضد التركيز على مدى 1.0 إلى 6.5 و 0.7-6.5 مليمول / لتر للخلية 1 و 2 على التوالي. كان حد الكشف (LOD) للخلية 1 والخلية2 هو 0.28 و0.21 مليمول / لتر على التوالي. أظهرت الدقة خلال اليوم وبين اليوم لتقديرين تسلسليين 3.5 و 5.5 مليمول / لتر من MBH انحرافًا معياريًا نسبيًا قدره 0.46٪ ، 0.28٪ ، 0.23٪ ، 0.26٪ و 0.39٪ ، 0.79٪ ، 0.14٪ ، 0.05 ٪ للخلية 1 و 2 على التوالي. تم التعبير عن دقة الطريقة المطورة كنسبة مئوية للاسترداد (Rec٪) ونسبة خطأ تتراوح بين 99.22 إلى 101.13 و 99.39 إلى 101.17 للخلية 1 والخلية 2 على التوالي. تم اتباع إرشادات ICH للتحقق من صحة الطريقة. تم تطبيق الطريقة التي تم تطويرها بنجاح لتحديد MbH في المستحضرات النقية والصيدلانية ويمكن استخدام الطريقة بشكل ملائم للتحليل الروتيني في المختبر كطريقة لمراقبة الجودة لأن الطريقة تسمح بالتحديد الكمي لـ 60 عينة / ساعة.The main objective of this paper is to develop and validate flow injection method, a precise, accurate, simple, economic, low cost and specific turbidimetric method for the quantitative determination of mebeverine hydrochloride (MbH) in pharmaceutical preparations. A homemade NAG Dual & Solo (0-180º) analyser which contains two identical detections units (cell 1 and 2) was applied for turbidity measurements. The developed method was optimized for different chemical and physical parameters such as perception reagent concentrations, aqueous salts solutions, flow rate, the intensity of the sources light, sample volume, mixing coil and purge time. The correlation coefficients (r) of the developed method were 0.9980 and 0.9986 for cell 1 and 2 respectively and showed the linearity of response against concentration over the range of 1.0 to 6.5 and 0.7-6.5mmol/L for cell 1 & 2 respectively. The limit of detections (LOD) for cell 1 and cell 2 were 0.28 and 0.21 mmol/L respectively. The intra-day and inter-day precision for two serial estimations of 3.5 and 5.5 mmol/L of MBH exhibited a relative standard deviation of 0.46%, 0.28%, 0.23%, 0.26% and 0.39%, 0.79%, 0.14%, 0.05% for cell 1 & 2 respectively. The accuracy of the developed method has expressed a recovery percentage (Rec %) and error % which was between 99.22 to 101.13 and 99.39 to 101.17 for cell 1 and cell 2 respectively. The ICH guidelines were followed for method validation. The developed method was successfully applied for the determination of MbH in pure and pharmaceutical preparations and the method can be conveniently used for routine analysis in laboratory as a quality control method since the method permits quantitively determination of 60 samples/h
Exogenous application of agmatine improves water stress and salinity stress tolerance in turnip (Brassica rapa L.)
This study was carried out to determine the consequence of foliar application of agmatine (0 and 0.5 mM), on growth, physiological and biochemical traits, and yield of turnip (Brassica rapa L.) plants grown under water stress or salt stress conditions. The effect of three irrigation regimes (100%, 80% and 40% of field capacity) and three salt concentrations (0, 100 and 200 mM NaCl) on turnip plants grown in pots under greenhouse conditions were studied. Water deficit developed at 40% Field capacity (FC) and salinity stress, especially at 200 mM, resulted in significant decreases in all growth parameters when compared to control plants (100% FC) including root length and diameter as well as shoot weights per plant. Water stress and high salt stress negatively affected most physiological and biochemical characteristics such as total chlorophyll, photosynthetic rate, stomatal conductance, and transpiration rate. Water use efficiency (WUE) increased under 80% FC or 100 mM NaCl. Antioxidant enzymes activity, catalase and peroxidase and glutathione reductase, increased with water stress and salt stress. Foliar application of agmatine seemed to alleviate the adverse effects of water stress and salt stress on turnip. Alleviating harmful effects of salt stress and enhancing water stress tolerance by agmatine was associated with improving leaf gas exchange, antioxidant enzymes and protein profile
Human Depth Sensors-based Activity Recognition using Spatiotemporal Features and Hidden Markov Model for Smart Environments
116Yscopu
On adaptive wavelet estimation of a class of weighted densities
We investigate the estimation of a weighted density taking the form
, where denotes an unknown density, the associated
distribution function and is a known (non-negative) weight. Such a class
encompasses many examples, including those arising in order statistics or when
is related to the maximum or the minimum of (random or fixed)
independent and identically distributed (\iid) random variables. We here
construct a new adaptive non-parametric estimator for based on a plug-in
approach and the wavelets methodology. For a wide class of models, we prove
that it attains fast rates of convergence under the risk with
(not only for corresponding to the mean integrated squared
error) over Besov balls. The theoretical findings are illustrated through
several simulations
Biodegradation Studies in Vitro of Novel Poly(adipic anhydride-co-mannitol)-N-maleoyl Chitosan Networks
In this work, novel copolymers of poly(adipic anhydride-co-mannitol) were synthesized by melting condensation polymerization of poly(adipic anhydride) with five percentages of mannitol sugar, 1 to 5 Wt.%. These copolymers were purified and then, characterized by FT-IR, which was proved that the cross-linking reaction was caused by nucleophilic attack of mannitol hydroxyl group to acidic anhydride groups of poly(adipic anhydride) backbone and new ester groups were formed and appeared. Also, modified organic-soluble chitosan, N-maleoyl-chitosan, were synthesized by grafting reaction of chitosan with maleic anhydride in DMF as solvent, and it was also purified and characterized by FT-IR. Biodegradation in vitro of the IPNs of poly(adipic anhydride-co-mannitol)-N-maleoyl chitosan networks were evaluated by hydrolytic degradation studies at three different media (PBS, SIF and SGF) for 18 weeks with 92% as maximum degradation and it was found that minimum weight loss of IPNs was noticeably shown in SIF. In addition, hydrolytic degradation percent was decreased with increasing mannitol proportions
Depth Images-based Human Detection, Tracking and Activity Recognition Using Spatiotemporal Features and Modified HMM
Human activity recognition using depth information is an emerging and challenging technology in computer vision due to its considerable attention by many practical applications such as smart home/office system, personal health care and 3D video games. This paper presents a novel framework of 3D human body detection, tracking and recognition from depth video sequences using spatiotemporal features and modified HMM. To detect human silhouette, raw depth data is examined to extract human silhouette by considering spatial continuity and constraints of human motion information. While, frame differentiation is used to track human movements. Features extraction mechanism consists of spatial depth shape features and temporal joints features are used to improve classification performance. Both of'these features are fused together to recognize different activities using the modified hidden Markov model (M-HMM). The proposed approach is evaluated on two challenging depth video datasets. Moreover, our system has significant abilities to handle subject's body parts rotation and body parts missing which provide major contributions in human activity recognition.1165Ysciescopuskc
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