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1.
Compr Rev Food Sci Food Saf ; 23(1): e13286, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38284581

ABSTRACT

Emerging nonthermal and thermal food processing technologies are a better alternative to conventional thermal processing techniques because they offer high-quality, minimally processed food. Texture is important in the food industry because it encompasses several product attributes and plays a vital role in consumer acceptance. Therefore, it is imperative to analyze the extent to which these technologies influence the textural attributes of food grains. Physical forces produced by cavitation are attributed to ultrasound treatment-induced changes in the conformational and structural properties of food proteins. Pulsed electric field treatment causes polarization of starch granules, damaging the dense outer layer of starch granules and decreasing the mechanical strength of starch. Prolonged radio frequency heating results in the denaturation of proteins and gelatinization of starch, thus reducing binding tendency during cooking. Microwave energy induces rapid removal of water from the product surface, resulting in lower bulk density, low shrinkage, and a porous structure. However, evaluating the influence of these techniques on food grain texture is difficult owing to differences in their primary operation mode, operating conditions, and equipment design. To maximize the advantages of nonthermal and thermal technologies, in-depth research should be conducted on their effects on the textural properties of different food grains while ensuring the selection of appropriate operating conditions for each food grain type. This article summarizes all recent developments in these emerging processing technologies for food grains, discusses their potential applications and drawbacks, and presents prospects for future developments in food texture enhancement.


Subject(s)
Food Handling , Food Quality , Food Handling/methods , Cooking , Starch/chemistry , Edible Grain
2.
Sensors (Basel) ; 21(21)2021 Oct 30.
Article in English | MEDLINE | ID: mdl-34770547

ABSTRACT

This paper presents a systematic and efficient design approach for the two degree-of-freedom (2-DoF) capacitive microelectromechanical systems (MEMS) accelerometer by using combined design and analysis of computer experiments (DACE) and Gaussian process (GP) modelling. Multiple output responses of the MEMS accelerometer including natural frequency, proof mass displacement, pull-in voltage, capacitance change, and Brownian noise equivalent acceleration (BNEA) are optimized simultaneously with respect to the geometric design parameters, environmental conditions, and microfabrication process constraints. The sampling design space is created using DACE based Latin hypercube sampling (LHS) technique and corresponding output responses are obtained using multiphysics coupled field electro-thermal-structural interaction based finite element method (FEM) simulations. The metamodels for the individual output responses are obtained using statistical GP analysis. The developed metamodels not only allowed to analyze the effect of individual design parameters on an output response, but to also study the interaction of the design parameters. An objective function, considering the performance requirements of the MEMS accelerometer, is defined and simultaneous multi-objective optimization of the output responses, with respect to the design parameters, is carried out by using a combined gradient descent algorithm and desirability function approach. The accuracy of the optimization prediction is validated using FEM simulations. The behavioral model of the final optimized MEMS accelerometer design is integrated with the readout electronics in the simulation environment and voltage sensitivity is obtained. The results show that the combined DACE and GP based design methodology can be an efficient technique for the design space exploration and optimization of multiphysics MEMS devices at the design phase of their development cycle.


Subject(s)
Micro-Electrical-Mechanical Systems , Acceleration , Computer Simulation , Computers , Normal Distribution
3.
Rev Sci Instrum ; 92(10): 105007, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34717427

ABSTRACT

This paper presents experimental force and buckling analysis of a compliant micro-displacement amplification mechanism fabricated using the commercially available PolyMUMPs process. The proposed mechanism proficiently amplifies displacement, at two output ends, with an optimal amplification factor of 7.2. Buckling analysis revealed that an amplification factor ranging from 2.8 to 11 may be achieved for an input displacement varying from 0.1 to 7.5 µm. Based on the analysis, the optimal value of the amplification factor is found to be 7.2 with an input displacement of 3.5 µm at the operational force of 60 µN having a buckling load factor (BLF) >1. Critical load magnitude is 187 µN having BLF = 1. Buckling occurred when loading exceeded the critical load value, having BLF <1, and the mechanism failed to produce a significant amplification factor. Static analysis showed that stresses produced are within the safe region, and the structural integrity of the mechanism is not compromised having a factor of safety of 1.4. Modal analysis predicted that the natural frequency of the desired mode is 35.47 kHz. Dynamic simulations, under 15 g dynamic load with a frequency range of 30-40 kHz, confirm the possibility of integrating the proposed mechanism with MEMS devices. Parametric optimization comprehends that length and angle are the two major geometric parameters that govern the working range, force, and amplification factor. For input displacements below 1 µm, the amplification factor is even higher, which is highly beneficial for amplifying small displacements. Static, modal, and dynamic analyses of the designed mechanism have been carried out using finite element method based commercial software IntelliSuite®. The experimental results showed that this mechanism can provide the same amplified displacement at two output points and is self-sufficient to be incorporated as an intermediate compliant mechanism for enhancing the output in the case of both static and dynamic micro-devices.

4.
Rev Sci Instrum ; 92(4): 045007, 2021 Apr 01.
Article in English | MEDLINE | ID: mdl-34243476

ABSTRACT

This research paper presents design and analysis of the multi-jaw microgripper that can manipulate microbiological organisms and species, cell probing and measurement, biomedical sample sorting, and preparation. Four jaws, actuated with a single thermal chevron actuator, can grip microbiological species ranging from 300 to 700 µm, 1 to 340 µm, 100 µm pool, and 1 to 120 µm spongy cells, respectively. Jaws are designed in such a way that they can grip regular, irregular, and spongy shaped biological species and their organelles. Parametric analysis of the microgripper exhibited that at 10 V, the efficiency of the thermal actuator is at maximum with respect to displacement, force, and temperature. To enhance displacement to voltage ratio and increase the energy efficiency, a class 3 lever mechanism has been incorporated. The amplification factors at four jaws are 17.21, 13.82, 4.02, and 4.93, respectively. For controlled application of the force to microspecies, two electrostatic force sensors have been amalgamated with jaws having capacitive sensitivities of 1.59 nf/µm, 1.91 nf/µm, 17 nf/µm, and 14.5 nf/µm, respectively. Electrothermal, static, and electrostatic analyses have been carried out with the finite element methods based software IntelliSuite®. Stress magnitudes are within the limits of structural integrity of silicon having a factor of safety 2.5. Thermal analysis revealed that at a differential voltage of 10 V, the maximum temperature goes up to 425 °C. Buckling analysis results depicted that the critical load for the thermal actuator is 241 µN with the buckling load factor greater than unity. This paper focuses on microbiological applications only; however, the designed microgripper can be used to manipulate micro-objects, microstructures, microelectronics parts, and micro assembly.


Subject(s)
Mechanical Phenomena , Silicon , Jaw , Static Electricity , Temperature
5.
Eur Heart J Case Rep ; 5(2): ytaa263, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33738394

ABSTRACT

BACKGROUND: Management of cardiovascular sequelae to Kawasaki disease (KD) is challenging to adult cardiologists. Vasculitis of medium-sized arteries especially coronary arteries often leads to focal intimal thickening and aneurysmal dilatation of one or more coronary arteries. It needs special attention to recognize coronary artery involvement because of potential long-term morbidity and mortality. We present a case of diagnostic dilemma in young adult Chinese male with KD. CASE SUMMARY: This asymptomatic patient was found to have deep Q waves in anterior leads on screening electrocardiography and was thought to have myocarditis after depiction of wall motion abnormality on echocardiography, later to be confirmed to have left anterior descending artery (LAD) territory infarct on cardiac magnetic resonance imaging. Coronary computed tomography angiogram depicted proximal LAD aneurysm with calcified plaque/thrombus. Additionally, there was an 18 mm giant right coronary artery (RCA) aneurysm with braid-like appearance and soft plaque (mural thrombus). His previous medical history included fever and cervical lymphadenopathy. Because of the high risk he was commenced on long-term low-dose aspirin and ß-adrenergic-blocking agent to reduce myocardial oxygen consumption; however, 3 years later, he presented to the emergency department with acute inferior myocardial infarction. He was noted to have total occlusion of the proximal RCA and was treated aggressively with thrombectomy and percutaneous balloon angioplasty followed by medical management with ß-blockers, sacubitril/valsartan, clopidogrel, and rivaroxaban without subsequent adverse cardiovascular events. DISCUSSION: Kawasaki disease is one of the main causes of coronary artery disease in young adults and can be easily overlooked.

6.
Adv Differ Equ ; 2020(1): 675, 2020.
Article in English | MEDLINE | ID: mdl-33281894

ABSTRACT

A disastrous coronavirus, which infects a normal person through droplets of infected person, has a route that is usually by mouth, eyes, nose or hands. These contact routes make it very dangerous as no one can get rid of it. The significant factor of increasing trend in COVID19 cases is the crowding factor, which we named "crowding effects". Modeling of this effect is highly necessary as it will help to predict the possible impact on the overall population. The nonlinear incidence rate is the best approach to modeling this effect. At the first step, the model is formulated by using a nonlinear incidence rate with inclusion of the crowding effect, then its positivity and proposed boundedness will be addressed leading to model dynamics using the reproductive number. Then to get the graphical results a nonstandard finite difference (NSFD) scheme and fourth order Runge-Kutta (RK4) method are applied.

7.
Eur Heart J Case Rep ; 3(2)2019 Jun 01.
Article in English | MEDLINE | ID: mdl-31449631

ABSTRACT

BACKGROUND: Right ventricular diverticula (RVD) are very rare congenital anomalies and their association with constrictive pericarditis is even rarer. So far, only one case has been published in literature. CASE SUMMARY: We report a case of multiple congenital RVD with constrictive pericarditis and right heart failure which was incidentally identified on surveillance computed tomography (CT) for abdominal lymphangioma. Interval CT, echocardiography, and cardiac magnetic resonance imaging (CMR) studies were performed and reviewed. Computed tomography abdomen showed hepatic congestion with features of portal hypertension, increasing size of the RVD on review of serial CTs, and eccentric foci of pericardial calcification. Echocardiography performed for breathlessness demonstrated supranormal early diastolic tissue velocities with average of 19.8 cms-1 and a septal bounce phenomenon on m-mode imaging suggesting constrictive physiology, which triggered a CMR referral. Cardiac magnetic resonance imaging HASTE and right ventricular (RV) outflow tract imaging showed four outpouchings along RV free wall, the largest measuring 4.5 × 2 cm with a sizeable neck. These outpouchings displayed a trabecular network and/or were contractile aiding the diagnosis of diverticula as opposed to aneurysms. Right ventricular function was moderately compromised, whereas left ventricular function was preserved. DISCUSSION: Right ventricular diverticula can be associated with, and potentially be causative of, pericardial thickening and calcification eventually leading to constrictive pericarditis and heart failure.

8.
Sensors (Basel) ; 18(9)2018 Aug 25.
Article in English | MEDLINE | ID: mdl-30149631

ABSTRACT

Energy consumption in the residential sector is 25% of all the sectors. The advent of smart appliances and intelligent sensors have increased the realization of home energy management systems. Acquiring balance between energy consumption and user comfort is in the spotlight when the performance of the smart home is evaluated. Appliances of heating, ventilation and air conditioning constitute up to 64% of energy consumption in residential buildings. A number of research works have shown that fuzzy logic system integrated with other techniques is used with the main objective of energy consumption minimization. However, user comfort is often sacrificed in these techniques. In this paper, we have proposed a Fuzzy Inference System (FIS) that uses humidity as an additional input parameter in order to maintain the thermostat set-points according to user comfort. Additionally, we have used indoor room temperature variation as a feedback to proposed FIS in order to get the better energy consumption. As the number of rules increase, the task of defining them in FIS becomes time consuming and eventually increases the chance of manual errors. We have also proposed the automatic rule base generation using the combinatorial method. The proposed techniques are evaluated using Mamdani FIS and Sugeno FIS. The proposed method provides a flexible and energy efficient decision-making system that maintains the user thermal comfort with the help of intelligent sensors. The proposed FIS system requires less memory and low processing power along with the use of sensors, making it possible to be used in the IoT operating system e.g., RIOT. Simulation results validate that the proposed technique reduces energy consumption by 28%.

9.
Cancer Manag Res ; 10: 1619-1626, 2018.
Article in English | MEDLINE | ID: mdl-29950899

ABSTRACT

The decreased bone mineral density and compromised bone strength predispose individuals to skeletal osteoporosis. Both prostate cancer and bone metastasis caused by cancer invasion have remained a great challenge to researchers. With the advancement in the fields of biochemistry and biomechanics, the molecular mechanisms that make prostate cancer metastasize to bone have recently been identified, and they provide new molecular targets for drug development. Many biochemical by-products have been identified to help in understanding the interaction between the bone and the tumor. Enhanced clinical management of patients with bone metastases was reported during the past decade; however, the anticipated risk and the response to the therapy are still challenging to assess. In this review, the key players that play a dominant role in secondary osteoporosis are addressed. An attempt is made to provide the readers with a clear understanding of the communication pathways between each of the cell types involved in this vicious cycle. Furthermore, the role of Wnts, sclerostin, RANKL, PTHrP, and their respective clinical studies are addressed in this study.

10.
J Pak Med Assoc ; 67(9): 1404-1409, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28924283

ABSTRACT

Due to their numerous advantages, laparoscopic surgical procedures are increasingly becoming common in the operation theatres over the past few decades. Virtual reality training simulators have played a significant role during this transition from traditional to laparoscopic procedures by enhancing surgical skills, such as hand-eye coordination in laparoscopy, and practising surgical scenarios that cannot be easily created using physical models. This paper presents a general framework for such a training simulator while identifying its key components and their specific roles in enhancing various laparoscopic skills. The paper also describes a laparoscopic simulator, developed in our lab, based on the proposed framework. The results are promising and open new doors for research and development.


Subject(s)
Laparoscopy/education , Robotic Surgical Procedures/education , Simulation Training , Virtual Reality , Humans , User-Computer Interface
11.
Surg J (N Y) ; 3(4): e145-e147, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28924614

ABSTRACT

Background Porcelain gallbladder (GB) is a rare but potentially premalignant condition with minimal symptoms. Accident and Emergency (A&E) departments often tend to investigate abdominal pain through plain radiographs, which are occasionally reported by radiologists, thereby leaving behind few uncommon conditions, such as porcelain gallbladder unreported. Objectives We present three cases of porcelain GB in which initial diagnosis was not considered due to the presence of various other calcifications in the upper abdomen. Methods In A&E, plain abdominal X-rays were routinely performed in all three patients to investigate nonspecific postprandial abdominal pain. Although GB calcification was easy to diagnose on plain films, it was initially overlooked to be a cause of the symptoms and later was diagnosed on abdominal CT scans, performed for further evaluation. Results Abdominal X-rays revealed thin curvilinear calcification in the GB wall, partially calcified neck and body, and gall stones. CT scan confirmed porcelain GB in all three patients. Conclusion Gallbladder mural calcification is a rare cause of nonspecific abdominal pain, which is often overlooked on plain abdominal X-rays causing missed diagnosis. The association of porcelain GB with adenocarcinoma entails special emphasis on timely diagnosis and prompt management.

12.
J Ayub Med Coll Abbottabad ; 29(1): 83-86, 2017.
Article in English | MEDLINE | ID: mdl-28712181

ABSTRACT

BACKGROUND: Extra virgin olive oil (EVOO) is fruit oil with rich source of monounsaturated fats and powerful antioxidants. It acts as hypolipidemic agent and significant decrease of plasma lipids level was observed with EVOO use. Atorvastatin is hypolipidemic drug commonly used for treatment of hyperlipidaemia. The purpose of this study was to determine & compare the lipid lowering effect of EVOO with atorvastatin in type 2 diabetic dyslipidaemia which is leading cause of microvascular diseases. METHODS: This randomised controlled trial was conducted on 60 already diagnosed cases of type 2 diabetes mellitus with dyslipidaemia. All sixty subjects were divided randomly into 2 groups. Atorvastatin 40 mg was given to Group One and two tablespoons of extra virgin olive oil orally per day was given to Group Two. Blood was collected for estimation of plasma lipids level at base line, 4th week, and 6th weeks in two groups and was compared statistically. RESULTS: The present study demonstrated 20-40% lipid lowering effect of atorvastatin on plasma lipids level with 9-16% increase in HDL while extra virgin olive oil showed 14-25% reduction in plasma lipids with 8-12% increase in HDL-cholesterol level. CONCLUSIONS: This study concludes that both atorvastatin and extra virgin olive oil are effective in reducing plasma lipids level in type 2 diabetic dyslipidaemia with more prominent effect of atorvastatin than EVOO.


Subject(s)
Atorvastatin/therapeutic use , Diabetes Mellitus, Type 2/complications , Hyperlipidemias , Hypolipidemic Agents/therapeutic use , Lipids/blood , Olive Oil/therapeutic use , Humans , Hyperlipidemias/blood , Hyperlipidemias/diet therapy , Hyperlipidemias/drug therapy
14.
Oncogene ; 21(34): 5255-67, 2002 Aug 08.
Article in English | MEDLINE | ID: mdl-12149647

ABSTRACT

Spectrins play a pivotal role in axonal transport, neurite extension, the organization of synaptic vesicles, as well as for protein sorting in the Golgi apparatus and cell membrane. Among spectrins there is great variability in sequence composition, tissue distribution, and function, with two known genes encoding the alpha-chain, and at least five encoding the beta-chain. It remains unclear as to whether novel beta-spectrins such as elf1-4 are distinct genes or beta-G-spectrin isoforms. The role for ELF in the developing nervous system has not been identified to date. In this study we demonstrate the genomic structure of elf-3, as well as the expression of ELF in the developing mouse brain using a peptide specific antibody against its distinctive amino-terminal end. Full genomic structural analyses reveal that elf-3 is composed of 31 exons spanning approximately 67 kb, and confirm that elf and mouse brain beta-G-spectrin share multiple exons, with a complex form of exon/intron usage. In embryonic stages, E9-12, anti-ELF localized to the primary brain vesicular cells that also labeled strongly with anti-nestin but not anti-vimentin. At E12-14, anti-ELF localized to axonal sprouts in the developing neuroblasts of cortex and purkinje cell layer of the cerebellum, as well as in cell bodies in the diencephalon and metencephalon. Double labeling identified significant co-localization of anti-ELF, nestin and dystrophin in sub ventricular zone cells and in stellate-like cells of the developing forebrain. These studies define clearly the expression of ELF, a new isoform of beta-G-spectrin in the developing brain. Based on its expression pattern, ELF may have a role in neural stem cell development and is a marker of axonal sprouting in mid stages of embryonic development.


Subject(s)
Brain/embryology , Caenorhabditis elegans Proteins , DNA-Binding Proteins , Neurons/metabolism , Proto-Oncogene Proteins/genetics , Spectrin/metabolism , Transcription Factors/genetics , Alternative Splicing , Animals , Ankyrins/metabolism , Base Sequence , Biomarkers , Blotting, Western , Brain/cytology , Brain/metabolism , Cell Division , Cloning, Molecular , Dystrophin/metabolism , Exons , Immunoenzyme Techniques , Immunoglobulin G/immunology , Introns , Mice , Molecular Sequence Data , Promoter Regions, Genetic , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins c-ets , Transcription Factors/metabolism
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