Ahsan A.,University Putra Malaysia |
Ahsan A.,Institute of Advanced Technology |
Imteaz M.,Swinburne University of Technology |
Dev R.,Motilal Nehru National Institute of Technology |
Arafat H.A.,Masdar Institute of Science and Technology
Desalination | Year: 2013
In this paper, a detailed comparison of a few numerical models (with and without considering humid air properties) for the estimation of water production from a solar water distillation device is investigated. An extensive laboratory production experiments were executed under fifteen sets of external conditions to find the properties of evaporation and condensation coefficients to incorporate with the present evaporation and condensation models (two unique and independent theoretical models), respectively. The calculation accuracy of the evaporation flux computed by two evaporation models (present and previous), Dunkle's and Ueda's model, and of the hourly condensation flux estimated by two condensation models (present and previous) was examined using the field experimental results. It was found that the previous evaporation and condensation models using empirical relationships extremely overestimated and underestimated the observed production flux, respectively. The evaporation flux calculated by the conventional models of Dunkle and Ueda notably underestimated and overestimated the observed values, respectively. Finally, it is revealed that the present models have the smallest deviation between the calculated and the observed values among these six models and can predict the daily production flux. © 2012 Elsevier B.V.
Pradhan B.,Institute of Advanced Technology
Applied Mechanics and Materials | Year: 2012
The escalating number of occurrences of natural hazards such as landslides has raised a great interest among the geoscientists. Due to the extremely high number of point's returns, airborne LiDAR permits the formation of more accurate DEM compared to other space borne and airborne remote sensing techniques. This study aims to assess the capability of LiDAR derived parameters in landslide susceptibility mapping. Due to frequent occurrence of landslides, Ulu Klang in Selangor state in Malaysia has been considered as application site. A high resolution of airborne LiDAR DEM was constructed to produce topographic attributes such as slope, curvature and aspect. These data were utilized to derive secondary deliverables of landslide parameters such as topographic wetness index (TWI), surface area ratio (SAR) and stream power index (SPI). A probabilistic based frequency ratio model was applied to establish the spatial relationship between the landslide locations and each landslide related factors. Subsequently, factor ratings were summed up to yield Landslide Susceptibility Index (LSI) and finally a landslide susceptibility map was prepared. To test the model performance, receiver operating characteristics (ROC) curve was carried out together with area under curve (AUC) analysis. The produced landslide susceptibility map demonstrated that high resolution airborne LiDAR data has huge potential in landslide susceptibility mapping. © (2012) Trans Tech Publications, Switzerland.
Pradhan B.,Institute of Advanced Technology
Proceedings - 2012 IEEE 8th International Colloquium on Signal Processing and Its Applications, CSPA 2012 | Year: 2012
Landslides are one of the most important natural hazards which have been a major focus of investigation for international community. The consequences from its occurrences are highly contributed to enormous damages and economical losses in Malaysia. This has been recognized by many professional authorities and has led to a number of landslide hazard and risk mapping both in qualitative and quantitative ways. In this research, LiDAR data was used to generate landslide geomorphological surface. The landslide conditioning factors considered for the study area were slope gradient, curvature, topographic wetness index and soil type. The correlation of each parameter with landslide occurrences was then measured by using probabilistic based frequency ratio method and landslide susceptibility map was produced. The landslide susceptibility map can be very useful for general landuse planning © 2012 IEEE.
Kassim M.S.M.,Institute of Advanced Technology |
Ramli A.R.,University Putra Malaysia
Journal of Food, Agriculture and Environment | Year: 2012
Oil palm fresh fruit bunches (FFB) need to be harvested at the optimum maturity stage to optimise the quality of palm oil. Currently the oil palm harvester manually determines the FFB maturity based natural indicators such as FFB color appearance and number of FFB loose fruit drops under the tree. During executing the harvesting operation the harvester need to search for a ripe FFB and at the same time carrying the harvesting pole. Tedious harvesting operation degrades the consistency of their judgment. The harvested FFB must be screened at the oil palm mill to separate into groups of maturity level according to the standard. A computer application called Maturity Table was developed to manage the FFB maturity information in form of digital images. The development of FFB from the anthesis to harvesting stage was monitored by using a handy digital camera. The digital images of the FFB were processed by using digital image processing techniques to extract the color that represent the maturity stages. As a result from the analysed image information and tabulated data in Maturity Table, a relationship of FFB color changing and maturity stages were investigated. The processed information also enables the development of a map displaying the location of FFB and the maturity stages. The developed map can be used as a support system in harvesting operation. This support system enables site specific harvesting at optimum maturity stage, overcome losses due uncollected loose fruit, potential application to eliminate FFB screening process at oil palm mill level and potential tool to predict FFB yield as well as plantation resources management.
Salavert J.,Capio Hospital General Of Catalonia |
Salavert J.,University of Barcelona |
Gasol M.,Capio Hospital General Of Catalonia |
Vieta E.,University of Barcelona |
And 4 more authors.
Journal of Affective Disorders | Year: 2011
Introduction: Several functional neuroimaging studies have demonstrated abnormalities in fronto-limbic pathways when comparing borderline personality disorder (BPD) patients with controls. The present study aimed to evaluate regional cerebral metabolism in euthymic BPD patients with similar measured impulsivity levels by means of 18F-FDG PET during resting state and to compare them against a control group. Methods: The present study evaluates regional cerebral metabolism in 8 euthymic BPD patients with 18F-FDG PET during resting state as compared to 8 controls with similar socio-geographic characteristics. Results: BPD patients presented a marked hypo-metabolism in frontal lobe and showed hyper-metabolism in motor cortex (paracentral lobules and post-central cortex), medial and anterior cingulus, occipital lobe, temporal pole, left superior parietal gyrus and right superior frontal gyrus. No significant differences appeared in basal ganglia or thalamus. Conclusions: Results reveal a dysfunction in patients' frontolimbic network during rest and provide further evidence for the importance of these regions in relation to BPD symptomatology. © 2011 Elsevier B.V. All rights reserved.
News Article | April 20, 2016
An hour's drive from Kunming in southwestern China, past red clay embankments and sprawling forests, lies an unusual zoo. Inside the gated compound is a quiet, idyllic campus; a series of grey, cement animal houses stack up on the lush hillside, each with a clear plastic roof to let in the light. This is the Yunnan Key Laboratory of Primate Biomedical Research, and its inhabitants are some 1,500 monkeys, all bred for research. The serenity of the facility belies the bustle of activity within. Since it opened in 2011, this place has quickly become a Mecca for cutting-edge primate research, producing valuable disease models and seminal publications that have made its director, Ji Weizhi, a sought-after collaborator. Its campus houses a collection of gene-edited monkeys that serve as models of Duchenne muscular dystrophy, autism and Parkinson's disease. Ji plans to double the number of group leaders working there from 10 to 20 in the next 3 years, and to seek more international collaborations — he already works with scientists in Europe and the United States. “In terms of a technology platform, Ji is just way ahead,” says one collaborator, cardiologist Kenneth Chien at the Karolinska Institute in Stockholm. Ji is not alone in his ambitions for monkey research. With support from central and local governments, high-tech primate facilities have sprung up in Shenzhen, Hangzhou, Suzhou and Guangzhou over the past decade. Last month, the science ministry approved the launch of a facility at the Kunming Institute of Zoology that is expected to cost millions of dollars to build. These centres can provide scientists with monkeys in large numbers, and offer high-quality animal care and cutting-edge equipment with little red tape. A major brain project, expected to be announced in China soon, will focus much of its efforts on using monkeys to study disease. The enthusiasm stands in stark contrast to the climate in the West, where non-human-primate research is increasingly stymied by a tangle of regulatory hurdles, financial constraints and bioethical opposition. Between 2008 and 2011, the number of monkeys used in research in Europe declined by 28%, and some researchers have stopped trying to do such work in the West. Many have since sought refuge for their experiments in China by securing collaborators or setting up their own laboratories there. Some of the Chinese centres are even advertising themselves as primate-research hubs where scientists can fly in to take advantage of the latest tools, such as gene editing and advanced imaging. “It could be like CERN in Switzerland, where they set up a large facility and then people come from all over the world to get data,” says Stefan Treue, a neuroscientist who heads the German Primate Center in Göttingen, Germany. With China fast becoming a global centre for primate research, some scientists fear that it could hasten the atrophy of such science in the West and lead to a near monopoly, in which researchers become over-reliant on one country for essential disease research and drug testing. “Governments and politicians don't see this, but we face a huge risk,” says Erwan Bezard, who is director of the Institute of Neurodegenerative Diseases at the University of Bordeaux in France, and has set up his own primate-research company, Motac, in Beijing. Europe and the United States still have the lead in primate research, he says, but this could change as expertise migrates eastwards. “China will become the place where all therapeutic strategies will have to be validated. Do we want that? Or do we want to stay in control?” For decades, researchers have relied on monkeys to shed light on brain function and brain disease because of their similarity to humans. Growth in neuroscience research has increased demand, and although high costs and long reproductive cycles have limited the use of these animals in the past, new reproductive technologies and genetic-engineering techniques such as CRISPR–Cas9 are helping researchers to overcome these drawbacks, making monkeys a more efficient experimental tool. China has an abundance of macaques — the mainstay of non-human-primate scientific research. Although the population of wild rhesus macaques (Macaca mulatta) has declined, the number of farmed animals has risen. According to data from the Chinese State Forestry Administration, the number of businesses breeding macaques for laboratory use rose from 10 to 34 between 2004 and 2013, and the quota of animals that those companies could sell in China or overseas jumped from 9,868 to 35,385 over that time. Farm populations of marmosets, another popular research animal, are also on the rise. Most monkeys are shipped to pharmaceutical companies or researchers elsewhere in the world, but the growing appreciation among scientists of monkey models has prompted investment by local governments and private companies in dedicated research colonies. The country's 2011 five-year plan singled out primate disease models as a national goal; the science ministry followed up by pumping 25 million yuan (US$3.9 million) into the endeavour in 2014. Scientists visiting China are generally pleased with the care given to animals in these facilities, most of which have, or are trying to get, the gold-standard recognition of animal care — accreditation by AAALAC International. Ji's Yunnan Key Laboratory is the most active primate facility, but others are giving it competition. The new monkey facility at the Kunming Institute of Zoology was funded as part of the national development scheme for big science equipment that includes telescopes and supercomputers. The money will help the institute to double its colony of 2,500 cynomolgus monkeys (Macaca fascicularis) and rhesus macaques. Zhao Xudong, who runs the primate-research facility, says that the plan is to “set it up like a hospital, with separate departments for surgery, genetics and imaging”, and a conveyer belt to move monkeys between departments. There will be systems for measuring body temperature, heart rate and other physiological data, all to analyse the characteristics, or 'phenotypes', of animals, many of which will have had genes altered. “We are calling it the 'genotype versus phenotype analyser',” says Zhao. It will take ten years to finish, but he hopes to begin building this year and to start research within three. Other facilities, although smaller, are also expanding and diversifying. The Institute of Neuroscience in Shanghai plans to increase its population of 600 Old World monkeys to 800 next year and expand its 300-strong marmoset colony. Outside China, the numbers are heading in the opposite direction. Harvard Medical School closed its affiliated primate facility in May 2015 for 'strategic' reasons. Last December, the US National Institutes of Health decided to phase out non-human-primate experiments at one of its labs and subsequently announced that it would review all non-human-primate research that it funds. In Europe, researchers say, the climate is also growing colder for such research. Costs are a major disincentive. In 2008, Li Xiao-Jiang, a geneticist at Emory University in Atlanta, Georgia, helped to create the world's first transgenic monkey model of Huntington's disease1 with colleagues at Yerkes National Primate Research Centre. But Li says that it costs $6,000 to buy a monkey in the United States, and $20 per day to keep it, whereas the corresponding figures in China are $1,000 and $5 per day. “Because the cost is higher, you have to write a bigger grant, and then the bar will be higher when they judge it,” says Li. Funding agencies “really do not encourage large-animal research”. For Li, the solution was simple: go to China. He now has a joint position at the Institute of Genetics and Developmental Biology in Beijing, where he has access to around 3,000 cynomolgus monkeys at a farm in Guangzhou and some 400 rhesus monkeys at the Chinese Academy of Medical Sciences' monkey facility in Beijing. He has churned out a series of publications on monkeys with modified versions of the genes involved in Duchenne muscular dystrophy2 and Parkinson's disease3. Neuroscientist Anna Wang Roe says that red tape drove her to China. Roe's team at Vanderbilt University in Nashville, Tennessee, is attempting to work out how modules in the brain are connected, and she estimates that she and her colleagues have spent 25% of their time and a good deal of cash documenting the dosage and delivery-method for each drug they administered to their monkeys, as required by regulations. “We record something every 15 minutes,” she says. “It's not that it's wrong. It's just enormously time-consuming.” In 2013, impressed by the collaborative atmosphere at Zhejiang University in Hangzhou, she proposed that it build a neuroscience institute. The next day the university agreed, and she soon had a $25-million, 5-year budget. “Once the decision is made, you can start writing cheques,” she says. She is now closing her US laboratory to be the director of the Zhejiang Interdisciplinary Institute of Neuroscience and Technology, where she hopes to open a suite of the latest brain-analysis tools, including a powerful new 7-tesla functional magnetic resonance imaging device that she says will give images of the primate brain at unprecedented resolution. Bob Desimone was similarly impressed with the speed at which China moves. As a neuroscientist who heads the McGovern Institute for Brain Research at the Massachusetts Institute of Technology in Cambridge, in January 2014, he had a 'meet and greet' with the mayor of Shenzhen. In March, the mayor donated a building on the Shenzhen Institute of Advanced Technology campus for a monkey-research facility, and the centre's soon-to-be director, Liping Wang, promised that it would be ready by summer. Thinking that impossible, Desimone bet two bottles of China's prized mind-numbing liquor, maotai, that it wouldn't be done in time. He lost. The group raised most of the $10 million needed from city development grants, along with a small input from McGovern, and soon the first animals were being installed in the Brain Cognition and Brain Disorder Research Institute. “This place just makes things happen quickly,” Desimone says. But money and monkeys alone are not enough to lead to discovery. Researchers say that China is short on talented scientists to take advantage of the opportunities provided by animal research. That's why the organizers of the country's new primate centres hope to attract an influx of foreigners to permanent posts or as collaborators. So far, many of those moving to China have been Chinese or foreigners with a previous connection to the country, but others are expressing interest, says neuroscientist Guoping Feng, also at the McGovern Institute. Already, the Shenzhen primate centre has recruited from Europe and the United States, and Desimone says that it will be “an open technology base. Anyone who wants to work with monkeys can come.” The rapid spread of CRISPR–Cas9 and TALEN gene-editing tools is likely to accelerate demand for monkey research: they are turning the genetic modification of monkeys from a laborious and expensive task into a relatively quick, straightforward one. Unlike engineered mice, which can be bred and sent around the world, “monkeys are difficult to send, so it will be easier for the PI or postdoc to go there”, says Treue. Already, competition is fierce as researchers are racing for the low-hanging fruit — engineering genes with established roles in human disease or development. Almost all reports of gene-edited monkeys produced with these techniques have come from China. Desimone predicts that the pursuit of monkey disease models “could give China a unique niche to occupy in neuroscience”. The cages of Ji's facility are already full of the products of gene editing. One troop of animals has had a mutation genetically engineered into the MECP2 gene, which has been identified as the culprit in humans with Rett's syndrome, an autism spectrum disorder. An animal sits listless and unresponsive, holding tight to the bars of the cage as her normal twin sister crawls all over her. In another cage, a monkey with the mutation pumps its arm, reminiscent of repetitive behaviour seen in the human disorder. Some incessantly suck their thumbs. “I've never seen that in a monkey before — never so constant,” says Ji. Among the range of other disease models in Ji's menagerie are monkey versions of cardiovascular disease, which he is working on in collaboration with the Karolinska Institute. And last year, Ji made the world's first chimeric monkeys using embryonic stem cells4, an advance that could make the production of genetically modified animals even easier. The question now is whether these genetically modified monkeys will propel understanding of human brain function and dysfunction to a higher level. “You can't just knock out one gene and be sure you'll have human-like disease phenotype,” says Ji. Researchers see an opportunity to understand human evolution as well as disease. Su Bing, a geneticist at the Kunming Institute of Zoology, is working with Ji to engineer monkeys that carry the human version of a gene called SRGAP2, which is thought to endow the human brain with processing power by allowing the growth of connections between neurons. Su also plans to use CRISPR–Cas9 to introduce human versions of MCPH1, a gene related to brain size, and the human FOXP2 gene, which is thought to give humans unique language ability. “I don't think the monkey will all of a sudden start speaking, but will have some behavioural change,” predicts Su. Although the opportunities are great, there are still obstacles for scientists who choose to locate their animal research in China. Trying to keep a foot in two places can be challenging, says Grégoire Courtine, a spinal-cord-injury researcher based at the Swiss Federal Institute of Technology in Lausanne, who travels almost monthly to China to pursue his monkey research at Motac. He has even flown to Beijing, done a couple of operations on his experimental monkeys, then returned that night. “I'm 40 years old, I have energy in my body. But you need to really will it,” he says. Another downside, says Li, is that policies can change suddenly in China. “There is uncertainty. That makes us hesitate to commit,” says Li, who has retained his post at Emory University. And the immunity that China's primate researchers have had to animal-rights activism could start to erode, warns Deborah Cao, who researches law at Griffith University in Brisbane, Australia, and last year published a book on the use of animals in China5. People are starting to use Chinese social-media sites to voice outrage at the abuse of animals, Cao says. China has competition in its bid to dominate primate research, too. Japan has launched its own brain project focused on the marmoset as a model: the animal reaches sexual maturity in a year and a half, less than half the time it takes a macaque. Some research facilities in China are now building marmoset research colonies — but Japan is considered to be several years ahead. And some researchers want to ensure that such work continues outside Asia. Courtine says that he's “fighting to keep alive” a monkey-research programme he has at Fribourg, Switzerland, because he thinks it's important to have a division of labour. “Research that requires quantity, I'll do in China. I would like to do sophisticated work in Fribourg,” he says. Back at his primate centre in Yunnan, Ji is sure that such work is already taking place. His dream, he says is “to have an animal like a tool” for biomedical discovery. He knows there is a lot of competition in this field, especially in China. But he feels confident: “The field is wide, and there are many, many projects we can do.”
Hussein-Al-Ali S.H.,Laboratory of Molecular Biomedicine |
El Zowalaty M.E.,Bioscience Vaccines |
El Zowalaty M.E.,Jazan University |
Hussein M.Z.,Institute of Advanced Technology |
And 5 more authors.
International Journal of Nanomedicine | Year: 2014
Iron oxide magnetic nanoparticles (MNPs) were synthesized by the coprecipitation of iron salts in sodium hydroxide followed by coating separately with chitosan (CS) and polyethylene glycol (PEG) to form CS-MNPs and PEG-MNPs nanoparticles, respectively. They were then loaded with kojic acid (KA), a pharmacologically bioactive natural compound, to form KA-CS-MNPs and KA-PEG-MNPs nanocomposites, respectively. The MNPs and their nanocomposites were characterized using powder X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, vibrating sample magnetometry, and scanning electron microscopy. The powder X-ray diffraction data suggest that all formulations consisted of highly crystalline, pure magnetite Fe3O4. The Fourier transform infrared spectroscopy and thermogravimetric analysis confirmed the presence of both polymers and KA in the nanocomposites. Magnetization curves showed that both nanocomposites (KA-CS-MNPs and KA-PEG-MNPs) were superparamagnetic with saturation magnetizations of 8.1 emu/g and 26.4 emu/g, respectively. The KA drug loading was estimated using ultraviolet-visible spectroscopy, which gave a loading of 12.2% and 8.3% for the KA-CS-MNPs and KA-PEG-MNPs nanocomposites, respectively. The release profile of the KA from the nanocomposites followed a pseudo second-order kinetic model. The agar diffusion test was performed to evaluate the antimicrobial activity for both KA-CS-MNPs and KA-PEG-MNPs nanocomposites against a number of microorganisms using two Gram-positive (methicillin-resistant Staphylococcus aureus and Bacillus subtilis) and one Gram-negative (Salmonella enterica) species, and showed some antibacterial activity, which could be enhanced in future studies by optimizing drug loading. This study provided evidence for the promise for the further investigation of the possible beneficial biological activities of KA and both KA-CS-MNPs and KA-PEG-MNPs nanocomposites in nanopharmaceutical applications. © 2014 Hussein-Al-Ali et al.
Naseri M.G.,University Putra Malaysia |
Naseri M.G.,University of Malayer |
Saion E.B.,University Putra Malaysia |
Hashim M.,University Putra Malaysia |
And 3 more authors.
Solid State Communications | Year: 2011
Crystalline zinc ferrite (ZnFe2O4) was prepared by the thermal treatment method, followed by calcination at various temperatures from 723 to 873 K. Poly (vinyl pyrrolidon) (PVP) was used as a capping agent to stabilize the particles and prevent them from agglomeration. The characterization studies were conducted by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The average particle sizes of 1731 nm were obtained by TEM images, which were in good agreement with the XRD results. Fourier transform infrared spectroscopy (FT-IR) confirmed the presence of metal oxide bands at all temperatures and the absence of organic bands at 873 K. The magnetic properties were demonstrated by a vibrating sample magnetometer (VSM), which displayed super paramagnetic behaviors for the calcined samples. The present study also substantiated that, in ferrites, the values of the quantities that were acquired by VSM, such as the saturation magnetization and coercivity field, are primarily dependent on the methods of preparation of the ferrites. Electron paramagnetic resonance (EPR) spectroscopy showed the existence of unpaired electrons and measured the peak-to-peak line width (Δ Hpp), the resonant magnetic field (Hr), and the g-factor values. © 2011 Elsevier Ltd. All rights reserved.
Kura A.U.,Institute of Bioscience |
Ali S.H.H.A.,Institute of Bioscience |
Hussein M.Z.,Institute of Advanced Technology |
Fakurazi S.,Institute of Bioscience |
And 2 more authors.
International Journal of Nanomedicine | Year: 2013
A new layered organic-inorganic nanocomposite material with an anti-parkinsonian active compound, L-3-(3,4-dihydroxyphenyl) alanine (levodopa), intercalated into the inorganic interlayers of a Zn/Al-layered double hydroxide (LDH) was synthesized using a direct copre- cipitation method. The resulting nanocomposite was composed of the organic moiety, levodopa, sandwiched between Zn/Al-LDH inorganic interlayers. The basal spacing of the resulting nano-composite was 10.9 Å. The estimated loading of levodopa in the nanocomposite was approximately 16% (w/w). A Fourier transform infrared study showed that the absorption bands of the nanocomposite were characteristic of both levodopa and Zn/Al-LDH, which further confirmed intercalation, and that the intercalated organic moiety in the nanocomposite was more thermally stable than free levodopa. The resulting nanocomposite showed sustained-release properties, so can be used in a controlled-release formulation. Cytotoxicity analysis using an MTT assay also showed increased cell viability of 3T3 cells exposed to the newly synthesized nanocomposite compared with those exposed to pure levodopa after 72 hours of exposure. © 2013 Kura et al, publisher and licensee Dove Medical Press Ltd.
PubMed | Institute of Advanced Technology, Islamic Azad University at Ashkezar, University of Yazd and Shiraz University of Medical Sciences
Type: | Journal: Advances in colloid and interface science | Year: 2016
Combining nanoparticles with carbohydrate has triggered an exponential growth of research activities for the design of novel functional bionanomaterials, nano-carbohydrates. Recent advances in versatile synthesis of glycosylated nanoparticles have paved the way towards diverse biomedical applications. The accessibility of a wide variety of these structured nanosystems, in terms of shape, size, and organization around stable nanoparticles, has readily contributed to their development and application in nanomedicine. Glycosylated gold nanoparticles, glycosylated quantum dots, fullerenes, single-wall nanotubes, and self-assembled glyconanoparticles using amphiphilic glycopolymers or glycodendrimers have received considerable attention for their application in powerful imaging, therapeutic, and biodiagnostic devices. Recently, nano-carbohydrates were used for different types of microarrays to detect proteins and nucleic acids.