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The global plastic production is reaching new altitudes every year. Growing production of petroleum-based plastics has incurred in disposal issues raising the concerns of plastic pollution and impact to the environment. These issues have encouraged innovation and research activities in the field of bioplastics, offering alternatives for conventional plastics. In recent years, global bioplastic production has also witnessed tremendous growth and expansion. Some of the main drivers of this growth are innovative biopolymers such as Polylactic acid (PLA) and Polyhydroxyalkanoates (PHAs). However, industrial expenses to produce bioplastics are much higher when compared to petroleum-derived plastics (e.g. industrial PHA production is estimated to be 5–10 times more expensive than petroleum-derived polymers). In this regard, globally many researchers have investigated for more environmentally friendly and cost-effective alternatives to produce plastics. One potential option to pursue would be to explore agri-food wastes and by-products for bioplastic production. This would not only reduce the volume of wastes and by-products, but also production costs incurred. This review paper provides an overview of bioplastics, including production methods and possibilities of industrial food waste valorization for bioplastic production. 相似文献
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Our study compared means-end exploration in infants at risk (AR) for autism and typically developing (TD) infants using a nested box paradigm. Sixteen AR and 16 TD infants were observed at 9, 12, and 15 months with follow-up at 18 and 24 months. We collected video data on three tasks involving retrieval of a small toy by opening (a) an opaque box, (b) a transparent box, and (c) two nested boxes. Dependent variables included hand bias, time to completion, bilateral hand use, problem-solving strategies used, and tester assistance required. There were no group differences in terms of hand biases. Compared to TD infants, AR infants had lower bilateral hand use, poor problem solving skills, and required greater assistance. Both groups demonstrated age-related improvements in motor and cognitive skills. Means-end exploration provides a window into the bilateral coordination and motor planning/problem-solving abilities of young infants at risk for autism. Lastly, object retrieval tasks could serve as important learning contexts for at-risk infants. 相似文献
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Prabhakaran Dhanasekaran Swaminathan Rajavarman Sivasuriyanarayanan Vinod Selvaganesh Santoshkumar Dattatray Bhat 《Materials》2021,14(9)
Nanocrystalline platinum with different morphologies is synthesized via electrochemical deposition technique. The nucleation mechanism and its structural effect over the electrodeposited Pt on carbon electrodes have been systematically studied. Powder X-ray diffraction, X-ray photoelectron spectroscopy, and field-emission scanning electron microscopy are employed to study nucleation, oxidation states, and Pt structure growth on a carbon electrode. This study reports significant development of Pt metal nanoparticles with different morphologies such as a sphere, flower, core-flower, and rod-like structure directly fabricated on carbon electrode while tuning the deposition parameters such as current density, time, temperature, pH during the deposition process. The proposed electrochemical route represents a superior fabrication procedure for large-scale electrode fabrication compared to a conventional method for preparing membrane electrode assemblies for fuel cell stacks. 相似文献
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Giovanni Merolla Mahendar G. Bhat Paolo Paladini Giuseppe Porcellini 《Journal of orthopaedics and traumatology》2015,16(3):175-183
Calcific tendinitis (CT) of the rotator cuff (RC) muscles in the shoulder is a disorder which remains asymptomatic in a majority of patients. Once manifested, it can present in different ways which can have negative effects both socially and professionally for the patient. The treatment modalities can be either conservative or surgical. There is poor literature evidence on the complications of this condition with little consensus on the treatment of choice. In this review, the literature was extensively searched in order to study and compile together the complications of CT of the shoulder and present it in a clear form to ease the understanding for all the professionals involved in the management of this disorder. Essentially there are five major complications of CT: pain, adhesive capsulitis, RC tears, greater tuberosity osteolysis and ossifying tendinitis. All the above complications have been explained right from their origin to the control measures required for the relief of the patient.Level of evidence 5. 相似文献
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Mammalian target of rapamycin inhibition after solid organ transplantation: can it,and does it,reduce cancer risk? 下载免费PDF全文
The mammalian target of rapamycin (mTOR) inhibitors sirolimus and everolimus has been increasingly used as immunosuppressants for recipients of solid organ transplants. Over the years, potential advantages unique to this class of immunosuppressants have been recognized, including chemoprevention by virtue of their antiproliferative effects. Prevention of malignancy after transplant through mTOR inhibitor‐based immunosuppression may have a specific practical application in transplant recipients with preexisting malignancy including hepatocellular carcinoma or cholangiocarcinoma. This review will reveal how the biochemistry of the mTOR pathway, as it pertains to chemoprevention, can support a clinical role for mTOR inhibitors in the prevention of malignancies, recurrent or de novo, after solid organ transplantation in selected patients. 相似文献