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1.
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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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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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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Recent research indicates that marijuana-infused food product (i.e., edible) use is becoming nearly as common as smoking marijuana where medical marijuana is available. This study explores edible use among teens. We conducted four focus groups in the San Francisco Bay Area with youth, ages 15–17. The focus groups were divided by gender and whether they used marijuana. Some teens mentioned edible use at school. Youth reported that teens consume edibles, primarily to reduce the likelihood of getting caught. Edibles are also attractive to those who do not like to smoke or have concerns about smoking. Both male and female respondents suggested that females are more likely than males to prefer edibles over smoking, one reason for which may be to avoid smelling like marijuana smoke. For some young women, edibles may be a way to avoid publicly presenting themselves as marijuana users. Findings also suggest that youth have access to edibles through multiple sources. Youth reported that they can purchase edibles at school from other students who either make the edibles themselves or are reselling edibles obtained from dispensaries. Both users and non-users were aware of potentially negative consequences related to edible use. Some youth mentioned that they have heard of youth dying from edibles, and several reported being concerned about the high produced by edibles. Female non-users appeared to be more concerned than others about edibles and compared them to drinks that could be spiked with drugs. However, sentiment among some male marijuana users was that if you cannot handle edibles you should not be using them. These findings suggest that strategies to curb access to edibles and use among youth, such as restricting sales of edibles with strong youth appeal and educating youth on the risks of edibles, will need to be developed.  相似文献   
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Providing assistance services for sexual activity is becoming of increasing importance to the community of people with disabilities and to mental health professionals. Nevertheless, the literature on this topic is sparse. The aim of this study is to explore potential clients’ and assistants’ views, needs, experiences, opinions, and concerns about sexual assistance (SA) in Italy. Twenty-two semi-structured interviews were conducted with 12 people with a congenital physical disability and 10 would-be assistants. A Grounded Theory approach was used to analyze data. Participants with disabilities considered SA useful. Despite most of them having unfulfilled sexual needs, they would prefer to have their sexual needs met within a romantic relationship. Would-be assistants constructed themselves as people who have a “natural aptitude to being useful”. Results suggest that SA services might represent an opportunity for people with disabilities to discover new ways to satisfy their personal needs and to live more autonomously while, at the same time, allowing would-be sexual assistants to fulfill their desire to be helpful. Nevertheless, the use of SA is likely to only be a part of the answer to fulfilling the sexual needs of people with disabilities.  相似文献   
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Social media has become a major platform for debates on science and health. This commentary argues that while social media can present challenges to communicating important health matters, it can also provide health experts a unique opportunity to engage with and build trust among members of the public.  相似文献   
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The objectives of this study were to assess the sediment contamination with heavy metals and to investigate accordingly the ecological risk posed in the SE of the Danube Delta. Sediments are important in assessing the contamination as they act as reservoirs, transporters and contamination sources. Sediment samples were collected and analysed for lead, cadmium, arsenic and mercury, revealing levels higher than the background, especially for cadmium and mercury (Pb > As > Cd > Hg). Concentrations exceeding the probable effect limit were noticed for arsenic and mercury. The contamination indexes describe the study area as having almost half of the samples as contaminated (pollution load index-PLI 1.04), however the contamination is mostly low-to moderate (modified contamination degree-mCd 1.36). The sediment contamination poses mostly a low ecological risk (RI 94.8). The sediment quality guideline quotient (SQG-Q 0.29) describes a moderate impact, while the probable effect concentration quotient (PEC-Q 0.16) confirms that there are no levels likely to affect the aquatic biota. In our study area, the main Branch of the Danube River and the Secondary Delta are the most affected by contamination, while the narrow, reed abundant channels as the preferred habitat of most aquatic organisms, have a low contamination level.  相似文献   
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Chronic hyperglycaemia is a peculiar feature of diabetes mellitus (DM). Sequential metabolic abnormalities accompanying glucotoxicity are some of its implications. Glucotoxicity most likely corresponds to the vascular intricacy and metabolic alterations, such as increased oxidation of free fatty acids and reduced glucose oxidation. More than half of those with diabetes also develop cardiac abnormalities due to unknown causes, posing a major threat to the currently available marketed preparations which are being used for treating these cardiac complications. Even though impairment in cardiac functioning is the principal cause of death in individuals with type 2 diabetes (T2D), reducing plasma glucose levels has little effect on cardiovascular disease (CVD) risk. In vitro and in vivo studies have demonstrated that inhibitors of sodium glucose transporter (SGLT) represent a putative therapeutic intervention for these pathological conditions. Several clinical trials have reported the efficacy of SGLT inhibitors as a novel and potent antidiabetic agent which along with its antihyperglycaemic activity possesses the potential of effectively treating its associated cardiac abnormalities. Thus, hereby, the present review highlights the role of SGLT inhibitors as a successful drug candidate for correcting the shifts in deregulation of cardiac energy substrate metabolism together with its role in treating diabetes-related cardiac perturbations.  相似文献   
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