446 research outputs found
A Meta-Analysis of Procedures to Change Implicit Measures
Using a novel technique known as network meta-analysis, we synthesized evidence from 492 studies (87,418 participants) to investigate the effectiveness of procedures in changing implicit measures, which we define as response biases on implicit tasks. We also evaluated these procedures’ effects on explicit and behavioral measures. We found that implicit measures can be changed, but effects are often relatively weak (|ds| \u3c .30). Most studies focused on producing short-term changes with brief, single-session manipulations. Procedures that associate sets of concepts, invoke goals or motivations, or tax mental resources changed implicit measures the most, whereas procedures that induced threat, affirmation, or specific moods/emotions changed implicit measures the least. Bias tests suggested that implicit effects could be inflated relative to their true population values. Procedures changed explicit measures less consistently and to a smaller degree than implicit measures and generally produced trivial changes in behavior. Finally, changes in implicit measures did not mediate changes in explicit measures or behavior. Our findings suggest that changes in implicit measures are possible, but those changes do not necessarily translate into changes in explicit measures or behavior
A dileucine motif in HIV-1 Nef acts as an internalization signal for CD4 downregulation and binds the AP-1 clathrin adaptor
AbstractHuman immunodeficiency virus 1 (HIV-1) Nef downregulates surface expression of CD4, an integral component of the functional HIV receptor complex, through accelerated endocytosis of surface receptors and diminished transport of CD4 from the Golgi network to the plasma membrane [1–3]. HIV-1 Nef also diminishes surface expression of major histocompatibility complex (MHC) class I antigens [4]. In the case of HIV-2 and simian immunodeficiency virus 1 (SIV-1) Nef, aminoterminal tyrosine-based motifs mediate the binding of Nef to the AP-1 and AP-2 adaptors and this interaction appears to be required for CD4 downregulation [5,6]. As these tyrosine motifs are not present in the HIV-1 Nef protein, the molecular basis for the presumed interaction of Nef with components of the endocytic machinery is unknown. Here, we identify a highly conserved dileucine motif in HIV-1 Nef that is required for downregulation of CD4. This motif acts as an internalization signal in the context of a CD8-Nef chimera or in a fusion of the interleukin-2 receptor α with an 11-amino-acid region from Nef containing the dileucine motif. Finally, HIV-1 Nef binds to the AP-1 adaptor, both in vitro and in vivo, in a dileucine-dependent manner. We conclude that this conserved dileucine motif in HIV-1 Nef serves as a key interface for interaction with components of the host protein trafficking machinery. Our findings also reveal an evolutionary difference between HIV-1 and HIV-2/SIV in which the Nef proteins utilize structurally distinct motifs for binding cellular adaptors
Advanced Nanocomposite Coatings of Fusion Bonded Epoxy Reinforced with Amino-Functionalized Nanoparticles for Applications in Underwater Oil Pipelines
The performance of fusion-bonded epoxy coatings can be improved through advanced composite coatings reinforced with nanomaterials. Hence, in this study a novel organic-inorganic nanocomposite finish was designed, synthesized, and characterized, achieved by adding Îł-aminopropyltriethoxysilane modified silica nanoparticles produced via sol-gel process in epoxy-based powder. After the curing process of the coating reinforced with nanoparticles, the formation of a homogenous novel nanocomposite with the development of interfacial reactions between organic-inorganic and inorganic-inorganic components was observed. These hybrid nanostructures produced better integration between nanoparticles and epoxy matrix and improved mechanical properties that are expected to enhance the overall performance of the system against underwater corrosion
Learning word meanings from context: How broadly generalizable?
This study investigated incidental learning of word meanings from context during normal reading. A total of 352 students in third, fifth, and seventh grades read either expository or narrative passages selected from grade-level textbooks, and after six days were tested on their knowledge of difficult words from the passages. Small but reliable gains in knowledge of words from the passages read were found at all grade and ability levels. Learning from written context is estimated to account for a third or more of the words acquired annually by school-age children. The results were taken to suggest that getting children to read more should be an effective means for promoting vocabulary growth regardless of grade or ability
Back to the future:re-establishing guinea pig in vivo asthma models
Research using animal models of asthma is currently dominated by mouse models. This has been driven by the comprehensive knowledge on inflammatory and immune reactions in mice, as well as tools to produce genetically modified mice. Many of the identified therapeutic targets influencing airway hyper-responsiveness and inflammation in mouse models, have however been disappointing when tested clinically in asthma. It is therefore a great need for new animal models that more closely resemble human asthma. The guinea pig has for decades been used in asthma research and a comprehensive table of different protocols for asthma models is presented. The studies have primarily been focused on the pharmacological aspects of the disease, where the guinea pig undoubtedly is superior to mice. Further reasons are the anatomical and physiological similarities between human and guinea pig airways compared with that of the mouse, especially with respect to airway branching, neurophysiology, pulmonary circulation and smooth muscle distribution, as well as mast cell localization and mediator secretion. Lack of reagents and specific molecular tools to study inflammatory and immunological reactions in the guinea pig has however greatly diminished its use in asthma research. The aim in this position paper is to review and summarize what we know about different aspects of the use of guinea pig in vivo models for asthma research. The associated aim is to highlight the unmet needs that have to be addressed in the future
Microwave assisted synthesis of novel bis-flavone dimers as new anticancer agents
In this study we describe a microwave based click chemistry method used to prepare a family of novel bis-flavone dimers. The substituted 7-hydroxy and 4’-hydroxy flavonoids were linked through a triazole ring. The compounds were easily synthesized and purified in high yields. The bis-flavonoids were tested on different cell lines including HCT116, HepG2, MCF7 and MOLT-4. Several analogues showed to have anticancer activity with IC50 values in the range of 20-60 µM. Flavonoids are known for their anticancer properties and this method provides the basis for new medicinal structures
Overfishing Drives Over One-Third of All Sharks and Rays Toward a Global Extinction Crisis
The scale and drivers of marine biodiversity loss are being revealed by the International Union for Conservation of Nature (IUCN) Red List assessment process. We present the first global reassessment of 1,199 species in Class Chondrichthyes-sharks, rays, and chimeras. The first global assessment (in 2014) concluded that one-quarter (24%) of species were threatened. Now, 391 (32.6%) species are threatened with extinction. When this percentage of threat is applied to Data Deficient species, more than one-third (37.5%) of chondrichthyans are estimated to be threatened, with much of this change resulting from new information. Three species are Critically Endangered (Possibly Extinct), representing possibly the first global marine fish extinctions due to overfishing. Consequently, the chondrichthyan extinction rate is potentially 25 extinctions per million species years, comparable to that of terrestrial vertebrates. Overfishing is the universal threat affecting all 391 threatened species and is the sole threat for 67.3% of species and interacts with three other threats for the remaining third: loss and degradation of habitat (31.2% of threatened species), climate change (10.2%), and pollution (6.9%). Species are disproportionately threatened in tropical and subtropical coastal waters. Science-based limits on fishing, effective marine protected areas, and approaches that reduce or eliminate fishing mortality are urgently needed to minimize mortality of threatened species and ensure sustainable catch and trade of others. Immediate action is essential to prevent further extinctions and protect the potential for food security and ecosystem functions provided by this iconic lineage of predators
The AGB superwind speed at low metallicity
We present the results of a survey for OH maser emission at 1612 MHz from
dust-enshrouded AGB stars and supergiants in the LMC and SMC, with the Parkes
radio telescope, aimed at deriving the speed of the superwind from the
double-peaked OH maser profiles. Out of 8 targets in the LMC we detected 5, of
which 3 are new detections - no maser emission was detected in the two SMC
targets. We detected for the first time the redshifted components of the OH
maser profile in the extreme red supergiant IRAS 04553-6825, confirming the
suspicion that its wind speed had been severely underestimated. Despite a much
improved spectrum for IRAS 04407-7000, which was known to exhibit a
single-peaked OH maser, no complementary peak could be detected. The new
detection in IRAS 05003-6712 was also single-peaked, but for two other new
detections, IRAS 04498-6842 and IRAS 05558-7000, wind speeds could be
determined from their double-peaked maser profiles. The complete sample of
known OH/IR stars in the LMC is compared with a sample of OH/IR stars in the
galactic centre. The LMC sources generally show a pronounced asymmetry between
the bright blueshifted maser emission and weaker redshifted emission, which we
attribute to the greater contribution of amplification of radiation coming
directly from the star itself as the LMC sources are both more luminous and
less dusty than their galactic centre counterparts. We confirm that the OH
maser strength is a measure of the dust (rather than gas) mass-loss rate. At a
given luminosity or pulsation period, the wind speed in LMC sources is lower
than in galactic centre sources, and the observed trends confirm simple
radiation-driven wind theory if the dust-to-gas ratio is approximately
proportional to the metallicity.Comment: 13 pages, 18 figures. Accepted for publication in MNRA
Nanophotonics for ultra-thin crystalline silicon photovoltaics: when photons (actually) meet electrons
- …