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1.
This paper presents a study on the sociocognitive effects of news frames on immigration. One hundred and eighty‐six individuals were exposed to a newspaper story on increased immigration to Spain. The newspaper highlighted (a) the positive (economic contribution frame) versus negative (crime growth frame) consequences and (b) the group cue—Latinos versus Moroccans. In contrast with economic contribution frame, crime growth frame stimulated more negative cognitive responses toward immigration, increased the salience of immigration as a problem, generated a negative attitude toward immigration, and induced greater disagreement with positive beliefs about the consequences of immigration for the country. We conceptualized the framing effect as a heuristic process in which peripheral cues in the news story guided information processing.  相似文献   

2.
This study investigates media effects on stereotypic attitudes toward immigrants in a political campaign that dealt with the naturalization of immigrants. By combining a content analysis of the campaign coverage with a 2‐wave panel survey, the study found that negative news portrayals of immigrants increased stereotypic attitudes in the public in the course of the campaign. Additionally, the frequent exposure to positive news portrayals of immigrants reduced the activation of negative outgroup attitudes. However, these findings are contingent on people's issue‐specific knowledge. Only people with low to moderate knowledge were influenced by negative and positive news stories about immigrants in the campaign. Well‐informed people were resistant to the effects of positive and news portrayals of immigrants.  相似文献   

3.
This study examined whether the positive or negative valence of a news story, and the race of the character portrayed in the story, would influence Black or White readers' selection of a story. The study employed selective exposure methodology to unobtrusively measure story selections among Black and White readers as they browsed a news site. The results demonstrated Black newsreaders were more likely to select and read positive and negative stories featuring their racial ingroup, and more likely to select and read negative vis‐à‐vis positive stories about their outgroup. In contrast, Whites' story preference was not affected by story valence or character race. Theoretical assumptions from social identity, social comparison, and social cognitive theories are used to explain the findings.  相似文献   

4.
This study differentiates two explanations of agenda‐setting effects: agenda cueing (the influence of the mere fact of news coverage) and agenda reasoning (the influence of reasons for problem importance in the content of news stories). We isolate the two using a report summarizing recent news coverage as the experimental stimulus, instead of actual news coverage, allowing independent manipulation of agenda cue exposure and agenda reason exposure. A key moderator in both processes is gatekeeping trust, or trust in the media to base coverage decisions on problem importance judgments. Specifically, pure cues (without agenda reasons) are more influential on those with higher gatekeeping trust, and among those with low gatekeeping trust, cues are more influential when backed by agenda reasons.  相似文献   

5.
A planar surface cell structure has been utilized to investigate a polymer light‐emitting electrochemical cell (LEC), consisting of an active‐material mixture of poly[2‐methoxy‐5‐(2′‐ethylhexyloxy)‐1,4‐phenylenevinylene] (MEH‐PPV) and an ionic liquid, tetra‐n‐butylammonium trifluoromethanesulfonate, contacted by Au electrodes. It is shown that diffuse and needle‐shaped doping fronts originate from the electrodes (p‐type from the positive electrode and n‐type from the negative electrode) during the charging process at a temperature (T) of 393 K. After a turn‐on time, a significant portion of the doping fronts makes contact close to the negative electrode to form a light‐emitting p–i–n junction, but at some points p‐type doping protrudes all the way to the negative electrode to form what are effectively micro shorts. It is shown that the consequences of such doping‐induced micro shorts during a subsequent stabilized “frozen junction” operation at T = 200 K are drastic: the current‐rectification ratio (RR) is low and the quantum efficiency (QE) is far from optimum. Both RR and QE increase significantly during long‐term operation under frozen‐junction conditions, demonstrating that the lifetime of the doping‐induced micro shorts is limited even under such stabilized conditions. Still, it is clear that it is critical for the optimization and further development of LECs to find new types of active material and electrode combinations that allow for formation of a continuous p–i–n junction in the center of the interelectrode gap.  相似文献   

6.
The 193 nm photochemistry of (aminoethylaminomethyl)phenethylsiloxane (PEDA) self‐assembled monolayers (SAMs) under ambient conditions is described. The primary photodegradation pathways at low exposure doses (< 100 mJ cm–2) are benzylic C–N bond cleavage (ca. 68 %), with oxidation of the benzyl C to the aldehyde, and Si–C bond cleavage (ca. 32 %). Amine‐containing photoproducts released from the SAM during exposure remain physisorbed on the surface, where they undergo secondary photolysis leading to their complete degradation and removal after ca. 1200 mJ cm–2. NaCl(aq) post‐exposure rinsing removes the physisorbed materials, showing that degradation of the original PEDA species (leaving Si–OH) is substantially complete after ca. 450 mJ cm–2. Consequently, patterned, rinsed PEDA SAMs function as efficient templates for fabrication of high‐resolution, negative‐tone, electroless metal and DNA features with good selectivity at low dose (i.e., ca. 400 mJ cm–2) via materials grafting to the intact amines remaining in the unirradiated PEDA SAM regions.  相似文献   

7.
Cellulose paper (CP)‐based asymmetrical thin film supercapacitors (ATFSCs) have been considered to be a novel platform for inexpensive and portable devices as the CP is low‐cost, lightweight, and can be rolled or folded into 3D configurations. However, the low energy density and poor cycle stability are serious bottlenecks for the development of CP‐based ATFSCs. Here, sandwich‐structured graphite/Ni/Co2NiO4‐CP is developed as positive electrode and the graphite/Ni/AC‐CP as negative electrode for flexible and high‐performance ATFSCs. The fabricated graphite/Ni/Co2NiO4‐CP positive electrode shows a superior areal capacitance (734 mF/cm2 at 5 mV/s) and excellent cycling performance with ≈97.6% Csp retention after 15 000 cycles. The fabricated graphite/Ni/AC‐CP negative electrode also exhibits large areal capacitance (180 mF/cm2 at 5 mV/s) and excellent cycling performance with ≈98% Csp retention after 15 000 cycles. The assembled ATFSCs based on the sandwich‐structured graphite/Ni/Co2NiO4‐CP as positive electrode and graphite/Ni/AC‐CP as negative electrode exhibit large volumetric Csp (7.6 F/cm3 at 5 mV/s), high volumetric energy density (2.48 mWh/cm3, 80 Wh/kg), high volumetric power density (0.79 W/cm3, 25.6 kW/kg) and excellent cycle stability (less 4% Csp loss after 20 000 cycles). This study shows an important breakthrough in the design and fabrication of high‐performance and flexible CP‐based electrodes and ATFSCs.  相似文献   

8.
Zwitter polymers are defined as polymers that undergo transformation from a linear to a crosslinked structure under electron‐beam irradiation. A resist polymer may be either linear or crosslinked, depending on electron‐beam dosage. The structural transformation of acrylic resin make it suitable for applications in positive and negative resists in the semiconductor field. The contrast ratio and threshold dose both increase with increasing resist thickness for both the positive and negative resists, while the positive resist exhibits better contrast than the negative. The intensity of the characteristic Fourier‐transform infrared absorption band at 1612 cm–1 (vinyl group) is used to explain the phenomena behind these resist transformations. We evaluate the effects of two important processing conditions: the soft baking and post‐exposure baking temperatures. Pattern resolution decreases upon increasing the baking temperature, except for soft baking of the negative resist. The effect of electron dose on the pattern resolution is also discussed in detail for both resists. High electron‐beam exposure does not improve the etching resistance of the resist because of the porous nature of the resist that develops after high‐dosage irradiation.  相似文献   

9.
Across all age groups, entertainment is one of the most important motivations for media use. Relatively little is known, though, about the development of entertainment experience over the life span. Does entertainment actually mean the same thing to young and older people? Based on theories of adult emotional development, affect regulation, and well‐being, this study predicted and found that in terms of entertainment gratifications sought, young adults were more interested than older adults in emotionally intense entertainment experiences such as thrilling and tear‐jerking experiences, whereas older adults were more interested in contemplative entertainment experiences. However, in terms of gratifications obtained, ratings of film scenes showed that the same types of gratifications obtained predicted more positive evaluations independent of age.  相似文献   

10.
For a well-functioning democracy, it is crucial that children consume news. However, news can elicit overly negative emotions and discourage engagement in children. The question, therefore, is how news can be adapted to children's sensitivities and needs but can still inform them. This study investigated whether constructive reporting (solution-based narratives including positive emotions) in news about negative events improved emotional responses and encouraged engagement (intention and inspiration to engage). In an experiment, 8–13-year-olds (N = 332) read a story containing either constructive elements or not. Constructive news elicited lower levels of negative emotional responses and provided more inspiration for engagement than nonconstructive news. These promising findings open doors for follow-up investigations regarding constructive news reporting, also among adult audiences.  相似文献   

11.
Periodic mesoporous organosilica (PMO) thin films have been produced using an evaporation‐induced self‐assembly (EISA) spin‐coating procedure and a cationic surfactant template. The precursors are silsesquioxanes of the type (C2H5O)3Si–R–Si(OC2H5)3 or R′–[Si(OC2H5)3]3 with R = methene (–CH2–), ethylene (–C2H2–), ethene (–C2H4–), 1,4‐phenylene (C6H4), and R′ = 1,3,5‐phenylene (C6H3). The surfactant is successfully removed by solvent extraction or calcination without any significant Si–C bond cleavage of the organic bridging groups R and R′ within the channel walls. The materials have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X‐ray diffraction (PXRD), and 29Si and 13C magic‐angle spinning (MAS) NMR spectroscopy. The d‐spacing of the PMOs is found to be a function of R. Nanoindentation measurements reveal increased mechanical strength and stiffness for the PMOs with R = CH2 and C2H4 compared to silica. Films with different organic‐group content have been prepared using mixtures of silsesquioxane and tetramethylorthosilicate (TMOS) precursors. The dielectric constant (k) is found to decrease with organic content, and values as low as 1.8 have been measured for films thermally treated to cause a “self‐hydrophobizing” bridging‐to‐terminal transformation of the methene to methyl groups with concomitant loss of silanols. Increasing the organic content and thermal treatment also increases the resistance to moisture adsorption in 60 and 80 %‐relative‐humidity (RH) environments. Methene PMO films treated at 500 °C are found to be practically unchanged after five days exposure to 80 % RH. These low dielectric constants, plus the good thermal and mechanical stability and the hydrophobicity suggest the potential utility of these films as low‐k layers in microelectronics.  相似文献   

12.
A memristive nonvolatile logic‐in‐memory circuit can provide a novel energy‐efficient computing architecture for battery‐powered flexible electronics. However, the cell‐to‐cell interference existing in the memristor crossbar array impedes both the reading process and parallel computing. Here, it is demonstrated that integration of an amorphous In‐Zn‐Sn‐O (a‐IZTO) semiconductor‐based selector (1S) device and a poly(1,3,5‐trivinyl‐1,3,5‐trimethyl cyclotrisiloxane) (pV3D3)‐based memristor (1M) on a flexible substrate can overcome these problems. The developed a‐IZTO‐based selector device, having a Pd/a‐IZTO/Pd structure, exhibits nonlinear current–voltage (IV) characteristics with outstanding stability against electrical and mechanical stresses. Its underlying conduction mechanism is systematically determined via the temperature‐dependent IV characteristics. The flexible one‐selector?one‐memristor (1S–1M) array exhibits reliable electrical characteristics and significant leakage current suppression. Furthermore, single‐instruction multiple‐data (SIMD), the foundation of parallel computing, is successfully implemented by performing NOT and NOR gates over multiple rows within the 1S–1M array. The results presented here will pave the way for development of a flexible nonvolatile logic‐in‐memory circuit for energy‐efficient flexible electronics.  相似文献   

13.
This study examined how intrinsic as well as perceived message features affect the extent to which online health news stories prompt audience selections and social retransmissions, and how news‐sharing channels (e‐mail vs. social media) shape what goes viral. The study analyzed actual behavioral data on audience viewing and sharing of New York Times health news articles, and associated article content and context data. News articles with high informational utility and positive sentiment invited more frequent selections and retransmissions. Articles were also more frequently selected when they presented controversial, emotionally evocative, and familiar content. Informational utility and novelty had stronger positive associations with e‐mail‐specific virality, whereas emotional evocativeness, content familiarity, and exemplification played a larger role in triggering social media‐based retransmissions.  相似文献   

14.
Organic field‐effect transistors suffer from ultra‐high operating voltages in addition to their relative low mobility. A general approach to low‐operating‐voltage organic field‐effect transistors (OFETs) using donor/acceptor buffer layers is demonstrated. P‐type OFETs with acceptor molecule buffer layers show reduced operating voltages (from 60–100 V to 10–20 V), with mobility up to 0.19 cm2 V?1 s?1 and an on/off ratio of 3 × 106. The subthreshold slopes of the devices are greatly reduced from 5–12 V/decade to 1.68–3 V/decade. This favorable combination of properties means that such OFETs can be operated successfully at voltages below 20 V (|VDS| ≤ 20 V, |VGS| ≤ 20 V). This method also works for n‐type semiconductors. The reduced operating voltage and low pinch‐off voltage contribute to the improved ordering of the polycrystalline films, reduced grain boundary resistance, and steeper subthreshold slopes.  相似文献   

15.
A newly synthesized high‐k polymeric insulator for use as gate dielectric layer for organic field‐effect transistors (OFETs) obtained by grafting poly(methyl methacrylate) (PMMA) in poly(vinylidene fluoride‐trifluoroethylene) (P(VDF‐TrFE)) via atom transfer radical polymerization transfer is reported. This material design concept intents to tune the electrical properties of the gate insulating layer (capacitance, leakage current, breakdown voltage, and operational stability) of the high‐k fluorinated polymer dielectric without a large increase in operating voltage by incorporating an amorphous PMMA as an insulator. By controlling the grafted PMMA percentage, an optimized P(VDF‐TrFE)‐g‐PMMA with 7 mol% grafted PMMA showing reasonably high capacitance (23–30 nF cm?2) with low voltage operation and negligible current hysteresis is achieved. High‐performance low‐voltage‐operated top‐gate/bottom‐contact OFETs with widely used high mobility polymer semiconductors, poly[[2,5‐bis(2‐octyldodecyl)‐2,3,5,6‐tetrahydro‐3,6‐dioxopyrrolo [3,4‐c]pyrrole‐1,4‐diyl]‐alt‐[[2,2′‐(2,5‐thiophene)bis‐thieno(3,2‐b)thiophene]‐5,5′‐diyl]] (DPPT‐TT), and poly([N,N′‐bis(2‐octyldodecyl)‐naphthalene‐1,4,5,8‐bis(dicarboximide)‐2,6‐diyl]‐alt‐5,5′‐(2,2′‐bithiophene)) are demonstrated here. DPPT‐TT OFETs with P(VDF‐TrFE)‐g‐PMMA gate dielectrics exhibit a reasonably high field‐effect mobility of over 1 cm2 V?1 s?1 with excellent operational stability.  相似文献   

16.
Reaching target audiences is of crucial importance for the success of health communication campaigns, but individuals may avoid health messages if they challenge their beliefs or behaviors. A lab study (N = 419) examined effects of messages' consistency with participants' behavior and source credibility on selective exposure for 4 health lifestyle topics. Drawing on self‐regulation theory and dissonance theory, 3 motivations were examined: self‐bolstering, self‐motivating, and self‐defending. Prior behavior predicted selective exposure across topics, reflecting self‐bolstering. Standard‐behavior discrepancies also affected selective exposure, consistent with self‐motivating rather than self‐defending. Selective exposure to high‐credibility sources advocating for organic food, fruits and vegetable consumption, exercise, and limiting coffee all fostered accessibility of related standards, whereas messages from low‐credibility sources showed no such impact.  相似文献   

17.
With the emergence of antibiotic resistance, developing new antibiotics and therapies for combating bacterial infections is urgently needed. Herein, a series of quaternized fluorescent silicon nanoparticles (SiNPs) are facilely prepared by the covalent reaction between amine‐functionalized SiNPs and carboxyl‐containing N‐alkyl betaines. It is found that the bactericidal efficacy of these quaternized SiNPs increases with the length of the N‐alkyl chain, and SiNPs conjugated with N,N‐dimethyl‐N‐octadecylbetaine (BS‐18), abbreviated as SiNPs‐C18, show the best antibacterial effect, whose minimum inhibitory concentrations for Gram‐positive bacteria are 1–2 μg mL?1. In vivo tests further confirm that SiNPs‐C18 have excellent antibacterial efficacy and greatly reduce bacterial load in the infectious sites. The SiNPs‐C18 exhibit low cytotoxicity toward mammalian cells (including normal liver and lung cells, red blood cells, and macrophages), enabling them to be useful for clinical applications. Besides, the quaternized SiNPs exhibit polarity‐dependent fluorescence emission property and can selectively image Gram‐positive bacteria, thereby providing a simple method to successfully differentiate Gram‐positive and Gram‐negative bacteria. The present work represents the first example that successfully turns fluorescent SiNPs into metal‐free NP‐based antibiotics with simultaneous bacterial imaging and killing capability, which broadens the applications of fluorescent SiNPs and advances the development of novel antibacterial agents.  相似文献   

18.
Development of multifunctional nanoscale coordination polymers (NCPs) allowing for T1‐ and T2‐weighted targeted magnetic resonance (MR) imaging of tumors could significantly improve the diagnosis accuracy. In this study, nanoscale coordination polymers (NCPs) with a diameter of ≈80 nm are obtained with 1,1′‐dicarboxyl ferrocene (Fc) as building blocks and magnetic gadolinium(III) ions as metallic nodes using a nanoprecipitation method, then further aminated through silanization. The amine‐functionalized Fc‐Gd@SiO2 NCPs enable the covalent conjugation of a fluorescent rhodamine dye (RBITC) and an arginine‐glycine‐aspartic acid (RGD) peptide as a targeting ligand onto their surface. The formed water‐dispersible Fc‐Gd@SiO2(RBITC)–RGD NCPs exhibit a low cytotoxicity, as confirmed by MTT assay. They have a longitudinal relaxivity (r1) of 5.1 mM?1 s?1 and transversal relaxivity (r2) of 21.7 mM?1 s?1, suggesting their possible use as both T1‐positive and T2‐negative contrast agents. In vivo MR imaging experiments show that the signal of tumor over‐expressing high affinity αvβ3 integrin from T1‐weighted MR imaging is positively enhanced 47±5%, and negatively decreased 33±5% from T2‐weighted MR imaging after intravenous injection of Fc‐Gd@SiO2(RBITC)–RGD NCPs.  相似文献   

19.
Thermotropic liquid‐crystalline (LC) electrolytes for lithium‐ion batteries are developed for the first time. A rod‐like LC molecule having a cyclic carbonate moiety is used to form self‐assembled two‐dimensional ion‐conductive pathways with lithium salts. Electrochemical and thermal stability, and efficient ionic conduction is achieved for the liquid crystal. The mixture of the carbonate derivative and lithium bis(trifluoromethylsulfonyl)imide is successfully applied as an electrolyte in lithium‐ion batteries. Reversible charge–discharge for both positive and negative electrodes is observed for the lithium‐ion batteries composed of the LC electrolyte.  相似文献   

20.
Endured, low‐cost, and high‐performance flexible perovskite solar cells (PSCs) featuring lightweight and mechanical flexibility have attracted tremendous attention for portable power source applications. However, flexible PSCs typically use expensive and fragile indium–tin oxide as transparent anode and high‐vacuum processed noble metal as cathode, resulting in dramatic performance degradation after continuous bending or thermal stress. Here, all‐carbon‐electrode‐based flexible PSCs are fabricated employing graphene as transparent anode and carbon nanotubes as cathode. All‐carbon‐electrode‐based flexible devices with and without spiro‐OMeTAD (2,2′,7,7′‐tetrakis‐(N,N‐di‐p‐methoxyphenylamine)‐9,9′‐spirobifluorene) hole conductor achieve power conversion efficiencies (PCEs) of 11.9% and 8.4%, respectively. The flexible carbon‐electrode‐based solar cells demonstrate superior robustness against mechanical deformation in comparison with their counterparts fabricated on flexible indium–tin oxide substrates. Moreover, all carbon‐electrode‐based flexible PSCs also show significantly enhanced stability compared to the flexible devices with gold and silver cathodes under continuous light soaking or 60 °C thermal stress in air, retaining over 90% of their original PCEs after 1000 h. The promising durability and stability highlight that flexible PSCs are fully compatible with carbon materials and pave the way toward the realization of rollable and low‐cost flexible perovskite photovoltaic devices.  相似文献   

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