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1.
Chem Soc Rev ; 53(11): 5956-6010, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38721851

RESUMO

Soft actuators, pivotal for converting external energy into mechanical motion, have become increasingly vital in a wide range of applications, from the subtle engineering of soft robotics to the demanding environments of aerospace exploration. Among these, electrochemically-driven actuators (EC actuators), are particularly distinguished by their operation through ion diffusion or intercalation-induced volume changes. These actuators feature notable advantages, including precise deformation control under electrical stimuli, freedom from Carnot efficiency limitations, and the ability to maintain their actuated state with minimal energy use, akin to the latching state in skeletal muscles. This review extensively examines EC actuators, emphasizing their classification based on diverse material types, driving mechanisms, actuator configurations, and potential applications. It aims to illuminate the complicated driving mechanisms of different categories, uncover their underlying connections, and reveal the interdependencies among materials, mechanisms, and performances. We conduct an in-depth analysis of both conventional and emerging EC actuator materials, casting a forward-looking lens on their trajectories and pinpointing areas ready for innovation and performance enhancement strategies. We also navigate through the challenges and opportunities within the field, including optimizing current materials, exploring new materials, and scaling up production processes. Overall, this review aims to provide a scientifically robust narrative that captures the current state of EC actuators and sets a trajectory for future innovation in this rapidly advancing field.

2.
Biochem J ; 480(17): 1411-1427, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37622331

RESUMO

Metabolic reprogramming, including increased glucose uptake and lactic acid excretion, is a hallmark of cancer. The glycolytic 'gatekeeper' enzyme phosphofructokinase-1 (PFK1), which catalyzes the step committing glucose to breakdown, is dysregulated in cancers. While altered PFK1 activity and expression in tumors have been demonstrated, little is known about the effects of cancer-associated somatic mutations. Somatic mutations in PFK1 inform our understanding of allosteric regulation by identifying key amino acid residues involved in the regulation of enzyme activity. Here, we characterized mutations disrupting an evolutionarily conserved salt bridge between aspartic acid and arginine in human platelet (PFKP) and liver (PFKL) isoforms. Using purified recombinant proteins, we showed that disruption of the Asp-Arg pair in two PFK1 isoforms decreased enzyme activity and altered allosteric regulation. We determined the crystal structure of PFK1 to 3.6 Šresolution and used molecular dynamic simulations to understand molecular mechanisms of altered allosteric regulation. We showed that PFKP-D564N had a decreased total system energy and changes in the electrostatic surface potential of the effector site. Cells expressing PFKP-D564N demonstrated a decreased rate of glycolysis, while their ability to induce glycolytic flux under conditions of low cellular energy was enhanced compared with cells expressing wild-type PFKP. Taken together, these results suggest that mutations in Arg-Asp pair at the interface of the catalytic-regulatory domains stabilizes the t-state and presents novel mechanistic insight for therapeutic development in cancer.


Assuntos
Neoplasias , Fosfofrutoquinase-1 , Humanos , Regulação Alostérica , Eletricidade Estática , Fosfofrutoquinase-1/genética , Metabolismo dos Carboidratos , Neoplasias/genética
3.
J Clin Psychol ; 77(11): 2609-2625, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34115383

RESUMO

OBJECTIVES: Misophonia is a highly prevalent yet understudied condition characterized by aversion toward particular environmental sounds. Oral/nasal sounds (e.g., chewing, breathing) have been the focus of research, but variable experiences warrant an objective investigation. Experiment 1 asked whether human-produced oral/nasal sounds were more aversive than human-produced nonoral/nasal sounds and non-human/nature sounds. Experiment 2 additionally asked whether machine-learning algorithms could predict the presence and severity of misophonia. METHOD: Sounds were presented to individuals with misophonia (Exp.1: N = 48, Exp.2: N = 45) and members of the general population (Exp.1: N = 39, Exp.2: N = 61). Aversiveness ratings to each sound were self-reported. RESULTS: Sounds from all three source categories-not just oral/nasal sounds-were rated as significantly more aversive to individuals with misophonia than controls. Further, modeling all sources classified misophonia with 89% accuracy and significantly predicted misophonia severity (r = 0.75). CONCLUSIONS: Misophonia should be conceptualized as more than an aversion to oral/nasal sounds, which has implications for future diagnostics and experimental consistency moving forward.


Assuntos
Hiperacusia , Mastigação , Humanos , Autorrelato , Som
4.
J Pediatr Orthop ; 39(2): e120-e124, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29049268

RESUMO

BACKGROUND: Long arm cast immobilization after operative and nonoperative treatment of pediatric upper extremity fractures is common. The use of a sling to aid in carrying the casted extremity as well as provide further immobilization is also common practice. Off-the-shelf slings vary in quality and fit, can be confusing for parents/patients to apply, and lead to frustration and dissatisfaction with its use. The purpose of this investigation was to compare patient/parent centered outcomes after the use of a customized sling compared with a standard sling by utilizing a prospective, randomized-controlled trial. We hypothesized that patients and their parents would find the "Providence" Pedi Cast-Sling (PPCS) to be more convenient and be more satisfied with its use compare with a standard sling. METHODS: Eligible subjects included patients 0 to 18 years old, evaluated at an urban, tertiary care pediatric emergency department (ED), who sustained an upper extremity fracture that required placement of a long-arm cast. Exclusion criteria were: open fractures; fractures at multiple levels; fractures requiring urgent/emergent surgery; admitted patients; bivalved casts. Patients were randomized to receive a standard sling or a PPCS. Questionnaires assessing patient/parent satisfaction, preferences, sling-use, and pain level were collected at patients' first follow-up visit. RESULTS: A total of 100 patients were randomized with 71 questionnaires available for analysis (39 standard sling vs. 32 PPCS). There were statistically significant differences for satisfaction scores for all related questions between patients who received a PPCS compared with a standard sling. Patients and their parents were more likely to choose the PPCS (P=0.001), were more satisfied with the PPCS (P<0.006), and reported the PPCS to be more convenient than a standard sling (P<0.001). Patients who received a PPCS wore the sling for a greater number of hours during the day (10.3±7.1 h) compared with those who received a standard sling (5.9±5.0 h) (P=0.004). CONCLUSIONS: The "Providence" Pedi Cast-Sling is a superior alternative to an off-the-shelf sling when used after the application of a long-arm cast providing greater convenience, compliance, and satisfaction to both patients and families. LEVEL OF EVIDENCE: Level I-Prospective randomized-controlled trial.


Assuntos
Traumatismos do Braço/terapia , Moldes Cirúrgicos , Fraturas Ósseas/terapia , Satisfação do Paciente , Contenções , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pais/psicologia , Estudos Prospectivos
5.
J Arthroplasty ; 33(5): 1520-1523, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29398260

RESUMO

BACKGROUND: A prior survey of members of the American Association of Hip and Knee Surgeons revealed that 78% of responding surgeons were named as a defendant in at least 1 lawsuit, and 69% of these lawsuits were dismissed or settled out of court. The most common sources of litigation were nerve injury, limb-length discrepancy, and infection. This study examined common reasons for lawsuits after total joint arthroplasty (TJA) in a single metropolitan area. METHODS: A retrospective review of lawsuits filed between 2009 and 2015 in a 5-county metropolitan area was performed, including 30 hospitals and 113 TJA surgeons. Complaints underwent a manual review to determine the number of lawsuits and the specific allegations filed against each surgeon. RESULTS: Thirty-one (27.4%) surgeons were named as a defendant in at least 1 lawsuit. Eighty-three total lawsuits were filed during the period, 50 of which were dismissed or settled outside of court. Top reasons for lawsuits were, in descending order, infection, nerve injury, chronic pain, vascular injury, periprosthetic fracture, retention of foreign body, dislocation, limb-length discrepancy, venous thromboembolism, loosening, compartment syndrome, and other medical complaints. CONCLUSION: Infection appears to be the basis of most lawsuits after TJA. Surgeons should be aware of the potential for a lawsuit for complications and should strive to better communicate with patients regarding preoperative informed consent and disclosure after adverse events. Surgeons should minimize performing surgery in patients at high risk of complications, such as patients with a higher likelihood of developing postoperative infection or patients on chronic pain medications.


Assuntos
Artroplastia de Quadril/legislação & jurisprudência , Artroplastia do Joelho/legislação & jurisprudência , Imperícia/estatística & dados numéricos , Infecções Relacionadas à Prótese/etiologia , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Cidades , Hospitais , Humanos , Consentimento Livre e Esclarecido , Articulação do Joelho , New England , Fraturas Periprotéticas/etiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Cirurgiões/legislação & jurisprudência
6.
J Med Internet Res ; 18(9): e235, 2016 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-27627853

RESUMO

BACKGROUND: Federal and state public health agencies in the United States are increasingly using digital advertising and social media to promote messages from broader multimedia campaigns. However, little evidence exists on population-level campaign awareness and relative cost efficiencies of digital advertising in the context of a comprehensive public health education campaign. OBJECTIVE: Our objective was to compare the impact of increased doses of digital video and television advertising from the 2013 Tips From Former Smokers (Tips) campaign on overall campaign awareness at the population level. We also compared the relative cost efficiencies across these media platforms. METHODS: We used data from a large national online survey of approximately 15,000 US smokers conducted in 2013 immediately after the conclusion of the 2013 Tips campaign. These data were used to compare the effects of variation in media dose of digital video and television advertising on population-level awareness of the Tips campaign. We implemented higher doses of digital video among selected media markets and randomly selected other markets to receive similar higher doses of television ads. Multivariate logistic regressions estimated the odds of overall campaign awareness via digital or television format as a function of higher-dose media in each market area. All statistical tests used the .05 threshold for statistical significance and the .10 level for marginal nonsignificance. We used adjusted advertising costs for the additional doses of digital and television advertising to compare the cost efficiencies of digital and television advertising on the basis of costs per percentage point of population awareness generated. RESULTS: Higher-dose digital video advertising was associated with 94% increased odds of awareness of any ad online relative to standard-dose markets (P<.001). Higher-dose digital advertising was associated with a marginally nonsignificant increase (46%) in overall campaign awareness regardless of media format (P=.09). Higher-dose television advertising was associated with 81% increased odds of overall ad awareness regardless of media format (P<.001). Increased doses of television advertising were also associated with significantly higher odds of awareness of any ad on television (P<.001) and online (P=.04). The adjusted cost of each additional percentage point of population-level reach generated by higher doses of advertising was approximately US $440,000 for digital advertising and US $1 million for television advertising. CONCLUSIONS: Television advertising generated relatively higher levels of overall campaign awareness. However, digital video was relatively more cost efficient for generating awareness. These results suggest that digital video may be used as a cost-efficient complement to traditional advertising modes (eg, television), but digital video should not replace television given the relatively smaller audience size of digital video viewers.


Assuntos
Publicidade/métodos , Educação em Saúde/métodos , Promoção da Saúde/métodos , Abandono do Hábito de Fumar , Fumar , Televisão , Adolescente , Adulto , Publicidade/economia , Conscientização , Análise Custo-Benefício , Feminino , Educação em Saúde/economia , Promoção da Saúde/economia , Humanos , Modelos Logísticos , Masculino , Meios de Comunicação de Massa , Pessoa de Meia-Idade , Multimídia , Análise Multivariada , Saúde Pública , Mídias Sociais , Inquéritos e Questionários , Estados Unidos , Adulto Jovem
7.
J Med Internet Res ; 18(3): e64, 2016 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-26983849

RESUMO

BACKGROUND: Measuring the impact of online health campaigns is challenging. Ad click-through rates are traditionally used to measure campaign reach, but few Internet users ever click on ads. Alternatively, self-reported exposure to digital ads would be prone to recall bias. Furthermore, there may be latency effects whereby people do not click on ads when exposed but visit the promoted website or conduct campaign-related searches later. Online panels that unobtrusively collect panelists' Web behavior data and link ad exposure to website visits and searches can more reliably assess the impact of digital ad exposure. From March to June 2012, the Centers for Disease Control and Prevention aired the national Tips From Former Smokers (Tips 2012) media campaign designed to encourage current smokers to quit. Advertisements ran across media channels, and the digital ads directed users to the Tips 2012 campaign website. OBJECTIVE: Our aim was to examine whether exposure to Tips 2012 digital ads influenced information-seeking behaviors online. METHODS: ComScore mined its panelists' Web behavior data for unique codes that would indicate exposure to Tips 2012 ads, regardless of whether panelists clicked the ad or not. A total of 15,319 US adults were identified as having been exposed to a Tips 2012 campaign ad. An equal number of unexposed adults (N=15,319) were identified and matched on demographics and Internet use behavior to the exposed group. Panelists' Web behavior data were mined for up to 4 weeks after initial Tips 2012 ad exposure to determine whether they visited the Tips 2012 campaign website or other cessation-related websites (eg, nicotine replacement therapy site) or conducted searches for campaign-related topics (eg, quit smoking). RESULTS: The proportion of exposed adults visiting the Tips 2012 sites increased from 0.4% in Week 1 to 0.9% 4 weeks after ad exposure, and these rates were significantly higher than in the unexposed group (0.1% in Week 1 to 0.4% in Week 4, P<.001) across all weeks examined. The proportion of exposed panelists visiting other cessation websites increased from 0.2% in Week 1 to 0.3% 4 weeks after initial ad exposure, and these rates were significantly higher than in the unexposed group (0.0% in Week 1 to 0.2% in Week 4, P=.001 to P=.019) across all weeks examined. There were no significant differences in searches for campaign-related topics between the exposed and unexposed group during most of the weeks examined. CONCLUSIONS: These results suggest that online ad exposure is associated with confirmed visits to the Tips 2012 campaign sites and visits to other cessation websites and that these information-seeking behaviors occur up to several weeks after ad exposure. Web behavior data from online panels are useful for examining exposure and behavioral responses to digital campaign ads.


Assuntos
Publicidade , Promoção da Saúde , Comportamento de Busca de Informação , Internet , Abandono do Hábito de Fumar , Fumar/terapia , Adolescente , Adulto , Idoso , Centers for Disease Control and Prevention, U.S. , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos , Adulto Jovem
8.
BMC Public Health ; 15: 1136, 2015 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26572610

RESUMO

BACKGROUND: Literature suggests that Americans may have higher levels of perceived threat to Ebola than are warranted. METHODS: We surveyed 1018 U.S. adults from a nationally representative Internet panel about their knowledge, perceived threat, and behavioral intentions during the 2014 Ebola outbreak. RESULTS: Eighty-six percent of respondents knew that Ebola could be transmitted through blood and bodily fluids. However, a large percentage had some inaccurate knowledge and 19 % believed Ebola would spread to the U.S. Respondents favored mandatory quarantine (63 %) and travel bans (55 %). Confidence in the ability of the media and government to accurately report on or prevent a U.S. epidemic was low. Fifty-two percent intended to engage in behaviors such as avoiding public transportation. DISCUSSION: Despite low perceived susceptibility, half intended to engage in behaviors to prevent transmission and large numbers favored policies not currently recommended by health officials. The extreme nature of Ebola virus likely motivated people to engage in behaviors and favor policies that were not necessary given the low risk of transmission in the U.S. CONCLUSIONS: Health officials should ensure the public has accurate information about Ebola and bolster confidence in the government's ability to control infectious diseases in case of a future outbreak in the U.S.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Doença pelo Vírus Ebola/prevenção & controle , Doença pelo Vírus Ebola/psicologia , Adolescente , Adulto , Feminino , Doença pelo Vírus Ebola/transmissão , Humanos , Internet , Masculino , Meios de Comunicação de Massa , Pessoa de Meia-Idade , Quarentena , Viagem , Estados Unidos , Adulto Jovem
9.
J Med Internet Res ; 17(11): e251, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26545927

RESUMO

BACKGROUND: Marketing and use of electronic cigarettes (e-cigarettes) and other electronic nicotine delivery devices have increased exponentially in recent years fueled, in part, by marketing and word-of-mouth communications via social media platforms, such as Twitter. OBJECTIVE: This study examines Twitter posts about e-cigarettes between 2008 and 2013 to gain insights into (1) marketing trends for selling and promoting e-cigarettes and (2) locations where people use e-cigarettes. METHODS: We used keywords to gather tweets about e-cigarettes between July 1, 2008 and February 28, 2013. A randomly selected subset of tweets was manually coded as advertising (eg, marketing, advertising, sales, promotion) or nonadvertising (eg, individual users, consumers), and classification algorithms were trained to code the remaining data into these 2 categories. A combination of manual coding and natural language processing methods was used to indicate locations where people used e-cigarettes. Additional metadata were used to generate insights about users who tweeted most frequently about e-cigarettes. RESULTS: We identified approximately 1.7 million tweets about e-cigarettes between 2008 and 2013, with the majority of these tweets being advertising (93.43%, 1,559,508/1,669,123). Tweets about e-cigarettes increased more than tenfold between 2009 and 2010, suggesting a rapid increase in the popularity of e-cigarettes and marketing efforts. The Twitter handles tweeting most frequently about e-cigarettes were a mixture of e-cigarette brands, affiliate marketers, and resellers of e-cigarette products. Of the 471 e-cigarette tweets mentioning a specific place, most mentioned e-cigarette use in class (39.1%, 184/471) followed by home/room/bed (12.5%, 59/471), school (12.1%, 57/471), in public (8.7%, 41/471), the bathroom (5.7%, 27/471), and at work (4.5%, 21/471). CONCLUSIONS: Twitter is being used to promote e-cigarettes by different types of entities and the online marketplace is more diverse than offline product offerings and advertising strategies. E-cigarettes are also being used in public places, such as schools, underscoring the need for education and enforcement of policies banning e-cigarette use in public places. Twitter data can provide new insights on e-cigarettes to help inform future research, regulations, surveillance, and enforcement efforts.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina/tendências , Internet/estatística & dados numéricos , Marketing/tendências , Mídias Sociais/tendências , Humanos
10.
J Community Health ; 39(4): 800-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24515948

RESUMO

An estimated 43.5 million American adults currently smoke cigarettes. Well-designed tobacco education campaigns with adequate reach increase cessation and reduce tobacco use. Smokers report great interest in quitting but few use effective treatments including quitlines (QLs). This review examined traditional (TV, radio, print ads) versus innovative tobacco cessation (internet, social media) promotions for QL services. Between November 2011 and January 2012, searches were conducted on EBSCO, PubMed, Wilson, OCLC, CQ Press, Google Scholar, Gale, LexisNexis, and JSTOR. Existing literature shows that the amount of radio and print advertising, and promotion of free cessation medications increases QL call volume. Television advertising volume seems to be the best predictor of QL service awareness. Much of the literature on Internet advertising compares the characteristics of participants recruited for studies through various channels. The majority of the papers indicated that Internet-recruited participants were younger; this was the only demographic characteristic with high agreement across studies. Traditional media was only studied within mass media campaigns with TV ads having a consistent impact on increasing calls to QLs, therefore, it is hard to distinguish the impact of traditional media as an independent QL promotion intervention. With innovative media, while many QL services have a presence on social media sites, there is no literature on evaluating the effectiveness of these channels for quitline promotion.


Assuntos
Informação de Saúde ao Consumidor/métodos , Promoção da Saúde/métodos , Linhas Diretas , Marketing de Serviços de Saúde/métodos , Abandono do Hábito de Fumar/métodos , Fumar/epidemiologia , Adulto , Publicidade , Bases de Dados Bibliográficas , Promoção da Saúde/tendências , Humanos , Internet , Meios de Comunicação de Massa , Inovação Organizacional , Prevenção do Hábito de Fumar , Mídias Sociais , Estados Unidos/epidemiologia
11.
J Med Internet Res ; 16(7): e169, 2014 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-25014311

RESUMO

BACKGROUND: The promotion of evidence-based cessation services through social media sites may increase their utilization by smokers. Data on social media adoption and use within tobacco control programs (TCPs) have not been reported. OBJECTIVE: This study examines TCP use of and activity levels on social media, the reach of TCP sites, and the level of engagement with the content on sites. METHODS: A cross-sectional descriptive study of state TCP social media sites and their content was conducted. RESULTS: In 2013, 60% (30/50) of TCPs were using social media. Approximately one-quarter (26%, 13/50) of all TCPs used 3 or more social media sites, 24% (12/50) used 2, and 10% (5/50) used 1 site. Overall, 60% (30/50) had a Facebook page, 36% (18/50) had a Twitter page, and 40% (20/50) had a YouTube channel. The reach of social media was different across each site and varied widely by state. Among TCPs with a Facebook page, 73% (22/30) had less than 100 likes per 100,000 adults in the state, and 13% (4/30) had more than 400 likes per 100,000 adults. Among TCPs with a Twitter page, 61% (11/18) had less than 10 followers per 100,000 adults, and just 1 state had more than 100 followers per 100,000 adults. Seven states (23%, 7/30) updated their social media sites daily. The most frequent social media activities focused on the dissemination of information rather than interaction with site users. Social media resources from a national cessation media campaign were promoted infrequently. CONCLUSIONS: The current reach of state TCP social media sites is low and most TCPs are not promoting existing cessation services or capitalizing on social media's interactive potential. TCPs should create an online environment that increases participation and 2-way communication with smokers to promote free cessation services.


Assuntos
Promoção da Saúde/métodos , Abandono do Hábito de Fumar/métodos , Prevenção do Hábito de Fumar , Mídias Sociais , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Governo Estadual , Tabagismo/prevenção & controle , Estados Unidos
12.
PLoS One ; 19(5): e0299698, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38722993

RESUMO

Misophonia, a heightened aversion to certain sounds, turns common cognitive and social exercises (e.g., paying attention during a lecture near a pen-clicking classmate, coexisting at the dinner table with a food-chomping relative) into challenging endeavors. How does exposure to triggering sounds impact cognitive and social judgments? We investigated this question in a sample of 65 participants (26 misophonia, 39 control) from the general population. In Phase 1, participants saw faces paired with auditory stimuli while completing a gender judgment task, then reported sound discomfort and identification. In Phase 2, participants saw these same faces with novel ones and reported face likeability and memory. For both oral and non-oral triggers, misophonic participants gave higher discomfort ratings than controls did-especially when identification was correct-and performed slower on the gender judgment. Misophonic participants rated lower likeability than controls did for faces they remembered with high discomfort sounds, and face memory was worse overall for faces originally paired with high discomfort sounds. Altogether, these results suggest that misophonic individuals show impairments on social and cognitive judgments if they must endure discomforting sounds. This experiment helps us better understand the day-to-day impact of misophonia and encourages usage of individualized triggers in future studies.


Assuntos
Cognição , Julgamento , Humanos , Masculino , Feminino , Cognição/fisiologia , Adulto , Adulto Jovem , Estimulação Acústica , Memória/fisiologia
13.
Atten Percept Psychophys ; 86(4): 1163-1175, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38658517

RESUMO

People tend to employ suboptimal attention control strategies during visual search. Here we question why people are suboptimal, specifically investigating how knowledge of the optimal strategies and the time available to apply such strategies affect strategy use. We used the Adaptive Choice Visual Search (ACVS), a task designed to assess attentional control optimality. We used explicit strategy instructions to manipulate explicit strategy knowledge, and we used display previews to manipulate time to apply the strategies. In the first two experiments, the strategy instructions increased optimality. However, the preview manipulation did not significantly boost optimality for participants who did not receive strategy instruction. Finally, in Experiments 3A and 3B, we jointly manipulated preview and instruction with a larger sample size. Preview and instruction both produced significant main effects; furthermore, they interacted significantly, such that the beneficial effect of instructions emerged with greater preview time. Taken together, these results have important implications for understanding the strategic use of attentional control. Individuals with explicit knowledge of the optimal strategy are more likely to exploit relevant information in their visual environment, but only to the extent that they have the time to do so.


Assuntos
Atenção , Reconhecimento Visual de Modelos , Tempo de Reação , Humanos , Reconhecimento Visual de Modelos/fisiologia , Orientação , Comportamento de Escolha , Adulto Jovem , Feminino , Masculino
14.
bioRxiv ; 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38559074

RESUMO

Phosphofructokinase-1 (PFK1) catalyzes the rate-limiting step of glycolysis, committing glucose to conversion into cellular energy. PFK1 is highly regulated to respond to the changing energy needs of the cell. In bacteria, the structural basis of PFK1 regulation is a textbook example of allostery; molecular signals of low and high cellular energy promote transition between an active R-state and inactive T-state conformation, respectively Little is known, however, about the structural basis for regulation of eukaryotic PFK1. Here, we determine structures of the human liver isoform of PFK1 (PFKL) in the R- and T-state by cryoEM, providing insight into eukaryotic PFK1 allosteric regulatory mechanisms. The T-state structure reveals conformational differences between the bacterial and eukaryotic enzyme, the mechanisms of allosteric inhibition by ATP binding at multiple sites, and an autoinhibitory role of the C-terminus in stabilizing the T-state. We also determine structures of PFKL filaments that define the mechanism of higher-order assembly and demonstrate that these structures are necessary for higher-order assembly of PFKL in cells.

15.
Nat Commun ; 15(1): 7323, 2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-39183237

RESUMO

Phosphofructokinase-1 (PFK1) catalyzes the rate-limiting step of glycolysis, committing glucose to conversion into cellular energy. PFK1 is highly regulated to respond to the changing energy needs of the cell. In bacteria, the structural basis of PFK1 regulation is a textbook example of allostery; molecular signals of low and high cellular energy promote transition between an active R-state and inactive T-state conformation, respectively. Little is known, however, about the structural basis for regulation of eukaryotic PFK1. Here, we determine structures of the human liver isoform of PFK1 (PFKL) in the R- and T-state by cryoEM, providing insight into eukaryotic PFK1 allosteric regulatory mechanisms. The T-state structure reveals conformational differences between the bacterial and eukaryotic enzyme, the mechanisms of allosteric inhibition by ATP binding at multiple sites, and an autoinhibitory role of the C-terminus in stabilizing the T-state. We also determine structures of PFKL filaments that define the mechanism of higher-order assembly and demonstrate that these structures are necessary for higher-order assembly of PFKL in cells.


Assuntos
Trifosfato de Adenosina , Fosfofrutoquinase-1 , Humanos , Trifosfato de Adenosina/metabolismo , Regulação Alostérica , Microscopia Crioeletrônica , Glicólise , Fígado/enzimologia , Fígado/metabolismo , Modelos Moleculares , Fosfofrutoquinase-1/metabolismo , Fosfofrutoquinase-1/química , Fosfofrutoquinase-1/genética , Conformação Proteica
16.
Pers Soc Psychol Bull ; 49(12): 1663-1678, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36062325

RESUMO

What does it mean to be in solitude? Researchers building this nascent field are learning much about the potential affordances of solitude, but lack an agreed-upon definition or set of definitions. Arriving at that meaning is crucial to forming a solid foundation for studies that use both naturalistic and laboratory designs to explore outcomes of solitude. This study identified themes from semi-structured interviews with adults aged 19 to 80 from diverse backgrounds. We concluded that solitude is a state in which the dominant relationship is with the self. If not physically alone, people in solitude are mentally distanced from others and away from active technology-mediated interactions. Complete solitude involves both physical separation and inner focus, but solitude is best defined through a taxonomy that recognizes physical separation and internal focus as independent, sufficient characteristics. An internal focus benefits from (but is not defined by) balancing solitude with social time, quiet, and choice.


Assuntos
Distância Psicológica , Adulto , Humanos , Adulto Jovem , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais
17.
Front Neurosci ; 16: 880759, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36017175

RESUMO

Misophonia, an extreme aversion to certain environmental sounds, is a highly prevalent yet understudied condition plaguing roughly 20% of the general population. Although neuroimaging research on misophonia is scant, recent work showing higher resting-state functional connectivity (rs-fMRI) between auditory cortex and orofacial motor cortex in misophonia vs. controls has led researchers to speculate that misophonia is caused by orofacial mirror neurons. Since orofacial motor cortex was defined using rs-fMRI, we attempted to theoretically replicate these findings using orofacial cortex defined by task-based fMRI instead. Further, given our recent work showing that a wide variety of sounds can be triggering (i.e., not just oral/nasal sounds), we investigated whether there is any neural evidence for misophonic aversion to non-orofacial stimuli. Sampling 19 adults with varying misophonia from the community, we collected resting state data and an fMRI task involving phoneme articulation and finger-tapping. We first defined "orofacial" cortex in each participant using rs-fMRI as done previously, producing what we call resting-state regions of interest (rsROIs). Additionally, we functionally defined regions (fROIs) representing "orofacial" or "finger" cortex using phoneme or finger-tapping activation from the fMRI task, respectively. To investigate the motor specificity of connectivity differences, we subdivided the rsROIs and fROIs into separate sensorimotor areas based on their overlap with two common atlases. We then calculated rs-fMRI between each rsROI/fROI and a priori non-sensorimotor ROIs. We found increased connectivity in mild misophonia between rsROIs and both auditory cortex and insula, theoretically replicating previous results, with differences extending across multiple sensorimotor regions. However, the orofacial task-based fROIs did not show this pattern, suggesting the "orofacial" cortex described previously was not capturing true orofacial cortex; in fact, using task-based fMRI evidence, we find no selectivity to orofacial action in these previously described "orofacial" regions. Instead, we observed higher connectivity between finger fROIs and insula in mild misophonia, demonstrating neural evidence for non-orofacial triggers. These results provide support for a neural representation of misophonia beyond merely an orofacial/motor origin, leading to important implications for the conceptualization and treatment of misophonia.

18.
R I Med J (2013) ; 105(8): 53-56, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36173912

RESUMO

INTRODUCTION: The purpose of this study was to evaluate the accuracy of visual joint angle assessments by orthopaedic surgery trainees amongst various levels of training. METHODS: Sagittal plane photographs of several joints at various angles were distributed to trainees within an orthopaedic residency program. Joint angles were estimated and compared to those obtained with a goniometer. Inter-and intra-rater reliability and ANOVA were conducted to assess differences between groups. RESULTS: Twenty trainees were studied. The percent error for knee measurements differed at 23.1%, 26.2% and 11.1% for the PGY 2-3, PGY 4-5 and PGY 6 groups, respectively (P=0.024). Percentage error for ankles showed the greatest variability at 69.7-96.3%. Intra-rater reliabilities for all visual joint angle assessment were similar amongst groups. CONCLUSIONS: Visual joint angle assessments vary amongst trainees, with PGY 6s most accurately identifying knee joint angles. Visual assessment is inaccurate compared to goniometric measurements, thus limiting visual measurements during patient encounters.


Assuntos
Procedimentos Ortopédicos , Ortopedia , Humanos , Articulação do Joelho , Reprodutibilidade dos Testes
20.
Front Psychol ; 12: 714518, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34790144

RESUMO

Solitude - the state of being alone and not physically with another - can be rewarding. The present research explored the potential benefits of solitude from a pragmatist approach: a ground-up, top-down perspective that is receptive to new knowledge but informed by theory. Participant recruitment was stratified by age and gender, and the sample involved 2,035 individuals including adolescents (13-16 years), adults (35-55 years), or older adults (65+ years). Data were analyzed with a mixed-methods approach. Coded themes from brief narratives about solitude were extracted, and their frequencies (i.e., their salience to participants) were compared across the lifespan. Themes were then correlated with two indicators of well-being in solitude: self-determined motivation for solitude and peaceful mood. Several prominent themes emerged when talking about time spent in solitude. With the exception of feeling competent in solitude, which was described frequently but consistently unrelated to self-reported well-being regardless of age, benefits of solitude tended to shift over the lifespan. Some qualities, such as a sense of autonomy (self-connection and reliance; absence of pressure), were salient and consequential for everyone, but increasingly so from adolescence to older adulthood. Older adults also reported feeling most peaceful in solitude and described their social connection and alienation less frequently, suggesting they see solitude and social time as more distinct states. Findings are discussed in light of existing work on solitude across the lifespan, and theoretical frameworks that spoke well to the data (e.g., self-determination theory).

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