RESUMO
Many powered prosthetic devices use load cells to detect ground interaction forces and gait events. These sensors introduce additional weight and cost in the device. Recent proprioceptive actuators enable an algebraic relationship between actuator torques and ground contact forces. This paper presents a proprioceptive force sensing paradigm which estimates ground reaction forces as a solution to detect gait events without a load cell. A floating body dynamic model is obtained with constraints at the center of pressure representing foot-ground interaction. Constraint forces are derived to estimate ground reaction forces and subsequently timing of gait events. A treadmill experiment is conducted with a powered knee-ankle prosthesis used by an able-bodied subject walking at various speeds and slopes. Results show accurate gait event timing, with pooled data showing heel strike detection lagging by only 6.7 ± 7.2 ms and toe off detection leading by 30.4 ± 11.0 ms compared to values obtained from the load cell. These results establish proof of concept for predicting gait events without a load cell in powered prostheses with proprioceptive actuators.
RESUMO
Background: Hands-on culinary medicine education for medical trainees has emerged as a promising tool for cardiovascular health promotion. Purpose: To determine whether virtual culinary medicine programming associates with Mediterranean diet (MedDiet) adherence and lifestyle medicine competencies among medical trainees across the USA. Method: A total of 1433 medical trainees across 19 sites over a 12-month period were included. The Cooking for Health Optimisation with Patients-Medical Trainees survey composed of 61 questions regarding demographics, nutritional attitudes, dietary habits including MedDiet score and lifestyle medicine counselling competencies. Multivariable logistic regression assessed the association of virtual culinary medicine education with MedDiet intake and nutritional attitudes. Results: There were 519 medical trainees who participated in virtual culinary medicine education and 914 medical trainees who participated in their standard nutrition curricula. More than one-half of participants were women (n=759) and the mean age was 27 years old. Compared with students enrolled in traditional nutrition curricula, participants in virtual culinary medicine education were 37% more likely to adhere to MedDiet guidelines for fruit intake (OR 1.37, 95% CI 1.03 to 1.83, p=0.03). Virtual culinary medicine education was associated with higher proficiency in lifestyle medicine counselling categories, notably recommendations involving fibre (OR 4.03; 95% CI 3.05 to 5.34), type 2 diabetes prevention (OR 4.69; 95% CI 3.51 to 6.27) and omega fatty acids (OR 5.21; 95% CI 3.87 to 7.02). Virtual culinary medicine education had a similar, although higher magnitude association with MedDiet counselling competency (OR 5.73, 95% CI 4.26 to 7.70) when compared with historical data previously reported using hands-on, in-person culinary medicine courseware (OR 4.97, 95% CI 3.89 to 6.36). Conclusions: Compared with traditional nutritional educational curricula, virtual culinary medicine education is associated with higher MedDiet adherence and lifestyle medicine counselling competencies among medical trainees. Both virtual and hands-on culinary medicine education may be useful for cardiovascular health promotion.
RESUMO
OBJECTIVE: Combat-exposed veterans risk encountering events that disrupt beliefs. To facilitate reduced discrepancy between prior beliefs and current trauma appraisals, veterans may engage in a process of meaning-making. Meaning-making can lead to positive outcomes, such as integrating the traumatic event into one's life narrative or adapting global meaning (meaning made) or elicit distress. Given these potentially different outcomes, this study examined potential correlates of posttraumatic stress symptom (PTSS) severity and meaning made, including relationship attachment dimensions of anxiety and avoidance, and difficulties with emotion regulation, while controlling for combat exposure. METHOD: Veterans receiving mental health services at a Veterans Affairs (VA) Medical Center and a VA community-based outpatient clinic (N = 130) completed measures through a paper-and-pencil survey. Almost all participants (92%) were male, with a mean age of 55.92 years. RESULTS: In terms of meaning made, lower levels of attachment anxiety and emotional clarity (an aspect of emotion regulation) predicted higher meaning made. In terms of PTSS severity, higher attachment avoidance, attachment anxiety, and difficulties engaging in goal-directed behavior (an aspect of emotion regulation) significantly predicted higher PTSS severity. CONCLUSION: Aspects of both attachment style and emotion regulation difficulties affect meaning made and PTSS severity. These constructs may be especially relevant for clinicians working with veterans to help PTSS and support meaning made postcombat.
Assuntos
Transtornos de Estresse Pós-Traumáticos , Veteranos , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Veteranos/psicologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Ansiedade , Emoções , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: Rural areas in the Southern United States are characterized by certain cultural values that may delay or prevent mental health service utilization. The present study examined a four-stage chain of serial mediation where higher levels of general self-reliance would be related to greater levels of public stigma, which would in turn be related to higher levels of self-stigma, followed by greater self-reliance about managing mental health problems, and finally, more negative attitudes toward seeking help from psychologists. METHOD: Community members who lived in rural counties in the Southern United States (N = 783) completed measures of these constructs online. RESULTS: Mediation analyses supported a direct association between general self-reliance and attitudes toward help-seeking that was explained in serial by higher levels of public stigma, self-stigma, and mental health self-reliance. CONCLUSIONS: Clinical implications for rural practitioners are suggested including instilling policy changes, increasing provider visibility, and addressing barriers in therapy.
Assuntos
Transtornos Mentais , Serviços de Saúde Mental , Humanos , Análise de Mediação , Transtornos Mentais/psicologia , Transtornos Mentais/terapia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Estigma SocialRESUMO
The delivery of safe, visible wavelengths of light can be an effective, pathogen-agnostic, countermeasure that would expand the current portfolio of SARS-CoV-2 intervention strategies beyond the conventional approaches of vaccine, antibody, and antiviral therapeutics. Employing custom biological light units, that incorporate optically engineered light-emitting diode (LED) arrays, we harnessed monochromatic wavelengths of light for uniform delivery across biological surfaces. We demonstrated that primary 3D human tracheal/bronchial-derived epithelial tissues tolerated high doses of a narrow spectral band of visible light centered at a peak wavelength of 425 nm. We extended these studies to Vero E6 cells to understand how light may influence the viability of a mammalian cell line conventionally used for assaying SARS-CoV-2. The exposure of single-cell monolayers of Vero E6 cells to similar doses of 425 nm blue light resulted in viabilities that were dependent on dose and cell density. Doses of 425 nm blue light that are well-tolerated by Vero E6 cells also inhibited infection and replication of cell-associated SARS-CoV-2 by > 99% 24 h post-infection after a single five-minute light exposure. Moreover, the 425 nm blue light inactivated cell-free betacoronaviruses including SARS-CoV-1, MERS-CoV, and SARS-CoV-2 up to 99.99% in a dose-dependent manner. Importantly, clinically applicable doses of 425 nm blue light dramatically inhibited SARS-CoV-2 infection and replication in primary human 3D tracheal/bronchial tissue. Safe doses of visible light should be considered part of the strategic portfolio for the development of SARS-CoV-2 therapeutic countermeasures to mitigate coronavirus disease 2019 (COVID-19).
Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19/prevenção & controle , Luz , SARS-CoV-2 , Traqueia/efeitos da radiação , Replicação Viral/efeitos da radiação , Adulto , Animais , Antivirais/farmacologia , Brônquios , Calibragem , Sistema Livre de Células , Chlorocebus aethiops , Epitélio/patologia , Feminino , Humanos , Mucosa Respiratória/efeitos da radiação , Traqueia/virologia , Células VeroRESUMO
METHODS: Adults seeking behavioral health or medical treatment (N = 158) were recruited from a community healthcare agency and a residential support program in the southeastern United States. RESULTS: Individuals who reported interpersonal trauma had significantly higher total PTS severity and symptom clusters. No significant difference was found in perceived PTG based on trauma type. No significant curvilinear relationship between PTS and perceived PTG was found. A significant negative linear relationship was observed between PTS and perceived PTG for non-interpersonal trauma, but not interpersonal trauma. CONCLUSION: Trauma type may influence the PTS and perceived PTG relationship and, while associated with PTS, seems less important to reporting of perceived PTG.
Assuntos
Crescimento Psicológico Pós-Traumático , Transtornos de Estresse Pós-Traumáticos , Adaptação Psicológica , Adulto , Humanos , Sudeste dos Estados UnidosRESUMO
AIM: To develop a device to aid in insertion and removal of dentures in patients with limited range of motion. CASE REPORT: A 62-year-old male with congenital musculoskeletal system anomaly, severe scoliosis, missing teeth, and poor dentition presented for comprehensive dental care. Patient had significant range of motion limitations resulting in an inability to reach his mouth. A device allowing for independent insertion, removal, and cleaning of dentures was made for patient. Dentures were fabricated and scanned using an intraoral scanner, traditional surgical guide for implant placement was adapted to accommodate neodynium magnets and wooden dowel, and guide was 3D printed. Stainless steel spheres were processed into denture to correspond to magnets in guide. Patient demonstrated ability to independently insert and remove both his maxillary complete denture and mandibular partial denture using device. CONCLUSION: A successful device for insertion and removal of complete and partial dentures can be fabricated by adapting a surgical guide to incorporate magnets by processing stainless steel spheres into the dentures. This device could be helpful for any individuals demonstrating musculoskeletal system anomalies or range of motion deficits.
Assuntos
Prótese Total , Mandíbula , Humanos , Masculino , Maxila , Pessoa de Meia-Idade , Amplitude de Movimento ArticularRESUMO
We describe the case of a child with progressive abdominal pain and rash admitted to a large tertiary children's hospital in the Chicago metropolitan area and subsequently found to have immunoglobulin A (IgA) vasculitis and coronavirus disease 2019 (COVID-19). This patient presented with abdominal pain, purpuric lesions, hematochezia, increasingly elevated D-dimer, and abnormal inflammatory markers on laboratory evaluation. To the best of our knowledge, this article describes the only reported pediatric case of COVID-19 associated with IgA vasculitis. [Pediatr Ann. 2021;50(1):e44-e48.].
Assuntos
COVID-19/diagnóstico , Vasculite por IgA/diagnóstico , Imunoglobulina A , Dor Abdominal/etiologia , Proteína C-Reativa/análise , Pré-Escolar , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Fibrinolíticos/uso terapêutico , Hemorragia Gastrointestinal/etiologia , Glucocorticoides/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Vasculite por IgA/tratamento farmacológico , MasculinoRESUMO
Nanoparticle (NP) use can increase biological activity and adversely impact the environment. This study was the first to quantify biogas increases with NP mixtures during continuous anaerobic digestion (AD) of poultry litter and NP uptake in crops through tracking: 1) CH4 and H2S production from a NP mixture (Fe, Ni, and Co) in 30 L continuous digester (AD1) for 278 days compared to a control digester (AD2) without NP addition, 2) NP degradation during digestion, 3) using AD effluent with and without NP addition as a fertilizer, and 4) plant uptake of NPs. With NP inclusion, CH4 production increased by 23.7%, and H2S was reduced by 56.3%. The AD1 effluent had 1,160-19,400% higher NP concentrations and the lettuce biomass had 21.0-1,920% more NPs than lettuce fertilized with the AD2 effluent. This study showed that the effects of NPs remaining in the AD effluent must be considered.
Assuntos
Reatores Biológicos , Nanopartículas Metálicas , Anaerobiose , Animais , Biocombustíveis , Fertilizantes , MetanoRESUMO
Although rurality is often treated as an aspect of diversity, researchers disagree regarding whether the traditional rural values of self-reliance, distrust of outsiders, religiosity, centrality of family, and fatalism continue to differentiate rural versus urban undergraduates. The present study examined 1) whether differences in these values exist between rural and urban college students in the United States and 2) whether these rural values might mediate the association between geographic remoteness and posttraumatic stress symptom (PTSS) severity. College undergraduates in the United States who reported experiencing traumatic and/or stressful events (N = 213) completed measures of these constructs through an online survey. T-test results indicated that rural respondents had significantly higher levels of PTSS severity and distrust of outsiders and significantly lower levels of religiosity when compared with urban participants. After controlling for gender, distrust of outsiders and religiosity also emerged as significant mediators of the relationship between geographic remoteness and PTSS severity. Thus, despite research that highlights differences based on geographic location, similarities and differences exist for rural and urban undergraduates in the United States with regard to traditionally rural values. For rural undergraduate clients presenting with trauma symptoms, our results suggest that building trust and religious and/or spiritual self-care may be particularly critical.
Assuntos
População Rural/estatística & dados numéricos , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Estudantes/psicologia , População Urbana/estatística & dados numéricos , Adolescente , Características Culturais , Feminino , Humanos , Masculino , Religião , Autocuidado/psicologia , Índice de Gravidade de Doença , Estudantes/classificação , Estados Unidos/epidemiologia , Adulto JovemRESUMO
OBJECTIVE: After combat, veterans may experience mental health symptomology and attempt to make meaning from their experiences. The present study qualitatively examined the mental health effects of deployment and meaning-making among Operation Iraqi Freedom (OIF) or Operation Enduring Freedom (OEF) veterans. METHOD: OIF/OEF veterans who were exposed to combat (N = 14) participated in semi-structured interviews to assess how their perspectives had changed post-deployment. Most participants (86%) were male, with a mean age of 30. RESULTS: Veterans described issues post-combat that caused psychological distress or promoted distancing from others. Veterans also discussed factors that could promote or hinder meaning-making, including perceptions of growth, changed global beliefs, and disillusionment. Finally, veterans described psychological reactions to death, which could be related to moral injury. CONCLUSION: Mental health concerns, meaning-making, and consideration of mortality appear to characterize veterans' experiences post-deployment. These constructs may be important for clinicians to consider when working with OIF/OEF veterans.
Assuntos
Campanha Afegã de 2001- , Guerra do Iraque 2003-2011 , Transtornos Mentais/psicologia , Destacamento Militar/psicologia , Veteranos/psicologia , Adulto , Feminino , Humanos , Masculino , Pesquisa Qualitativa , Veteranos/estatística & dados numéricosRESUMO
The syntheses, properties, and broad utility of noble metal plasmonic nanomaterials are now well-established. To capitalize on this exceptional utility, mitigate its cost, and potentially expand it, non-noble metal plasmonic materials have become a topic of widespread interest. As new plasmonic materials come online, it is important to understand and assess their ability to generate comparable or complementary plasmonic properties to their noble metal counterparts, including as both sensing and photoredox materials. Here, we study plasmon-driven chemistry on degenerately doped copper selenide (Cu2- xSe) nanoparticles. In particular, we observe plasmon-driven dimerization of 4-nitrobenzenethiol to 4,4'-dimercaptoazobenzene on Cu2- xSe surfaces with yields comparable to those observed from noble metal nanoparticles. Overall, our results indicate that doped semiconductor nanoparticles are promising for light-driven chemistry technologies.
RESUMO
Plasmonic materials show great potential for selective photocatalysis under relatively mild reaction conditions. However, the catalytic activity of these plasmonic catalysts can also depend upon the support material that stabilizes the catalysts, where the composition of the catalytic support may change the overall photocatalytic efficiency and yield. It is unknown how changes in the support material may change the plasmon-driven photocatalysis, which may be initiated by plasmon-derived hot carriers, localized heating, or enhanced electromagnetic fields. Herein, we probe the effects of catalytic supports on heating in plasmon-driven catalysis by examining various gold nanoparticle oxide systems. We use ultrafast surface-enhanced Raman thermometry to measure the effective temperature, equivalent to the vibrational kinetic energy, of reporter molecules located between plasmonic gold nanostructures and local environments ranging from ligands to mesoporous silica shells to silica shells. Upon photoexcitation, the transient effective temperature, equivalent to the energy deposited into a vibrational mode, of adsorbed molecules on the silica-coated samples increases, and the energy quickly dissipates within 3 ps. However, the baseline effective temperature that arises from the surface-enhanced Raman spectroscopy probing process depends upon the encapsulant, where the energy deposition differs by 200-300 K between the ligand-coated (citrate or CTAB) and the silica-coated samples. Adsorbates surrounded by a silica shell experience significantly higher effective temperatures than the adsorbates surrounded by ligands or solvent, likely because of the differing effective heat capacities of these media. Taken together, this work shows that a silica support impacts the localized heating of molecular adsorbates on the gold surface and may play a role in enhanced plasmonic photocatalysis because of increased thermal contributions.
RESUMO
Plasmonic materials efficiently convert light to various forms of energies for many applications, including photocatalysis, photovoltaics, and photothermal therapies. In particular, plasmonic photocatalysts hold incredible promise for highly selective sunlight-driven catalysis through the generation of highly energetic holes and electrons used to drive chemical reactions. However, plasmons are also known to generate heat, and the partitioning of photoexcitation energy into hot carriers and heat on molecularly relevant time scales is not well understood, yet plays a crucial role in designing and understanding these photocatalysts. Using an ultrafast surface-enhanced Raman thermometry technique, we probe the effective temperature, equivalent to the mode-specific increase of vibrational kinetic energy, of molecules adsorbed to gold nanoparticle aggregates in the most active hot spots on the picosecond time scale of chemical reactivity. This represents the first measurement of vibrational energy deposition for coupled molecular-plasmonic systems on the picosecond time scale of molecular motion. We find that upon plasmon excitation, the adsorbates in the hot spots undergo an initial energy transfer within several picoseconds that changes the effective temperature of the system by less than 100 K, even at peak flux values 108 times stronger than focused sunlight. The energy quickly dissipates from the adsorbates into the surroundings in less than 5 ps, even at the highest values of photoexcitation. This surprisingly modest energy transfer of the most active regions of the plasmonic materials on the ultrafast time scale decisively proves that most plasmonic photocatalysis is not primarily thermally driven.
RESUMO
Hot electrons generated through plasmonic excitations in metal nanostructures show great promise for efficiently driving chemical reactions with light. However, the lifetime, yield, and mechanism of action of plasmon-generated hot electrons involved in a given photocatalytic process are not well understood. Here, we develop ultrafast surface-enhanced Raman scattering (SERS) as a direct probe of plasmon-molecule interactions in the plasmon-catalyzed dimerization of 4-nitrobenzenethiol to p,p'-dimercaptoazobenzene. Ultrafast SERS probing of these molecular reporters in plasmonic hot spots reveals transient Fano resonances, which we attribute to near-field coupling of Stokes-shifted photons to hot electron-driven metal photoluminescence. Surprisingly, we find that hot spots that yield more photoluminescence are much more likely to drive the reaction, which indirectly proves that plasmon-generated hot electrons induce the photochemistry. These ultrafast SERS results provide insight into the relative reactivity of different plasmonic hot spot environments and quantify the ultrafast lifetime of hot electrons involved in plasmon-driven chemistry.
RESUMO
Ultrafast surface-enhanced Raman spectroscopy (SERS) with pico- and femtosecond time resolution has the ability to elucidate the mechanisms by which plasmons mediate chemical reactions. Here we review three important technological advances in these new methodologies, and discuss their prospects for applications in areas including plasmon-induced chemistry and sensing at very low limits of detection. Surface enhancement, arising from plasmonic materials, has been successfully incorporated with stimulated Raman techniques such as femtosecond stimulated Raman spectroscopy (FSRS) and coherent anti-Stokes Raman spectroscopy (CARS). These techniques are capable of time-resolved measurement on the femtosecond and picosecond time scale and can be used to follow the dynamics of molecules reacting near plasmonic surfaces. We discuss the potential application of ultrafast SERS techniques to probe plasmon-mediated processes, such as H2 dissociation and solar steam production. Additionally, we discuss the possibilities for high sensitivity SERS sensing using these stimulated Raman spectroscopies.
Assuntos
Abelhas , Hialuronoglucosaminidase/uso terapêutico , Hipersensibilidade/diagnóstico , Hipersensibilidade/tratamento farmacológico , Mordeduras e Picadas de Insetos/complicações , Adulto , Animais , Venenos de Abelha/classificação , Venenos de Abelha/imunologia , Humanos , Hipersensibilidade/classificação , Testes Intradérmicos/métodosRESUMO
Surface-enhanced Raman spectroscopy (SERS) is a promising technique for in vivo bioanalyte detection, but accurate characterization of SERS biosensors can be challenging due to difficulties in differentiating resonance and surface enhancement contributions to the Raman signal. Here, we quantitate the resonance Raman cross-sections for a commonly used near-infrared SERS dye, 3,3'-diethylthiatricarbocyanine (DTTC). It is typically challenging to measure resonance Raman cross-sections for fluorescent dye molecules due to the overwhelming isoenergetic fluorescence signal. To overcome this issue, we used etalon-based femtosecond stimulated Raman spectroscopy, which is intrinsically designed to acquire a stimulated Raman signal without strong fluorescence or interference from signals resulting from other four-wave mixing pathways. Using this technique, we found that the cross-sections for most of the resonantly enhanced modes in DTTC exceed 10(-25) cm(2)/molecule. These cross-sections lead to high signal magnitude SERS signals from even weakly enhancing SERS substrates, as much of what appears to be a SERS signal is actually coming from the intrinsically strong resonance Raman signal. Our work will lead to a more accurate determination of SERS enhancement factors and SERS substrate characterization in the biologically relevant near-infrared region, ultimately leading to a more widespread use of SERS for biosensing and bioimaging applications.