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3.
J Spinal Cord Med ; 46(1): 45-52, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-34505828

RESUMO

OBJECTIVE: The purpose of this study was to compare trunk mechanics, distance covered, and average instantaneous velocity and acceleration recorded with caregivers performing transfer tasks using a research mannequin with both a prototype robotic assisted transfer device (RATD) and a mobile floor lift. DESIGN: Cross-Sectional. SETTING: Biomechanics Lab and Human Engineering Research Laboratories. PARTICIPANTS: Caregivers (N = 21). INTERVENTION: Robotic Assisted Transfer Device. OUTCOME MEASURES: Range of flexion-extension, lateral bend, and axial rotation; distance covered; average instantaneous velocity and acceleration. RESULTS: Caregivers performing transfers using the RATD as compared to when using the moble floor lift reported significantly smaller range of trunk flexion-extension, lateral bending, and axial rotation, and reported lower pelvic based distance covered and slower average instantaneous velocity and acceleration (P < 0.001). CONCLUSION: The design and usability of a RATD indicates design driven mobility advantages over clinical standard mobile floor lifts due to its ability to expand the workspace while further reducing risk factors for low back pain. While the concept is promising, further testing is required to address limitations and confirm the concept for clinical applications.


Assuntos
Procedimentos Cirúrgicos Robóticos , Traumatismos da Medula Espinal , Humanos , Cuidadores , Estudos Transversais , Pelve , Fenômenos Biomecânicos
4.
Am J Phys Med Rehabil ; 101(6): 561-568, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35594407

RESUMO

BACKGROUND: The robotic assisted transfer device was developed as an updated lift technology to reduce adjustments in posture while increasing capabilities offered by transfer devices. The purpose of this study was to compare the trunk biomechanics of a robotic assisted transfer device and a mechanical floor lift in the transfer of a care recipient by a caregiver during essential transfer tasks. METHODS: Investigators enrolled 28 caregiver/care recipient dyads to complete 36 transferring tasks. Surface electromyography for the back muscles and motion data for trunk range of motion were collected for selected surfaces, phase, and direction tasks using a robotic assisted transfer device and a mechanical floor lift. RESULTS: Robotic assisted transfer device transfers required significantly smaller range of trunk flexion (P < 0.001), lateral bend (P < 0.001), and axial rotation (P = 0.01), in addition to smaller distance covered (P < 0.001), average instantaneous velocity (P = 0.01), and acceleration (P < 0.001) compared with a mobile floor lift. The robotic assisted transfer device transfers required significantly smaller peak erector spinae (left: P = 0.001; right: P < 0.001) and latissimus dorsi (right: P < 0.001) and integrated erector spinae left (P = 0.001) and latissimus dorsi right (P = 0.01) electromyography signals compared with the floor lift. CONCLUSIONS: The robotic assisted transfer device provides additional benefits to mobile floor lifts which, coupled with statistically lower flexion, extension, and rotation, may make them an appealing alternative intervention.


Assuntos
Procedimentos Cirúrgicos Robóticos , Cadeiras de Rodas , Cuidadores , Eletromiografia , Ergonomia , Humanos , Músculo Esquelético/fisiologia
5.
Disabil Rehabil Assist Technol ; 17(7): 833-839, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-32988254

RESUMO

INTRODUCTION: The RATD represents a novel methodology to reduce strain, manoeuvring, and cognitive load a caregiver experiences when conducting transfers on a mannequin. However, caregivers who used this new technology report suggested adjustments regarding the robot's human machine interface and shape as to improve transfer efficiency and comfort for care recipients. The purpose of this study was to test a redesigned RATD and compare its ergonomics during a transfer to those of a mechanical floor lift. METHODS: This was cross sectional protocol. As opposed to prior research which used a mannequin, caregivers in this study (N = 28) partnered with, and transferred, a mobility device user (N = 28) at three unique surfaces. Information about task demand and usability was collected from surveys after use of each device at each surface. RESULTS: Results indicated reduced physical demand (p = .004) and discomfort frequency (p = .01) in caregivers conducting the transfers with the RATD compared to the mechanical floor lift. Care recipients reported no significant differences between both transfer devices. Critiques with the interface, the harness and sling, and the robot's rigidity indicated more work is needed before introducing this technology to a larger market. Conclusions: The RATD represents a promising new intervention for transferring and handling care recipients who use wheelchairs. However, while caregivers report reduced physical demand and discomfort, more work is required to advance the ease of the human machine interface, the amount of space allowed for the robot to operate, and the ability of the care recipient to operate the technology independently.IMPLICATIONS FOR REHABILITATIONCaregivers report significant physical and mental stress while transferring clients in and out of a wheelchair.Clinical standard transfer equipment is limited in the space which it can be used.Robots, particularly those portable and powered, have the ability to not only make the transfer experience safer, but also expand the applications this equipment can provide.


Assuntos
Procedimentos Cirúrgicos Robóticos , Cadeiras de Rodas , Cuidadores , Estudos Transversais , Desenho de Equipamento , Humanos
6.
Molecules ; 26(21)2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34770741

RESUMO

The isothiourea-catalyzed enantioselective 1,6-conjugate addition of para-nitrophenyl esters to 2,6-disubstituted para-quinone methides is reported. para-Nitrophenoxide, generated in situ from initial N-acylation of the isothiourea by the para-nitrophenyl ester, is proposed to facilitate catalyst turnover in this transformation. A range of para-nitrophenyl ester products can be isolated, or derivatized in situ by addition of benzylamine to give amides at up to 99% yield. Although low diastereocontrol is observed, the diastereoisomeric ester products are separable and formed with high enantiocontrol (up to 94:6 er).

7.
Org Biomol Chem ; 19(16): 3620-3627, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33908571

RESUMO

The sequential acylative kinetic resolution (KR) of C2-symmetric (±)-1,2-syn and (±)-1,3-anti-diols using a packed bed microreactor loaded with the polystyrene-supported isothiourea, HyperBTM, is demonstrated in flow. The sequential KRs of C2-symmetric (±)-1,2-syn and (±)-1,3-anti-diols exploits Horeau amplification, with each composed of two successive KR processes, with each substrate class significantly differing in the relative rate constants for each KR process. Optimisation of the continuous flow set-up for both C2-symmetric (±)-1,2-syn and (±)-1,3-anti-diol substrate classes allowed isolation of reaction products in both high enantiopurity and yield. In addition to the successful KR of C2-symmetric (±)-1,2-syn and (±)-1,3-anti-diols, the application of this process to the more conceptually-complex scenario involving the sequential KR of C1-symmetric (±)-1,3-anti-diols was demonstrated, which involves eight independent rate constants.

8.
Mil Med ; 186(11-12): 1106-1114, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33538791

RESUMO

INTRODUCTION: Novel rehabilitation methods, including distribution and adoption of assistive technology for lower extremity impairments, are becoming crucial to ensure positive quality of life in all individuals. The quality of life of post-9/11 combat veterans is not well understood, in comparison to research on other populations. The following essay describes a review on health outcomes used to determine health-related quality of life (HR-QoL) among combat-injured service members who require mobility-related assistive technology. MATERIALS AND METHODS: Reviews pooled data from research on PubMed, EMBASE, CINAHL, and PsycINFO published after September 11, 2001, and included service members who sustained a mobility impairment because of involvement in a post-9/11 combat operation. Basic descriptors were extracted in addition to health outcomes used, which were then categorized and summarized by six domains for HR-QoL as defined by the World Health Organization. RESULTS: This review found health outcomes that fit in the pain and discomfort, negative emotions, mobility, social relations, access to and quality of healthcare services, and religious/spiritual/personal beliefs subdomains. The categorized results detailed their application to track and model HR-QoL health states in those with mobility impairments using mobility-based assistive technology. CONCLUSIONS: The research on combat-induced mobility impairments indicates assistive technology improves otherwise poor health states. The results model these domains and subdomains to determine overall HR-QoL and the quality of a healthcare intervention, though additional research is needed as only one study was identified to be experimental in design.


Assuntos
Tecnologia Assistiva , Veteranos , Humanos , Avaliação de Resultados em Cuidados de Saúde , Qualidade de Vida
9.
Disabil Rehabil Assist Technol ; 16(3): 270-279, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-31607186

RESUMO

OBJECTIVE: Novel developments in the robotics field have produced systems that can support person wheelchair transfers, maximize safety and reduce caregiver burden. The purpose of this study was to identify and describe these systems, their usability (or satisfaction), the context for which they have been or can be used and how they have been evaluated to determine evidence for their effectiveness. METHOD: Available research on Person Transfer Assist Systems (PTAS) was systematically gathered using similar standards to the PRISMA guidelines. The search terms were derived from common terms and via exploring similar review articles. Initial search terms displayed 1330 articles and by using the inclusion/exclusion criteria 96 articles were selected for abstract review. After full- text reviewing 48 articles were included. RESULTS: 29 articles concerned research in robotic transfer systems, 10 articles used both ceiling and floor-mounted lifts and 9 articles used only floor-mounted lifts as an intervention/control group. The results of this analysis identified a few usability evaluations for robotic transfer prototypes, especially ones comparing prototypes to existing marketed devices. CONCLUSION: Robotic device research is a recent development within assistive technology. Whilst usability evaluations provided evidence that a robotic device will provide better service to the user, the sample number of subjects used are minimal in comparison to any of the intervention/control group articles. Experimental studies between PTASs are required to support technological advancements. Caregiver injury risk has been the focus for most of the comparison articles; however, few articles focus on the implications to the person.IMPLICATIONS FOR REHABILITATIONCeiling mounted lifts are preferred over floor-based lifts due to lower injury rates.Many robotic transfer systems have been developed; however, there is a paucity of quantitative and qualitative studies.Based on the results of this review, rehabilitation settings are recommended to use ceiling over floor assist systems, and it is recommended to provide training on using devices to assist with patient transfers to lower the risk of injuries.


Assuntos
Desenho de Equipamento , Movimentação e Reposicionamento de Pacientes/instrumentação , Robótica/instrumentação , Tecnologia Assistiva , Cuidadores , Humanos , Cadeiras de Rodas , Ferimentos e Lesões/prevenção & controle
10.
Am J Phys Med Rehabil ; 100(9): 885-894, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-33315611

RESUMO

OBJECTIVE: The purpose of this study was to compare muscle activity in caregivers while using a novel robotic-assisted transfer device (Strong Arm) to a clinical standard of care (Hoyer Advance). DESIGN: A quasi-experimental design was used in which 20 caregivers (33 ± 15 yrs old) performed transfers with three surfaces (toilet, bench, and shower chair) with the Strong Arm and Hoyer Advance. Transfer completion time (seconds), peak percentage surface electromyography (EMG), and integrated EMG of the bilateral erector spinae, latissimus dorsi, pectoralis major and anterior deltoid were measured. RESULTS: Caregivers required less transfer time when transferring from wheelchair to surface using the Hoyer Advance (P = 0.011, f = 0.39). For the lower back, significantly lower peak percentage EMGs were found using Strong Arm in 50% and for the integrated EMG in 25% of the cases, with the remaining cases showing no significant differences. For the shoulder, significantly lower peak percentage EMG values were found using Strong Arm in 19% of transfers and lower integrated EMG was found in 25% of transfers when using the Hoyer Advance, with the remaining cases showing no significant differences. CONCLUSION: Although back muscle activation during Strong Arm transfers is statistically, but not clinically, lower, additional features that couple with significantly lower muscle activation make it an alternative to the clinical standard for further research and possible clinical applicability.


Assuntos
Cuidadores , Desenho de Equipamento , Movimentação e Reposicionamento de Pacientes/instrumentação , Músculo Esquelético/fisiologia , Saúde Ocupacional , Robótica , Adolescente , Adulto , Fenômenos Biomecânicos , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Beilstein J Org Chem ; 16: 1572-1578, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32704323

RESUMO

The N-heterocyclic carbene (NHC)-catalyzed formal [2 + 2] cycloaddition between α-aroyloxyaldehydes and trifluoroacetophenones, followed by ring opening with an amine or a reducing agent is described. The resulting ß-trifluoromethyl-ß-hydroxyamide and alcohol products are produced with reasonable diastereocontrol (typically ≈70:30 dr) and excellent enantioselectivity, and they can be isolated in moderate to good yield as a single diastereoisomer.

12.
Angew Chem Int Ed Engl ; 59(39): 17070-17076, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32542848

RESUMO

N,N,N',N'-Tetramethylethylenediamine (TMEDA) has been one of the most prevalent and successful additives used in iron catalysis, finding application in reactions as diverse as cross-coupling, C-H activation, and borylation. However, the role that TMEDA plays in these reactions remains largely undefined. Herein, studying the iron-catalyzed hydromagnesiation of styrene derivatives using TMEDA has provided molecular-level insight into the role of TMEDA in achieving effective catalysis. The key is the initial formation of TMEDA-iron(II)-alkyl species which undergo a controlled reduction to selectively form catalytically active styrene-stabilized iron(0)-alkyl complexes. While TMEDA is not bound to the catalytically active species, these active iron(0) complexes cannot be accessed in the absence of TMEDA. This mode of action, allowing for controlled reduction and access to iron(0) species, represents a new paradigm for the role of this important reaction additive in iron catalysis.


Assuntos
Alcenos/química , Etilenodiaminas/química , Compostos Ferrosos/síntese química , Ferro/química , Catálise , Compostos Ferrosos/química , Estrutura Molecular , Oxirredução
13.
Angew Chem Int Ed Engl ; 59(38): 16572-16578, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32491267

RESUMO

A highly enantioselective isothiourea-catalyzed acylative kinetic resolution (KR) of acyclic tertiary alcohols has been developed. Selectivity factors of up to 200 were achieved for the KR of tertiary alcohols bearing an adjacent ester substituent, with both reaction conversion and enantioselectivity found to be sensitive to the steric and electronic environment at the stereogenic tertiary carbinol centre. For more sterically congested alcohols, the use of a recently-developed isoselenourea catalyst was optimal, with equivalent enantioselectivity but higher conversion achieved in comparison to the isothiourea HyperBTM. Diastereomeric acylation transition state models are proposed to rationalize the origins of enantiodiscrimination in this process. This KR procedure was also translated to a continuous-flow process using a polymer-supported variant of the catalyst.

14.
Org Lett ; 22(1): 335-339, 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31868371

RESUMO

The use of silyl nitronates is reported for the isothiourea-catalyzed synthesis of γ-nitro-substituted silyl esters containing up to two contiguous stereocenters in good yields with excellent enantioselectivities (up to 93% yield and 99:1 er). The serendipitously discovered formation of silyl ester products in this reaction demonstrates a novel platform for catalyst turnover in α,ß-unsaturated acyl ammonium catalysis.

15.
Chem Sci ; 11(15): 3885-3892, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-34122857

RESUMO

An isothiourea-catalysed enantioselective synthesis of novel tetrahydroindolizine derivatives is reported through a one-pot tandem sequential process. The application of 2-(pyrrol-1-yl)acetic acid in combination with either a trifluoromethyl enone or an α-keto-ß,γ-unsaturated ester in an enantioselective Michael addition-lactonisation process, followed by in situ ring-opening and cyclisation, led to a range of 24 tetrahydroindolizine derivatives containing three stereocentres in up to >95 : 5 dr and >99 : 1 er.

16.
Am J Phys Med Rehabil ; 98(8): 729-734, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31318755

RESUMO

OBJECTIVE: Manual lifting can be burdensome for people who care for power wheelchair users. Although technologies used for dependent transfers are helpful, they have shortcomings of their own. This study compares the usability and task load demand of a novel robot-assisted transfer device to a clinical standard when performing dependent transfers. DESIGN: A cross-sectional study was conducted to assess caregivers (N = 21) transferring a 56-kg mannequin with the Strong Arm and Hoyer Advance at three transfer locations. Feedback was gathered through qualitative surveys. RESULTS: Usability was significant in multiple areas important for transfers. Caregiver fatigue and discomfort intensity were reduced, and the Strong Arm was preferred at the three transfer locations. Device ease and efficiency favored Strong Arm at two stations as was discomfort frequency. In addition, physical demand, frustration, and effort were significantly lower using Strong Arm compared with the Hoyer Advance. CONCLUSIONS: Compared with the Hoyer, participants favored Strong Arm for transfer usability and task load demand. However, further Strong Arm developments are needed.


Assuntos
Movimentação e Reposicionamento de Pacientes/instrumentação , Robótica , Tecnologia Assistiva , Cadeiras de Rodas , Adulto , Cuidadores , Estudos Transversais , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Suporte de Carga , Adulto Jovem
17.
Chem Sci ; 10(24): 6162-6173, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31360423

RESUMO

The enantioselective preparation of a range of perfluoroalkyl-substituted ß-lactones through an isothiourea (HyperBTM) catalysed reaction using symmetric anhydrides as ammonium enolate precursors and perfluoroalkylketones (RF = CF3, C2F5, C4F9) is reported. Following optimisation, high diastereo- and enantioselectivity was observed for ß-lactone formation using C2F5- and C4F9-substituted ketones at room temperature (26 examples, up to >95 : 5 dr and >99 : 1 er), whilst -78 °C was necessary for optimal dr and er with CF3-substituted ketones (11 examples, up to >95 : 5 dr and >99 : 1 er). Derivatisation of the ß-lactones through ring-opening, as well as a two-step conversion to give perfluoroalkyl-substituted oxetanes, is demonstrated without loss of stereochemical integrity. Density functional theory computations, alongside 13C natural abundance KIE studies, have been used to probe the reaction mechanism with a concerted asynchronous [2 + 2]-cycloaddition pathway favoured over a stepwise aldol-lactonisation process.

18.
J Am Chem Soc ; 141(25): 10099-10108, 2019 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-31150210

RESUMO

Iron-catalyzed hydromagnesiation of styrene derivatives offers a rapid and efficient method to generate benzylic Grignard reagents, which can be applied in a range of transformations to provide products of formal hydrofunctionalization. While iron-catalyzed methodologies exist for the hydromagnesiation of terminal alkenes, internal alkynes, and styrene derivatives, the underlying mechanisms of catalysis remain largely undefined. To address this issue and determine the divergent reactivity from established cross-coupling and hydrofunctionalization reactions, a detailed study of the bis(imino)pyridine iron-catalyzed hydromagnesiation of styrene derivatives is reported. Using a combination of kinetic analysis, deuterium labeling, and reactivity studies as well as in situ 57Fe Mössbauer spectroscopy, key mechanistic features and species were established. A formally iron(0) ate complex [ iPrBIPFe(Et)(CH2═CH2)]- was identified as the principle resting state of the catalyst. Dissociation of ethene forms the catalytically active species which can reversibly coordinate the styrene derivative and mediate a direct and reversible ß-hydride transfer, negating the necessity of a discrete iron hydride intermediate. Finally, displacement of the tridentate bis(imino)pyridine ligand over the course of the reaction results in the formation of a tris-styrene-coordinated iron(0) complex, which is also a competent catalyst for hydromagnesiation.


Assuntos
Complexos de Coordenação/química , Magnésio/química , Compostos Organometálicos/síntese química , Estirenos/química , Catálise , Ferro/química , Cinética , Ligantes , Piridinas/química
19.
Chemistry ; 25(11): 2816-2823, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30548466

RESUMO

An operationally simple isothiourea-catalysed acylative kinetic resolution of unprotected 1,1'-biaryl-2,2'-diol derivatives has been developed to allow access to axially chiral compounds in highly enantioenriched form (s values up to 190). Investigation of the reaction scope and limitations provided three key observations: i) the diol motif of the substrate was essential for good conversion and high s values; ii) the use of an α,α-disubstituted mixed anhydride (2,2-diphenylacetic pivalic anhydride) was critical to minimize diacylation and give high selectivity; iii) the presence of substituents in the 3,3'-positions of the diol hindered effective acylation. This final observation was exploited for the highly regioselective acylative kinetic resolution of unsymmetrical biaryl diol substrates bearing a single 3-substituent. Based on the key observations identified, acylation transition state models have been proposed to explain the atropselectivity of this kinetic resolution.

20.
Chemistry ; 25(4): 1064-1075, 2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30357947

RESUMO

During an investigation into the potential union of Lewis basic isothiourea organocatalysis and gold catalysis, the formation of gold-isothiourea complexes was observed. These novel gold complexes were formed in high yield and were found to be air- and moisture stable. A series of neutral and cationic chiral gold(I) and gold(III) complexes bearing enantiopure isothiourea ligands was therefore synthesized and fully characterized. The steric and electronic properties of the isothiourea ligands was assessed through calculation of their percent buried volume and the synthesis and analysis of novel iridium(I)-isothiourea carbonyl complexes. The novel gold(I)- and gold(III)-isothiourea complexes have been applied in preliminary catalytic and biological studies, and display promising preliminary levels of catalytic activity and potency towards cancerous cell lines and clinically relevant enzymes.

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