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1.
Biomacromolecules ; 2024 May 07.
Article in English | MEDLINE | ID: mdl-38712827

ABSTRACT

Interface engineering is essential for cellulosic fiber-reinforced polymer composites to achieve high strength and toughness. In this study, carboxymethyl cellulose (CMC) functionalized with hydrophobic quaternary ammonium ions (QAs) were utilized to modify the interface between holocellulose fibers (HF) and acrylic resin. The wet HF/CMC papers were prepared by vacuum filtration, akin to papermaking, followed by cationic ion exchange with different hydrophobic QAs. Subsequently, the modified papers were dried, impregnated with an acrylic resin monomer, and cured to produce transparent composite films. The effect of the hydrophobic QA moieties on the structure and optical and mechanical properties of the HF/CMC/acrylic resin composites were investigated. The composite film with cetyltrimethylammonium (CTA)-functionalized CMC showed high optical transmittance (87%) with low haze (43%), while the composite film with phenyltrimethylammonium (PTMA)-functionalized CMC demonstrated high Young's modulus of 7.6 GPa and high tensile strength of 180 MPa. These properties are higher than those of the composites prepared through covalent interfacial modification strategies. The results highlighted the crucial role of hydrophobic functionalized CMCs in facilitating homogeneous resin impregnation in the HF fiber network, producing a composite with enhanced interfacial adhesion strength, increased optical transparency, and mechanical strength. This facile use of hydrophobic CMCs as interfacial compatibilizers provides an energy-efficient route for preparing transparent, thin, and flexible composite films favorable in optoelectronic applications.

2.
Phys Ther Sport ; 65: 74-82, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38070289

ABSTRACT

OBJECTIVES: To measure lumbopelvic movement control in powerlifters with and without low back pain (LBP). DESIGN: Quantitative Cross-sectional. PARTICIPANTS: Twelve powerlifters with LBP and 28 powerlifters without LBP. SETTING: Powerlifters were recruited in nine different cities and filmed while performing a movement control test battery. MAIN OUTCOME MEASURES: Lumbopelvic movement control test battery consisting of seven tests, with a possible score between 0 and 13. The tests were rated by a physical therapist blinded to the group allocation and comparisons of the frequency of current/incorrect tests between groups were calculated. RESULTS: There was no statistically significant difference in the movement control test battery between the powerlifters with LBP (Median = 7.0, (2-11)) and powerlifters without LBP (Median = 6.0, (1-10)) (P = 0.59). There were no statistically significant differences between groups when the individual movement control tests were analyzed separately. CONCLUSIONS: The lack of significant differences between groups indicates that performance in lumbopelvic movement control test might not be associated with LBP in powerlifters. More studies on associations between LBP and movement control and other body functions are needed to guide assessment and treatment of powerlifters with LBP and for investigation of possible risk factors for LBP in powerlifters.


Subject(s)
Low Back Pain , Humans , Low Back Pain/therapy , Lumbosacral Region , Cross-Sectional Studies , Movement , Risk Factors
3.
ACS Nano ; 18(3): 1882-1891, 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38048271

ABSTRACT

The improvement of properties in nanocomposites obtained by topochemical surface modification, e.g., acetylation, of the nanoparticles is often ascribed to improved compatibility between the nanoparticle and the matrix. It is not always clear however what is intended: specific interactions at the interface leading to increased adhesion or the miscibility between the nanoparticle and the polymer. In this work, it is demonstrated that acetylation of cellulose nanocrystals greatly improves mechanical properties of their nanocomposites with polycaprolactone. In addition, molecular dynamics simulations with a combination of potential of mean force calculations and computational alchemy are employed to analyze the surface energies between the two components. The work of adhesion between the two phases decreases with acetylation. It is discussed how acetylation can still contribute to the miscibility, which leads to a stricter use of the concept of compatibility. The integrated experimental-modeling toolbox used has wide applicability for assessing changes in the miscibility of polymer nanocomposites.

4.
ACS Appl Mater Interfaces ; 15(50): 58850-58860, 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-38055951

ABSTRACT

Transparent wood composites (TWs) offer the possibility of unique coloration effects. A colored transparent wood composite (C-TW) with enhanced fire retardancy was impregnated by metal ion solutions, followed by methyl methacrylate (MMA) impregnation and polymerization. Bleached birch wood with a preserved hierarchical structure acted as a host for metal ions. Cobalt, nickel, copper, and iron metal salts were used. The location and distribution of metal ions in C-TW as well as the mechanical performance, optical properties, and fire retardancy were investigated. The C-TW coloration is tunable by controlling the metal ion species and concentration. The metal ions reduced heat release rates and limited the production of smoke during forced combustion tests. The potential for scaled-up production was verified by fabricating samples with a dimension of 180 × 100 × 1 (l × b × h) mm3.

6.
BMC Geriatr ; 23(1): 535, 2023 09 02.
Article in English | MEDLINE | ID: mdl-37660032

ABSTRACT

BACKGROUND: While assessment tools can increase the detection of cognitive impairment, there is currently insufficient evidence regarding clinical outcomes based on screening for cognitive impairment in older adults. METHODS: The study purpose was to investigate whether Timed Up and Go dual-task test (TUGdt) results, based on TUG combined with two different verbal tasks (name different animals, TUGdt-NA, and recite months in reverse order, TUGdt-MB), predicted dementia incidence over a period of five years among patients (N = 186, mean = 70.7 years; 45.7% female) diagnosed with Subjective Cognitive Impairment (SCI) and Mild Cognitive Impairment (MCI) following assessment at two memory clinics. Associations between TUG parameters and dementia incidence were examined in Cox regression models. RESULTS: During follow-up time (median (range) 3.7 (0.1-6.1) years) 98 participants converted to dementia. Novel findings indicated that the TUGdt parameter words/time, after adjustment for age, gender, and education, can be used for the prediction of conversion to dementia in participants with SCI or MCI over a period of five years. Among the TUG-related parameters investigated, words/time showed the best predictive capacity, while time scores of TUG and TUGdt as well as TUGdt cost did not produce significant predictive results. Results further showed that the step parameter step length during TUGdt predicts conversion to dementia before adjustment for age, gender, and education. Optimal TUGdt cutoffs for predicting dementia at 2- and 4-year follow-up based on words/time were calculated. The sensitivity of the TUGdt cutoffs was high at 2-year follow-up: TUGdt-NA words/time, 0.79; TUGdt-MB words/time, 0.71; reducing respectively to 0.64 and 0.65 at 4-year follow-up. CONCLUSIONS: TUGdt words/time parameters have potential as cost-efficient tools for conversion-to-dementia risk assessment, useful for research and clinical purposes. These parameters may be able to bridge the gap of insufficient evidence for such clinical outcomes. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05893524: https://www. CLINICALTRIALS: gov/study/NCT05893524?id=NCT05893524&rank=1 .


Subject(s)
Cognitive Dysfunction , Dementia , Memory, Episodic , Female , Humans , Animals , Male , Educational Status , Ambulatory Care Facilities , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/epidemiology , Dementia/diagnosis , Dementia/epidemiology
7.
Int J Sports Phys Ther ; 18(4): 820-830, 2023.
Article in English | MEDLINE | ID: mdl-37547841

ABSTRACT

Background: Maintaining neutral spinal alignment is considered important when performing the barbell back squat exercise. Since male and female lifters may differ in injury location it is important to examine whether they differ in spinal alignment during the back squat. Objectives: The study aimed to quantify the spinal alignment in the upper and lower lumbar spine during the barbell back squat exercise in male and female lifters. Secondary aims were to compare alignment during the back squat to standing habitual lumbar spine alignment and determine whether male and female lifters differ in these aspects. Study Design: Observational, Cross-sectional. Methods: Competitive power- and weightlifters were recruited and performed three repetitions of the barbell back squat exercise using a load equivalent to 70% of their one-repetition maximum. Spinal alignment and range of motion were measured using inertial measurement units placed on the thoracic, lumbar and sacral spine. Data was presented descriptively and comparisons between men and women as well as spinal alignment in four different positions were done with a factorial repeated measures analysis of variance. Results: Twenty-three (14 males, 9 females) were included. During execution of the squat, spinal alignment adjustments in the lumbar spine were made in all three planes of movement, compared to the start position, in both male and female lifters. Compared to their standing habitual posture, all lifters adjusted their upper lumbar spine to a less lordotic position when in the start position of the back squat (standing upright with the barbell on their back). Only male lifters assumed a less lordotic alignment in their lower lumbar spine in the start position compared their habitual posture. Conclusions: Adjustments of spinal alignment, predominantly in the sagittal plane, are made during execution of the back squat in both male and female lifters. Further, lifters adopt a less lordotic alignment with a heavy barbell on their upper back, more so in male than female lifters. In conclusion, it seems that spinal alignment changes noticeably during the barbell back squat. Level of Evidence: 3©The Author(s).

8.
ACS Nano ; 17(16): 15810-15820, 2023 Aug 22.
Article in English | MEDLINE | ID: mdl-37531258

ABSTRACT

Cellulose nanofibrils (CNF) with 2D silicate nanoplatelet reinforcement readily form multifunctional composites by vacuum-assisted self-assembly from hydrocolloidal mixtures. The final nanostructure is formed during drying. The crystalline nature of CNF and montmorillonite (MTM) made it possible to use synchrotron X-ray scattering (WAXS, SAXS) to monitor structural development during drying from water and from ethanol. Nanostructural changes in the CNF and MTM crystals were investigated. Changes in the out-of-plane orientation of CNF and MTM were determined. Residual drying strains previously predicted from theory were confirmed in both cellulose and MTM platelets due to capillary forces. The formation of tactoid platelet stacks could be followed. We propose that after filtration, the constituent nanoparticles in the swollen, solid gel already have a "fixed" location, although self-assembly and ordering processes take place during drying.

9.
J Am Heart Assoc ; 12(17): e029648, 2023 09 05.
Article in English | MEDLINE | ID: mdl-37584219

ABSTRACT

Background Pain increases the risk for cardiovascular diseases, including myocardial infarction (MI). However, the impact of pain on mortality after MI has not yet been investigated in large studies with long-term follow-up periods. Thus, we aimed to examine various levels of pain severity 1 year after an MI as a potential risk for all-cause mortality. Methods and Results We collected data from 18 376 patients, aged <75 years, who had a registered MI event during the period from 2004 to 2013 and with measurements of potential cardiovascular risk indicators at hospital discharge from the Swedish quality register SWEDEHEART (Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies). Self-reported levels of experienced pain according to EuroQol-5 dimension instrument were recorded in secondary prevention clinics 1 year after hospital discharge. We collected all-cause mortality data up to 8.5 years (median, 3.4 years) after the 1-year visit. The Cox proportional hazard regression was used to estimate hazard ratio (HR) and 95% CI. Moderate pain and extreme pain were reported by 38.2% and 4.5%, respectively, of included patients. There were 1067 deaths. Adjusted HR was 1.35 (95% CI, 1.18-1.55) and 2.06 (95% CI, 1.63-2.60) for moderate and extreme pain, respectively. Pain was a stronger mortality predictor than smoking. Conclusions Pain 1 year after MI is highly prevalent, and its effect on mortality 1 year after MI was found to be more pronounced than smoking. Clinicians managing patients after MI should recognize the need to consider experienced pain when making prognosis or treatment decisions.


Subject(s)
Myocardial Infarction , Humans , Self Report , Myocardial Infarction/complications , Smoking , Prognosis , Patient Discharge , Registries
10.
J Lipid Res ; 64(9): 100420, 2023 09.
Article in English | MEDLINE | ID: mdl-37482217

ABSTRACT

Reducing dietary saturated fatty acids (SFA) intake results in a clinically significant lowering of low-density lipoprotein cholesterol (LDL-C) across ethnicities. In contrast, dietary SFA's role in modulating emerging cardiovascular risk factors in different ethnicities remains poorly understood. Elevated levels of lipoprotein(a) [Lp(a)], an independent cardiovascular risk factor, disproportionally affect individuals of African descent. Here, we assessed the responses in Lp(a) levels to dietary SFA reduction in 166 African Americans enrolled in GET-READI (The Gene-Environment Trial on Response in African Americans to Dietary Intervention), a randomized controlled feeding trial. Participants were fed two diets in random order for 5 weeks each: 1) an average American diet (AAD) (37% total fat: 16% SFA), and 2) a diet similar to the Dietary Approaches to Stop Hypertension (DASH) diet (25% total fat: 6% SFA). The participants' mean age was 35 years, 70% were women, the mean BMI was 28 kg/m2, and the mean LDL-C was 116 mg/dl. Compared to the AAD diet, LDL-C was reduced by the DASH-type diet (mean change: -12 mg/dl) as were total cholesterol (-16 mg/dl), HDL-C (-5 mg/dl), apoA-1 (-9 mg/dl) and apoB-100 (-5 mg/dl) (all P < 0.0001). In contrast, Lp(a) levels increased following the DASH-type diet compared with AAD (median: 58 vs. 44 mg/dl, P < 0.0001). In conclusion, in a large cohort of African Americans, reductions in SFA intake significantly increased Lp(a) levels while reducing LDL-C. Future studies are warranted to elucidate the mechanism(s) underlying the SFA reduction-induced increase in Lp(a) levels and its role in cardiovascular risk across populations.


Subject(s)
Black or African American , Diet , Dietary Fats , Adult , Female , Humans , Male , Cholesterol, LDL/blood , Dietary Fats/administration & dosage , Lipoprotein(a)/blood
11.
Adv Mater ; 35(45): e2301163, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37491007

ABSTRACT

A multifunctional soft material with high ionic and electrical conductivity, combined with high mechanical properties and the ability to change shape can enable bioinspired responsive devices and systems. The incorporation of all these characteristics in a single material is very challenging, as the improvement of one property tends to reduce other properties. Here, a nanocomposite film based on charged, high-aspect-ratio 1D flexible nanocellulose fibrils, and 2D Ti3 C2 Tx MXene is presented. The self-assembly process results in a stratified structure with the nanoparticles aligned in-plane, providing high ionotronic conductivity and mechanical strength, as well as large water uptake. In hydrogel form with 20 wt% liquid, the electrical conductivity is over 200 S cm-1 and the in-plane tensile strength is close to 100 MPa. This multifunctional performance results from the uniquely layered composite structure at nano- and mesoscales. A new type of electrical soft actuator is assembled where voltage as low as ±1 V resulted in osmotic effects and giant reversible out-of-plane swelling, reaching 85% strain.

12.
J Expo Sci Environ Epidemiol ; 33(5): 699-709, 2023 09.
Article in English | MEDLINE | ID: mdl-37481638

ABSTRACT

BACKGROUND: Concerns have been raised whether exposure to endocrine-disrupting chemicals (EDCs) can alter reproductive functions and play a role in the aetiology of infertility in women. With increasing evidence of adverse effects, information on factors associated with exposure is necessary to form firm recommendations aiming at reducing exposure. OBJECTIVE: Our aim was to identify associations between lifestyle factors including the home environment, use of personal care products (PCP), and dietary habits and concentrations of EDCs in ovarian follicular fluid. METHODS: April-June 2016, 185 women undergoing ovum pick-up for in vitro fertilisation in Sweden were recruited. Correlation analyses were performed between self-reported lifestyle factors and concentration of EDCs analysed in follicular fluid. Habits related to cleaning, PCPs, and diet were assessed together with concentration of six per- and polyfluoroalkyl substances (PFASs) [PFHxS, PFOA, PFOS, PFNA, PFDA and PFUnDA], methyl paraben and eight phthalate metabolites [MECPP, MEHPP, MEOHP, MEHP, cxMinCH, cxMiNP, ohMiNP, MEP, MOHiBP]. Spearman's partial correlations were adjusted for age, parity and BMI. RESULTS: Significant associations were discovered between multiple lifestyle factors and concentrations of EDCs in ovarian follicular fluid. After correcting p values for multiple testing, frequent use of perfume was associated with MEP (correlation ρ = 0.41 (confidence interval 0.21-0.47), p < 0.001); hens' egg consumption was positively associated with PFOS (ρ = 0.30 (0.15-0.43), p = 0.007) and PFUnDA (ρ = 0.27 (0.12-0.40), p = 0.036). White fish consumption was positively associated with PFUnDA (ρ = 0.34 (0.20-0.47), p < 0.001) and PFDA (ρ = 0.27 (0.13-0.41), p = 0.028). More correlations were discovered when considering the raw uncorrected p values. Altogether, our results suggest that multiple lifestyle variables affect chemical contamination of follicular fluid. IMPACT STATEMENT: This study shows how lifestyle factors correlate with the level of contamination in the ovary by both persistent and semi-persistent chemicals in women of reproductive age. Subsequently, these data can be used to form recommendations regarding lifestyle to mitigate possible negative health outcomes and fertility problems associated with chemical exposure, and to inform chemical policy decision making. Our study can also help form the basis for the design of larger observational and intervention studies to examine possible effects of lifestyle changes on exposure levels, and to unravel the complex interactions between biological factors, lifestyle and chemical exposures in more detail.


Subject(s)
Environmental Pollutants , Fluorocarbons , Pregnancy , Humans , Female , Animals , Environmental Pollutants/adverse effects , Environmental Pollutants/analysis , Follicular Fluid/chemistry , Parabens/adverse effects , Parabens/analysis , Chickens , Fluorocarbons/adverse effects , Fluorocarbons/analysis , Life Style
13.
Ups J Med Sci ; 1282023.
Article in English | MEDLINE | ID: mdl-37265585

ABSTRACT

Background: Stress-related biomarkers have the potential to provide objective measures of whether interventions directed at people with dementia (PWD) and their family caregivers (FCG) are successful. The use of such biomarkers has been limited by logistical barriers to sample collection. Objective: Explore saliva concentration of steroid hormones in dementia care dyads during a music intervention. Methods: Consecutive PWD attending a memory evaluation center and their FCG were allocated to either an intervention-with-music or a non-intervention control group. All were living at home. Stress biomarkers, salivary cortisol and dehydroepiandrosterone sulfate (DHEA-S) samples were collected by the PWD and their FCG, in the morning and evening, 5 days a week, for 8 consecutive weeks. Biomarker concentrations of the intervention and the control groups were compared at week 8, in an intention-to-treat approach with adjustment for baseline value. Results: Twenty-four PWD in the intervention group and 10 in the control group, and their FCG were included in the analyses. The mean number of morning saliva collections was similar in the intervention and the control groups, ranging from 4.3 to 4.9 per participant weekly during the first 7 weeks, declining to 3.3 during week 8. Median log morning cortisol (pg/mL) among caregivers was lower in the intervention group than in the control group (8.09 vs. 8.57, P = 0.0133). Conclusion: This study demonstrates that music intervention was associated with lower morning saliva cortisol concentrations for FCGs.


Subject(s)
Dementia , Music Therapy , Music , Humans , Hydrocortisone/analysis , Saliva/chemistry , Caregivers , Biomarkers , Dementia/therapy
14.
Atherosclerosis ; 374: 107-120, 2023 06.
Article in English | MEDLINE | ID: mdl-37188555

ABSTRACT

In 2022, the European Atherosclerosis Society (EAS) published a new consensus statement on lipoprotein(a) [Lp(a)], summarizing current knowledge about its causal association with atherosclerotic cardiovascular disease (ASCVD) and aortic stenosis. One of the novelties of this statement is a new risk calculator showing how Lp(a) influences lifetime risk for ASCVD and that global risk may be underestimated substantially in individuals with high or very high Lp(a) concentration. The statement also provides practical advice on how knowledge about Lp(a) concentration can be used to modulate risk factor management, given that specific and highly effective mRNA-targeted Lp(a)-lowering therapies are still in clinical development. This advice counters the attitude: "Why should I measure Lp(a) if I can't lower it?". Subsequent to publication, questions have arisen relating to how the recommendations of this statement impact everyday clinical practice and ASCVD management. This review addresses 30 of the most frequently asked questions about Lp(a) epidemiology, its contribution to cardiovascular risk, Lp(a) measurement, risk factor management and existing therapeutic options.


Subject(s)
Aortic Valve Stenosis , Atherosclerosis , Cardiovascular Diseases , Humans , Lipoprotein(a) , Risk Factors , Risk Assessment , Aortic Valve Stenosis/complications , Atherosclerosis/diagnosis , Atherosclerosis/epidemiology , Atherosclerosis/prevention & control , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/prevention & control
15.
Nat Commun ; 14(1): 2827, 2023 May 17.
Article in English | MEDLINE | ID: mdl-37198187

ABSTRACT

Optically transparent wood has been fabricated by structure-retaining delignification of wood and subsequent infiltration of thermo- or photocurable polymer resins but still limited by the intrinsic low mesopore volume of the delignified wood. Here we report a facile approach to fabricate strong transparent wood composites using the wood xerogel which allows solvent-free infiltration of resin monomers into the wood cell wall under ambient conditions. The wood xerogel with high specific surface area (260 m2 g-1) and high mesopore volume (0.37 cm3 g-1) is prepared by evaporative drying of delignified wood comprising fibrillated cell walls at ambient pressure. The mesoporous wood xerogel is compressible in the transverse direction and provides precise control of the microstructure, wood volume fraction, and mechanical properties for the transparent wood composites without compromising the optical transmittance. Transparent wood composites of large size and high wood volume fraction (50%) are successfully prepared, demonstrating potential scalability of the method.

16.
ACS Appl Opt Mater ; 1(5): 1043-1051, 2023 May 26.
Article in English | MEDLINE | ID: mdl-37255504

ABSTRACT

Aggregation-induced quenching often restricts emissive performance of optically active solid materials with embedded fluorescent dyes. Delignified and nanoporous wood readily adsorbs organic dyes and is investigated as a host material for rhodamine 6G (R6G). High concentration of R6G (>35 mM) is achieved in delignified wood without any ground-state dye aggregation. To evaluate emissive performance, a solid-state random dye laser is prepared using the dye-doped wood substrates. The performance in terms of lasing threshold and efficiency was improved with increased dye content due to the ability of delignified wood to disperse R6G.

17.
Am J Clin Nutr ; 118(1): 23-26, 2023 07.
Article in English | MEDLINE | ID: mdl-37178716

ABSTRACT

In this perspective, we discuss new evidence relating to current dietary recommendations to reduce SFA intake to modulate an individual's global risk of CVD. Although it is well established that lowering dietary SFA intake has a beneficial effect on LDL cholesterol concentrations, findings increasingly indicate an opposite effect on lipoprotein(a) [Lp(a)] concentrations. In recent years, many studies have firmly established a role for an elevated Lp(a) concentration as a genetically regulated, causal, and prevalent risk factor for CVD. However, there is less awareness of the effect of dietary SFA intake on Lp(a) concentrations. This study discusses this issue and highlights the contrasting effect of reducing dietary SFA intake on LDL cholesterol and Lp(a), 2 highly atherogenic lipoproteins. This calls attention to the need for precision nutrition approaches that move beyond a "one-size-fits-all" approach. To illustrate the contrast, we describe the dynamic contributions of Lp(a) and LDL cholesterol concentrations to CVD risk during interventions with a low-SFA diet, with the hope that this will stimulate further studies and discussions regarding dietary management of CVD risk.


Subject(s)
Cardiovascular Diseases , Dietary Fats , Humans , Dietary Fats/pharmacology , Cholesterol, LDL , Lipoprotein(a) , Cardiovascular Diseases/prevention & control , Fatty Acids , Diet , Risk Reduction Behavior
18.
Carbohydr Polym ; 312: 120788, 2023 Jul 15.
Article in English | MEDLINE | ID: mdl-37059528

ABSTRACT

Nacre-mimicking nanocomposites based on colloidal cellulose nanofibrils (CNFs) and clay nanoparticles show excellent mechanical properties, yet processing typically involves preparation of two colloids followed by a mixing step, which is time- and energy-consuming. In this study, a facile preparation method using low energy kitchen blenders is reported in which CNF disintegration, clay exfoliation and mixing carried out in one step. Compared to composites made from the conventional method, the energy demand is reduced by about 97 %; the composites also show higher strength and work to fracture. Colloidal stability, CNF/clay nanostructure, and CNF/clay orientation are well characterized. The results suggest favorable effects from hemicellulose-rich, negatively charged pulp fibers and corresponding CNFs. CNF disintegration and colloidal stability are facilitated with substantial CNF/clay interfacial interaction. The results show a more sustainable and industrially relevant processing concept for strong CNF/clay nanocomposites.

19.
J Aging Phys Act ; 31(5): 823-832, 2023 10 01.
Article in English | MEDLINE | ID: mdl-37019438

ABSTRACT

The Timed Up-and-Go (TUG) test has been combined with different verbal/cognitive tasks (i.e., TUG dual task [TUGdt]) as a form of motor-cognitive testing. However, it is still unclear how different TUGdt conditions affect gait among older adults. Thirty community-dwelling older adults, with mean age of 73 years, participated in the study. Data were collected using marker-free video recordings. Gait parameters were extracted using a semiautomatic deep learning system. Comparisons of execution time and gait parameter outcomes were made under TUG and three types of TUGdt test conditions: TUGdt-naming animals, TUGdt-months backwards, and TUGdt-serial 7s. Statistical analyses were based on mean values of the gait parameters for each participant and TUG condition, including TUGdt gait cost, that is, the relative difference between TUGdt and TUG. All the investigated TUGdt conditions resulted in varying degrees of gait parameter changes. Under TUGdt conditions, participants took shorter and slower steps, with TUGdt-serial 7s causing the largest interference.


Subject(s)
Gait , Independent Living , Humans
20.
Proc Natl Acad Sci U S A ; 120(18): e2218380120, 2023 May 02.
Article in English | MEDLINE | ID: mdl-37094114

ABSTRACT

The nature of mass transport in plants has recently inspired the development of low-cost and sustainable wood-based electronics. Herein, we report a wood electrochemical transistor (WECT) where all three electrodes are fully made of conductive wood (CW). The CW is prepared using a two-step strategy of wood delignification followed by wood amalgamation with a mixed electron-ion conducting polymer, poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS). The modified wood has an electrical conductivity of up to 69 Sm-1 induced by the formation of PEDOT:PSS microstructures inside the wood 3D scaffold. CW is then used to fabricate the WECT, which is capable of modulating an electrical current in a porous and thick transistor channel (1 mm) with an on/off ratio of 50. The device shows a good response to gate voltage modulation and exhibits dynamic switching properties similar to those of an organic electrochemical transistor. This wood-based device and the proposed working principle demonstrate the possibility to incorporate active electronic functionality into the wood, suggesting different types of bio-based electronic devices.

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