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1.
J Exp Orthop ; 11(3): e12069, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38957227

RESUMO

Purpose: This study assessed rotational mismatch between components after total knee arthroplasty (TKA) in the supine and standing positions and aimed to investigate the effect of rotational mismatch in the standing position on postoperative patient-reported outcome measures (PROMs). Methods: Seventy-one patients (71 knees) who underwent TKA for medial knee osteoarthritis were used to investigate rotational mismatches between components. Rotational mismatches between components were examined on postoperative standing whole-leg and supine knee radiographs using a three-dimensional-to-two-dimensional model image registration technique, and the angles between the reference axes of the components were measured. Component alignment was evaluated using postoperative computed tomography images, and a questionnaire (2011 version of the Knee Society Score: [KSS 2011]) was mailed to investigate postoperative PROMs. Results: In the entire cohort, rotational mismatches in the supine and standing positions were similar (p = 0.9315). In 15% of patients, the mismatch was large (>5°) in the supine position but small (<5°) in the standing position (overestimated group). However, in 23% of patients, the mismatch was small (<5°) in the supine position and large (>5°) in the standing position (underestimated group). The underestimated group had severe preoperative varus deformity, resulting in external rotation of both femoral and tibial components. Rotational mismatch in the standing position (p = 0.0032) was a significant risk factor for unfavourable PROMs. Patients with a mismatch in the standing position had significantly lower scores than those without a mismatch (p = 0.0215), exceeding the minimal clinically important difference values. Conclusions: The underestimated group is clinically important because the surgical procedure and intraoperative assessment of component placement are performed in the supine position. In cases of severe preoperative varus deformity, care should be taken not to place the component in malrotation to avoid rotational mismatch in the standing position. Level of Evidence: Ⅳ, Case series.

2.
Front Hum Neurosci ; 18: 1384305, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988825

RESUMO

Introduction: Attentional focus is a phenomenon in which shifting the focus of attention alters performance of standing postural control. It can be categorized as internal focus (IF), which directs attention to the body parts, or external focus (EF), which directs attention to the external environment. Although attentional focus that improves standing postural control in younger people exhibits individual dominance, the dominance of attentional focus in standing postural control in older adults remains ambiguous. Therefore, this study aimed to compare the dominance of attentional focus in standing postural control between healthy younger and older adults, a crucial step for understanding the aging process. Methods: The participants performed a standing postural control task under the IF and EF conditions. Based on the condition during which they exhibited superior performance, the participants were divided into two groups: IF-dominant and EF-dominant. The standing postural control performance in each group under the IF and EF conditions was subsequently compared. Results: The results showed that the participants, encompassing both younger and older adults, were divided into the IF-dominant and EF-dominant groups, confirming the dominance of attentional focus. The performance under the EF condition in older adults was also influenced by the dominance of attentional focus. Conclusion: These results highlight the potential importance of intervention methods based on the dominance of attentional focus, providing valuable insights into future research and clinical practice.

3.
Front Bioeng Biotechnol ; 12: 1375627, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38974656

RESUMO

Introduction: Degenerative lumbar disease (DLD) is a prevalent disorder that predominantly affects the elderly population, especially female. Extensive research has demonstrated that overweight individuals (categorized by body fat distribution) have a higher susceptibility to developing DLD and an increased risk of falling. However, there is limited research available on the standing balance and functional performance of overweight females with DLD. Aims: To determine the impact of body fat distribution on standing balance and functional performance in overweight females with DLD. Methods: This cross-sectional study evaluated thirty females with DLD were categorized into three types of body fat distribution based on body mass index (BMI) and waist-hip ratio, specifically as android-type, gynoid-type, and normal weight groups. In addition, a control group of ten age-matched females with normal weight was recruited. The Visual Analogue Scale, Roland Morris Disability Questionnaire, Cobb angle (Determined using x-ray), and body composition (Determined using the InBody S10), were conducted only on the DLD groups. All participants were assessed standing balance in the anteroposterior and mediolateral directions. The functional assessments included timed-up-and-go and 5-times-sit-to-stand tests. Results: There were 10 people in each group. Android-type (Age = 65.00 ± 6.34 years; BMI = 26.87 ± 2.05 kg/m2), Gynoid-type (Age = 65.60 ± 4.99 years; BMI = 26.60 ± 1.75 kg/m2), Normal weight (Age = 65.70 ± 5.92 years; BMI = 22.35 ± 1.26 kg/m2), and Control (Age = 65.00 ± 5.23 years; BMI = 22.60 ± 1.12 kg/m2). The android-type group had higher body fat, visceral fat, and lower muscle mass (p < 0.05), along with an increased Cobb angle (p < 0.05). They showed greater ellipse area, total excursion, and mean distance in the anteroposterior direction (p < 0.05). During the functional performance assessments, the android-type group had longer durations in both the 5-times-sit-to-stand and timed-up-and-go tasks (p < 0.05). Conclusion: Our study found that android-type overweight individuals showed postural instability, reduced functional performance, and insufficient lower limb muscle strength and mass. These findings might help physical therapists in planning interventions, as they imply that patients with DLD may require specific types of standing balance training and lower extremities muscle-strengthening based on their body fat distribution. Clinical Trial Registration: ClinicalTrials.gov, identifier NCT05375201.

4.
Small ; : e2403915, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38973115

RESUMO

In 2D materials, a key engineering challenge is the mass production of large-area thin films without sacrificing their uniform 2D nature and unique properties. Here, it is demonstrated that a simple fluid phenomenon of water/alcohol solvents can become a sophisticated tool for self-assembly and designing organized structures of 2D nanosheets on a water surface. In situ, surface characterizations show that water/alcohol droplets of 2D nanosheets with cationic surfactants exhibit spontaneous spreading of large uniform monolayers within 10 s. Facile transfer of the monolayers onto solid or flexible substrates results in high-quality mono- and multilayer films with high coverages (>95%) and homogeneous electronic/optical properties. This spontaneous spreading is quite general and can be applied to various 2D nanosheets, including metal oxides, graphene oxide, h-BN, MoS2, and transition metal carbides, enabling on-demand smart manufacture of large-size (>4 inchϕ) 2D nanofilms and free-standing membranes.

5.
Physiother Theory Pract ; : 1-8, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007907

RESUMO

BACKGROUND: Overall spinal curvature is evaluated by calculating the difference between the angles of lumbar lordosis (LL) and thoracic kyphosis (TK) and is expressed as LL minus TK (LL-TK). It is unclear whether LL-TK is associated with physical function in community-dwelling older adults and whether it is more relevant than TK or LL alone. OBJECTIVE: This study aimed to identify whether LL-TK is associated with physical function in community-dwelling older adults, and whether it is strongly associated than TK or LL alone. METHODS: The participants comprised 1,674 community-dwelling older adults who underwent physical assessments (women, n = 1,099; mean age, 67.4 ± 5.3 years). As spinal alignment indices, TK and LL were measured using skin surface methods, and LL-TK was calculated as the difference between them. Decreased LL-TK indicated increased overall spinal curvature. Physical function was determined by measuring single-leg standing, five-times chair-stand, and usual gait speed. Stepwise multiple regression analyses were performed with each physical function as the dependent variable and spinal alignment indices as the independent variables, with adjustments. RESULTS: Multiple regression analyses showed that single-leg standing (ß = 0.092, 95% confidence interval [CI] = 0.071 to 0.214, p < .001) and five-times chair-stand (ß=-0.142, 95% CI = -0.037 to -0.019, p < .001) were significantly associated with LL-TK, but not LL. Both LL-TK (ß = 0.121, 95% CI = 0.001 to 0.004, p < .001) and LL (ß = 0.087, 95% CI = 0.001 to 0.003, p = .003) were significant determinants of usual gait speed. CONCLUSIONS: This study showed that decreased LL-TK may be associated with poor physical function. This association may be stronger than that observed for TK or LL alone.

6.
Nanomaterials (Basel) ; 14(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38998699

RESUMO

The efficient dispersion of single-walled carbon nanotubes (SWCNTs) has been the subject of extensive research over the past decade. Despite these efforts, achieving individually dispersed SWCNTs at high concentrations remains challenging. In this study, we address the limitations associated with conventional methods, such as defect formation, excessive surfactant use, and the use of corrosive solvents. Our novel dispersion method utilizes the spontaneous charging of SWCNTs in a solvated electron system created by dissolving potassium in hexamethyl phosphoramide (HMPA). The resulting charged SWCNTs (c-SWCNTs) can be directly dispersed in the charging medium using only magnetic stirring, leading to defect-free c-SWCNT dispersions with high concentrations of up to 20 mg/mL. The successful dispersion of individual c-SWCNT strands is confirmed by their liquid-crystalline behavior. Importantly, the dispersion medium for c-SWCNTs exhibits no reactivity with metals, polymers, or other organic solvents. This versatility enables a wide range of applications, including electrically conductive free-standing films produced via conventional blade coating, wet-spun fibers, membrane electrodes, thermal composites, and core-shell hybrid microparticles.

7.
Sensors (Basel) ; 24(13)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-39000818

RESUMO

BACKGROUND: the feasibility of the capacitance method for detecting the water content in standing tree trunks was investigated using capacitance-based equipment that was designed for measuring the water content of standing tree trunks. METHODS: In laboratory experiments, the best insertion depth of the probe for standing wood was determined by measurement experiments conducted at various depths. The bark was to be peeled when specimens and standing wood were being measured. The actual water content of the test object was obtained by specimens being weighed and the standing wood being weighed after the wood core was extracted. RESULTS: A forecast of the moisture content of standing wood within a range of 0 to 180% was achieved by the measuring instrument. The feasibility of the device for basswood and fir trees is preliminarily studied. When compared to the drying method, the average error of the test results was found to be less than 8%, with basswood at 7.75%, and fir at 7.35%. CONCLUSIONS: It was concluded that the measuring instrument has a wide measuring range and is suitable for measuring wood with low moisture content, as well as standing timber with high moisture content. The measuring instrument, being small in size, easy to carry, and capable of switching modes, is considered to have a good application prospect in the field of forest precision monitoring and quality improvement.


Assuntos
Capacitância Elétrica , Árvores , Água , Madeira , Água/química , Madeira/química
8.
Clin Biomech (Bristol, Avon) ; 117: 106297, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38954887

RESUMO

BACKGROUND: Long-leg frontal radiographs of the lower extremities are used to assess knee osteoarthritis. Given the three-dimensional (3D) nature of alignment changes in osteoarthritis, postural alterations in the femur and tibia extend beyond the coronal plane (in-plane) to include the transverse and sagittal planes (out-of-plane). This study investigates the impact of these out-of-plane factors on in-plane knee alignment parameters observed in frontal radiographs. METHODS: A total of 97 osteoarthritic knees in women were examined. Using a 3D-to-two-dimensional (2D) image matching technique, we evaluated the 3D postures of the femur and tibia in the standing position as viewed from frontal radiographs in the world coordinate system. Statistical analyses were conducted to explore associations between these 3D postures and 2D alignment parameters obtained from frontal radiographs under identical conditions. FINDINGS: The femur exhibited a medial inclination of 2.7°, a posterior inclination of 3.9°, and an internal rotation of 4.2°, whereas the tibia showed a lateral inclination of 6.4°, an anterior inclination of 6.7°, and an internal rotation of 6.7°. Both coronal and rotational postures of femur and tibia influenced the hip-knee-ankle angle, mechanical axis percentage, and medial proximal tibial angle. However, only coronal factors of tibia impacted tibial joint line obliquity relative to the floor. INTERPRETATION: Attention should be paid to the potential impact of the out-of-plane postures of the femur and tibia on parameters assessed in plain frontal radiographs of the lower extremities.


Assuntos
Fêmur , Imageamento Tridimensional , Osteoartrite do Joelho , Postura , Radiografia , Tíbia , Humanos , Feminino , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/fisiopatologia , Tíbia/diagnóstico por imagem , Tíbia/fisiopatologia , Fêmur/diagnóstico por imagem , Fêmur/fisiopatologia , Idoso , Imageamento Tridimensional/métodos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/fisiopatologia , Posição Ortostática , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade
9.
Intern Emerg Med ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39001977

RESUMO

Acute vertigo is defined as the perception of movement of oneself or the surroundings in the absence of actual motion and it is a frequent cause for emergency department admissions. The utilization of medical resources and the duration of hospital stay for this kind of symptom is high. Furthermore, the efficiency of brain imaging in the acute phase is low, considering the limited sensitivity of both CT and MRI for diagnosing diseases that are the causes of central type of vertigo. Relying on imaging tests can provide false reassurance in the event of negative results or prolong the in-hospital work-up improperly. On the other hand, clinical examinations, notably the assessment of nystagmus' features, have proven to be highly accurate and efficient when performed by experts. Literature data point out that emergency physicians often do not employ these skills or use them incorrectly. Several clinical algorithms have been introduced in recent years with the aim of enhancing the diagnostic accuracy of emergency physicians when evaluating this specific pathology. Both the 'HINTS and 'STANDING' algorithms have undergone external validation in emergency physician hands, showing good diagnostic accuracy. The objective of this consensus document is to provide scientific evidence supporting the clinical decisions made by physicians assessing adult patients with acute vertigo in the emergency department, particularly in cases without clear associated neurological signs. The document aims to offer a straightforward and multidisciplinary approach. At the same time, it tries to delineate benchmarks for the formulation of local diagnostic and therapeutic pathways, as well as provide a base for the development of training and research initiatives.

10.
Glob Chang Biol ; 30(6): e17347, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38822663

RESUMO

Climate change (CC) necessitates reforestation/afforestation programs to mitigate its impacts and maximize carbon sequestration. But comprehending how tree growth, a proxy for fitness and resilience, responds to CC is critical to maximize these programs' effectiveness. Variability in tree response to CC across populations can notably be influenced by the standing genetic variation encompassing both neutral and adaptive genetic diversity. Here, a framework is proposed to assess tree growth potential at the population scale while accounting for standing genetic variation. We applied this framework to black spruce (BS, Picea mariana [Mill] B.S.P.), with the objectives to (1) determine the key climate variables having impacted BS growth response from 1974 to 2019, (2) examine the relative roles of local adaptation and the phylogeographic structure in this response, and (3) project BS growth under two Shared Socioeconomic Pathways while taking standing genetic variation into account. We modeled growth using a machine learning algorithm trained with dendroecological and genetic data obtained from over 2600 trees (62 populations divided in three genetic clusters) in four 48-year-old common gardens, and simulated growth until year 2100 at the common garden locations. Our study revealed that high summer and autumn temperatures negatively impacted BS growth. As a consequence of warming, this species is projected to experience a decline in growth by the end of the century, suggesting maladaptation to anticipated CC and a potential threat to its carbon sequestration capacity. This being said, we observed a clear difference in response to CC within and among genetic clusters, with the western cluster being more impacted than the central and eastern clusters. Our results show that intraspecific genetic variation, notably associated with the phylogeographic structure, must be considered when estimating the response of widespread species to CC.


Assuntos
Sequestro de Carbono , Mudança Climática , Variação Genética , Picea , Árvores , Picea/genética , Picea/crescimento & desenvolvimento , Árvores/genética , Árvores/crescimento & desenvolvimento , Filogeografia
11.
Small ; : e2402511, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38837861

RESUMO

Electrocatalytic water splitting (EWS) driven by renewable energy is widely considered an environmentally friendly and sustainable approach for generating hydrogen (H2), an ideal energy carrier for the future. However, the efficiency and economic viability of large-scale water electrolysis depend on electrocatalysts that can efficiently accelerate the electrochemical reactions taking place at the two electrodes. Wood-derived nanomaterials are well-suited for serving as EWS catalysts because of their hierarchically porous structure with high surface area and low tortuosity, compositional tunability, cost-effectiveness, and self-standing integral electrode configuration. Here, recent advancements in the design and synthesis of wood-structured nanomaterials serving as advanced electrocatalysts for water splitting are summarized. First, the design principles and corresponding strategies toward highly effective wood-structured electrocatalysts (WSECs) are emphasized. Then, a comprehensive overview of current findings on WSECs, encompassing diverse structural designs and functionalities such as supported-metal nanoparticles (NPs), single-atom catalysts (SACs), metal compounds, and heterostructured electrocatalysts based on engineered wood hosts are presented. Subsequently, the application of these WSECs in various aspects of water splitting, including the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), overall water splitting (OWS), and hybrid water electrolysis (HWE) are explored. Finally, the prospects, challenges, and opportunities associated with the broad application of WSECs are briefly discussed. This review aims to provide a comprehensive understanding of the ongoing developments in water-splitting catalysts, along with outlining design principles for the future development of WSECs.

12.
Small ; : e2400812, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38845480

RESUMO

Manufacturing high-performance and cost-affordable non-metallic, electroactive 1D carbon material for energy storage and hydrogen evolution reaction (HER) is of foremost importance to respond positively to the impending energy crisis. Porous N-doped carbon nanofiber (PNCNF) is successfully synthesized by electrospinning, using selenium nanoparticles as a sacrificial template (where Se is reutilized for ZIF-67 selenization as a bi-process, and the surface of PNCNF is modified with poly(3,4-ethylenedioxythiophene) (PNCNT/PEDOT) by electropolymerization. The prepared materials are found ideal for energy storage (supercapacitor) and electrocatalysis (HER). The bi-functional material has shown excellent energy storage capability with the specific capacitance (CS) of 230 F g-1 (PNCNF) and 395 F g-1 (PNCNF/PEDOT), and the symmetric supercapacitor device, PNCNF/PEDOT//PEDOT/PNCNF, exhibits 32.4 Wh kg-1 energy density at 14400 W kg-1 power density with 96.6% Coulombic efficiency and 106% CS at the end of 5000 charge-discharge cycles. The rate capability of the symmetric supercapacitor cell of PNCNF/PEDOT is 51% for the current density increase from 1 to 8 A g-1, while that of PNCNF is a meager 29% only. Electrocatalytic HER at the PNCNF electrode is achieved with an overpotential of 281 mV@10 mA cm-2 relative to the Pt/C electrode and a low Tafel slop value of 96 mV dec-1.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38928915

RESUMO

Children functioning at Gross Motor Function Classification System (GMFCS) levels IV-V cannot maintain an aligned standing position or take steps without support. Upright positioning and mobility devices have psycho-social significance for these children and their families, enhancing use of vision, communication, functioning and emotional well-being. Standers and supported stepping devices facilitate opportunities for biomechanical loading, potentially helping to build and maintain muscle and bone integrity, and they promote physical development. However, families are often required to choose between these two devices for their young child. This study aims to synthesize evidence for use and benefits of both supported standing and stepping devices through the lens of two contemporary theoretical frameworks to support clinical reasoning and implementation. The F-words for childhood development (functioning, family, fitness, fun, friends, future) and the interdependence-Human Activity Assistive Technology (iHAAT) models were combined to illustrate the complex interactions between the child, family, caregivers, peers and contextual factors when implementing standing and stepping devices with children at GMFCS levels IV and V. Supported standing and stepping devices provide complementary benefits, and both may be necessary starting at 9-15 months. We propose they both be included ON-Time, along with other age-appropriate positioning and mobility devices, to promote more equitable developmental opportunities for children with non-ambulant cerebral palsy.


Assuntos
Paralisia Cerebral , Criança , Pré-Escolar , Humanos , Tecnologia Assistiva , Posição Ortostática
14.
Micromachines (Basel) ; 15(6)2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38930756

RESUMO

Certain ocular conditions result from the non-physiological presence of intraocular particles, leading to visual impairment and potential long-term damage. This happens when the normally clear aqueous humor becomes less transparent, thus blocking the visual axis and by intraocular pressure elevation due to blockage of the trabecular meshwork, as seen in secondary open-angle glaucoma (SOAG). Some of these "particle-related pathologies" acquire ocular conditions like pigment dispersion syndrome, pseodoexfoliation and uveitis. Others are trauma-related, such as blood cell accumulation in hyphema. While medical and surgical treatments exist for SOAG, there is a notable absence of effective preventive measures. Consequently, the prevailing clinical approach predominantly adopts a "wait and see" strategy, wherein the focus lies on managing secondary complications and offers no treatment options for particulate matter disposal. We developed a new technique utilizing standing acoustic waves to trap and direct intraocular particles. By employing acoustic trapping at nodal regions and controlled movement of the acoustic transducer, we successfully directed these particles to specific locations within the angle. Here, we demonstrate control and movement of polystyrene (PS) particles to specific locations within an in vitro eye model, as well as blood cells in porcine eyes (ex vivo). The removal of particles from certain areas can facilitate the outflow of aqueous humor (AH) and help maintain optimal intraocular pressure (IOP) levels, resulting in a non-invasive tool for preventing secondary glaucoma. Furthermore, by controlling the location of trapped particles we can hasten the clearance of the AH and improve visual acuity and quality more effectively. This study represents a significant step towards the practical application of our technique in clinical use.

15.
J Orthop Surg (Hong Kong) ; 32(2): 10225536241258336, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38910029

RESUMO

Background: To observe the activation strategies of the ankle muscles using surface electromyography (sEMG) during single-leg standing (SLS) and both-leg standing (BLS) on flat ground (FG), soft mat (SM), and BOSU ball (BB) surfaces. Methods: Thirty healthy young adults participated in the study. The muscle activities of the tibialis anterior (TA) and gastrocnemius medial (GM) were measured on the three surfaces during SLS and BLS. Electromyographic evaluations of the TA and GM were recorded during maximum voluntary isometric contractions (MVIC). Muscle activation was evaluated using MVIC%, and muscle co-contraction was evaluated using the co-contraction index (CI). Results: A statistically significant increase was observed in the MVIC% of the TA, GM, and CI on the three surfaces during SLS compared to BLS, except for the comparison of CI on BB between SLS and BLS (t = -1.35, p = 0.19). The MVIC% of the TA and GM during SLS and BLS on BB was significantly increased in comparison with FG and SM. The CI during BLS on BB increased compared to FG (t = 3.19, p < 0.01) and SM (t = 4.64, p < 0.01). The CI during BLS on SM (t = -1.46, p = 0.15) decreased when compared to FG but without statistical significance. Conclusions: SLS and unstable surfaces can induce greater muscle activation, and SLS can have a greater influence on ankle muscles.


Assuntos
Eletromiografia , Músculo Esquelético , Posição Ortostática , Humanos , Masculino , Músculo Esquelético/fisiologia , Adulto Jovem , Feminino , Adulto , Articulação do Tornozelo/fisiologia , Contração Isométrica/fisiologia , Tornozelo/fisiologia , Equilíbrio Postural/fisiologia
16.
Ultrasonics ; 142: 107385, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38936288

RESUMO

The second harmonic generation (SHG) technique offers a quantitative damage parameter known as the acoustic nonlinearity parameter (ß) capable of detecting the change in the inherent material nonlinearity. However, current SHG methods, in particular, those used for measuring ß in construction materials, have an unresolved issue in their application due to limited sample sizes. The restricted sample dimensions lead to the generation of boundary-reflected waves, which hinder the selective detection of propagating waves and thus the precise evaluation of material nonlinearity through ß. Furthermore, the use of large samples limits the compatibility of the SHG method with other characterization modalities, such as mechanical tests, X-ray diffraction, and computerized tomography. To address this issue, this paper introduces a new SHG method that is based on the use of nonlinear standing waves - the dominant longitudinal standing waves in a forced-free configuration. The corrections for phase delay and attenuation effect of each reflected wave are made, enabling accurate measurements of ß in thin samples with no requirement in the thickness-wavelength ratio. The measured ß is then employed to quantify the microstructural modification in cement paste induced by thermal damage, validating the proposed method as a promising tool for quantifying microstructural changes in materials.

17.
Membranes (Basel) ; 14(6)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38921499

RESUMO

Aging in polymers of intrinsic microporosity has slowed exploitation due to a decay in performance over time since densification makes them unsuitable for industrial applications. This work aimed to study the impact of the operation and storage temperature on the gas separation properties and aging rates of PIM-1 self-standing films. The permeability, diffusivity, and solubility of the tested membranes were monitored through permeation tests for pure carbon dioxide and nitrogen at a maximum upstream pressure of 1.3 bar for temperatures ranging from -20 °C to 25 °C. This study found significant benefits in the operation of glassy polymeric membranes at low temperatures, resulting in a favourable trade-off in separation performance and a reduction in the aging rate by three orders of magnitude. This brings new opportunities for the industrial application of PIMs in innovative carbon capture processes.

18.
Wien Med Wochenschr ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38836949

RESUMO

BACKGROUND: Spinal cord injuries (SCIs) are a global concern, annually affecting hundreds of thousands of individuals. Among these cases, incomplete SCIs, allowing some muscle activity below the injury, pose unique challenges. This case study focuses on a 55-year-old male with a moderate incomplete SCI (AIS-D). CASE PRESENTATION: After initial treatments and pharmaceutical antispastic therapy, a novel intervention was introduced featuring the Standing Ovation gait exercise system (Standing Ovation GmbH, Hallwang, Austria). This individually tailored system, equipped with a rail system and seat-lifting unit, provided a secure environment for balance training. Over 14 training sessions spanning from October 13, 2021, to March 23, 2022, improvements in functional walking were observed. DISCUSSION AND CONCLUSION: Locomotor improvement in SCI rehabilitation is important; the potential of task-specific gait exercises with the Standing Ovation system in incomplete spinal cord injury seems to be a promising approach. Although promising, these findings call for further systematic studies with larger patient cohorts to strengthen their reliability. Ongoing research endeavors are essential to fully understand the benefits and limitations of this intervention in spinal cord injury rehabilitation.

19.
Cureus ; 16(5): e59973, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38854239

RESUMO

Long-standing overt ventriculomegaly in adults (LOVA) is a kind of chronic hydrocephalus that has been reported to have started in infancy and is characterized by severe ventriculomegaly and macrocephaly. It often manifests clinically in later adulthood. We describe the case of a 34-year-old male patient who had a history of chronic alcoholism and who had been complaining of headaches, disturbed gait, and frequent falls for three months when he arrived in a stupor at the emergency room. Massive ventriculomegaly with Evans' index of 0.40 was found during a head magnetic resonance imaging (MRI). The MRI results were more severe than the clinical manifestations. He was diagnosed with LOVA and treated with conservative hyperosmolar drugs, neuroprotective agents, and intravenous (IV) thiamine. The patient was discharged and consented to follow-up after a hospital stay of seven days.

20.
Equine Vet J ; 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38923039

RESUMO

BACKGROUND: Reported complication rates after dental repulsion for equine exodontia are high (up to 80%), but repulsion methods have changed notably in the last 20 years. OBJECTIVES: Describe the outcome for 20 cases after dental repulsion using small diameter repulsion pins. STUDY DESIGN: Retrospective case series. METHODS: Records of horses that underwent cheek tooth repulsion were reviewed (2014-2023). Inclusion criteria included: mandibular or maxillary cheek tooth extraction where oral extraction failed and repulsion was used to complete extraction, and where clinical follow up information was available. Repulsions were carried out under sedation with a regional nerve block or under a short general anaesthetic, using a small diameter repulsion pin (3-5 mm). Intra-operative radiographs facilitated instrument placement. The alveolus was packed with polymethyl methacrylate post-extraction. Horses were re-examined at 4-6 weeks post-operatively. RESULTS: Twenty cases were included. Patients had a mean age of 10.3 years old (range 5-16 years). The majority (75%) of teeth had pre-existing dental fractures. Maxillary (n = 15) and mandibular cheek teeth (n = 5) were all successfully repulsed, with 16 cases performed with the horse standing and 4 with the horse under general anaesthesia. Intra-operative complications included damage to the mandibular bone (n = 1). Short-term complications (n = 2) included superficial surgical site infection, and dehiscence of one sinus flap. Long-term complications included the recurrence of sinusitis (n = 1) and small intra-alveolar fragments causing persistent bitting problems in another patient. MAIN LIMITATIONS: Retrospective study design, small number of cases. CONCLUSIONS: When oral extraction fails, cheek tooth repulsion using small diameter repulsion pins is an effective extraction technique. The total intra- and post-operative complication rate was 25%, which is comparable to previously published complication rates for repulsion using Steinmann pins and also those encountered after trans-buccal screw extraction.

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