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Frontiers in Physiology 2024The purpose of this study was to compare acute responses between manual and automated blood flow restriction (BFR) systems.
UNLABELLED
The purpose of this study was to compare acute responses between manual and automated blood flow restriction (BFR) systems.
METHODS
A total of 33 individuals completed this study. On visit 1, arterial occlusion pressure (AOP, mm Hg), cardiovascular responses, and discomfort (RPE-D) were measured with each BFR system at rest. On visit 2, unilateral bicep curls were completed [30% one-repetition maximum; 50% AOP] with one system per arm. Muscle thickness (MT, cm) and maximal force (N) were assessed before (pre), immediately (post-0), 5 min (post-5), and 10 min (post-10) post-exercise. Ratings of perceived exertion (RPE-E) and ratings of perceived discomfort (RPE-D) were assessed throughout the exercise. AOP and repetitions were compared with Bayesian paired t-tests. Other outcomes were compared with Bayesian RMANOVAs. BF represents the likelihood of the best model vs. the null. The results are presented as mean ± SD.
RESULTS
Supine cardiovascular responses and RPE-D were similar for manual and automated (all BF ≤ 0.2). Supine AOP for manual (157 ± 20) was higher than that of automated (142 ± 17; BF = 44496.0), but similar while standing (manual: 141 ± 17; automated: 141 ± 22; BF = 0.2). MT (time, BF = 6.047e + 40) increased from Pre (3.9 ± 0.7) to Post-0 (4.4 ± 0.8; BF = 2.969e + 28), with Post-0 higher than Post-5 (4.3 ± 0.8) and Post-10 (4.3 ± 0.8; both BF ≥ 275.2). Force (time, BF = 1.246e + 29) decreased from Pre (234.5 ± 79.2) to Post-0 (149.8 ± 52.3; BF = 2.720e + 22) and increased from Post-0 to Post-5 (193.3 ± 72.7; BF = 1.744e + 13), with Post-5 to Post-10 (194.0 ± 70.6; BF = 0.2) being similar. RPE-E increased over sets. RPE-D was lower for manual than automated. Repetitions per set were higher for manual (Set 1: 37 ± 18; Set 4: 9 ± 5) than automated (Set 1: 30 ± 7; Set 4: 7 ± 3; all BF ≥ 9.7).
CONCLUSION
Under the same relative pressure, responses are mostly similar between BFR systems, although a manual system led to lower exercise discomfort and more repetitions.
PubMed: 38948082
DOI: 10.3389/fphys.2024.1409702 -
Journal of Indian Prosthodontic Society Jul 2024The aim is to determine thermal conduction by heat-activated polymethylmethacrylate (PMMA) infiltrated with 1 weight% Titanium Dioxide (TiO2) and 1 weight% Zirconium...
Effect of titanium dioxide and zirconium dioxide nanoparticle incorporation on the thermal conductivity of heat-activated polymethylmethacrylate denture base resins: An in vitro experimental study.
AIM
The aim is to determine thermal conduction by heat-activated polymethylmethacrylate (PMMA) infiltrated with 1 weight% Titanium Dioxide (TiO2) and 1 weight% Zirconium Dioxide (ZrO2) nanoparticles and to compare with that of conventional PMMA.
STUDY SETTING AND DESIGN
In vitro experimental study.
MATERIALS AND METHODS
Eighteen disc shaped specimens with a thickness of 5 mm and diameter of 50 mm, were fabricated and grouped according to the material used: Group B1 (resin infiltrated with 1 weight% TiO2), Group B2 (resin infiltrated with 1 weight% ZrO2), and Control Group B3 (heat-activated conventional PMMA resin). Disc-shaped specimens were analyzed for thermal conductivity using "modified guarded hot plate apparatus" in the thermal lab of the Indian Space Research Organisation.
STATISTICAL ANALYSIS USED
One-way ANOVA followed by Tukey's post hoc test was used to compare the arithmetic means of all three groups.
RESULTS
A statistically significant difference was noted among all three groups. Group B2 had the maximum thermal conductivity, followed by Group B1. Thermal conductivity was the least for Group B3. A post hoc comparison revealed that the difference was significant between Group B2 and Group B3.
CONCLUSION
Nano ZrO2 addition in PMMA increased its thermal conductivity. There is evidence that it improves its mechanical properties as well. Hence, Nano ZrO2 addition in PMMA is highly recommended. Nano TiO2 addition in PMMA did not provide any significant advantage in terms of thermal conductivity, but its addition in PMMA is justified because of its mechanical and antimicrobial properties.
Topics: Titanium; Zirconium; Polymethyl Methacrylate; Thermal Conductivity; Nanoparticles; Hot Temperature; Denture Bases; Materials Testing; In Vitro Techniques
PubMed: 38946506
DOI: 10.4103/jips.jips_575_23 -
Journal of Nutritional Science and... 2024Alaska pollack protein (APP), has been reported as a protein source that can enhance muscle hypertrophy more than other protein sources in animal studies. This study... (Randomized Controlled Trial)
Randomized Controlled Trial
Alaska pollack protein (APP), has been reported as a protein source that can enhance muscle hypertrophy more than other protein sources in animal studies. This study aimed to examine the effects of APP ingestion on muscle quantity and quality in young adults. Fifty-five young college students were assigned to two groups: APP and placebo (whey protein: WP) groups, and instructed to ingest 4.5 g of each protein in addition to daily meals, and to maintain their usual daily physical activities for 3 mo. Twenty-one and 23 students completed the intervention and were analyzed in APP and WP groups, respectively. The maximum knee extension torque significantly increased in both groups during the intervention. The motor unit discharge rate, which is an indicator of activation, for a given force level significantly decreased in both groups during the intervention, but its decrease in the APP group was significantly greater than in the WP group. Echo intensity of the vastus lateralis evaluated by ultrasound images significantly decreased in both groups. The muscle thickness and skeletal muscle mass did not change. Small amount of additional APP intake induces greater effects on neural activation than WP, suggesting the greater neural economy of generation of force.
Topics: Humans; Young Adult; Male; Female; Muscle, Skeletal; Dietary Proteins; Adult; Adaptation, Physiological; Gadiformes; Torque; Quadriceps Muscle; Muscle Strength; Double-Blind Method
PubMed: 38945888
DOI: 10.3177/jnsv.70.228 -
Design and optimization of THz coupling in zirconia MAS rotors for dynamic nuclear polarization NMR.Journal of Magnetic Resonance (San... Jun 2024We present 3D electromagnetic simulations of the coupling of a 250 GHz beam to the sample in a 380 MHz DNP NMR spectrometer. To obtain accurate results for magic angle...
We present 3D electromagnetic simulations of the coupling of a 250 GHz beam to the sample in a 380 MHz DNP NMR spectrometer. To obtain accurate results for magic angle spinning (MAS) geometries, we first measured the complex dielectric constants of zirconia, sapphire, and the sample matrix material (DNP juice) from room temperature down to cryogenic temperatures and from 220 to 325 GHz with a VNA and up to 1 THz with a THz TDS system. Simulations of the coupling to the sample were carried out with the ANSYS HFSS code as a function of the rotor wall material (zirconia or sapphire), the rotor wall thickness, and the THz beam focusing (lens or no lens). For a zirconia rotor, the B field in the sample was found to be strongly dependent on the rotor wall thickness, which is attributed to the high refractive index of zirconia. The optimum thickness of the wall is likely due to a transmission maximum but is offset from the thickness predicted by a simple calculation for a flat slab of the wall material. The B value was found to be larger for a sapphire rotor than for a zirconia rotor for all cases studied. The results found in this work provide new insights into the coupling of THz radiation to the sample and should lead to improved designs of future DNP NMR instrumentation.
PubMed: 38943993
DOI: 10.1016/j.jmr.2024.107722 -
Poultry Science Jun 2024This study aimed to investigate the developmental change of body growth and gene expression related to fatty acid uptake and oxidation in the yolk sac membrane (YSM) and...
This study aimed to investigate the developmental change of body growth and gene expression related to fatty acid uptake and oxidation in the yolk sac membrane (YSM) and jejunum during embryogenesis in Muscovy ducks. The weights of embryos and yolk sac (YS) (5 embryos per replicate, n = 6) were recorded on embryonic days (E)16, E19, E22, E25, E28, E31, and the day of hatch (DOH). The fat and fatty acid contents in YSM, jejunal histology, and gene expression related to fatty acid metabolism in YSM and jejunum were determined in each sampling time. Among the nonlinear models, the maximum growth is estimated at 2.83 (E22.5), 2.67 (E22.1), and 2.60 (E21.3) g/d using logistic, Gompertz, and Von Bertalanffy models, respectively. The weight of YS, and ether extract-free YS as well as the amounts of fat and fatty acids in YS decreased (P < 0.05) linearly, whereas the villus height, crypt depth, villus height/crypt depth, and musculature thickness in jejunum increased (P < 0.05) linearly during embryogenesis. The mRNA expression of CD36, SLC27A4, and FABP1 related to fatty acid uptake as well as the mRNA and protein expressions of PPARα and CPT1 related to fatty acid oxidation increased in a quadratic manner (P < 0.05) in both YS and jejunum, and the maximum values were achieved during E25 to E28. In conclusion, the maximum growth rate of Muscovy duck embryos was estimated at 2.60 to 2.83 g/d on E21.3 to E23.5, while the accumulations of lipid and fatty acid in YS were decreased in association with the increased absorptive area of morphological structures in jejunum. The gene and protein expression involved in fatty acid metabolism displayed a similar enhancement pattern between YSM and jejunum during E25 to E28, suggesting that fatty acid utilization could be strengthened to meet the energy demand for embryonic development.
PubMed: 38943802
DOI: 10.1016/j.psj.2024.103929 -
Scientific Reports Jun 2024Subclinical leaflet thrombosis (SLT) can be one of the causes of transcatheter heart valve (THV) failure after transcatheter aortic valve implantation (TAVI). We sought...
Subclinical leaflet thrombosis (SLT) can be one of the causes of transcatheter heart valve (THV) failure after transcatheter aortic valve implantation (TAVI). We sought to clarify the formation process of SLT and thrombogenicity during the perioperative period of TAVI. This multicenter, prospective, single-arm interventional study enrolled 26 patients treated with edoxaban for atrial fibrillation and who underwent TAVI for severe aortic stenosis between September 2018 and September 2022. We investigated changes in maximal leaflet thickness detected by contrast-enhanced computed tomography between 1 week and 3 months after TAVI in 18 patients and measured the thrombogenicity by Total Thrombus-formation Analysis System (T-TAS) and flow stagnation volume by computational fluid dynamics (CFD) (n = 11). SLT was observed in 16.7% (3/18) at 1 week, but decreased to 5.9% (1/17) at 3 months after TAVI. Patients with SLT at 1 week had a significantly decreased maximal leaflet thickness compared to those without SLT. Thrombogenicity assessed by T-TAS decreased markedly at 1 week and tended to increase at 3 months. The stagnation volume assessed by CFD was positively associated with a higher maximum leaflet thickness. This study showed the course of leaflet thrombus formation and visualization of stagnation in neo-sinus of THV in the acute phase after TAVI.
Topics: Humans; Aortic Valve Stenosis; Transcatheter Aortic Valve Replacement; Atrial Fibrillation; Thrombosis; Female; Male; Aged, 80 and over; Aged; Prospective Studies; Aortic Valve; Severity of Illness Index; Pyridines; Thiazoles
PubMed: 38942790
DOI: 10.1038/s41598-024-65600-5 -
World Journal of Nuclear Medicine Jun 2024The purpose of a parallel-hole collimator in a scintillation camera system is to transmit only those photons that have an emission angle close to the direction of...
The purpose of a parallel-hole collimator in a scintillation camera system is to transmit only those photons that have an emission angle close to the direction of the hole. This makes it possible to receive spatial information about the origin of the emission, that is, radioactivity decay. The dimension, shape, and intrahole thickness determine the spatial resolution and, by a tradeoff, sensitivity. The composition of the collimator material also plays an important role in determining a proper collimator. In this study, we compared tungsten alloys as a potential collimator material replacement for the conventional lead antimony material used in most of the current camera systems. Monte Carlo simulations of a commercial scintillation camera system with low energy high resolution (LEHR), medium-energy (ME), and high-energy (HE) collimators of lead, tungsten, and tungsten-based alloy were simulated for different I-131, Lu-177, I-123, and Tc-99m sources, and a Deluxe rod phantom using the SIMIND Monte Carlo code. Planar images were analyzed regarding spatial resolution, image contrast in a cold source case, and system sensitivity for each collimator configuration. The hole dimensions for the three collimators were those specified in the vendor's datasheet. Using Pb, W, and tungsten alloy (Wolfmet) as collimator materials, the full width at half maximum (FWHM) measures for total counts (T) for LEHR with Tc-99m source (6.9, 6.8, and 6.8 mm), for ME with Lu-177 source (11.7, 11.5, and 11.6 mm), and for HE with I-131 (6.2, 13.1, and 13.1 mm) were obtained, and the system sensitivities were calculated as 89.9, 86.1, and 89.8 cps /MBq with Tc-99m source; 42.7, 17.4, and 20.9 cps /MBq with Lu-177 source; and 40.1, 69.7, and 77.4 cps /MBq with I-131 source. The collimators of tungsten and tungsten alloy (97.0% W, 1.5% Fe, 1.5% Ni) provided better spatial resolution and improved image contrast when compared with conventional lead-based collimators. This was due to lower septal penetration. The results suggest that development of a new set of ME and HE tungsten and tungsten alloy collimators could improve imaging of I-131, Lu-177, and I-123.
PubMed: 38933066
DOI: 10.1055/s-0044-1786165 -
Sensors (Basel, Switzerland) Jun 2024Few-layer black phosphorus (FLBP) is a highly promising material for high sensitivity label-free surface plasmon resonance (SPR) sensors due to its exceptional...
Few-layer black phosphorus (FLBP) is a highly promising material for high sensitivity label-free surface plasmon resonance (SPR) sensors due to its exceptional electrical, optical, and mechanical properties. FLBP exhibits inherent anisotropy with different refractive indices along its two main crystal orientations, the zigzag and armchair axes. However, this anisotropic property is often overlooked in FLBP-based sensors. In this study, we conducted a comprehensive investigation of the SPR reflectivity and phase in a BK7-Ag-FLBP structure to understand the influence of the stacking sequence and the number of FLBP layers on the sensing performance. Clear resonant angle shifts caused by different stacking sequences of FLBP could be observed both theoretically and experimentally. In the theoretical study, the highest reflective and phase sensitivities were achieved with a 12-layer black phosphorus (BP) structure. The reflectivity sensitivity reached 287.9°/refractive index units (RIU) with the zz stacking 12-layer BP film exhibiting a sensitivity 76°/RIU higher than the ac stacking structure. Similarly, the phase sensitivity reached 1162°/RIU with the zz stacking 12-layer BP structure showing a sensitivity 276.9°/RIU higher than the ac stacking structure. The electric field distribution of the 12-layer BP structure with four different stacking sequences has also been analyzed. In the experiment study, the well-known Attenuated Total Reflection (ATR) θ-2θ SPR setup is utilized to detect the reflectivity and phase of BK7-Ag-FLBP structures. The FLBP samples with the same thickness but different stacking sequences show significant resonant angle shift (0.275°) and maximum phase difference variation (34.6°). The FLBP sample thickness and crystal orientations have been demonstrated using the angular-resolved polarized Raman spectroscopy (ARPRS). These theoretical and experimental results provide strong evidence that the stacking sequences of FLBP have a significant impact on the sensing performance of SPR sensors. By harnessing the anisotropic properties of materials like FLBP, novel structures of anisotropic-2D material-based SPR sensors could open up exciting possibilities for innovative applications.
PubMed: 38931641
DOI: 10.3390/s24123851 -
Plants (Basel, Switzerland) Jun 2024Water deficiency has been recognized as a major abiotic stress that causes losses in maize crops around the world. The maize crop is very important due to the range of...
Water deficiency has been recognized as a major abiotic stress that causes losses in maize crops around the world. The maize crop is very important due to the range of products that are derived from this plant. A potential way to reduce the damages caused by water deficiency in maize crops is through the association with plant growth-promoting bacteria (PGPB) and arbuscular mycorrhizal fungi (AMF). To define the mechanisms developed by associative PGPB and AMF in maize that are involved in protection against moderate drought (MD), this study evaluated the biometrical, anatomical, biochemical, and physiological parameters of maize grown under MD and inoculated with different PGPB ( strain Ab-V5 and sp. strain ZK) and with AMF. The relative water content did not change in the treatments. The association with ZK increased the shoot:total ratio, total dry weight, maximum quantum yield of photosystem II, vascular cylinder thickness, and vascular cylinder area. The Ab-V5 inoculation led to an increment in root dry weight, the area of metaxylem vessel elements, and nitrate reductase activity. The AMF association did not lead to changes in the measured parameters. The results indicate that the association with PGPB is a relevant alternative to contribute to reducing losses in maize crops under drought. However, AMF is not indicated for this crop under drought.
PubMed: 38931099
DOI: 10.3390/plants13121667 -
Micromachines Jun 2024The surface morphology of perovskite films significantly influences the performance of perovskite light-emitting diodes (PeLEDs). However, the thin perovskite thickness...
The surface morphology of perovskite films significantly influences the performance of perovskite light-emitting diodes (PeLEDs). However, the thin perovskite thickness (~10 nm) results in low surface coverage on the substrate, limiting the improvement of photoelectric performance. Here, we propose a molecular additive strategy that employs (FDPP) molecules as additives. P=O and (5F) on FDPP can coordinate with Pb to slow the crystallization process of perovskite and enhance surface coverage. Moreover, FDPP reduces the defect density of perovskite and enhances the crystalline quality. The maximum brightness, power efficiency (PE), and external quantum efficiency (EQE) of the optimal device reached 24,230 cd m, 82.73 lm W, and 21.06%, respectively. The device maintains an EQE of 19.79% at 1000 cd m and the stability is further enhanced. This study further extends the applicability of P=O-based additives.
PubMed: 38930769
DOI: 10.3390/mi15060799