Fine Control Research Articles

Meta-analysis of a Moderate-to-Vigorous Physical Activity Intervention for Academic Achievement in Children and Adolescents.

To analyze the intervention effect of moderate-to-vigorous physical activity (MVPA) on the academic performance of children and adolescents. Experimental studies on the effects of MVPA on the academic performance of children and adolescents were comprehensively searched in Web of Science, China Knowledge Network and other databases, and the Cochrane Risk of Bias Assessment Tool was used to assess the quality of the literature, and the Meta-analysis was performed by Review Manager 5.3. 1) A total of 11 high-quality literature were included, including 4552 subjects; 2) MVPA had a positive effect on the academic performance of children and adolescents (SMD=0.24; 95%CI:0.13, 0.35, P<0.0001), with differences in the effect of different subjects, and the mathematics has the best effect (SMD=0.23; 95%CI:0.11, 0.34, P≤0.0001), followed by reading (SMD=0.24; 95% CI:0.02, 0.46, P<0.05), and the comprehensive achievement intervention effect was not significant (SMD=0.33; 95% CI:-0.15, 0.80, P=0.18); 3) MVPA has the greatest impact on children aged 9-11 years (SMD=0.30; 95%CI:0.06, 0.54, P<0.05); 4) The optimal dose of intervention for MVPA is a long cycle of 30-60 minutes per session(SMD=0.34; 95%CI:0.12, 0.56, P<0.01), 2 times per week(SMD=0.28; 95%CI:0.2, 0.35, P<0.001); 5) The effect of literature publication bias detection was positive. 1) MVPA has a moderate effect on promoting academic achievement in children and adolescents, with younger age groups often benefiting more than older adolescents due to age-related cognitive plasticity; 2) MVPA has limited intervention effect on the performance of other subjects, which leads to the unsatisfactory effect of the intervention on the comprehensive performance; 3) Attention should be paid to the fine control of the intensity of the physical activity to guarantee individual MVPA participation to promote the academic achievement of children and adolescents; 4) Long-term participation, 30-60 minutes per session, 2-3 times per week of MVPA has been shown to be an effective intervention dose to enhance academic performance.

Harnessing coupled nanolasers near exceptional points for directional emission.

Tailoring the losses of optical systems within the frame of non-Hermitian physics has appeared very fruitful in the past few years. In particular, the description of exceptional points (EPs) with coupled resonators has become widespread. The on-chip realization of these functionalities is crucial for integrated nanophotonics but requires fine control techniques of the nanodevice properties. Here, we demonstrate pump-controlled directional emission of two coupled nanolasers that distantly interact via an integrated waveguide. This coupling scheme unusually enables both frequency and loss couplings between two cavities, which can be advantageously exploited to reach EPs by either detuning the cavities or controlling the gain of nanolasers. The system can be readily reconfigured from bidirectional to unidirectional emission by adjusting the pump power.

Research Trends in the Development of Block Copolymer-Based Biosensing Platforms

Biosensing technology, which aims to measure and control the signals of biological substances, has recently been developed rapidly due to increasing concerns about health and the environment. Top–down technologies have been used mainly with a focus on reducing the size of biomaterials to the nano-level. However, bottom–up technologies such as self-assembly can provide more opportunities to molecular-level arrangements such as directionality and the shape of biomaterials. In particular, block copolymers (BCPs) and their self-assembly have been significantly explored as an effective means of bottom–up technologies to achieve recent advances in molecular-level fine control and imaging technology. BCPs have been widely used in various biosensing research fields because they can artificially control highly complex nano-scale structures in a directionally controlled manner, and future application research based on interactions with biomolecules according to the development and synthesis of new BCP structures is greatly anticipated. Here, we comprehensively discuss the basic principles of BCPs technology, the current status of their applications in biosensing technology, and their limitations and future prospects. Rather than discussing a specific field in depth, this study comprehensively covers the overall content of BCPs as a biosensing platform, and through this, we hope to increase researchers’ understanding of adjacent research fields and provide research inspiration, thereby bringing about great advances in the relevant research fields.

Lights on the Synthesis of Surfactant-Free Colloidal Gold Nanoparticles in Alkaline Mixtures of Alcohols and Water.

Surfactant-free colloidal syntheses in aqueous media are attractive to develop nanomaterials relevant for various applications, e. g. catalysis or medicine. However, controlled green syntheses without surfactants of metal nanoparticles in aqueous media remain scarce. Here, room temperature syntheses of gold (Au) nanoparticles (NPs) that require only HAuCl4, alkaline water and an alcohol, i. e. relatively benign chemicals and mild reaction conditions, are developed. The findings of a comprehensive multi-parameters screening performed in small volumes (<3 mL) over 1000+ experiments pave the way to greener high throughput screenings of large parametric spaces and lead to scalable (100 mL) synthetic strategies. A rational selection of the alcohol is proposed. The influence of lights with defined wavelengths (222-690 nm) is investigated. It is found that lights with lower wavelengths favor the formation of smaller 5 nm NPs. Different kinetics and formation pathways are observed for different alcohols and for lights with different wavelengths. The sensitivity to various experimental parameters increases with the alcohol used in the order glycerol<ethylene glycol<ethanol<methanol. New strategies for a rational fine size control, and to some extend shape control, are identified. The results lead to more sustainable and reproducible surfactant-free colloidal syntheses of NPs.

Physical and Chemical Dual Confinement Promotes Controllable Synthesis of Loose-Structured Azine-Linked Nanofilms for Fast Molecular Separation.

Thin-film composite (TFC) membranes, featuring nanoscale film thickness and customizable pore structures, hold promise for solute-solute separations. However, achieving on-demand molecular sieving requires fine control over the membrane microstructure. Here, the concept of physical and chemical dual confinement (PCDC) is introduced to fabricate loose-structured TFC membranes via confined interfacial polymerization (IP). This concept leverages the synergistic effects of physically restricted monomer diffusion and a chemically inhibited reaction to achieve controlled nanofilm growth. Dorsal addition of the aqueous phase to the hydrogel reduces the diamine diffusion via electrostatic and H-bonding interactions within its nanopores. The prepassivation of hydrazine using acid protonation effectively weakens its ability for nucleophilic reactivity. This confined IP between twisted TFPA and short-chain hydrazine yielded loosely structured azine-linked nanofilms, which displayed a high permeability of 53.4 LMH bar-1 and effective differentiation of binary mixtures. This PCDC concept offers a useful guideline to finely tailor polymeric nanofilms for precise separations.

MORPHOLOGICAL AND OPTICAL PROPERTIES OF ZNO NANORODS GROWN ONTO SILICON SUBSTRATES: THE IMPACT OF GROWTH TEMPERATURE

ZnO nanorods (NRs) have been successfully grown onto Silicon (Si) substrates. The properties of ZnO NRs have been characterized using field emission scanning microscopy, Photoluminescence, and X-ray diffraction. Results showed that the growth temperature (85, 90, 95, and 100oC) significantly affected the properties of ZnO NRs. At a temperature of 95oC, the structural and optical properties have been significantly enhanced, besides, well-aligned ZnO NRs have been obtained. With the rise of growth temperature from 85 to 95oC, the crystallite size increases (52 to 94 nm), and the near band edge emission to deep level emission ratio is enhanced. Besides, the aspect ratio for the prepared ZnO NRs has increased significantly reaching 19.42. This study emphasizes the significance of growth temperature in tunning the structural and microstructural and subsequently the physicochemical properties of ZnO NRs by fine control of the growth temperature. Moreover, a facile and cost-efficient method for fabricating ZnO nanorods for electronic applications based on silicon is presented in this study.

Flexible Supercapacitor Device Based on Laser‐Synthesized Nanographene for Low‐Power Applications

Laser‐induced graphene (LIG) and laser‐induced reduced graphene oxide (LIrGO) are two relatively recent graphene‐based nanoscale materials suitable for miniaturized flexible supercapacitors. This study employs direct laser engraving techniques to generate patterns on flexible substrates, such as paper and polyamide (PI). This methodology allows fine control over the formed nanographene structures to fabricated LIG and LIrGO supercapacitors. The LIG on PI exhibits a distinctive porous structure and high surface area, adsorption, and transportation of ions. Furthermore, paper‐based LIrGO electrodes are recyclable and are formed in a single step. The morphological study is done using scanning electron microscopy, Raman spectroscopy, X‐ray photoelectron spectroscopy, and X‐ray diffraction. Galvanostatic charge–discharge studies at 0.05 mA cm−2 current density show an areal capacitance of 3.69 mF cm−2 for LIG and 1.61 mF cm−2 for LIrGO. The comparable energy densities for LIG and LIrGO are 0.32 and 0.16 μWh cm−2, respectively. From the calculative analysis of both types, the variation in specific areal capacitance enabling effective is 56.3% from GCD, indicating that the LIG device performs better. Finally, a portable potentiostat is employed to investigate the viability of utilizing supercapacitors to operate self‐powered sensors in a portable and integrable fashion.

Biogenic and risk elements in wild boar testes and relation to spermatozoa motility

Environmental pollution results in serious health hazards to animals, reflected in biogenic and risk element concentrations in animal tissues. The objective of this study was to examinate concentration of selected elements in testes, and epididymal spermatozoa motility of wild boars. Wild boars were hunted in region Žuhračka - Levice, Slovak Republic. Testes were removed postmortem, spermatozoa were collected from cauda epididymis and assessed by CASA system. Elements concentrations were measured by ICP and by CV-AAS. Spermatozoa motility was 44.29% and progressive motility 18.47%. Concentration of elements in testes was in following order: K > Na > Mg > Ca > Fe > Zn > Al > Cu > Se > Mn > As > Cr > Pb > Mo > Sr > Ni > Ba > Cd > Li > Hg. The most notable correlations indicate association between Se and total spermatozoa motility, as well as with progressive motility, furthermore between As and velocity curved line and beat cross frequency. A high positive significant correlation was found between mercury and beat cross frequency. The data may serve as a fine control indicator to detect potentially toxic elements accumulated from polluted environment that can affect reproduction of wild animals.

Water-assisted preparation of Ni/La(OH)3 catalyst for efficient catalytic C-O bond hydrogenolysis of tetrahydrofuran-dimethanol

Due to easy dehydration of La(OH)3 to LaOOH by thermal treatment, it is challenging to prepare highly efficient Ni/La(OH)3 catalyst for hydrogenolysis reactions. Herein, Ni/La(OH)3 (Ni/La-2) catalyst is prepared by thermal reduction of NiO/La(OH)3 in hydrogen flow with vaporized water, while La(OH)3 is partially dehydrated to LaOOH without water vapor affording Ni/(La(OH)3 + LaOOH) (Ni/La-1). Ni/La-2 displays 93 % and 3 % yields of 1,2,6-hexanetriol (HTO) and 1,6-hexanediol (HDO) respectively towards C-O hydrogenolysis of tetrahydrofuran-dimethanol (THFDM) in batch reactor and high stability (200 h) in fixed-bed reactor, which is the best among the reported catalysts to the best of our knowledge. Ni/La-2 possesses pure La(OH)3 as support, enhanced dispersion of Ni species and abundant Niδ+-O-La interfaces in comparison to Ni/La-1, which results in the exceptional catalytic performances in C-O hydrogenolysis of THFDM. A fine control of reaction temperature and time is required to optimize the yields HTO and HDO in hydrogenolysis of THFDM over Ni/La-2. The water-assisted preparation method provides a new perspective for the preparation of La(OH)3 supported metal catalysts.

Plasmonic Nanocubes with a Controllable "Crescent Arc" Facet: Tunable Hotspot Engineering for Highly Reliable and Sensitive SERS Detection.

The fine control of the nanogap and morphology of metal nanoparticles (NPs) has always been an obstacle, hindering the development and application of surface-enhanced Raman scattering (SERS) quantitative detection. Here, Au/4-mercaptobenzoic acid@Ag@Au-Ag bimetal core-shell nanocubes (NCs) with a "crescent arc" facet (C-Au/4MBA@Ag NCs) as a highly reliable and sensitive surface-enhanced Raman scattering SERS substrate is proposed for the first time. The bifunctional internal standard (IS) molecules (4MBA) govern the morphology of metal shells to maintain cubic configuration and provide calibration for SERS signals' flotation. In parallel, the controllable curvature of the C-Au/4MBA@Ag NCs is directly modulated by adjusting the relative rates of the galvanic replacement and co-reduction reaction, which generates a controllable interparticle nanogap to offer large depositing spaces for analytes and improve authoritative SERS signals' enhancement. The proposed C-Au/4MBA@Ag NCs exhibit an enhancement factor of up to 4.8 × 1010 and contribute to the ultralow RSD (7.9%). These C-Au/4MBA@Ag NCs also enable the detection of hazardous pesticide residues such as methamidophos and thiram in herbal plants with a complex matrix, with an average detection accuracy of up to 96%. In summary, this study achieves a fine control strategy of the "crescent arc" surface for improving SERS performance and explores the practical application potential for accurate and sensitive Raman detection of hazardous substances.

Intense and Stable Blue Light Emission From CsPbBr3/Cs4PbBr6 Heterostructures Embedded in Transparent Nanoporous Films

AbstractLead halide perovskite nanocrystals are attractive for light emitting devices both as electroluminescent and color‐converting materials since they combine intense and narrow emissions with good charge injection and transport properties. However, while most perovskite nanocrystals shine at green and red wavelengths, the observation of intense and stable blue emission still remains a challenging target. In this work, a method is reported to attain intense and enduring blue emission (470–480 nm), with a photoluminescence quantum yield (PLQY) of 40%, originating from very small CsPbBr3 nanocrystals (diameter &lt; 3 nm) formed by controllably exposing Cs4PbBr6 to humidity. This process is mediated by the void network of a mesoporous transparent scaffold in which the zero‐dimensional Cs4PbBr6 lattice is embedded, which allows the fine control over water adsorption and condensation that determines the optimization of the synthetic procedure and, eventually, the nanocrystal size. The approach provides a means to attain highly efficient transparent and stable blue light‐emitting films that complete the palette offered by perovskite nanocrystals for lighting and display applications.

Fine structure control of Fe3O4/ Fe2O3 film by Nitridation-Oxidation-Reduction treatment and high corrosion resistance

The nitriding post-oxidation composite treatment is clean and pollution-free, and the high corrosion resistance of the modified layer has aroused extensive research interest. The phase composition and microstructure of Fe3O4/Fe2O3 film are key factors determining corrosion resistance. We propose a Nitridation-Oxidation-Reduction (NOR) treatment technology nitriding followed by oxidation treatment and then reduction treatment. The precise phase composition and microstructure of the oxide film were characterized and analyzed, and the corrosion resistance of the oxide film was evaluated. Through reduction treatment, the Fe3O4 phase content increased from 54.95 % to 84.75 %, the corrosion potential increased by 0.07 V and the corrosion current density decreased by 2.06 × 10-6A. After NOR treatment, the oxide film has extremely high corrosion resistance, which will have important theoretical and engineering application value.

ER-mitochondria distance is a critical parameter for efficient mitochondrial Ca2+ uptake and oxidative metabolism

IP3 receptor (IP3R)-mediated Ca2+ transfer at the mitochondria-endoplasmic reticulum (ER) contact sites (MERCS) drives mitochondrial Ca2+ uptake and oxidative metabolism and is linked to different pathologies, including Parkinson’s disease (PD). The dependence of Ca2+ transfer efficiency on the ER-mitochondria distance remains unexplored. Employing molecular rulers that stabilize ER-mitochondrial distances at 5 nm resolution, and using genetically encoded Ca2+ indicators targeting the ER lumen and the sub-mitochondrial compartments, we now show that a distance of ~20 nm is optimal for Ca2+ transfer and mitochondrial oxidative metabolism due to enrichment of IP3R at MERCS. In human iPSC-derived astrocytes from PD patients, 20 nm MERCS were specifically reduced, which correlated with a reduction of mitochondrial Ca2+ uptake. Stabilization of the ER-mitochondrial interaction at 20 nm, but not at 10 nm, fully rescued mitochondrial Ca2+ uptake in PD astrocytes. Our work determines with precision the optimal distance for Ca2+ flux between ER and mitochondria and suggests a new paradigm for fine control over mitochondrial function.

Ultrapure gold recovery from electronic waste as nanoparticles immobilized in hydrogel matrix

Solid-supported gold nanoparticles possess significant value as economical and eco-friendly catalysts due to their durability and reusability. Conventional methods to synthesize heterogeneous catalysts require the use of expensive gold precursors, diminishing their economic viability. Recovering gold directly as nanoparticles immobilized in a solid matrix from electronic waste (e-waste) provides a promising economic solution. However, the greater abundance of other metal ions in e-waste solutions makes this task challenging, demanding more selective approaches. This study presents a cost-effective one-pot synthesis of gold nanoparticles immobilized in a hydrogel matrix from e-waste solutions, circumventing the need for gold precursors. The fabricated hydrogel exhibits exceptionally selective gold reduction, producing well-distributed and highly pure (23.78 K) gold nanoparticles inside the hydrogel matrix. The fine control in nanoparticle diameters from 22 to 35 nm was achieved by tuning the monomer compositions of the hydrogel. These hydrogel-supported gold nanoparticles demonstrate reusable catalytic properties, indicating their potential sustainability and industrial compatibility. This approach addresses the economic challenges of synthesizing solid-supported gold nanoparticles and offers a sustainable pathway.

Resonant tunneling properties of laser dressed hyperbolic Pöschl-Teller double barrier potential

We examine the resonant tunneling properties of the laser-dressed hyperbolic Pöschl-Teller double quantum barrier structure. We use the non-equilibrium Green's function method to investigate structure parameters and electric field bias on the transmission properties of the system. The transmission probabilities and resonance energy levels are significantly influenced by the well widths and barrier heights. The barrier height increases, resonance energy levels shift toward higher values, and the resonance peak width narrows, leading to sharper and more selective tunneling behavior. Our results show that increasing the electric field bias leads to a decrease in the transmission probability at the first resonance peak, but this effect is not as strong for the subsequent peaks. Moreover, we find that changes in the laser field's parameter and structure parameters allow for fine control over the electronic spectra, allowing for modifications like red or blue shifts based on particular needs. The significance of comprehending the interaction among structural factors, external fields, and transmission qualities in quantum barrier structures is highlighted by our research, providing valuable information for the development and enhancement of electronic and optoelectronic systems with customized functionality. Our findings show the laser field has a considerable impact on resonant tunneling properties, opening the door to new device applications.

6766 Cortisol Pumps: Hospitalizations And Quality Of Life

Abstract Disclosure: A. Tiwari: None. R. Berry: None. A. Mokbel: None. A. Abotouk: None. A.R. Alrifai: None. J. Waleed: None. O. Alzohaili: None. Introduction: Oral regimens of exogenous cortisol fail to mimic physiologic levels. The discrepancy leads to complications, notably nausea, hyperglycemia, and susceptibility to infection. Finer control over cortisol delivery may be achievable with infusion pumps. While international groups have published their experiences with cortisol pumps, these studies often include less than ten patients. We share the largest, single-center cohort ever documented and the first from an American clinic. Methods: We conducted a retrospective cohort study. Through chart review, we identified all patients who received a cortisol pump at a private clinic; these pumps were originally designed to deliver insulin, but we repurposed them for patients with adrenal insufficiency. Clinic notes allowed collection of cortisol dosing pre- and post-exposure to the cortisol pump. We supplemented this information with telephone and digital surveys on the frequency of hospitalization, symptoms, and quality of life; patients provided verbal consent before participation. A Wilcoxon signed rank test and Fisher exact test evaluated significant differences between groups. Results: We identified thirty patients who received a cortisol infusion pump. Our study revealed a statistically significant decrease in hospitalization rate after exposure to a cortisol pump (n=26, mean difference = -5.94 hospitalizations per year, p=0.003), a decrease in the frequency of fatigue (n=25, p=0.0001) and a decrease in the frequency of hypotension (n=25, p=0.005). A validated, quality of life survey corroborated these findings with improvement in twenty-seven out of twenty-eight questions (n=22, p&amp;lt;0.05). However, we did not detect a statistically significant difference in the frequency of eighteen other symptoms nor cortisol dosing between pre- and post-exposure groups. Conclusion: Infusion pumps can better mimic physiological variations in cortisol than oral dosing regimens. We show the extent to which cortisol dosing may reduce hospitalization rate - and therefore cost - as well as improve quality of life. We hope our findings encourage the availability of infusion pumps for adrenal insufficiency, a smaller market that may not otherwise attract commercial investment for a dedicated, randomized trial. Presentation: 6/3/2024

Multi-stage and multi-colour liquid crystal reflections using a chiral triptycene photoswitchable dopant.

The photomodulation of the helical pitch of cholesteric liquid crystals results in dynamic and coloured canvases that can potentially be used in applications ranging from energy-efficient displays to colour filters, anti-counterfeiting tags and liquid crystal (LC) lasers. Here we report on the analysis of a series of photoswitchable chiral dopants that combine the large geometrical change and bistability of hydrazone switches with the efficient helical pitch induction of the chiral motif, triptycene. We elucidate the effects that conformational flexibility, dispersion forces and π-π interactions have on the chirality transfer ability of the dopant. We then use the irradiation time with visible light (442 nm) combined with a simple digital light processing microscope projection set-up to draw numerous stable multi-coloured images on an LC canvas, showcasing the fine control this dopant yields over the LC assembly.

Feasibility Theory and Practice of CO2-EOR in High CO2-Content Near-saturated Edge-bottom Water Reservoir

Abstract CO2-EOR technology for low-permeability tight oil and gas reservoir is in the ascendant, and CO2-EOR technology for old oilfields has not been paid enough attention, but the implementation scale has great potential, and the expected effect and implementation conditions are good. The feasibility of CO2-EOR technology in the ultra-high water cut stage of high CO2 content, near saturation pressure and edge-bottom water reservoir was studied theoretically, and the field implementation effect was tracked and evaluated. Via petrophysics, reservoir engineering, and site case analysis, a relatively comprehensive reservoir numerical model was developed, clarifying the impact of periodic gas injection volume, gas injection rate, soak time and liquid production rate on the production effect of CO2 huff and puff were clarified. The key injection-production parameters of CO2 huff and puff test wells were designed, and the feasibility study progress of CO2-EOR in near-saturated edge-bottom water reservoirs with high CO2 content was summarized. The theoretical research shows that the change rules of gas-water dual-drive, CO2 water control and oil increase in the process of CO2 huff and puff in high CO2 near-saturated edge and bottom water reservoirs, and reveals the synergistic mechanism of CO2 huff and puff to suppress water and increase energy. The tracking evaluation shows that the sweep condition of CO2 after huff and puff in the test well is complex, the storage ratio is in the range of 40%-70%, the stage oil increase is in the range of 700t-3000t, and the optimized oil increase and oil change rate can reach 2.7t/t. Based on the comprehensive theory and practice, it is considered that CO2-EOR has good potential for high CO2 near-saturated edge and bottom water reservoirs under fine control. This study has guiding and reference significance for CO2-EOR technology and application in similar oilfields at home and abroad.

A 'Fingerprint' of fine motor control maturation: motor development descriptors and reference development bands in primary school children

A 'Fingerprint' of fine motor control maturation: motor development descriptors and reference development bands in primary school children

Accurate neural control of a hand prosthesis by posture-related activity in the primate grasping circuit.

Brain-computer interfaces (BCIs) have the potential to restore hand movement for people with paralysis, but current devices still lack the fine control required to interact with objects of daily living. Following our understanding of cortical activity during arm reaches, hand BCI studies have focused primarily on velocity control. However, mounting evidence suggests that posture, and not velocity, dominates in hand-related areas. To explore whether this signal can causally control a prosthesis, we developed a BCI training paradigm centered on the reproduction of posture transitions. Monkeys trained with this protocol were able to control a multidimensional hand prosthesis with high accuracy, including execution of the very intricate precision grip. Analysis revealed that the posture signal in the target grasping areas was the main contributor to control. We present, for the first time, neural posture control of a multidimensional hand prosthesis, opening the door for future interfaces to leverage this additional information channel.