ABSTRACT
The posterior parietal cortex exhibits choice-selective activity during perceptual decision-making tasks1-10. However, it is not known how this selective activity arises from the underlying synaptic connectivity. Here we combined virtual-reality behaviour, two-photon calcium imaging, high-throughput electron microscopy and circuit modelling to analyse how synaptic connectivity between neurons in the posterior parietal cortex relates to their selective activity. We found that excitatory pyramidal neurons preferentially target inhibitory interneurons with the same selectivity. In turn, inhibitory interneurons preferentially target pyramidal neurons with opposite selectivity, forming an opponent inhibition motif. This motif was present even between neurons with activity peaks in different task epochs. We developed neural-circuit models of the computations performed by these motifs, and found that opponent inhibition between neural populations with opposite selectivity amplifies selective inputs, thereby improving the encoding of trial-type information. The models also predict that opponent inhibition between neurons with activity peaks in different task epochs contributes to creating choice-specific sequential activity. These results provide evidence for how synaptic connectivity in cortical circuits supports a learned decision-making task.
Subject(s)
Decision Making , Neural Pathways , Parietal Lobe , Synapses , Calcium/analysis , Calcium/metabolism , Decision Making/physiology , Interneurons/metabolism , Interneurons/ultrastructure , Learning/physiology , Microscopy, Electron , Neural Inhibition , Neural Pathways/physiology , Neural Pathways/ultrastructure , Parietal Lobe/cytology , Parietal Lobe/physiology , Parietal Lobe/ultrastructure , Pyramidal Cells/metabolism , Pyramidal Cells/ultrastructure , Synapses/metabolism , Synapses/ultrastructure , Virtual Reality , Models, NeurologicalABSTRACT
Digital logic circuits are based on complementary pairs of n- and p-type field effect transistors (FETs) via complementary metal oxide semiconductor technology. In three-dimensional (3D) or bulk semiconductors, substitutional doping of acceptor or donor impurities is used to achieve p- and n-type FETs. However, the controllable p-type doping of low-dimensional semiconductors such as two-dimensional (2D) transition-metal dichalcogenides (TMDs) has proved to be challenging. Although it is possible to achieve high-quality, low-resistance n-type van der Waals (vdW) contacts on 2D TMDs1-5, obtaining p-type devices by evaporating high-work-function metals onto 2D TMDs has not been realized so far. Here we report high-performance p-type devices on single- and few-layered molybdenum disulfide and tungsten diselenide based on industry-compatible electron beam evaporation of high-work-function metals such as palladium and platinum. Using atomic resolution imaging and spectroscopy, we demonstrate near-ideal vdW interfaces without chemical interactions between the 2D TMDs and 3D metals. Electronic transport measurements reveal that the Fermi level is unpinned and p-type FETs based on vdW contacts exhibit low contact resistance of 3.3 kΩ µm, high mobility values of approximately 190 cm2 V-1 s-1 at room temperature, saturation currents in excess of 10-5 A µm-1 and an on/off ratio of 107. We also demonstrate an ultra-thin photovoltaic cell based on n- and p-type vdW contacts with an open circuit voltage of 0.6 V and a power conversion efficiency of 0.82%.
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Autophagy is an important intracellular catabolic mechanism that mediates the degradation of cytoplasmic proteins and organelles. We report a potent small molecule inhibitor of autophagy named "spautin-1" for specific and potent autophagy inhibitor-1. Spautin-1 promotes the degradation of Vps34 PI3 kinase complexes by inhibiting two ubiquitin-specific peptidases, USP10 and USP13, that target the Beclin1 subunit of Vps34 complexes. Beclin1 is a tumor suppressor and frequently monoallelically lost in human cancers. Interestingly, Beclin1 also controls the protein stabilities of USP10 and USP13 by regulating their deubiquitinating activities. Since USP10 mediates the deubiquitination of p53, regulating deubiquitination activity of USP10 and USP13 by Beclin1 provides a mechanism for Beclin1 to control the levels of p53. Our study provides a molecular mechanism involving protein deubiquitination that connects two important tumor suppressors, p53 and Beclin1, and a potent small molecule inhibitor of autophagy as a possible lead compound for developing anticancer drugs.
Subject(s)
Apoptosis Regulatory Proteins/metabolism , Benzylamines/pharmacology , Endopeptidases/metabolism , Quinazolines/pharmacology , Tumor Suppressor Protein p53/metabolism , Ubiquitin Thiolesterase/metabolism , Animals , Autophagy , Beclin-1 , Class III Phosphatidylinositol 3-Kinases/metabolism , Humans , Mice , Ubiquitin-Specific Proteases , UbiquitinationABSTRACT
On the basis of historical influenza and COVID-19 forecasts, we found that more than 3 forecast models are needed to ensure robust ensemble accuracy. Additional models can improve ensemble performance, but with diminishing accuracy returns. This understanding will assist with the design of current and future collaborative infectious disease forecasting efforts.
Subject(s)
COVID-19 , Disease Outbreaks , Forecasting , Influenza, Human , SARS-CoV-2 , Humans , COVID-19/epidemiology , Influenza, Human/epidemiology , Influenza, Human/history , Models, Statistical , Epidemiological ModelsABSTRACT
Carbon black (CB) particles that can absorb from near ultraviolet to infrared rays are well dispersed into an isotropic dielectric liquid and their optical properties can be kept even under exposure to sunlight over a long time. The shutter which controls the position of CB particles by electrophoretic force can be applied to switchable light shutters for windows in buildings and automobiles for the purpose of energy savings. Here, a wideband light shutter with three terminal electrodes is proposed, exhibiting excellent dark (transmittance ≈1.4%) and transparent state (transmittance >60%). The device operates at a low field intensity of about 1 V µm-1 to obtain transparent state and its wide temperature range operation from -50 to 120 °C is confirmed while conventional liquid crystal-based shutter cannot perform such levels due to a limited temperature range in the nematic phase. In addition, haze is minimized in a transparent state by adopting an insulation layer over electrodes and a solution is found to keep a transparent state without applying power. It is believed that the proposed broadband shutter with fast response time could open a new chapter in switchable windows owing to its low power consumption and working in a wide temperature range.
ABSTRACT
The comorbid association of autoimmune diseases with cancers has been a major obstacle to successful anti-cancer treatment. Cancer survival rate decreases significantly in patients with preexisting autoimmunity. However, to date, the molecular and cellular profiles of such comorbidities are poorly understood. We used Aicardi-Goutières syndrome (AGS) as a model autoimmune disease and explored the underlying mechanisms of genome instability in AGS-associated-gene-deficient patient cells. We found that R-loops are highly enriched at transcription-replication conflict regions of the genome in fibroblast of patients bearing SAMHD1 mutation, which is the AGS-associated-gene mutation most frequently reported with tumor and malignancies. In SAMHD1-depleted cells, R-loops accumulated with the concomitant activation of DNA damage responses. Removal of R-loops in SAMHD1 deficiency reduced cellular responses to genome instability. Furthermore, downregulation of SAMHD1 expression is associated with various types of cancer and poor survival rate. Our findings suggest that SAMHD1 functions as a tumor suppressor by resolving R-loops, and thus, SAMHD1 and R-loop may be novel diagnostic markers and targets for patient stratification in anti-cancer therapy.
Subject(s)
Autoimmune Diseases of the Nervous System/genetics , Autoimmune Diseases/genetics , Genomic Instability/genetics , Nervous System Malformations/genetics , SAM Domain and HD Domain-Containing Protein 1/genetics , Autoimmune Diseases/immunology , Autoimmune Diseases/pathology , Autoimmune Diseases of the Nervous System/immunology , Autoimmune Diseases of the Nervous System/pathology , Cell Line, Tumor , DNA Damage/genetics , DNA Replication/genetics , Fibroblasts/metabolism , Genome, Human/genetics , Humans , Mutation/genetics , Neoplasms/genetics , Neoplasms/therapy , Nervous System Malformations/immunology , Nervous System Malformations/pathology , R-Loop Structures/genetics , SAM Domain and HD Domain-Containing Protein 1/ultrastructure , Transcription, Genetic/genetics , TransfectionABSTRACT
BACKGROUND: To discover pharmacotherapy prescription patterns and their statistical associations with outcomes through a clinical pathway inference framework applied to real-world data. METHODS: We apply machine learning steps in our framework using a 2006 to 2020 cohort of veterans with major depressive disorder (MDD). Outpatient antidepressant pharmacy fills, dispensed inpatient antidepressant medications, emergency department visits, self-harm, and all-cause mortality data were extracted from the Department of Veterans Affairs Corporate Data Warehouse. RESULTS: Our MDD cohort consisted of 252,179 individuals. During the study period there were 98,417 emergency department visits, 1,016 cases of self-harm, and 1,507 deaths from all causes. The top ten prescription patterns accounted for 69.3% of the data for individuals starting antidepressants at the fluoxetine equivalent of 20-39 mg. Additionally, we found associations between outcomes and dosage change. CONCLUSIONS: For 252,179 Veterans who served in Iraq and Afghanistan with subsequent MDD noted in their electronic medical records, we documented and described the major pharmacotherapy prescription patterns implemented by Veterans Health Administration providers. Ten patterns accounted for almost 70% of the data. Associations between antidepressant usage and outcomes in observational data may be confounded. The low numbers of adverse events, especially those associated with all-cause mortality, make our calculations imprecise. Furthermore, our outcomes are also indications for both disease and treatment. Despite these limitations, we demonstrate the usefulness of our framework in providing operational insight into clinical practice, and our results underscore the need for increased monitoring during critical points of treatment.
Subject(s)
Depressive Disorder, Major , Veterans , Humans , Depressive Disorder, Major/chemically induced , Depressive Disorder, Major/drug therapy , Antidepressive Agents/therapeutic useABSTRACT
This paper presents the design of a low-noise amplifier (LNA) with a bypass mode for the n77/79 bands in 5G New Radio (NR). The proposed LNA integrates internal matching networks for both input and output, combining two LNAs for the n77 and n79 bands into a single chip. Additionally, a bypass mode is integrated to accommodate the flexible operation of the receiving system in response to varying input signal levels. For each frequency band, we designed a low-noise amplifier for the n77 band to expand the bandwidth to 900 MHz (3.3 GHz to 4.2 GHz) using resistive-capacitance (RC) feedback and series inductive-peaking techniques. For the n79 band, only the RC feedback technique was employed to optimize the performance of the LNA for its 600 MHz bandwidth (4.4 GHz to 5.0 GHz). Because wideband techniques can lead to a trade-off between gain and noise, causing potential degradation in noise performance, appropriate bandwidth design becomes crucial. The designed n77 band low-noise amplifier achieved a simulated gain of 22.6 dB and a noise figure of 1.7 dB. Similarly, the n79 band exhibited a gain of 21.1 dB and a noise figure of 1.5 dB with a current consumption of 10 mA at a 1.2 supply voltage. The bypass mode was designed with S21 of -3.7 dB and -5.0 dB for n77 and n79, respectively.
ABSTRACT
Controlling the in-car environment, including temperature and ventilation, is necessary for a comfortable driving experience. However, it often distracts the driver's attention, potentially causing critical car accidents. In the present study, we implemented an in-car environment control system utilizing a brain-computer interface (BCI) based on steady-state visual evoked potential (SSVEP). In the experiment, four visual stimuli were displayed on a laboratory-made head-up display (HUD). This allowed the participants to control the in-car environment by simply staring at a target visual stimulus, i.e., without pressing a button or averting their eyes from the front. The driving performances in two realistic driving tests-obstacle avoidance and car-following tests-were then compared between the manual control condition and SSVEP-BCI control condition using a driving simulator. In the obstacle avoidance driving test, where participants needed to stop the car when obstacles suddenly appeared, the participants showed significantly shorter response time (1.42 ± 0.26 s) in the SSVEP-BCI control condition than in the manual control condition (1.79 ± 0.27 s). No-response rate, defined as the ratio of obstacles that the participants did not react to, was also significantly lower in the SSVEP-BCI control condition (4.6 ± 14.7%) than in the manual control condition (20.5 ± 25.2%). In the car-following driving test, where the participants were instructed to follow a preceding car that runs at a sinusoidally changing speed, the participants showed significantly lower speed difference with the preceding car in the SSVEP-BCI control condition (15.65 ± 7.04 km/h) than in the manual control condition (19.54 ± 11.51 km/h). The in-car environment control system using SSVEP-based BCI showed a possibility that might contribute to safer driving by keeping the driver's focus on the front and thereby enhancing the overall driving performance.
Subject(s)
Brain-Computer Interfaces , Humans , Automobiles , Evoked Potentials, Visual , Eye , LaboratoriesABSTRACT
Topological textures of ferroelectric polarizations have promise as alternative devices for future information technology. A polarization rotation inevitably deviates from the stable orientation in axial ferroelectrics, but local energy losses compromise the global symmetry, resulting in a distorted shape of the topological vortex or inhibiting the vortex. Easy planar isotropy helps to promote rotating structures and, accordingly, to facilitate access to nontrivial textures. Here, we investigate the domain structure of an epitaxial thin film of bismuth tungsten oxide (Bi2WO6) grown on a (001) SrTiO3 substrate. By using angle-resolved piezoresponse force microscopy and scanning transmission electron microscopy, we find the existence of a hidden phase with ⟨100⟩-oriented ferroelectric polarizations in the middle of the four variant ⟨110⟩-oriented polarization domains, which assists in the formation of flux closure domains. The results suggest that this material is one step closer to becoming an isotropic two-dimensional polar material.
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In the above-mentioned article, it has come to the authors' attention that, during the preparation of Figure 5C and Supplemental Figure S2C for the final version of this article, the authors unintentionally assembled incorrect tubulin immunoblots due to similarities in the markings or names, such as FLT3 versus FT, between two similar experiments. The amended versions of these figures are shown below. Neither the quantitative determinations nor the conclusions of this article are altered. The authors apologize for these errors.
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Background and Objectives: Cervical radiculopathy (CR) manifests as pain and sensorimotor disturbances in the upper extremities, often resulting from nerve root compression due to intervertebral disc herniation, degenerative changes, or trauma. While conservative treatments are initially preferred, persistent or severe cases may require surgical intervention. Ultrasound-guided selective nerve root block (SNRB) has emerged as a promising intervention for alleviating symptoms and potentially obviating the need for surgery. This study evaluates the therapeutic efficacy of ultrasound-guided SNRB in managing chronic CR, aiming to determine its potential in symptom relief and delaying or avoiding surgical procedures. Materials and Methods: A retrospective analysis was conducted on 720 outpatients treated for CR between October 2019 and March 2022. After excluding patients with traumatic CR, previous surgeries, malignancies, progressive neurological symptoms requiring immediate surgery, or inadequate conservative treatment, 92 patients who had experienced cervical radicular pain for more than three months and had failed to improve after more than six weeks of conservative treatment with VAS scores ≥ 5 were included. The patients underwent single or multiple ultrasound-guided SNRB procedures, involving the injection of dexamethasone and lidocaine under real-time ultrasound guidance. Symptom severity was assessed at the baseline, and at 4, 8, and 12 weeks post-procedure using the Visual Analog Scale (VAS). The data collected included age, sex, presence of neck and/or radicular pain, physical examination findings, recurrence of symptoms, improvement in symptoms, and whether surgical intervention was ultimately required. Statistical analyses were performed to identify the factors associated with symptom improvement or recurrence. Results: Significant symptom improvement was observed in 69 (75.0%) participants post-SNRB, with 55 (79.7%) showing improvement at 4 weeks, 11 (15.9%) at 8 weeks, and 3 (4.4%) at 12 weeks. Symptom recurrence, defined by an increase in VAS score accompanied by a pain flare lasting at least 24 h after a pain-free interval of at least one month, was noted in 48 (52.2%) patients. The presence of combined neck and radicular pain was a significant predictor of recurrence (p = 0.008). No significant associations were found between symptom relief and factors such as age, gender, initial pain severity, or MRI findings. Conclusions: Ultrasound-guided SNRB effectively manages chronic CR, providing substantial symptom relief and potentially reducing the need for surgical intervention. This technique offers a promising conservative treatment option, especially given its real-time visualization advantages and minimal radiation exposure.
Subject(s)
Nerve Block , Radiculopathy , Ultrasonography, Interventional , Humans , Female , Male , Middle Aged , Radiculopathy/drug therapy , Retrospective Studies , Nerve Block/methods , Ultrasonography, Interventional/methods , Adult , Treatment Outcome , Pain Measurement/methods , Aged , Lidocaine/administration & dosage , Lidocaine/therapeutic use , Chronic Disease , Dexamethasone/administration & dosage , Dexamethasone/therapeutic useABSTRACT
Fast charging technology for electric vehicles (EVs), offering rapid charging times similar to conventional vehicle refueling, holds promise but faces obstacles owing to kinetic issues within lithium-ion batteries (LIBs). Specifically, the significance of cathode materials in fast charging has grown because Ni-rich cathodes are employed to enhance the energy density of LIBs. Herein, the mechanism behind the loss of fast charging capability of Ni-rich cathodes during extended cycling is investigated through a comparative analysis of Ni-rich cathodes with different microstructures. The results revealed that microcracks and the resultant cathode deterioration significantly compromised the fast charging capability over extended cycling. When thick rocksalt impurity phases form throughout the particles owing to electrolyte infiltration via microcracks, the limited kinetics of Li+ ions create electrochemically unreactive areas under high-current conditions, resulting in the loss of fast charging capability. Hence, preventing microcrack formation by tailoring microstructures is essential to ensure stability in fast charging capability. Understanding the relationship between microcracks and the loss of fast charging capability is essential for developing Ni-rich cathodes that facilitate stable fast charging upon extended cycling, thereby promoting widespread EV adoption.
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Patients with two congenital heart diseases (CHDs), Ebstein's anomaly (EA) and left ventricular noncompaction (LVNC), suffer higher morbidity than either CHD alone. The genetic etiology and pathogenesis of combined EA/LVNC remain largely unknown. We investigated a familial EA/LVNC case associated with a variant (p.R237C) in the gene encoding Kelch-like protein 26 (KLHL26) by differentiating induced pluripotent stem cells (iPSCs) generated from affected and unaffected family members into cardiomyocytes (iPSC-CMs) and assessing iPSC-CM morphology, function, gene expression, and protein abundance. Compared with unaffected iPSC-CMs, CMs containing the KLHL26 (p.R237C) variant exhibited aberrant morphology including distended endo(sarco)plasmic reticulum (ER/SR) and dysmorphic mitochondria and aberrant function that included decreased contractions per minute, altered calcium transients, and increased proliferation. Pathway enrichment analyses based on RNASeq data indicated that the "structural constituent of muscle" pathway was suppressed, whereas the "ER lumen" pathway was activated. Taken together, these findings suggest that iPSC-CMs containing this KLHL26 (p.R237C) variant develop dysregulated ER/SR, calcium signaling, contractility, and proliferation.NEW & NOTEWORTHY We demonstrate here that iPSCs derived from patients with Ebstein's anomaly and left ventricular noncompaction, when differentiated into cardiomyocytes, display significant structural and functional changes that offer insight into disease pathogenesis, including altered ER/SR and mitochondrial morphology, contractility, and calcium signaling.
Subject(s)
Ebstein Anomaly , Induced Pluripotent Stem Cells , Humans , Ebstein Anomaly/genetics , Ebstein Anomaly/metabolism , Ebstein Anomaly/pathology , Induced Pluripotent Stem Cells/metabolism , Myocytes, Cardiac/metabolism , Cell Differentiation , Calcium SignalingABSTRACT
Atomic-scale electrocatalysts greatly improve the performance and efficiency of water splitting but require special adjustments of the supporting structures for anchoring and dispersing metal single atoms. Here, the structural evolution of atomic-scale electrocatalysts for water splitting is reviewed based on different synthetic methods and structural properties that create different environments for electrocatalytic activity. The rate-determining step or intermediate state for hydrogen or oxygen evolution reactions is energetically stabilized by the coordination environment to the single-atom active site from the supporting material. In large-scale practical use, maximizing the loading amount of metal single atoms increases the efficiency of the electrocatalyst and reduces the economic cost. Dual-atom electrocatalysts with two different single-atom active sites react with an increased number of water molecules and reduce the adsorption energy of water derived from the difference in electronegativity between the two metal atoms. In particular, single-atom dimers induce asymmetric active sites that promote the degradation of H2 O to H2 or O2 evolution. Consequently, the structural properties of atomic-scale electrocatalysts clarify the atomic interrelation between the catalytic active sites and the supporting material to achieve maximum efficiency.
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The recent introduction of alkali metal halide catalysts for chemical vapor deposition (CVD) of transition metal dichalcogenides (TMDs) has enabled remarkable two-dimensional (2D) growth. However, the process development and growth mechanism require further exploration to enhance the effects of salts and understand the principles. Herein, simultaneous predeposition of a metal source (MoO3 ) and salt (NaCl) by thermal evaporation is adopted. As a result, remarkable growth behaviors such as promoted 2D growth, easy patterning, and potential diversity of target materials can be achieved. Step-by-step spectroscopy combined with morphological analyses reveals a reaction path for MoS2 growth in which NaCl reacts separately with S and MoO3 to form Na2 SO4 and Na2 Mo2 O7 intermediates, respectively. These intermediates provide a favorable environment for 2D growth, including an enhanced source supply and liquid medium. Consequently, large grains of monolayer MoS2 are formed by self-assembly, indicating the merging of small equilateral triangular grains on the liquid intermediates. This study is expected to serve as an ideal reference for understanding the principles of salt catalysis and evolution of CVD in the preparation of 2D TMDs.
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The precisely tailored refractive index of optical materials is the key to utilizing and manipulating light during its propagation through the matrix, thereby improving their application performances. In this paper, mesoporous metal fluoride films with engineered composition (MgF2 :LaF3 ) are demonstrated to achieve finely tunable refractive indices. These films are prepared using a precursor-derived one-step assembly approach via the simple mixing of precursor solutions (Mg(CF3 OO)2 and La(CF3 OO)3 ); then pores are formed simultaneously during solidification owing to the inherent instability of La(CF3 OO)3 . The mesoporous structures are realized through Mg(CF3 OO)2 and La(CF3 OO)3 ions, which interacted with each other based on their electrostatic forces, providing a wide range of refractive indices (from 1.37 to 1.16 at 633 nm). Furthermore, it is systematically several MgF2(1-x) -LaF3(x) layers with different compositions (x = 0.0, 0.3, and 0.5) to form the graded refractive index coating that is optically consecutive between the substrate and the air for broadband and omnidirectional antireflection. An average transmittance of ≈98.03% (400-1100 nm) is achieved with a peak transmittance of ≈99.04% (at 571 nm), and the average antireflectivity is maintained at ≈15.75% even at an incidence of light of 65° (400-850 nm).
ABSTRACT
AIM: The incidence of fungal sinusitis is increasing; however, its pathophysiology has not been investigated previously. We investigate the effect of periodontitis on the incidence of fungal sinusitis over a 12-year follow-up period using nationwide population-based data. MATERIALS AND METHODS: The periodontitis group was randomly selected from the National Health Insurance Service database. The non-periodontitis group was obtained by propensity score matching considering several variables. The primary end point was the diagnosis of sinonasal fungal balls (SFBs) and invasive fungal sinusitis (IFS). RESULTS: The periodontitis and non-periodontitis groups included 12,442 and 12,442 individuals, respectively. The overall adjusted hazard ratio (aHR) for SFBs in the periodontitis group was 1.46 (p = .002). In subgroup analysis, the aHR for SFBs was 1.59 (p = 0.008) for those with underlying chronic kidney disease (CKD), 1.58 (p = .022) for those with underlying atopic dermatitis, 1.48 (p = .019) for those with chronic obstructive pulmonary disease (COPD), and 1.36 (p = .030) for those with diabetes mellitus (DM), but these values are applicable only when considering the relationship between periodontitis and SFB. The aHR for IFS in the periodontitis group was higher than in the non-periodontitis group (2.80; p = .004). CONCLUSIONS: The risk of SFBs and IFS increased after diagnosis of periodontitis. This trend is often more severe in patients with DM, COPD, or CKD, but this association with underlying diseases is applicable only when considering the association between periodontitis and fungal sinusitis.
Subject(s)
Diabetes Mellitus , Mycoses , Periodontitis , Renal Insufficiency, Chronic , Sinusitis , Humans , Follow-Up Studies , Sinusitis/complications , Sinusitis/microbiology , Mycoses/complications , Mycoses/epidemiology , Diabetes Mellitus/epidemiology , Periodontitis/complications , Renal Insufficiency, Chronic/complications , Retrospective Studies , Risk FactorsABSTRACT
A gecko foot-inspired, mushroom-shaped artificial dry adhesive exploiting intermolecular forces between microstructure and surface has drawn research attention for its strong adhesive force. However, the high pull-off strength corresponding to the adhesive force matters when detaching fragile substrates. In this study, we report a vacuum-powered soft actuator having oblique air chambers and a dry adhesive. The soft actuator performs coupled contraction and twisting by applying negative pneumatic pressure inward and exhibits not only high pull-off strength but also easy detachment. This effective detachment can be achieved thanks to the twisting motion of the soft actuator. The detachment performances of the actuator models are assessed using a 6-degrees-of-freedom robot arm. Results show that the soft actuators exhibit remarkable pull-off strength decrement from ~20 N cm-2 to ~2 N cm-2 due to the twisting. Finally, to verify a feasible application of this study, we utilize the inherent compliance of the actuators and introduce a glass transfer system for which a glass substrate on a slope is gripped by the flexibility of the soft actuators and delivered to the destination without any fracture.
ABSTRACT
This paper presents a low-noise amplifier (LNA) with an integrated input and output matching network designed using RF-SOI technology. This LNA was designed with a resistive feedback topology and an inductive peaking technology to provide 600 MHz of bandwidth in the N79 band (4.4 GHz to 5.0 GHz). Generally, the resistive feedback structure used in broadband applications allows the input and output impedance to be made to satisfy the broadband conditions through low-impedance feedback. However, feedback impedance for excessive broadband characteristics can degrade the noise performance as a consequence. To achieve a better noise performance for a bandwidth of 600 MHz, the paper provided an optimized noise performance by selecting the feedback resistor value optimized for the N79 band. Additionally, an inductive peaking technique was applied to the designed low-noise amplifier to achieve a better optimized output matching network. The designed low-noise amplifier simulated a gain of 20.68 dB and 19.94 dB from 4.4 to 5.0 GHz, with noise figures of 1.57 dB and 1.73 dB, respectively. The input and output matching networks were also integrated, and the power consumption was designed to be 9.95 mA at a supply voltage of 1.2 V.