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1.
Technol Health Care ; 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38968032

ABSTRACT

BACKGROUND: Due to the increasing prevalence of respiratory diseases and the importance of early diagnosis. The need for non-invasive and touchless medical diagnostic solutions has become increasingly crucial in modern healthcare to detect lung abnormalities. OBJECTIVE: Existing methods for lung abnormality detection often rely on invasive and time-consuming procedures limiting their effectiveness in real-time diagnosis. This work introduces a novel Touchless Lung Abnormality (TO-LAB) detection model utilizing universal software radio peripherals (USRP) and machine learning algorithms. METHODS: The TO-LAB model integrates a blood pressure meter and an RGB-D depth-sensing camera to gather individual data without physical contact. Heart rate (HR) is analyzed through image conversion to IPPG signals, while blood pressure (BP) is obtained via analog conversion from the blood pressure meter. This touchless imaging setup facilitates the extraction of essential signal features crucial for respiratory pattern analysis. Advanced computer vision algorithms like Mel-frequency cepstral coefficients (MFCC) and Principal Component Analysis (PCA) process the acquired data to focus on breathing abnormalities. These features are then combined and inputted into a machine learning-based Multi-class SVM for breathing activity analysis. The Multi-class SVM categorizes breathing abnormalities as normal, shallow, or elevated based on the fused features. The efficiency of this TO-LAB model is evaluated with the simulated and real-time data. RESULTS: According to the findings, the proposed TO-LAB model attains the maximum accuracy of 96.15% for real time data; however, the accuracy increases to 99.54% for simulated data for the efficient classification of breathing abnormalities. CONCLUSION: From this analysis, our model attains better results in simulated data but it declines the accuracy while processing with real-time data. Moreover, this work has a significant medical impact since it presents a solution to the problem of gathering enough data during the epidemic to create a realistic model with a large dataset.

2.
Genetics ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38963803

ABSTRACT

Radiotherapy is a key treatment option for a wide variety of human tumors, employed either alone or alongside with other therapeutic interventions. Radiotherapy uses high-energy particles to destroy tumor cells, blocking their ability to divide and proliferate. The effectiveness of radiotherapy is due to genetic and epigenetic factors that determine how tumor cells respond to ionizing radiation. These factors contribute to the establishment of resistance to radiotherapy, which increases the risk of poor clinical prognosis of patients. Although the mechanisms by which tumor cells induce radioresistance are unclear, evidence points out several contributing factors including the overexpression of DNA repair systems, increased levels of reactive oxygen species, alterations in the tumor microenvironment, and enrichment of cancer stem cell populations. In this context, dysregulation of microRNAs or miRNAs, critical regulators of gene expression, may influence how tumors respond to radiation. There is increasing evidence that miRNAs may act as sensitizers or enhancers of radioresistance, regulating key processes such as the DNA damage response and the cell death signaling pathway. Furthermore, expression and activity of miRNAs have shown informative value in overcoming radiotherapy and long-term radiotoxicity, revealing their potential as biomarkers. In this review, we will discuss the molecular mechanisms associated with the response to radiotherapy and highlight the central role of miRNAs in regulating the molecular mechanisms responsible for cellular radioresistance. We will also review radio-miRs, radiotherapy-related miRNAs, either as sensitizers or enhancers of radioresistance that hold promise as biomarkers or pharmacological targets to sensitize radioresistant cells.

3.
J Fr Ophtalmol ; 47(8): 104239, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38964279

ABSTRACT

PURPOSE: Radiation-induced optic neuropathy (RION) is rare but may lead to blindness. The mechanisms by which this occurs include endothelial and neuronal damage, but RION has been assessed very little in the case of extraocular tumors treated with high-energy proton therapy, the use of which is expanding worldwide. We assessed peripapillary microvascular changes by optical coherence tomography angiography (OCT-A) in patients undergoing high-energy proton therapy for para-optic intracranial or head and neck tumors. MATERIALS AND METHODS: In this prospective institutional review board approved study, patients receiving>40Gy_RBE maximal PBT dose to their optic nerve between 2018 and 2020 underwent quantitative OCT-A analyses. ImageJ software was used to assess changes in the peripapillary superficial vascular complex (SVC) using vascular area density (VAD), vessel length density (VLD) and fractal dimension (FDsk). Uni- and multivariate analyses were performed. RESULTS: Of 47 patients (78 eyes) with 29±6 months of follow-up (range 18-42), 29 patients (61.7%) had previously undergone surgery and 18 (32.1%) had microvascular abnormalities prior to proton therapy. Total radiotherapy dose was the most relevant factor in decreased peripapillary microvasculature. Duration of follow-up was associated with lower VAD (P=0.005) and mean retinal nerve fiber layer (RNFLm) thickness also decreased. There was no significant correlation between OCT-A changes and mean visual defect. CONCLUSION: Peripapillary microvasculature changes may occur from tumor compression or surgery and proton therapy for extraocular tumors. OCT-A may provide quantitative and mechanistic insights into RION before the occurrence of clinical symptoms.

4.
Curr Biol ; 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38964317

ABSTRACT

Episodic-like memory in non-human animals represents the behavioral characteristics of human episodic memory-the ability to mentally travel backward in time to "re-live" past experiences. A focus on traditional model species of episodic-like memory may overlook taxa possessing this cognitive ability and consequently its evolution across species. Experiments conducted in the wild have the potential to broaden the scope of episodic-like memory research under the natural conditions in which they evolved. We combine two distinct yet complementary episodic-like memory tasks (the what-where-when memory and incidental encoding paradigms), each targeting a different aspect of human episodic memory, namely the content (what-where-when) and process (incidental encoding), to comprehensively test the memory abilities of wild, free-living, non-caching blue tits (Cyanistes caeruleus) and great tits (Parus major). Automated feeders with custom-built programs allowed for experimental manipulation of spatiotemporal experiences on an individual-level basis. In the what-where-when memory experiment, after learning individualized temporal feeder rules, the birds demonstrated their ability to recall the "what" (food type), "where" (feeder location), and "when" (time since their initial visit of the day) of previous foraging experiences. In the incidental encoding experiment, the birds showed that they were able to encode and recall incidental spatial information regarding previous foraging experiences ("where" test), and juveniles, but not adults, were also able to recall incidentally encoded visual information ("which" test). Consequently, this study presents multiple lines of converging evidence for episodic-like memory in a wild population of generalist foragers, suggesting that episodic-like memory may be more taxonomically widespread than previously assumed.

5.
Data Brief ; 54: 110302, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38962189

ABSTRACT

GNSS signals are vulnerable to spoofing and interference, which poses a threat to the security of critical national infrastructure. GNSS data sets with spoofing and jamming are lacking, which hinders the research of GNSS anti-spoofing and anti-interference techniques. This data article presents a dataset recorded by a low-cost sensor deployed on the balcony at the 5th floor of the Science Hall of Yunnan University (25°3'26'' N, 102°41'55'' E). The sensor suite includes a GNSS antenna, a u-blox GNSS receiver and an embedded computer. In the experiment, interferences including spoofing and jamming were irregularly emitted using a SDR HackRF One and a commercial jammer, respectively. The dataset collected by the receiver consists of two parts: (1) raw data; (2) processed data. The types of the raw data include hardware information, satellite information and receiver parameters of GPS, Campass, Galileo, GLONASS and QZSS systems. The processed data are extracted from the raw data, including the signals, Doppler shift, pseudorange observations, carrier phase, position (latitude, longitude, and altitude), satellite azimuth and elevation angles, etc. The provided datasets are interesting for the GNSS security, anti-jamming and anti-spoofing mechanisms based scientific communities.

6.
World J Surg Oncol ; 22(1): 178, 2024 Jul 06.
Article in English | MEDLINE | ID: mdl-38971793

ABSTRACT

BACKGROUND: Any advantage of performing targeted axillary dissection (TAD) compared to sentinel lymph node (SLN) biopsy (SLNB) is under debate in clinically node-positive (cN+) patients diagnosed with breast cancer. Our objective was to assess the feasibility of the removal of the clipped node (RCN) with TAD or without imaging-guided localisation by SLNB to reduce the residual axillary disease in completion axillary lymph node dissection (cALND) in cN+ breast cancer. METHODS: A combined analysis of two prospective cohorts, including 253 patients who underwent SLNB with/without TAD and with/without ALND following NAC, was performed. Finally, 222 patients (cT1-3N1/ycN0M0) with a clipped lymph node that was radiologically visible were analyzed. RESULTS: Overall, the clipped node was successfully identified in 246 patients (97.2%) by imaging. Of 222 patients, the clipped lymph nodes were non-SLNs in 44 patients (19.8%). Of patients in cohort B (n=129) with TAD, the clipped node was successfully removed by preoperative image-guided localisation, or the clipped lymph node was removed as the SLN as detected on preoperative SPECT-CT. Among patients with ypSLN(+) (n=109), no significant difference was found in non-SLN positivity at cALND between patients with TAD and RCN (41.7% vs. 46.9%, p=0.581). In the subgroup with TAD with axillary lymph node dissection (ALND; n=60), however, patients with a lymph node (LN) ratio (LNR) less than 50% and one metastatic LN in the TAD specimen were found to have significantly decreased non-SLN positivity compared to others (27.6% vs. 54.8%, p=0.032, and 22.2% vs. 50%, p=0.046). CONCLUSIONS: TAD by imaging-guided localisation is feasible with excellent identification rates of the clipped node. This approach has also been found to reduce the additional non-SLN positivity rate to encourage omitting ALND in patients with a low metastatic burden undergoing TAD.


Subject(s)
Axilla , Breast Neoplasms , Lymph Node Excision , Neoadjuvant Therapy , Neoplasm, Residual , Sentinel Lymph Node Biopsy , Humans , Female , Breast Neoplasms/pathology , Breast Neoplasms/surgery , Breast Neoplasms/drug therapy , Breast Neoplasms/diagnostic imaging , Lymph Node Excision/methods , Middle Aged , Neoadjuvant Therapy/methods , Prospective Studies , Adult , Sentinel Lymph Node Biopsy/methods , Aged , Neoplasm, Residual/surgery , Neoplasm, Residual/pathology , Lymph Nodes/pathology , Lymph Nodes/surgery , Lymph Nodes/diagnostic imaging , Follow-Up Studies , Prognosis , Lymphatic Metastasis , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Feasibility Studies
7.
Int J Biol Macromol ; 275(Pt 2): 133717, 2024 Jul 06.
Article in English | MEDLINE | ID: mdl-38977055

ABSTRACT

Tiger nut (TN) is a valuable nutrient and gluten-free tuber. To achieve high-quality TN flour as functional ingredients in food, it is essential to develop effective drying technologies for TN. Five drying methods including natural drying (Control), hot-air drying (HD), radio frequency single drying (RFSD), RF assisted hot-air drying (RFHD), and RF- vacuum drying (RFVD) were selected and compared to determine their effects on physiochemical, structural, and rheological properties of TN flour. Results showed that RF drying (RFD) significantly improved the hydration, oil-absorbing, and antioxidant activity capacity, especially for RFVD. RFHD exhibited greater color (BI = 13.80 ± 0.05 and C = 10.26 ± 0.05) and reducing sugar content (253.50 ± 2.27 mg d.b.) than RFSD and RFVD. The gelatinization temperature, enthalpy value, and particle size (57.30-269.33 µm) of TN flour were reduced. The structural property results indicated that RFD reduced the relative crystallinity and short-range ordering of the flour, altered protein secondary structure, and caused the damaged microstructure in comparison with Control and HD groups. All sample gels exhibited a weak strain overshoot behavior (type III) under large amplitude oscillations, and RFD resulted in a reduced viscoelastic behavior. RFD could be an effective method to produce functional TN flour.

8.
Environ Res ; : 119524, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38972338

ABSTRACT

This review offers a detailed examination of the current landscape of radio frequency (RF) electromagnetic field (EMF) assessment tools, ranging from spectrum analyzers and broadband field meters to area monitors and custom-built devices. The discussion encompasses both standardized and non-standardized measurement protocols, shedding light on the various methods employed in this domain. Furthermore, the review highlights the prevalent use of mobile apps for characterizing 5G-NR radio network data. A growing need for low-cost measurement devices is observed, commonly referred to as "sensors" or "sensor nodes," that are capable of enduring diverse environmental conditions. These sensors play a crucial role in both microenvironmental surveys and individual exposures, enabling stationary, mobile, and personal exposure assessments based on body-worn sensors, across wider geographical areas. This review revealed a notable need for cost-effective and long-lasting sensors, whether for individual exposure assessments, mobile (vehicle-integrated) measurements, or incorporation into distributed sensor networks. However, there is a lack of comprehensive information on existing custom-developed RF-EMF measurement tools, especially in terms of measuring uncertainty. Additionally, there is a need for real-time, fast-sampling solutions to understand the highly irregular temporal variations EMF distribution in next-generation networks. Given the diversity of tools and methods, a comprehensive comparison is crucial to determine the necessary statistical tools for aggregating the available measurement data.

9.
Ultrason Sonochem ; 108: 106980, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38981338

ABSTRACT

To obtain high-quality cherry products, ultrasound (US) combined with five chemical pretreatment techniques were used on cherry prior to radio frequency vacuum drying (RFV), including carboxymethyl cellulose coating (CMC), cellulase (CE), ethanol (EA), isomaltooligosaccharide (IMO), and potassium carbonate + ethyl oleate (PC + AEEO). The effect of different pretreatments (US-CMC, US-CE, US-EA, US-IMO, US-(PC + AEEO)) on the drying characteristics, quality properties, texture, and sensory evaluation of cherries was evaluated. Results showed that the dehydration time and energy consumption were decreased by 4.17 - 20.83 % and 3.22 - 19.34 %, respectively, and the contents of individual sugars, soluble solid, total phenolics (TPC), natural active substances, total flavonoids (TFC), and antioxidant properties (DPPH, ABTS and FRAP) were significantly increased after US combined with five chemical treatments (P < 0.05). Moreover, the pretreatment played important role in improving texture properties and surface color retention in the dried cherries. According to the sensory evaluation analysis, the dehydrated cherries pretreated with US-CMC exhibited the highest overall acceptance, texture, crispness, color, and sweet taste showed lower off-odor, bitter taste and sour taste compared to control and other pretreatments. The findings indicate that US-CMC pretreatment is a promising technique for increasing physicochemical qualities and dehydration rate of samples, which provides a novel strategy to processing of dried cherry.

10.
Endocrine ; 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38982023

ABSTRACT

BACKGROUND: It was essential to identify individuals at high risk of fragility fracture and prevented them due to the significant morbidity, mortality, and economic burden associated with fragility fracture. The quantitative ultrasound (QUS) showed promise in assessing bone structure characteristics and determining the risk of fragility fracture. AIMS: To evaluate the performance of a multi-channel residual network (MResNet) based on ultrasonic radiofrequency (RF) signal to discriminate fragility fractures retrospectively in postmenopausal women, and compared it with the traditional parameter of QUS, speed of sound (SOS), and bone mineral density (BMD) acquired with dual X-ray absorptiometry (DXA). METHODS: Using QUS, RF signal and SOS were acquired for 246 postmenopausal women. An MResNet was utilized, based on the RF signal, to categorize individuals with an elevated risk of fragility fracture. DXA was employed to obtain BMD at the lumbar, hip, and femoral neck. The fracture history of all adult subjects was gathered. Analyzing the odds ratios (OR) and the area under the receiver operator characteristic curves (AUC) was done to evaluate the effectiveness of various methods in discriminating fragility fracture. RESULTS: Among the 246 postmenopausal women, 170 belonged to the non-fracture group, 50 to the vertebral group, and 26 to the non-vertebral fracture group. MResNet was competent to discriminate any fragility fracture (OR = 2.64; AUC = 0.74), Vertebral fracture (OR = 3.02; AUC = 0.77), and non-vertebral fracture (OR = 2.01; AUC = 0.69). After being modified by clinical covariates, the efficiency of MResNet was further improved to OR = 3.31-4.08, AUC = 0.81-0.83 among all fracture groups, which significantly surpassed QUS-SOS (OR = 1.32-1.36; AUC = 0.60) and DXA-BMD (OR = 1.23-2.94; AUC = 0.63-0.76). CONCLUSIONS: This pilot cross-sectional study demonstrates that the MResNet model based on the ultrasonic RF signal shows promising performance in discriminating fragility fractures in postmenopausal women. When incorporating clinical covariates, the efficiency of the modified MResNet is further enhanced, surpassing the performance of QUS-SOS and DXA-BMD in terms of OR and AUC. These findings highlight the potential of the MResNet as a promising approach for fracture risk assessment. Future research should focus on larger and more diverse populations to validate these results and explore its clinical applications.

11.
Heliyon ; 10(11): e32325, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38947435

ABSTRACT

Linearity and intermodulation distortion are very crucial parameters for RFICs design. Therefore, in this work, a detailed comparative analysis on linearity and intermodulation distortion of single metal (SMG) and double metal (DMG) double gate junction less transistor (JLT) is done using TCAD silvaco suite. Furthermore, the effects of temperature fluctuation, gate length variation, and gate material engineering on the linearity performance of both devices are also studied. A few significant figures of merit, including Voltage Intercept Point 2 (VIP2), Voltage Intercept Point 3 (VIP3), Third Order Intercept Power (IIP3), 1 dB Compression Point (P1dB), Third Order Intermodulation Distortion (IMD3), and the transconductance derivative parameters First Order Transconductance (gm1), Second Order Transconductance (gm2), and Third Order Transconductance (gm3) are used to assess the device linearity and intermodulation distortion of SMG and DMG JLT's. The findings show that higher VIP2, VIP3, IIP3, 1-dB compression point and lower gm3, IMD3 values are obtained for the SMG JLT device when compared to its counterpart DMG JLT. SMG JLT, which assures strong linearity and low distortion.

12.
Nano Lett ; 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38981024

ABSTRACT

Cryogenic temperatures are crucial for the operation of semiconductor quantum electronic devices, yet the heating effects induced by microwave or laser signals used for quantum state manipulation can lead to significant temperature variations at the nanoscale. Therefore, probing the temperature of individual devices in working conditions and understanding the thermodynamics are paramount for designing and operating large-scale quantum computing systems. In this study, we demonstrate high-sensitivity fast thermometry in a silicon nanotransistor at cryogenic temperatures using RF reflectometry. Through this method, we explore the thermodynamic processes of the nanotransistor during and after a laser pulse and determine the dominant heat dissipation channels in the few-kelvin temperature range. These insights are important to understand thermal budgets in quantum circuits, with our techniques being compatible with microwave and laser radiation, offering a versatile approach for studying other quantum electronic devices in working conditions.

13.
Chem Biol Interact ; 398: 111089, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38823535

ABSTRACT

Radio-resistant triple negative breast cancer (TNBC) is resistant to conventional drugs and radiation therapy. ortho-topolin riboside (oTR) has been evaluated for its anticancer activity in several types of cancer cells. However, its anti-proliferative activity in radio-resistant TNBC cells has not yet been reported. Therefore, we investigated the anti-proliferative activity of oTR in radio-resistant TNBC cells, and performed metabolome, lipidome, transcriptome, and proteome profiling to reveal the mechanisms of the anticancer activity of oTR. oTR showed cytotoxicity against radio-resistant TNBC cells with an inhibitory concentration (IC50) value of 7.78 µM. Significantly decreased (p value < 0.05) basal and compensatory glycolysis were observed in the oTR-treated group than untreated group. Mitochondrial spare respiratory capacity, which is relevant to cell fitness and flexibility, was significantly decreased (p value < 0.05) in the oTR-treated group. The major metabolic pathways significantly altered by oTR according to metabolome, transcriptome, and proteome profiles were the glycerolipid/glycerophospholipid pathway (log2(FC) of MGLL = -0.13, log2(FC) of acylglycerol lipase = -1.35, log2(FC) of glycerol = -0.81), glycolysis (log2(FC) of EGLN1 = 0.16, log2(FC) of EGLN1 = 0.62, log2(FC) of glucose = -0.76, log2(FC) of lactate = -0.81), and kynurenine pathway (log2(FC) of KYNU = 0.29, log2(FC) of kynureninase = 0.55, log2(FC) of alanine = 0.72). Additionally, proline metabolism (log2(FC) of PYCR1 = -0.17, log2(FC) of proline = -0.73) was significantly altered in the metabolomic and transcriptomic profiles. The MAPK signaling pathway (log2(FC) of CCN1 = -0.15, log2(FC) of CCN family member 1 = -1.02) and Rap 1 signaling pathway (log2(FC) of PARD6B = -0.28, log2(FC) of PAR6B = -3.13) were also significantly altered in transcriptomic and proteomic profiles. The findings of this study revealed that oTR has anticancer activity in radio-resistant TNBC cells by affecting various metabolic pathways, suggesting the potential of oTR as a novel anticancer agent for radio-resistant TNBC patients.


Subject(s)
Antineoplastic Agents , Triple Negative Breast Neoplasms , Humans , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/pathology , Cell Line, Tumor , Antineoplastic Agents/pharmacology , Metabolic Networks and Pathways/drug effects , Female , Cell Proliferation/drug effects , Transcriptome/drug effects , Radiation Tolerance/drug effects , Glycolysis/drug effects , Metabolome/drug effects , Multiomics
14.
Food Res Int ; 190: 114592, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38945611

ABSTRACT

Radio frequency (RF) heating has been proved an alternative roasting method for peanuts, which could effectively degrade aflatoxins and possesses the advantages of greater heating efficiency and penetration depth. This study aimed to investigate the influences of RF roasting on the lipid profile of peanut oil under 150 °C target temperature with varied peanut moisture contents (8.29 % and 20 %) and holding times (0, 7.5, and 15 min), using ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS/MS)-based lipidomics. In total, 2587 lipid species from 35 subclasses were identified. After roasting, the contents of sterol lipid (ST) and subclasses of glycerophospholipids (GPs) and glycoglycerolipids increased significantly, while fatty acid (FA), Oxidized (Ox-) FA, cholesterol (CE), and all subclasses of glycerolipids (GLs) decreased, and 1084 differential lipids were screened. The highest ST and lowest CE contents in peanut oil were achieved by medium roasting (7.5 min). The raise in moisture content of peanut simply affected a few GPs subclasses adversely. Compared with hot air (HA) roasting, RF decelerated lipid oxidation, showing higher levels of diacylglycerol, triacylglycerol and FA, with no additional negative impact and only 69 exclusive differential lipids. During RF roasting, hydrolysis and oxidation of fatty acyl chains into secondary oxides were the central behaviors of lipids transformation. This study could provide insights into the lipid changes and transformation mechanism of peanut oil by RF roasting processing.


Subject(s)
Cooking , Hot Temperature , Lipidomics , Lipids , Peanut Oil , Tandem Mass Spectrometry , Peanut Oil/chemistry , Lipidomics/methods , Cooking/methods , Lipids/analysis , Radio Waves , Arachis/chemistry , Fatty Acids/analysis , Chromatography, High Pressure Liquid , Food Handling/methods , Oxidation-Reduction
15.
Materials (Basel) ; 17(12)2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38930367

ABSTRACT

High-radio-frequency (RF) conductivity is required in advanced electronic materials to reduce the electromagnetic loss and power dissipation of electronic devices. Graphene/copper (Gr/Cu) multilayers possess higher conductivity than silver under direct current conditions. However, their RF conductivity and detailed mechanisms have rarely been evaluated at the micro scale. In this work, the RF conductivity of copper-copper (P-Cu), monolayer-graphene/copper (S-Gr/Cu), and multilayer-graphene/copper (M-Gr/Cu) multilayer structures were evaluated using scanning microwave impedance microscopy (SMIM) and dielectric resonator technique. The results indicated that the order of RF conductivity was M-Gr/Cu < P-Cu < S-Gr/Cu at 3 GHz, contrasting with P-Cu < M-Gr/Cu < S-Gr/Cu at DC condition. Meanwhile, the same trend of M-Gr/Cu < P-Cu < S-Gr/Cu was also observed using the dielectric resonator technique. Based on the conductivity-related Drude model and scattering theory, we believe that the microwave radiation can induce a thermal effect at S-Gr/Cu interfaces, leading to an increasing carrier concentration in S-Gr. In contrast, the intrinsic defects in M-Gr introduce additional carrier scattering, thereby reducing the RF conductivity in M-Gr/Cu. Our research offers a practical foundation for investigating conductive materials under RF conditions.

16.
Micromachines (Basel) ; 15(6)2024 May 29.
Article in English | MEDLINE | ID: mdl-38930692

ABSTRACT

This paper presents a symmetric dual-band multiple-input multiple-output (MIMO) antenna system tailored for fifth-generation (5G) mobile terminals. Operating within the 5G frequency bands N77/N78 (3.4-3.6 GHz) and N79 (4.8-5.0 GHz), the proposed MIMO system achieves high isolation between adjacent antenna elements through slotting and self-decoupling technologies. Antenna elements are strategically positioned on two frames perpendicular to the smartphone's main board. Each antenna element integrates a rectangular microstrip radiator on the inner frame surface, accompanied by a grounded rectangular ring on the outer frame surface. The feed line, situated atop the main board, connects to an external SMA connector located at the main board's bottom. Measurement results reveal isolations exceeding 20 dB for the lower band and 24 dB for the higher band. The fabricated and tested MIMO antenna system demonstrates excellent agreement between simulation and measurement outcomes.

17.
Sensors (Basel) ; 24(12)2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38931496

ABSTRACT

This paper proposes a cognitive radio network (CRN)-based hybrid wideband precoding for maximizing spectral efficiency in millimeter-wave relay-assisted multi-user (MU) multiple-input multiple-output (MIMO) systems. The underlying problem is NP-hard and non-convex due to the joint optimization of hybrid processing components and the constant amplitude constraint imposed by the analog beamformer in the radio frequency (RF) domain. Furthermore, the analog beamforming solution common to all sub-carriers adds another layer of design complexity. Two hybrid beamforming architectures, i.e., mixed and fully connected ones, are taken into account to tackle this problem, considering the decode-and-forward (DF) relay node. To reduce the complexity of the original optimization problem, an attempt is made to decompose it into sub-problems. Leveraging this, each sub-problem is addressed by following a decoupled design methodology. The phase-only beamforming solution is derived to maximize the sum of spectral efficiency, while digital baseband processing components are designed to keep interference within a predefined limit. Computer simulations are conducted by changing system parameters under different accuracy levels of channel-state information (CSI), and the obtained results demonstrate the effectiveness of the proposed technique. Additionally, the mixed structure shows better energy efficiency performance compared to its counterparts and outperforms benchmarks.

18.
Curr Oncol ; 31(6): 3199-3211, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38920726

ABSTRACT

Hepatocellular carcinoma (HCC) is a disease with a poor prognosis, often diagnosed at an advanced stage. Therapeutic options have developed considerably in recent years, particularly with trans-arterial treatments. Systemic treatments have also evolved significantly, with the rise of immune checkpoint inhibitors (ICI) as first-line treatment for advanced HCC. The combination of loco-regional treatments and ICI is opening up new prospects and is the subject of numerous clinical trials. Recently, two global phase 3 trials investigating ICI-based adjuvant combinations have demonstrated improvements in recurrence-free survival or progression-free survival in patients treated with resection, ablation, or trans-arterial chemoembolization. However, mature data and overall survival results are still awaited but will be difficult to interpret. We are at the start of a new era of combinations of loco-regional treatments and immunotherapy. The identification of the best therapeutic strategies and predictive biomarkers is a crucial issue for future standards in clinical practice.


Subject(s)
Carcinoma, Hepatocellular , Immune Checkpoint Inhibitors , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/therapy , Liver Neoplasms/drug therapy , Liver Neoplasms/therapy , Immune Checkpoint Inhibitors/therapeutic use , Combined Modality Therapy , Immunotherapy/methods , Chemoembolization, Therapeutic/methods
19.
Cancer Radiother ; 28(3): 293-307, 2024 Jun.
Article in French | MEDLINE | ID: mdl-38876938

ABSTRACT

PURPOSE: The increased risk of second cancer after prostate radiotherapy is a debated clinical concern. The objective of the study was to assess the risk of occurrence of second cancers after prostate radiation therapy based on the analysis the literature, and to identify potential factors explaining the discrepancies in results between studies. MATERIALS AND METHODS: A review of the literature was carried out, comparing the occurrence of second cancers in patients all presenting with prostate cancer, treated or not by radiation. RESULTS: This review included 30 studies reporting the occurrence of second cancers in 2,112,000 patients treated or monitored for localized prostate cancer, including 1,111,000 by external radiation therapy and 103,000 by brachytherapy. Regarding external radiation therapy, the average follow-up was 7.3years. The majority of studies (80%) involving external radiation therapy, compared to no external radiation therapy, showed an increased risk of second cancers with a hazard ratio ranging from 1.13 to 4.9, depending on the duration of the follow-up. The median time to the occurrence of these second cancers after external radiotherapy ranged from 4 to 6years. An increased risk of second rectal and bladder cancer was observed in 52% and 85% of the studies, respectively. Considering a censoring period of more than 10 years after irradiation, 57% and 100% of the studies found an increased risk of rectal and bladder cancer, without any impact in overall survival. Studies of brachytherapy did not show an increased risk of second cancer. However, these comparative studies, most often old and retrospective, had many methodological biases. CONCLUSION: Despite numerous methodological biases, prostate external radiation therapy appears associated with a moderate increase in the risk of second pelvic cancer, in particular bladder cancer, without impacting survival. Brachytherapy does not increase the risk of a second cancer.


Subject(s)
Brachytherapy , Neoplasms, Radiation-Induced , Neoplasms, Second Primary , Prostatic Neoplasms , Humans , Male , Prostatic Neoplasms/radiotherapy , Neoplasms, Second Primary/etiology , Neoplasms, Second Primary/epidemiology , Neoplasms, Radiation-Induced/etiology , Neoplasms, Radiation-Induced/epidemiology , Brachytherapy/adverse effects , Brachytherapy/methods , Urinary Bladder Neoplasms/radiotherapy , Urinary Bladder Neoplasms/etiology , Rectal Neoplasms/radiotherapy , Rectal Neoplasms/etiology
20.
Sensors (Basel) ; 24(11)2024 May 28.
Article in English | MEDLINE | ID: mdl-38894257

ABSTRACT

In the face of rising population, erratic climate, resource depletion, and increased exposure to natural hazards, environmental monitoring is increasingly important. Satellite data form most of our observations of Earth. On-the-ground observations based on in situ sensor systems are crucial for these remote measurements to be dependable. Providing open-source options to rapidly prototype environmental datalogging systems allows quick advancement of research and monitoring programs. This paper introduces Loom, a development environment for low-power Arduino-programmable microcontrollers. Loom accommodates a range of integrated components including sensors, various datalogging formats, internet connectivity (including Wi-Fi and 4G Long Term Evolution (LTE)), radio telemetry, timing mechanisms, debugging information, and power conservation functions. Additionally, Loom includes unique applications for science, technology, engineering, and mathematics (STEM) education. By establishing modular, reconfigurable, and extensible functionality across components, Loom reduces development time for prototyping new systems. Bug fixes and optimizations achieved in one project benefit all projects that use Loom, enhancing efficiency. Although not a one-size-fits-all solution, this approach has empowered a small group of developers to support larger multidisciplinary teams designing diverse environmental sensing applications for water, soil, atmosphere, agriculture, environmental hazards, scientific monitoring, and education. This paper not only outlines the system design but also discusses alternative approaches explored and key decision points in Loom's development.

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