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1.
Article in English | MEDLINE | ID: mdl-39378129

ABSTRACT

OBJECTIVES: Our objective was to assess the incidence and reason of last-minute cancellations before surgery for lung cancer and their association with outcomes. METHODS: Retrospective analysis on all consecutive patients booked for elective lung cancer surgery from January 2017 through December 2022 in a single centre.Last minute cancellation: a cancellation occurring within the last 24 hours from the planned operation. Cancellation categories: process-related and patient-related.The short-term and long-term outcomes of patients who experienced a last-minute cancellation were analysed. RESULTS: 197 patients of 1587 (12%) had a last-minute cancellation: 156 (79%) were process-related and 41 (21%) were patient-related.3% (5/156) of patients cancelled for process reasons did not receive surgery vs 39% (16/41) of those cancelled for patient-related reasons, p < 0.0001.The 90-day mortality rates of cancelled and non-cancelled patients were similar (4.6% vs 4.7%, p = 1).Five-year overall survival of patients with cancellation was 58% (95% CI 49-66) vs 69% (95% CI 66-71) of those without cancellations, p = 0.022.Among those who had a cancellation, the 5-year OS of those with process-related cancellations was 61% (52-60) vs 35% (14-58) of those with patient-related cancellations (adjusted p value for multiple comparisons = 0.14).Cox regression analysis showed that surgery cancellations within the last 24 hours for patient-related (HR 1.87, 95% CI 1.02-3.42, p = 0.043) reasons remained a factor associated with poorer overall survival after adjusting for clinical stage, type of operation and patient related variables. CONCLUSIONS: Implementing the patient's preoperative clinical evaluation to reduce the occurrence of related last-minute cancellations might mitigate its negative impact on survival.

2.
NMR Biomed ; : e5268, 2024 Oct 07.
Article in English | MEDLINE | ID: mdl-39375036

ABSTRACT

Low magnetic field magnetic resonance imaging (MRI) ( B 0 $$ {B}_0 $$  < 1 T) is regaining interest in the magnetic resonance (MR) community as a complementary, more flexible, and cost-effective approach to MRI diagnosis. Yet, the impaired signal-to-noise ratio (SNR) per square root of time, or SNR efficiency, leading in turn to prolonged acquisition times, still challenges its relevance at the clinical level. To address this, researchers investigate various hardware and software solutions to improve SNR efficiency at low field, including the leveraging of latest advances in computing hardware. However, there may not be a single recipe for improving SNR at low field, and it is key to embrace the challenges and limitations of each proposed solution. In other words, suitable solutions depend on the final objective or application envisioned for a low-field scanner and, more importantly, on the characteristics of a specific low B 0 $$ {B}_0 $$ field. In this review, we aim to provide an overview on software solutions to improve SNR efficiency at low field. First, we cover techniques for efficient k-space sampling and reconstruction. Then, we present post-acquisition techniques that enhance MR images such as denoising and super-resolution. In addition, we summarize recently introduced electromagnetic interference cancellation approaches showing great promises when operating in shielding-free environments. Finally, we discuss the advantages and limitations of these approaches that could provide directions for future applications.

3.
Sensors (Basel) ; 24(17)2024 Aug 29.
Article in English | MEDLINE | ID: mdl-39275520

ABSTRACT

In the evolving landscape of sixth-generation wireless communication, the integration of visible light communication (VLC) and visible light positioning (VLP), known as visible light positioning and communication (VLPC), emerges as a pivotal technology. This study addresses the challenges of asynchronous code division multiplexing (ACDM) in VLPC networks, focusing on the enhancement of data transmission quality and positioning accuracy. Firstly, we propose an orthogonal pseudo-random code (OPRC) for ACDM-based VLP systems. Leveraging its excellent correlation properties, VLP signals preserve orthogonality even amidst asynchronous transmissions, achieving sub-centimeter average positioning errors. Next, by combining OPRC with successive interference cancellation decoding (SICD), we propose an enhanced ACDM-based VLPC system that utilizes OPRC for improved signal orthogonality and SICD for progressive elimination of multiple access interference (MAI) among VLPC signals. The results show substantial improvements in bit-error rate (BER) and positioning error (PE), approaching the performance levels observed in synchronized VLPC systems. Specifically, the SICD-OPRC scheme reduces average BER to 4.3 × 10-4 and average PE to 2.7 cm, demonstrating its robustness and superiority in complex asynchronous scenarios.

4.
Int J Mol Sci ; 25(17)2024 Aug 28.
Article in English | MEDLINE | ID: mdl-39273287

ABSTRACT

The phenomenon known as bipolar cancellation is observed when biphasic nanosecond electric field pulses are used, which results in reduced electroporation efficiency when compared to unipolar pulses of the same parameters. Basically, the negative phase of the bipolar pulse diminishes the effect of the positive phase. Our study aimed to investigate how bipolar cancellation affects Ca2+ electrochemotherapy and cellular response under varying electric field intensities and pulse durations (3-7 kV/cm, 100, 300, and 500 ns bipolar 1 MHz repetition frequency pulse bursts, n = 100). As a reference, standard microsecond range parametric protocols were used (100 µs × 8 pulses). We have shown that the cancellation effect is extremely strong when the pulses are closely spaced (1 MHz frequency), which results in a lack of cell membrane permeabilization and consequent failure of electrochemotherapy in vitro. To validate the observations, we have performed a pilot in vivo study where we compared the efficacy of monophasic (5 kV/cm × ↑500 ns × 100) and biphasic sequences (5 kV/cm × ↑500 ns + ↓500 ns × 100) delivered at 1 MHz frequency in the context of Ca2+ electrochemotherapy (B16-F10 cell line, C57BL/6 mice, n = 24). Mice treated with bipolar pulses did not exhibit prolonged survival when compared to the untreated control (tumor-bearing mice); therefore, the bipolar cancellation phenomenon was also occurrent in vivo, significantly impairing electrochemotherapy. At the same time, the efficacy of monophasic nanosecond pulses was comparable to 1.4 kV/cm × 100 µs × 8 pulses sequence, resulting in tumor reduction following the treatment and prolonged survival of the animals.


Subject(s)
Electrochemotherapy , Melanoma, Experimental , Animals , Electrochemotherapy/methods , Mice , Cell Line, Tumor , Melanoma, Experimental/drug therapy , Melanoma, Experimental/therapy , Pilot Projects , Electroporation/methods , Mice, Inbred C57BL , Calcium/metabolism
5.
Micromachines (Basel) ; 15(9)2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39337740

ABSTRACT

A novel photonic-assisted multifunctional radar system was proposed and experimentally investigated. This system can simultaneously achieve frequency-doubled linear frequency modulation (LFM) signal generation, de-chirp reception, self-interference cancellation, and frequency measurement in an integrated transmit-receive radar. First, a high-frequency and broadband LO signal was obtained with photonic frequency doubling, which improved the center frequency and bandwidth of the radar detection system. Then, photonic-assisted interference cancellation was used to reduce the impact of interference signals in radar de-chirp reception. Finally, the microwave frequency measurement was achieved by establishing a mapping relationship between the envelope response time of the intermediate frequency (IF) electrical filter and the microwave frequency to be tested. Both theoretical and experimental investigations were performed. The results showed that an LFM signal with a frequency range of 12-18 GHz was obtained with photonic frequency doubling. Photonic-assisted self-interference cancellation reduced the impact of interference signals in radar de-chirp reception by more than 12.1 dB for an LFM signal bandwidth of 6 GHz. In the frequency measurement module, the difference between the frequency to be tested, generated by the external signal source, and that calculated in the experiment is the measurement error, and a measurement resolution better than 14 MHz was achieved in the range of 12.14 GHz-18.14 GHz. The proposed system is suitable for miniaturized multifunctional radar signal processing systems with continuous operation of transmitting and receiving antennas in unmanned aerial vehicles (UAVs), automotive radar, relatively close spatial locations, and so on. In addition, it can simplify the system structure and reduce space occupation.

6.
Sensors (Basel) ; 24(18)2024 Sep 20.
Article in English | MEDLINE | ID: mdl-39338847

ABSTRACT

This paper describes a revolutionary design paradigm for monitoring aquatic life. This unique methodology addresses issues such as limited memory, insufficient bandwidth, and excessive noise levels by combining two approaches to create a comprehensive predictive filtration system, as well as multiple-transfer route analysis. This work focuses on proposing a novel filtration learning approach for underwater sensor nodes. This model was created by merging two adaptive filters, the finite impulse response (FIR) and the adaptive line enhancer (ALE). The FIR integrated filter eliminates unwanted noise from the signal by obtaining a linear response phase and passes the signal without distortion. The goal of the ALE filter is to properly separate the noise signal from the measured signal, resulting in the signal of interest. The cluster head level filters are the adaptive cuckoo filter (ACF) and the Kalman filter. The ACF assesses whether an emitter node is part of a set or not. The Kalman filter improves the estimation of state values for a dynamic underwater sensor networking system. It uses distributed learning long short-term memory (LSTM-CNN) technology to ensure that the anticipated value of the square of the gap between the prediction and the correct state is the smallest possible. Compared to prior methods, our suggested deep filtering-learning model achieved 98.5% of the sensory filtration method in the majority of the obtained data and close to 99.1% of an adaptive prediction method, while also consuming little energy during lengthy monitoring.

7.
Front Med (Lausanne) ; 11: 1406140, 2024.
Article in English | MEDLINE | ID: mdl-39267968

ABSTRACT

Background: Although ophthalmic ambulatory surgeries are less costly and may enhance the more efficient utilization of hospital resources, inpatient surgeries were preferable alternatives for patients with complicated eye diseases or poor general health. However, the incidence, causes, and related factors of ophthalmic inpatient surgery cancellation remained largely unknown. Methods: The electronic medical records of ophthalmic inpatient surgeries between January 2012 and December 2022 was retrospectively reviewed. Cancellation-related factors were explored using multivariate logistic regression analysis and the reasons of cancellation were also evaluated. Results: In total, 820 cancelled surgeries and 42,073 performed surgeries were included, with a cancellation rate of 1.9%. Any other ocular comorbidities were risk factors for cancellation (odds ratio (OR) 1.872, 95% confidence intervals (CI) 1.504-2.331; p < 0.001), while older age (OR 0.990, 95% CI 0.986-0.995; p < 0.001), local residence (OR 0.809, 95% CI 0.692-0.947; p = 0.008), any systemic comorbidities (OR 0.740, 95% CI 0.616-0.889; p = 0.001), and previous history of surgeries (OR 0.403, 95% CI 0.341-0.476; p < 0.001) were negatively associated with surgery cancellation. The top two categorical cancellation reasons were medical factors (508, 62.0%) and patient-related factors (285, 34.8%). "Patient/family refused surgery" (127, 15.5%), "acute conjunctivitis or uveitis relapse" (103, 12.6%), and "ocular condition improved and procedure no longer indicated" (71, 8.7%) were the three most common single cancellation reasons. Conclusion: Any other ocular comorbidities, younger age, no systemic comorbidities, non-local residence, and no past surgical history were related factors for ophthalmic inpatient surgery cancellation. The majority of cancellations were due to patient-related or medical factors. Great importance should be attached to the cancellation of the more complicated inpatient surgeries and further efforts are warranted to explore how to reduce cancellation.

8.
Article in English | MEDLINE | ID: mdl-39237652

ABSTRACT

PURPOSE: The effect of cancellation and postponement of primary total hip arthroplasty (THA) or knee arthroplasty (TKA) on patient outcomes is unclear. The aim was to assess whether cancellation and delay to arthroplasty was associated with worse joint specific function and quality of life (QoL) 1-year postoperatively. METHODS: A single centre retrospective case-control study was performed for all patients planned to undergo THA or TKA in 2019. A total of 3133 arthroplasties were scheduled for 2019 (1484 THA, 1649 TKA), of which 344 (11.0%) were cancelled (136 THA [9.2%], 208 TKA [12.6%]). Pre-operative and one-year post-operative EuroQol (EQ-5D) and Oxford hip (OHS) or knee (OKS) scores were collected. RESULTS: The median time between the date of cancellation and the subsequent operation was 46.0 days for TKA and 45.5 days for THA. The cancelled group were more likely to be male (odds ratio [OR] 1.23, p = 0.03), older (mean difference [MD] 1.19, p = 0.03), with a higher ASA grade (OR 1.88 [ASA 3], OR 5.3 [ASA 4], p = 0.001) or planned for a TKA (OR 1.41, p = 0.003). There were no differences in pre-operative OKS (mean difference [MD] 0.19, p = 0.828) or EQ-5D (MD 0.028, p = 0.394) or in the one-year postoperative OKS (MD 1.51, p = 0.064) or EQ-5D (MD 0.041, p = 0.067) between groups undergoing TKA. However, cancelled THA patients had lower pre-operative OHS (MD 2.73, p = 0.018) and EQ-5D (MD 0.134, p = 0.0017) but at one-year postoperatively there was no difference in the absolute OHS (MD 2.07, p = 0.052) or EQ5D (MD 0.04, p = 0.142). The improvement in hip EQ-5D was greater (MD 0.096, p = 0.016) in the cancelled group. CONCLUSION: Cancellation and short delay did not influence joint specific outcome or QoL following THA or TKA at one-year. Preoperative hip specific pain, function and QoL were worse in cancelled THA patients, suggesting deterioration while waiting for their surgery, but this did not affect their postoperative outcome.

9.
ISA Trans ; 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39284749

ABSTRACT

To address the parameter instability issues in hazardous materials handling during multi-machine loading and unloading operations, we propose a Full-Scale Smart Parameter Optimization Control (FSPOC) system specifically designed for multi-machine coordination. This system leverages a novel fish scale prediction algorithm tailored for cooperative multi-machine environments. Initially, the fish scale prediction algorithm, inspired by bionic fish scales, is developed to predict future system behavior by analyzing historical data. Building on this algorithm, we introduce a disturbance cancellation control theorem and design a parameter optimization controller to enhance stability in high-dimensional nonlinear spaces. The FSPOC method is then applied to a multi-machine cooperative system, enabling online distributed parameter optimization for complex systems with multiple degrees of freedom. The effectiveness of the proposed method was validated through simulations, where it was compared with two other optimization techniques: Genetic Algorithm-based PID (GAPID) and Chaotic Atomic Search Algorithm-based PID (CHASO). The simulation results confirm the superiority of the FSPOC method.

10.
Sensors (Basel) ; 24(15)2024 Aug 03.
Article in English | MEDLINE | ID: mdl-39124085

ABSTRACT

In our paper, we propose a generalized version of the Alternating Projections Digital Hard Successive Interference Cancellation (AP-HSIC) algorithm that is capable of decoding any order of constellation M in an M-Quadrature Amplitude Modulation (QAM) system. Our approach applies to Rayleigh deep-fading Multiple-Input Multiple-Output (MIMO) channels with high-level Additive White Gaussian Noise (AWGN). It can handle various destructive phenomena without restricting the number of antenna arrays in the transmitter/receiver. Importantly, it does not rely on closed-loop MIMO feedback or the need for Channel-State Information Transmission (CSIT). We have demonstrated the effectiveness of our approach and provided a Bit Error Rate (BER) analysis for 16-, 32-, and 64-QAM modulation systems. Real-time simulations showcase the differences and advantages of our proposed algorithm compared to the Multi-Group Space-Time Coding (MGSTC) decoding algorithm and the Lagrange Multipliers Hard Successive Interference Cancellation (LM-HSIC) algorithm, which we have also developed here. Additionally, our paper includes a mathematical analysis of the LM-HSIC algorithm. The AP-HSIC algorithm is not only effective and fast in decoding, including interference cancellation computational feedback, but it can also be integrated with any Linear Processing Complex Orthogonal Design (LPCOD) technique, including Complex Orthogonal Design (COD) schemes such as high-order Orthogonal Space-Time Block Code (OSTBC) with high-order QAM symbols.

11.
J Surg Res ; 302: 329-338, 2024 Aug 09.
Article in English | MEDLINE | ID: mdl-39126874

ABSTRACT

INTRODUCTION: Same-day surgical case cancellation consumes resources, disrupts patient care, and has a global prevalence of 18%. A retrospective analysis found that 44% of scheduled elective surgeries were canceled at a public tertiary hospital in Lilongwe, Malawi. To better characterize these cancellations, this study defines a process map for surgical case completion and investigates hospital staff and patient perspectives on contributing factors and burdens of cancellation. METHODS: We conducted participatory process mapping and in-depth interviews with hospital staff (n = 23) and patients (n = 10) to detail perioperative processes and perspectives on cancellations. We used purposive sampling to recruit staff by hospital role and patients whose surgery had been canceled. Interviews were audio-recorded, translated, and transcribed for process mapping accuracy and thematic analysis using the constant comparative method and NVivo software. RESULTS: Staff delineated specific steps of the perioperative process, generating a process map that identifies inefficiencies and opportunities for intervention. Hospital staff described unavoidable causes of case cancellation, such as unreliable water supply and material shortages. Modifiable causes linked to wasted time and resources were also evident, such as chronic tardiness, communication barriers, and inadequate preoperative assessment. Thematic analysis of perceived impacts of cancellation revealed compromised provider-patient relationships, communication breakdown, and emotional distress. Staff and patients expressed frustration, embarrassment, fear, and demoralization when planned surgeries were canceled. CONCLUSIONS: We demonstrate the use of process mapping as a tool to identify implementation targets for reducing case cancellation rates. Hospital systems can adapt this approach to address surgical case cancellation in their specific setting.

12.
Healthcare (Basel) ; 12(16)2024 Aug 16.
Article in English | MEDLINE | ID: mdl-39201197

ABSTRACT

The psychological impact of medical care accessibility during the pandemic has been widely studied, but little attention has been given to Asian immigrants in Canada. This study aimed to fill this literature gap by using a cross-sectional survey, which aimed to evaluate the impact of the COVID-19 pandemic on Chinese immigrants in North America during the second wave of the pandemic. The study focused on Chinese immigrants aged 16 or older in Canada. Covariates included sociodemographic variables, delayed access to medical care (i.e., treatment or health assessment), and other COVID-19 related variables. We used logistic LASSO regression for model selection and multivariate logistic regression models to evaluate the association between delayed access to treatment/health assessment and psychological distress outcome, as measured by the COVID-19 Peritraumatic Distress Index (CPDI). Missing data were handled using multiple imputation. Our study included 746 respondents, with 47.18% in the normal CPDI group and 36.82% in the mild-to-severe CPDI group. Most respondents were originally from Mainland China and residing in Ontario. Over half have stayed in Canada for at least 15 years. The multivariate logistic regression models identified significant risk predictors of psychological distress status: delayed access to medical care (OR = 1.362, 95% CI: 1.078-1.720, p = 0.0095), fear of COVID-19 (OR = 1.604, 95% CI: 1.293-1.989, p < 0.0001), and social loneliness (OR = 1.408, 95%CI: 1.314-1.508, p < 0.0001). Sociodemographic variables and other COVID-19-related variates did not significantly impact the study's outcome. Our findings shed light on the importance of timely medical care access to psychological well-being among Chinese Canadians. Reliable health information, mental health support, and virtual care tailored to immigrants should be considered to mitigate this impact and promote their overall health and well-being.

13.
Int J Mol Sci ; 25(16)2024 Aug 12.
Article in English | MEDLINE | ID: mdl-39201461

ABSTRACT

Electroporation-based procedures employing nanosecond bipolar pulses are commonly linked to an undesirable phenomenon known as the cancelation effect. The cancellation effect arises when the second pulse partially or completely neutralizes the effects of the first pulse, simultaneously diminishing cells' plasma membrane permeabilization and the overall efficiency of the procedure. Introducing a temporal gap between the positive and negative phases of the bipolar pulses during electroporation procedures may help to overcome the cancellation phenomenon; however, the exact thresholds are not yet known. Therefore, in this work, we have tested the influence of different interphase delay values (from 0 ms to 95 ms) using symmetric bipolar nanoseconds (300 and 500 ns) on cell permeabilization using 10 Hz, 100 Hz, and 1 kHz protocols. As a model mouse hepatoma, the MH-22a cell line was employed. Additionally, we conducted in vitro electrochemotherapy with cisplatin, employing reduced interphase delay values (0 ms and 0.1 ms) at 10 Hz. Cell plasma membrane permeabilization and viability dependence on a variety of bipolar pulsed electric field protocols were characterized. It was shown that it is possible to minimize bipolar cancellation, enabling treatment efficiency comparable to monophasic pulses with identical parameters. At the same time, it was highlighted that bipolar cancellation has a significant influence on permeabilization, while the effects on the outcome of electrochemotherapy are minimal.


Subject(s)
Cell Membrane Permeability , Electrochemotherapy , Electrochemotherapy/methods , Animals , Mice , Cell Membrane Permeability/drug effects , Cell Line, Tumor , Electroporation/methods , Cisplatin/pharmacology , Cell Membrane/metabolism , Cell Membrane/drug effects , Cell Survival/drug effects , Carcinoma, Hepatocellular/drug therapy , Antineoplastic Agents/pharmacology
14.
Sensors (Basel) ; 24(14)2024 Jul 13.
Article in English | MEDLINE | ID: mdl-39065934

ABSTRACT

Recently, reconfigurable intelligent surfaces (RISs) have attracted increasing attentions in the design of full-duplex (FD) systems due to their novel capability of propagation environment reconfiguration. However, in conventional RIS-assisted FD systems, the beamforming for self-interference cancellation (SIC) and sum rate maximization (SRM) are highly coupled during RIS optimization, which significantly degrades the system performance. To tackle this issue, we exploit a novel bilayer intelligent omni-surface (BIOS) structure in FD systems. Compared with the conventional RIS designs, the BIOS provides independent beams on both sides, thus enabling more flexible achievement of SRM and SIC. For the BIOS-assisted FD system, we first formulate an optimization problem to achieve SRM and efficient SIC simultaneously. Then, we exploit the relationship between the SRM and mean square error (MSE), and propose a weighted MSE minimization with SIC algorithm to solve the problem. Specifically, we jointly design the beamforming at the base station and the BIOS with manifold optimization while guaranteeing an SIC constraint. Furthermore, we theoretically derive a lower band for the BIOS size required for efficient SIC in FD systems. Simulation results indicate that the BIOS outperforms the conventional RIS designs in FD systems, and verify the accuracy of the derived lower bound for the BIOS size.

15.
Neuroimage ; 297: 120717, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38971482

ABSTRACT

Self-initiated sensory action effects are widely assumed to lead to less intense perception and reduced neural responses compared to externally triggered stimuli (sensory attenuation). However, it is unclear if sensory attenuation occurs in all cases of action-effect prediction. Specifically, when predicted action-effects are relevant to determine follow-up actions attenuation could be detrimental. We quantified auditory event-related potentials (ERP) in electroencephalography (EEG) when human participants created two-sound sequences by pressing two keys on a keyboard associated with different pitch, giving rise to identity-specific action-effect prediction after the first keypress. The first sound corresponded to (congruent) or violated (incongruent) the predicted pitch and was either relevant for the selection of the second keypress to correctly complete the sequence (Relevance) or irrelevant (Control Movement), or there was only one keypress and sound (Baseline). We found a diminished P2-timed ERP component in incongruent compared to congruent trials when the sound was relevant for the subsequent action. This effect of action-effect prediction was due to an ERP reduction for incongruent relevant sounds compared to incongruent irrelevant sounds at P2 latencies and correlated negatively with modulations of pupil dilation. Contrary to our expectation, we did not observe an N1 modulation by congruency in any condition. Attenuation of the N1 component seems absent for predicted identity-specific auditory action effects, while P2-timed ERPs as well as pupil size are sensitive to predictability, at least when action effects are relevant for the selection of the next action. Incongruent relevant stimuli thereby take a special place and seem to be subject to attentional modulations and error processing.


Subject(s)
Electroencephalography , Evoked Potentials, Auditory , Pupil , Humans , Male , Female , Evoked Potentials, Auditory/physiology , Young Adult , Adult , Pupil/physiology , Auditory Perception/physiology , Acoustic Stimulation , Psychomotor Performance/physiology , Reaction Time/physiology
16.
Sensors (Basel) ; 24(11)2024 May 24.
Article in English | MEDLINE | ID: mdl-38894178

ABSTRACT

With the increasing demand for data exchange between nearby devices in proximity-based services, enhancing the security of wireless mutual broadcast (WMB) networks is crucial. However, WMB networks are inherently vulnerable to eavesdropping due to the open broadcast nature of their communication. This paper investigates the improvement of secrecy performance in random-access-based WMB (RA-WMB) networks by integrating physical layer security (PLS) techniques with hybrid duplex (HBD) operations under a stochastic geometry framework. The HBD method balances half-duplex (HD) receiving and full-duplex (FD) transceiving, utilizing self-interference cancellation (SIC) to enhance PLS performance. Key operational parameters, including transmission probability (TxPr), friendly jammer density, and conditions for FD operation, are designed to maximize secrecy performance. The analytical and numerical results demonstrate significant improvements in PLS performance, with SIC playing a critical role, particularly in scenarios with dense legitimate nodes, and with TxPr adjusted to balance HD receiving and FD transceiving based on SIC imperfections. The proposed design principles provide a comprehensive framework for enhancing the security of WMB networks, addressing the complex interplay of interference and SIC in various network configurations.

17.
Cureus ; 16(5): e59845, 2024 May.
Article in English | MEDLINE | ID: mdl-38854335

ABSTRACT

Introduction Various types of fonts such as serif, sans serif, and script are used during writing and reading, which can affect the reader's attention and working memory, though there is only a subtle difference at the end of the letter. The study aimed to see the effect of font type on working memory and attention. Methods The study included healthy male adults between 18 and 40 years of age. After taking all the necessary precautions, a letter cancellation test and 2-back task in serif, sans serif, and script font types were done to evaluate subjects' attention and working memory. Results A total of 30 subjects participated in the study. The letter cancellation task (LCT) was statistically significant (P<0.05) between the three groups, where the time taken to complete the task was the shortest for serif fonts, indicating heightened attention to serif fonts. However, the accuracy of the N-back test did not show statistically significant differences (P>0.05) among the three font groups, indicating no significant change in working memory. Conclusion The type of font used can impact the reader's attention, with Times New Roman font demonstrating greater attention, particularly in the context of the letter cancellation task.

18.
Cureus ; 16(5): e60159, 2024 May.
Article in English | MEDLINE | ID: mdl-38868276

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic resulted in unprecedented restrictions on the general public and disturbances to the routines of hospitals worldwide. These restrictions are now being relaxed as the number of vaccinated individuals increases and as the rates of incidence and prevalence decrease; however, they left a lasting impact on healthcare systems that is still being felt today. This retrospective study evaluated the total number of canceled or missed outpatient clinic appointments in a Neurological Surgery department before and after peak COVID-19 restrictions and attempted to assess the impact of these disruptions on neurosurgical clinical attendance. We also attempted to compare our data with the data from another surgical subspecialty department. We evaluated 32,558 scheduled appointments at the Loyola University Medical Center Department of Neurological Surgery, as well as 139,435 scheduled appointments with the Department of Otolaryngology. Appointments before April 2020 were defined as pre-COVID, while appointments during or after April 2020 were defined as post-COVID. Here, we compare no-show and non-attendance rates (no-shows plus late-canceled appointments) within the respective time range. Overall, we observed that before COVID-19 restrictions were put into place, there was an 8.9% no-show rate and a 17.4% non-attendance rate for the Department of Neurological Surgery. After COVID restrictions were implemented, these increased to 10.9% and 18.3%, respectively. Greater no-show and cancellation rates (9.8% in the post-COVID era vs 8.0% in the pre-COVID era) were associated with varying socioeconomic and racial demographics. African-American patients (2.56 times higher), new-visit patients (1.67 times higher), and those with Medicaid/Medicare insurance policies (1.48 times higher) were at the highest risk of no-show in the post-COVID era compared to the pre-COVID era.

19.
Front Sociol ; 9: 1336160, 2024.
Article in English | MEDLINE | ID: mdl-38698934

ABSTRACT

Australia has been widely condemned for its harsh and comprehensive external border controls that seek to control the inward mobility of would-be asylum seekers through visa denial, interdiction and offshore detention. Less widely discussed is the fact that internal controls have been repeatedly ramped up over the past two decades. This includes the administrative removal of lawfully-present non-citizens following visa cancellation on character grounds under s501 of the Migration Act 1958 (Cth). Automatic visa cancellation was introduced in 2014 for non-citizens sentenced to a prison term of 12 months or more, or for certain offences, bypassing individualised decision-making and raising the spectre of a visa cancellation pipeline feeding a highly automated deportation machinery. In an age of increasingly automated forms of governance, a key question that arises is the role that has been played by automated systems in achieving what has been a seismic shift in practice, and the normative implications of any developments towards automation within the visa cancellation and removal systems. This paper outlines the shift towards automation in other systems of governance in Australia-most notably the notorious Robodebt scheme-before examining automation in Australia's visa cancellation system. Documentary analysis of recent parliamentary inquiries, independent reports and government policy is used to piece together the development of inter-agency data exchange practices and automation over three specific periods-historical practice pre-2014, post-2014 to the present, and proposed future developments. We conclude that Australia's s501 visa cancellation system is neither automated nor automatic. Rather, the 2014 law reform gave rise to a 'surveillance fantasy' with immense consequences for non-citizens, particularly those who face long days in immigration detention at the conclusion of their prison sentence. We show that while concerns about increasing automation are well-founded, systems based on less sophisticated forms of information handling and reliant on human decision-making nevertheless continue to raise age-old questions concerning efficiency, accuracy and fairness.

20.
Micromachines (Basel) ; 15(5)2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38793166

ABSTRACT

Combined in-band full duplex-multiple input multiple output (IBFD-MIMO) technology can significantly improve spectrum efficiency and data throughput, and has broad application prospects in communications, radar, the Internet of Things (IoT), and other fields. Targeting the self-interference (SI) issue in microwave photonic-based IBFD-MIMO communication systems, a microwave photonic self-interference cancellation (SIC) method applied to the narrowband 2 × 2 IBFD-MIMO communication system was proposed, simulated, and analyzed. An interleaver was used to construct a polarization multiplexing dual optical frequency comb with a frequency shifting effect, generating a dual-channel reference interference signal. The programmable spectrum processor was employed for filtering, attenuation, and phase-shifting operations, ensuring amplitude and phase matching to eliminate the two self-interference (SI) signals. The simulation results show that the single-frequency SIC depth exceeds 45.8 dB, and the narrowband SIC depth under 30 MHz bandwidth exceeds 32.7 dB. After SIC, the desired signal, employing a 4QAM modulation format, can be demodulated with an error vector magnitude (EVM) as low as 4.7%. Additionally, further channel expansion and system performance optimization are prospected.

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