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Toward Reliability of Long Wireless Sensor Networks
No full textWireless sensor networks have become pervasive in various applications, including environ mental monitoring, smart cities, precision agriculture, and healthcare. In particular, linear wireless sensor networks that span considerable distances are increasingly deployed for applications such as pipeline monitoring and transportation systems. However, ensuring the reliability of long wireless sensor networks poses significant challenges due to the unique characteristics of the network topology and the constraints imposed by the resource-constrained sensor nodes. There is a notable lack of methods for the analysis and optimization of the reliability of large-scale sensor networks, and in this paper, we partially fill this gap. We propose a method for assessing the tradeoff between redundancy of forward error correction and reliable packet delivery. We also consider approaches to improve the reliability of linear sensor networks based on increasing topology connectivity and provide a corresponding method for the exact calculation of the all-terminal reliability. Numerical experiments demonstrate the relevance and effectiveness of our results. This research contributes to a deeper understanding of the underlying principles governing the reliability of long wireless sensor networks and provides valuable insights for the design, optimization, and management of such networks in real-world applications
Comparison of Short-Term Clinical Outcomes After Implantation of Two Monofocal, Aspheric Intraocular Lenses
No full textObjectives: This study compared the visual outcomes and optical quality of two monofocal, aspheric intraocular lenses (IOLs; CT LUCIA 621P, Carl Zeiss Meditec; Eyhance ICB00, Johnson & Johnson Vision) by evaluating visual acuity, contrast sensitivity, and higher-order aberrations 1 month post-cataract surgery. Methods: In this retrospective, comparative study, 120 eyes (72 patients) that underwent cataract surgery with either CT LUCIA 621P (Lucia group) or Eyhance ICB00 (Eyhance group) implantation (60 eyes/group) were retrospectively investigated. Visual acuity at various distances and defocus curves were measured 1 month postoperatively. Optical quality was assessed by comparing contrast sensitivity and internal coma, spherical, and total aberrations by using iTrace (Tracey Technology), a ray-tracing-type aberrometer. Results: The visual acuity and defocus curves were similar between the two IOLs 1 month postoperatively. The Lucia group showed better contrast sensitivity at higher spatial frequencies: 12 cpd (p < 0.001, 1.32 LogCS vs. 1.02 LogCS) and 18 cpd (p = 0.009, 0.74 LogCS vs. 0.47 LogCS) unilaterally and 18 cpd (p = 0.044, 0.94 LogCS vs. 0.60 LogCS) bilaterally. Postoperative internal spherical aberration was significantly lower in the Lucia group (p < 0.001, -0.04 µm vs. -0.003 µm). Internal coma and total aberrations were similar. Conclusions: The visual acuity and defocus curves of the Lucia and Eyhance groups were comparable 1 month post-cataract surgery. The Lucia group’s superior contrast sensitivity and lower postoperative internal spherical aberration were due to differences in IOL designs, particularly the power variation patterns
Superficial Inferior Epigastric Artery Flap: Vascular Pattern and Territory Across the Midline
No full textBackground: Superficial inferior epigastric artery (SIEA) flap offers a significant advantage of lower donor site morbidity over other abdominal-based flaps for breast reconstruction. However, the inconsistent anatomy and territory across the midline remains a major issue. This study aimed to investigate the SIEA and determine its pattern and territory across the midline.
Methods: Twenty cadavers were studied. Ipsilateral dye was injected to the dominant SIEA. Dissection was performed to evaluate the SIEA origin, artery and vein pattern, vessel diameter, and dye diffusion territory.
Results: Overall, three SIEA patterns were identified: bilateral presence (45%), ipsilateral presence (30%), and bilateral absence (25%). The territory depended on the vessel course and dominant SIEA diameter, not on its common origin from the femoral artery, at the pubic tubercle level. Regarding the midline territory (pubic tubercle level to umbilicus), SIEA (type 1a) with a diameter of ≥1.4 mm on either side supplied at least half the distance, whereas SIEA with a diameter of <1 mm was limited to the suprapubic area.
Conclusion: Designing a SIEA flap island across the midline is feasible when contralateral SIEA is present to augment the contralateral territory (e.g., type 1a SIEA) or in SIEA with a common/superficial external pudendal artery origin. Preoperative imaging studies are important for confirming the SIEA system. When the diameter at the origin of the SIEA flap is larger than 1.4 mm, the blood supply to the ipsilateral and contralateral sides is sufficient to enable safe flap elevation
Effect of Severe Fever With Thrombocytopenia Syndrome Virus Genotype on Disease Severity, Viral Load, and Cytokines in South Korea
No full textBackground: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne disease caused by Bandavirus dabieense (SFTS virus [SFTSV]). Recently, at least 6 different genotypes of SFTSV have been identified, with genotypes A, D, and F dominant in China and B dominant in Japan and Korea. This study investigated the effect of SFTSV genotypes circulating in South Korea on disease severity, viral load, and cytokine profile.
Methods: We prospectively enrolled 70 patients with SFTS from July 2015 to June 2022. Serial plasma samples were obtained during hospitalization and analyzed. Viral load was measured by real-time reverse-transcription polymerase chain reaction. Partial sequences of the viral genome were analyzed for genotyping. Plasma concentrations of 17 cytokines were measured by multiplex-bead immunoassay.
Results: Of 70 samples, 51 could be genotyped. Genotype B was predominant (80.4%) and other genotypes were uncommon. Intensive care unit admission rates (51.2% vs 50.0%) and mortality rates (26.8% vs 40.0%) did not show any significant differences between genotype B and non-B genotypes. The initial viral load did not show any significant differences (3.59 vs 3.64 log copies/μL), whereas viral load measured at hospital day 3-4 tended to be higher in genotype B than non-B genotypes (3.83 vs 1.83 log copies/μL, P = .07). Additionally, the plasma concentrations of interferon-α, interleukin 10, and interferon-γ-induced protein 10, which are closely related to mortality in cases of SFTS, did not show any significant differences.
Conclusions: SFTSV genotype B was the prevalent genotype in South Korea, with no genotype-specific difference in clinical outcomes, initial viral load, or cytokine profiles
Development of a Hardware-in-the-Loop Platform for a Teleoperation Flexibility Robotic System
No full textA control method for a cable-driven robot in a teleoperation system is proposed using the hardware-in-the-loop (HIL) simulation technique. The main components of the teleoperated robotic system are a haptic device, also called a delta robot, and a cable-driven hyper-redundant (CDHR) robot. The CDHR manipulator has higher flexibility and multiple degrees of freedom (DOF), and, therefore, its inverse kinematics are complex. For this reason, the Jacobian method is used in place of the conventional method to calculate the inverse kinematics. Moreover, the two robots constituting the telerobotic system are different in terms of their mechanical structures and workspaces. Therefore, the position mapping method is applied to ensure that the two workspaces are utilized together. However, a singularity area appears when the mapping parameter is adjusted to expand the workspace. Therefore, a haptic algorithm is proposed to prevent the robot from moving into the singularity region and generate force feedback at the end-effector of the haptic device to warn the operator. Because experimental verification of this control strategy is difficult, the HIL technique is used for demonstration in this study to ensure stability and safety before implementation of the method at the experiment scale. The CDHR robot is designed using SolidWorks 2021. Then, the Simscape model is used to simulate the telerobotic system. In addition, the protocol between the haptic device and the laptop is programmed using C/C++ language to facilitate communication with the CDHR robot in MATLAB Simulink 2022a. A few trials are conducted to evaluate and demonstrate the effectiveness of the proposed method
Comparison of Clinical Outcomes After Different Surgical Approaches for Lateral Epicondylitis: A Systematic Review and Meta-analysis
No full textBackground: Lateral epicondylitis (LE) is one of the most common causes of lateral elbow pain. When nonoperative treatment fails, 1 of the 3 surgical approaches-open, percutaneous, or arthroscopic-is used. However, determining which approach has the superior clinical outcome remains controversial.
Purpose: To review the outcomes of different operative modalities for LE qualitatively and quantitatively.
Study design: Systematic review; Level of evidence, 4.
Methods: This review was performed and reported according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies published in PubMed, Medline (via EBSCO), and ScienceDirect databases that treated LE with open, percutaneous, or arthroscopic approaches with at least 12 months of follow-up were included. Study quality was assessed using the Cochrane Risk of Bias 2 tool and the Methodological Index for Non-Randomized Studies score. The primary outcome was the success rate of each operative treatment approach-open, percutaneous, and arthroscopic.
Results: From an initial search result of 603 studies, 43 studies (n = 1941 elbows) were ultimately included. The arthroscopic approach had the highest success rate (91.9% [95% CI, 89.2%-94.7%]) compared with the percutaneous (91% [95% CI, 87.3%-94.6%]) and open (82.7% [95% CI, 75.6%-89.8%]) approaches for LE surgery with changes in the mean visual analog scale pain score of 5.54, 4.90, and 3.63, respectively. According to the Disabilities of the Arm, Shoulder and Hand score, the functional outcome improved in the arthroscopic group (from 54.11 to 15.47), the percutaneous group (from 44.90 to 10.47), and the open group (from 53.55 to 16.13). The overall improvement was also found in the Mayo Elbow Performance Score, the arthroscopic group (from 55.12 to 90.97), the percutaneous group (from 56.31 to 87.65), and the open group (from 64 to 93.37).
Conclusion: Arthroscopic surgery had the highest rate of success and the best improvement in functional outcomes among the 3 approaches of LE surgery
Investigating the molecular mechanisms of ADAR1 in colon cancer
No full textADAR1 (adenosine deaminase acting on RNA) binds to double-stranded RNA (dsRNA) and catalyzes the deamination of adenosine through RNA editing to generate inosine. ADAR1 is known to inhibit the IFN (type I interferon) response and restrict the interaction between ZBP1 and RIPK3, thus suppressing ZBP1-mediated necroptosis. However, its mechanism in colon cancer is not clearly understood. This study analyzed changes in IFN signaling and ZBP1-mediated necroptosis pathway in ADAR1-depleted colon cancer cells with inducible knockdown using the tet on shADAR1 system, to clarify how ADAR1 regulates IFN signaling and ZBP1-mediated necroptosis. However, in contrast to previous studies, these observations showed that ADAR1 knockdown in colon cancer cells did not lead to activation of IFN signaling and ZBP1-mediated necroptosis. Furthermore, it was noted that the activation of IFN signaling, and ZBP1-mediated necroptosis did not occur upon ADAR1 knockdown, even in the presence of IFN and CBL0137 treatment. Therefore, our results suggest that ADAR1 exists in colon cancer cells in a different pathway than the known type I IFN signaling pathway and ZBP1-mediated necroptosis through RNA editing.Maste
Comparison of preoxygenation with a high-flow nasal cannula and a simple face mask before intubation in Korean patients with head and neck cancer
No full textBackground: Although preoxygenation is an essential procedure for safe endotracheal intubation, in some cases securing sufficient time for tracheal intubation may not be possible. Patients with head and neck cancer might have a difficult airway and need a longer time for endotracheal intubation. We hypothesized that the extended apneic period with preoxygenation via a high-flow nasal cannula (HFNC) is beneficial to patients who undergo head and neck surgery compared with preoxygenation with a simple mask.
Methods: The study was conducted as a single-center, single-blinded, prospective, randomized controlled trial. Patients were divided into groups based on one of the two preoxygenation.
Methods: HFNC group or simple facemask (mask group). Preoxygenation was performed for 5 minutes with each method, and endotracheal intubation for all patients was performed using a video laryngoscope. Oxygen partial pressures of the arterial blood were compared at the predefined time points.
Results: For the primary outcome, the mean arterial oxygen partial pressure (PaO2 ) immediately after intubation was 454.2 mm Hg (95% confidence interval [CI], 416.9-491.5 mm Hg) in the HFNC group and 370.7 mm Hg (95% CI, 333.7-407.4 mm Hg) in the mask group (P=0.002). The peak PaO2 at 5 minutes after preoxygenation was not statistically different between the groups (P=0.355).
Conclusions: Preoxygenation with a HFNC extending to the apneic period before endotracheal intubation may be beneficial in patients with head and neck cancer
The impact of maxillary dimensions on determining surgical approach of fungal ball in the maxillary sinus
No full textEndoscopic middle meatal antrostomy (MMA) is commonly used for maxillary sinus (MS) fungal ball removal. For challenging cases involving anterior or inferior recess, an additional inferior meatal approach (IMA) might be needed. We analyzed the differences in MS dimensions on CT scans according to the surgical approach to suggest preoperative variables that could facilitate an additional IMA. CT scans of 281 adult patients who underwent ESS for the MS fungal ball (139 MMA, 62 MMA & IMA) were evaluated for comparative analysis of 8 MS measurements based on the surgical approach. Complete removal was achieved in all cases. Age and sex didn't differ significantly (p > 0.05). The maximum distances between the anterior-posterior walls, the inferior ostium border to the lateral recess, and the ostium to the inferior wall of the MS were statistically greater in the MMA & IMA group compared to the MMA group (p = 0.003, p = 0.005, and p = 0.010, respectively), especially among females. This study underscores the clinical importance of specific measurements-anterior to posterior wall, medial wall to lateral recess, and ostium to inferior wall of the maxillary sinus-for guiding optimal surgical approaches in MS lesions
Development of a predictive scoring system for the long term joint survivorship following arthroscopic partial medial meniscectomy
No full textBackground: The approach to treating degenerative medial meniscal tears (DMTs) has transitioned from a strategy that prioritized meniscectomy to one that emphasizes meniscus preservation whenever possible. However, not all patients respond to conservative treatment, and the symptom-relieving effect of arthroscopic partial medial meniscectomy (APM) is widely accepted in orthopaedic practice. Establishing appropriate surgical indications requires a prognostic prediction model incorporating numerous clinicoradiologic factors that interact with each other. Purpose/Hypothesis: This study aimed to develop a predictive scoring system for the long- term joint survivorship following APM using a machine learning technique. It was hypothesized that selected preoperative factors could predict lower survival rates following APM when treating DMTs. Study Design: Cohort study; Level of evidence, 3. Methods: Patients who underwent APM for DMTs during 1999–2010 were retrospectively reviewed. The following inclusion criteria were applied: (1) diagnosis of DMTs on preoperative magnetic resonance imaging (MRI) scans, (2) no definite history of trauma, (3) follow-up duration >5 years. Joint survival rates were assessed with the endpoint being defined as conversion to arthroplasty (or realignment osteotomy) or progression to Kellgren-Lawrence grade 4. Investigated predictive factors included demographics, anatomic tibiofemoral angle (aTFA), posterior tibial slope (PTS), cartilage status of the medial and lateral compartments, medial meniscus tear pattern, preoperative subchondral bone marrow lesion (BML), and subchondral insufficiency fracture of the knee (SIFK) lesion. A scoring system was developed to stratify the survival rate following APM. Least absolute shrinkage and selection operator (LASSO)-based Cox regression was used to select the predictive factors of the scoring system, and assigned scores were determined based on the hazard ratio of each factor. Calibration plot was generated to compare the model-based predicted survival rates with the observed survival rates. Results: A total of 633 knees were included, with a mean follow-up duration of 114.6 ± 47.4 months (range, 60–245 months). During that period, 151 cases experienced failure. The 10- year joint survival rate was 82.3% (95% confidence intervals [CI] 79.0–85.6%). After selection by LASSO-based Cox regression, the following factors (assigned scores) were incorporated into a scoring system: age ≥60 years (2 points), aTFA <2° (2 points), cartilage status of the medial compartment (2 points for grade 2 and 5 points for grade 3), cartilage status of the lateral compartment (1 point for grade 2 and 3 points for grade 3), preoperative subchondral BML (1 point for grade 1, 2 points for grade 2, and 3 points for grade 3), and SIFK lesion (2 points). The joint survivorship was assessed by dividing the total scores into five groups, and for scores of ≥9 points, the 10-year joint survival rate was 51.5% (95% CI, 40.7–61.2%). When comparing the predicted survival rates and observed survival rates in each of the five groups, the calibration plots generally demonstrated a linear pattern. Clinical outcomes were evaluated using the Lysholm scores. Conclusion: The long-term joint survivorship following APM can be reliably predicted using the developed scoring system. The top scoring factor was grade 3 medial compartment cartilage status followed by grade 3 subchondral BML and grade 3 lateral compartment cartilage status. A total score of 9 points or higher resulted in a nearly 50% reduction in the 10-year joint survival rate. This scoring system provides a basis for an individual risk calculator to assess prognosis and determine indications for APM when treating DMTs. Key terms: medial meniscus; degenerative tear; meniscectomy; machine learningDocto