614 research outputs found

    Optimization of the overall success probability of the energy harvesting cognitive wireless sensor networks

    Get PDF
    Wireless energy harvesting can improve the performance of cognitive wireless sensor networks (WSNs). This paper considers radio frequency (RF) energy harvesting from transmissions in the primary spectrum for cognitive WSNs. The overall success probability of the energy harvesting cognitive WSN depends on the transmission success probability and energy success probability. Using the tools from stochastic geometry, we show that the overall success probability can be optimized with respect to: 1) transmit power of the sensors; 2) transmit power of the primary transmitters; and 3) spatial density of the primary transmitters. In this context, an optimization algorithm is proposed to maximize the overall success probability of the WSNs. Simulation results show that the overall success probability and the throughput of the WSN can be significantly improved by optimizing the aforementioned three parameters. As RF energy harvesting can also be performed indoors, hence, our solution can be directly applied to the cognitive WSNs that are installed in smart buildings

    Energy harvesting non-orthogonal multiple access system with multi-antenna relay and base station

    Get PDF
    In this paper, we consider downlink non-orthogonal multiple access cooperative communication system. The base station (BS) serves two types of users, which are named relay user (RU) and far user (FU). The BS and RU are equipped with multiple transmit antennas. The RU harvests energy from the BS transmissions to perform the relaying operation for the FU. We have considered 1) amplify-forward; 2) decode-forward; and 3) quantize-map-forward relaying protocols at the RU. As the BS and RU have multiple antennas, therefore we consider 1) beamforming and 2) random antenna selection strategies at the BS and RU. Closed form expressions for the outage probability are provided for the aforementioned relay protocols and antenna strategies. Further, we show that for certain data rate range of the relay and FU the quantize-map-forward relaying protocol can perform better than the other two relaying protocols

    A Factor Analysis of Urban Railway Casualty Accidents and Establishment of Preventive Response Systems

    Get PDF
    AbstractSince the commencement of urban railways in 1974 and KTX service in 2014, the use of railways has been steadily increasing. The number of people using rail transportation has been steadily rising. As a result, this has also led to an increase in the number of passenger-related accidents that are occurring within railway stations. In an effort to prevent such accidents, much of the rail operation system is now automated. Nevertheless, the potential risks of railway accidents are very much present today. This study has utilized the railway accident databases of rail operators to allow for analysis of different types of railway accidents, age of accident victims, gender of accident victims, pedestrian facilities involved in accidents, passengers involved in accidents, and underlying causes of rail accidents. Based on these statistics and analyses, this paper proposes the development of a railway safety education program and the establishment of railway safety education centers as a means of preventing railway accidents

    Efficacy and Safety of Autologous Stromal Vascular Fraction in the Treatment of Empty Nose Syndrome

    Get PDF
    Objectives Regenerative treatment using stem cells may serve as treatment option for empty nose syndrome (ENS), which is caused by the lack of turbinate tissue and deranged nervous system in the nasal cavity. We aimed to assess the efficacy and safety of the autologous stromal vascular fraction (SVF) in the treatment of ENS. Methods In this prospective observational clinical study, we enrolled 10 ENS patients who volunteered to undergo treatment of ENS through the injection of autologous SVF. Data, including demographic data, pre- and postoperative Sino-Nasal Outcome Test-25 (SNOT-25) scores, overall patient satisfaction, and postoperative complications, were prospectively collected. Nasal secretion was assessed using the polyurethane foam absorption method, and the levels of biological markers were analyzed in both ENS group and control group using enzyme-linked immunosorbent assay. The SVF extracted from abdominal fat was diluted and injected into both inferior turbinates. Results Among the 10 initial patients, one was excluded from the study. Subjective satisfaction was rated as ā€œmuch improvedā€ in two and ā€œno changeā€ in seven. Among the improved patients, the mean preinjection SNOT-25 score was 55.0 and the score at 6 months after injection was 19.5. However, the average SNOT-25 score of nine participants at 6 months after injection (meanĀ±standard deviation, 62.4Ā±35.8) did not differ significantly from the baseline SNOT25 score (70.1Ā±24.7, P>0.05, respectively). Among the various inflammatory markers assessed, the levels of interleukin (IL)-1Ī², IL-8, and calcitonin gene-related peptide were significantly higher in ENS patients. Compared with preinjection secretion level, the nasal secretions from SVF-treated patients showed decreased expressions of IL-1Ī² and IL-8 after injection. Conclusion Although SVF treatment appears to decrease the inflammatory cytokine levels in the nasal mucosa, a single SVF injection was not effective in terms of symptom improvement and patient satisfaction. Further trials are needed to identify a more practical and useful regenerative treatment modality for patients with ENS

    Discrepancies in Perception of Urinary Incontinence between Patient and Physician after Robotic Radical Prostatectomy

    Get PDF
    PURPOSE: Reported incidence of urinary incontinence after a radical prostatectomy (RP) varies between studies. This may be due not only to the definition of incontinence applied, but also how the information is acquired. We investigated the differences in perception of post robot-assisted laparoscopic RP (RALP) urinary incontinence acquired through doctor interviews and patient-reported questionnaires. MATERIALS AND METHODS: Of 238 consecutive men who underwent RALP by a single surgeon between July 2005 and February 2008, we evaluated 66 men using the International Consultation on Incontinence Questionnaire (ICIQ) at various time points after surgery. Each patient's ICIQ results were considered to be the patient's perceptions of urinary incontinence. The physician at the same time directly interviewed the patients about the number of pads used and considered complete continence to be equivalent to the use of no pads or safety liners. RESULTS: Of the 66 patients, the physician reported that 34 (51.5%) had obtained complete continence. However, analysis of the questionnaires of these 34 patients revealed that only 5 (14.7%) patients reported that they never leaked during the past 4 weeks. Most patients (11 patients, 32.4%) who did not use any pad did in fact reported leakage of a small or moderate amount of urine about once a day. CONCLUSION: Our results indicate that there are discrepancies in the perception of urinary incontinence between doctor and patient after RALP. Nonuse of pads is not equivalent to obtaining complete urinary continence. Therefore, the number of pads used is not a good measure to determine the status of complete urinary continence.ope

    High Dose Vitamin D3 Attenuates the Hypocalciuric Effect of Thiazide in Hypercalciuric Rats

    Get PDF
    Thiazide is known to decrease urinary calcium excretion. We hypothesized that thiazide shows different hypocalciuric effects depending on the stimuli causing hypercalciuria. The hypocalciuric effect of hydrochlorothiazide (HCTZ) and the expression of transient receptor potential vanilloid 5 (TRPV5), calbindin-D28K, and several sodium transporters were assessed in hypercalciuric rats induced by high calcium diet and vitamin D3. Urine calcium excretion and the expression of transporters were measured from 4 groups of Sprague-Dawley rats; control, HCTZ, high calcium-vitamin D, and high calcium-vitamin D with HCTZ groups. HCTZ decreased urinary calcium excretion by 51.4% in the HCTZ group and only 15% in the high calcium-vitamin D with HCTZ group. TRPV5 protein abundance was not changed by HCTZ in the high calcium-vitamin D with HCTZ group compared to the high calcium-vitamin D group. Protein abundance of NHE3, SGLT1, and NKCC2 decreased in the hypercalciuric rats, and only SGLT1 protein abundance was increased by HCTZ in the hypercalciuric rats. The hypocalciuric effect of HCTZ is attenuated in high calcium and vitamin D-induced hypercalciuric rats. This attenuation seems to have resulted from the lack of HCTZ's effect on protein abundance of TRPV5 in severe hypercalciuric condition induced by high calcium and vitamin D

    A Case of Urine Leakage: An Unusual Complication after Renal Biopsy

    Get PDF
    Renal biopsy is a crucial method in the diagnosis and treatment of acute renal failure of unknown origin, nephrotic syndrome, suspicious interstitial nephritis, and glomerulonephritis as a possible cause of hematuria or proteinuria. Complications occur in 2% to 8% of patients after percutaneous renal biopsy. Complications include gross hematuria, perirenal hematoma, arteriovenous fistula, aneurysm, injury of other organs, and urine leakage. Urine leakage as a complication after kidney biopsy is rare. We experienced a case of urine leakage into the intra-abdominal cavity after renal biopsy

    Role of age and sex in determining antibiotic resistance in febrile urinary tract infections

    Get PDF
    SummaryObjectivesTo identify the age- and sex-specific antimicrobial susceptibility patterns of Gram-negative bacteria (GNB) in outpatient febrile urinary tract infections (UTIs) in Korea.MethodsA total 2262 consecutive samples collected from patients aged 1ā€“101 years with febrile UTIs, during the period January 2012 to December 2014, were analyzed in this multicentre, retrospective cohort study.ResultsThe sensitivities to cefotaxime and cefoxitin were over 85% for females but under 75% for males. Sex played an important role in the susceptibility of GNB to cefotaxime (p<0.001) and cefoxitin (p<0.001). The sensitivity to ciprofloxacin (age >20 years) was under 75% in both sexes, and was not influenced by sex (p=0.204). Age distributions of the incidences of resistance to cefotaxime, cefoxitin, and ciprofloxacin (age >20 years) were similar to the age distribution of the incidence of GNB, which indicates that the resistance patterns to these drugs were not affected by age (Kolmogorovā€“Smirnov test, female/male: p=0.927/p=0.509, p=0.193/p=0.911, and p=0.077/p=0.999, respectively).ConclusionsAge is not a considerable factor in determining the antibiotic resistance in febrile UTIs. Ciprofloxacin should be withheld from both sexes until culture results indicate its use. Second- or third-generation cephalosporins such as cefoxitin and cefotaxime can be used empirically only in females

    Living-donor liver transplantation for giant hepatic hemangioma with diffuse hemangiomatosis in an adult: a case report

    Get PDF
    Hepatic hemangioma represents the most common benign primary hepatic neoplasm. Although most such tumors are small and asymptomatic, giant hepatic hemangioma is frequently symptomatic, and requires intervention. Moreover, diffuse multiple hepatic hemangiomatosis occupying almost the entire liver is extremely rare in adults, and the optimal management for this condition is unclear. We report a case of a rapidly growing, symptomatic giant hepatic hemangioma with diffuse hepatic hemangiomatosis in a 50-year-old female patient who was treated by living-donor liver transplantation. This case shows malignant behavior of a benign hemangioma that required liver transplantation. Although this case could not meet the criteria for transplantation according to the MELD (model for end-stage liver disease) score system, it should be considered as an exceptional indication for deceased-donor liver allocation. Further studies of the mechanism underlying hemangioma growth are warranted
    • ā€¦
    corecore