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The prevalence of obesity in adults and children is rapidly increasing worldwide. Obesity is among the main causes of chronic diseases and various problems, including economic consequences and they can also be affected by genetic, environmental, psychological, and socioeconomic factors. Dietary modification is a well-known and important factor in weight control, in particular, dietary macronutrient composition, food selection, dietary patterns, and energy restriction can affect weight reduction. Therefore, this systematic review aims to provide basic evidence for identifying the optimal macronutrient composition for manag ing obesity in Korean children and adolescents. We searched literature through an international database, stud ies were selected using our eligibility criteria and quality was assessed via a risk of bias tool. In our results, several studies have demonstrated that dietary macronutri ent modifications affect body composition and metabolic markers in children and adolescents. In contrast, hypo caloric diets, regardless of macronutrient composition, are reportedly effective for weight loss in obese children. However, these findings were based on intervention studies that examined the association between dietary macro nutrient compo sition and obesity in non-Korean children and adolescents. Therefore, in the future, more interven tion studies are needed to elucidate this relationship and evidence between macronutrients and obesity in Korean children and adolescents. [ABSTRACT FROM AUTHOR]

Personal data leakages have been experienced by both Indonesia and South Korea. To ensure the protection of privacy rights relating to personal data, both countries have promulgated special laws, namely the Indonesian Personal Data Protection Law (PDP Law) and the South Korean Personal Information Protection Act (PIPA). This study aims to compare the two laws to ascertain their similarities and differences by adopting a comparative law approach. The study found that similarities exist in the two laws. They are to protect personal data and confer rights on data subjects. In the absence of explicit consent given by data subjects, data controllers and processors are prohibited from collecting and processing the data with some exceptions. They also mandate a special institution that is tasked to investigate and sanction data controllers and processors when they conduct data infringement. There are inherent differences in the two laws. PIPA is designed to be the framework legislation and PDP is designed to be a special statute. Additionally, PIPA mandates the institution dealing with personal data protection without referring to any other law but the Act itself. PDP Law clearly states that further provisions relating to this institution will be governed by Presidential Regulation. [ABSTRACT FROM AUTHOR]

Lead-acid batteries (LABs) are widely used as a power source in many applications due to their affordability, safety, and recyclability. However, as the demand for better electrochemical energy storage increases in various fields, there is a growing need for more advanced battery technologies. To meet this need, the application of LABs in hybrid electric vehicles and renewable energy storage has been explored, and the development of lead--carbon batteries (LCBs) has garnered significant attention as a promising solution. LCBs incorporate carbon materials in the negative electrode, successfully addressing the negative irreversible sulfation issue that plagues traditional LABs. Composite material additives and Pb--C composite electrodes have also gained popularity as effective ways to enhance negative electrode performance. This review article focuses on the role of carbon additives in the negative electrode of LCBs and discusses potential future additives that may be incorporated into the development of LCBs. Overall, this article provides insights into the potential of LCBs to offer more efficient and reliable energy storage. [ABSTRACT FROM AUTHOR]

Most organisms on Earth have a biological clock, and their physiological processes are regulated by a 1-day cycle. In modern society, several factors can disturb these biological clocks in humans; in particular, individuals working in shifts are exposed to stark environmental changes that interfere with their biological clock. They have a high risk of various diseases. However, there are scarce experimental approaches to address the reproductive and health consequences of shift work in the offspring of exposed individuals. In this study, considering the fact that shift workers usually have their meals during their adjusted working time, we aimed to examine the effects of a 12-h shift with usual mealtime as a plausible night work model on the neurobehavioral development of adult mouse offspring. In these offspring, early exposure to this mealtime shift differentially affected circadian rhythmic variables and total locomotor activity depending on the timing and duration of restrictive feeding. Moreover, neurobehavioral alterations such as declined short-term memory and depressive-like behavior were observed in adulthood. These results have implications for the health concerns of shift-working women and their children. [ABSTRACT FROM AUTHOR]

Soft, stretchable, conductive thin films have propelled to the forefront of applications in stretchable sensors for on-skin health monitoring. Stretchable conductive films require high conformability, stretchability, and mechanical/chemical stability when integrated into the skin. Here, we present a highly stretchable, conductive, and transparent natural rubber/silver nanowire (AgNW)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) composite film. Overcoating the PEDOT:PSS layer results in outstanding mechanical robustness and chemical stability by suppressing the mechanical and chemical degradation of the nanowire networks. Moreover, the introduction of the organic surface modifier enhances the bonding strength between the natural rubber substrate and AgNW at the interface. The highly conformable composite films are integrated into multifunctional on-skin sensors for monitoring various human motions and biological signals with low-power consumption. We believe that the highly stretchable, robust, and conformable natural rubber/AgNW/PEDOT:PSS composite film can offer new opportunities for next-generation wearable sensors for body motion and physiological monitoring. [ABSTRACT FROM AUTHOR]

An environmental crisis urges people to investigate alternative energy sources for the future. As research on energy conversion and storage increases, electrochemistry is recognized as a sustainable approach for developing renewable energy systems without any emissions. Electrochemical reactions such as hydrogen evolution reaction (HER), ammonia productions, battery systems, and supercapacitors strongly rely on catalysts for their efficiency. In this study, we aim to report the synthesis of nickel phosphide by applying different variables and establishing their correlations with electrochemical reaction outcomes. In contrast to the conventional techniques of analyzing results through material data, this study’s essential part is to obtain higher performance for the HER and supercapacitor with fewer synthesis times through correlation analysis of variables and their outcomes. Accordingly, robust synthesis process design and optimization are expected to reduce cost and time in future research. [ABSTRACT FROM AUTHOR]

The physiological processes of organisms in this rotating planet can adjust according to the time of day via built-in circadian clocks. However, more people are having different shift works, which can increase the risk of pathological conditions including altered reproductive function. Thus, circadian rhythm disturbance has become prevalent in the modern society. Specifically, epidemiological evidence has shown that shift-working women are at high risk of spontaneous abortions, irregular menstrual cycles, and low-birthweight babies. The current study aimed to investigate the effects of circadian rhythm disturbances on the reproductive function of mice caused by dietary time shift, which is common among night-shift workers. According to the schedule of restricted feeding, the mice were classified into the free feeding, daytime feeding, and night feeding groups. The fertility indices of each group were then evaluated. Activity monitoring was performed to determine whether pregnancy delay might be attributed to mealtime shift. Moreover, the estrous cycle of female mice and the reproductive phenotype of male mice were investigated. Results showed that a 12-h mealtime shift significantly delayed successful conception, which could be attributed to a disrupted estrous cycle, in adult female mice. [ABSTRACT FROM AUTHOR]

SWEETs are transporters with homologs in Archeae, plants, some fungi, and animals. As the only transporters known to facilitate the cellular release of sugars in plants, SWEETs play critical roles in the allocation of sugars from photosynthetic leaves to storage tissues in seeds, fruits, and tubers. Here, we report the design and use of genetically encoded biosensors to measure the activity of SWEETs. We created a SweetTrac1 sensor by inserting a circularly permutated green fluorescent protein into the Arabidopsis SWEET1, resulting in a chimera that translates substrate binding during the transport cycle into detectable changes in fluorescence intensity. We demonstrate that a combination of cell sorting and bioinformatics can accelerate the design of biosensors and formulate a mass action kinetics model to correlate the fluorescence response of SweetTrac1 with the transport of glucose. Our analysis suggests that SWEETs are low-affinity, symmetric transporters that can rapidly equilibrate intra- and extracellular concentrations of sugars. This approach can be extended to SWEET homologs and other transporters. [ABSTRACT FROM AUTHOR]

Purpose This study was conducted to determine the effectiveness of immune checkpoint inhibitors (ICIs) in recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC) after platinum-containing chemotherapy. We also identified clinical biomarkers which may be predictive of patient prognosis. Materials and Methods We analyzed 125 patients with R/M HNSCC who received ICIs, retrospectively. Overall response rate (ORR) was the primary study outcome. Overall survival (OS) and progression-free survival (PFS) were the secondary study outcomes. Results The patients received anti-programmed cell death protein-1 (PD-1) (n=73, 58%), anti-programmed death-ligand 1 (PD-L1) (n=24, 19%), or a combination of anti-PD-1/PD-L1 and anti-cytotoxic T-lymphocyte antigen 4 (n=28, 22%). The median age was 57 years (range, 37 to 87). The location of the primary tumor was in the oral cavity in 28% of the cases, followed by oropharynx (27%), hypopharynx (20%), and larynx (12%). The ORR was 15% (19/125). With 12.3 months of median follow-up, median PFS was 2.7 months. Median OS was 10.8 months. A neutrophil-to-lymphocyte ratio (NLR) > 4 was significantly associated with poor response to ICIs (odds ratio, 0.30; p=0.022). A sum of the target lesions > 40 mm (hazard ratio [HR], 1.53; p=0.046] and a NLR > 4 (HR, 1.75; p=0.009) were considered to be predictive markers of short PFS. A poor performance status (HR, 4.79; p < 0.001), a sum of target lesions > 40 mm (HR, 1.93; p=0.025), and an NLR > 4 (HR, 3.36; p < 0.001) were the significant predictors for poor survival. Conclusion ICIs exhibited favorable antitumor activity in R/M HNSCC. Clinically, our findings can be used to recognize patients benefit from receiving ICI. [ABSTRACT FROM AUTHOR]

Freeman-Sheldon syndrome (FSS) is a rare distal arthrogryposis syndrome. There are few reports on the respiratory insufficiency of FSS. Additionally, there is no detailed information on pulmonary functional evaluation. A 17-year-old male patient with FSS developed respiratory failure, leading him to be admitted to hospital several times for evaluation and treatment. Of those times he was admitted, two were due to pneumonia. His pulmonary functions were indicative of a restrictive lung disease potentially caused by severe scoliosis. After a non-invasive ventilatorwas applied correctly to the patient, pulmonary hypertension was normalized. His pulmonary function has been maintained for 13 years. Since receiving proper respiratory care, which includes assisted coughing methods, the patient has not developed pneumonia. It is important to properly evaluate the pulmonary function of patients who have FSS and scoliosis to eliminate the risk of long-term respiratory complications. [ABSTRACT FROM AUTHOR]

Objective: Paraoxonase 1 (PON1), a calcium-dependent serum enzyme, has been shown to be involved in lipid metabolism. In this study, we examined the putative correlation of the serum PON1 level of Hanwoo, Korean native cattle, with gender and meat quality grade. Methods: PON1 levels were estimated by determining the arylesterase and paraoxonase activities (AE and PO, respectively) in serum samples from Hanwoo individuals (n = 56). Serum PON1 levels were analyzed in different gender groups (female [n = 21], castrated male [n = 17], and male [n = 18]), and meat quality grades (≥1 [n = 23], 2 [n = 21], and 3 [n = 12]). Results: Serum PON1 levels were similar in female (AE = 120±55 U/mL, PO = 84±43 mU/mL) and castrated male (123±44 U/mL, PO = 89±30 mU/mL), while male showed a significantly lower level (AE = 65±43 U/mL, PO = 44±34 mU/mL). Furthermore, analysis of serum PON1 levels in three different grades of meat quality showed similar levels in the grades ≥1 (AE = 118±49 U/mL, PO = 84±37 mU/mL) and 2 (AE = 116±54 U/mL, PO = 82±43 mU/mL), while the level was significantly lower in the grade 3 (AE = 58±35 U/mL, PO = 39±27 mU/mL) of lower meat quality. Conclusion: We discovered the gender-dependent differences in serum PON1 levels of Hanwoo and a positive association of the serum PON1 level with meat quality. Results in this study suggest that PON1 would be a useful serum marker for preliminary screening of Hanwoo individuals with high-quality meat and applicable for genetic improvement. [ABSTRACT FROM AUTHOR]

Objective To investigate and demonstrate persistent increase of peak cough flow after mechanical in-exsufflator application, in patients with neuromuscular diseases and pneumonia. Methods A mechanical in-exsufflator was applied with patients in an upright or semi-upright sitting position (pressure setting, +40 and -40 cmH2O; in-exsufflation times, 2-3 and 1-2 seconds, respectively). Patients underwent five cycles, with 20-30 second intervals to prevent hyperventilation. Peak cough flow without and with assistive maneuvers, was evaluated before, and 15 and 45 minutes after mechanical in-exsufflator application. Results Peak cough flow was 92.6 L/min at baseline, and 100.4 and 100.7 L/min at 15 and 45 minutes after mechanical in-exsufflator application, respectively. Assisted peak cough flow at baseline, 15 minutes, and 45 minutes after mechanical in-exsufflator application was 170.7, 179.3, and 184.1 L/min, respectively. While peak cough flow and assisted peak cough flow increased significantly at 15 minutes after mechanical in-exsufflator application compared with baseline (p=0.030 and p=0.016), no statistical difference was observed between 15 and 45 minutes. Conclusion Increased peak cough flow after mechanical in-exsufflator application persists for at least 45 minutes. [ABSTRACT FROM AUTHOR]

Background/Objectives: The purpose of this study is to evaluate the current curriculum related to school music education and predict what kind of research is needed in future. Methods/Statistical analysis: In order to achieve the purpose of this study, we analyzed the tendency of 1,000 research materials related to music curriculums. Research material included research articles, research reports, doctoral dissertations, and other related material. This was analyzed in terms of research period, research topics, research subjects, and research methods. Findings: The results of the study are as follows. In recent years, research topics have been segmented and specialized. Various topics related to curriculum planning, development, and implementation has been studied. The subjects of this study were mainly curriculum document based or about elementary, middle, and high school curriculums. Methodologically, literary research was conducted. The future will have to support a more research-oriented macro perspective, music curriculums that reflect the social needs, fluent planning and execution between related studies, broadening of study subjects, and diversification of methods. Improvements/Applications: This study is meaningful due to the direction it gives the academic curriculum which occupies an important part of school music education to improve in the future. [ABSTRACT FROM AUTHOR]

Objective To report the latest long-term outcome of amyotrophic lateral sclerosis (ALS) and to analyze the predictors of prognosis. Methods Subjects who were diagnosed with ALS between January 2005 and December 2009 at a single institute were followed up until death or up to December 2014. Data regarding age, sex, date of onset, date of diagnosis, presence of bulbar symptoms on onset, date of initiation of non-invasive ventilation (NIV), and the date of tracheostomy were collected. Survival was assessed using Kaplan-Meier curves and multivariate analyses of the risk of death were performed using the Cox proportional hazards model. Results Among 212 suspicious subjects, definite ALS was diagnosed in 182 subjects. The survival rate at 3 and 5 years from onset was 61.5% and 40.1%, respectively, and the survival rate at 3 and 5 years post-diagnosis was 49.5% and 24.2%, respectively. Further, 134 patients (134/182, 73.6%) were initiated on NIV, and among them, 90 patients (90/182, 49.5%) underwent tracheostomy. Male gender and onset age of ≥65 years were independent predictors of adverse survival. Conclusion The analysis of long term survival in ALS showed excellent outcomes considering the overall poor prognosis of this disease. [ABSTRACT FROM AUTHOR]

Electron-beam irradiation (EBI) was used to remove phenol in aqueous solution. The removal efficiencies of phenol were determined, and their relationships with the initial phenol concentration, absorbed dose, and electron-beam energy were investigated. The EBI was conducted in air with absorbed doses from 40 to 120 kGy under 0.3, 1, and 2 MeV electron beams. G-values were introduced to evaluate the removal of phenol quantitatively and were higher at an absorbed dose of 40 kGy than at 80 or 120 kGy. Dose constants (K) were found to depend on the absorbed dose and initial phenol concentration and used to calculate the optimum doses required for 90% (D0.9) and 50% (D0.5) removal of phenol. The reduction of the biochemical oxygen demand (BOD5), chemical oxygen demand (CODCr), and total organic carbon (TOC) via EBI indicated organic degradation upon irradiation. The EBI process was combined with activated carbon fiber (ACF) adsorption to improve the CODCr removal efficiency. The optimum ACF doses were 0.5, 1.0, and 1.33 g L-1 with 3, 6, and 6 h contact times for the 20, 50, and 100 mg L-1 phenol solutions, respectively. The combination of EBI with ACF improved the CODCr removal efficiency, even in the more concentrated phenol solution. EBI may be a promising pretreatment process for purifying highly concentrated wastewater. [ABSTRACT FROM AUTHOR]

Background: Total intravenous anesthesia (TIVA) is used widely in spinal surgery because inhalational anesthetics are known to decrease the amplitude of motor evoked potentials. Presently, dexmedetomidine is used as an adjuvant for propofol-based TIVA. We compared the effects of remifentanil and dexmedetomidine on pain intensity as well as the analgesic requirements after post-anesthesia care unit (PACU) discharge in patients undergoing spinal surgery. Methods: Forty patients scheduled for posterior lumbar interbody fusion (PLIF) surgery under general anesthesia were enrolled. Anesthesia was maintained using propofol at 3-12 mg/kg/h and remifentanil at 0.01-0.2 µg/kg/min in Remifentanil group or dexmedetomidine at 0.01-0.02 µg/kg/min in Dexmedetomidine group, keeping the bispectral index between 40 and 60. Patient-controlled analgesia (PCA) made of hydromophone was applied once the patients opened their eyes in the PACU. The visual analog scale (VAS) score, PCA dosage administered, and postoperative nausea and vomiting (PONV) were recorded at the time of discharge from the PACU (T1) and at 2 (T2), 8 (T3), 24 (T4), and 48 hours (T5) after surgery. Results: The VAS score in Remifentanil group was significantly higher than that in Dexmedetomidine group at immediate and late postoperative period (4.1 ± 2.0 vs. 2.3 ± 2.2 at T1, and 4.0 ± 2.2 vs. 2.6 ±1.7 at T5; P < 0.05). Dexmedtomidine group had a statistically significantly lower PCA requirement at every time point after surgery except directly before discharge from the PACU (3.0 ± 1.2 ml vs. 2.3 ± 1.4 ml at T1; P>0.05, but 69.7 ±21.4 ml vs. 52.8 ± 10.8 ml at T5; P < 0.05). Patients in Remifentanil group displayed more PONV until 24 hours post-surgery. Conclusions: Dexmedetomidine displayed superior efficacy in alleviating pain and in postoperative pain management for 48 hours after PLIF. Therefore, dexmedetomidine may be used instead of remifentanil as an adjuvant in propofol-based TIVA. Trial registration: Clinical Research Information Service (CRiS) Identifier: KCT0001041. [ABSTRACT FROM AUTHOR]

The inherent attenuation of a homogeneous viscous medium limits radiation propagation, thereby restricting the use of many high-frequency acoustic devices to only short-range applications. Here, we design and experimentally demonstrate an acoustic metamaterial localization cavity which is used for sound pressure level (SPL) gain using double coiled up space like structures thereby increasing the range of detection. This unique behavior occurs within a subwavelength cavity that is 1/10th of the wavelength of the incident acoustic wave, which provides up to a 13 dB SPL gain. We show that the amplification results from the Fabry-Perot resonance of the cavity, which has a simultaneously high effective refractive index and effective impedance. We also experimentally verify the SPL amplification in an underwater environment at higher frequencies using a sample with an identical unit cell size. The versatile scalability of the design shows promising applications in many areas, especially in acoustic imaging and underwater communication. [ABSTRACT FROM AUTHOR]

The article presents a study focusing on attenuation of migration properties of CD4+ T cells from aged mice which correlate with the decrease in chemokine receptor expression, response to retinoic acid (RA), and RALDH expression when compared to young mice. The finding include the decreased expression of RALDH2 mRNA in mesenteric lymph node dendritic cells of aged mice, the migration abilities of CD4+ T cells, and the declined response to RA by aged mice.

Background: The hang-back surgery is a useful technique in the field of strabismus surgery. The aim of this study is to determine the stabilizing effects of fibrin glue as an adjuvant to hang-back surgery.Materials and methods: Four (4)-mm hang-back recessions of the superior rectus muscle was performed in 32 eyes of 16 rabbits. Only in the left eye of the 16 rabbits, fibrin glue was applied between the recessed muscle bed and the sclera at the end of hang-back surgery (fibrin glue group). After 6 weeks, we compared the stability of the recessed rectus muscle between the fibrin glue group and the control group by evaluating the displacement of the muscle. Results: The frequency of stable insertion of the recessed muscle at the intended site was greater in the fibrin glue group (9 eyes) compared to the control group (3 eyes) (p = 0.028). In the control group, 5 eyes showed anterior displacement and 8 eyes showed posterior displacement and in the fibrin glue group, 1 eye showed anterior displacement, and 6 eyes showed posterior displacement. Anterior displacement was more common in the control group (6.3% Vs 31.3%). The control group and the fibrin glue group showed similar histological findings on microscopic examination. Conclusions: Fibrin glue is effective in stabilizing the new rectus muscle insertion and decreasing the displacement in the hang-back surgery. [ABSTRACT FROM AUTHOR]

In this article, a CMOS multistandard wireless direct-conversion receiver is designed. The receiver is composed of three components: low noise amplifier, voltage-controlled oscillator, and mixer. In details, the designed receiver adopts direct-conversion architecture and accommodates three standards: WCDMA, Wibro (or mobile WIMAX), and CDMA 2000 1×: 1.84–2.4 GHz. The designed mixer is a passive sub-harmonic doubly balanced structure, the VCO is a back-gate coupling quadrature VCO, and the LNA is a differential structure. Each component is designed with relevance to direct-conversion architecture. The designed mixer has no flicker noise theoretically because the mixing transistors operate in the triode region. Also, DC offset problem is avoided, because local oscillator frequency is half of RF frequency and the port isolation is improved by the innate characteristic of a balanced structure. The VCO generates a quadrature signal and the oscillation frequency is half of RF frequency to drive designed sub-harmonic mixer. No coupling transistors are needed due to the use of back-gate coupling to reduce flicker noise. Back-gate coupling means that the body of a transistor is used as another gate. The LNA, which adopts a well-known cascade structure, is designed as a differential structure to suppress common mode noise and to drive a doubly balanced mixer. All designed components are fabricated by the TSMC 0.18-μm RF CMOS process. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 718–721, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24989 [ABSTRACT FROM AUTHOR]

The bit error rate of an underwater acoustic communication system is related to multipath fading statistics, which determine the signal-to-noise ratio. The amplitude and delay of each path depend on sea surface roughness, propagation medium properties, and source-to-receiver range as a function of frequency. Therefore, received signals will show frequency-dependent fading. A shallow-water acoustic communication channel generally shows a few strong multipaths that interfere with each other and the resulting interference affects the fading statistics model. In this study, frequency-selective fading statistics are modeled on the basis of the phasor representation of the complex path amplitude. The fading statistics distribution is parameterized by the frequency-dependent constructive or destructive interference of multipaths. At a 16 m depth with a muddy bottom, a wave height of 0.2 m, and source-to-receiver ranges of 100 and 400 m, fading statistics tend to show a Rayleigh distribution at a destructive interference frequency, but a Rice distribution at a constructive interference frequency. The theoretical fading statistics well matched the experimental ones. [ABSTRACT FROM AUTHOR]

Anyons, quasiparticles living in two-dimensional spaces with exotic exchange statistics, can serve as the fundamental units for fault-tolerant quantum computation. However, experimentally demonstrating anyonic statistics is a challenge due to the technical limitations of current experimental platforms. Here, we take a state perpetration approach to mimic anyons in the toric code using a seven-qubit nuclear magnetic resonance quantum simulator. Anyons are created by dynamically preparing the ground and excited states of a seven-qubit planar version of the toric code, and are subsequently braided along two distinct, but topologically equivalent paths. We observe that the phase acquired by the anyons is independent of the path, and coincides with the ideal theoretical predictions when decoherence and implementation errors are taken into account. As the first demonstration of the topological path independence of anyons, our experiment helps to study and exploit the anyonic properties towards the goal of building a topological quantum computer. [ABSTRACT FROM AUTHOR]

Transmitted signals are markedly affected by sea surface and bottom boundaries in shallow water. The time variant reflection signals from such boundaries characterize the channel as a frequency-selective fading channel and cause intersymbol interference (ISI) in underwater acoustic communication. A channel-estimate-based equalizer is usually adopted to compensate for the reflected signals under this kind of acoustic channel. In this study, we apply two approaches for packet and continuous data transmission of the quadrature phase shift keying (QPSK) system. One is the use of a two-dimensional (2D) rotation matrix in a non-frequency-selective channel. The other is the use of two equalizers of types — the feed forward equalizer (FFE) and decision-directed equalizer (DDE) — with a normalized least mean square (NLMS) algorithm in a frequency-selective channel. The percentage improvement of packet transmission is notably better than that of continuous transmission. [ABSTRACT FROM AUTHOR]

In underwater acoustic communication, the transmitted signal is affected by multipath fading and background noise. Therefore, the intersymbol interference (ISI) of underwater acoustic communication systems depends on the effects of these parameters. To cope with ISI due to multipath fading, various equalizers and orthogonal frequency division multiplexing systems have been developed. Forward error correction coding is also adopted to reduce the error by background noise. Here, the performances of convolution code (CC) and Reed–Solomon (RS) code are evaluated in a multipath fading channel. The CC shows better performance in frequency nonselective fading but the RS code shows better performance in frequency selective fading. [ABSTRACT FROM AUTHOR]