Getah virus (GETV), an arthropod-borne virus transmitted by mosquitoes, has been isolated from several animals. GETV infection in horses shows clinical signs such as fever, rash, and edema in the leg.

horses are one of the eight Japanese native horses. The present study aimed to clarify the occurrence of GETV infection in horses. Serum samples collected from horses were analyzed using a virus neutralization test and enzyme-linked immunosorbent assay and showed that the anti-GETV antibody titers in the samples collected in 2017 were significantly higher than those collected in 2012. We concluded that a seroconversion of anti-GETV antibodies was occurred in the horse population around 2012, providing evidence of the GETV epidemic in Japan circa 2012.

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In the 5th-generation mobile communication system (5G), a multiuser multiplexing scheme, nonorthogonal multiple access (

), has been proposed to accommodate the massive connectivity in wireless communication systems. By nonorthogonality, allows the use of a new domain that is ineffectively utilized in conventional orthogonal multiple access (OMA) schemes. In power-domain (PD-), user signals are allocated different power levels and multiplexed by superposition coding at a transmitter. employs interference cancellation schemes such as successive interference cancellation (SIC) at receivers to avoid interference between the signals. The use of nonlinear systems such as low-resolution analog-to-digital converters (ADCs) is favorable in terms of energy consumption since the load of SIC processes increases proportionally to the number of users. However, on the other hand, the use of nonlinear systems leads to the degradation of signal detection performance. Stochastic resonance (SR) is a nonlinear phenomenon that improves the response of nonlinear systems to weak power signals. In this paper, we propose the application of SR to the nonlinear system in SIC. Through computer simulations, we show that the proposed method can improve the signal detection performance without losing the advantage of low energy consumption.

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The

horse is a Japanese breed from the region of Imabari City, Ehime Prefecture. To obtain reference hematological and biochemical values, we performed examinations in 39 clinically healthy, mature horses managed at the Imabari public ranch. Hematological and biochemical results of horses were close to the normal ranges of horses in the U.S.A. The erythrocyte parameters and hepatobiliary enzyme levels in and Kiso horses were lower than those in Japanese racehorses. horses showed higher erythrocyte parameters and triglyceride concentrations and a lower creatinine concentration compared with those in Kiso horses. These data represent the first report of reference values for horses and may be useful to improve their management.

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Uplink non-orthogonal multiple access (

) has attracted considerable attention as a key technology for beyond 5G/6G telecommunication. However, when adopting the uplink in multi-cell networks where an uplink signal may reach multiple base stations (BSs), the successive interference cancellation (SIC) process must be completed at every BS, resulting in smaller throughput owing to bottlenecks. To cope with this issue, we propose a novel approach called cooperative-SIC (C-SIC), where SIC processes at different BSs are mutually combined by exploiting signal transfer through backhaul links, which can prevent some signals from experiencing bottlenecks. Through performance comparison with the conventional , we reveal the significant potential of C-SIC for the uplink in a multi-cell network.

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Non-orthogonal multiple access () utilizing the power domain and advanced receiver has been considered as one promising multiple access technology for further cellular enhancements toward the 5th generation (5G) mobile communications system. Most of the existing investigations into focus on the combination of with orthogonal frequency division multiple access (OFDMA) for either downlink or uplink. In this paper, we investigate for uplink with single carrier-frequency division multiple access (SC-FDMA) being used. Differently from OFDMA, SC-FDMA requires consecutive resource allocation to a user equipment (UE) in order to achieve low peak to average power ratio (PAPR) transmission by the UE. Therefore, sophisticated designs of scheduling algorithm for with SC-FDMA are needed. To this end, this paper investigates the key issues of uplink scheduling such as UE grouping method and resource widening strategy. Because the optimal schemes have high computational complexity, novel schemes with low computational complexity are proposed for practical usage for uplink resource allocation of with SC-FDMA. On the basis of the proposed scheduling schemes, the performance of is investigated by system-level simulations in order to provide insights into the suitability of using for uplink radio access. Key issues impacting performance are evaluated and analyzed, such as scheduling granularity, UE number and the combination with fractional frequency reuse (FFR). Simulation results verify the effectiveness of the proposed algorithms and show that is a promising radio access technology for 5G systems.

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This paper presents our investigation of non-orthogonal multiple access () as a novel and promising power-domain user multiplexing scheme for future radio access. Based on information theory, we can expect that with a successive interference canceller (SIC) applied to the receiver side will offer a better tradeoff between system efficiency and user fairness than orthogonal multiple access (OMA), which is widely used in 3.9 and 4G mobile communication systems. This improvement becomes especially significant when the channel conditions among the non-orthogonally multiplexed users are significantly different. Thus, can be expected to efficiently exploit the near-far effect experienced in cellular environments. In this paper, we describe the basic principle of in both the downlink and uplink and then present our proposed scheme for the scenario where the base station is equipped with multiple antennas. Simulation results show the potential system-level throughput gains of relative to OMA.

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This paper investigates a downlink non-orthogonal multiple access () combined with single user MIMO (SU-MIMO) for future LTE (Long-Term Evolution) enhancements. In particular, we propose practical schemes to efficiently combine with open-loop SU-MIMO (Transmission Mode 3: TM3) and closed-loop SU-MIMO (Transmission Mode 4: TM4) specified in LTE. The goal is also to clarify the performance gains of combined with SU-MIMO transmission, taking into account the LTE radio interface such as frequency-domain scheduling, adaptive modulation and coding (AMC), and specific functionalities such as, multi-user pairing/ordering, transmit power allocation and successive interference cancellation (SIC) at the receiver side. Based on computer simulations, we evaluate link-level performance and show that the impact of error propagation associated with SIC is marginal when the power ratio of cell-edge and cell-center users is sufficiently large. In addition, we evaluate system-level performance gains for different granularities of scheduling and MCS (modulation and coding scheme) selection, for both genie-aided channel quality information (CQI) estimation and approximated CQI estimation, and using different number of power sets. Evaluation results show that combined with SU-MIMO can still provide a hefty portion of its expected gains even with approximated CQI estimation and limited number of power sets, and also when LTE compliant subband scheduling and wideband MCS is applied.

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The objective of this study is to analyze the relationships between the age and blood test results or body sizes in

horses by using the results of periodical health examination. Out of 45 hematological or physical items examined, statistically significant, but loose correlations were observed in 14 items. Red blood cell count, activities of aspartate aminotransferase, alkaline phosphatase, and creatinine kinase, concentrations of calcium and inorganic phosphorus decreased with aging. Conversely, mean corpuscular volume, mean corpuscular hemoglobin, lipase activity, γ-globulin and chloride concentrations, body height, chest circumference and cannon bone circumference increased with aging. The changes in a few items seemed unique to horse. However, most age-related changes found in this study might be considered as a common trend in horse breeds rather than distinctive characteristic in horse.

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Non-orthogonal multiple access (

), which combines multiple user signals and transmits the combined signal over one channel, can achieve high spectral efficiency for mobile communications. However, combining the multiple signals can lead to degradation of bit error rates (BERs) of under severe channel conditions. In order to improve the BER performance of , this paper proposes a new scheme based on orthogonal space-time block codes (OSTBCs). The proposed scheme transmits several multiplexed signals over their respective orthogonal time-frequency channels, and can gain diversity effects due to the orthogonality of OSTBC. Furthermore, the new scheme can detect the user signals using low-complexity linear detection in contrast with the conventional . The paper focuses on the Alamouti code, which can be considered the simplest OSTBC, and theoretically analyzes the performance of the linear detection. Computer simulations under the condition of the same bit rate per channel show that the Alamouti code based scheme using two channels is superior to the conventional using one channel in terms of BER performance. As shown by both the theoretical and simulation analyses, the linear detection for the proposed scheme can maintain the same BER performance as that of the maximum likelihood detection, when the two channels have the same frequency response and do not bring about any diversity effects, which can be regarded as the worst case.

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Multiple access (MA) technology is of most importance for beyond long term evolution (LTE) system. Non-orthogonal multiple access () utilizing power domain and advanced receiver has been considered as a candidate MA technology recently. In this paper, power assignment method, which plays a key role in performance of , is investigated. The power assignment on the basis of maximizing geometric mean user throughput requires exhaustive search and thus has an unacceptable computational complexity for practical systems. To solve this problem, a novel power assignment method is proposed by exploiting tree search and characteristic of serial interference cancellation (SIC) receiver. The proposed method achieves the same performance as the exhaustive search while greatly reduces the computational complexity. On the basis of the proposed power assignment method, the performance of is investigated by link-level and system-level simulations in order to provide insight into suitability of using for future MA. Simulation results verify effectiveness of the proposed power assignment method and show is a very promising MA technology for beyond LTE system.

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Non-orthogonal multiple access (

) allows several users to multiplex in the power-domain to improve spectral efficiency. To further improve its performance, it is desirable to reduce inter-user interference (IUI). In this paper, we propose a downlink asynchronous (ANOMA) scheme applicable to frequency-selective channels. The proposed scheme introduces an intentional symbol offset between the multiplexed signals to reduce IUI, and it employs cyclic-prefixed single-carrier transmission with frequency-domain equalization (FDE) to reduce inter-symbol interference. We show that the mean square error for the FDE of the proposed ANOMA scheme is smaller than that of a conventional scheme. Simulation results show that the proposed ANOMA with appropriate power allocation achieves a better sum rate compared to the conventional .

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A Low-Density Code Structure (LDC) spread transmission for Non-Orthogonal Multiple Access (

) system based on modified combinatorial design is studied in this letter. To mitigate the multiuser access interference, the frequently needs complicated signal processing, which is difficult to be applied in practical scenarios. One potential solution is to design sparse multiple access structure for leveraging detection complexity. The sparse pattern of Balanced Incomplete Block Designs (BIBDs) provide an inherent sparse mapping for this system allowing simultaneous and more efficient usage of given. It is also able to form a bijection mapping with lower complexity and be reconstrued to achieve further sparsity. This new scheme allows a larger number of users transmitting in the downlink.

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This letter presents a non-orthogonal multiple access (

) technique for a two-cell multiple-input multiple-output (MIMO) system that exploits the alignments of inter-cell interference channels and signal channels within a cluster in a cell. The proposed technique finds combiner vectors for users that align the inter-cell interference channels and the signal channels simultaneously. This technique utilizes the aligned interference and signal channels to obtain precoder matrices for base stations through which each data stream modulated by can be transmitted to the intended cluster without interference. In addition, we derive the sufficient condition for transmit and receive antenna configurations in the MIMO systems to eliminate inter-cell interference and inter-cluster interference simultaneously. Because the proposed technique effectively suppresses the inter-cell interference, it achieves a higher degree of freedom than the existing techniques relying on an avoidance of inter-cell interference, thereby obtaining a better sum rate performance in high SNR regions. Furthermore, we present the hybrid MIMO technique, which combines the MIMO technique exploiting channel alignment with the existing techniques boosting the received signal powers. Using the benefits from these techniques, the proposed hybrid technique achieves a good performance within all SNR regions. The simulation results successfully demonstrate the effectiveness of the proposed techniques on the sum rate performance.

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Non-orthogonal multiple access (

) makes multiple mobile users share the same frequency band. In a conventional scheme, a user pair that can be assigned to the same frequency resource is limited, which reduces the amount of capacity improvement possible. This is because a far user demodulates a signal without canceling an underlaid signal for a near user. In addition, semi-orthogonal multiple access (SOMA) modulation has been proposed. This modulation scheme helps to reduce scheduling complexity and demodulation complexity. In this paper, a joint detection scheme is applied to a far user as well as a near user in a downlink. The joint detection in the far user leads to a more number of user pairs that can be assigned to the same frequency resource through proportional fair scheduling. The total system throughput performance with the joint detection is evaluated with multi-cell system level simulation. Numerical results show that the joint detection in the original system increases the system throughput more effectively than that with SOMA modulation.

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The horse breed is the smallest among the eight native Japanese horse breeds. The population of horses has been decreasing consistently, and they are listed as a critical breed; thus, conservation measures are urgently required. In this study, we estimated the pedigree-based inbreeding (FPED) and genomic inbreeding coefficients (FIS and FROH) of 24 horses bred in Imabari City, Ehime Prefecture. We used 65 K equine SNP chip (GeneSeek/Neogen) data, and identified a total of 31,133 autosomal SNP genotypes after quality control steps. They were used to estimate the genomic inbreeding coefficient. We found that two full siblings had identical FPED (0.303) and different FIS (-0.157 and 0.077). When the mean FIS value was compared between this study (-0.098) and the previous study (Kakoi et al. 2007) (-0.130), this study had higher inbreeding values. A total of 815 ROH segments larger than 1 Mb were identified in 24 horses, and 78.7% of them were longer than 4 Mb, confirming recent inbreeding in this population. FROH (FROH–All, FROH1–2Mb, FROH2–4Mb, FROH4–8Mb, FROH8–16Mb, FROH> 16Mb) was calculated for different ROH lengths (all segments, 1–2, 2–4, 4–8, 8–16, and > 16 Mb, respectively). These estimates increased with increasing ROH length suggesting higher inbreeding in recent generations.

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In fifth-generation mobile communications systems (5G), grant-free non-orthogonal multiple access (

) schemes have been considered as a way to accommodate the many wireless connections required for Internet of Things (IoT) devices. In schemes, both system capacity enhancement and transmission protocol simplification are achieved, and an overload test of more than one hundred percent of the transmission samples over conducted. Multi-user shared multiple access (MUSA) has been proposed as a representative scheme for . However, the performance of MUSA has not been fully analyzed nor compared to other or orthogonal multiple access schemes. Therefore, in this study, we theoretically and numerically analyze the performance of MUSA in uplink fading environments and compare it with orthogonal frequency division multiple access (OFDMA), space division multiple access-based OFDMA, low-density signature, and sparse code multiple access. The characteristics and superiority of MUSA are then clarified.

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The impact of multiple antennas on a hybrid multiple access scheme was investigated considering the desired user traffic volume as well as channel conditions. In the proposed approach, by using both non-orthogonal multiple access (

) and orthogonal multiple access (OMA) in the same bandwidth, a resource pattern combined with different user requirements is introduced to effectively meet the demands of diversified wireless services beyond 5G. In this study, maximum ratio transmission (MRT) is applied to and OMA, considering that recent base stations (BSs) are equipped with multiple antennas. Thus, the spatial diversity gain is considered when calculating the actual throughput used for choosing the best resource pattern. The effectiveness of the proposed scheme is demonstrated through computer simulations by considering the antenna configuration under diversified user traffic for enhanced mobile broadband (eMBB) and ultra-reliable and low-latency communications (URLLC).

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This paper investigates the system-level throughput of non-orthogonal multiple access () with a successive interference canceller (SIC) in the cellular downlink assuming proportional fair (PF)-based radio resource (bandwidth and transmission power) allocation. The purpose of this study is to examine the possibility of applying with a SIC to the systems beyond the 4G cellular system. Both the mean and cell-edge user throughput are important in a real system. PF-based scheduling is known to achieve a good tradeoff between them by maximizing the product of the user throughput among users within a cell. In with a SIC, the scheduler allocates the same frequency to multiple users simultaneously, which necessitates multiuser scheduling. To achieve a better tradeoff between the mean and cell-edge user throughput, we propose and compare three power allocation strategies among users, which are jointly implemented with multiuser scheduling. Extensive simulation results show that with a SIC with a moderate number of non-orthogonally multiplexed users significantly enhances the system-level throughput performance compared to orthogonal multiple access (OMA), which is widely used in 3.9 and 4G mobile communication systems.

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Non-orthogonal multiple access (

) enables multiple mobile devices to share the same frequency band. In a conventional scheme, the receiver of a far user detects its desired signal without canceling the signal for a near user. However, the signal for the near user acts as interference and degrades the accuracy of likelihood values for the far user. In this paper, a joint maximum likelihood detection scheme for the far user of the downlink is proposed. The proposed scheme takes the interference signal into account in calculating the likelihood values. Numerical results obtained through computer simulation show that the proposed scheme improves the performance by from 0.2dB to 3.1dB for power allocation coefficients of 0.2 to 0.4 at a bit error rate (BER) of 10^-2 relative to the conventional scheme.

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This paper extends our previously proposed non-orthogonal multiple access () scheme to the base station (BS) cooperative multiple-input multiple-output (MIMO) cellular downlink for future radio access. The proposed scheme employs intra-beam superposition coding of a multiuser signal at the transmitter and the spatial filtering of inter-beam interference followed by the intra-beam successive interference canceller (SIC) at the user terminal receiver. The intra-beam SIC cancels out the inter-user interference within a beam. This configuration achieves reduced overhead for the downlink reference signaling for channel estimation at the user terminal in the case of non-orthogonal user multiplexing and enables the use of the SIC receiver in the MIMO downlink. The transmitter beamforming (precoding) matrix is controlled based on open loop-type random beamforming using a block-diagonalized beamforming matrix, which is very efficient in terms of the amount of feedback information from the user terminal. Simulation results show that the proposed scheme with block-diagonalized random beamforming in BS cooperative multiuser MIMO and the intra-beam SIC achieves better system-level throughput than orthogonal multiple access (OMA), which is assumed in LTE-Advanced. We also show that BS cooperative operation along with the proposed further enhances the cell-edge user throughput gain which implies better user fairness and universal connectivity.

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