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Fluvalinate is a widely used and relatively safe acaricide for honeybees, but it still has a negative impact on honeybee colonies. Such negative effects may be related to fluvalinate-induced brain nerve tissue damage, but the detailed molecular regulatory mechanism of this phenomenon is still poorly understood. In this study, we analyzed the miRNA expression profile changes in the brain tissue of Apis mellifera ligustica by miRNA sequencing after fluvalinate treatment. A total of 1,350 miRNAs were expressed in Apis mellifera ligustica brain tissue, of which only 180 were previously known miRNAs in honeybees. Among all known and novel miRNAs, 15 were differentially expressed between at least two of the four time periods before and after fluvalinate administration. Further analysis revealed five significantly enriched KEGG pathways of the differentially expressed miRNA (DEM) potential target genes, namely, “Hippo signaling pathway-fly,” “Phototransduction-fly,” “Apoptosis-fly,” “Wnt signaling pathway,” and “Dorso-ventral axis formation,” which indicates that differentially expressed miRNA function may be related to cell apoptosis and memory impairment in the fluvalinate-treated Apis mellifera ligustica brain. Ame-miR-3477-5p, ame-miR-375-3p, and miR-281-x were identified as key miRNAs. Overall, our research provides new insights into the roles of miRNAs in brain tissue during the process of fluvalinate-induced Apis mellifera ligustica poisoning.

Valuable trees are frequently taken from their original habitat and introduced to a different location in the pursuit of better economic development. Global climate change imposes a higher probability of warm spells during chilly seasons; these may increase the threat posed by frost to newly introduced, valuable species. In this study, Dalbergia odorifera was cultured as a valuable tree species that was introduced from an original provenance in Sanya (1° N) to the northern mountains in Pingxiang (22° N), Guangzhou (23° N), Zhangpu (24° N), Xianyou (25° N), and up to the northernmost limit in Wenzhou (28° N). Seedlings of these six provenances were tested in a field study conducted in Wenzhou (control) to examine their resistance to local frost stress and to detect the driving forces related to meteorological factors in the winter–spring period of 2015–2016. The leaves sampled over seven days exhibited the typical characteristics of frost impairment. The daily maximum temperature delivered warm spells, increasing by ~7 °C. The daily minimum temperature (−4.3 to −2.0 °C) did not reach freezing point until the early spring of 2016. The controlled seedlings showed lower malondialdehyde content than those from the southern locations, and no mortality occurred. Invisible frost stress was caused by low nitrogen utilization during the earlier stages during warm spells, as well as damage to membrane integrity during the later stage when the minimum temperature suddenly declined. A warm spell was found to impose a negative driving force five days before a sudden chill, which led to frost having an impact on superoxide accumulation and electrical leakage. We conclude that the D. odorifera seedlings that dwell effectively in Wenzhou obtained stronger resistance to local frost stress than those from the southern locations. Low cell membrane integrity and high electrical leakage in leaf cells accounted for the frost damage. [ABSTRACT FROM AUTHOR]

We have investigated an adaptive reliability-based iterative soft-decision Reed-Solomon decoding algorithm using belief propagation and we propose a reduced-complexity version of this algorithm. We discuss implementation and performance evaluation of these algorithms on magnetic recording channels. Index Terms--Belief propagation, iterative decoding, magnetic recording, reduced-complexity algorithms, Reed-Solomon codes, reliability-based decoding, soft-decision decoding.

We propose efficient forward recursive algorithms for algebraic soft-decision list decoding of Reed-Solomon codes, which utilize channel reliability information, and outperform the Koetter-Vardy (KV) algorithm with lower decoding latency. We evaluate the performance of the proposed decoding algorithms on additive white Gaussian noise and partial response channels. Simulation results show that we can achieve better performance on a modified extended-extended partial response class 4 channel than on the best possible performance of the KV algorithm, as given by the asymptotic bound for high-rate codes. Index Terms--Generalized minimum distance algorithm, Guruswami-Sudan (GS) algorithm, Koetter-Vardy (KV) algorithm, list decoding, polynomial interpolation, Reed-Solomon (RS) codes, soft-decision decoding, Welch-Berlekamp algorithm.

We report on the application of algebraic soft-decision decoding of Reed-Solomon codes to magnetic recording channels. We present efficient algorithm implementations of the Koetter-Vardy algorithm and introduce a soft version of the Chase algorithm, which expands the decoding list without substantial increase in complexity. Our evaluation of these algorithms, based on realistic simulations on magnetic recording channels, shows that improved performance can be achieved with a small increase in hardware complexity. Index Terms--Error-correction codes, magnetic recording, partial response channels, Reed-Solomon codes, soft Chase algorithm, soft-decision decoding.

The performance of soft-decision Reed-Solomon decoding using belief propagation (BP) is investigated on partial-response equalized magnetic recording channels. A simplification of the BP algorithm, which can be viewed as a Chase-type algorithm, is presented and analyzed. Index Terms--Error correction codes, iterative decoding, magnetic recording, partial response channels, Reed-Solomon codes, soil-decision decoding.

The effects of preceding on the detection of erasures based on violations of run-length-limited (RLL) constraints for low-density parity-check (LDPC) coded magnetic recording channels are investigated and an improved erasure detection algorithm is proposed. Its performance on an [ME.sup.2] PR4 channel is evaluated using computer simulations. Index Terms--BCJR algorithm, erasure, erasure detection, low-density parity-check (LDPC) codes, magnetic recording channels, partial response (PR) channels, precoding, run-length-limited (RLL) codes.

The performance of nested error-correction codes for perpendicular magnetic recording channels is evaluated in the presence of burst noise using Reed-Solomon codes as well as low-density parity-check codes as component codes. Erasure detection and iterative decoding algorithms for nested codes are considered, and their performance is evaluated using computer simulations. The results illustrate the advantages of the nested schemes over noninterleaved architectures in terms of sector error rate and complexity for both current and future native block sizes. Index Terms--Iterative decoding, low-density parity-check codes, nested codes, perpendicular recording, Reed-Solomon codes, soft-decision decoding.

The impact of erasures on the performance of soft-decision Reed-Solomon (RS) decoding for partial-response-equalized magnetic recording channels has been investigated, and the results compared with a similar system using a low-density parity-check (LDPC) code. The system using soft-decision RS decoding exhibits better performance than the one using an LDPC code when the length of a continuous erasure exceeds a certain threshold. Index Terms--Error-correction codes, magnetic recording, partial response (PR) channels, Reed-Solomon codes, soft-decision decoding.

We present a new retry mode scheme for magnetic recording systems based on a soft-decision Reed-Solomon decoding algorithm recently proposed by Koetter and Vardy and evaluate its performance. Instead of using asymptotic bounds, we present realistic simulation results over partial response channels, which show improved performance with a small increase in hardware complexity. Index Terms--Error-correction codes, magnetic recording, partial response channels, Reed-Solomon codes, soft decoding.