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An error model with asymmetric single error with magnitude four is considered. In this paper, the constructions of codes correcting single error of magnitude four over $\mathbb {Z}_{2^{{a}}3^{{b}}{r}}$ are studied which is equivalent to construct $B_{1}[{4}](2^{{a}}3^{{b}}{r})$ sets. Firstly, we reduce the construction of a maximal size ${B}_{1}[{4}](2^{{a}}3^{{b}}{r})$ set for ${a}\geq 4$ and $ \gcd ({r},6)=1$ to the construction of a maximal size ${B}_{1}[{4}](2^{{a}-3}3^{{b}}{r})$ set. Furthermore, we will show that maximal size ${B}_{1}[{4}](8\cdot 3^{{b}}{r})$ sets can be reduced to maximal size ${B}_{1}[{4}](3^{{b}}{r})$ sets and also give lower bounds of maximal size ${B}_{1}[{4}](12{r})$ and ${B}_{1}[{4}](2\cdot 3^{{b}}{r})$ sets. Finally, we give a necessary and sufficient condition on the existence of perfect ${B}_{1}[{4}]({p})$ set for prime $p$. [ABSTRACT FROM AUTHOR]

Limited magnitude asymmetric error model is well suited for flash memory. In this paper, we consider the construction of asymmetric codes correcting single error over $\mathbb {Z}_{2^{k}r}$ which is based on so called $B_{1}[{4}](2^{k}r)$ set. In fact, we reduce the construction of a maximal size $B_{1}[{4}](2^{k}r)$ set for $k\geq 3$ to the construction of a maximal size $B_{1}[{4}](2^{k-3}r)$ set. Finally, we give an explicit formula of a maximal size $B_{1}[{4}](4r)$ set and some lower bounds of a maximal size $B_{1}[{4}](2r)$ set. By computer searching up to $q\leq 106$ , we conjecture that those lower bounds are tight. [ABSTRACT FROM AUTHOR]

Purpose: The third- or later-line therapy available often yield poor survival benefit in patients metastatic colorectal cancer (mCRC). The retrospective study aimed to evaluate efficacy of rechallenge of oxaliplatin-containing regimens. Patients and methods: Patients with mCRC who progressed from fluoropyrimidine, oxaliplatin, and irinotecan in the first- and second-line chemotherapy, were treated by reexposure to oxaliplatin-containing regimen. Patients treated by anti-epidermal growth factor receptor (EGFR) antibodies with irinotecan were included in the control arm. Results: Ninety-five and 29 patients were treated with either oxaliplatin reexposure or anti-EGFR antibodies with irinotecan, respectively, as the third- or later-line therapy. The median time to treatment failure (TTF) and overall survival (OS) was 3.77 and 12.17 months in the oxaliplatin arm, with 4.77 months of TTF and 11.37 months of OS in the control arm; there was no significance between the 2 arms (p>0.05). Oxaliplatin reexposure resulted in 6.3% objective response rate with no complete response, 6 partial response, 39 stable disease, and 37 progressive disease. The disease control rate was 47.4% (45/95). The multivariate analysis found that patients who achieved disease control by oxaliplatin reexposure had a superior TTF (6.13 vs 1.7 months, p<0.001) and OS (15.73 vs 6.27 months, p<0.001) compared with those presenting with progressive disease. Conclusion: This study showed that rechallenge of oxaliplatin-containing chemotherapy in the third- or later-line therapy may lead to tumor control and improved survival in mCRC patients, which was equivalent to that of anti-EGFR antibodies with irinotecan. Clinical significance: Rechallenge of oxaliplatin-containing regimens in the third- or later-line of therapy is a common practice, despite few evidence available. The present study found that rechallenge of oxaliplatin-containing regimens produced equivalent tumor control and survival benefit to that of anti-EGFR antibodies with irinotecan in mCRC. [ABSTRACT FROM AUTHOR]

[Display omitted] • The second species of Triwangia is described from the Caridina gracilipes. • Phylogenetic analysis positioned this novel species within the "Clade V". • An individual sporophorous vesicle contained up to 62 mature spores. A new microsporidian species was described from the freshwater shrimp Caridina gracilipes collected from Lake Luoma located in Northern Jiangsu province, East China. The infected shrimps appeared generally opaque due to the presence of white cysts located in the connective tissues of the surface of the hepatopancreas. The earliest developmental stages observed were diplokaryotic meronts which were in direct contact with the host cell cytoplasm. Multinucleate sporogonial plasmodia developed into uninucleate sporoblasts which were enclosed in sporophorous vesicles. The parasite developed synchronously within an individual sporophorous vesicle. Mature spores were pyriform and monokaryotic, measuring 5.45 ± 0.18 (5.12–5.82) µm long and 3.57 ± 0.17 (3.18–3.92) µm wide. Anisofilar polar filaments coiled 10–12 turns and arranged in one row. Phylogenetic analysis based on the obtained SSU rDNA sequence indicated that the present species clustered with Triwangia caridina with high support value to form an independent branch which was placed at the basal position of a large clade of containing microsporidia of fishes, crustaceans and amphipods. Based on the morphological characters and ultrastructural features, as well as SSU rDNA-inferred phylogenetic relationships, a new species was erected and named as Triwangia gracilipes n. sp. The taxonomic affiliation of Triwangia was also primarily explored. [ABSTRACT FROM AUTHOR]

In this paper, we propose a mechanism on how to construct long MDS self-dual codes from short ones. These codes are special types of generalized Reed-Solomon (GRS) codes or extended generalized Reed-Solomon codes. The main tool is utilizing additive structure or multiplicative structure on finite fields. By applying this method, more MDS self-dual codes can be constructed. [ABSTRACT FROM AUTHOR]

• The microsporidium Agglomerata daphniae n. sp. is described from Daphnia magna. • Phylogenetic analyses positioned A. daphniae within the "Agglomeratidae" sensu clade. • A daphnia is the first zooplankton-infecting microsporidium in China. A new microsporidian species was described from the hypoderm of Daphnia magna sampled from gibel carp (Carassius auratus gibelio) ponds located in Wuhan city, China. The infected cladocerans generally appeared opaque due to numerous plasmodia distributed in the host integument. The earliest stages observed were uninucleate meronts that were in direct contact with the host cell cytoplasm. Meronts developed into multinucleate sporogonial plasmodia enclosed in sporophorous vesicles. Sporoblasts were produced by the rosette-like division of sporogonial division. Mature spores were pyriform and monokaryotic, measuring 4.48 ± 0.09 (4.34–4.65) µm long and 2.40 ± 0.08 (2.18–2.54) µm wide. The polaroplast was bipartite with loose anterior lamellae and tight posterior lamellae. Polar filaments, arranged in two rows, were anisofilar with two wider anterior coils, and five narrower posterior coils. The exospore was covered with fibrous secretions and was composed of four layers. Phylogenetic analysis based on the obtained SSU rDNA sequence, indicated that the present species clustered with three unidentified Daphnia pulicaria -infecting microsporidia with high support values to form a monophyletic lineage, rather than with the congener, Agglomerata cladocera. The barcode motif of the internal transcribed spacer (ITS) region of the novel species was unique among representatives of the "Agglomeratidae" sensu clade (Vávra et al., 2018). Based on the morphological characters and SSU rDNA-inferred phylogenetic analyses, a new species was erected and named as Agglomerata daphniae n. sp. This is the first report of zooplankton-infecting microsporidia in China. [ABSTRACT FROM AUTHOR]