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During the investigation of nematode-trapping fungi in Yunnan Province, four strains were isolated from the soil collected in Nujiang City, Yunnan Province, China and were identified as two new Arthrobotrys (Orbiliaceae) species based on morphology and multigene (ITS, EF1-α, and RPB2) phylogenetic analysis. Arthrobotrys gongshanensis is characterized by conidiophores producing 1–5 short denticles near the apex, bearing a single conidium on each denticle and obovoid to fusiform, 1–4-septate conidia. Arthrobotrys luzhangensis is characteristics by its obovoid to fusiform, 1–4-septate macroconidia, and clavate or obovoid, aseptate microconidia. These two new species both capture nematodes using adhesive networks. The multigene phylogenetic analyses further confirmed the taxonomic positions of these two new species within Arthrobotrys. This paper described them with illustrations and compared them with similar taxa.

Arthrobotrys gongshanensis Y.Q Yang & X.Y Yang sp. nov. (FIGURE 2) IndexFungorum: IF559554 Etymology: —The species name “gongshanensis” refers to the name of the sample collection site: Gongshan County, Nujiang City, Yunnan Province, China. Material examined: — CHINA, Yunnan Province, Nujiang City, Gongshan County, from forest soil (27°45'2.46"N 98°40'23.78"W), 1 December 2017, Zhang Fa. (Holotype CGMCC3.23753, deposited in the China General Microbiological Culture Collection Center); ex-type culture DL87. Description: — Saprobic on soil. Colonies white, cottony and grew rapidly on PDA, reaching a colony diameter of 55 mm within 10 days at 26 °C. Mycelium colourless, septate, branched. Conidiophores hyaline, erect, septate, unbranched, produce 1–5 short denticles near the apex and bear single conidium on each denticle, 143–277 μm (x̅= 184 µm, n = 50) long, 3–6 μm (x̅= 3.9 µm, n = 50) wide at the base, 2–4.5 μm (x̅= 3.1 µm, n = 50) wide at apex. Conidia hyaline, smooth, subfusiform to elongate-obovoid, 1–4-septate, mostly 2 or 3-septate, 23–47 × 11.5–23 μm (x̅ = 38 × 16.7 μm, n = 50). Chlamydospores globose to ellipsoidal, chain growth. Capturing nematodes by mean of adhesive networks. Additional material examined: — CHINA, Yunnan Province, Nujiang City, Gongshan County, 27°45’2.46”N 98°40’23.78”E, from forest soil, 1 December 2017, Zhang Fa. Living culture: DLUCC30. Notes: Phylogenetically, Arthrobotrys gongshanensis forms a sister lineage to A. lanpingensis (95% MLBS, 0.92 BYPP). Morphologically, both of them produce subfusiform or elongate-obovoid conidia with 1–4-septate. However, they can be easily distinguished by their conidiophores. The conidiophores of A. gongshanensis produce 1–5 short denticles near the apex and bear 1–5 conidia, while the conidiophores of A. lanpingensis are simple and bear only 1 conidium (Zhang & Hyde 2014)., Published as part of Yang, Yao-Quan, Zhang, Fa, Li, Zheng-Qiang, Zhou, Fa-Ping, Yang, Xiao-Yan & Xiao, Wen, 2023, Morphological and multigene phylogenetic analyses reveal two new nematodetrapping fungi (Arthrobotrys, Orbiliaceae) from Yunnan, China, pp. 263-272 in Phytotaxa 591 (4) on page 268, DOI: 10.11646/phytotaxa.591.4.3, http://zenodo.org/record/7835494, {"references":["Zhang, K. Q. & Hyde, K. D. (2014) Nematode-trapping fungi. Springer Science & Business, Berlin."]}

Arthrobotrys luzhangensis Y.Q Yang & X.Y Yang sp. nov. (FIGURE 3) IndexFungorum: IF559539 Etymology: —The species name “luzhangensis” refers to the name of the sample collection site: Luzhang Town, Nujiang City, Yunnan Province, China. Material examined: — CHINA, Yunnan Province, Lushui County, Luzhang Town, from forest soil (25°56'34.25"N 98°50'21.88"E, 1 December 2017, Zhang Fa. (Holotype CGMCC3.20941, deposited in the China General Microbiological Culture Collection Center); ex-type culture DL117. Description: — Saprobic on soil. Colonies on PDA white, grew rapidly, reaching 55 mm diameter within 7 days at 26 °C. Mycelium colourless, septate, branched. Macroconidiophores hyaline, erect, septate, unbranched, sometimes produce 1–3 short denticles at the apex and bear single macroconidia on each denticle, 115.5–310 μm (x̅= 219.9 µm, n = 50) long, 3.5–5 μm (x̅= 4.8 µm, n = 50) wide at the base, 1.5–3 μm (x̅= 2.5 µm, n = 50) wide at the apex. Microconidiophores erect, septate, unbranched, produce several short denticles by repeated elongation, bear single microconidia on each denticle, 77–180 μm (x̅= 108.7 µm, n = 50) long, 4–5.5 μm (x̅= 4.3 µm, n = 50) wide at the base, 1.5–2.5 μm (x̅= 1.9 µm, n = 50) wide at the apex. Conidia two types: macroconidia hyaline, smooth, obovoid to fusiform, the central cell is the largest,1–4-septate, mostly 2–3-septate, 23.5–67 × 13.5–26.5 μm (x̅ = 49.6 × 20.2 μm, n = 50); Microconidia clavate or obovoid, hyaline, aseptate, 14–23 × 4.5–7.5 μm (x̅ = 18 × 5.7 μm, n = 50). Chlamydospores globose to ellipsoidal, chain growth. Capturing nematodes using adhesive networks. Additional material examined: — CHINA, Yunnan Province, Luzhang Town, Lushui County, 25°56’34.25”N 98°50’21.88”W, from forest soil, 1 December 2017, Zhang Fa. Living culture: DLUCC29. Notes: Phylogenetic analysis revealed that Arthrobotrys luzhangensis is related to A. koreensis, A. obovata, A. scaphoides, A. latisporus, A. botryospora, A. cladodes and A. robusta (91% MLBS, 0.92 BYPP). In morphology, A. luzhangensis (1–4-septate conidia) can be easily distinguished from A. koreensis, A. obovata, A. latisporus, A. botryospora, A. cladodes and A. robusta (0–1-septate conidia) in the shape, size, septation number of conidia (Drechsler 1937, Duddington 1951, Barron 1979, Zhang et al. 1996, Su et al. 2011, Wu et al. 2012, Zhang & Hyde 2014). A. luzhangensis is more similar to A. scaphoides (Schenck et al. 1977). Their differences are as follows: 1) A. luzhangensis produces two types of conidia, while A. scaphoides produce one type conidia; 2) A. scaphoides produce 1–6-septate conidia, while the conidia of A. luzhangensis have no more than 4 septa. In addition, the conidia of A. luzhangensis are shorter and thicker than those of A. scaphoide [A. luzhangensis, 23.6–66.9 (49.6) × 13.5–26.7 (20.2) µm versus A. scaphoide, 36.6–79.3 (57) × 11–17.5 (14) µm]; 3) The conidiophores of A. scaphoide bear 1–10 conidia by repeated elongation, while the conidiophores of A. luzhangensis bear 1–3 conidia on short denticles at the apex., Published as part of Yang, Yao-Quan, Zhang, Fa, Li, Zheng-Qiang, Zhou, Fa-Ping, Yang, Xiao-Yan & Xiao, Wen, 2023, Morphological and multigene phylogenetic analyses reveal two new nematodetrapping fungi (Arthrobotrys, Orbiliaceae) from Yunnan, China, pp. 263-272 in Phytotaxa 591 (4) on pages 269-270, DOI: 10.11646/phytotaxa.591.4.3, http://zenodo.org/record/7835494, {"references":["Duddington, C. L. (1951) Two new predacious hyphomycetes. Transactions of the British Mycological Society 34 (4): 598 - 603. https: // doi. org / 10.1016 / S 0007 - 1536 (51) 80044 - 5","Zhang, K. Q., Liu, X. Z., Cao, L. & Gao, R. H. (1996) A new species of Arthrobotrys from China. Mycological Research 5 (100): 527 - 530. https: // doi. org / 10.1016 / S 0953 - 7562 (96) 80003 - 7","Su, H. Y., Liu, S. R., Li, Y. X. & Cao, Y. H. (2011) Arthrobotrys latispora, a new nematode-trapping fungus from southwest China. Mycotaxon 117 (3): 29 - 36. [https: // www. researchgate. net / publication / 278130299]","Wu, H. Y., Kim, D. G., Ryu, Y. H. & Zhou, X. B. (2012) Arthrobotrys koreensis, a new nematode-trapping species from Korea. Sydowia 64: 129 - 136.","Zhang, K. Q. & Hyde, K. D. (2014) Nematode-trapping fungi. Springer Science & Business, Berlin.","Schenck, S., Kendrick, W. B. & Pramer, D. (1977) A new nematode-trapping hyphomycete and a reevaluation of Dactylaria and Arthrobotrys. Canadian Journal of Botany 55 (8): 977 - 985. https: // doi. org / 10.1139 / b 77 - 115"]}

Well known PS-VA technology has been extensively used for TV application, but the image sticking issue is still a concern. In order to improve the image sticking performance of PS-VA TV panel, the condition of both UV1 and UV2 process are investigated to find out the relationship between the residual amount of RM and the image sticking performance. It shows that the image sticking performance is related to the RM residual amount. As we know, ion density is a factor of image sticking issue. Based on analysis on the relationship between ion density and RM residual amount, we develop a new technology to reduce the image sticking issue in PS-VA mode. Furthermore, another method is provided in this work to improve the image sticking performance by designing a new LC host mixture which has lower residual amount of RM. The technical data is obtained including ion density data measured by Toyo 6254 and surface profile investigation by SEM and AFM.

The photothermal effect and thermal induced photorefraction change of aerosols in the atmosphere were researched.The method to improve detection sensitivity by increasing the number of photothermal effect zones and to reduce the costs by low coherence interferometry was proposed.A mathematics model to measure the aerosol absorption coefficients by photothermal low coherent interferomtry was established,the detection sensitivities from two ways,interferometric orthogonal measurement and interferometric fringe subdividing detecting,were analyzed,and the detecting limit in low coherent polarized interferometry was discussed.Experiments demonstrate that the detection sensitivity in theory can be 1×10-6 m-1.If a longer interaction length and more number interaction zones are choosen,higher sensitivity can be arrived.The theory and method proposed in this paper can provide references for aerosol measurements.