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Controlling hybrid material properties by simple monomer design offers an elegant pathway to prepare thermoset adhesives with tunable properties. Herein, biobased hybrid polyhydroxyurethane/polyepoxy is prepared starting from partially carbonated cashew nut shell epoxy derivatives (NC514) and m-xylene diamine (MXDA). The curing reactions, that is, epoxy-amine and cyclic carbonate aminolysis, monitored by ATR-IR spectroscopy at 50 °C are found to be concomitant yielding highly homogeneous materials. Hybrid networks are extensively characterized by swelling tests, TGA, DMA, DSC, tensile tests, rheology, and lap-shear-test on aluminum substrates. The introduction of hydroxyurethane moieties within the epoxy-amine networks enhanced the adhesion properties (up to 20% compare to neat epoxy resins) by combining hydrogen bonding capability and vitrimeric properties (thermoset able to flow). Rheological characterizations and reprocessing tests demonstrated that hybrid adhesives with up to 47 mol% of cyclic carbonate groups are capable of covalent exchange (internally catalyzed by tertiary amine) while keeping similar thermomechanical properties and enhanced adhesion strength compare to the permanent epoxy network.

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This study introduces an efficient strategy for synthesizing polyhydroxyurethane-based multicomponent hydrogels with enhanced rheological properties. In a single-step process, 3D materials composed of Polymer 1 (PHU) and Polymer 2 (PVA or gelatin) were produced. Polymer 1, a crosslinked polyhydroxyurethane (PHU), grew within a colloidal solution of Polymer 2, forming an interconnected network. The synthesis of Polymer 1 utilized a Non-Isocyanate Polyurethane (NIPU) methodology based on the aminolysis of bis(cyclic carbonate) (bisCC) monomers derived from 1-thioglycerol and 1,2-dithioglycerol (monomers A and E, respectively). This method, applied for the first time in Semi-Interpenetrating Network (SIPN) formation, demonstrated exceptional orthogonality since the functional groups in Polymer 2 do not interfere with Polymer 1 formation. Optimizing PHU formation involved a 20-trial methodology, identifying influential variables such as polymer concentration, temperature, solvent (an aprotic and a protic solvent), and the organo-catalyst used [a thiourea derivative (TU) and 1,8-diazabicyclo [5.4.0]undec-7-ene (DBU)]. The highest molecular weights were achieved under near-bulk polymerization conditions using TU-protic and DBU-aprotic as catalyst-solvent combinations. Monomer E-based PHU exhibited higher Mw¯ than monomer A-based PHU (34.1 kDa and 16.4 kDa, respectively). Applying the enhanced methodology to prepare 10 multicomponent hydrogels using PVA or gelatin as the polymer scaffold revealed superior rheological properties in PVA-based hydrogels, exhibiting solid-like gel behavior. Incorporating monomer E enhanced mechanical properties and elasticity (with loss tangent values of 0.09 and 0.14). SEM images unveiled distinct microstructures, including a sponge-like pattern in certain PVA-based hydrogels when monomer A was chosen, indicating the formation of highly superporous interpenetrated materials. In summary, this innovative approach presents a versatile methodology for obtaining advanced hydrogel-based systems with potential applications in various biomedical fields.

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Sandstone blocks quarried from the late Jurassic to the early Cretaceous Red Terrane Formation were used to construct the Wat Phu temple in Laos and the Banteay Chhmar temple in Cambodia. The sandstone blocks of the Banteay Chhmar temple are gray to yellowish brown in color and their magnetic susceptibilities and Sr contents are relatively high, similar to the sandstone blocks used in the Angkor monument. In contrast, the Wat Phu temple consists of reddish sandstone blocks with significantly lower magnetic susceptibilities and Sr contents than those used in the Banteay Chhmar temple and Angkor monument. The sandstone blocks of the Banteay Chhmar temple were likely supplied from quarries in Ta Phraya, Thailand, and those of the Wat Phu temple are likely to have been supplied from the area near these temples. The Red Terrane Formation is widely distributed throughout Mainland Indochina, and most of these sandstones show low magnetic susceptibilities and low Sr contents, similar to those of the Wat Phu temple. Sandstone with high magnetic susceptibilities and high Sr contents is found in the sandstone quarries in Ta Phraya and the southeastern foothill of Mt. Kulen, which is the supply source of the sandstone blocks used in the Angkor monument, early buildings of the Bakan monument, and Banteay Chhmar temple. The sandstone with high magnetic susceptibility and high Sr content is distributed in limited areas and implies a weak degree of weathering during the sandstone formation process or a difference in the source rocks.

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The Squaretail mullet Ellochelon vaigiensis is widely found from marine to brackish and freshwater, including the Vietnamese Mekong Delta (VMD). Data on the length-weight relationships (LWRs), growth pattern, and condition factor (CF) play an essential role in fisheries assessment but are limited to E. vaigiensis - a commercial fish in VMD. To better understand the growth pattern of this fish, the study collected samples at four sites, including Thanh Phu, Ben Tre (BT); Duyen Hai, Tra Vinh (TV); Tran De, Soc Trang (ST); and Dong Hai, Bac Lieu (BL). Each month, fish samples were collected using bottom nets at each sampling site during high tide in both the dry season (January to May 2021) and the wet season (November to December 2020 and June to October 2021). This study qualified whether LWRs, growth pattern, and CF of E. vaigiensis vary with sexual, intraspecific, and spatiotemporal variables. The analysis results of 942 specimens showed that fish total length (TL = 17.86 ± 0.13 cm) and weight (W = 54.29 ± 1.05 g) changed with sex, season, month and site. The W could be appraised from a given TL due to high coefficients (r 2 ) of LWRs that were regulated by fish size and season but not sex. The species showed negative allometry as its slope value of LWRs (b = 2.34 ± 0.30) was <3. The growth pattern did not change with sex and site but varied fish size, season, and months ranging from negative allometry to isometry. The CF of females (1.08 ± 0.01) was higher than males (0.99 ± 0.01). Albeit this fish showed spatiotemporal variation in CF, ranging from 0.81 ± 0.01 to 1.25 ± 0.02, the CF (1.02 ± 0.01) was significantly higher than the one threshold, indicating that E. vaigiensis lived a favorable condition. Research results show that this fish species has a dominant growth pattern in terms of length (b < 3) and is well adapted to the environment (CF ≈ 1). These data have an important role in suggesting the future aquaculture of this fish.

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Polyurethanes are one of the most important groups of polymers for numerous sectors of industry. Their production involves using dangerous components (diisocyanates), thus, in the search for safer synthetic routes, alternative methods yielding non-isocyanate polyurethanes (NIPU) have been investigated. In this study, the synthesis of polyhydroxyurethane from cyclic carbonates was performed. A three-factor, three-level Box-Behnken experimental design was constructed and the reaction time, temperature and reagents' molar ratio were the independent variables. The built model revealed that the viscosity was influenced by all three independent factors, while the mechanical properties and glass transition temperature of the PHUs were affected by the reagents' ratios. An experimental verification of the model proved its accuracy as the mechanical strength and glass transition temperature deviated from the modeled values, by 15% and 7%, respectively.

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Karst caves are oligotrophic environments that appear to support a high diversity of fungi. Studies of fungi in Thailand's caves are limited. During a 2019 exploration of the mycobiota associated with soil samples from a karst cave, namely, Phu Pha Phet in the Satun UNESCO Global Geopark in Satun Province, southern Thailand, two previously undescribed fungi belonging to Talaromyces (Trichocomaceae, Eurotiales, Eurotiomycetes) were studied using a polyphasic approach combining phenotypic and molecular data. Based on datasets of four loci (ITS, BenA, CaM, and RPB2), phylogenetic trees of the section Trachyspermi were constructed, and two new species-Talaromyces phuphaphetensis sp. nov. and T. satunensis sp. nov.-phylogenetically related to T. subericola, T. resinae, and T. brasiliensis, are described. Detailed descriptions and illustrations of the new species are provided. This study increases the number of cave-dwelling soil fungi discovered in Thailand's Satun UNESCO Global Geopark, which appears to be a unique environment with a high potential for discovering fungal species previously undescribed.

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The objective of this study was to identify the tenderness and energy metabolism attributes in normal ultimate pH (pHu, 5.4-5.8, NpHu), intermediate pHu (5.8-6.2, IpHu) and high pHu (> 6.2, HpHu) Longissimus lumborum from beef. During 21 days of aging, the IpHu group exhibited a higher Warner-Bratzler shear force, lower activity of µ-calpain, and a higher content of heat shock protein 27 and greater protein oxidation. Metabolomics analysis revealed that 24 differential metabolites were detected during the first 24 h postmortem between pH groups, and these were mainly the products of glycolysis, the tricarboxylic acid (TCA) cycle and oxidative phosphorylation. The relatively higher adenosine triphosphate content in the IpHu group could delay tenderization by being used as key substrate for protein phosphorylation. In addition, the relationship between guanosine triphosphate, diphosphate and monophosphate, and beef tenderness was worthy to be verified in the future study.

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Glycolytic potential (GP) is one of the postmortem traits used to predict the quality of the final meat products. Despite that, the knowledge of the molecular and metabolic pathways controlling this trait is still not complete. To add some information on this field we used two pools of Italian Large White heavy pigs divergent for GP to investigate through a microarray approach the differences of gene expressions between the two pools. On the whole, 32 genes were differentially expressed, and among them 31 were overexpressed in low GP pool. These genes were involved in mitochondrial functions and adenosine triphosphate (ATP) biosynthetic processes, in calcium homeostasis, and in lipid metabolism, with Peroxisome proliferator-activated receptor (PPAR) signaling being a possible master regulator of the molecular differences observed between the two pools. The different GP levels between the two pools could have determined in low GP muscles a more rapid occurrence of the molecular cascade related to the events triggering cell death.

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ETHNOPHARMACOLOGICAL RELEVANCE: Benign prostatic hyperplasia (BPH) is the hyperproliferation of the stromal and the epithelial cells within the prostatic transition zone. In recent years, phytotherapy have been studied with the concern for increasing quality of life, improving lower urinary tract symptoms (LUTS) as well as reducing prostate volume and the frequency of adverse events was similar to that of placebo. Linh Phu Khang Tue Tinh (LPKTT) capsules are formulated from 4 herbs widely used in traditional Vietnamese medicine - Panax notoginseng (Burkill) F.H.Chen - Tam that (radix), Crinum asiaticum L. - Náng hoa trang or giant crinum lily, Polygonum cuspidatum Willd. ex Spreng. (= Reynoutria japonica Houtt) - Cot cu khí or Japanese knotweed (radix), Oldenlandia herbacea (L.) Roxb. (formerly known as Hedyotis diffusa Spreng.) - Bach hoa xà thie^t thao or slender oldenlandia (herb). The preparation has been used in traditional Vietnamese medicine to treat nocturia, weak urine stream, urinary tract infection. According to modern studies, these herbs have anti-inflammation, antitumor, and antioxidant activities. AIMS OF THE STUDY: Evaluating the effects of LPKTT capsules on the development of BPH using a rat model of BPH induced by testosterone propionate (TP). MATERIALS AND METHODS: 60 male Wistar rats, 10-12 weeks of age, weight 200-250 g were separated into six groups: (G1) a normal control group that was taken orally phosphate-buffered saline (p.o.; PBS.) with corn oil (subcutaneous injection- Sc); (G2) a BPH model group that received PBS (p.o) with TP (Sc); (G3) a positive control group that received dutasteride (25 µg/kg BW/24 h, p.o.) with TP (Sc); (G4) a positive control group that received alfuzosin HCl (1.8 mg/kg BW/24 h, p.o.) with TP (s.c.) and (G5 and G6) LPKTT groups that received LPKTT at 289.8 or 869.4 mg/kg(p.o.) respectively, with TP (s.c.). BPH model was induced by Sc of TP, 3 mg/kg for 4 weeks. After that, rats were received NaCl/Dutasteride/Alfuzosin/LPKTT for the next 28 days. On the 56th day, assessed the results were through the indicators: micturition frequency, voided volume, total voided volume, the prostate and body weights, the ratio of prostate weight to body weight, prostate histology. RESULTS: LPKTT reduced micturition frequency and increased the voided volume when compared to the control group (p < 0.01). The results were equivalent to those of the alfuzosin ones (G4). LPKTT lowered prostate weight and the ratio of prostate weight to body weight when compared to the control group (p < 0.01). These reductions were the same in the dutasteride ones. Histomorphology in G5 and G6 also showed that LPKTT inhibited TP induced prostatic hyperplasia. The results were similar to that in the dutasteride group. Microscopic images of prostate in G5 and G6 were almost similar to that of G1. CONCLUSION: LPKTT capsules work to inhibit prostate proliferation in rats induced BPH by TP.

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A wide variety of factors prior to slaughter may affect the stress status of beef cattle, giving rise to well-known 'dark-cutting' defective meats characterised by a high ultimate pH (pHu). To understand the underlying mechanisms of pHu fluctuations in beef cattle there was studied the proteome changes caused by pre-slaughter stress through a gel-free proteomic approach. Comparative peptidomic analysis was carried out on 12 loin samples at 24 h post-mortem from Longissimus thoracis et lumborum bovine muscle of crossbred animals, previously sorted into two different groups according to their pHu values: normal (pHu < 6.0) and high (pHu ≥ 6.0). Tryptic peptides from direct protein extracts were approached by combining untargeted (intact mass, MS1) and targeted (Selected Reaction Monitoring, SRM) quantitative LC-MS assays followed by chemometric analysis. Seventeen peptide biomarkers belonging to 10 different proteins appropriately discriminated sample groups assayed. Results may promote the use of this simple and effective methodology towards the creation of new insights in meat quality research. SIGNIFICANCE: The significance of this study was the optimization of an affordable straightforward gel-free proteomic approach addressing the differentiation of the muscle sub-proteome of normal and high pHu meat samples. This strategy allowed the study of tryptic peptides from direct meat protein extracts by combining untargeted MS1 and targeted SRM quantitative assays performed by conventional LC-MS detection. Affordability, simplicity and robustness of this methodology can facilitate its readily implementation in routine protocols for quality assessment of meat.

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A new species of Limnonectes from Phu Yen Province, South-central Vietnam is described based on morphological and molecular differences. Morphologically, the new species is distinguishable from its congeners on the basis of a combination of the following diagnostic characters: SVL 49.8-77.9 mm in males, 40.8-61.8 mm in females; males with moderately enlarged head (HL/SVL 0.47, HW/SVL 0.48); head slightly broader than long (HL/HW 0.97 in males, 0.95 in females); vomerine teeth present; external vocal sacs absent; rostral length short (RL/SVL 0.15); tympanum invisible; dorsal surface of head, body and flanks with ridges and tubercles; dorsal surface of tibia and foot distinctly tuberculate, covered with moderately dense, small, low tubercles; supratympanic fold present; dorsolateral fold absent; Finger I with nuptial pad, composed of minute spines on dorsal surface and medial edge in males; toes webbed to distal of terminal phalanx, webbing formula I0-0II0-0III0-0IV0--0V0; in life, dorsum yellowish brown with dark brown markings; ventral surface white with brown markings. In phylogenetic analyses, the new species from Vietnam and Limnonectes fastigatus as well as L. kiziriani form a clade, which is sister to L. fragilis from China, although the nodal support values for the set of relationships are insignificant from all analyses.

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We describe a new species of Cyrtodactylus on the basis of four specimens collected from Phu My, Binh Dinh Province, southern Vietnam. Cyrtodactylus phumyensis sp. nov. is distinguished from the remaining Indochinese bent-toed geckos by a combination of the following characters: size small (SVL up to 66.8 mm); two internasals; dorsal tubercle rows 18 or 19 at midbody; ventral scale rows 33-41; ventrolateral folds slightly developed; each thigh with 5-7 enlarged femoral scales; femoral pores absent in males and female; a series of 5-7 precloacal pores plus a pitted, enlarged precloacal scale in males; 6 pitted, enlarged precloacal scales in female; paravertebral tubercles 20-23; lamellae under toe IV 18-21; small subcaudal scales, not transversely enlarged; two irregular dark longitudinal stripes on shoulder. In phylogenetic analyses, the new species is recovered as a member of the Cyrtodactylus irregularis species group, and strongly supported as a sister taxon of C. cucdongensis from Khanh Hoa Province.

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Argyreia pseudosolanum Traiperm & Suddee, sp. nov. from the NE region of Thailand is described and illustrated. The new species is remarkable in having a very distinctive corolla shape similar to Solanum, and staminal filament bases glabrous or nearly glabrous with a few multicellular, uniseriate hairs at the attachment point on the corolla tube. Detailed descriptions, illustrations, a summary of the ecology and an IUCN conservation status are provided.

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Pseudomonas aeruginosa exhibits a high requirement for iron, which it can acquire via several mechanisms, including the acquisition and utilization of heme. The P. aeruginosa genome encodes two heme uptake systems, the heme assimilation system (Has) and the Pseudomonas heme utilization (Phu) system. Extracellular heme is sensed via the Has system, which encodes an extracytoplasmic function (ECF) σ factor system. Previous studies have shown that the transfer of heme from the extracellular hemophore HasAp to the outer membrane receptor HasR is required for activation of the σ factor HasI and upregulation of has operon expression. Here, employing site-directed mutagenesis, allelic exchange, quantitative PCR analyses, immunoblotting, and 13C-heme uptake experiments, we delineated the differential contributions of the extracellular FRAP/PNPNL loop residue His-624 in HasR and of His-221 in its N-terminal plug domain required for heme capture to heme transport and signaling, respectively. Specifically, we show that substitution of the N-terminal plug His-221 disrupts both signaling and transport, leading to dysregulation of both the Has and Phu uptake systems. Our results are consistent with a model wherein heme release from HasAp to the N-terminal plug of HasR is required to initiate signaling, whereas His-624 is required for simultaneously closing off the heme transport channel from the extracellular medium and triggering heme transport. Our results provide critical insight into heme release, signaling, and transport in P. aeruginosa and suggest a functional link between the ECF σ factor and Phu heme uptake system.

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This article presents the raw data in relation to the status of, and the distribution of, the 41 marine algal species occurring around and within the An Thoi coral reef strictly protected zone, Phu Quoc Marine Protected Area. The data, which were collected in May 2017, include the detailed description of the locations, the oceanographical conditions, and the photographs of the 41 marine algal species. For more insight, please see "Marine algal species and marine protected area management: A case study in Phu Quoc, Kien Giang, Vietnam" Huynh and Nguyen, 2019.

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The biosynthesis of O antigenic polysaccharides in enteric bacteria from nucleoside diphosphate sugars (donor substrates) is catalyzed by the corresponding glycosyltransferases and proceeds through the intermediate formation of undecaprenyl diphosphate sugars (acceptor substrates). To study this process, a chemical synthesis of the compounds having the natural structure or their modified analogs is necessary. The phosphoroimidazolidate method is a universal method for synthesis of lipid diphosphate disaccharides containing 2-acetamido-2-deoxyglycosyl residue at the reducing end of the disaccharide moiety and 11-phenoxyundecyl residue as lipid fragment of the molecule. We report here protocols to synthesize the disaccharides P1-(11-phenoxyundecyl)-P2-(2-acetamido-2-deoxy-3-O-α-D-rhamnopyranosyl-α-D-glucopyranosyl) diphosphate [D-Rha(α1-3)-D-GlcNAcα-PP-PhU, Compound 1] and P1-(11-phenoxyundecyl)-P2-(2-acetamido-2-deoxy-3-O-ß-D-galactopyranosyl-α-D-galactopyranosyl) diphosphate [D-Gal(ß1-3)-D-GalNAcα-PP-PhU, Compound 6]. We describe the procedures for identification and structure estimation of compounds by TLC, NMR, and MS. We also include the biochemical testing of Compound 6 with α2,3-sialyltransferase WbwA from Escherichia coli O104.

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In this study we aimed to identify genomic regions associated with muscle pH, meat colour and water-holding capacity in a population of 280 Italian Duroc pigs genotyped by the Illumina PorcineSNP60 v2 Genotyping BeadChip. After quality control, the remaining 32 597 SNPs and 278 subjects were used to perform a genome-wide association study with the genabel package, using a kinship matrix in a model with the effects of sex, age and slaughter day. Bonferroni correction was applied, and the significant markers and regions were then further investigated to identify the nearest genes and the linkage disequilibrium (LD) between markers. Four markers (ASGA0082344, ASGA0095635, DBWU0000985 and CASI0005117) were significantly associated with ultimate pH (pHu ); no significant association was detected for the other traits. The four significant variants, located from 16.841 to 17.643 Mb on chromosome 3, were found within or close to the sequences of the sulfatase modifying factor 2 (SUMF2), lysine acetyltransferase 8 (KAT8), serine protease 8 (PRSS8) and phosphorylase kinase catalytic subunit gamma 2 (PHKG2) genes. The four associated markers lie in two LD blocks, suggesting that the observed effect is related to mutations located in two regions: the first one where SUMF2 is mapped and the second one where genes KAT8, PRSS8 and PHKG2 are located.

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The present study reports three new species of Ostracoda, Loxoconcha damensis sp. nov., Xestoleberis vietnamensis sp. nov. and X. munensis sp. nov., from Phu Quoc Island, southwest Vietnam and Nha Trang Bay, central Vietnam. These species inhabit the coral reefs around isolated islands and can be easily distinguished from other known species based on their morphological differences, mainly in the male copulatory organ. Loxoconcha damensis sp. nov. belongs to Loxoconcha Group A, based on the distributional pattern of their pore system below the eye tubercle. Similarly, based on a combination of morphological types of pore systems, the two new Xestoleberis species belong to Xestoleberis Group A, because these species have two types of pore systems, i.e., sieve-type and lip-type. To the best of our knowledge, this study is the first report on Xestoleberididae and the second on Loxoconchidae from the Recent of Vietnam.

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We describe a new species of megophryid frog from Phu Yen Province in southern Vietnam. Leptolalax macrops sp. nov. is distinguished from its congeners by a combination of the following morphological attributes: (1) body size medium (SVL 28.0-29.3 mm in three adult males, 30.3 mm in single adult female); (2) supra-axillary glands present, creamy white; ventrolateral glands indistinct; (3) tympanum externally distinct; (4) dorsal skin roughly granular with larger tubercles, dermal ridges on dorsum absent; (5) rudimentary webbing present between fingers I-II and II-III; rudimentary webbing between all toes; fingers and toes without dermal fringes; (6) in life ventral surface greyish-violet with white speckling; (7) supratympanic fold distinct, dark brown in life; (8) iris bicolored, typically golden in upper half, fading to golden green in lower half; (9) tibia short (TbL/SVL 0.44-0.45 in males); and (10) eyes large and protuberant (ED/SVL 0.15-0.16 in males). From all congeners for which comparable sequences are available, the new species differs markedly in the 16S rRNA mitochondrial gene sequence (P-distance>5.7%). The new species is currently known only from montane evergreen tropical forests of Song Hinh District, Phu Yen Province, and M'Drak District of Dak Lak Province at elevations of 470-630 m a.s.l. We suggest the new species should be considered as Data Deficient following the IUCN's Red List categories. We also report a previously unknown Leptolalax mtDNA lineage from an evergreen tropical forest in the Hoa Thinh District of Phu Yen Province, which may also represent an undescribed species.

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Two new penicillate millipede species from the genera Unixenus and Monographis (Diplopoda, Polyxenidae) were collected from Phu Quoc Island, Vietnam's largest island. Unixenus intragramineus sp. n. was found within the stem of a creeping grass growing on an unstable, sandy substrate in the intertidal zone. The defining taxonomic characteristics of the genus Unixenus were apparent in U. intragramineus sp. n., but it is distinctively different from all described species. Monographis phuquocensis sp. n. belongs to a group of Monographis species which have their antennal sensilla arranged in a crescent-shape; but the structure of the labrum and telotarsus observed in this new species differs from other described Monographis.

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