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Enhanced efficacy in species delimitation is critically important in biology given the pending biodiversity crisis under global warming and anthropogenic activity. In particular, delineation of traditional classifications in view of the complexity of species requires an integrative approach to effectively define species boundaries, and this is a major focus of systematic biology. Here, we explored species delimitation of Engelhardia in tropical and subtropical Asia. In total, 716 individuals in 71 populations were genotyped using five chloroplast regions, one nuclear DNA region (nrITS), and 11 nuclear simple sequence repeats (nSSR). Phylogenetic trees were constructed and relationships among species were assessed. Molecular analyses were then combined with 14 morphological characteristics of 720 specimens to further explore the species boundaries of Engelhardia. Integrating phylogenetic and morphological clusters provided well-resolved relationships to delineate seven species. The results suggested that: first, that E. fenzelii, E. roxburghiana, E. hainanensis, E. apoensis, and E. serrata are distinct species; second, E. spicata var. spicata, E. spicata var. aceriflora, E. spicata var. colebrookeana, and E. rigida should be combined under E. spicata and treated as a species complex; third, E. serrata var. cambodica should be raised to species level and named E. villosa. We illuminated that bias thresholds determining the cluster number for delimiting species boundaries were substantially reduced when morphological data were incorporated. Our results urge caution when using the concepts of subspecies and varieties in order to prevent confusion, particularly with respect to species delimitation for tropical and subtropical species. In some cases, re-ranking or combining subspecies and/or varieties may enable more accurate species delimitation.

In this paper, the influence of salt fog and ambient condition exposure on CFRP-to-steel bonded joints (CSJs) with a near end mechanical anchorage was studied. The tests of the CSJs were carried out with a monotonic loading history respectively with and without a near end mechanical anchorage both unaged and after being exposed to the ageing conditions. The results revealed failures in the adhesive for some CSJs with a near end mechanical anchorage, among which also exhibited the best bond performance both in aged and unaged specimens. Due to the high state of degradation after ageing exposure, local damage of the CFRP located at the gap position of the CSJs was induced by a torsion action during the fixation of the specimen in the tensile machine even prior to the testing, which caused, although locally, severe delamination of the CFRP of the aged CSJs. From the torsion test results, a decrease in the torsional capacity of the CFRP after aging revealed the degradation of the carbon fiber-to-matrix interface. Additional results reflected that a drop in the initial stiffness of the load vs. slip relationship can be observed, caused by a pre-crack with a length of 30 mm in the CSJs.

Background Dai, Hani, and Yao people, in the trans-boundary region between China, Laos, and Vietnam, have gathered plentiful traditional knowledge about wild edible plants during their long history of understanding and using natural resources. The ecologically rich environment and the multi-ethnic integration provide a valuable foundation and driving force for high biodiversity and cultural diversity in this region. However, little study has uncovered this unique and attractive culture to the world. Methods We conducted ethnobotanical survey in 20 villages of Jiangcheng County from 2016 to 2020. Altogether 109 local Dai, Hani, and Yao people were interviewed, and their traditional knowledge about wild edible plants was recorded. Voucher specimens were identified by the authors and deposited in the herbarium of Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences (HITBC). The use value was used as a quantitative index to evaluate the consumption frequency and relative importance of the wild edible plants. The Jaccard index was calculated to assess the usage similarity of different areas. The relationship of age and recognized wild edible plants by different ethnic people was performed by R. Results A total of 211 wild edible plants, belonging to 71 families and 151 genera, were recorded. These plants were consumed as wild edible vegetables, seasonal fruits, salads, spices, sour condiments, tonic soups, tea substitutes, liquor brewing, or dyeing materials. The use value (UV), current cultivation, market availability, and the quantitative traditional knowledge inheritance situation of these wild edible plants among different generations, were analyzed. Based on the data from the threatened species list of China’s higher plants and the IUCN Red List, the food plant list for Asia Elephant, the Subject Database of China Plant, and the calculated UV score, the top 30 most important wild edible plants were selected for further cultivation in some local villages. Conclusion Traditional knowledge of wild edible plants, owned by Dai, Hani, and Yao people in Jiangcheng County, is rich but at risk of being lost among the young generation. Diversified cultivation of wild edible plants by the local communities could be a solution for the sustainable use of natural resources and to conserve the endangered species in this trans-boundary region.

Zingiber natmataungense S.S.Zhou & R.Li (Zingiberaceae), a new species from Natma Taung National Park, Chin State, Myanmar, is described and illustrated. The new species is morphologically similar to Z. yunnanense, but differs by: leaf blade abaxially light green, glabrous, ligule sparsely pubescent, ca. 2–3 mm, bracts glabrous; calyx white 20–21 × 3.2–3.5 mm, glabrous, apex obviously 3-toothed; corolla tube white, ca. 3.9–4.1 cm, labellum lateral lobes, ca. 1.5–1.7 × 0.6–0.7 cm; stamen with sparse pubescent, filament white, glabrous,1–2 mm; anther connective appendage yellowish proximally, purplish distally; ovary white, sparsely white pubescent, epigynous glands, ca. 6–7 mm long, tapered, apex whorled, yellow. This new species is also similar to Z. teres, but has a different flower colour.

Fibre-reinforced polymer (FRP)-confined concrete-encased steel columns (FCSCs) have emerged as a new form of hybrid columns. An FCSC consists of an outer FRP tube, an inner steel section, and concrete filled in between. The concept of FCSCs not only provides a durable and ductile structural form for new construction, but also can be practiced as an effective method for the retrofitting/strengthening of existing steel columns. This paper presents the first ever study on FCSCs with a large rupture strain (LRS) FRP tube [i.e., polyethylene terephthalate (PET) FRP tube]. A total of 12 circular specimens (six FCSCs and six FRP-confined concrete columns) were tested, with the main test variable being the thickness of the PET FRP tube. The test results showed that the buckling of the encased steel section can be well prevented by the constraint from the surrounding FRP-confined concrete even when the axial deformation is large. On the other hand, the encased steel section can provide additional confinement to the concrete in FCSCs, leading to excellent structural performance of the columns in terms of both axial strength and deformation capacity.

Enhanced efficacy in species delimitation is critically important in biology given the pending biodiversity crisis under global warming and anthropogenic activity. In particular, delineation of traditional classifications in view of the complexity of species requires an integrative approach to effectively define species boundaries, and this is a major focus of systematic biology. Here, we explored species delimitation of Engelhardia in tropical and subtropical Asia. In total, 716 individuals in 71 populations were genotyped using five chloroplast regions, one nuclear DNA region (nrITS), and 11 nuclear simple sequence repeats (nSSR). Phylogenetic trees were constructed and relationships among species were assessed. Molecular analyses were then combined with 14 morphological characteristics of 720 specimens to further explore the species boundaries of Engelhardia. Integrating phylogenetic and morphological clusters provided well-resolved relationships to delineate seven species. The results suggested that: first, that E. fenzelii, E. roxburghiana, E. hainanensis, E. apoensis, and E. serrata are distinct species; second, E. spicata var. spicata, E. spicata var. aceriflora, E. spicata var. colebrookeana, and E. rigida should be combined under E. spicata and treated as a species complex; third, E. serrata var. cambodica should be raised to species level and named E. villosa. We illuminated that bias thresholds determining the cluster number for delimiting species boundaries were substantially reduced when morphological data were incorporated. Our results urge caution when using the concepts of subspecies and varieties in order to prevent confusion, particularly with respect to species delimitation for tropical and subtropical species. In some cases, re-ranking or combining subspecies and/or varieties may enable more accurate species delimitation.

Ovarian cancer is one of the most common malignancies in women and characterized by a rapid progression to metastasis, which restricts effective treatment options. Caffeic acid phenethyl ester (CAPE), a natural honeybee product, exhibits a variety of biological activities, anti-tumor is included. Our study aims to explore whether CAPE could inhibit the progression of ovarian cancer and the underlying molecular mechanism. The establishment of ovarian cancer model was set up in mice through caudal vein injection of SKOV-3 cells. Results indicated that CAPE treatment remarkably decreased the viability, migration and invasion of SKOV-3 cells. Besides that, the apoptosis of SKOV-3 cells was significantly promoted by CAPE treatment. Moreover, the growth of ovarian cancer was tremendously inhibited by CAPE in vivo and its action was accompanied by the obstructed Ki67 and PCNA expression. Furthermore, nuclear factor kappa b (NF-?B) pathway was dramatically suppressed by CAPE through the inhibition of I?B phosphorylation, nuclear translocation of p65 and NF-?B p65 DNA binding activity. By contrast, cells transfected with p65 siRNA exhibited decreased cell viability, migration and invasion along with increased cell apoptosis in SKOV-3 cells. However, CAPE treatment could enhance these alters induced by p65 siRNA in KOV-3 cells. Taken together, these findings suggested that CAPE could restrain the progression of ovarian cancer via inactivating NF-?B signaling, and may provide novel therapeutic regimens for ovarian cancer.

The strong column-weak beam hierarchy, which is now widely accepted in the design of reinforced concrete (RC) frames to achieve good seismic performance , is violated in many existing RC frames designed according to inadequate design codes (generally previous codes). Against this background, a novel seismic retrofit method based on the flexural weakening-shear strengthening (FWSS) technique was proposed by the authors’ group to achieve the strong column-weak beam hierarchy in such frames. This technique involves the creation of an opening in the web of a T-section beam (or an alternative feature with a similar effect) for a reduction in the flexural capacity of the beam and the use of local FRP strengthening to avoid shear failure of the post-weakening beam to ensure a ductile failure process. To confirm/demonstrate the effectiveness of the FWSS technique, an experimental study consisting of a total of 8 full-scale RC beams was carried out. Test results presented in this paper show that a sizable web opening can effectively reduce the flexural capacity of a T-section beam and the FRP strengthening system is needed to avoid shear failure of the beam and confine the web chord created by the opening to ensure a ductile response.

Dendrobium naungmungense, a new species from Naungmung, Kachin State, North Myanmar, is described and illustrated. It is morphologically similar to D. ciliatilabellum and D. vexabile, but the epichile is oblong with three long-ciliate laminae and the column wing has significant denticulation. A preliminary risk-of-extinction assessment shows that the new species should be regarded as Critically Endangered (CR) according to the IUCN Red List Categories and Criteria.

Hedychium putaoense Y.H. Tan & H.B. Ding, a new species of Zingiberaceae from Putao, Kachin state, Northern Myanmar, is described and illustrated. It is similar to H. densiflorum Wall. and H. longipedunculatum A.R.K. Sastry & D.M. Verma, but differs by its very small bract (4–6 × 2.5–3 mm vs. 18–19 × 5–5.5 mm and ca. 11 × 7 mm, respectively), semicircle and dark red bracteole, orange flower and broadly falcate to lanceolate lateral staminodes.

Aristolochia sinoburmanica Y.H.Tan & B.Yang, a new species of Aristolochiaceae from Putao, Kachin State, Myanmar, is described and illustrated. According to morphology (strongly curved perianth, 3-lobed limb, as well as 3-lobed gynostemium, anthers 6, adnate in 3 pairs to the base of gynostemium, opposite to the lobes), the species belongs to Aristolochia subgenus Siphisia. It is morphologically similar to A. faviogonzalezii, A. hainanensis, A. tonkinensis, A. saccata and A. xuanlienensis. The major differences between them are outlined and discussed. A detailed description, along with line drawings, photographs, habitat, distribution and conservation status, as well as a comparison to morphologically similar species, are also provided.

The effects of seawater and undesalted sea sand on the early-age hydration, mechanical performance, water absorption, leaching behavior and hydration products of Portland cement mortars with only sea sand, seawater, or both seawater and sea sand were fundamentally investigated in this study. The results show that the salts content in sea sand could accelerate the hydration reaction and increase the early-stage compressive strength, while the physical properties of sea sand have an adverse effect on the strength development, leading to the compressive strength of cement mortar with only sea sand lower than the ones with demineralized water and river sand. The addition of seawater could significantly accelerate the hydration due to its high salts content, which could compensate for the side effect of sea sand and make the cement mortar with seawater and sea sand with the highest compressive strength. The chloride, sulphate and magnesium ions in seawater and/or sea sand may lead to the phase changes of cement mortars. The chloride and sulphate ions in seawater and sea sand reacted with tricalcium aluminate (C3A) and the hydrated product of Portlandite to form much more Friedel’s/Kuzel’s salts and ettringite. Moreover, the magnesium ions primarily in seawater generated magnesium hydroxide (Mg(OH)2) and magnesium silicate hydrate (M−S−H) formation by replacing the Ca2+ and decalcification of calcium silicate hydrate (C-S-H). The substitute of seawater also can make the Si/Ca ratio of the C-S-H (Cl) be increased from the range of 0.2–0.4 to 0.6–1.2 respectively. Therefore, utilization of seawater and undesalted sea sand in concrete production provides a sustainable way to solve the shortage of natural freshwater and river sand.

The near-surface mounted (NSM) FRP strengthening technique has attracted worldwide attention as an effective alternative to the externally bonded (EB) FRP strengthening technique. In the NSM FRP strengthening method, grooves are first cut in the concrete cover of a concrete member for the FRP reinforcement to be inserted and embedded using an adhesive. The NSM FRP method has many advantages over the EB FRP method, including a higher bonding efficiency and a better protection of the FRP reinforcement. Existing experimental studies have shown that FRP strips owned a better bond efficiency compared with other section shapes (e.g. round bars and square bars), due to the fact that they had a larger perimeter-to-cross-sectional area ratio. This paper presents a state-of-the-art review, particularly on the flexural strengthening of RC beams with NSM CFRP strips. The observed failure modes in laboratory experiments of such FRP-strengthened RC beams are classified and the existing strength models are examined along with the failure mechanisms behind. The main knowledge gaps to be bridged in future studies are also identified. This review partially formed the basis of the development of design provisions on the NSM strengthening technique in the relevant Hong Kong design guideline.

FRP-confined concrete-encased cross-shaped steel columns (FCCSCs) are a new form of hybrid columns recently developed at the University of Wollongong. An FCCSC consists of a square FRP outer tube, a cross-shaped steel section and concrete filled in between. This sectional configuration ensures that the concrete is very effectively confined despite the square shape of the column. In addition, the cross-shaped steel section serves as the ductile longitudinal reinforcement for loads in the two lateral directions and its possible buckling is constrained by the FRP outer tube and the concrete, leading to a column that is highly ductile. In this paper, results from a series of stub column tests are presented to demonstrate the concept of the new column form. The experimental program involved the testing of FCCSC specimens as well as four types of similar column forms, namely, square FRP-confined plain concrete columns (SFCPCs), circular FRP-confined plain concrete columns (CFCPCs), concrete-encased cross-shaped steel columns and square plain concrete columns. The test results confirmed the excellent performance of FCCSCs. The test results also showed that compared with the concrete in SFCPCs and that in CFCPCs, the concrete in FCCSCs has a much larger ultimate axial strain and a larger compressive strength, when the same FRP tube is used.

In the strengthening of existing deficient structures using the near-surface mounted (NSM) FRP method, a group of parallel NSM FRP strips are usually needed to meet the capacity enhancement requirement. When the groove spacing (i.e., the net distance between grooves) is relatively small, the bond behaviour of each NSM FRP strip is detrimentally influenced by the adjacent grooves/FRP strips, and such detrimental effect should be taken into account for a safe design of the NSM FRP strengthening system. All the existing models, however, have been proposed for NSM bonded joints with a single FRP strip and thus cannot consider the effect of groove spacing on the bond behaviour, due to the insufficiency of data from tests or numerical simulations. Against this background, a numerical parametric study, was conducted to clarify the effect of groove spacing on the bond strength of such bonded joints; the numerical parametric study involved the use of a three-dimensional meso-scale finite element model developed in the present study for NSM bonded joints with two FPP strips separately embedded in two parallel grooves. Based on the results from the parametric study, a reduction factor to account for the detrimental effect of insufficient groove spacing on the bond strength is proposed and extended to NSM bonded joints with three or more evenly-spaced FRP strips. By combining the proposed reduction factor and the bond strength model previously developed by the authors for NSM bonded joints with a single FRP strip, a bond strength model for NSM bonded joints with multiple FRP strips is proposed and the accuracy of the proposed model is verified with test results.

Fibre-reinforced polymer–concrete–steel hybrid multi-tube concrete columns are a new form of columns recently proposed at the University of Wollongong. An multi-tube concrete column consists of an external fibre-reinforced polymer tube and a number of circular internal steel tubes, with the space inside all the tubes filled with concrete. This article presents the first ever experimental study on square multi-tube concrete columns. The experimental program included a total of 14 stub column specimens tested under axial compression, with the test variables being the thickness of the external fibre-reinforced polymer tube, and the dimensions and configuration of the internal steel tubes. The test results demonstrated that the concrete in the square multi-tube concrete columns was very effectively confined by the multiple tubes, and that the buckling of the internal steel tubes was completely prevented, leading to full structural utilization of the materials and a very ductile response. The test results also showed that the behaviour of the concrete in the square multi-tube concrete columns was significantly superior to that in the corresponding square concrete-filled fibre-reinforced polymer tubes, in terms of the compressive strength, the ultimate axial strain and the stiffness of the second branch of the stress–strain curve. A simple analytical model proposed for the axial load-axial strain curve of square multi-tube concrete columns is also presented and is shown to provide reasonable and conservative predictions of the test results.

Coelogyne magnifica (Orchidaceae), a new species from Putao, Kachin State, Myanmar, is described and illustrated. It belongs to Coelogyne section Ocellatae Pfitzer & Kraenzl. and it is morphologically similar to Coelogyne corymbosa and C. taronensis, but can be distinguished from these species by its larger flowers, lanceolate sepals and petals, a narrowly ovate lip, which has two bright yellow patches surrounded by shiny brownish red and two fimbriate or erose-lacerate lateral keels on the lip. The major differences between these species are outlined and discussed.

FRP-confined concrete-encased cross-shaped steel columns (FCCSCs) are an emerging form of hybrid columns, consisting of a square FRP outer tube, a cross-shaped steel section and a concrete infill. The steel section in FCCSCs serves as ductile longitudinal reinforcement, and its buckling is well constrained by the concrete and the FRP tube. In addition, the steel section provides confinement to the concrete together with the FRP tube, so that the concrete in FCCSCs is effectively confined despite their square cross section. This paper presents a systematic experimental study on FCCSCs. The test variables included the flange width, flange thickness and web thickness of the steel section, and the thickness of FRP tube. It is shown that the various steel sections in the tested FCCSCs all provided substantial confinement to the concrete, while the effect of the steel confinement is less pronounced for FCCSCs with a thicker FRP tube. The test results show that the variation of the cross-sectional dimensions of the steel section, within a reasonably wide practical range, has marginal effects on the behaviour of the concrete in FCCSCs. In addition, a simple method has been proposed to predict the axial load capacity and ultimate axial strain of FCCSCs.

In order to realize the strong column-weak beam hierarchy in existing reinforced concrete (RC) frames, a novel seismic retrofit technique (i.e., beam opening technique or BO technique) was proposed. The BO technique involves the cutting of a web opening in the RC T-section beam to weaken its flexural capacity , in combination with the installation of a fibre-reinforced polymer (FRP) strengthening system around the opening to offset the loss in shear capacity caused by the opening. While extensive experimental studies have verified the effectiveness of the BO technique, this paper presents a finite element (FE) study on the structural behaviour of RC beams with an FRP-strengthened web opening, for a more comprehensive and in-depth understanding of the performance of such beams. Two constitutive models of concrete were investigated, namely, the concrete damaged plasticity (DP) model and the brittle cracking (BC) model. Through detailed comparisons, it was found that for specimens failing in a flexural mode, the DP model is more appropriate; while for specimens failing in a shear mode, the BC model with the secant modulus of concrete adopted provides better predictions. A simple method for the selection of a proper FE approach is finally proposed.

Mechanical anchorage devices have the potential to efficiently improve the bond behavior of Carbon Fiber-Reinforced Polymers (CFRP) Externally Bonded (EB) onto steel with an adhesive. Existing relevant studies, however, have been very limited. Against this background, experimental and numerical studies on the double overlapped CFRP-to-steel bonded joints with an end mechanical anchorage were carried out in the present study. Two types of CFRP laminates (i.e. , SIKA CFRP and the other type made in Harbin Institute of Technology – HIT) were used in the bond tests, with or without end mechanical anchorage devices. The test results showed that the end mechanical anchorage had marginal effect on the bond-slip relationship between EB CFRP and steel as well as debonding load, but could increase the ultimate load. It was also found that CFRP laminate from HIT had a better bond performance than that from SIKA, in terms of both debonding load and ultimate load. Using ABAQUS, Finite Element (FE) model was established on such bonded joints and the accuracy was verified with test results. The verified FE model was adopted in a parametric study to further clarify the effect of key parameters on the bond behavior of such bonded joints.