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Abstract Objective The purpose of this study was to investigate the long-term consequences on the cervical spine after Anterior transcorporeal percutaneous endoscopy cervical discectomy (ATc-PECD) from the biomechanical standpoint. Methods A three-dimensional model of the normal cervical spine C2-T1 was established using finite element method. Subsequently, a disc degeneration model and degeneration with surgery model were constructed on the basis of the normal model. The same loading conditions were applied to simulate flexion, extension, lateral bending and axial rotation of the cervical spine. We calculated the cervical range of motion (ROM), intradiscal pressure, and intravertebral body pressure under different motions for observing changes in cervical spine biomechanics after surgery. At the same time, we combined the results of a long-term follow-up of the ATc-PECD, and used imaging methods to measure vertebral and disc height and cervical mobility, the Japanese Orthopaedic Association (JOA) score and visual analog scale (VAS) score were used to assess pain relief and neurological functional recovery. Results The long-term follow-up results revealed that preoperative JOA score, neck VAS score, hand VAS score, IDH, VBH, and ROM for patients were 9.49 ± 2.16, 6.34 ± 1.68, 5.14 ± 1.48, 5.95 ± 0.22 mm, 15.41 ± 1.68 mm, and 52.46 ± 9.36° respectively. It changed to 15.71 ± 1.13 (P

Abstract Although it is well documented that mountains tend to exhibit high biodiversity, how geological processes affect the assemblage of montane floras is a matter of ongoing research. Here, we explore landform-specific differences among montane floras based on a dataset comprising 17,576 angiosperm species representing 140 Chinese mountain floras, which we define as the collection of all angiosperm species growing on a specific mountain. Our results show that igneous bedrock (granitic and karst-granitic landforms) is correlated with higher species richness and phylogenetic overdispersion, while the opposite is true for sedimentary bedrock (karst, Danxia, and desert landforms), which is correlated with phylogenetic clustering. Furthermore, we show that landform type was the primary determinant of the assembly of evolutionarily older species within floras, while climate was a greater determinant for younger species. Our study indicates that landform type not only affects montane species richness, but also contributes to the composition of montane floras. To explain the assembly and differentiation of mountain floras, we propose the ‘floristic geo-lithology hypothesis’, which highlights the role of bedrock and landform processes in montane floristic assembly and provides insights for future research on speciation, migration, and biodiversity in montane regions.

A new spleenwort species, Asplenium guodanum, was found and described from Danxia landform region in Guangdong, China. The new species has close resemblance to A. subcrenatum Ching ex S.H.Wu in morphology, but can be distinguished by having plants small, stipes and rachises not covered with fibrous scales, relatively fewer pairs of pinnae, pinnae short, pinna margin weakly biserrate, pinna apex acute and lower pinnae obviously reduced. Phylogenetic analyses, based on six plastid markers (atpB, rbcL, rps4 & rps4-trnS and trnL & trnL-F) of the new species and its relatives, support a close relationship between A. guodanum and A. subcrenatum. Only one population with no more than 50 individuals were found and, therefore, it is recommended to be classified as Critically Endangered (CR) following IUCN Red List Criteria.

Abstract Objective Full endoscopic techniques are being gradually introduced from single-segment cervical disc herniation surgery to two-segment cervical disc herniation surgery. However, there is no suitable full endoscopic treatment for mixed-type two-segment cervical disc herniation (MTCDH) in which one segment herniates in front of the spinal cord and the other segment herniates behind the spinal cord. Therefore, we introduce a new full endoscopic technique by combining an anterior transcorporeal approach and a posterior translaminar approach. In addition, we provide a brief description of its safety, efficacy, feasibility, and surgical points. Methods Thirty patients with MTCDH were given full endoscopic surgical treatment by a combined transcorporeal and transforaminal approach and were followed up for at least 12 months. Results Clinical assessment scales showed that the patient’s symptoms and pain were significantly reduced postoperatively. Imaging results showed bony repair of the surgically induced bone defect and the cervical Cobb angle was increased. No serious complications occurred. Conclusion This technique enables minimally invasive surgery to relieve the compression of the spinal cord by MTCDH. It avoids the fusion of the vertebral body for internal fixation, preserves the vertebral motion segments, avoids medical destruction of the cervical disc to the greatest extent possible, and expands the scope of adaptation of full endoscopic technology in cervical surgery.

A new species of the genus Camellia (Theaceae), Camellia zijinica, discovered in the Danxia landscape from Guangdong Province, China, is characterized and illustrated. Phylogenetic analysis based on chloroplast genomes suggested its affinity with C. drupifera, C. oleifera and C. fluviatilis, however, it morphologically differs from all of the latter by leaf shape and size. Phonologically, it most closely resembles C. microphylla, but can be distinguished from the latter by its young branchlets glabrous (vs. densely pubescent), fewer bracteoles and sepals, diverse leaf shape, midvein raised slightly with sparsely pubescent or glabrous (vs. prominently with densely pubescent) and leaf adaxially matt (vs. vernicose) when dried. By morphological and molecular analyses, Camellia zijinica represented a distinct new species of C. sect. Paracamellia.

Lysimachia danxiashanensis, a new Primulaceae species, endemic to the Danxia landscape in Guangdong Province, China, is described and illustrated. This new species is morphologically similar to L. pseudohenryi, L. phyllocephala, L. congestiflora and L. kwangtungensis, but it differs from the similar species by its purplish-red plants, petiole without wings, calyx with orange glandular and the corolla margin serrated on upper half with orange-red glandular punctates. This new species belongs to Lysimachia subgen. Lysimachia sect. Nummularia. Phylogenetic analysis confirmed that L. danxiashanensis is a distinct clade, based on the combined data of ITS and rbcL sequences. The conservation status of the new species was evaluated as Endangered (EN) according to IUCN Red List Categories and Criteria.

Abstract Background The current treatments for adjacent two-segment cervical spondylotic myelopathy (CSM) include two-segment anterior cervical discectomy and fusion (ACDF) and single-segment anterior cervical corpectomy and fusion (ACCF). Long-term follow-up has demonstrated that both procedures have complications such as reduced cervical mobility, accelerated degeneration of adjacent segments and loosening of internal fixation screws. The purpose of this study is to demonstrate the feasibility, safety, and efficacy of anterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord (APFETDSC) via one vertebra with two bony channels for the treatment of adjacent two-segment CSM and to present our surgical experience. Methods Anterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord (APFETDSC) via one vertebra with two bony channels was performed for 12 patients with adjacent two-segment CSM with follow-up care for at least 12 months. The Visual analog scale (VAS) and the Japanese Orthopedic Association Score (JOA) were recorded, and modified Macnab criteria were used to evaluate the treatment excellence rate. Radiological examinations, including X-ray, computed tomography (CT) and magnetic resonance imaging (MRI), were used to evaluate spinal cord decompression, intervertebral stability and healing of the bony channel. Results All 12 patients completed the operation successfully. No postoperative complications, such as dysphagia, Horner’s syndrome, or laryngeal recurrent nerve palsy, were found. The postoperative VAS and JOA scores were significantly improved compared with those before surgery(P

Abstract Background Evaluate the effectiveness of posterior percutaneous full-endoscopic technique for patients with thoracic myelopathy caused by ossification of ligamentum flavum (TOLF). Methods A prospective study was conducted for 16 patients with TOLF, who were treated with posterior endoscopic technique from 2017 to 2019. The sagittal and cross-sectional CT images are used to measure the area of ossified ligamentum and evaluate the decompression of surgery, respectively. The effectiveness was evaluated with visual analog scale (VAS), modified Japanese Orthopedic Association scale (mJOA), The Oswestry Disability Index (ODI), and Macnab efficacy evaluation. Results The average area of TOLF on sagittal and cross-sectional CT images in the 16 patients was (116.62 ± 32.72) mm2 and (141.59 ± 27.25) mm2 preoperatively, (15.99 ± 12.54) mm2 and (11.72 ± 8.64) mm2 at 3 days after the operation, (16.78 ± 11.49) mm2 and (10.82 ± 7.57) mm2 postoperative 1 year, respectively. The invasive proportion of spinal canal at preoperative sagittal and cross-sectional CT images was (48.10 ± 10.04) % and (57.58 ± 11.37) %, which decreased to (6.83 ± 4.48) % and (4.40 ± 3.01) % at the final follow-up. The average score of mJOA, VAS and ODI improved. The excellent and good rate was 87.50% according to Macnab evaluation. Compared with preoperative, differences in areas of TOLF, proportions of spinal canal, and clinical assessments of postoperative 3 days and 1 year were all statistically significant. Two cases of dural tear were observed. Conclusion Endoscopic surgery has a good clinical effect on TOLF, which has the advantage of less trauma to the paraspinal muscles and no impact on the spinal structure. The CT-based radiographic measurements can quantitatively evaluate the degree of spinal canal stenosis in TOLF.

Commelina danxiaensis (Commelinaceae), a remarkable new species from Mount Danxia, Guangdong Province, China, is described and illustrated. This species is similar to C. communis in inflorescences and flowers but readily distinguishable in its nearly erect stems, larger flowers, and different petal colouration.

Argostemma ehuangzhangense, a new Rubiaceae species from E’huangzhang Nature Reserve, Guangdong Province, China, is here described and illustrated. A morphological comparison between the new species and its putative relatives, A. lamxayanum, A. laotica and A. verticillatum, is presented. The new species is mostly similar to A. laotica, but they can be distinguished from each other since Argostemma ehuangzhangense presents solitary flower (vs. 2-flowered inflorescences), flower lobes 4 (vs. 5) and anthers opening by longitudinal slits (vs. apical pores). In a preliminary IUCN Red List status of Argostemma ehuangzhangense this species is assigned as Vulnerable (VU).

The new species Eriobotrya crassifolia, collected from Yunnan Province, China, is characterised and illustrated. A phylogeny based on chloroplast genomes supported its closest affinity with E. tengyuehensis, while a phylogeny based on 197 single-copy nuclear genes supported its closest affinity with E. fragrans and E. deflexa. Morphologically, however, it resembles E. angustissima. Nevertheless, it can be easily distinguished from E. angustissima by its abaxially retroflexed and sharply serrate leaf margins, densely rusty tomentose inflorescences, and oblong or elliptic leaves.

A new species, Wikstroemia fragrans (Thymelaeaceae, Daphneae), from Danxiashan National Park, Shaoguan, Guangdong of China is described and illustrated. It is similar to the sympatric W. trichotoma, but can be differentiated easily from the latter by its shorter racemose inflorescences, yellowish green calyx tube, and smaller leaves. It also resembles the allopatric W. fargesii, but differs from it by its strigose-pubescent ovary and disk scale that is 2- or 3-dentate apically. Phylogenetic analysis using the nuclear DNA internal transcribed spacer (ITS) region revealed that W. fragrans falls within the Wikstroemia clade; based on current sampling, W. fragrans is closely-related to W. capitata. It is also the first species of Wikstroemia known to be endemic to the Danxia landform and is classified provisionally as Critically Endangered according to the IUCN Red List Categories and Criteria.

Pilea danxiaensis L.F.Fu, A.K.Monro & Y.G.Wei, a new species of Urticaceae from Danxia landform, Guangdong, China, is described and photographed. Phylogenetic analyses based on three DNA regions (ITS, trnL-F and rbcL) suggest that the new species belongs to P. sect. Pilea. Within the section, the new species is morphologically most similar to P. sinocrassifolia and P. peploides. Plastid genome and ribosomal DNA (rDNA) sequences of the new species are assembled and annotated. The plastid genome is 151,857 bp in length and comprises two inverted repeats (IRs) of 25,307 bp separated by a large single-copy of 82,836 bp and a small single-copy of 18,407 bp. A total of 113 functional genes are recovered, comprising 79 protein-coding genes, 30 tRNA genes, and four rRNA genes. A global conservation assessment suggests that P. danxiaensis should be classified as of Least Concern (LC).

Paraphlomis jinggangshanensis (Lamiaceae), a new species from Jiangxi Province, China, is described and illustrated. The new species is morphologically similar to P. intermedia, but can be easily distinguished from the latter by its cordate leaf base (vs. cuneate, decurrent), stem and calyx tube with glandular hairs (vs. short pubescent), and glabrous anthers (vs. ciliate anthers). A phylogenetic analysis, based on ITS regions, suggests that P. jinggangshanensis represents a separate branch in Paraphlomis and is closely related to Clade II. It is currently known only from Jinggangshan National Natural Reserve. Because of its limited distribution and small population size, the species was assessed as Near Threatened (NT) according to the IUCN Red List Categories and Criteria.

Asplenium jiulianshanense, a new tetraploid fern species of the A. normale complex (Aspleniaceae) from Jiulianshan National Nature Reserve, southern Jiangxi, China is described and illustrated. We inferred the phylogenetic position of the new species based on sequences from seven plastid markers (atpB, rbcL, rps4, rps4-trnS, trnL, trnL-F, and trnG) and one low-copy nuclear gene, pgiC. The plastid phylogeny supported a close relationship among the new species A. jiulianshanense, A. minutifolium, and A. kiangsuense, while the nuclear phylogeny differed in topology from the plastid tree. The new species may be due to hybridization between A. kiangsuense and A. boreale. Morphologically, the new species can easily be distinguished from other members of the A. normale complex by rachises bearing a gemma near the apex, pinna margins entire to sparsely crenate, and (1‒)3‒4(‒6) sori per pinna.

The diverse members of the genus Daphne are prized for their fragrant flowers. Despite being promising ornamental plants in many countries, genetic information of Daphne is scarce. In this study, the plastomes of four species and one variety of Daphne were sequenced and analyzed. The plastomes were typical and contained a pair of inverted repeat (IR) regions that separated the large single-copy (LSC) region from the small single-copy (SSC) region. With a length ranging from 132,869 bp (D. genkwa) to 174,773 bp (D. championii), 106 to 141 genes were predicted. Comparative plastome analysis of the newly sequenced plastomes with four publicly available Daphne plastomes identified an expansion of the IRs, sequence variations, and mutational hotspots. Phylogenetic analyses indicated that the genus Daphne in its current circumscription is polyphyletic. Daphne genkwa was nested within the genus Wikstroemia, while D. championii was well resolved as sister to Edgeworthia. These findings concurred with results from our study that used nuclear ribosomal internal transcribed spacer sequence data. The conflicts on the molecular placement of D. championii and D. genkwa and the present taxonomic classification in Daphne suggest that a new intergeneric classification system of Daphneae warrants consideration.

The Asplenium coenobiale complex is distributed in Eastern Asia and Southeast Asia with its distribution center in southwestern China. In this study, we carried out a detailed morphological, cytological, and phylogenetic study by adding two samples from Danxia landform in Guangdong. The sequences of five chloroplast markers and one nuclear marker of the A. coenobiale complex were analyzed with maximum likelihood and Bayesian inference, respectively. The morphological and phylogenetic analyses support the recognition of a new species (A. danxiaense K.W.Xu sp. nov.) of the A. coenobiale complex from a cave of Danxia mountain, Guangdong province, southern China. This new species can be distinguished from A. coenobiale and A. pulcherrimum by having scales narrowly triangular to lanceolate, apex ending in a short apical tail, basal basiscopic pinnule usually largest, fertile segment scarce, and exospore length usually more than 50 μm and shows significant molecular differences from other species in this complex. A detailed description and illustrations are presented.

The article discusses research which examined the possible mediation of the relationship between predation risk and crypsis by brain size. Topics explored include the cognitive abilities of well-camouflaged animals that help them evade predators, the use of reflectance measurements and visual modeling to assess the conspicuousness of anuran species from China, and observations relating to predation pressure, relative brain size, and hind leg muscle mass in the frogs studied.

Sexual dimorphism is regarded as the consequence of differential responses by males and females to selection pressures. Limb muscle plays a very important role during amplexus, which is likely to be under both natural and sexual selection in anurans. Here, we studied the effects of natural and sexual selection on limb muscle mass in males and females across 64 species of anurans. The results showed that there were non-significant differences in relative limb muscle mass between the sexes among species, exhibiting no sexual dimorphism in limb muscle. Absolute and relative limb muscle mass positively displayed correlations with snout-vent length (SVL)for both sexes. However, neither male-biased operational sex ratio (OSR) nor environmental harshness [e.g., coefficient of variation (CV) in temperature and CV in rainfall] can explain relative limb muscle mass (e.g., forelimb, hindlimb, and total limb muscle) within each sex. The findings suggest that environmental harshness and sexual selection cannot play important roles in promoting variations in limb muscle among anuran species.