The impact of grazing on seedling patterns in degraded sparse‐elm grassland

Over‐grazing by livestock in semi‐arid ecosystems is one of the main causes of desertification. Although over‐grazing presents a global environmental challenge, only a few studies have investigated grazing impacts on the composition of species and functional groups of seedling bank. In this study, we determined whether the composition of seedling species and functional groups, as well as the correlations between the seedlings of sparse‐elm (Ulmus pumila var. sabulosa or U. pumila) and other species changed under three grazing intensities in the degraded sparse‐elm grassland in the Horqin Sandy Land, China. Species composition and abundance of established seedlings were surveyed and the relationships between seedlings of U. pumila and other species were analyzed. The results showed that plant communities under moderate grazing were more stable than the other two grazing intensities due to higher seedling density, higher species richness and higher number of perennial herbs. Seedlings of U. pumila could even prevent noxious seedlings growth under moderate grazing. We concluded that moderate grazing could benefit the recovery of this sparse‐elm grassland in the Horqin Sandy Land

A 3D-printed microfluidic-enabled hollow microneedle architecture for transdermal drug delivery.

Embedding microfluidic architectures with microneedles enables fluid management capabilities that present new degrees of freedom for transdermal drug delivery. To this end, fabrication schemes that can simultaneously create and integrate complex millimeter/centimeter-long microfluidic structures and micrometer-scale microneedle features are necessary. Accordingly, three-dimensional (3D) printing techniques are suitable candidates because they allow the rapid realization of customizable yet intricate microfluidic and microneedle features. However, previously reported 3D-printing approaches utilized costly instrumentation that lacked the desired versatility to print both features in a single step and the throughput to render components within distinct length-scales. Here, for the first time in literature, we devise a fabrication scheme to create hollow microneedles interfaced with microfluidic structures in a single step. Our method utilizes stereolithography 3D-printing and pushes its boundaries (achieving print resolutions below the full width half maximum laser spot size resolution) to create complex architectures with lower cost and higher print speed and throughput than previously reported methods. To demonstrate a potential application, a microfluidic-enabled microneedle architecture was printed to render hydrodynamic mixing and transdermal drug delivery within a single device. The presented architectures can be adopted in future biomedical devices to facilitate new modes of operations for transdermal drug delivery applications such as combinational therapy for preclinical testing of biologic treatments

Biological Adsorption and Accumulation Analysis of Hizikia fusiforme Response to Copper Stress Conditions

Coastal water pollution is an important environmental problem now days. Hizikia fusiforme is cultivated in coastal water, being considered as a healthy food. However, little information exists concerning on this species responses to copper stress conditions. Experiments were conducted to distinguish biological adsorption and biological accumulation of H. fusiforme in regard to copper stress; it was determined the long-term stress with lower concentrations of copper (0.25 mg/L and 0.50 mg/L) and short-term stress with higher concentrations of copper (1.5 mg/L and 3.0 mg/L) on H. fusiforme. Results suggested that H. fusiforme has different response to various copper stresses; lower concentration stress could significantly enhance the growth of H. fusiforme, while H. fusiforme growth was inhibited and mitigated injured by 0.25-0.50 mg/L copper stress. Under the highest stress, H. fusiforme was extremely harmed, the biomass loss was significant and dry weight/fresh weight was also significantly decreased. Results suggested that lower and higher concentrations of copper stress have different impacts on H. fusiforme; the biological adsorption amount is lower than that of biological accumulation amount under low copper stress conditions, but the biological adsorption amount is much higher under high concentration copper stress. A better understanding of H. fusiforme responses to heavy metal stress should bring more data about its physiological adaptation mechanism under such conditions

Spatial-Division Augmented Occupancy Field for Bone Shape Reconstruction from Biplanar X-Rays

Retrieving 3D bone anatomy from biplanar X-ray images is crucial since it can significantly reduce radiation exposure compared to traditional CT-based methods. Although various deep learning models have been proposed to address this complex task, they suffer from two limitations: 1) They employ voxel representation for bone shape and exploit 3D convolutional layers to capture anatomy prior, which are memory-intensive and limit the reconstruction resolution. 2) They overlook the prevalent occlusion effect within X-ray images and directly extract features using a simple loss, which struggles to fully exploit complex X-ray information. To tackle these concerns, we present Spatial-division Augmented Occupancy Field~(SdAOF). SdAOF adopts the continuous occupancy field for shape representation, reformulating the reconstruction problem as a per-point occupancy value prediction task. Its implicit and continuous nature enables memory-efficient training and fine-scale surface reconstruction at different resolutions during the inference. Moreover, we propose a novel spatial-division augmented distillation strategy to provide feature-level guidance for capturing the occlusion relationship. Extensive experiments on the pelvis reconstruction dataset show that SdAOF outperforms state-of-the-art methods and reconstructs fine-scale bone surfaces.The code is available at https://github.com/xmed-lab/SdAOFComment: Accepted to MICCAI 2024. Project link: https://github.com/xmed-lab/SdAO

Effects of NaCl Stress on the Growth and Physiological Changes in Oat (Avena sativa) Seedlings

The oat (Avena sativa) is a kind of cereal grain, which has high saline-alkali tolerance. This experiment was carried out to investigate and compare the growth and physiological changes of oat seedling. Oat was grown under five concentrations of NaCl stress (48, 72, 96, 120 and 144 mmolL-1). The results showed that NaCl stress had no effect on the survival rate and organic acids. With the increasing of the NaCl concentration, tiller number, the chlorophyll, K+, Ca2+, NO3-, H2PO4- contents, shoot length, the shoot biomass, and shoot water content were decreased significantly. However, the Cl-, Na+, Na+/K+, SO42- and proline contents were extremely increased. K+, Ca2+, dry weight, and water content of shoots changed greater than that of roots. While Na+ and Na+/K+ of shoots changed less than that of roots. When NaCl concentration was less than 96 mmolL-1, the length, dry weight, and water content of roots had no significant changes. Based on this investigation, it can be concluded that oat seedlings accumulated more proline, Cl- and SO42- to maintaining osmotic and ion balance. In addition, NaCl stress had no significant effect on the growth of roots, and the roots can play the interceptive and protective role with a stronger salt tolerance. The roots can change the distribution of Na+, then it decreased the harm on the shoots and increased the tolerance of oat seedling

Effects of Saline and Alkaline Stresses on Growth and Physiological Changes in Oat (Avena sativa L.) Seedlings

Two neutral salts (NaCl and Na2SO4) and alkaline salts (NaHCO3 and Na2CO3) were both mixed in 2:1 ratio, and the effects of saline and alkaline stresses on growth and physiological changes in oat seedlings were explored. The result showed that biomass, water content and chlorophyll content decreased while cell membrane permeability significantly increased under alkaline stress. Saline stress did not have an obvious effect on pH value in tissue fluids of shoot and root, but alkaline stress increased pH value in the root tissue fluid. The contents of Na+, Na+/K+, SO42- increased more, and K+, NO3-, H2PO4- decreased more under alkaline stress, the Cl- content increased obviously under saline stress but had little change under alkaline stress. The increments of proline and organic acid were both greater under alkaline stress, but organic acid content kept the same level under saline stress. Alkaline stress caused more harmful effects on growth and physiological changes in oat seedlings especially broke the pH stability in the root tissue fluid. Physiological adaptive mechanisms of oat seedlings under saline stress and alkaline stress were different, which mainly took the way of accumulating organic acid under alkali stress but accumulating Cl- under saline stress

Surgical management of papillary thyroid carcinoma coexisting with Hashimoto’s disease: a single-center retrospective cohort study

BackgroundThe mechanism and impact of Hashimoto’s disease (HT) in patients with papillary thyroid carcinoma (PTC) remains a subject of ongoing debate. The optimal extent of thyroid resection is also controversial in cases of low-risk PTC.ObjectiveTo investigate the clinical outcomes and prognoses associated with different extents of surgical resection in patients diagnosed with PTC coexisting with HT.MethodsWe retrospectively analyzed data on the clinical features and treatment outcomes of patients with PTC concomitant with HT who underwent lobectomy with isthmusectomy and those who underwent total thyroidectomy at Peking University International Hospital between December 2014 and August 2023.ResultsTwenty-one patients in group A underwent lobectomy with isthmusectomy and prophylactic central neck dissection, whereas twenty patients in group B underwent total thyroidectomy with prophylactic central lymph node (LN) dissection, except one who did not undergo LN dissection. Group A demonstrated shorter surgery time (105.75 min ± 29.35 vs. 158.81 min ± 42.01, p = 0.000), higher parathyroid hormone (PTH) levels on postoperative day 1 [26.96 pg/ml (20.25, 35.45) vs. 9.01 pg/ml (2.48, 10.93), p = 0.000] and a shorter postoperative hospital stay [2.95 d (2.0, 4.0) vs. 4.02 d (3.0, 5.0), p = 0.008] than those of group B, with statistically significant differences. Both groups exhibited similar recovery patterns in terms of PTH [32.10 pg/ml (22.05, 46.50) vs. 20.47 pg/ml (9.43, 34.03), p = 0.192] and serum calcium (2.37 mmol/L ± 0.06 vs. 2.29 mmol/L ± 0.19, p = 0.409) after 1 montsh following the surgery. According to the Kaplan-Meier curves, no significant difference in the 5-year disease-free survival rates were observed between patients in group A (100%) and group B (97.1%) (Log rank test: p = 0.420, Breslow test: p = 0.420).ConclusionLobectomy with isthmusectomy and prophylactic central neck dissection is a safe and feasible treatment option for patients with low-risk PTC coexisting with HT.Clinical trial registrationhttp://www.chictr.org.cn, identifier ChiCTR2300079115

Physiological Adaptive Strategies of Oil Seed Crop Ricinus communis Early Seedlings (Cotyledon vs. True Leaf) Under Salt and Alkali Stresses: From the Growth, Photosynthesis and Chlorophyll Fluorescence

Ricinus communis is an important energy crop and is considered as one of the most potential plants for salt-alkali soil improvement in Northeast China. Early seedling stage (such as the cotyledon expansion stage) is always a vulnerable stage but plays a vital role in plant establishment, especially under stress conditions. However, little information exists concerning the function of cotyledon and the relationship between cotyledon and true leaf in the adaptation to salt stress and alkali stress of this species. Here, Ricinus communis seedlings were treated with varying (40, 80 and 120 mM) salinity (NaCl) and alkalinity (NaHCO3), growth, photosynthesis, and chlorophyll fluorescence of cotyledons and true leaves were measured. The results showed that the biomass, photosynthetic parameters, and the qp value of both cotyledons and true leaves decreased with increasing salt-alkali stress, and the decrease in biomass, gs and Tr, of true leaves were much greater than that of cotyledons. Salt-alkali stress only reduced photosynthetic pigments and ΦPSII in cotyledons, but did not affect those in true leaves. Additionally, the Fv/Fm and NPQ between cotyledons and true leaves showed different trends in salinity and alkalinity. The results suggested that alkali stress could cause much more damage to the castor bean seedlings, and different physiological responses and adaptive strategies are found in cotyledons and true leaves under salt-alkali stress. This study will help us develop a better understanding of the adaptation mechanisms of cotyledon and true leaf during early seedling stage of castor bean plant, and also provide new insights into the function of cotyledon in Ricinus communis under salt-alkali stress conditions

Robust Inventory Financing Model with Partial Information

Given current fast-changing market conditions and difficulty in obtaining financing for small- and medium-sized enterprises, this paper studies the robust inventory financing model under partial information, that is, where the demand distribution is partly known. Two demand information cases are discussed: (1) the mean and variance and (2) the support of the demand distribution. In this setting, the robust method that maximizes the worst-case profit and minimizes the firm’s maximum possible regret of not acting optimally would be used to formulate the optimal sales quantity. We show that the approach used in this paper is tractable, and we provide an explicit expression for the robust optimal policy. We then use numerical examples to compare the firm’s losses under two demand information cases with those occurring under demand certainty. More importantly, the numerical examples indicate that our robust inventory financing model can obtain a robust but not conservative solution

The rubber tree genome reveals new insights into rubber production and species adaptation

The Para rubber tree (Hevea brasiliensis) is an economically important tropical tree species that produces natural rubber, an essential industrial raw material. Here we present a high-quality genome assembly of this species (1.37 Gb, scaffold N50 = 1.28 Mb) that covers 93.8% of the genome (1.47 Gb) and harbours 43,792 predicted protein-coding genes. A striking expansion of the REF/SRPP (rubber elongation factor/small rubber particle protein) gene family and its divergence into several laticifer-specific isoforms seem crucial for rubber biosynthesis. The REF/SRPP family has isoforms with sizes similar to or larger than SRPP1 (204 amino acids) in 17 other plants examined, but no isoforms with similar sizes to REF1 (138 amino acids), the predominant molecular variant. A pivotal point in Hevea evolution was the emergence of REF1, which is located on the surface of large rubber particles that account for 93% of rubber in the latex (despite constituting only 6% of total rubber particles, large and small). The stringent control of ethylene synthesis under active ethylene signalling and response in laticifers resolves a longstanding mystery of ethylene stimulation in rubber production. Our study, which includes the re-sequencing of five other Hevea cultivars and extensive RNA-seq data, provides a valuable resource for functional genomics and tools for breeding elite Hevea cultivars. The rubber tree (Hevea brasiliensis, hereafter referred to as Hevea) is a member of the spurge family (Euphorbiaceae), along with several other economically important species such as cassava (Manihot esculenta) and the castor oil plant (Ricinus communis). Natural rubber (cis-1, 4-polyisoprene) makes up about one-third of the volume of latex that is essentially cytoplasm of the articulated laticifers in Hevea. The latex is extracted by tapping the bark, a non-destructive method of harvesting that facilitates continual production. As an industrial commodity, natural rubber is an elastomer with physical and chemical properties that cannot be fully matched by synthetic rubber1. In contrast to synthetics, the production of natural rubber is sustainable and environment friendly2. The commercial cultivation of Hevea, a native to the Amazon Basin, began in 1896 on a plantation scale in Malaya (now Malaysia) and expanded to other Southeast Asian countries that lead in world natural rubber production today3. Decades of selective breeding have resulted in a gradual improvement in rubber productivity, from 650 kg ha–1 derived from unselected seedlings during the 1920s to 2,500 kg ha–1 yielded by elite cultivars by the 1990s4. Nevertheless, the field production achieved so far is still well below the theoretical yield of 7,000–12,000 kg ha–1, as has been suggested for the rubber tree5. Meanwhile, conventional rubber breeding has been stagnating in the introduction of high-yield cultivars. The reasons include a narrow genetic basis for exploiting breeding potential and difficulty in introducing wild germplasms because of the genetic burden in removing unfavourable alleles6. The incorporation of marker-assisted selection and transgenic techniques offers promise to improve breeding efficiency for latex yield, and sequencing of the Hevea genome would uncover even more avenues leading to this end. The first draft Hevea genome was released by a Malaysian team7 that was participant to the recent boom in transcriptomic and proteomic studies of the species8,9,10,11. However, its low sequence coverage (∼13×) and a lack of large insert libraries (such as fosmid- or BAC-based clone libraries) have limited the success of genome assembly (a scaffold N50 size of 2,972 bp), precluding its application for furthering quality research in the field. Here, we report a high-quality genome assembly of Hevea Reyan7-33-97, an elite cultivar widely planted in China12,13 based on sequence data from both whole-genome shotgun (WGS) and pooled BAC clones. This assembly contains 7,453 scaffolds (N50 = 1.28 Mb), has a length of 1.37 Gb and covers ∼94% of the predicted genome size (1.46 Gb). Together with analysis of data from re-sequencing five other cultivars and comprehensive transcriptomic surveys, we aim to obtain new insights into the physiology of laticifers and molecular details of rubber biosynthesis, especially in relation to ethylene-stimulated rubber production. (Résumé d'auteur