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In order to develop a near-infrared band fiber grating external cavity semiconductor laser for quantum precision measurement applications, a high polarization dependent gain chip and a birefringent fiber Bragg grating were designed independently, the effects of grating reflectivity, external cavity, and chip length on laser linewidth were systematically analyzed based on the Fabry-Pérot equivalent resonant cavity model. The results shows that the developed laser achieves an output power of 54.46 mW, a side mode suppression ratio of 58.88 dB, and a polarization extinction ratio of 24.46 dB. The Lorentz linewidth measured is 2.69 kHz by delayed self-heterodyne beat frequency method. This study provides a reference for the single frequency narrow linewidth external cavity semiconductor lasers with independent design and preparation of discrete devices, and is expected to be used in quantum precision measurement fields such as radar imaging, gyroscopes, magnetometers, and atomic clocks. [ABSTRACT FROM AUTHOR]

Background: Human papillomavirus (HPV) infection has become an important etiological driver of oropharyngeal squamous cell carcinoma (OPSCC), leading to unique tumor characteristics. However, the interplay between HPV-associated tumor cells and tumor microenvironment (TME) remains an enigma. Methods: We performed a single-cell RNA-sequencing (scRNA-seq) on HPV-positive (HPV+) and HPV-negative (HPV‒) OPSCC tumors, each for three samples, and one normal tonsil tissue. Ex vivo validation assays including immunofluorescence staining, cell line co-culture, and flow cytometry analysis were used to test specific subtypes of HPV+ tumor cells and their communications with T cells. Results: Through a comprehensive single-cell transcriptome analysis, we uncover the distinct transcriptional signatures between HPV+ and HPV‒ OPSCC. Specifically, HPV+ OPSCC tumor cells manifest an enhanced interferon response and elevated expression of the major histocompatibility complex II (MHC-II), potentially bolstering tumor recognition and immune response. Furthermore, we identify a CXCL13+CD4+ T cell subset that exhibits dual features of both follicular and pro-inflammatory helper T cells. Noteworthily, HPV+ OPSCC tumor cells embrace extensive intercellular communications with CXCL13+CD4+ T cells. Interaction with HPV+ OPSCC tumor cells amplifies CXCL13 and IFNγ release in CD4+T cells, fostering a pro-inflammatory TME. Additionally, HPV+ tumor cells expressing high MHC-II and CXCL13+CD4+ T cell prevalence are indicative of favorable overall survival rates in OPSCC patients. Conclusions: Together, our study underscores a synergistic inflammatory immune response orchestrated by highly immunogenic tumor cells and CXCL13+CD4+ T cells in HPV+ OPSCC, offering useful insights into strategy development for patient stratification and effective immunotherapy in OPSCC. [ABSTRACT FROM AUTHOR]

OBJECTIVES Thoracoscopic segmentectomy is the recommended treatment option for small peripheral pulmonary nodules. To assess the ability of preoperative three-dimensional (3D) reconstruction computed tomography (CT) to shorten the operative time and improve perioperative outcomes in thoracoscopic segmentectomy compared with standard chest CT, we conducted this randomized controlled trial. METHODS The DRIVATS study was a multicentre, randomized controlled trial conducted in 3 hospitals between July 2019 and November 2023. Patients with small peripheral pulmonary nodules not reaching segment borders were randomized in a 1:1 ratio to receive either 3D reconstruction CT or standard chest CT before thoracoscopic segmentectomy. The primary end-point was operative time. The secondary end-points included incidence of postoperative complications, intraoperative blood loss and operative accident event. RESULTS A total of 191 patients were enrolled in this study: 95 in the 3D reconstruction CT group and 96 in the standard chest CT group. All patients underwent thoracoscopic segmentectomy except for 1 patient in the standard chest CT group who received a wedge resection. There is no significant difference in operative time between the 3D reconstruction CT group (median, 100 min [interquartile range (IQR), 85–120]) and the standard chest CT group (median, 100 min [IQR, 81–140]) (P  =   0.82). Only 1 intraoperative complication occurred in the standard chest CT group. No significant difference was observed in the incidence of postoperative complications between the 2 groups (P  =   0.52). Other perioperative outcomes were also similar. CONCLUSIONS In patients with small peripheral pulmonary nodules not reaching segment borders, the use of 3D reconstruction CT in thoracoscopic segmentectomy was feasible, but it did not result in significant differences in operative time or perioperative outcomes compared to standard chest CT. [ABSTRACT FROM AUTHOR]

Background: Human papillomavirus (HPV)-associated head and neck squamous cell carcinoma (HNSCC) is an evolving and growing disease, especially in developing countries. However, the clinical characteristics of HPV-associated HNSCC in regard to HPV infection rates, patient features, and prognosis are under-reported in the Asian population. Methods: In this study, we retrospectively enrolled a 400-case cohort of HNSCC with p16 immunochemistry and analyzed with long-term follow-up. We investigate the current HPV prevalence of HNSCC, unique HPV-associated patient clinical characteristics, and patient prognosis in the southern China population. Results: HPV infection exhibited a 15% prevalence in all HNSCC cases, notably higher in oropharyngeal cases (30.7%), followed by oral cavity (11.8%), laryngeal (10.1%), and hypopharyngeal (2.5%). HPV status, gender, old age, and location of tumor were significantly associated with the patient's survival. Tonsil invasion was found more frequent in HPV-positive oropharyngeal HNSCC than in HPV-negative cases. HPV-associated HNSCC patients tend to possess stronger tobacco and alcohol habits, which were correlated to poor survival. HPV status's correlation with gender, age, and anatomical location is associated intricately with patient survival. The secondary primary tumor rate was found higher within the HPV-negative group, compared to the HPV-positive group (9.12% versus 1.67%). Conclusion: Our study provided a current picture of HPV-associated HNSCC in the southern China population and elaborated the understanding of key factors that correlate to HNSCC prognosis. Our findings indicated a strong susceptibility of HPV-associated oropharyngeal HNSCC in the tonsil and the difference in secondary primary tumor rates associated with HPV status. Plain language summary: HPV in head and neck cancer In this study, we retrospectively enrolled a 400-case cohort of HNSCC with p16 immunochemistry and analyzed with long-term follow-up. We investigate the current HPV prevalence of HNSCC, unique HPV-associated patient characteristics, along with patient prognosis in southern China population. Our findings indicated a strong susceptibility of HPV-associated oropharyngeal HNSCC in tonsil and difference of secondary primary tumor associated with HPV status. Our study provided a current picture of HPV-associated HNSCC in southern China population and elaborated the understanding of key factors that correlate to HNSCC prognosis. [ABSTRACT FROM AUTHOR]

Background The fat mass and obesity-associated protein (FTO) is an RNA demethylase that contributes to several physiological processes. Nonetheless, the impact of FTO on bone remodeling in the midpalatal suture while undergoing rapid maxillary expansion (RME) remains unclear. Methods First, to explore the expression of FTO in the midpalatal suture during RME, six rats were randomly divided into two groups: Expansion group and Sham group (springs without being activated). Then, suture mesenchymal stem cells (SuSCs) were isolated as in vitro model. The expression of FTO was knocked down by small interfering RNA to study the effect of FTO on the osteogenic differentiation of SuSCs. Finally, to evaluate the function of FTO in the process of bone remodeling in the midpalatal suture, ten rats were randomly divided into two groups: FB23-2 group (10 μM, a small molecule inhibitor of FTO) and DMSO group (control). Results Increased arch width and higher expression of OCN and FTO in the midpalatal area were observed in expansion group (P  < .05). In the in vitro model, the mRNA expression levels of Runx2, Bmp2, Col1a1, Spp1, and Tnfrsf11b were decreased (P  < .05) upon knocking down FTO. Additionally, the protein levels of RUNX2 and OPN were also decreased (P  < 0.05). Adding FB23-2, a small-molecule inhibitor targeting FTO, to the medium of SuSCs caused a decrease in the mRNA expression levels of Runx2, Bmp2, Col1a1, Spp1, and Tnfrsf11b (P  < 0.05). There was a statistically significant difference in evaluating the expression of OCN and OPN on the palatal suture between the FB23-2 and DMSO groups (P  < .05). Limitation The molecular mechanisms by which FTO regulates SuSCs osteogenesis remain to be elucidated. The FTO conditional knock out mouse model can be established to further elucidate the role of FTO during RME. Conclusion FTO contributes to the osteogenic differentiation of SuSCs and plays a promoting role in midpalatal suture bone remodeling during the RME. [ABSTRACT FROM AUTHOR]

Objective: Apical periodontitis is the most frequently occurring pathological lesion. Fat mass and obesity‐associated protein (Fto) is the first identified RNA N6‐methyladenosine demethylase. However, whether Fto regulates apical periodontitis remains unclear. This study aimed to explore the mechanisms of Fto in the tumor necrosis factor‐α (TNF‐α)‐induced inflammatory response. Materials and Methods: We established an apical periodontitis model. An immortalized cementoblast cell line (OCCM‐30) cells were exposed to TNF‐α. Fto, Il6, Mcp1, and Mmp9 expressions were assessed by qRT‐PCR. We knocked down Fto using lentiviruses and detected TNF‐α‐induced inflammation‐related gene expressions and mRNA stability. Results: Mice with apical periodontitis showed downregulation of Fto expression. OCCM‐30 cells exposed to TNF‐α showed an upregulation of inflammation‐related genes with a decrease in Fto. Furthermore, knockdown of Fto promoted the expressions of Il6, Mcp1, and Mmp9 in TNF‐α‐treated OCCM‐30 cells as compared with negative control cells, whereas it did not affect the mRNA stability. Interestingly, Fto knockdown activated the p65, p38, and ERK1/2 pathways, and it slightly activated the JNK signaling pathway after TNF‐α administration in OCCM‐30 cells. Conclusion: A TNF‐α‐induced decrease in the expression of Fto might play a critical role in the inflammatory response in cementoblasts, and knockdown of Fto might upregulate the inflammatory response. [ABSTRACT FROM AUTHOR]

Sheath/core bicomponent spinning can be utilized to produce functional fibers with high application value such as plastic optical fibers. The core offset configuration formed during spinning is to the detriment of the performance of the fibers. Owing to the limitation of the experiment that is difficult to disclose the formation mechanism of the core offset, numerical simulation was carried out to study the sheath/core interface distribution during spinning. The results showed that individual variations of the viscosity ratio and composition ratio will not lead to the core offset defect through an ideal channel. In the case of non-ideal channel structure, the flow rate unevenness of the sheath component and the coaxiality of the core tube and the orifice played major roles in the core offset configuration, while the effect of declination of the core tube can be negligible. The degree of core offset caused by the coupling effect of the flow rate unevenness of the sheath component and the coaxiality of the core tube and the orifice was equal to the linear superposition of the single effect. Based on the sheath/core axis deviation under different conditions, it was demonstrated that the core offset defect can be inhibited by reducing the proportion of the sheath component in any case, which has a guiding significance for the production of the sheath/core bicomponent fiber. [ABSTRACT FROM AUTHOR]

Although similar to trunk and limb skeletal muscles, masticatory muscles are believed as unique in both developmental origins and myogenesis. Gαi2 has been demonstrated to promote muscle hypertrophy and muscle satellite cell differentiation in limb muscles. However, the effect of Gαi2 on masticatory muscles is still unexplored. This study aimed to identify the role of Gαi2 in the proliferation and differentiation of masticatory muscle satellite cells, further exploring the metabolic mechanism of masticatory muscles. The proliferation rate, myotube size, fusion index of masticatory muscle satellite cells and Pax7, Myf5, MyoD, Tcf21 and Musculin expressions were significantly decreased by Gαi2 knockdown, while in cells infected with AdV4‐Gαi2, the proliferation rate, myotube size, fusion index and Tbx1 expression were significantly increased. Masticatory muscle satellite cells also displayed phenotype transformation as Gαi2 changed. In addition, Gαi2 altered myosin heavy chain (MyHC) isoforms of myotubes with less MyHC‐2A expression in siGαi2 group and more MyHC‐slow expression in AdV4‐Gαi2 group. In conclusion, Gαi2 could positively affect the adult myogenesis of masticatory muscle satellite cells and maintain the superiority of MyHC‐slow. Masticatory muscle satellite cells may have their unique Gαi2‐regulated myogenic transcriptional networks, although they may share some common characteristics with trunk and limb muscles. [ABSTRACT FROM AUTHOR]

Due to the particularity of loess engineering geology, loess railway tunnel accidents occur frequently. Based on the theoretical basis of risk management, this study evaluated the service performance of loess railway tunnels. Based on the improved TOPSIS method, the indirect proximity degree of each risk factor was compared, and the appropriate service performance evaluation index was selected. Based on the ISM model and the causality graph modification method, the dependency relationship between nodes was obtained and the Bayesian network evaluation model was constructed. By constructing the database, the EM algorithm was used for data learning, and the model was trained and verified, and the overall accuracy (ACC) and F1 value are used to comprehensively evaluate the training and prediction effect of the model. Finally, the evaluation model was applied to a tunnel case. The results show that the established Bayesian network model has a high accuracy of 92%, which is easy to operate, effective and practical, and it is also applicable in situations of incomplete index statistical data. [ABSTRACT FROM AUTHOR]

As a result of the limitation of bicomponent spinning in which it is difficult to obtain the interface evolution of the fiber forming process and guarantee performance stability, numerical simulation was carried out to investigate the effect of cooling, melt viscosity, and inlet flow rate on the interface throughout the process. The results showed that the position deviation of the interface only occurred inside the orifice and the interface distortion continued until after extrusion, with the maximum deformation occurring during extrusion swelling. Based on sufficient multifield data obtained from the simulation, it was demonstrated that the interfacial curvature was governed only by the viscosity difference between individual components, and the position of the interface was determined by the mechanical energy of the bicomponent melt. Moreover, the curvature and the position of the interface can be adjusted indirectly by changing the viscosity ratio, which can be regulated by the flow ratio, bringing guidance for the full process control of the bicomponent fiber preparation. [ABSTRACT FROM AUTHOR]

Background and Objectives: Peroxisome proliferator‐activated receptor‐γ coactivator (PGC)‐1α, a master regulator of mitochondrial biogenesis and oxidative metabolism, has been associated with many inflammatory diseases. However, little is known about the function and mechanism of PGC‐1α in cementoblasts under periodontitis. Our study aimed to investigate the effects of PGC‐1α in immortalized cementoblast cell line OCCM‐30 under TNF‐α stimulation. Materials and Methods: OCCM‐30 cells were cultured and exposed to TNF‐α, and PGC‐1α expression was assessed by Quantitative real‐time polymerase chain reaction (qRT‐PCR) and western blotting. Chemical inhibitors targeting various signaling pathways including NF‐κB, p38 MAPK, Akt, and p53 were used to identify the regulatory mechanism involved. ZLN005 was used to upregulate PGC‐1α and the subsequent alteration of inflammatory cytokines expression under TNF‐α stimulation were examined by qRT‐PCR and Elisa. PGC‐1α siRNA was employed to further verify the role of PGC‐1α in inflammatory response. Dual‐reporter gene assays were performed to examine the transcriptional activity of p65, and the phosphorylation level of p65 was evaluated by western blotting. Immunofluorescence assays and nuclear and cytoplasmic extractions were performed to check the nuclear translocation of p65. Coimmunoprecipitation studies were also performed to check whether there is direct binding between p65 and PGC‐1α. Results: TNF‐α suppressed PGC‐1α expression in OCCM‐30 cells. Blocking p38 MAPK pathways restored the expression of PGC‐1α. ZLN005 can upregulate PGC‐1α in OCCM‐30 cells. The upregulation of PGC‐1α by ZLN005 inhibited TNF‐α‐induced proinflammatory cytokine expression, which was impaired by the transfection of PGC‐1α siRNA. Knocking down PGC‐1α also partially restored the ZLN005‐decreased transcriptional activity of p65. However, the phosphorylation level and nuclear translocation of p65 were not significantly affected by PGC‐1α. It was found that p65 was bound to PGC‐1α in OCCM‐30 cells stimulated by TNF‐α, and the binding was increased upon ZLN005 treatment. Conclusions: PGC‐1α can attenuate TNF‐α‐induced inflammatory responses in OCCM‐30 cells. [ABSTRACT FROM AUTHOR]

The terrestrial methane budget varies between different vegetation types and soil conditions and is highly uncertain for alpine grasslands. This work used eddy covariance techniques to continuously measure CH4 flux (NEEm) over a semiarid alpine meadow on the northeastern Qinghai-Tibetan Plateau from January 2017 to August 2019. The diel NEEm averaged 0.14 ± 0.98 nmol CH4 m−2 s−1 (mean ± S.D.), with a rough pattern of daytime release and nocturnal uptake. The 8-day NEEm exhibited a similar sinusoid variation, with a peak of 6.8 mg CH4 m−2 d−1 at the end of April and a minimum of −1.5 mg CH4 m−2 d−1 at the end of August. The maximum release probably coincided with the thawing of frozen soil in the root zone, and the peak uptake may be related to high soil temperature. Monthly CH4 uptake was highest from June to September and consumed 51.7 mg CH4 m−2 from the atmosphere. CH4 production in the other months totaled 647.6 mg CH4 m−2. The semiarid alpine meadow thus acted as a weak net CH4 source, releasing ca 0.6 g CH4 m−2 year−1 to the atmosphere. The boosted regression trees analysis shows that the sensible heat flux (H) is positively related to half-hour NEEm and accounted for 34% of its variability. The piecewise structural equation models reveal that the magnitude of the effects from soil temperature and vapor pressure deficit on 8-day and monthly NEEm were almost equal, but acted in opposite directions. Vegetation growth and soil moisture exerted little direct influence on NEEm variability at half-hour, 8-day, or monthly scales. Our results show that CH4 emissions of the nongrowing season dominate the annual methane budget for this alpine meadow area. Methane consumption during the growing season was significantly constrained by low soil temperature and high soil water content. These findings imply that semiarid alpine meadows may consume more methane during the growing season if soil temperatures increase and soil moisture levels decrease as projected by future warming scenarios, thus constituting a climate change negative feedback. [ABSTRACT FROM AUTHOR]

Background and Objective: Cementum is a part of the periodontium and anchors periodontal ligaments to the alveolar bone. Cementoblasts are responsible for the cementum formation via matrix deposition and subsequently mineralization. Thus, exploring novel mechanisms underlying the function of cementoblast contributes to the treatment of cementum damage. Recently, circRNA Lrp6 (circLRP6) has been of interest due to its active role in cell differentiation, but its potential role in cementoblast differentiation remains unclear. Herein, we attempted to elucidate the role of circLRP6 in cementoblast differentiation and clarify any associated mechanisms. Material and Methods: The mRNA expressions of circLRP6, miR‐145a‐5p, zinc finger E‐box binding homeobox 2 (Zeb2), runt‐related transcription factor 2 (Runx2), osteopontin (Opn), and bone sialoprotein (Bsp) were evaluated by qRT‐PCR. The protein levels of Zeb2 were measured by Western blot. Bioinformatic analysis and dual‐luciferase reporter assays were used to test the potential binding targets of miR‐145a‐5p. The differentiation potentials of the cementoblasts were assessed by Alkaline phosphatase (ALP) staining, ALP activity assay, Alizarin red S (ARS) staining, and quantification. Results: In this study, circLRP6 was significantly upregulated in cementoblast differentiation. Furthermore, circLRP6 knockdown inhibited ALP levels, reduced calcium nodule formation and the expression of Runx2, Opn, and Bsp. Mechanically, bioinformatic analysis and dual‐luciferase reporter assays confirmed miR‐145a‐5p was a potential binding target of circLRP6. miR‐145a‐5p can negatively regulate cementoblast differentiation. Subsequently, bioinformatic analysis and dual‐luciferase reporter assays confirmed Zeb2 was a potential miR‐145a‐5p target. miR‐145a‐5p overexpression resulted in a downregulation of Zeb2. Furthermore, Zeb2 inhibition partially reversed the effect of circLRP6 during cementoblast differentiation. Conclusion: Taken together, circLRP6 appears to modulate cementoblast differentiation by antagonizing the function of miR‐145a‐5p, thereby increasing Zeb2. This study serves as a stepping stone for the potential development of an approach to promote cementum formation. [ABSTRACT FROM AUTHOR]

Pulmonary embolism (PE) is a common pathologic condition that frequently occurs in patients with deep venous thrombosis. Severe PE may critically suppress cardiopulmonary function, thereby threatening the life of patients. Chronic pulmonary hypertension caused by PE may lead to deterioration of respiratory dysfunction, resulting in complete disability. MicroRNAs (miRNAs) are a group of abundantly expressed non-coding RNAs that exert multiple functions in regulating the transcriptome via post-transcriptional targeting of mRNAs. Specifically, miRNAs bind to target mRNAs in a matching mechanism between the miRNA seed sequence and mRNA 3ʹ UTR, thus modulating the transcript stability or subsequent translation activity by RNA-induced silencing complex. Current studies have reported the function of miRNAs as biomarkers of PE, revealing their mechanism, function, and targetome in venous thrombophilia. This review summarizes the literature on miRNA functions and downstream mechanisms in PE. We conclude that various related miRNAs play important roles in PE and have great potential as treatment targets. For clinical application, we propose that miRNA biomarkers combined with traditional biomarkers or miRNA signatures generated from microchips may serve as a great predictive tool for PE occurrence and prognosis. Further, therapies targeting miRNAs or their upstream/downstream molecules need to be developed more quickly to keep up with the progress of routine treatments, such as anticoagulation, thrombolysis, or surgery. [ABSTRACT FROM AUTHOR]

Fluorescent labeling and dynamic tracking is a powerful tool for exploring virus infection mechanisms. However, for small-sized viruses, virus tracking studies are usually hindered by a lack of appropriate labeling methods that do not dampen virus yield or infectivity. Here, we report a universal strategy for labeling viruses with chemical dyes and Quantum dots (QDs). Enterovirus 71 (EV71) was produced in a cell line that stably expresses a mutant methionyl-tRNA synthetase (MetRS), which can charge azidonorleucine (ANL) to the methionine sites of viral proteins during translation. Then, the ANL-containing virus was easily labeled with DBCO-AF647 and DBCO-QDs. The labeled virus shows sufficient yield and no obvious decrease in infectivity and can be used for imaging the virus entry process. Using the labeled EV71, different functions of scavenger receptor class B, member 2 (SCARB2), and heparan sulfate (HS) in EV71 infection were comparatively studied. The cell entry process of a strong HS-binding EV71 strain was investigated by real-time dynamic visualization of EV71-QDs in living cells. Taken together, our study described a universal biocompatible virus labeling method, visualized the dynamic viral entry process, and reported details of the receptor usage of EV71. [ABSTRACT FROM AUTHOR]

Objective: miR‐146a is widely induced during the immune response. However, little is known about the biogenesis, function and mechanism of miR‐146a in cementoblasts during the pathogenesis of periodontitis. This study aimed to investigate the effects of miR‐146a in murine cementoblast‐derived OCCM‐30 cells following IL‐1β stimulation. Materials and methods: OCCM‐30 cells were cultured and exposed to IL‐1β. IL‐6, IL‐1β and TNF‐α, and miR‐146a‐5p expression was assessed by qRT‐PCR. Mimics/inhibitors were transiently transfected into cells to determine the function of miR‐146a‐5p. Signalling pathways including p38 MAPK, ERK1/2 and NF‐κB were studied by using specific inhibitors. The indicated proteins were measured by Western blot analysis and ELISA. Results: In IL‐1β‐stimulated OCCM‐30 cells, the expression levels of miR‐146a‐5p along with IL‐6 and IL‐1β increased in a time‐dependent manner. The ERK1/2, p38 MAPK and NF‐κB pathway were activated upon IL‐1β stimulation. Blocking the NF‐κB pathway decreased IL‐6, IL‐1β and miR‐146a‐5p expression. The overexpression of miR‐146a‐5p reduced IL‐6 and IL‐1β expression, while the inhibition of miR‐146a‐5p increased IL‐6 and IL‐1β expression in IL‐1β‐treated OCCM‐30 cells. miR‐146a‐5p attenuated IL‐6 and IL‐1β expression via the IRAK1/TRAF6 pathway. Conclusion: This study suggested that miR‐146a‐5p attenuates IL‐1β‐induced inflammatory factors in cementoblast‐derived cell line. [ABSTRACT FROM AUTHOR]

Objective: Irisin is a newly identified exercise‐induced myokine which can affect glucose metabolism and cortical bone mass and strength. However, the influence of irisin on cementoblasts remains largely unknown. Material and methods: An immortalized mouse cementoblast cell line OCCM‐30 was used in this study. Cementoblast differentiation markers and PGC‐1α in cells cultured with mineral induction medium were evaluated by qRT‐PCR. Cementoblast mineralization was evaluated by alizarin red staining. Differentiation markers and the activity of p38 MAPK pathway under irisin stimulation were assessed by qRT‐PCR or Western blot analysis. p38 MAPK pathway inhibitor SB203580 or p38 siRNA was used to further identify the regulatory mechanism. Cell proliferation treated with irisin was examined by CCK‐8 method. Results: The expression of Runx2, osterix, ALP, and PGC‐1α was up‐regulated consistently under mineral induction. The formation of mineralized nodules was increased by irisin. Runx2, osterix, ALP, and osteocalcin were obviously up‐regulated under irisin stimulation as well as the activity of p38 MAPK pathway. When pretreated with SB203580 or p38 siRNA before irisin stimulation, the irisin‐induced differentiation was distinctly suppressed. OCCM‐30 cell proliferation was enhanced when treated with high‐dose irisin for long time. Conclusion: Irisin can promote the differentiation of cementoblasts via p38 MAPK pathway. [ABSTRACT FROM AUTHOR]

Few studies have focused on the response of plant community phenology to temperature change using manipulative experiments. A lack of understanding of whether responses of community reproductive and vegetative phenological sequences to warming and cooling are asymmetrical or symmetrical limits our capacity to predict responses under warming and cooling. A reciprocal transplant experiment was conducted for 3 years to evaluate response patterns of the temperature sensitivities of community phenological sequences to warming (transferred downward) and cooling (transferred upward) along four elevations on the Tibetan Plateau. We found that the temperature sensitivities of flowering stages had asymmetric responses to warming and cooling, whereas symmetric responses to warming and cooling were observed for the vegetative phenological sequences. Our findings showed that coverage changes of flowering functional groups (FFGs; i.e., early-spring FFG, mid-summer FFG, and late-autumn FFG) and their compensation effects combined with required accumulated soil temperatureto codetermined the asymmetric and symmetric responses of community phenological sequences to warming and cooling. These results suggest that coverage change in FFGs on warming and cooling processes can be a primary driver of community phenological variation and may lead to inaccurate phenlogical estimation at large scale, such as based on remote sensing. [ABSTRACT FROM AUTHOR]

In this work, a three-dimensional DNA machine based on the isothermal strand-displacement polymerase reaction (ISDPR) has been constructed. The walking behavior of a DNA walker on the obstructive surface of magnetic beads has also been studied by adding different nucleic acid blocks. The "leg" of the DNA walker could hybridize with a hairpin structure DNA named H1 and lead to the opening of it. And the newly exposed stem would interact with a primer. A strand exchange has happened with the assistance of polymerase and dNTPs, so that the "leg" has been displaced and the DNA walker could be pushed to move on the surface. But the nucleic acid blocks could increase steric hindrance and obstruct this process, which is similar to the behavior of human beings walking on craggy paths. Through changing these blocks, such as the structure, the amount, and the length of blocks, the movement of the DNA walker has been controlled. What's more, the results of its application for DNA detection are satisfactory. The limit of detection is 21.6 pM. Also, this method has been successfully applied in complex biological samples. [ABSTRACT FROM AUTHOR]

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It has been reported that matrix metalloproteinases (MMPs) are induced by many cytokines, and they are involved in various inflammatory processes, including periodontitis. However, the effects of interleukin-1β (IL-1β) on MMP-9 expression in cementoblasts, the cells responsible for cementum production, remain largely unknown. In this study, we used qPCR and gelatin zymogram analysis to show that IL-1β upregulated MMP-9 expression in cementoblast-derived cell line. Several signaling pathways, such as ERK1/2, JNK, p38, and AP-1 (c-Fos and ATF-2), were activated in response to IL-1β stimulation. Furthermore, enhancement of AP-1 activity by IL-1β was further confirmed by the AP-1 reporter assay and the electrophoretic mobility shift assay (EMSA). Pretreatment with specific inhibitors of ERK1/2 (U0126), JNK (SP600125), and AP-1 (tanshinone IIA) attenuated IL-1β-induced MMP-9 expression. In addition, inhibitors of ERK1/2 (U0126) and JNK (SP600125) attenuated IL-1β-enhanced AP-1 activity. This suggested that IL-1β stimulated AP-1 activation, at least partially, through ERK1/2 and JNK signaling pathways. Moreover, we found that IL-1β also upregulated the expression of MMP-13 and enhanced MMP-mediated degradation of type I collagen. Collectively, these results suggested that IL-1β induced MMP-9 expression by activation of AP-1 through the ERK1/2 and JNK signaling pathways in cementoblast-derived cell line and enhanced MMP-mediated collagen degradation possibly by MMP-13 and MMP-9. [ABSTRACT FROM AUTHOR]

Autophagy is a self-digestive process that eliminates impaired or aged proteins and potentially toxic intracellular components to maintain homeostasis. We previously demonstrated that TNF-α played a critical role in cementoblast differentiation, mineralization and apoptosis; however, the effect of TNF-α on cementoblast autophagy has remained unclear. In this study, an elevated immunofluorescence signal of LC3B and autophagic vacuoles, autophagosomes and autolysosomes were detected under TNF-α stimulation in OCCM-30 cells. Autophagy-related genes and proteins, Beclin-1, LC3A and Atg-5, were significantly upregulated by TNF-α in a time- and concentration-dependent manner. During this process, the activity of Stat3 was dramatically enhanced and when the activity of Stat3 was blocked by either a specific chemical inhibitor or siRNA transfection before TNF-α stimulation, the TNF-α-induced upregulation of autophagy-related genes and proteins was strongly inhibited. Our results suggest that TNF-α induced autophagy in cementoblasts was dependent, or partially dependent on the activity of Stat3 signaling pathway. [ABSTRACT FROM AUTHOR]

In this work, a simple and novel ratiometric fluorescence method based on ROX-DNA-functionalized CdZnTeS quantum dots (QDs) was developed for the detection of dopamine (DA) and tyrosinase (TYR). A ratiometric fluorescent probe was constructed by binding phosphorothioate DNA to the metal ions of QDs, which is a modification-free and low-cost method. DA was easily oxidized to DA quinone under the catalysis of TYR by dissolved O2, which effectively quenched the fluorescence of the QDs. Strong linear correlations were achieved for TYR in the range of 10.0–100.0 ng mL−1 and for DA in the range of 10.0–1000.0 nM. The limit of detection was estimated to be as low as 1.05 ng mL−1 for TYR and 1.93 nM for DA. Moreover, various colors were displayed in the course of detection, which could be observed by the naked eye. Therefore, an on-site and sensitive fluorescence method for the visual detection of DA and TYR can be developed. In addition, the findings revealed the potential applicability of the ratiometric fluorescent probe for the detection of DA and TYR in human serum. This ratiometric fluorescence method is not only sensitive and selective but also rapid and convenient for the detection of the analytes without sophisticated instrumentation. [ABSTRACT FROM AUTHOR]

The uncertainties of China's gross primary productivity ( GPP) estimates by global data-oriented products and ecosystem models justify a development of high-resolution data-oriented GPP dataset over China. We applied a machine learning algorithm developing a new GPP dataset for China with 0.1° spatial resolution and monthly temporal frequency based on eddy flux measurements from 40 sites in China and surrounding countries, most of which have not been explored in previous global GPP datasets. According to our estimates, mean annual GPP over China is 6.62 ± 0.23 PgC/year during 1982-2015 with a clear gradient from southeast to northwest. The trend of GPP estimated by this study (0.020 ± 0.002 PgC/year2 from 1982 to 2015) is almost two times of that estimated by the previous global dataset. The GPP increment is widely spread with 60% area showing significant increasing trend ( p < .05), except for Inner Mongolia. Most ecosystem models overestimated the GPP magnitudes but underestimated the temporal trend of GPP. The monsoon affected eastern China, in particular the area surrounding Qinling Mountain, seems having larger contribution to interannual variability ( IAV) of China's GPP than the semiarid northwestern China and Tibetan Plateau. At country scale, temperature is the dominant climatic driver for IAV of GPP. The area where IAV of GPP dominated by temperature is about 42%, while precipitation and solar radiation dominate 31% and 27% respectively over semiarid area and cold-wet area. Such spatial pattern was generally consistent with global GPP dataset, except over the Tibetan Plateau and northeastern forests, but not captured by most ecosystem models, highlighting future research needs to improve the modeling of ecosystem response to climate variations. [ABSTRACT FROM AUTHOR]

It is important to accurately evaluate ecosystem respiration (RE) in the alpine grasslands of the Tibetan Plateau and the temperate grasslands of the Inner Mongolian Plateau, as it serves as a sensitivity indicator of regional and global carbon cycles. Here, we combined flux measurements taken between 2003 and 2013 from 16 grassland sites across northern China and the corresponding MODIS land surface temperature (LST), enhanced vegetation index (EVI), and land surface water index (LSWI) to build a satellite-based model to estimate RE at a regional scale. First, the dependencies of both spatial and temporal variations of RE on these biotic and climatic factors were examined explicitly. We found that plant productivity and moisture, but not temperature, can best explain the spatial pattern of RE in northern China's grasslands; while temperature plays a major role in regulating the temporal variability of RE in the alpine grasslands, and moisture is equally as important as temperature in the temperate grasslands. However, the moisture effect on RE and the explicit representation of spatial variation process are often lacking in most of the existing satellite-based RE models. On this basis, we developed a model by comprehensively considering moisture, temperature, and productivity effects on both temporal and spatial processes of RE, and then, we evaluated the model performance. Our results showed that the model well explained the observed RE in both the alpine (R2 = 0.79, RMSE = 0.77 g C m-2 day-1) and temperate grasslands (R2 = 0.75, RMSE = 0.60 g C m-2 day-1). The inclusion of the LSWI as the water-limiting factor substantially improved the model performance in arid and semi-arid ecosystems, and the spatialized basal respiration rate as an indicator for spatial variation largely determined the regional pattern of RE. Finally, the model accurately reproduced the seasonal and inter-annual variations and spatial variability of RE, and it avoided overestimating RE in water-limited regions compared to the popular process-based model. These findings provide a better understanding of the biotic and climatic controls over spatiotemporal patterns of RE for two typical grasslands and a new alternative up-scaling method for large-scale RE evaluation in grassland ecosystems. [ABSTRACT FROM AUTHOR]

Objectives Root resorption is a common phenomenon presented in periodontitis and orthodontic treatment, both of which are accompanied by an elevated TNF-α expression level in the periodontal tissues. Previously, we proved that TNF-α showed an inhibitory effect on cementoblast differentiation, mineralization and proliferation. However, the effect of TNF-α on Runx2 and osteoprotegerin ( OPG) expression remains undetermined. This study aimed to identify the influence of TNF-α on Runx2 and OPG expression in cementoblasts and to test whether BMP-2,-4,-6,-7 would affect TNF-α-regulated Runx2 and OPG. Materials and methods An immortalized murine cementoblast cell line OCCM-30 was used in this study. The expression of Runx2 and OPG were examined by qRT- PCR after stimulating cells with TNF-α. The role of signalling pathways, including MAPK, PI3K-Akt and NF-κB, were studied with the use of specific inhibitors. Cells were treated with TNF-α in combination with BMP-2,-4,-6 or -7, then the expression of Runx2 and OPG, the activity of MAPK and NF-κB pathways, and the proliferation ability were evaluated by qRT- PCR, Western blot and MTS assay respectively. Results TNF-α inhibited Runx2 and OPG mRNAs in OCCM-30 cells, and the inhibitory effects were further aggravated by blocking p38 MAPK or NF-κB pathway. TNF-α-inhibited Runx2 and OPG were up-regulated by BMP-4. The p38 MAPK and Erk1/2 pathways were further activated by the combined treatment of BMP-4 and TNF-α compared with TNF-α alone. Finally, the TNF-α-suppressed proliferation was not obviously affected by BMP-2,-4,-6 or -7. Conclusions TNF-α inhibited Runx2 and OPG in cementoblasts, and the p38 MAPK and NF-κB pathways acted in a negative-feedback way to attenuate the inhibitory effects. TNF-α-inhibited Runx2 and OPG could be effectively up-regulated by BMP-4; however, further investigations are needed to fully elaborate the underlying mechanisms. [ABSTRACT FROM AUTHOR]

Little is known about the impacts of climate change especially for cooling on NO emissions from alpine meadows on the Tibetan Plateau. Along a slope of Qilian mountains, China, we transferred intact soil cores covering different vegetation types (graminoid, shrub, forb, and sparse vegetation) downhill (warming) and uphill (cooling) across a 600-m elevation gradient to examine the responses of soil-atmosphere NO exchange rates to climate warming and cooling. NO fluxes were measured during two growing seasons from May to October in 2008 and 2009. The Tibetan alpine meadow acted as a net NO source at an average rate of 5.2 μg m h (ranging from 2.0 to 11.5 μg m h). In situ NO emission generally decreased with elevation increase except for sparse vegetation, but significant differences were only found between graminoid and other three vegetations in 2008 and between graminoid and shrub vegetation in 2009. Warming averagely increased mean NO fluxes by 219% (ranging from 126 to 287%) while cooling decreased it by 75% (ranging from 57 to 95%) across four vegetation types over the variation of soil temperature from 1.3 to 5.5 °C. However, opposite effects were also observed in some cases due to modification of variations in soil moisture. Soil temperature and moisture had a positive effect on NO fluxes and explained 48 and 26% of the variation in mean NO fluxes across the four vegetation types, respectively. No relationship was found between mean NO fluxes and aboveground biomass. Our results suggest that more NO-N would be released from soil in a warmer future and that less NO emission during cool and dry years is expected in the Tibetan alpine meadow. [ABSTRACT FROM AUTHOR]

Alpine wetland on the Qinghai-Tibetan Plateau holds the highest organic carbon density of plateau ecosystems and is among the most sensitive areas to climate change. Understanding CO exchange and its environmental forces in this specific ecosystem can benefit constraints of carbon budgets from site to global scale under future climate change. Here we investigated CO flux measurements from 2009 to 2013 in a wide-distributed alpine wetland, Kobresia littledalei-Blysmus sinocompressus swamp meadow, by eddy covariance (EC) on the central Tibetan Plateau. Results showed diurnal variation of net ecosystem CO exchange (NEE) was affected by photosynthetically active radiation (PAR), and this alpine swamp meadow had a high maximum ecosystem photosynthesis rate ( Amax) with 32.96 μmol CO m s. Nighttime ecosystem respiration (Re) rates were well associated with temperature, and average annual temperature sensitivity of Re (Q) was 3.2. Both temperature and relative humidity (RH) played key roles in regulations of seasonal NEE, and their interactive effect was only significant in GS, especially when soil temperature at 10 cm was above 6.3 °C. Our results suggested this alpine swamp meadow was a stable CO sink with an annual accumulation of −161.85 ± 28.02 g C m. However, response of annual Re was more sensitive than GPP to change of temperature and length of growing season (LOG), which implied that future climate warming likely to weaken the CO sink of this alpine swamp meadow. [ABSTRACT FROM AUTHOR]

The article presents a study aimed to evaluate the dentofacial anatomic traits related with lower incisor cancellous bone thickness (LICBT) and evaluate their contributions on the variation in LICBT. The study is undertaken through the use of a consecutive sample of cone beam computed tomography (CBCT) data taken in a university hospital of 252 eligible subjects for LICBT. The results of the study showed that the bony support of lower incisors is related with dentofacial traits.

The assumption of a linear relationship between temperature and phenophases may be misleading. Furthermore, a lack of understanding of the changes in temperature sensitivity of phenophases to changes in temperature strongly limits our ability to predict phenological change in response to climate change. We investigated the timing of seven phenophases of six alpine plant species to test the hypothesis of nonlinear responses in their temperature sensitivities to warming and cooling, using a reciprocal transplant experiment along a 3200-3800 m mountain slope gradient. Our results supported our hypothesis and showed that there were different thresholds in temperature sensitivity of phenophases to warming and cooling. Moreover, linear temperature sensitivity models significantly underestimated advances and delays of phenophases within the thresholds of temperature change. The nonlinear temperature sensitivity of phenophases is best explained by plastic and adaptive responses of phenophases to temperature change gradients. Therefore, our results suggest that the thresholds of temperature sensitivity for different species should be determined and that nonlinear models of temperature sensitivity may be essential to predict accurately phenological responses to climate change. [ABSTRACT FROM AUTHOR]

Aims: A lacking of understanding about cooling effects on methane (CH) fluxes and potential asymmetrical responses to warming and cooling causes uncertainty about climate change effects on the atmospheric CH concentration. We investigated CH fluxes in an alpine meadow on the Tibetan Plateau in response to climate warming and cooling. Methods: A 2-year reciprocal translocation experiment was implemented to simulate climate warming (i.e. downward translocation) and cooling (i.e. upward translocation) along an elevation gradient with four different vegetation types (at 3200, 3400, 3600 and 3800 m elevation) during the growing season (May to October) in 2008 and 2009. Results: Although the effects of warming and cooling varied depending on vegetation type, elevation and timescale (i.e., daily and seasonally), warming increased average seasonal CH uptake by 60 %, while cooling reduced it by 19 % across all vegetation types, based on a 1.3-5.1 °C difference in soil temperature at 20 cm depth. Soil temperature over the range of 4-10 °C explained 11-25 % of the variation in average seasonal CH fluxes, while there was no relationship with soil moisture over the range of 13-39 % and soil NH-N and NON content. Methane uptake was more sensitive to warming than to cooling. Conclusions: Because of warming and cooling spells in the alpine region, warming effects on CH uptake would be over-estimated by 64 % if cooling effects on it are not considered. Our findings suggest that asymmetrical responses of CH fluxes to warming and cooling should be taken into account when evaluating the effects of climate change on CH uptake in the alpine meadow on the Tibetan plateau. [ABSTRACT FROM AUTHOR]

Alpine ecosystems are among those biomes that are most vulnerable to climate change. Cushion plants are an important life form of alpine ecosystems and will likely play a critical role for the resilience of these habitats to climate change. We studied cushion size distribution and different measures of the compactness of cushions (biomass and rosette density, leaf area index) of the cushion plant, Androsace tapete along an elevational gradient from 4500 to 5200 m a.s.l. in the Nyainqentanglha Mountains of the central Tibetan Plateau. Cushion size distribution, total cover, and compactness of cushions varied substantially along the elevational gradient. At the driest site at low elevation we found the lowest total cushion cover, a particularly high proportion of very small cushions, and the most compact cushions (highest rosette and biomass densities, and leaf area index ( LAI) per cushion). Our results indicate that in the semi-arid Tibetan Plateau water availability is the more important climate factor than temperature affecting cushion plant traits and morphology. [ABSTRACT FROM AUTHOR]

The regression tree method is used to upscale evapotranspiration (ET) measurements at eddy-covariance (EC) towers to the grassland ecosystems over the Dryland East Asia (DEA). The regression tree model was driven by satellite and meteorology datasets, and explained 82% and 76% of the variations of ET observations in the calibration and validation datasets, respectively. The annual ET estimates ranged from 222.6 to 269.1 mm yr−1 over the DEA region with an average of 245.8 mm yr−1 from 1982 through 2009. Ecosystem ET showed decreased trends over 61% of the DEA region during this period, especially in most regions of Mongolia and eastern Inner Mongolia due to decreased precipitation. The increased ET occurred primarily in the western and southern DEA region. Over the entire study area, water balance (the difference between precipitation and ecosystem ET) decreased substantially during the summer and growing season. Precipitation reduction was an important cause for the severe water deficits. The drying trend occurring in the grassland ecosystems of the DEA region can exert profound impacts on a variety of terrestrial ecosystem processes and functions. [ABSTRACT FROM AUTHOR]

Questions How can we understand the limitations to plant growth at high altitudes? Our aim was to test the hypotheses that for alpine grasslands along a large altitudinal gradient in semi-arid regions, plant growth is mainly limited by drought at low altitudes but by low temperature at high altitudes, resulting in a unimodal pattern of biomass and productivity associated with an optimal combination of temperature and precipitation. Such knowledge is important to understanding the response of alpine ecosystems to climate change. Location We conducted a 5-yr livestock exclosure experiment along the south-facing slope of the Nyaiqentanglha Mountains, central Tibetan Plateau. Methods We measured above- and below-ground biomass, species richness, leaf δ13C and water potential, and related climate and soil variables across 42 fenced and unfenced quadrats near seven HOBO weather stations along the slope. The vegetation changed from alpine steppe-meadow at 4390-4500 m to alpine meadow at 4600-5210 m. Results Total above- and below-ground biomass across fenced and unfenced quadrats increased with increasing altitude up to 4950-5100 m, and then decreased above 5100 m. Altitudinal trends in leaf δ13C and water potential of dominant species also showed a unimodal pattern corresponding to that of vegetation biomass. Total above- and below-ground biomass as well as sedge above-ground biomass all showed a quadratic relationship with mean temperatures and the ratio of growing season precipitation ( GSP) to ≥5 °C accumulated temperature (AccT; R2 = 0.83−0.88, P < 0.001). In general, above- and below-ground biomass increased with increasing water availability when the GSP/AccT ratio was lower than the threshold level of 0.80-0.84, but decreased when the GSP/AccT ratio was higher than this threshold level. No significant relationship was found between residuals of above-ground biomass and species richness after removing the effects of climate factors on both stand variables. Conclusions The results support our hypotheses, further suggesting a threshold of water limitation that is consistent with the model prediction over the Tibetan Plateau. Species richness per se appears to weakly affect community-level productivity. The response of alpine grasslands to climate warming may vary with altitude because of altitudinal shifts in factors limiting plant growth. [ABSTRACT FROM AUTHOR]

Carbon dioxide fluxes of Kobresia humilis and Potentilla fruticosa shrub meadows, two typical ecosystems in the Qinghai-Tibet Plateau, were measured by eddy covariance technology and the data collected in August 2003 were employed to analyze the relations between carbon dioxide fluxes and environmental factors of the ecosystems. August is the time when the two ecosystems reach their peak leaf area indexes and stay stable, and also the period when the net carbon absorptions of Kobresia humilis and Potentilla fruticosa shrub meadows reach 56.2 g C·m−2 and 32.6 g C·m−2, with their highest daily carbon dioxide absorptions standing at 12.7 μmol·m−2·s−1 and 9.3 μmol·m−2·s−1, and their highest carbon discharges at 5.1 μmol·m−2·s−1 and 5.7 μmol·m−2·s−1, respectively. At the same photosynthetic photo flux densities (PPFD), the carbon dioxide-uptake rate of the Kobresia humilis meadow is higher than that of the Potentilla fruticosa shrub meadow; where the PPFD are higher than 1,200 μmol·m−2·s−1. The carbon dioxide uptake rates of the two ecosystems declined as air temperature increased, but the carbon dioxide uptake rate of the Kobresia humilis meadow decreased more quickly (−0.086) than that of the Potentilla fruticosa shrub meadow (−0.016). Soil moistures exert influence on the soil respirations and this varies with the vegetation type. The daily carbon dioxide absorptions of the ecosystems increase with increased diurnal temperature differences and higher diurnal temperature differences result in higher carbon dioxide exchanges. There exists a negative correlation between the vegetation albedos and the carbon dioxide fluxes. [ABSTRACT FROM AUTHOR]

Using the eddy covariance method, from 1 July 2003 to 30 June 2004, we conducted the observation and analysis of ecosystem CO2 flux in 3 types of alpine meadow vegetation (Kobresia humilis, Potentilla fruticosa shrub and Kobresia tibetica swamp meadows) on the Qinghai-Tibetan Plateau. The results show that the Kobresia humilis meadow, the shrub meadow and the swamp meadow's highest CO2 uptake rates are 16.78, 10.42 and 16.57 µmol·m-2·s-1 respectively, while their highest CO2 release rates are 8.22, 7.73 and 18.67 µmol·m-2·s-1 respectively. The Kobresia humilis meadow and shrub meadow's annual atmospheric uptakes are 282 g CO2/m² and 53 g CO2/m², respectively, while swamp meadow's annual atmospheric release is 478 g CO2/m². This proves that the Kobresia humilis meadow and the shrub meadow on the Qinghai-Tibetan Plateau have relatively low potential for CO2 uptake and release compared to C4 grasslands, a number of lowland grasslands, and forests. Moreover, swamp meadow has relatively high release potential. This, in turn, reveals clear differences in carbon source/sink between different types of vegetation in the Qinghai-Tibetan Plateau alpine meadow ecosystem. These differences are mainly brought by differences in the vegetations' photosynthetic capacity and soil respiration. [ABSTRACT FROM AUTHOR]

While a number of machine learning (ML) models have been used to estimate RE, systematic evaluation and comparison of these models are still limited. In this study, we developed three traditional ML models and a deep learning (DL) model, stacked autoencoders (SAE), to estimate RE in northern China's grasslands. The four models were trained with two strategies: training for all of northern China's grasslands and separate training for the alpine and temperate grasslands. Our results showed that all four ML models estimated RE in northern China's grasslands fairly well, while the SAE model performed best (R2 = 0.858, RMSE = 0.472 gC m−2 d−1, MAE = 0.304 gC m−2 d−1). Models trained with the two strategies had almost identical performances. The enhanced vegetation index and soil organic carbon density (SOCD) were the two most important environmental variables for estimating RE in the grasslands of northern China. Air temperature (Ta) was more important than the growing season land surface water index (LSWI) in the alpine grasslands, while the LSWI was more important than Ta in the temperate grasslands. These findings may promote the application of DL models and the inclusion of SOCD for RE estimates with increased accuracy. [ABSTRACT FROM AUTHOR]

Changes in day (maximum temperature, TMAX) and night temperature (minimum temperature, TMIN) in the preseason (e.g., winter and spring) may have opposite effects on early phenophases (e.g., leafing and flowering) due to changing requirements of chilling accumulations (CAC) and heating accumulations (HAC), which could cause advance, delay or no change in early phenophases. However, their relative effects on phenology are largely unexplored, especially on the Tibetan Plateau. Here, observations were performed using a warming and cooling experiment in situ through reciprocal transplantation (2008–2010) on the Tibetan Plateau. We found that winter minimum temperature (TMIN) warming significantly delayed mean early phenophases by 8.60 d/°C, but winter maximum temperature (TMAX) warming advanced them by 12.06 d/°C across six common species. Thus, winter mean temperature warming resulted in a net advance of 3.46 d/°C in early phenophases. In contrast, winter TMIN cooling, on average, significantly advanced early phenophases by 5.12 d/°C, but winter TMAX cooling delayed them by 7.40 d/°C across six common species, resulting in a net delay of 2.28 d/°C for winter mean temperature cooling. The opposing effects of TMAX and TMIN warming on the early phenophases may be mainly caused by decreased CAC due to TMIN warming (5.29 times greater than TMAX) and increased HAC due to TMAX warming (3.25 times greater than TMIN), and similar processes apply to TMAX and TMIN cooling. Therefore, our study provides another insight into why some plant phenophases remain unchanged or delayed under climate change. [ABSTRACT FROM AUTHOR]

A fluorometric method is described for the determination of the tumor biomarker mucin 1 (MUC1). It is based on signal amplification of the hybridization chain reaction (HCR), and the interaction between a luminescent ruthenium(II) complex and CdZnTeS quantum dots (QDs). If MUC1 bind to the biotin-labeled aptamer, it will initiate HCR with hairpins H1 and H2 to form a long-range dsDNA. The long nucleic acid chains are then linked on the surface of streptavidin-modified magnetic microparticles (MMPs) through streptavidin-biotin interaction. The luminescent ruthenium(II) complex is then embedded in the long dsDNA linked to the MMPs. Hence, there is little Ru complex in the supernatant after magnetic separation, and the fluorescence of the CdZnTeS QDs (best measured at excitation/emission wavelengths of 350/530 nm) is only slightly quenched. In the absence of target, the fluorescence of the CdZnTeS QDs is strongly quenched. Fluorescence increases linearly in the 0.2–100 ng·mL−1 MUC1 concentration range, and the LOD is 0.13 ng·mL−1 (at S/N = 3). The method was applied to the determination of MUC1 in spiked human serum samples. Graphical abstract A fluorometric turn-on aptasensor for mucin 1 is described that is based on the interaction between a Ru(II) complex and quantum dots (QDs). The detection system includes biotin-labeled aptamer-H0, hairpins H1 and H2, streptavidin-modified magnetic microparticles (MMPs), Ru(bpy)2(dppx)2+ and CdZnTeS QDs. [ABSTRACT FROM AUTHOR]