Synergistic antitumor activity between HER2 antibody-drug conjugate and chemotherapy for treating advanced colorectal cancer.

Colorectal cancer (CRC) is the third most common cancer associated with a poor prognosis. Effective targeted therapy alone or in combination for treating advanced CRC remains to be a major clinical challenge. Here, we propose the therapeutic efficacy and molecular mechanism underlying RC48, a FDA-approved anti-HER2 antibody conjugate via a cleavable linker to the microtubule inhibitor monomethyl auristatin E (MMAE), either alone or in combination with gemcitabine (GEM) in various models of HER2-positive advanced CRC. Our findings demonstrated that HER2 was widely expressed and located on the plasma membrane of CRC patient specimens, PDX xenograft tumors and cell lines. It confirmed that RC48 alone significantly targeted and eradicated HER2 positive CRC tumor in these models. Moreover, we screened a panel of FDA-approved first-line chemotherapy drugs in vitro. We found that GEM exhibited stronger antiproliferative activity compared to the other first-line anti-cancer agents. Furthermore, combination therapy of RC48 and GEM significantly showed synergetic antitumor activity in vitro and in vivo. To gain further mechanistic insights into the combination therapy, we performed RNA-seq analysis. The results revealed that combination treatment of RC48 and GEM regulated multiple signaling pathways, such as PI3K-AKT, MAPK, p53, Foxo, apoptosis, cell cycle and cell senescence, etc., to exert its antitumor activity in CRC cells. Collectively, these preclinical findings demonstrated that RC48 alone or combinational therapy exerted promising antitumor activity, and meriting the preclinical framework for combinational therapy of anti-HER2 drug conjugate drug and chemotherapy drugs for HER2-positive patients with advanced CRC.

Farrerol Alleviates Cerebral Ischemia-Reperfusion Injury by Promoting Neuronal Survival and Reducing Neuroinflammation.

Ischemia-reperfusion (I/R) injury is a key influencing factor in the outcome of stroke. Inflammatory response, oxidative stress, and neuronal apoptosis are among the main factors that affect the progression of I/R injury. Farrerol (FAR) is a natural compound that can effectively inhibit the inflammatory response and oxidative stress. However, the role of FAR in cerebral I/R injury remains unknown. In this study, we found that FAR reduced brain injury and neuronal viability after cerebral I/R injury. Meanwhile, administration of FAR also reduced the inflammatory response of microglia after brain injury. Mechanistically, FAR treatment directly reduced neuronal death after oxygen glucose deprivation/re-oxygenation (OGD/R) through enhancing cAMP-response element binding protein (CREB) activation to increase the expression of downstream neurotrophic factors and anti-apoptotic genes. Moreover, FAR decreased the activation of nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways, inhibited microglia activation, and reduced the production of inflammatory cytokines in microglia after OGD/R treatment or LPS stimulation. The compromised inflammatory response by FAR directly promoted the survival of neurons after OGD/R. In conclusion, FAR exerted a protective effect on cerebral I/R injury by directly decreasing neuronal death through upregulating CREB expression and attenuating neuroinflammation. Therefore, FAR could be a potentially effective drug for the treatment of cerebral I/R injury.

The adverse effects of vitrification on mouse embryo development and metabolic phenotype in offspring.

Embryo vitrification is a standard procedure in assisted reproductive technology. Previous studies have shown that frozen embryo transfer is associated with an elevated risk of adverse maternal and neonatal outcomes. This study aimed to explore the effects of mouse blastocyst vitrification on the phenotype of vitrified-warmed blastocysts, their intrauterine and postnatal development, and the long-term metabolic health of the derived offspring. The vitrified-warmed blastocysts (IVF + VT group) exhibited reduced mitochondrial activity, increased apoptotic levels, and decreased cell numbers when compared to the fresh blastocysts (IVF group). Implantation rates, live pup rates, and crown-rump length at E18.5 were not different between the two groups. However, there was a significant decrease in fetal weight and fetal/placental weight ratio in the IVF + VT group. Furthermore, the offspring of the IVF + VT group at an age of 36 weeks had reduced whole energy consumption, impaired glucose and lipid metabolism when compared with the IVF group. Notably, RNA-seq results unveiled disturbed hepatic gene expression in the offspring from vitrified-warmed blastocysts. This study revealed the short-term negative impacts of vitrification on embryo and fetal development and the long-term influence on glucose and lipid metabolism that persist from the prenatal stage into adulthood in mice.

Association between increased C-reactive protein and cardiovascular disease among patients with rectal cancer.

Purpose: This study aimed to investigate the association between increased C-reactive protein (CRP) and cardiovascular disease (CVD) in individuals with rectal cancer, as well as to understand the effect of chemotherapy for cancer on increasing CRP and its underlying mechanisms. Patients and methods: From January 1, 2010 to December 31, 2020, individuals with rectal cancer were evaluated at the First Affiliated Hospital of Gannan Medical University. Then, in patients with rectal cancer, the relationship between increased CRP and CVD attributes was summarized, and the impact of chemotherapy on CRP levels was qualitatively assessed. For further investigation into potential regulatory mechanisms of CRP, differentially expressed genes (DEGs), GO and KEGG enrichment analyses were conducted. Results: A total of 827 individuals were included in the study, including 175 with CVD (21.16%) and 652 without CVD. A significant association between increased CRP and CVD events was observed in rectal cancer patients (p < 0.01), and it significantly improved the classification performance of the CVD predictive model in the AUC (0.724 vs 0.707) and NRI (0.069, 95% CI 0.05-0.14). Furthermore, a comparison of CRP levels before and after chemotherapy revealed a significant increase among rectal cancers post-treatment (p < 0.001). Analysis of differentially expressed genes and co-expression indicated that 96 DEGs were involved in the pathophysiology of increased CRP after chemotherapy, and three hub genes were implicated in atherosclerotic susceptibility. Conclusion: In conclusion, our findings indicated that increased CRP levels following chemotherapy profoundly impacted CVD events in individuals with rectal cancer, and may be beneficial in promoting CVD prediction in clinical practice.

Biomimetic Surface Engineering to Modulate the Coffee-Ring Effect for Amyloid-ß Detection in Rat Brains.

Surface engineering of nanoparticles has been widely used in biosensing and assays, where sensitivity was mainly limited by plasmonic colour change or electrochemical responses. Here, we report a novel biomimetic sensing strategy involving protein-modified gold nanoparticles (AuNPs), where the modulation strategy was inspired by gastropods in inhibition of coffee-ring effects in their trail-followings. The so-called coffee-ring effect presents the molecular behaviour of AuNPs to a macroscopic ring through aggregation, and thus greatly improves sensitivity. The assay relies upon the different assembly patterns of AuNPs against analytes, resulting in the formation or suppression of coffee-ring effects by the different surface engineering of AuNPs by proteins and peptides. The mechanism of the coffee-ring formation process is examined through experimental characterizations and computational simulations. A practical coffee-ring effect assay is developed for a proof-of-concept target, amyloid ß (1-42), which is a typical biomarker of Alzheimer's disease. A novel quasi-titrimetric protocol is constructed for quantitative determination of the target molecule. The assay shows excellent selectivity and sensitivity for the amyloid ß monomer, with a low detection limit of 20 pM. Combined with a fluorescent staining technique, the assay is designed as a smart sensor for amyloid ß detection and fibrillation evaluation in rat cerebrospinal fluids, which is a potential point-of-care test for Alzheimer's disease. Connections between amyloid fibrillation and different courses of brain ischaemia are also studied, with improved sensitivity, lower sample volumes that are required, convenience for rapid detection, and point-of-care testing.

Prognostic biomarker SYK and its correlation with immune infiltrates in glioma.

The tumor microenvironment (TME) provides excellent conditions for the development of glioma. The present study sought to identify the prognostic factors of glioma that could be used to improve the prognosis of patients with this disease. In the present study, Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) and Estimation of Stromal and Immune cells in Malignant Tumor tissues using Expression data calculations were employed to estimate the ratio of tumor-infiltrating immune cells and the quantity of immune and stromal components in 698 glioma cases from the Cancer Genome Atlas database. In addition, certain differentially expressed genes were studied by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses and single genes associated with prognosis were identified by protein-protein interaction (PPI) network and Cox combined analysis. The immune and stromal scores of the TME were significantly associated with glioma patient survival. By using the PPI network and Cox regression analyses, spleen tyrosine kinase (SYK) was eventually identified as the best prognostic factor for patients with glioma. In addition, Gene Set Enrichment Analysis and CIBERSORT analyses were employed. The former indicated that the high-expression SYK group genes were mainly enriched in immune-related activities. The latter revealed that SYK expression was positively associated with T cell cluster of differentiation 4 memory resting and monocytes. The aforementioned experimental analyses provided the theoretical basis for the biological prediction of SYK. The data indicated that SYK contributed to immune predictors in patients with glioma by facilitating the shift of the TME from immune dominance to metabolic activity. Finally, reverse transcription-quantitative PCR and western blotting were used to verify the single gene expression in glioma cells. This may provide prognostic value for the treatment of glioma.

Aberrant expression of miR-33a-3p/IGF2 in postmenopausal osteoporosis patients and its role and mechanism in osteoporosis.

BACKGROUND: Postmenopausal osteoporosis (PMOP), the most frequent bone-related disease, is characterized by bone loss and fragile fractures, which is related to low bone density (BMD). This study aimed to illustrate the expression and mechanism of miR-33a-3p in osteoporosis. METHODS: TargetScan and luciferase reporter assay were applied for verifying the relevance between miR-33a-3p and IGF2. Levels of miR-33a-3p, IGF2, Runx2, ALP and Osterix were checked using RT-qPCR and western blotting. hBMSCs proliferation, apoptosis and ALP activity were analyzed by MTT, flow cytometry (FCM) analysis and ALP detection kit, respectively. Moreover, the calcification of cells was assessed using Alizarin Red S staining. The average BMD was evaluated by dual-energy X-ray absorptiometry (DEXA) assay. RESULTS: IGF2 was a target of miR-33a-3p. The level of miR-33a-3p was substantially higher and IGF2 expression was memorably lower in the serum of osteoporosis patients than that in healthy volunteers. Our results also pointed out that miR-33a-3p was reduced and IGF2 expression was enhanced during osteogenic differentiation. We concluded that miR-33a-3p negatively regulated the level of IGF2 in hBMSCs. Besides, miR-33a-3p mimic inhibited the osteogenic differentiation of hBMSCs via inhibiting the level of Runx2, ALP and Osterix and decreasing ALP activity. IGF2 plasmid dramatically reversed the influence of miR-33a-3p mimic on IGF2 expression, hBMSCs proliferation and apoptosis, and osteogenic differentiation of hBMSCs. CONCLUSION: miR-33a-3p affected osteogenic differentiation of hBMSCs by targeting IGF2, indicating a potential use of miR-33a-3p as plasma biomarker and therapeutic target for postmenopausal osteoporosis.

Techniques and graft materials for repairing peripheral nerve defects.

Peripheral nerve defects refer to damage or destruction occurring in the peripheral nervous system, typically affecting the limbs and face. The current primary approaches to address peripheral nerve defects involve the utilization of autologous nerve transplants or the transplantation of artificial material. Nevertheless, these methods possess certain limitations, such as inadequate availability of donor nerve or unsatisfactory regenerative outcomes post-transplantation. Biomaterials have been extensively studied as an alternative approach to promote the repair of peripheral neve defects. These biomaterials include both natural and synthetic materials. Natural materials consist of collagen, chitosan, and silk, while synthetic materials consist of polyurethane, polylactic acid, and polycaprolactone. Recently, several new neural repair technologies have also been developed, such as nerve regeneration bridging technology, electrical stimulation technology, and stem cell therapy technology. Overall, biomaterials and new neural repair technologies provide new methods and opportunities for repairing peripheral nerve defects. However, these methods still require further research and development to enhance their effectiveness and feasibility.

Primary balloon angioplasty for chronic occlusion of intracranial internal carotid artery: A case report.

Chronic occlusion of large intracranial arteries is the main cause of ischemic stroke in China. Patients with symptomatic intracranial artery occlusion and hemodynamic impairment are at high risk of recurrent stroke. Chronic occlusion of the intracranial segment of the internal carotid artery is a common type of intracranial artery occlusion. Medical management is regarded as the standard treatment for this disease. With the development of endovascular treatment, some patients with chronic cerebral artery occlusion have achieved satisfactory results with endovascular therapy. We reported a patient with symptomatic chronic occlusion of the ophthalmic segment of the internal carotid artery. Simple balloon angioplasty was performed, and the occluded ophthalmic segment of the internal carotid artery was successfully recanalized without perioperative complications. At 4 months follow-up, the internal carotid artery remained patent and perfusion of the right cerebral hemisphere improved dramatically. In addition, we briefly reviewed the relevant literature.

Rapid Discovery of Efficient Long-Wavelength Emission Garnet:Cr NIR Phosphors via Multi-Objective Optimization.

High-efficiency long-wavelength emission near-infrared (NIR) phosphors are the key to next-generation LED light sources. However, high-efficiency phosphors usually exhibit narrow-band emission at shorter wavelengths due to the crystal field intensity. In this paper, we utilize multi-objective optimization to discover the NIR phosphor Gd3Mg0.5Al1.5Ga2.5Ge0.5O12:0.04Cr3+. It exhibits a broadband NIR emission from 650 to 1100 nm peaking at 763 nm, with a full width at half maximum (FWHM) of 150 nm, an internal quantum efficiency (IQE)/external quantum efficiency (EQE) of 90%/53.1%, and good thermal stability (85.3% @ 150 °C). The packaging results show that ∼53.2 mW of output power is achieved at 915 mW input power, which suggests promising applications for NIR pc-LED. Our approach is based on the data of emission wavelength (WL) and IQE for garnet:Cr NIR phosphors to construct machine learning models. An active learning strategy is used to make tradeoffs between WL and IQE, and we are able to find the targeted phosphor after only four iterations of synthesis and characterization.

Low-molecular-weight fucoidan bidirectionally regulates lipid uptake and cholesterol efflux through the p38 MAPK phosphorylation.

Atherosclerosis (AS) is the pathological basis of many cardiovascular and cerebrovascular diseases, in which macrophage-derived foam cells are the critical step and a typical pathological feature of early atherosclerosis. We previously confirmed that low-molecular-weight fucoidan (LMWF) had a good anti-AS effect, but the mechanism is still unclear. Here with aim to investigate the inhibitory effect of LMWF on foam cells and its molecular mechanism. Oil red O staining showed that LMWF effectively alleviated lipid accumulation and the formation of foam cells. Flow cytometry detection showed that LMWF promoted foam cells apoptosis. In addition, immunofluorescence showed that LMWF inhibited macrophage scavenger receptor A1 (SR-A1)-mediated lipid uptake and promoted ATP-binding cassette transporter A1 (ABCA1)-mediated cholesterol outflow. Western blot showed that LMWF downregulated SR-A1 protein expression and upregulated ABCA1 protein expression by inhibiting p38 mitogen activated protein kinase (p38MAPK) phosphorylation. Moreover, the mRNA transcriptions of Stat1, Elk-1, and Myc were downregulated when treated with LMWF. It concluded that, LMWF achieved bidirectional regulation of SR-A1 and ABCA1, then prevented the formation of foam cells, finally ameliorated the development of AS.

Ultrasensitive Frequency Shifting of Dielectric Mie Resonance near Metallic Substrate.

Dielectric resonators on metallic surface can enhance far-field scattering and boost near-field response having promising applications in nonlinear optics and reflection-type devices. However, the dependence of gap size between dielectric resonator and metallic surface on Mie resonant frequency is complex and desires a comprehensive physical interpretation. Here, we systematically study the effect of metallic substrate on the magnetic dipole (MD) resonant frequency at X-band by placing a high permittivity CaTiO3 ceramic block on metallic substrate and regulating their gap size. The simulated and experimental results show that there are two physical mechanisms to codetermine the metallic substrate-induced MD frequency. The greatly enhanced electric field pair in the gap and the coupling of MD resonance with its mirror image are decisive for small and large gaps, respectively, making the MD resonant frequency present an exponential blue shift first and then a slight red shift with increasing gap size. Further, we use the two mechanisms to explain different frequency shifting properties of ceramic sphere near metallic substrate. Finally, taking advantage of the sharp frequency shifting to small gaps, the ceramic block is demonstrated to accurately estimate the thickness or permittivity of thin film on metallic substrate through a governing equation derived from the method of symbolic regression. We believe that our study will help to understand the resonant frequency shifting for dielectric particle near metallic substrate and give some prototypes of ultrasensitive detectors.

Multiobjective Machine Learning-Assisted Discovery of a Novel Cyan-Green Garnet: Ce Phosphors with Excellent Thermal Stability.

Ce-doped garnet phosphors play an important role in the white light-emitting diode (LED) family. In the past years, a lot of trial-and-error experiments guided by experience to discover phosphors suitable for white LEDs have been presented. The working temperature of phosphors may reach 200 °C in white LEDs, and so, the exploration of phosphors with excellent thermal stability at the desired wavelength continues to be a challenge. In the present study, to discover novel cyan-green garnet:Ce phosphors, wavelength and thermal stability machine learning models were built by constructing reasonable features. Among the 171,636 compounds with garnet structures predicted by our models, 25 samples were selected for preparation and characterization by multiobjective optimization based on active learning. Lu1.5Sr1.5Al3.5Si1.5O12:Ce performed the best with excellent thermal stability (≥60% emission intensity was retained at 640 K) and exhibited emission peaks of about 505 nm, and it is a very promising phosphor for future applications, especially in high-temperature operating environments.

Peptide-based 68Ga-PET radiotracer for imaging CD133 expression in colorectal cancer.

OBJECTIVE: CD133 is a demonstrated cancer stem cell marker. A small peptide LS7, screened by a phage display technique, was identified to specifically target CD133. The purpose of this study was to develop a novel and specific peptide-based PET imaging agent for CD133 imaging in colorectal cancer. METHODS: The peptide LS7 was conjugated with 1,4,7,20-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) and radiolabeled with 68Ga. The cellular uptake was assessed in vitro. In vivo small-animal PET/CT and ex vivo biodistribution evaluations were performed in mice bearing CD133-positive HCT116 and Lovo cell-derived tumors as well as CD133-negative DLD1 cell-derived tumors. Nonspecific uptake of the tracer in HCT116 cell-derived tumor cells and tumor models was determined by coincubation or coinjection with an excess of unlabeled DOTA-LS7 along with radiolabeled tracers. RESULTS: 68Ga-DOTA-LS7 was produced with 80.0% yield and the radiochemical purity was greater than 95.0%. In vitro, 68Ga-DOTA-LS7 was selectively taken up by HCT116 and Lovo cells but not by DLD1 cells. Small-animal PET/CT clearly revealed deposition of 68Ga-DOTA-LS7 in HCT116 and Lovo cell-derived tumors with excellent contrast. Biodistribution demonstrated that the tumor uptakes were 2.24 ± 0.16, 1.76 ± 0.42, and 0.69 ± 0.28% ID/g in HCT116, Lovo and DLD1 cell-derived tumors, respectively, at 90 min post-injection. Uptake of 68Ga-DOTA-LS7 in HCT116 tumors was significantly inhibited by coinjection of excess DOTA-LS7. CONCLUSION: Rapid tumor CD133 detection and selectivity were demonstrated in vitro and in vivo with PET using the specific CD133 binding peptide 68Ga-DOTA-LS7. A robust correlation was detected in vivo between tumor signals from mouse xenograft models with different cell lines and CD133 expression. The favorable characteristics of 68Ga-DOTA-LS7, such as convenient synthesis and specific uptake, warrant its further investigation for CD133 expression imaging.

Concurrent ductal adenocarcinoma, pseudocyst, and neuroendocrine tumor of the pancreas: A case report.

INTRODUCTION: Pancreatic pseudocyst is one of the most common cystic lesions. It always occurs following pancreatitis and is rarely found in combination with pancreatic adenocarcinoma. The coexistence of exocrine and neuroendocrine tumors of the pancreas is also infrequent. We herein report a case of simultaneous occurrence of a pancreatic ductal adenocarcinoma (PDAC), pseudocyst, and neuroendocrine tumor (NET), showing a "side-by-side pattern." PATIENT CONCERN: A 74-year-old man was hospitalized for epigastric pain and poor appetite. He had no history of pancreatitis, alcohol consumption, or smoking. DIAGNOSIS AND INTERVENTION: Abdominal enhanced computed tomography and magnetic resonance imaging revealed a 15 × 8 cm cystic lesion with poor enhancement located in the tail of the pancreas. The distal aspect of the main pancreatic duct was dilated. The pancreatic parenchyma adjacent to the cystic lesion showed slightly heterogeneous enhancement on computed tomography and magnetic resonance imaging. Laboratory examination showed an elevated carbohydrate antigen 19-9 serum level. The patient was preoperatively diagnosed with intraductal papillary mucinous neoplasm and subsequently underwent laparotomy. During the operation, a hard white tumor measuring about 4 × 3 cm was palpated adjacent to the cystic lesion on the duodenal side, and a 0.6-cm nodule was simultaneously found in the pancreatic tail. Therefore, total pancreatectomy and splenectomy were performed. Histopathological examination showed that the tumor was PDAC with an adjacent pseudocyst, and the small nodule was suggestive of a NET. OUTCOMES: The patient survived without recurrence or metastasis in the follow-up visit 10 months after the operation and adjuvant chemotherapy. CONCLUSIONS: The concomitant occurrence of a PDAC, pseudocyst, and NET has not been previously reported. We suggest that if a pancreatic cyst is found, the coincidental occurrence of a malignant tumor should be considered, especially if the carbohydrate antigen 19-9 level is increased. Additionally, dilation of the pancreatic duct may be a diagnostic clue. Furthermore, the simultaneous occurrence of pancreatic endocrine and exocrine tumors is very uncommon. Preoperative diagnosis becomes difficult because of the lack of specific symptoms and radiological features.

Carbon emissions from energy consumption in China: Its measurement and driving factors.

To address climate change effectively, it is essential to quantify CO2 emissions and the driving factors in high-energy-consuming countries. China is the top CO2-emitting country; moreover, there is a lack of comprehensive analytical studies on quantifying the contributions of key drivers to high-energy-consuming countries' CO2 emissions. Therefore, based on data of China's energy consumption from 2005 to 2016, this paper combines the extended Kaya identity with the logarithmic mean Divisia index (LMDI) decomposition method to construct an optimized carbon emission decomposition model. Carbon emission and carbon emission intensity are measured and decomposed. Then, the results of the decomposition are discussed, and the effects of various drivers on carbon emissions from energy consumption in China are analysed. Furthermore, we demonstrate real applications of decomposition analysis in policy-making using examples from China and present some ideas to reduce CO2. The results show that from 2005 to 2016, China's total carbon emissions accounted for nearly one-third of the world's total carbon emissions, and the intensity of carbon emissions in China was generally higher than that of worldwide. The rapid development of economy and acceleration of urbanization are not conducive to reduction of carbon emissions. Reducing the intensity of energy consumption, adjusting the internal structure of the industry and perfecting the economic policy system should be important means used to promote the development of China's low-carbon economy in the future.

Research on the ecological efficiency of the Yangtze River Delta region in China from the perspective of sustainable development of the economy-energy-environment (3E) system.

Balancing the relationship between economic development, energy utilization, and environmental protection has become an important task in China's Strip Planning and Construction. This article takes the annual panel data from 2005 to 2015 as the research object firmly grasps the research basis of the Economy-Energy-Environment (3E) System, and focuses on building a new research framework from both internal and external perspectives of the eco-efficiency index to achieve the exploratory research on regional ecological efficiency changes and influencing factors. First of all, it uses super-efficient slacks-based measure (SBM) model which introduces undesired outputs to measure eco-efficiency at different levels. Then, it applies Malmquist index to calculate total factor productivity and structural efficiencies. Finally, it selects six indicators and uses the STIRPAT regression model to analyze external factors. The results indicate that (1) the overall ecological efficiency is effective and maintaining a good momentum of development. Among all the cities and provinces, Shanghai and Zhejiang provinces play the role of "stabilizers," while Jiangsu and Anhui provinces act as "accelerators." (2) All 41 prefecture-level cities can be divided into four different types, i.e., "high-high", "low-high", "low-low," and "high-low" cities, and there is an obvious phenomenon of spatial clustering; (3) pure technical efficiency and scale efficiency is the core driving force for the improvement of ecological efficiency. (4) Anhui and Jiangsu provinces show a U-shaped relationship, while Zhejiang province shows an inverted U-shaped relationship. Graphical abstract The structure of introduction-body paragraphs-conclusion carbon.

Ecological efficiency in China and its influencing factors-a super-efficient SBM metafrontier-Malmquist-Tobit model study.

Ecological problem is one of the core issues that restrain China's economic development at present, and it is urgently needed to be solved properly and effectively. Based on panel data from 30 regions, this paper uses a super efficiency slack-based measure (SBM) model that introduces the undesirable output to calculate the ecological efficiency, and then uses traditional and metafrontier-Malmquist index method to study regional change trends and technology gap ratios (TGRs). Finally, the Tobit regression and principal component analysis methods are used to analysis the main factors affecting eco-efficiency and impact degree. The results show that about 60% of China's provinces have effective eco-efficiency, and the overall ecological efficiency of China is at the superior middling level, but there is a serious imbalance among different provinces and regions. Ecological efficiency has an obvious spatial cluster effect. There are differences among regional TGR values. Most regions show a downward trend and the phenomenon of focusing on economic development at the expense of ecological protection still exists. Expansion of opening to the outside, increases in R&D spending, and improvement of population urbanization rate have positive effects on eco-efficiency. Blind economic expansion, increases of industrial structure, and proportion of energy consumption have negative effects on eco-efficiency.

[Effects of UV Radiation on the Coagulation Process of Kaolin and Involved Mechanisms].

Kaolin commonly exists in water,and it has an important impact on the water treatment processes and contaminants'migration and transformation.In this study,PAC was used as flocculating agent to systematically investigate the effects of UV radiation on the coagulation process of kaolin by jar test.The results showed that under neutral and acidic conditions,UV radiation could promote the coagulation process of kaolin suspension.When the solution pH,coagulant dosage and irradiation time were 7.0,30 mg·L-1 and 2.0 h,respectively,the kaolin remove rate of effluent after coagulation increased from 81.05% to 93.90% by using UV radiation.This might be related to the decrease of-OH stretching vibration absorption peak and the enhancement of Si-O stretching vibration absorption peak and Si-O bending vibration absorption peak after UV radiation,so that the number of the active spot (-OH) on kaolin surface declined.These changes might lead to decrease of the negative charge on kaolin surface,which promoted kaolin suspension to precipitate in coagulation process.However,under alkaline conditions,its settlement performance was slightly lower than the water samples without ultraviolet radiation treatment.