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1.
J Am Chem Soc ; 146(12): 8598-8606, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38465613

RESUMEN

This study outlines the preparation and characterization of a unique superlattice composed of indium oxide (In2O3) vertex-truncated nano-octahedra, along with an exploration of its response to high-pressure conditions. Transmission electron microscopy and scanning transmission electron microscopy were employed to determine the average circumradius (15.2 nm) of these vertex-truncated building blocks and their planar superstructure. The resilience and response of the superlattice to pressure variations, peaking at 18.01 GPa, were examined using synchrotron-based wide-angle X-ray scattering (WAXS) and small-angle X-ray scattering (SAXS) techniques. The WAXS data revealed no phase transitions, reinforcing the stability of the 2D superlattice composed of random layers in alignment with a p31m planar symmetry as discerned by SAXS. Notably, the SAXS data also unveiled a pressure-induced, irreversible translation of octahedra and ligand interaction occurring within the random layer. Through our examination of these pressure-sensitive behaviors, we identified a distinctive translation model inherent to octahedra and observed modulation of the superlattice cell parameter induced by pressure. This research signifies a noteworthy advancement in deciphering the intricate behaviors of 2D superlattices under a high pressure.

2.
Environ Sci Technol ; 2024 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-39445385

RESUMEN

The nocturnal boundary layer (NBL) significantly influences the dispersion and fate of atmospheric species at night. Subtropical forests are crucial in carbon and water exchange between the biosphere and the atmosphere. However, the NBL characteristics and their impact on atmospheric species over these forests remain unknown. This study conducted vertical measurements of atmospheric species such as O3 and volatile organic compounds (VOCs), along with meteorological variables, over a national forest reserve in Southern China. Results reveal that the NBL height ranged from 180 to 300 m in the summer and from 80 to 160 m in the winter. The vertical distribution of chemical species varied by time and season, with greater concentration gradients observed in the summer. Over 90% of VOCs above the NBL were anthropogenic, while biogenic VOCs were mainly found within the NBL. Higher O3 concentration and VOC product-to-reactant ratios were observed in the residual layer, suggesting enhanced oxidation levels. This unique vertical distribution of atmospheric species at night is driven by factors, such as emission, deposition, turbulence, and atmospheric chemistry, potentially affecting ecosystem functions. Results from this study highlight the importance of incorporating NBL dynamics into atmospheric models to better understand the evolution of chemical species and their ecological effects over forests.

3.
Nano Lett ; 23(8): 3476-3483, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37040582

RESUMEN

This study demonstrates an atomic composition manipulation on Pt-Ni nano-octahedra to enhance their electrocatalytic performance. By selectively extracting Ni atoms from the {111} facets of the Pt-Ni nano-octahedra using gaseous carbon monoxide at an elevated temperature, a Pt-rich shell is formed, resulting in an ∼2 atomic layer Pt-skin. The surface-engineered octahedral nanocatalyst exhibits a significant enhancement in both mass activity (∼1.8-fold) and specific activity (∼2.2-fold) toward the oxygen reduction reaction compared with its unmodified counterpart. After 20,000 potential cycles of durability tests, the surface-etched Pt-Ni nano-octahedral sample shows a mass activity of 1.50 A/mgPt, exceeding the initial mass activity of the unetched counterpart (1.40 A/mgPt) and outperforming the benchmark Pt/C (0.18 A/mgPt) by a factor of 8. DFT calculations predict this improvement with the Pt surface layers and support these experimental observations. This surface-engineering protocol provides a promising strategy for developing novel electrocatalysts with improved catalytic features.

4.
Mol Cancer ; 19(1): 165, 2020 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-33234169

RESUMEN

Wnt signaling is a highly conserved signaling pathway that plays a critical role in controlling embryonic and organ development, as well as cancer progression. Genome-wide sequencing and gene expression profile analyses have demonstrated that Wnt signaling is involved mainly in the processes of breast cancer proliferation and metastasis. The most recent studies have indicated that Wnt signaling is also crucial in breast cancer immune microenvironment regulation, stemness maintenance, therapeutic resistance, phenotype shaping, etc. Wnt/ß-Catenin, Wnt-planar cell polarity (PCP), and Wnt-Ca2+ signaling are three well-established Wnt signaling pathways that share overlapping components and play different roles in breast cancer progression. In this review, we summarize the main findings concerning the relationship between Wnt signaling and breast cancer and provide an overview of existing mechanisms, challenges, and potential opportunities for advancing the therapy and diagnosis of breast cancer.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/patología , Microambiente Tumoral/inmunología , Vía de Señalización Wnt/efectos de los fármacos , Animales , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/metabolismo , Femenino , Humanos
5.
Ecotoxicol Environ Saf ; 194: 110456, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32171963

RESUMEN

The early stage of aggregation of cerium oxide nanoparticles (CeO2 NPs) in anion solutions was inspected in the absence and presence of extracellular polymeric substance (EPS) with a help of time-resolved dynamic light scattering (DLS). The aggregation kinetics and attachment efficiencies were calculated according to measured hydrodynamic diameter across a range of 1-500 mM NaNO3 and 0.01-100. mM Na2SO4. The aggregation of CeO2 NPs in both NaNO3 and Na2SO4 solution conformed with the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. In NaNO3 solution, the critical coagulation concentrations (CCC) of CeO2 NPs was calculated to be about 47 mM; in Na2SO4 solution, CeO2 NPs showed a re-stabilization process and thus there was no CCC value. SO42- had intenser effects on CeO2 NPs aggregation than NO3- might because of the distinction between their polarization, consisting in Hofmeister series. The presence of bound EPS (B-EPS), tightly bound EPS (TB-EPS) and loosely bound EPS (LB-EPS) in NaNO3 solutions all lead to significant decrease in CeO2 NPs aggregation. Steric repulsive force produced by absorbed EPS on CeO2 NPs might take main responsibility in stabilizing CeO2 NPs. Besides, Extended Derjaguin-Landau-Verwey-Overbeek (EDLVO) model successfully predicted the energy barrier between CeO2 NPs with B-EPS, TB-EPS and LB-EPS as a function of NaNO3 concentration. Furthermore, the difference in impeding the CeO2 NPs aggregation with B-EPS, TB-EPS and LB-EPS may be caused by the divergence in molecular weight and component mass fraction especially protein content. These results might subserve the assessment on the fate and transport behaviors of CeO2 NPs released in wastewater treatment plants.


Asunto(s)
Cerio/química , Modelos Químicos , Nanopartículas/química , Matriz Extracelular de Sustancias Poliméricas , Cinética
6.
J Am Chem Soc ; 141(3): 1235-1241, 2019 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-30561996

RESUMEN

Resolving the structure-property relationships of two-dimensional (2D) organic-inorganic hybrid perovskites is essential for the development of photovoltaic and photoelectronic devices. Here, pressure (0-10 GPa) was applied to 2D hybrid perovskite flakes mechanically exfoliated from butylammonium lead halide single crystals, (C4H9NH3)2PbI4, from which we observed a series of changes of the strong excitonic emissions in the photoluminescence spectra. By correlating with in situ high-pressure X-ray diffraction results, we examine successfully the relationship between structural modifications in the inorganic PbI42- layer and their excitonic properties. During the transition between Pbca (1b) phase and Pbca (1a) phase at around 0.1 GPa, the decrease in ⟨Pb-I-Pb⟩ bond angle and increase in Pb-I bond length lead to an abrupt blue shift of the excitonic bandgap. The presence of the P21/a phase above 1.4 GPa increases the ⟨Pb-I-Pb⟩ bond angle and decreases the Pb-I bond length, leading to a deep red shift of the excitonic bandgap. The total band gap narrowing of ∼350 meV to 2.03 eV at 5.3 GPa before amorphization, facilitates (C4H9NH3)2PbI4 as a much better solar absorber. Moreover, phase transitions inevitably modify the carrier lifetime of (C4H9NH3)2PbI4, where an initial 150 ps at ambient phase is prolongated to 190 ps in the Pbca (1a) phase along with enhanced photoluminescence (PL), originating from pressure-induced strong radiative recombination of trapped excitons.The onset of P21/a phase shortens significantly the carrier lifetime to 53 ps along with a weak PL emission due to pressure-induced severe lattice distortion and amorphization. High-pressure study on (C4H9NH3)2PbI4 nm-thin flakes may provide insights into the mechanisms for synthetically designing novel 2D hybrid perovskite based photoelectronic devices and solar cells.

7.
Cell Commun Signal ; 17(1): 109, 2019 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-31462314

RESUMEN

BACKGROUND: Breast cancer is the leading cause of cancer-related death in women worldwide. Metastatic disease remains the primary cause of death in patients with breast cancer. Basal-like breast cancer (BLBC) is associated with aggressive behavior, stem-like phenotype, high histological grade, poor clinical features, and high rates of recurrences and/or metastasis. However, the mechanism of BLBC phenotype shaping remains obscure. METHODS: Seventeen normal breast/breast cancer cell lines were used for evaluating the breast cancer subtype-markers, WNT targets and constitutive components, and epithelial mesenchymal transition (EMT) markers analysis by western blot. One hundred and twenty formalin-fixed breast cancer tissues were used for immunohistochemistry (IHC) staining. Nine online platforms (cBioPortal, CCLE, GEPIA, etc.) were used for related analyses. RESULTS: We identified Wnt5b as a key regulatory factor that governs the phenotype of BLBC by activating canonical and non-canonical WNT signaling. Wnt5b exhibited basal-like specificity in cells and clinical samples both at the mRNA and protein levels and also showed good correlation with basal-like phenotype at the mRNA level. Besides, Wnt5b was also a promising therapeutic target for LGK-974 treatment. In addition, we identified that CK1α was expressed at low levels in BLBC and that the activation of CK1α by pyrvinium was an alternative strategy for BLBC treatment. CONCLUSIONS: Wnt5b is not only a diagnostic biomarker but also a potential therapeutic target of BLBC.


Asunto(s)
Neoplasias de la Mama/metabolismo , Pirazinas/farmacología , Piridinas/farmacología , Proteínas Wnt/metabolismo , Vía de Señalización Wnt , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Humanos , Fenotipo , Proteínas Wnt/antagonistas & inhibidores , Vía de Señalización Wnt/efectos de los fármacos
8.
J Am Chem Soc ; 140(42): 13952-13957, 2018 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-30265811

RESUMEN

The pressure-induced structural evolution of formamidinium-based perovskite FAPbI3 was investigated using in situ synchrotron X-ray diffraction and laser-excited photoluminescence methods. Cubic α-FAPbI3 ( Pm3̅ m) partially and irreversibly transformed to hexagonal δ-FAPbI3 ( P63 mc) at a pressure less than 0.1 GPa. Structural transitions of α-FAPbI3 followed the sequence of Pm3̅ m → P4/ mbm → Im3̅ → partial amorphous during compression to 6.59 GPa, whereas the δ-phase converted to an orthorhombic Cmc21 structure between 1.26 and 1.73 GPa. During decompression, FAPbI3 recovered the P63 mc structure of the δ-phase as a minor component (∼18 wt %) from 2.41-1.40 GPa and the Pm3̅ m structure of the α-phase becomes dominant (∼82 wt %) at 0.10 GPa but with an increased fraction of δ-FAPbI3. The photoluminescence behaviors from both the α- and δ-forms were likely controlled by radiative recombination at the defect levels rather than band-edge emission during pressure cycling. FAPbI3 polymorphism is exquisitely sensitive to pressure. While modest pressures can engineer FAPbI3-based photovoltaic devices, irreversible δ-phase crystallization may be a limiting factor and should be taken into account.

9.
Cell Commun Signal ; 16(1): 23, 2018 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-29793495

RESUMEN

Casein kinase 1α (CK1α) is a multifunctional protein belonging to the CK1 protein family that is conserved in eukaryotes from yeast to humans. It regulates signaling pathways related to membrane trafficking, cell cycle progression, chromosome segregation, apoptosis, autophagy, cell metabolism, and differentiation in development, circadian rhythm, and the immune response as well as neurodegeneration and cancer. Given its involvement in diverse cellular, physiological, and pathological processes, CK1α is a promising therapeutic target. In this review, we summarize what is known of the biological functions of CK1α, and provide an overview of existing challenges and potential opportunities for advancing theranostics.


Asunto(s)
Caseína Quinasa Ialfa/metabolismo , Diagnóstico , Terapia Molecular Dirigida/métodos , Animales , Humanos , Neoplasias/diagnóstico , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Enfermedades Neurodegenerativas/diagnóstico , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/enzimología
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(6): 1859-63, 2016 Jun.
Artículo en Zh | MEDLINE | ID: mdl-30052406

RESUMEN

The new hybrid flocculant polyaluminum chloride-poly (dimethyl diallyl ammonium chloride) (PAC-PDMDAAC) was used to treat disperse violet and reactive brilliant red dye wastewater. The experimental results indicated that the decolorization effect of hybrid PAC-PDMDAAC was better than that of PAC and composite PAC-PDMDAAC. The decolorization rates of disperse violet and reactive brilliant red dye wastewater were 99% and 86.8% respectively when the dosages of hybrid flocculant were 400 and 450 mg·L-1. When the pH of disperse violet wastewater was 7~12, the hybrid flocculant had the best decolorization effect. When the pH of reactive brilliant red wastewater was 7~9, the hybrid flocculant had the best decolorization effect. Each of the two dyes and their flocs were characterized with FTIR. Results showed that the hybrid flocculant had a complex reaction with the dye wastewater, and the main decolorization mechanism was charge neutralization and adsorption bridging capacity. The UV scanning results indicated an adsorption peaks shift and an absorbance decreases, which further explained the main mechanism above. At the same time, it also indicated the ether linkage and ­NH2 of disperse violet were destroyed and replaced by hybrid flocculant, and the -SO3 , Cl- of reactive brilliant red were also replaced. The study will provide a new method in decolorization effiency and decolorization mechanism for the new inorganic-organic hybrid polymer flocculant. And it has significant practical meaning and application value.

11.
Angew Chem Int Ed Engl ; 55(22): 6540-4, 2016 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-27101324

RESUMEN

We report the pressure-induced crystallographic transitions and optical behavior of MAPbI3 (MA=methylammonium) using in situ synchrotron X-ray diffraction and laser-excited photoluminescence spectroscopy, supported by density functional theory (DFT) calculations using the hybrid functional B3PW91 with spin-orbit coupling. The tetragonal polymorph determined at ambient pressure transforms to a ReO3 -type cubic phase at 0.3 GPa. Upon continuous compression to 2.7 GPa this cubic polymorph converts into a putative orthorhombic structure. Beyond 4.7 GPa it separates into crystalline and amorphous fractions. During decompression, this phase-mixed material undergoes distinct restoration pathways depending on the peak pressure. In situ pressure photoluminescence investigation suggests a reduction in band gap with increasing pressure up to ≈0.3 GPa and then an increase in band gap up to a pressure of 2.7 GPa, in excellent agreement with our DFT calculation prediction.

12.
Bioorg Med Chem Lett ; 25(23): 5601-3, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26508551

RESUMEN

Herein we report a new way to identify chemical elicitors that induce resistance in rice to herbivores. Using this method, by quantifying the induction of chemicals for GUS activity in a specific screening system that we established previously, 5 candidate elicitors were selected from the 29 designed and synthesized phenoxyalkanoic acid derivatives. Bioassays confirmed that these candidate elicitors could induce plant defense and then repel feeding of white-backed planthopper Sogatella furcifera.


Asunto(s)
Resistencia a la Enfermedad , Hemípteros , Oryza , Fenoxiacetatos , Plantas Modificadas Genéticamente , Animales , Femenino , Fenoxiacetatos/química , Fenoxiacetatos/farmacología , Plantas Modificadas Genéticamente/genética
13.
J Cell Biochem ; 114(2): 346-53, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22930663

RESUMEN

LIGHT is a cytokine belonging to the TNF family. This cytokine has been extensively defined in its role on T-cell regulation and dendritic cell maturation. It also exhibits the role in liver regeneration. We recently identified its role in regulation of hematopoietic stem cell differentiation. However, the question whether this cytokine regulates mesenchymal stem cells (MSCs) proliferation and/or differentiation remains unknown. In this study, we observed that MSCs express LT-ßR but not HVEM. PCR analysis show LIGHT mRNA is undectable in MSCs. LIGHT did promote neither MSCs proliferation nor migration. However, LIGHT promoted MSCs differentiation into adipocyte which was confirmed by Oil Red O Staining Assay. Since either MSCs or adipocytes are the major cell population in bone marrow niche, we then suggest that LIGHT regulate bone marrow niche, such as MSCs differentiation.


Asunto(s)
Adipocitos/citología , Adipogénesis/genética , Células Madre Mesenquimatosas , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral , Adipocitos/metabolismo , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Diferenciación Celular , Proliferación Celular , Regulación del Desarrollo de la Expresión Génica , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones , FN-kappa B/metabolismo , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/genética , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/metabolismo
14.
World J Surg Oncol ; 11: 240, 2013 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-24060218

RESUMEN

OBJECTIVE: To evaluate the efficacy and safety of adjuvant IFN therapy for viral hepatitis-related hepatocellular carcinoma (HCC) after treatment with surgical resection or transarterial chemoembolization (TACE). METHODS: Controlled trials of adjuvant treatment with IFN for patients with HCC published between 2000 and 2012 were searched electronically in MEDLINE, PubMed, Cochrane Library, and EMBASE databases. According to the heterogeneity of the studies, two different models - the fixed-effect model and the random-effect model - were applied to analyze the results. RESULTS: Ten trials were screened according to inclusion and exclusion standards. Eight randomized, controlled trials and two non-randomized, controlled trials were included. These ten trials with a total of 1,029 subjects were eventually involved in the meta-analysis; 528 HCC patients were treated with adjuvant treatment with IFN and 501 patients with placebo. Compared to the control group, the recurrence rates of HCC in IFN group were significantly lower (odds ratio (OR) = 0.66; 95% confidence interval (CI) = 0.50 to 0.86; P = 0.02), especially after TACE treatment according to subgroup analysis (OR = 0.73; 95% CI = 0.52 to 1.01; P = 0.06 for surgical resection; and OR = 0.54; 95% CI = 0.33 to 0.86, P = 0.01 for TACE). The death rates in the IFN group also significantly decreased according to not only total events analysis (OR = 0.42; 95% CI = 0.32 to 0.56; P < 0.00001) but also subgroup analysis (OR = 0.51; 95% CI = 0.36 to 0.72; P = 0.0002 for surgical resection; and OR = 0.33; 95% CI = 0.21 to 0.50; P < 0.00001 for TACE). CONCLUSIONS: Adjuvant IFN therapy may significantly reduce the recurrence rates of patients with viral hepatitis-related HCC and improve the survival of patients after surgical resection or TACE. The ideal dose mostly selected is 3 MIU/ml, three times per week, which can make patients tolerate the adverse reactions of IFN better and maintain effective concentrations for a long time.


Asunto(s)
Antivirales/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Hepatitis Viral Humana/complicaciones , Interferón-alfa/uso terapéutico , Neoplasias Hepáticas/tratamiento farmacológico , Carcinoma Hepatocelular/etiología , Quimioterapia Adyuvante , Hepatitis Viral Humana/virología , Humanos , Neoplasias Hepáticas/etiología , Pronóstico
15.
Sci Total Environ ; 895: 165186, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37385500

RESUMEN

Groundwater contaminants from natural and anthropogenic sources pose a serious threat to the ecological environment and public health. In this study, 30 groundwater samples were collected from shallow wells at a large central water source in the North Anhui Plain, eastern China. Hydrogeochemical methods, positive matrix factorization (PMF) model, and Monte Carlo simulation were used to determine the characteristics, sources, and human health risks of inorganic and organic analytes in groundwater. The groundwater was weakly alkaline with high total hardness and was dominated by HCO3-Mg·Ca, HCO3-Ca·Mg, and HCO3-Ca·Mg·Na hydrochemical facies. The concentration of naphthalene was at a safe level, while the concentrations of F-, NO3- and Mn in 16.7 %, 26.7 % and 40 % of the samples, respectively, exceeded threshold risk-based values based on Chinese groundwater quality standards. Hydrogeochemical methods revealed that water-rock interactions (including weathering of silicate minerals, dissolution of carbonates, and cation exchange), acidity, and runoff conditions control the migration and enrichment of these analytes in groundwater. The PMF model indicated that local geogenic processes, hydrogeochemical evolution, agricultural activities, and petroleum-related industrial sources were the main factors affecting groundwater quality, with contributions of 38.2 %, 33.7 %, 17.8 %, and 10.3 %, respectively. A health risk evaluation model based on Monte Carlo simulation indicated that 77.9 % of children were exposed to a total noncarcinogenic risk above safe thresholds, about 3.4 times higher than the risk to adults. The main contributor to human health risk was F- originating from geogenic processes; thus, F- was identified as a priority for control. This study demonstrates the feasibility and reliability of combining source apportionment techniques and health risk assessment to evaluate groundwater quality.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Niño , Adulto , Humanos , Calidad del Agua , Monitoreo del Ambiente/métodos , Método de Montecarlo , Reproducibilidad de los Resultados , Contaminantes Químicos del Agua/análisis , Agua , China , Medición de Riesgo
16.
Ying Yong Sheng Tai Xue Bao ; 34(5): 1305-1312, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37236948

RESUMEN

To resolve the issue of scientific planning and rational layout of different vegetable greenhouses in Inner Mongolia Autonomous Region, we selected the days of low temperature in winter, sunshine hours, overcast days, extreme minimum temperature, days of monsoon disaster, days of snow cover in production season of greenhouse as the climate zoning indicators, based on ground-based observation data from 119 meteorological stations (1991 to 2020) and the growing demand of leafy and fruity vegetables in greenhouse, combined with the analysis of key meteorological factors in production season and the study of meteorological disaster indicators such as low temperature and cold damage, wind disaster, snow disaster. We analyzed the indices, classification and division of comprehensive climate suitability zoning of leafy and fruity vegetables at various slopes (35°, 40°) of solar greenhouse by the weighted sum method. The results showed that the climatic suitability zoning grades of leafy and fruity vegetables at 35° and 40° slope of greenhouse was highly consistent, and that the greenhouse climate suitability of leafy vegetables was higher than that of fruity vegetables in the same region. As the slope increased, wind disaster index decreased and snow disaster index increased. Climate suitability was different in areas affected by wind and snow disasters. The northeast of the study area was mainly affected by snow disasters, and the climate suitability of 40° slope was higher than 35°. The southeast of the study area was mainly affected by wind disasters, and the climate suitability of 35° slope was higher than 40°. Alxa League, Hetao Irrigation District, Tumochuan Plain, most parts of Ordos, southeast of Yanshan foothills and the south of West Liaohe Plain were the most suitable area for the solar greenhouse, because they had the suitable solar and hot resources and the low risks of wind and snow damage, which were also the key development areas of current and future facility agriculture. Due to the deficiency of solar and hot resources, high energy consumption in greenhouse production and frequent snow storms, the area around Khingan range in the northeast of Inner Mongolia was unsuitable for greenhouse.


Asunto(s)
Nieve , Verduras , Estaciones del Año , China , Agricultura , Cambio Climático
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(2): 334-8, 2012 Feb.
Artículo en Zh | MEDLINE | ID: mdl-22512163

RESUMEN

Cationic degree has been investigated as an important factor in polyacrylamide materials. Diallyl dimethyl ammonium chloride and acrylamide (PDA) was grafted by free radical polymerisation of acrylamide monomer (AM) onto the cationic monomer dimethyl diallyl ammonium chloride (DMDAAC). In the present study, near infrared reflectance spectroscopy (NIRS) was used as a rapid and accurate method to determine the cationic degree in the PDA. In this experiment, the near infrared spectra of 37 PDA samples that were self-prepared in the laboratory from 900.00 to 1 700.00 were collected. The characteristic peaks and the entire spectrum segment as the input layer neurons in radical basis function (RBF) were investigated for establishing the mathematical conversion NIRS calibration mode. For reduction of the NIR spectrum noise, the wavelet analysis was used as pretreatment process. The measured value was determined by using precipitation titration and a comparison between the simulated value and measured value was made. It was found that the external validation determination coefficient was more than 0.9, and the simulation value is in good agreement with the measured value. The statistics analysis showed that there was no significant difference between simulated value and measured value. Therefore, the calibration model (RBF neural network) established in this paper exhibited a remarkable feasibility for predicting the cationic degree of PDA based on the near infrared spectroscopy.

18.
J Hematol Oncol ; 15(1): 143, 2022 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-36209184

RESUMEN

The United States Food and Drug Administration (US FDA) has always been a forerunner in drug evaluation and supervision. Over the past 31 years, 1050 drugs (excluding vaccines, cell-based therapies, and gene therapy products) have been approved as new molecular entities (NMEs) or biologics license applications (BLAs). A total of 228 of these 1050 drugs were identified as cancer therapeutics or cancer-related drugs, and 120 of them were classified as therapeutic drugs for solid tumors according to their initial indications. These drugs have evolved from small molecules with broad-spectrum antitumor properties in the early stage to monoclonal antibodies (mAbs) and antibody‒drug conjugates (ADCs) with a more precise targeting effect during the most recent decade. These drugs have extended indications for other malignancies, constituting a cancer treatment system for monotherapy or combined therapy. However, the available targets are still mainly limited to receptor tyrosine kinases (RTKs), restricting the development of antitumor drugs. In this review, these 120 drugs are summarized and classified according to the initial indications, characteristics, or functions. Additionally, RTK-targeted therapies and immune checkpoint-based immunotherapies are also discussed. Our analysis of existing challenges and potential opportunities in drug development may advance solid tumor treatment in the future.


Asunto(s)
Antineoplásicos , Productos Biológicos , Inmunoconjugados , Neoplasias , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Productos Biológicos/uso terapéutico , Humanos , Inhibidores de Puntos de Control Inmunológico , Inmunoconjugados/uso terapéutico , Neoplasias/tratamiento farmacológico , Preparaciones Farmacéuticas , Tirosina , Estados Unidos , United States Food and Drug Administration
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(11): 2944-7, 2011 Nov.
Artículo en Zh | MEDLINE | ID: mdl-22242491

RESUMEN

In the present study, near infrared reflectance spectroscopy(NIRS) was used as a rapid and accurate method to determine the residual of acrylamide monomer in the product of diallyl dimethyl ammonium chloride and acrylamide. In this experiment 38 products were used which were self-prepared in the laboratory, then near infrared spectra of the product were scanned, seven bands were selected, the characteristic peaks of each band were used as the independent variables, and the absorption peak was used as the dependent variable, using partial least squares (PLS) method to establish the mathematical conversion near infrared reflectance spectroscopy (NIRS) calibration model. In the analysis of the spectrum, using wavelet analysis as the method of reducing the noise of spectrum, and with comparison of the simulated value and measured value, the measured value was determined by using UV spectrum, the external validation determination coefficient was found to be 0.99, and the distribution trend forecast was good. Statistics showed that there was no significant difference between simulated value and measured value. The results show that using the calibration model established by the data of near infrared spectroscopy to predict the residual AM monomer in PDA is of high feasibility.

20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(7): 1917-21, 2011 Jul.
Artículo en Zh | MEDLINE | ID: mdl-21942051

RESUMEN

In the presetn study, polymerized ferric sulphate (PFS) flocculant was prepared and tested. In the preparation of PFS flocculant, industrial by-product ferrous sulfate heptahydrate (FeSO4.7H2O) was reused as the main material. By composition with diatomite and drying up at certain temperature in vacuum drying oven, solid PFS flocculant was produced. Structural characteristics of the new flocculant product were examined through infrared spectroscopy and scanning electron microscopy (SEM), which showed that by compositing with diatomite, new group bridging emerged in the structure of PFS, which made the bond of groups stronger. In addition, part of the metalic contents in diatomite was polymerized with PFS, the product of which was polymerized ferric complex. Furthermore, the absorbing and agglomerating capacity of the diatomite carrier was significant. Considering the factors listed above, the new solid polymerized ferric sulphate (SPFS) flocculant was characterized with a larger molecule structure and enhanced absorbing, bridging and rolling sweep capacities. Through orthogonal experiment, optimum conditions of synthesis were as follows: the ratio of FeSO4.7H2O/diatomite in weight was 43/1, the reaction time is 1 h and the reaction temperature is 55 degrees C. By wastewater treatment experiment, it was found that the synthetic products showed good flocculation performance in the treatment of domestic sewage, the removal of COD was 80.00% and the removal of turbidity was 99.98%.

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