Morphologies of deltaic strandplains are the result of multiple sedimentary dynamics interacting with climate,neotectonic and anthropic impacts.They record long-term evolution of coastal areas but also reveal past and...Morphologies of deltaic strandplains are the result of multiple sedimentary dynamics interacting with climate,neotectonic and anthropic impacts.They record long-term evolution of coastal areas but also reveal past and present hazards that can be essential to better predict risks in urbanised deltas.This paper aims to identify the effect of a long-term evolution of the prograded plain of the Tiber Delta in using current ground surface variations and geohistorical data.This study applies GIS(Geographic Information System)tools to LiDAR(Light Detection and Ranging)-derived DEM(Digital Elevation Model)data combined with stratigraphical data,aerial photography interpretation and old maps.The main outcome shows areas of subsidence are primarily located in the central part of the Tiber Delta.Lower heights at the river mouth are due to subsidence and specific lower morphologies associated with fast progradation phases,while similar low heights just north in the area of the international airport of Rome are due to subsidence alone.Subsidence under the airport is associated with the compaction of the silty clay infill of the Late Pleistocene Tiber Valley mostly deposited during the Holocene transgressive period.Only observed in the airport area,the presence of washover fans and the large extent of paleolagoons reveal the kind of risks that are increased by this subsidence.This study demonstrates that the densely urbanised central part of the Tiber Delta faces higher risks of marine submersion and coastal flooding considering ongoing relative sea level change.It also contributes to show the importance to better characterise past coastal morphologies to identify areas prone to subsidence.展开更多
Growing evidence suggests that breast cancer cell plasticity arises due to a partial reactivation of epithelialmesenchymal transition(EMT) programs in order to give cells pluripotency, leading to a stemness-like pheno...Growing evidence suggests that breast cancer cell plasticity arises due to a partial reactivation of epithelialmesenchymal transition(EMT) programs in order to give cells pluripotency, leading to a stemness-like phenotype. A complete EMT would be a dead end program that would render cells unable to fully metastasize to distant organs. Evoking the EMT-mesenchymal-toepithelial transition(MET) cascade promotes successful colonization of distal target tissues. It is unlikely that direct reprogramming or trans-differentiation without passing through a pluripotent stage would be thepreferred mechanism during tumor progression. This review focuses on key EMT transcriptional regulators, EMT-transcription factors involved in EMT(TFs) and the mi RNA pathway, which are deregulated in breast cancer, and discusses their implications in cancer cell plasticity. Cross-regulation between EMT-TFs and mi RNAs, where mi RNAs act as co-repressors or co-activators, appears to be a pivotal mechanism for breast cancer cells to acquire a stem cell-like state, which is implicated both in breast metastases and tumor recurrence. As a master regulator of mi RNA biogenesis, the ribonuclease type Ⅲ endonuclease Dicer plays a central role in EMTTFs/mi RNAs regulating networks. All these EMT-MET key regulators represent valuable new prognostic and predictive markers for breast cancer as well as promising new targets for drug-resistant breast cancers.展开更多
In healthy people,balance between glucose production and its utilization is precisely controlled.When circulating glucose reaches a critical threshold level,pancreaticβcells secrete insulin that has two major actions...In healthy people,balance between glucose production and its utilization is precisely controlled.When circulating glucose reaches a critical threshold level,pancreaticβcells secrete insulin that has two major actions:to lower circulating glucose levels by facilitating its uptake mainly into skeletal muscle while inhibiting its production by the liver.Interestingly,dietary triglycerides are the main source of fatty acids to fulfill energy needs of oxidative tissues.Normally,the unconsumed fraction of excess of fatty acids is stored in lipid droplets that are localized in adipocytes to provide energy during fasting periods.Thus,adipose tissue acts as a trap for fatty acid excess liberated from plasma triglycerides.When the buffering action of adipose tissue to store fatty acids is impaired,fatty acids that build up in othertissues are metabolized as sphingolipid derivatives such as ceramides.Several studies suggest that ceramides are among the most active lipid second messengers to inhibit the insulin signaling pathway and this review describes the major role played by ceramide accumulation in the development of insulin resistance of peripherals tissues through the targeting of specific proteins of the insulin signaling pathway.展开更多
Hepatitis C virus(HCV) infects hepatocytes, polarized cells in the liver. Chronic HCV infection often leads to steatosis, fibrosis, cirrhosis and hepatocellular carcinoma, and it has been identified as the leading cau...Hepatitis C virus(HCV) infects hepatocytes, polarized cells in the liver. Chronic HCV infection often leads to steatosis, fibrosis, cirrhosis and hepatocellular carcinoma, and it has been identified as the leading cause of liver transplantation worldwide. The HCV replication cycle is dependent on lipid metabolism and particularly an accumulation of lipid droplets in host cells. Phosphoinositides(PIs) are minor phospholipids enriched in different membranes and their levels are tightly regulated by specific PI kinases and phosphatases. PIs are implicated in a vast array of cellular responses that are central to morphogenesis, such as cytoskeletal changes, cytokinesis and the recruitment of downstream effectors to govern mechanisms involved in polarization and lumen formation. Important reviews of the literature identified phosphatidylinositol(Ptd Ins) 4-kinases, and their lipid products Ptd Ins(4)P, as critical regulators of the HCV life cycle. SH2-containing inositol polyphosphate 5-phosphatase(SHIP2), phosphoinositide 3-kinase(PI3K) and their lipid products Ptd Ins(3,4)P2 and Ptd Ins(3,4,5)P3, respectively, play an important role in the cell membrane and are key to the establishment of apicobasal polarity and lumen formation. In this review, we will focus on these new functions of PI3 K and SHIP2, and their deregulation by HCV, causing a disruption of apicobasal polarity, actin organization and extracellular matrix assembly. Finally we will highlight the involvement of this pathway in the event of insulin resistance and nonalcoholic fatty liver disease related to HCV infection.展开更多
AIM:To assess the symptomatic efficacy of Lactobacillus plantarum 299v(L.plantarum 299v)(DSM 9843) for the relief of abdominal symptoms in a large subset of irritable bowel syndrome(IBS) patients fulfilling the Rome ...AIM:To assess the symptomatic efficacy of Lactobacillus plantarum 299v(L.plantarum 299v)(DSM 9843) for the relief of abdominal symptoms in a large subset of irritable bowel syndrome(IBS) patients fulfilling the Rome Ⅲ criteria.METHODS:In this double blind,placebo-controlled,parallel-designed study,subjects were randomized to daily receive either one capsule of L.plantarum 299v(DSM 9843) or placebo for 4 wk.Frequency and intensity of abdominal pain,bloating and feeling of incomplete rectal emptying were assessed weekly on a visual analogue scale while stool frequency was calculated.RESULTS:Two hundred and fourteen IBS patients were recruited.After 4 wk,both pain severity(0.68 + 0.53 vs 0.92 + 0.57,P < 0.05) and daily frequency(1.01 + 0.77 vs 1.71 + 0.93,P < 0.05) were lower with L.plantarum 299v(DSM 9843) than with placebo.Similar results were obtained for bloating.At week 4,78.1 % of the patients scored the L.plantarum 299v(DSM 9843) symptomatic effect as excellent or good vs only 8.1 % for placebo(P < 0.01).CONCLUSION:A 4-wk treatment with L.plantarum 299v(DSM 9843) provided effective symptom relief,particularly of abdominal pain and bloating,in IBS patients fulfilling the Rome Ⅲ criteria.展开更多
The bioaccumulation of PAHs and metal elements in the indigenous lichens Xanthoria parietina was monitored during two years at a quarterly frequency,in 3 sites of contrasted anthropic influence.The impact of the meteo...The bioaccumulation of PAHs and metal elements in the indigenous lichens Xanthoria parietina was monitored during two years at a quarterly frequency,in 3 sites of contrasted anthropic influence.The impact of the meteorological factors(temperature,relative humidity,rainfall,wind speed)was first estimated through principal component analysis,and then by stepwise multilinear regressions to include wind directions.The pollutants levels reflected the proximity of atmospheric emissions,in particular from a large industrial harbor.High humidity and mild temperatures,and in a lower extent low wind speed and rainfall,also favored higher concentration levels.The contributions of these meteorological aspects became minor when including wind direction,especially when approaching major emission sources.The bioaccumulation integration time towards meteorological variations was on a seasonal basis(1–2 months)but the wind direction and thus local emissions also relied on a longer time scale(12 months).This showed that the contribution of meteorological conditions may be prevalent in remote places,while secondary in polluted areas,and should be definitely taken into account regarding long-term lichen biomonitoring and inter-annual comparisons.In the same time,a quadruple sampling in each site revealed a high homogeneity among supporting tree species and topography.The resulting uncertainty,including sampling,preparation and analysis was below 30%when comfortable analytical conditions were achieved.Finally,the occurrence of unexpected events such as a major forest fire,permitted to evaluate that this type of short,although intense,events did not have a strong influence on PAH and metals bioaccumulation by lichen.展开更多
The recent discovery of cancer cell plasticity,i.e.their ability to reprogram into cancer stem cells(CSCs)either naturally or under chemotherapy and/or radiotherapy,has changed,once again,the way we consider cancer tr...The recent discovery of cancer cell plasticity,i.e.their ability to reprogram into cancer stem cells(CSCs)either naturally or under chemotherapy and/or radiotherapy,has changed,once again,the way we consider cancer treatment.If cancer stemness is a reversible epigenetic state rather than a genetic identity,opportunities will arise for therapeutic strategies that remodel epigenetic landscapes of CSCs.However,the systematic use of DNA methyltransferase and histone deacetylase inhibitors,alone or in combination,in advanced solid tumors including colorectal cancers,regardless of their molecular subtypes,does not seem to be the best strategy.In this review,we first summarize the knowledge researchers have gathered on the epigenetic signatures of CSCs with the difficulty of isolating rare populations of cells.We raise questions about the relevant use of currently available epigenetic inhibitors(epidrugs)while the expression of numerous cancer stem cell markers are often repressed by epigenetic mechanisms.These markers include the three cluster of differentiation CD133,CD44 and CD166 that have been extensively used for the isolation of colon CSCs.and.Finally,we describe current treatment strategies using epidrugs,and we hypothesize that,using correlation tools comparing associations of relevant CSC markers with chromatin modifier expression,we could identify better candidates for epienzyme targeting.展开更多
Nitrogen electro-reduction under mild conditions is one promising alternative approach of the energyconsuming Haber-Bosch process for the artificial ammonia synthesis.One critical aspect to unlocking this technology i...Nitrogen electro-reduction under mild conditions is one promising alternative approach of the energyconsuming Haber-Bosch process for the artificial ammonia synthesis.One critical aspect to unlocking this technology is to discover the catalysts with high selectivity and efficiency.In this work,the N_(2)-to-NH_(3)conversion on the functional MoS_(2)is fully investigated by density functional theory calculations since the layered MoS_(2)provides the ideal platform for the elaborating copies of the nitrogenase found in nature,wherein the functionalization is achieved via basal-adsorption,basal-substitution or edge-substitution of transition metal elements.Our results reveal that the edge-functionalization is a feasible strategy for the activity promotion;however,the basal-adsorption and basal-substitution separately suffer from the electrochemical instability and the NRR inefficiency.Specifically,MoS_(2)functionalized via edge W-substitution exhibits an exceptional activity.The energetically favored reaction pathway is through the distal pathway and a limiting potential is less than 0.20 V.Overall,this work escalates the rational design of the high-effective catalysts for nitrogen fixation and provides the explanation why the predicated catalyst have a good performance,paving the guidance for the experiments.展开更多
BACKGROUND When combined with vanadium salts,catecholamines strongly activate glucose uptake in rat and mouse adipocytes.AIM To test whether catecholamines activate glucose transport in human adipocytes.METHODS The up...BACKGROUND When combined with vanadium salts,catecholamines strongly activate glucose uptake in rat and mouse adipocytes.AIM To test whether catecholamines activate glucose transport in human adipocytes.METHODS The uptake of 2-deoxyglucose(2-DG)was measured in adipocytes isolated from pieces of abdominal subcutaneous tissue removed from women undergoing reconstructive surgery.Pharmacological approaches with amine oxidase inhibitors,adrenoreceptor agonists and antioxidants were performed to unravel the mechanisms of action of noradrenaline or adrenaline(also named epinephrine).RESULTS In human adipocytes,45-min incubation with 100μmol/L adrenaline or noradrenaline activated 2-DG uptake up to more than one-third of the maximal response to insulin.This stimulation was not reproduced with millimolar doses of dopamine or serotonin and was not enhanced by addition of vanadate to the incubation medium.Among various natural amines and adrenergic agonists tested,no other molecule was more efficient than adrenaline and noradrenaline in stimulating 2-DG uptake.The effect of the catecholamines was not impaired by pargyline and semicarbazide,contrarily to that of benzylamine or methylamine,which are recognized substrates of semicarbazide-sensitive amine oxidase.Hydrogen peroxide at 1 mmol/L activated hexose uptake but not pyrocatechol or benzoquinone,and only the former was potentiated by vanadate.Catalase and the phosphoinositide 3-kinase inhibitor wortmannin inhibited adrenaline-induced activation of 2-DG uptake.CONCLUSION High doses of catecholamines exert insulin-like actions on glucose transport in human adipocytes.At submillimolar doses,vanadium did not enhance this catecholamine activation of glucose transport.Consequently,this dismantles our previous suggestion to combine the metal ion with catecholamines to improve the benefit/risk ratio of vanadium-based antidiabetic approaches.展开更多
Few studies have analyzed the effect of ve- nous thromboembolism （VTE） events on the prognosis of pancreatic cancer, but their results were conflicting. The pres- ent study was undertaken to determine the effect of ...Few studies have analyzed the effect of ve- nous thromboembolism （VTE） events on the prognosis of pancreatic cancer, but their results were conflicting. The pres- ent study was undertaken to determine the effect of VTE on pancreatic adenocarcinoma （PA） outcomes. METHODS： All consecutive patients diagnosed with PA from May 2004 to January 2012 in a single oncology center were retrospectively studied. Clinical, radiological and histologi- cal data at time of diagnosis or within the first 3 months after surgery, including the presence （＋） or absence （-） of VTE were collected. VTE was defined as radiological evidence of either pulmonary embolism （PE）, deep venous thrombosis without infection or catheter-related thrombosis. PA with and without PE was compared for survival using the Kaplan-Meier method to estimate overall survival. RESULTS： Among 162 PA patients with a median follow-up of 15 （3-92） months after diagnosis, 28 demonstratedVTE （＋）. PA patients with and without PE were similar for age, American Society of Anesthesiologist score, body mass index, and histo- ry of treatment. The distribution of cancer stages was similarbetween the two groups VTE （＋） and VTE （-）. The median du- ration of survival was significantly worse in the VTE （＋） group vs VTE （-） （12 vs 18 months, P=0.010）. In multivariate analysis, the presence of VTE and surgical treatment were independent prognostic factors for overall survival. CONCLUSION： VTE （＋） at time of diagnosis or within the first 3 months after surgery during treatment is an indepen- dent factor of poor prognosis in PA.展开更多
Launaea taraxacifolia is a leafy vegetable of the family of Asteraceae (Compositae) found in several countries in West Africa including Ghana, Benin and Nigeria. The plant leaves are eaten either fresh as salad or coo...Launaea taraxacifolia is a leafy vegetable of the family of Asteraceae (Compositae) found in several countries in West Africa including Ghana, Benin and Nigeria. The plant leaves are eaten either fresh as salad or cooked as sauces. They are also consumed as infusion to fight against several diseases including non-communicable diseases such as diabetes and hypertension. Several studies have been conducted in Ghana, Nigeria on the nutritional and medicinal values of this plant but no study has yet been conducted in Benin on the virtues of this plant. In this work we have achieved the phytochemical characterization and evaluated the cytotoxicity as well as hypolipidemic and anti-oxidant effects of the ethanol-aqueous extracts of Launaea taraxacifolia leaves. Cytotoxicity and hypolipidemic activities have been performed on HepG2 cells;the antioxidant effect has been performed on the PLB985 cells. The results showed that the ethanol-aqueous extracts of Launaea taraxacifolia leaves contained the following metabolites: catechic tannin, flavonoids, phenolic acids, mucilage and leucoanthocyanins. Only very high concentrations (>20 mg/ml) of leaves extracts are toxic for HepG2 cells. Launaea taraxacifolia leaves have significant antioxidant and hypolipidemic activities.展开更多
In the world,among all type of cancers,colorectal cancer(CRC)is the third most commonly diagnosed in males and the second in females.In most of cases,(RP1)patients’prognosis limitation with malignant tumors can be at...In the world,among all type of cancers,colorectal cancer(CRC)is the third most commonly diagnosed in males and the second in females.In most of cases,(RP1)patients’prognosis limitation with malignant tumors can be attributed to delayed diagnosis of the disease.Identification of patients with early-stage disease leads to more effective therapeutic interventions.Therefore,new screening methods and further innovative treatment approaches are mandatory as they may lead to an increase in progression-free and overall survival rates.For the last decade,the interest in extracellular vesicles(EVs)research has exponentially increased as EVs generation appears to be a universal feature of every cell that is strongly involved in many mechanisms of cell-cell communication either in physiological or pathological situations.EVs can cargo biomolecules,such as lipids,proteins,nucleic acids and generate transmission signal through the intercellular transfer of their content.By this mechanism,tumor cells can recruit and modify the adjacent and systemic microenvironment to support further invasion and dissemination.This review intends to cover the most recent literature on the role of EVs production in colorectal normal and cancer tissues.Specific attention is paid to the use of EVs for early CRC diagnosis,follow-up,and prognosis as EVs have come into the spotlight of research as a high potential source of‘liquid biopsies’.The use of EVs as new targets or nanovectors as drug delivery systems for CRC therapy is also summarized.展开更多
The rare earth-iron-boron magnets based on high abundance rare earths(REs)show potential for costeffective permanent magnets but their hard magnetic properties have to be greatly improved.The grain boundary diffusion ...The rare earth-iron-boron magnets based on high abundance rare earths(REs)show potential for costeffective permanent magnets but their hard magnetic properties have to be greatly improved.The grain boundary diffusion process(GBDP)is known as an effective way to improve the coercivity of Nd-Fe-B magnets,however,the conventional diffusion method faces a challenge for Ce-based magnets since there is no enough continuous GB layer as the diffusion channel.Here,a two-step(Nd-Cu doping followed by Nd-Cu diffusion)GBDP was introduced for hot deformed(Ce,La,Y)-Fe-B magnet,and the excellent magnetic properties ofμ0Hc=0.63 T,μ0Mr=0.68 T,and(BH)max=72.4 kJ/m^(3)were achieved.The Nd-Cu doping helps the formation of RE-rich GB layer,and then it acts as the diffusion channel for increasing the ef-ficiency of the subsequent Nd-Cu diffusion and results in the increased volume fraction of continuously distributed GB phase,whose paramagnetism was verified by 57Fe Mössbauer spectrometry.Those paramagnetic GB phases help to form the discontinuous domain walls,as observed by Lorentz transmission electron microscopy,and break the magnetic exchange coupling of RE2Fe14B grains.It thus contributes to the coercivity enhancement of the hot deformed magnet with two-step diffusion,which is further proved by micromagnetic simulation.This study proposes a potential technique to prepare anisotropic hot deformed(Ce,La,Y)-Fe-B magnet with high cost-performance.展开更多
In many sexually reproducing species, individuals can gather information about potential mates by observing their mating success. This behavioral pattern, that we call mate-copying, was reported in the fruit fly Droso...In many sexually reproducing species, individuals can gather information about potential mates by observing their mating success. This behavioral pattern, that we call mate-copying, was reported in the fruit fly Drosophila rnelanogaster where females choosing between 2 males of contrasting phenotypes can build a preference for males of the phenotype they previously saw being chosen by a demonstrator female. As sex ratio is known to affect mate choice, our goal was to test whether mate-copying is also affected by encountered sex ratios. Thus, we created a gradient of sex ratio during demonstrations of mate-copying experiments by changing the number of females observ- ing from a central arena 6 simultaneous demonstrations unfolding in 6 peripheral compartments of a hexagonal device. We also tested whether the sex ratio experienced by females during demon- strations affected their choosiness （male courtship duration and double courtship rate） in subse- quent mate-choice tests. Experimental male：female sex ratio during demonstrations did not affect mate-copying indices, but positively affected the proportion of both males courting the female during mate-choice tests, as well as male courtship duration, the latter potentially explaining the for- mer relationship. As expected, the sex ratio affected female choosiness positively, and Drosophila females seem to have evolved a mate-copying ability independently of sex ratio, and a capacity to adapt their choosiness to male availability. This suggests that, as in many animal species, individuals, especially females, can adapt their mate choice depending on the current sex ratio.展开更多
The electrochemical nitrogen reduction reaction(NRR)for the ammonia production under ambient conditions is regarded as a sustainable alternative to the industrial Haber-Bosch process.However,the electrocatalytic syste...The electrochemical nitrogen reduction reaction(NRR)for the ammonia production under ambient conditions is regarded as a sustainable alternative to the industrial Haber-Bosch process.However,the electrocatalytic systems that efficiently catalyze nitrogen reduction remain elusive.In the work,the nitrogen reduction activity of the transition metal decorated bismuthene TM@Bis is fully investigated by means of density functional theory calculations.Our results demonstrate that W@Bis delivers the best efficiency,wherein the potential-determining step is located at the last protonation step of^(*)NH_(2)+H^(+)+e^(-)→*NH_(3)via the distal mechanism with the limiting potential ULof 0.26 V.Furthermore,the dopants of Re and Os are also promising candidates for experimental synthesis due to its good selectivity,in despite of the slightly higher ULof NRR with the value of 0.55 V.However,the candidates of Ti,V,Nb and Mo delivered the relative lower ULof 0.35,0.37,0.41 and 0.43 V might be suffered from the side hydrogen evolution reaction.More interestingly,a volcano curve is established between ULand valence electrons of metal elements wherein W with 4 electrons in d band located at the summit.Such phenomenon originates from the underlying acceptance-back donation mechanism.Therefore,our work provides a fundament understanding for the material design for nitrogen reduction electrocatalysis.展开更多
There is an increasing interest in developing nanoparticles with diverse biologic activities.To this end,we prepared 10 to 15 nm silver nanoparticles(AgNP)from native isolates of Trichoderma atroviride.Within this stu...There is an increasing interest in developing nanoparticles with diverse biologic activities.To this end,we prepared 10 to 15 nm silver nanoparticles(AgNP)from native isolates of Trichoderma atroviride.Within this study,endophytic fungi hosted four medicinal plants in Saint Katherine Protectorate,South Sinai,Egypt have been isolated by surface sterilization technique on four isolation media.Ten species,based on their frequency of occurrence,out of twenty recovered taxa were tested for their capability to synthesize extracellular AgNPs.Trichoderma atroviride hosted Chiliadenus montanus was found to be the best candidate for the production of mycogenic AgNPs among all examined species.The mycosynthesized AgNPs were compared with chemically synthesized and characterized using Ultraviolet-visible(UV-vis)spectroscopy,Raman spectroscopy,X-ray diffraction(XRD)and high-resolution transmission electron microscopy(HRTEM)techniques.The HRTEM result showed the distribution of spherical AgNPs ranging from 10 to 15 nm.Trichoderma atroviride isolate was subjected to sequencing for confirmation of phenotypic identification.The internal transcribed spacer(ITS)1-5.8 s-ITS2 rDNA sequences obtained were compared with those deposited in the GenBank Database and registered with accession number MH283876 in the NCBI Database.Antibacterial,anticandidal and antifungal effects of chemically and mycosynthesized AgNPs were examined at various concentrations in vitro against six pathogenic bacteria and 4 pathogenic fungi by agar well diffusion technique.Standard antibiotics;Gentamicin,Amoxicillin,Clotrimazole,and Nystatin at 5μg/disk were taken as positive controls,while 5%DMSO was used as the negative control.Our data revealed that the application of mycogenic AgNPs at a concentration of 100 ppm resulted in maximum inhibition of pathogenic bacteria and fungi.These data suggest that AgNPs from native isolates of Trichoderma atroviride(MH283876)offer a source of rapid synthesis of eco-friendly,economical biomaterials that show antimicrobial activities.展开更多
This review summarizes the recent advances on the application of ^(57)Fe Mössbauer spectrometry to study the magnetic and phase characteristics of Nd–Fe–B-based permanent magnets. First of all, the hyperfine st...This review summarizes the recent advances on the application of ^(57)Fe Mössbauer spectrometry to study the magnetic and phase characteristics of Nd–Fe–B-based permanent magnets. First of all, the hyperfine structures of the Ce_(2)Fe_(14)B,(Ce,Nd)_(2)Fe_(14)B and MM_(2)Fe_(14)B phases are well-defined by using the model based on the Wigner-Seitz analysis of the crystal structure. The results show that the isomer shift δ and the quadrupole splitting öEQ of those 2:14:1 phases show minor changes with the Nd content, while the hyperfine field Bhfincreases monotonically with increasing Nd content and its value is influenced by the element segregation and phase separation in the 2:14:1 phase. Then, the hyperfine structures of the low fraction secondary phases are determined by the ^(57)Fe Mössbauer spectrometry due to its high sensitivity. On this basis,the content, magnetic behavior, and magnetization of the REFe_(2) phase, the amorphous grain boundary(GB) phase, and the amorphous worm-like phase, as well as their effects on the magnetic properties, are systematically studied.展开更多
Hepatocellular carcinoma（HCC）is one of the leading causes of cancer related death in Asia and Africa（1）.It reflects the high burden of hepatitis B virus（HBV）infection in these areas.Curative treatments of HCC as...Hepatocellular carcinoma（HCC）is one of the leading causes of cancer related death in Asia and Africa（1）.It reflects the high burden of hepatitis B virus（HBV）infection in these areas.Curative treatments of HCC as radiofrequency ablation and resection are impaired by a high rate of tumor recurrence.However,most of the time,HCC is frequently diagnosed at advanced stages where only展开更多
The Beni Bousera massif(Rifean belt,northern Morocco)is predominantly composed of spinel lherzolite with subordinate garnet pyroxenite and garnet peridotite layers.It formed an antiformal dome which was overlain by gr...The Beni Bousera massif(Rifean belt,northern Morocco)is predominantly composed of spinel lherzolite with subordinate garnet pyroxenite and garnet peridotite layers.It formed an antiformal dome which was overlain by graphite-sillimanite-garnet gneisses(kinzigites)equilibrated at around 1 GPa and 750℃.Within these kinzigites,kyanite-bearing basic granulites record somewhat higher PT conditions of around 1.6-2.0 GPa and 760-820℃.Garnet clinopyroxenite(either graphite-bearing or graphi-展开更多
文摘Morphologies of deltaic strandplains are the result of multiple sedimentary dynamics interacting with climate,neotectonic and anthropic impacts.They record long-term evolution of coastal areas but also reveal past and present hazards that can be essential to better predict risks in urbanised deltas.This paper aims to identify the effect of a long-term evolution of the prograded plain of the Tiber Delta in using current ground surface variations and geohistorical data.This study applies GIS(Geographic Information System)tools to LiDAR(Light Detection and Ranging)-derived DEM(Digital Elevation Model)data combined with stratigraphical data,aerial photography interpretation and old maps.The main outcome shows areas of subsidence are primarily located in the central part of the Tiber Delta.Lower heights at the river mouth are due to subsidence and specific lower morphologies associated with fast progradation phases,while similar low heights just north in the area of the international airport of Rome are due to subsidence alone.Subsidence under the airport is associated with the compaction of the silty clay infill of the Late Pleistocene Tiber Valley mostly deposited during the Holocene transgressive period.Only observed in the airport area,the presence of washover fans and the large extent of paleolagoons reveal the kind of risks that are increased by this subsidence.This study demonstrates that the densely urbanised central part of the Tiber Delta faces higher risks of marine submersion and coastal flooding considering ongoing relative sea level change.It also contributes to show the importance to better characterise past coastal morphologies to identify areas prone to subsidence.
基金Supported by The Ligue Nationale contre le Cancer,to Puisieux A
文摘Growing evidence suggests that breast cancer cell plasticity arises due to a partial reactivation of epithelialmesenchymal transition(EMT) programs in order to give cells pluripotency, leading to a stemness-like phenotype. A complete EMT would be a dead end program that would render cells unable to fully metastasize to distant organs. Evoking the EMT-mesenchymal-toepithelial transition(MET) cascade promotes successful colonization of distal target tissues. It is unlikely that direct reprogramming or trans-differentiation without passing through a pluripotent stage would be thepreferred mechanism during tumor progression. This review focuses on key EMT transcriptional regulators, EMT-transcription factors involved in EMT(TFs) and the mi RNA pathway, which are deregulated in breast cancer, and discusses their implications in cancer cell plasticity. Cross-regulation between EMT-TFs and mi RNAs, where mi RNAs act as co-repressors or co-activators, appears to be a pivotal mechanism for breast cancer cells to acquire a stem cell-like state, which is implicated both in breast metastases and tumor recurrence. As a master regulator of mi RNA biogenesis, the ribonuclease type Ⅲ endonuclease Dicer plays a central role in EMTTFs/mi RNAs regulating networks. All these EMT-MET key regulators represent valuable new prognostic and predictive markers for breast cancer as well as promising new targets for drug-resistant breast cancers.
基金Supported by INSERM,the SociétéFrancophone du Diabètean Agence Nationale de la Recherche grant project(Crisalis)
文摘In healthy people,balance between glucose production and its utilization is precisely controlled.When circulating glucose reaches a critical threshold level,pancreaticβcells secrete insulin that has two major actions:to lower circulating glucose levels by facilitating its uptake mainly into skeletal muscle while inhibiting its production by the liver.Interestingly,dietary triglycerides are the main source of fatty acids to fulfill energy needs of oxidative tissues.Normally,the unconsumed fraction of excess of fatty acids is stored in lipid droplets that are localized in adipocytes to provide energy during fasting periods.Thus,adipose tissue acts as a trap for fatty acid excess liberated from plasma triglycerides.When the buffering action of adipose tissue to store fatty acids is impaired,fatty acids that build up in othertissues are metabolized as sphingolipid derivatives such as ceramides.Several studies suggest that ceramides are among the most active lipid second messengers to inhibit the insulin signaling pathway and this review describes the major role played by ceramide accumulation in the development of insulin resistance of peripherals tissues through the targeting of specific proteins of the insulin signaling pathway.
基金Supported by Agence Nationale de Recherche sur le Sida et les hépatites(ANRS,France),Ligue contre le cancer,France
文摘Hepatitis C virus(HCV) infects hepatocytes, polarized cells in the liver. Chronic HCV infection often leads to steatosis, fibrosis, cirrhosis and hepatocellular carcinoma, and it has been identified as the leading cause of liver transplantation worldwide. The HCV replication cycle is dependent on lipid metabolism and particularly an accumulation of lipid droplets in host cells. Phosphoinositides(PIs) are minor phospholipids enriched in different membranes and their levels are tightly regulated by specific PI kinases and phosphatases. PIs are implicated in a vast array of cellular responses that are central to morphogenesis, such as cytoskeletal changes, cytokinesis and the recruitment of downstream effectors to govern mechanisms involved in polarization and lumen formation. Important reviews of the literature identified phosphatidylinositol(Ptd Ins) 4-kinases, and their lipid products Ptd Ins(4)P, as critical regulators of the HCV life cycle. SH2-containing inositol polyphosphate 5-phosphatase(SHIP2), phosphoinositide 3-kinase(PI3K) and their lipid products Ptd Ins(3,4)P2 and Ptd Ins(3,4,5)P3, respectively, play an important role in the cell membrane and are key to the establishment of apicobasal polarity and lumen formation. In this review, we will focus on these new functions of PI3 K and SHIP2, and their deregulation by HCV, causing a disruption of apicobasal polarity, actin organization and extracellular matrix assembly. Finally we will highlight the involvement of this pathway in the event of insulin resistance and nonalcoholic fatty liver disease related to HCV infection.
基金Supported by Rosell-Lallemand Institute,France and Probi AB,Sweden
文摘AIM:To assess the symptomatic efficacy of Lactobacillus plantarum 299v(L.plantarum 299v)(DSM 9843) for the relief of abdominal symptoms in a large subset of irritable bowel syndrome(IBS) patients fulfilling the Rome Ⅲ criteria.METHODS:In this double blind,placebo-controlled,parallel-designed study,subjects were randomized to daily receive either one capsule of L.plantarum 299v(DSM 9843) or placebo for 4 wk.Frequency and intensity of abdominal pain,bloating and feeling of incomplete rectal emptying were assessed weekly on a visual analogue scale while stool frequency was calculated.RESULTS:Two hundred and fourteen IBS patients were recruited.After 4 wk,both pain severity(0.68 + 0.53 vs 0.92 + 0.57,P < 0.05) and daily frequency(1.01 + 0.77 vs 1.71 + 0.93,P < 0.05) were lower with L.plantarum 299v(DSM 9843) than with placebo.Similar results were obtained for bloating.At week 4,78.1 % of the patients scored the L.plantarum 299v(DSM 9843) symptomatic effect as excellent or good vs only 8.1 % for placebo(P < 0.01).CONCLUSION:A 4-wk treatment with L.plantarum 299v(DSM 9843) provided effective symptom relief,particularly of abdominal pain and bloating,in IBS patients fulfilling the Rome Ⅲ criteria.
基金This work was fully funded by the“InstitutÉcocitoyen pour la Connaissance des Pollutions”.
文摘The bioaccumulation of PAHs and metal elements in the indigenous lichens Xanthoria parietina was monitored during two years at a quarterly frequency,in 3 sites of contrasted anthropic influence.The impact of the meteorological factors(temperature,relative humidity,rainfall,wind speed)was first estimated through principal component analysis,and then by stepwise multilinear regressions to include wind directions.The pollutants levels reflected the proximity of atmospheric emissions,in particular from a large industrial harbor.High humidity and mild temperatures,and in a lower extent low wind speed and rainfall,also favored higher concentration levels.The contributions of these meteorological aspects became minor when including wind direction,especially when approaching major emission sources.The bioaccumulation integration time towards meteorological variations was on a seasonal basis(1–2 months)but the wind direction and thus local emissions also relied on a longer time scale(12 months).This showed that the contribution of meteorological conditions may be prevalent in remote places,while secondary in polluted areas,and should be definitely taken into account regarding long-term lichen biomonitoring and inter-annual comparisons.In the same time,a quadruple sampling in each site revealed a high homogeneity among supporting tree species and topography.The resulting uncertainty,including sampling,preparation and analysis was below 30%when comfortable analytical conditions were achieved.Finally,the occurrence of unexpected events such as a major forest fire,permitted to evaluate that this type of short,although intense,events did not have a strong influence on PAH and metals bioaccumulation by lichen.
基金Supported by"Institut National de la Sante et de la Recherche Médicale"(Inserm)"Centre National de la Recherche Scientifique"(CNRS)"la Ligue Nationale contre le Cancer"(Committees 59,60 and 62)
文摘The recent discovery of cancer cell plasticity,i.e.their ability to reprogram into cancer stem cells(CSCs)either naturally or under chemotherapy and/or radiotherapy,has changed,once again,the way we consider cancer treatment.If cancer stemness is a reversible epigenetic state rather than a genetic identity,opportunities will arise for therapeutic strategies that remodel epigenetic landscapes of CSCs.However,the systematic use of DNA methyltransferase and histone deacetylase inhibitors,alone or in combination,in advanced solid tumors including colorectal cancers,regardless of their molecular subtypes,does not seem to be the best strategy.In this review,we first summarize the knowledge researchers have gathered on the epigenetic signatures of CSCs with the difficulty of isolating rare populations of cells.We raise questions about the relevant use of currently available epigenetic inhibitors(epidrugs)while the expression of numerous cancer stem cell markers are often repressed by epigenetic mechanisms.These markers include the three cluster of differentiation CD133,CD44 and CD166 that have been extensively used for the isolation of colon CSCs.and.Finally,we describe current treatment strategies using epidrugs,and we hypothesize that,using correlation tools comparing associations of relevant CSC markers with chromatin modifier expression,we could identify better candidates for epienzyme targeting.
基金financial support from the National Natural Science Foundation of China(21503097,52130101,51701152,21806023,and 51702345)China Scholarship Council(202008320215).
文摘Nitrogen electro-reduction under mild conditions is one promising alternative approach of the energyconsuming Haber-Bosch process for the artificial ammonia synthesis.One critical aspect to unlocking this technology is to discover the catalysts with high selectivity and efficiency.In this work,the N_(2)-to-NH_(3)conversion on the functional MoS_(2)is fully investigated by density functional theory calculations since the layered MoS_(2)provides the ideal platform for the elaborating copies of the nitrogenase found in nature,wherein the functionalization is achieved via basal-adsorption,basal-substitution or edge-substitution of transition metal elements.Our results reveal that the edge-functionalization is a feasible strategy for the activity promotion;however,the basal-adsorption and basal-substitution separately suffer from the electrochemical instability and the NRR inefficiency.Specifically,MoS_(2)functionalized via edge W-substitution exhibits an exceptional activity.The energetically favored reaction pathway is through the distal pathway and a limiting potential is less than 0.20 V.Overall,this work escalates the rational design of the high-effective catalysts for nitrogen fixation and provides the explanation why the predicated catalyst have a good performance,paving the guidance for the experiments.
文摘BACKGROUND When combined with vanadium salts,catecholamines strongly activate glucose uptake in rat and mouse adipocytes.AIM To test whether catecholamines activate glucose transport in human adipocytes.METHODS The uptake of 2-deoxyglucose(2-DG)was measured in adipocytes isolated from pieces of abdominal subcutaneous tissue removed from women undergoing reconstructive surgery.Pharmacological approaches with amine oxidase inhibitors,adrenoreceptor agonists and antioxidants were performed to unravel the mechanisms of action of noradrenaline or adrenaline(also named epinephrine).RESULTS In human adipocytes,45-min incubation with 100μmol/L adrenaline or noradrenaline activated 2-DG uptake up to more than one-third of the maximal response to insulin.This stimulation was not reproduced with millimolar doses of dopamine or serotonin and was not enhanced by addition of vanadate to the incubation medium.Among various natural amines and adrenergic agonists tested,no other molecule was more efficient than adrenaline and noradrenaline in stimulating 2-DG uptake.The effect of the catecholamines was not impaired by pargyline and semicarbazide,contrarily to that of benzylamine or methylamine,which are recognized substrates of semicarbazide-sensitive amine oxidase.Hydrogen peroxide at 1 mmol/L activated hexose uptake but not pyrocatechol or benzoquinone,and only the former was potentiated by vanadate.Catalase and the phosphoinositide 3-kinase inhibitor wortmannin inhibited adrenaline-induced activation of 2-DG uptake.CONCLUSION High doses of catecholamines exert insulin-like actions on glucose transport in human adipocytes.At submillimolar doses,vanadium did not enhance this catecholamine activation of glucose transport.Consequently,this dismantles our previous suggestion to combine the metal ion with catecholamines to improve the benefit/risk ratio of vanadium-based antidiabetic approaches.
基金supported by institutional funding from INSERM(Paris,France)the Aix-Marseille University(Marseille,France)by a grant INCAa-DGSO-INSERM 6038 from sites de recherche intégrésur le cancer(SIRIC)
文摘Few studies have analyzed the effect of ve- nous thromboembolism （VTE） events on the prognosis of pancreatic cancer, but their results were conflicting. The pres- ent study was undertaken to determine the effect of VTE on pancreatic adenocarcinoma （PA） outcomes. METHODS： All consecutive patients diagnosed with PA from May 2004 to January 2012 in a single oncology center were retrospectively studied. Clinical, radiological and histologi- cal data at time of diagnosis or within the first 3 months after surgery, including the presence （＋） or absence （-） of VTE were collected. VTE was defined as radiological evidence of either pulmonary embolism （PE）, deep venous thrombosis without infection or catheter-related thrombosis. PA with and without PE was compared for survival using the Kaplan-Meier method to estimate overall survival. RESULTS： Among 162 PA patients with a median follow-up of 15 （3-92） months after diagnosis, 28 demonstratedVTE （＋）. PA patients with and without PE were similar for age, American Society of Anesthesiologist score, body mass index, and histo- ry of treatment. The distribution of cancer stages was similarbetween the two groups VTE （＋） and VTE （-）. The median du- ration of survival was significantly worse in the VTE （＋） group vs VTE （-） （12 vs 18 months, P=0.010）. In multivariate analysis, the presence of VTE and surgical treatment were independent prognostic factors for overall survival. CONCLUSION： VTE （＋） at time of diagnosis or within the first 3 months after surgery during treatment is an indepen- dent factor of poor prognosis in PA.
文摘Launaea taraxacifolia is a leafy vegetable of the family of Asteraceae (Compositae) found in several countries in West Africa including Ghana, Benin and Nigeria. The plant leaves are eaten either fresh as salad or cooked as sauces. They are also consumed as infusion to fight against several diseases including non-communicable diseases such as diabetes and hypertension. Several studies have been conducted in Ghana, Nigeria on the nutritional and medicinal values of this plant but no study has yet been conducted in Benin on the virtues of this plant. In this work we have achieved the phytochemical characterization and evaluated the cytotoxicity as well as hypolipidemic and anti-oxidant effects of the ethanol-aqueous extracts of Launaea taraxacifolia leaves. Cytotoxicity and hypolipidemic activities have been performed on HepG2 cells;the antioxidant effect has been performed on the PLB985 cells. The results showed that the ethanol-aqueous extracts of Launaea taraxacifolia leaves contained the following metabolites: catechic tannin, flavonoids, phenolic acids, mucilage and leucoanthocyanins. Only very high concentrations (>20 mg/ml) of leaves extracts are toxic for HepG2 cells. Launaea taraxacifolia leaves have significant antioxidant and hypolipidemic activities.
文摘In the world,among all type of cancers,colorectal cancer(CRC)is the third most commonly diagnosed in males and the second in females.In most of cases,(RP1)patients’prognosis limitation with malignant tumors can be attributed to delayed diagnosis of the disease.Identification of patients with early-stage disease leads to more effective therapeutic interventions.Therefore,new screening methods and further innovative treatment approaches are mandatory as they may lead to an increase in progression-free and overall survival rates.For the last decade,the interest in extracellular vesicles(EVs)research has exponentially increased as EVs generation appears to be a universal feature of every cell that is strongly involved in many mechanisms of cell-cell communication either in physiological or pathological situations.EVs can cargo biomolecules,such as lipids,proteins,nucleic acids and generate transmission signal through the intercellular transfer of their content.By this mechanism,tumor cells can recruit and modify the adjacent and systemic microenvironment to support further invasion and dissemination.This review intends to cover the most recent literature on the role of EVs production in colorectal normal and cancer tissues.Specific attention is paid to the use of EVs for early CRC diagnosis,follow-up,and prognosis as EVs have come into the spotlight of research as a high potential source of‘liquid biopsies’.The use of EVs as new targets or nanovectors as drug delivery systems for CRC therapy is also summarized.
基金the National Key Research and Development Program of China(Nos.2022YFB3505004,2022YFB3503400 and 2022YFB3503401)the National Natural Science Foundation of China(Nos.52071143,52171175,U21A2052,and U1908220)+3 种基金the Key R&D project of Zhejiang Province(Nos.2023C01077 and 2021C01023)the Guangdong Basic and Applied Basic Research Foundation(Nos.2023A1515010431 and 2022A1515011453)the GDAS Project of Science and Technology Development(Nos.2019GDASYL-0103067,2022GDASZH-2022010104,and 2022GDASZH-2022030604-04)the China Postdoctoral Science Foundation funded project(2022M720845).
文摘The rare earth-iron-boron magnets based on high abundance rare earths(REs)show potential for costeffective permanent magnets but their hard magnetic properties have to be greatly improved.The grain boundary diffusion process(GBDP)is known as an effective way to improve the coercivity of Nd-Fe-B magnets,however,the conventional diffusion method faces a challenge for Ce-based magnets since there is no enough continuous GB layer as the diffusion channel.Here,a two-step(Nd-Cu doping followed by Nd-Cu diffusion)GBDP was introduced for hot deformed(Ce,La,Y)-Fe-B magnet,and the excellent magnetic properties ofμ0Hc=0.63 T,μ0Mr=0.68 T,and(BH)max=72.4 kJ/m^(3)were achieved.The Nd-Cu doping helps the formation of RE-rich GB layer,and then it acts as the diffusion channel for increasing the ef-ficiency of the subsequent Nd-Cu diffusion and results in the increased volume fraction of continuously distributed GB phase,whose paramagnetism was verified by 57Fe Mössbauer spectrometry.Those paramagnetic GB phases help to form the discontinuous domain walls,as observed by Lorentz transmission electron microscopy,and break the magnetic exchange coupling of RE2Fe14B grains.It thus contributes to the coercivity enhancement of the hot deformed magnet with two-step diffusion,which is further proved by micromagnetic simulation.This study proposes a potential technique to prepare anisotropic hot deformed(Ce,La,Y)-Fe-B magnet with high cost-performance.
文摘In many sexually reproducing species, individuals can gather information about potential mates by observing their mating success. This behavioral pattern, that we call mate-copying, was reported in the fruit fly Drosophila rnelanogaster where females choosing between 2 males of contrasting phenotypes can build a preference for males of the phenotype they previously saw being chosen by a demonstrator female. As sex ratio is known to affect mate choice, our goal was to test whether mate-copying is also affected by encountered sex ratios. Thus, we created a gradient of sex ratio during demonstrations of mate-copying experiments by changing the number of females observ- ing from a central arena 6 simultaneous demonstrations unfolding in 6 peripheral compartments of a hexagonal device. We also tested whether the sex ratio experienced by females during demon- strations affected their choosiness （male courtship duration and double courtship rate） in subse- quent mate-choice tests. Experimental male：female sex ratio during demonstrations did not affect mate-copying indices, but positively affected the proportion of both males courting the female during mate-choice tests, as well as male courtship duration, the latter potentially explaining the for- mer relationship. As expected, the sex ratio affected female choosiness positively, and Drosophila females seem to have evolved a mate-copying ability independently of sex ratio, and a capacity to adapt their choosiness to male availability. This suggests that, as in many animal species, individuals, especially females, can adapt their mate choice depending on the current sex ratio.
基金the financial support from the National Natural Science Foundation of China(Nos.21503097,52130101,51701152,21806023 and 51702345)China Scholarship Council(No.202008320215)。
文摘The electrochemical nitrogen reduction reaction(NRR)for the ammonia production under ambient conditions is regarded as a sustainable alternative to the industrial Haber-Bosch process.However,the electrocatalytic systems that efficiently catalyze nitrogen reduction remain elusive.In the work,the nitrogen reduction activity of the transition metal decorated bismuthene TM@Bis is fully investigated by means of density functional theory calculations.Our results demonstrate that W@Bis delivers the best efficiency,wherein the potential-determining step is located at the last protonation step of^(*)NH_(2)+H^(+)+e^(-)→*NH_(3)via the distal mechanism with the limiting potential ULof 0.26 V.Furthermore,the dopants of Re and Os are also promising candidates for experimental synthesis due to its good selectivity,in despite of the slightly higher ULof NRR with the value of 0.55 V.However,the candidates of Ti,V,Nb and Mo delivered the relative lower ULof 0.35,0.37,0.41 and 0.43 V might be suffered from the side hydrogen evolution reaction.More interestingly,a volcano curve is established between ULand valence electrons of metal elements wherein W with 4 electrons in d band located at the summit.Such phenomenon originates from the underlying acceptance-back donation mechanism.Therefore,our work provides a fundament understanding for the material design for nitrogen reduction electrocatalysis.
文摘There is an increasing interest in developing nanoparticles with diverse biologic activities.To this end,we prepared 10 to 15 nm silver nanoparticles(AgNP)from native isolates of Trichoderma atroviride.Within this study,endophytic fungi hosted four medicinal plants in Saint Katherine Protectorate,South Sinai,Egypt have been isolated by surface sterilization technique on four isolation media.Ten species,based on their frequency of occurrence,out of twenty recovered taxa were tested for their capability to synthesize extracellular AgNPs.Trichoderma atroviride hosted Chiliadenus montanus was found to be the best candidate for the production of mycogenic AgNPs among all examined species.The mycosynthesized AgNPs were compared with chemically synthesized and characterized using Ultraviolet-visible(UV-vis)spectroscopy,Raman spectroscopy,X-ray diffraction(XRD)and high-resolution transmission electron microscopy(HRTEM)techniques.The HRTEM result showed the distribution of spherical AgNPs ranging from 10 to 15 nm.Trichoderma atroviride isolate was subjected to sequencing for confirmation of phenotypic identification.The internal transcribed spacer(ITS)1-5.8 s-ITS2 rDNA sequences obtained were compared with those deposited in the GenBank Database and registered with accession number MH283876 in the NCBI Database.Antibacterial,anticandidal and antifungal effects of chemically and mycosynthesized AgNPs were examined at various concentrations in vitro against six pathogenic bacteria and 4 pathogenic fungi by agar well diffusion technique.Standard antibiotics;Gentamicin,Amoxicillin,Clotrimazole,and Nystatin at 5μg/disk were taken as positive controls,while 5%DMSO was used as the negative control.Our data revealed that the application of mycogenic AgNPs at a concentration of 100 ppm resulted in maximum inhibition of pathogenic bacteria and fungi.These data suggest that AgNPs from native isolates of Trichoderma atroviride(MH283876)offer a source of rapid synthesis of eco-friendly,economical biomaterials that show antimicrobial activities.
基金Project supported by the Zhejiang Provincial Natural Science Foundation of China(Grant Nos.LY20E010002,LR18E010001,and LD19E010001)the National Natural Science Foundation of China(Grant Nos.U1704253 and 51801047)+2 种基金Liaoning Revitalization Talents Program(Grant No.XLYC1807177)the Key Research and Development plan of Zhejiang Province,China(Grant No.2020C05014)Ten Thousand Talents Plan of Zhejiang Province,China(Grant No.2018R52003)。
文摘This review summarizes the recent advances on the application of ^(57)Fe Mössbauer spectrometry to study the magnetic and phase characteristics of Nd–Fe–B-based permanent magnets. First of all, the hyperfine structures of the Ce_(2)Fe_(14)B,(Ce,Nd)_(2)Fe_(14)B and MM_(2)Fe_(14)B phases are well-defined by using the model based on the Wigner-Seitz analysis of the crystal structure. The results show that the isomer shift δ and the quadrupole splitting öEQ of those 2:14:1 phases show minor changes with the Nd content, while the hyperfine field Bhfincreases monotonically with increasing Nd content and its value is influenced by the element segregation and phase separation in the 2:14:1 phase. Then, the hyperfine structures of the low fraction secondary phases are determined by the ^(57)Fe Mössbauer spectrometry due to its high sensitivity. On this basis,the content, magnetic behavior, and magnetization of the REFe_(2) phase, the amorphous grain boundary(GB) phase, and the amorphous worm-like phase, as well as their effects on the magnetic properties, are systematically studied.
基金supported by HECAM (BPI), EBCI, INCa (Wnt HCC project). J-C.N.supported by a fellowship from INCa
文摘Hepatocellular carcinoma（HCC）is one of the leading causes of cancer related death in Asia and Africa（1）.It reflects the high burden of hepatitis B virus（HBV）infection in these areas.Curative treatments of HCC as radiofrequency ablation and resection are impaired by a high rate of tumor recurrence.However,most of the time,HCC is frequently diagnosed at advanced stages where only
文摘The Beni Bousera massif(Rifean belt,northern Morocco)is predominantly composed of spinel lherzolite with subordinate garnet pyroxenite and garnet peridotite layers.It formed an antiformal dome which was overlain by graphite-sillimanite-garnet gneisses(kinzigites)equilibrated at around 1 GPa and 750℃.Within these kinzigites,kyanite-bearing basic granulites record somewhat higher PT conditions of around 1.6-2.0 GPa and 760-820℃.Garnet clinopyroxenite(either graphite-bearing or graphi-
