Silver nanoparticles of diameters 3.4 to 13.2 nm grown at the interfaces between silicate glass and some oxide crystallites exhibited about six orders of magnitude reduction in resistivity for a relative humidity chan...Silver nanoparticles of diameters 3.4 to 13.2 nm grown at the interfaces between silicate glass and some oxide crystallites exhibited about six orders of magnitude reduction in resistivity for a relative humidity change from 25% to 80%. Sn-SnO2 nano core-shell structure prepared within a gel-derived silica glass film by electrodeposition technique followed by heat treatment showed large change in resistivity as a function of humidity. The resistivity also changed due to gas flow of CO2, C2H5OH and NO2, respectively. The latter arose because of reduction/oxidation of Sn4+/Sn2+ species present at the shell layer of the nanostructures. Nickel nanosheets of thickness ~0.6 nm grown within the interlayer spaces of Na-4 mica crystallites showed a change of dielectric permittivity (5%) for an applied magnetic field of 1.2 Tesla. An inhomogeneous model was used to explain this behavior. Two dimensional CuO phase was grown within the channels of diameter ~5 nm of mesoporous SiO2 structure. A magnetodielectric (MD) parameter M.D. of 4.4% was obtained in this case. BaTiO3 nanoparticles of diameter ~25 nm having pores with diameter 10 nm showed multiferroic behavior which arose due to the presence of oxygen vacancies as a result of large surface area present. An M.D. parameter of 11% was found. Similarly mesoporous LiNbO3 of 10 nm diameter showed an M.D. parameter of ~4.5% at a magnetic field 1 Tesla. A giant magnetocapacitance effect with a value of 44% at 1.5 T was observed in nickel zinc ferrite (NZF) impregnated mesoporous silica. A magnetocapacitance of 51% at magnetic field 1.7 T was found in the case of nanocomposites comprising of iron ion containing silica based nanoglass and mesoporous silica. In the last two examples the behavior was explained on the basis of Catalan model of space-charge polarization with extracted values of magnetoresistance of the NZF and nanoglass phases being 58%.展开更多
In systems in atomic and nano scales such as clusters or agglomerates constituted of particles from a few to less than one hundred of atoms, quantum confinement effects are very important. Their optical and electronic...In systems in atomic and nano scales such as clusters or agglomerates constituted of particles from a few to less than one hundred of atoms, quantum confinement effects are very important. Their optical and electronic properties are often dependent on the size of the systems and the way in which the atoms in these clusters are bonded. Generally, these nano-structures display optical and electronic properties significantly different of those found in corresponding bulk materials. Silicon agglomerates found in Silicon Rich Oxide (SRO) films have optical properties, which have reported as depended directly on nano-crystal size. Furthermore, the room temperature photoluminescence (PL) of Silicon Rich Oxides (SRO) has repeatedly generated a huge interest due to their possible applications in optoelectronic devices. However, a plausible emission mechanism has not yet widespread acceptance of the scientific community. In this research, we employed the Density Functional Theory with a functional B3LYP and a basis set 6 - 31G* to calculate the optical and electronic properties of small (six to ten silicon atoms) and medium size clusters of silicon (constituted of eleven to fourteen silicon atoms). With the theoretical calculation of the structural and optical properties of silicon clusters, it is possible to evaluate the contribution of silicon agglomerates in the luminescent emission mechanism experimentally found in thin SRO films.展开更多
End stage liver disease (ESLD) is a health problem worldwide. Liver transplantation is currently the only effective therapy, but its many drawbacks include a shortage of donors, operative damage, risk of rejection and...End stage liver disease (ESLD) is a health problem worldwide. Liver transplantation is currently the only effective therapy, but its many drawbacks include a shortage of donors, operative damage, risk of rejection and in some cases recidivism of the pre-transplant disease. These factors account for the recent growing interest in regenerative medicine. Experiments have sought to identify an optimal source of stem cells, sufficient to generate large amounts of hepatocytes to be used in bioartificial livers or injected in vivo to repair the diseased organ. This update aims to give non-stem cell specialists an overview of the results obtained to date in this fascinating field of biomedical research.展开更多
Capsule endoscopy has revoluzionized the study of the small bowel by providing a reliable method to evaluate, endoscopically, the entire small bowel. In the last six years several papers have been published exploring ...Capsule endoscopy has revoluzionized the study of the small bowel by providing a reliable method to evaluate, endoscopically, the entire small bowel. In the last six years several papers have been published exploring the possible role of this examination in different clinical conditions. At the present time capsule endoscopy is generally recommended as a third examination, after negative bidirectional endoscopy, in patients with obscure gastrointestinal bleeding. A growing body of evidence suggests also an important role for this examination in other clinical conditions such as Crohn＇s disease, celiac disease, small bowel polyposis syndromes or small bowel tumors. The main complication of this examination is the retention of the device at the site of a previously unknown small bowel stricture. However there are also some other open issues mainly due to technical limitations of this tool （which is not driven from remote control, is unable to take biopsies, to insufflate air, to suck fluids or debris and sometimes to correctly size and locate lesions）.The recently developed double balloon enteroscope, owing to its capability to explore a large part of the small bowel and to take targeted biopsies, although being invasive and time consuming, can overcome some limitations of capsule endoscopy. At the present time, in the majority of clinical conditions （i.e. obscure GI bleeding）, the winning strategy seems to be to couple these two techniques to explore the small bowel in a painless, safe and complete way （with capsule endoscopy） and to define and treat the lesions identified （with double balloon enteroscopy）.展开更多
Aeromagnetic interference could not be compensated effectively if the precision of parameters which are solved by the aircraft magnetic field model is low. In order to improve the compensation effect under this condit...Aeromagnetic interference could not be compensated effectively if the precision of parameters which are solved by the aircraft magnetic field model is low. In order to improve the compensation effect under this condition, a method based on small signal model and least mean square（LMS） algorithm is proposed. According to the method, the initial values of adaptive filter＇s weight vector are calculated with the solved model parameters through small signal model at first,then the small amount of direction cosine and its derivative are set as the input of the filter, and the small amount of the interference is set as the filter＇s expected vector. After that, the aircraft magnetic interference is compensated by LMS algorithm. Finally, the method is verified by simulation and experiment. The result shows that the compensation effect can be improved obviously by the LMS algorithm when original solved parameters have low precision. The method can further improve the compensation effect even if the solved parameters have high precision.展开更多
Aqueous extracts from various plant parts of fenugreek(3%)(aerial parts:leaves and stems(LS),roots(R),ground seeds(GS)and not ground seeds(NGS))and petroleum ether,ethyl acetate and methanolic fractions of the aerial ...Aqueous extracts from various plant parts of fenugreek(3%)(aerial parts:leaves and stems(LS),roots(R),ground seeds(GS)and not ground seeds(NGS))and petroleum ether,ethyl acetate and methanolic fractions of the aerial parts were assayed to determine their antifungal potential against Botrytis cinerea,Fusarium graminearum,Alternaria sp.,Pythium aphanidermatum,and Rhizoctinia solani.All fenugreek plant parts showed antifungal potential and the magnitude of their inhibitory effects was species and plant parts d...展开更多
This orticle seeks to address come lingering debates within sustainability studies by revealing the connections between renewable energy consumption and sustainability.Using data from 30 OECD counties,examines the con...This orticle seeks to address come lingering debates within sustainability studies by revealing the connections between renewable energy consumption and sustainability.Using data from 30 OECD counties,examines the connections via regression and geospattal analysis.Findings from the quantitative analysis indicate that about 50% of the variation in Sustainability is accounted for by the degree of renewables Consumption. The geospatial analysis visuaUv illustrates the intimate connections between the two variables, Theoretically, renewable energy relates to sustainability in three dimensions. The first dimension is economic. Relying on traditional fassil fuels eventually will bring our economy to a stop. Renewable energies, however; are able to secure our energy supply into an indefinite future. The second dimension links to ethics. To leave an intact planet torture generations is a moral responsibity of our generation, The current energy supply system is built on depletion of natural resources, while the sources of renewable energy are vast and constantly replenished. Tire last dimension is ecologic. How to allocate a proper apportionment of the global biosphere between humankind and the other life on the earth is a critical issue related to sustainability. By using renewable energy, we can greatly reduce our impact on biodiversity and therefore strike a balance between humankind and other life. Overall the research suggests that developing renewables can and in many. cases does sustain a nation＇s economic growth while simultaneously protecting the environment. It is a win-win situation. This finding undoubtedly points out a practical and realistic path for sustainable development.展开更多
The coronavirus disease 2019(COVID-19)pandemic has caused detrimental effects on many aspects of healthcare practice.Screening programs for the commonest malignancies,namely colorectal cancer(CRC),breast cancer and ce...The coronavirus disease 2019(COVID-19)pandemic has caused detrimental effects on many aspects of healthcare practice.Screening programs for the commonest malignancies,namely colorectal cancer(CRC),breast cancer and cervical cancer have been discontinued or interrupted since the beginning of restriction measures aimed to limit transmission of the new coronavirus infection.Robust evidence exists in favour of the role of screening campaigns in reducing mortality from CRC.In fact,the majority of pre-malignant lesions of the colon and rectum can be diagnosed with colonoscopy and treated by endoscopic or surgical resection.Besides,colonoscopy screening allows the diagnosis of CRCs in their pre-clinical stage.Italy was one of the first European countries where a high level of COVID-19 infections and deaths was observed,and one of the first where lockdowns and strict measures were adopted to reduce the risk of COVID-19 diffusion among the population.A systematic review of the literature was performed,including the PubMed,Scopus,Web of Sciences,and Reference Citation Analysis databases,with the aim of critically evaluating the impact of the COVID-19 pandemic on CRC screening in Italy.We found that reduction of CRC screening activity surpassed 50%in most endoscopic units,with almost 600000 fewer CRC screening exams conducted in the first 5 mo of 2020 vs the same period of 2019.While the consequences of the discontinuation of endoscopy screening for the prognosis and mortality of CRC will be evident in the next few years,recent data confirm that CRC is currently treated at a more advanced stage than in the pre-COVID-19 era.Since delays in CRC prevention and early diagnosis may translate to increased CRC-specific mortality,world healthcare systems should adopt strategies to maintain the regularity of CRC screening during subsequent peaks of the COVID-19 pandemic,or future events that might hamper screening programs.展开更多
The organization of coordinated attack and the selection of aiming point which affect hit probability were analyzed for the countermeasures taken by the hostile submarines at two helicopters' coordinated attack.A ...The organization of coordinated attack and the selection of aiming point which affect hit probability were analyzed for the countermeasures taken by the hostile submarines at two helicopters' coordinated attack.A computational model of coordinated attack parameters,a model of submarine maneuver,and a model of noise jammer were established.Compared to single helicopter' torpedo attack,the coordinated attack of two helicopters can effectively increase the hit probability of torpedo and achieve the higher target detecting probability under counterwork condition.展开更多
Background.Although cerebral auto somal dominant arte-riopathy with subcortical infarcts and leukoencephalopathy(CADASIL)is considered a cerebrovascular dis order with almost exclusively neurological sy mptoms,the art...Background.Although cerebral auto somal dominant arte-riopathy with subcortical infarcts and leukoencephalopathy(CADASIL)is considered a cerebrovascular dis order with almost exclusively neurological sy mptoms,the arteriopathy is generalized and involves choroid al and retinal vascula-ture as demonstrated by fluorescein angiographic and oc-ular electrophysiological abnorma lities.The occurrence of acute visual loss due to nonarteritic anterior ischemic optic neuropathy(NAION)has not previously been reported in CADASIL.Objective:To describe acu te visual loss due to NAION as a possible manifestation of CADASIL.Patients and Methods:The patient was a 60-year-old man with subcortical diffuse leukoencephalopathy,multi-infarct de-mentia,tetraparesis,visual loss,and a family history of stroke.We performed clinical and neuroophthalmological evaluation,electrophysiological assessment,brain mag-netic resonance imaging,and geneti c screening for muta-tions or small deletions of the Notch3gene,(causing CADASIL).Results:The patient ’s first symptom was a-cute visual loss in the right eye due t o NAION at age 27years,in absence of the common cardi ovascular risk fac-tors and before any neurological imp airment.The patient was reevaluated at age 60years,and n eu-ro-ophthalmological examination s howed optic disc atrophy in the right eye with arteriolar narrowing and a reduction in visual acuity in the left eye.Fluorescein angiography ofthe right eye showed evidence of pers istent peripapillary hypofluorescence with a retinal pig ment epithelial windows defect in the inferior temporal area.Pattern reversal visual evoked potentials were abolished in the right eye.The P100latency of the left eye was delay ed and reduced in amplitude.The diagnosis of CADASIL was confirmed by molecular analysis(heterozygotes for the C406T mutatio n on exon 3of the Notch3gene).There was a family history of cerebrovascular disorders and ocular impairment.Con-clusions:Visual loss due to transie nt or stable ischemic events involving the optic nerve hea d should be considered in the CADASIL phenotype.The possib ility of CADASIL should also be evaluated in patients with NAION who do not have cardiovascular risk factors but do have a family history of stroke.展开更多
Use of iodinated skin disinfectants in the perinatal period can result in significant iodine overload of the neonate and transient hypothyroidism.The authors report a case of unusually severe hypothyroidism requiring ...Use of iodinated skin disinfectants in the perinatal period can result in significant iodine overload of the neonate and transient hypothyroidism.The authors report a case of unusually severe hypothyroidism requiring l-thyroxine (L-T4) replacement therapy in a premature neonate after prolonged use of iodinated skin disinfectants for a complex skin lesion.Neonatal iodine overload should be minimized, and in cases with significant iodine exposure, thyroid-stimulating hormone should be monitored, especially in preterm neonates who are exquisitely sensitive to the antithyroid effects of iodine excess.展开更多
Persistent identifiers for research objects, researchers, organizations, and funders are the key to creating unambiguous and persistent connections across the global research infrastructure(GRI). Many repositories are...Persistent identifiers for research objects, researchers, organizations, and funders are the key to creating unambiguous and persistent connections across the global research infrastructure(GRI). Many repositories are implementing mechanisms to collect and integrate these identifiers into their submission and record curation processes. This bodes well for a well-connected future, but metadata for existing resources submitted in the past are missing these identifiers, thus missing the connections required for inclusion in the connected infrastructure. Re-curation of these metadata is required to make these connections. This paper introduces the global research infrastructure and demonstrates how repositories, and their user communities, can contribute to and benefit from connections to the global research infrastructure. The Dryad Data Repository has existed since 2008 and has successfully re-curated the repository metadata several times, adding identifiers for research organizations, funders, and researchers. Understanding and quantifying these successes depends on measuring repository and identifier connectivity. Metrics are described and applied to the entire repository here. Identifiers(Digital Object Identifiers, DOIs) for papers connected to datasets in Dryad have long been a critical part of the Dryad metadata creation and curation processes. Since 2019, the portion of datasets with connected papers has decreased from 100% to less than 40%. This decrease has significant ramifications for the re-curation efforts described above as connected papers have been an important source of metadata. In addition, missing connections to papers make understanding and re-using datasets more difficult. Connections between datasets and papers can be difficult to make because of time lags between submission and publication, lack of clear mechanisms for citing datasets and other research objects from papers, changing focus of researchers, and other obstacles. The Dryad community of members, i.e. users, research institutions, publishers, and funders have vested interests in identifying these connections and critical roles in the curation and re-curation efforts. Their engagement will be critical in building on the successes Dryad has already achieved and ensuring sustainable connectivity in the future.展开更多
Oleosin, caleosin and steroleosin are normally expressed in developing seed cells and are targeted to oil bodies. In the present work, the cDNA of each gene tagged with fluorescent proteins was transiently expressed i...Oleosin, caleosin and steroleosin are normally expressed in developing seed cells and are targeted to oil bodies. In the present work, the cDNA of each gene tagged with fluorescent proteins was transiently expressed into tobacco protoplasts and the fluorescent patterns observed by confocal laser scanning microscopy. Our results indicated clear differences in the endocellular localization of the three proteins. Oleosin and caleosin both share a common structure consisting of a central hydrophobic domain flanked by two hydrophilic domains and were correctly targeted to lipid droplets （LD）, whereas steroleosin, characterized by an N-terminal oil body anchoring domain, was mainly retained in the endoplasmic reticulum （ER）. Protoplast fractionation on sucrose gradients indicated that both oleosin and caleosin- green fluorescent protein （GFP） peaked at different fractions than where steroleosin-GFP or the ER marker binding immunoglobulin protein （BiP）, were recovered. Chemical analysis confirmed the presence of triacylglycerols in one of the fractions where oleosin-GFP was recovered. Finally, only oleosin- and caleosin-GFP were able to reconstitute artificial oil bodies in the presence of triacylglycerols and phospholipids. Taken together, our results pointed out for the first time that leaf LDs can be separated by the ER and both oleosin or caleosin are selectively targeted due to the existence of selective mechanisms controlling protein association with these organelles.展开更多
Piezoelectricity offers an electromechanical coupling that is widely utilized in transducer applications.There has been a consistent demand for transparent piezoelectric materials for optoelectrical applications.There...Piezoelectricity offers an electromechanical coupling that is widely utilized in transducer applications.There has been a consistent demand for transparent piezoelectric materials for optoelectrical applications.Therefore,despite the inherent tradeoff between the transparency and the piezoelectricity,numerous strategies have been explored to develop the transparent piezoelectric materials.Nonetheless,the most transparent piezoelectric materials developed to date is either a single crystal or materials that achieve transparency via hot-press sintering,limiting its industrial applicability.Therefore,we introduce a novel piezoelectric material that ensures transparency through co-doping and pressureless sintering of polycrystalline ceramics.In this study,we employed a compositional optimization approach to enhance the synergistic effect between the transparency and the piezoelectric properties of 0.71Pb(Mg_(1/3)Nb_(2/3))O_(3)–0.29PbTiO_(3)(PMN–0.29PT)ceramics.By utilizing the tape casting process for mass production and large-area manufacturing,our Pb_(0.913)La_(0.0145)Sm_(0.0145)(Mg_(1/3)Nb_(2/3))_(0.71)Ti_(0.29)O_(3)(TP2.9)ceramics exhibited over 60%transparency and large piezoelectric coefficient(d33)of 1104 pC/N.This material holds considerable promise for a wide range of industrial applications in both the optical and electronic domains.展开更多
On October 26-28,2005,in Pittsburgh,PA,key members of the building industry,green design community,healthcare industry,academic institutions,and government agencies gathered in a targeted dialogue to consider the feas...On October 26-28,2005,in Pittsburgh,PA,key members of the building industry,green design community,healthcare industry,academic institutions,and government agencies gathered in a targeted dialogue to consider the feasibility of forming a consortium to improve how healthcare facilities are planned,designed,constructed,and maintained.The roundtable formally documented the drivers and expectations of participants;instinctual,emotional,and intellectual reactions of participants to healthcare facilities greening;and the strengths,opportunities,and challenges posed by the task of greening healthcare facilities.Three areas of consensus emerged clearly from the discussion:(a)All participants supported the formation of a consortium focused on the greening of healthcare facilities;(b)All believed the mix of expertise will make this consortium unique;and(c)All believed that the development of a shared research agenda among the building industry,healthcare providers,and academia is vital.The proposed greening healthcare consortium envisions:(1)Providing a network for sharing existing research and findings related to greening of healthcare facilities;(2)Facilitating collaboration between healthcare projects,current research,and hospital performance data;and(3)Providing an informed basis for healthcare design and construction decision-making.Based on input from the roundtable discussions,eight research thrusts were identified that the proposed consortium would be ideally positioned to address based on the competencies and positions of the members.These eight research thrusts are:(1)establishing the relationships between facilities and clinical outcome;(2)defining costvalue relationships regarding green building;(3)understanding the basis for decision making;(4)compiling a data repository;(5)developing active and passive research methods;(6)investigating interdependencies;(7)minimizing or eliminating waste;and(8)implementing research.The active inter-industry discourse promoted by this consortium between the healthcare industry,building industry,and academic institutions allows for a unique dynamic to be harnessed between the“physiology”of healthcare and the“physics”of healthcare facilities.This will enable the delivery of healthcare projects and the quality of healthcare to be continuously improved and enhanced.The operational framework for the proposed consortium would rely on projects from the building and healthcare industries serving as case studies for gathering information and incorporating the developments of research at academic institutions.展开更多
Sustainable building projects have levels of complexity over conventional building projects that challenge current projectmanagement tools at efficiently managing the rigors of sustainable projects.The Continuous Valu...Sustainable building projects have levels of complexity over conventional building projects that challenge current projectmanagement tools at efficiently managing the rigors of sustainable projects.The Continuous Value EnhancementProcess(CVEP)is a recently developed tool designed specifically for sustainable building projects.This project managementtool enables project teams to systematically generate and evaluate project alternatives for meeting sustainable goals.The goal of this tool is to identify high performance solutions that increase levels of sustainability and improve projectperformance.CVEP was experimentally implemented and tested on four case study projects to evaluate its ability tosupport project management decision making in ways that elevate sustainability and project performance.Reported inthis paper,the results show CVEP produced first cost and life cycle cost savings.In particular,the study confirms thatCVEP has the capability to:1.)Provide a systematic evaluation process,2.)Collect high performance building solutions,and 3.)Be applicable to different project types.These results show that it is possible to employ targeted projectmanagement techniques,like CVEP,to improve the cost-effective provision of sustainable buildings.展开更多
文摘Silver nanoparticles of diameters 3.4 to 13.2 nm grown at the interfaces between silicate glass and some oxide crystallites exhibited about six orders of magnitude reduction in resistivity for a relative humidity change from 25% to 80%. Sn-SnO2 nano core-shell structure prepared within a gel-derived silica glass film by electrodeposition technique followed by heat treatment showed large change in resistivity as a function of humidity. The resistivity also changed due to gas flow of CO2, C2H5OH and NO2, respectively. The latter arose because of reduction/oxidation of Sn4+/Sn2+ species present at the shell layer of the nanostructures. Nickel nanosheets of thickness ~0.6 nm grown within the interlayer spaces of Na-4 mica crystallites showed a change of dielectric permittivity (5%) for an applied magnetic field of 1.2 Tesla. An inhomogeneous model was used to explain this behavior. Two dimensional CuO phase was grown within the channels of diameter ~5 nm of mesoporous SiO2 structure. A magnetodielectric (MD) parameter M.D. of 4.4% was obtained in this case. BaTiO3 nanoparticles of diameter ~25 nm having pores with diameter 10 nm showed multiferroic behavior which arose due to the presence of oxygen vacancies as a result of large surface area present. An M.D. parameter of 11% was found. Similarly mesoporous LiNbO3 of 10 nm diameter showed an M.D. parameter of ~4.5% at a magnetic field 1 Tesla. A giant magnetocapacitance effect with a value of 44% at 1.5 T was observed in nickel zinc ferrite (NZF) impregnated mesoporous silica. A magnetocapacitance of 51% at magnetic field 1.7 T was found in the case of nanocomposites comprising of iron ion containing silica based nanoglass and mesoporous silica. In the last two examples the behavior was explained on the basis of Catalan model of space-charge polarization with extracted values of magnetoresistance of the NZF and nanoglass phases being 58%.
文摘In systems in atomic and nano scales such as clusters or agglomerates constituted of particles from a few to less than one hundred of atoms, quantum confinement effects are very important. Their optical and electronic properties are often dependent on the size of the systems and the way in which the atoms in these clusters are bonded. Generally, these nano-structures display optical and electronic properties significantly different of those found in corresponding bulk materials. Silicon agglomerates found in Silicon Rich Oxide (SRO) films have optical properties, which have reported as depended directly on nano-crystal size. Furthermore, the room temperature photoluminescence (PL) of Silicon Rich Oxides (SRO) has repeatedly generated a huge interest due to their possible applications in optoelectronic devices. However, a plausible emission mechanism has not yet widespread acceptance of the scientific community. In this research, we employed the Density Functional Theory with a functional B3LYP and a basis set 6 - 31G* to calculate the optical and electronic properties of small (six to ten silicon atoms) and medium size clusters of silicon (constituted of eleven to fourteen silicon atoms). With the theoretical calculation of the structural and optical properties of silicon clusters, it is possible to evaluate the contribution of silicon agglomerates in the luminescent emission mechanism experimentally found in thin SRO films.
基金The European Association for the Study of the Liver(EASL) Sheila Sherlock Post-Doc Fellowship and by"Ordine dei Medici Chirurghi ed Odontoiatri di Bologna"(SL)
文摘End stage liver disease (ESLD) is a health problem worldwide. Liver transplantation is currently the only effective therapy, but its many drawbacks include a shortage of donors, operative damage, risk of rejection and in some cases recidivism of the pre-transplant disease. These factors account for the recent growing interest in regenerative medicine. Experiments have sought to identify an optimal source of stem cells, sufficient to generate large amounts of hepatocytes to be used in bioartificial livers or injected in vivo to repair the diseased organ. This update aims to give non-stem cell specialists an overview of the results obtained to date in this fascinating field of biomedical research.
文摘Capsule endoscopy has revoluzionized the study of the small bowel by providing a reliable method to evaluate, endoscopically, the entire small bowel. In the last six years several papers have been published exploring the possible role of this examination in different clinical conditions. At the present time capsule endoscopy is generally recommended as a third examination, after negative bidirectional endoscopy, in patients with obscure gastrointestinal bleeding. A growing body of evidence suggests also an important role for this examination in other clinical conditions such as Crohn＇s disease, celiac disease, small bowel polyposis syndromes or small bowel tumors. The main complication of this examination is the retention of the device at the site of a previously unknown small bowel stricture. However there are also some other open issues mainly due to technical limitations of this tool （which is not driven from remote control, is unable to take biopsies, to insufflate air, to suck fluids or debris and sometimes to correctly size and locate lesions）.The recently developed double balloon enteroscope, owing to its capability to explore a large part of the small bowel and to take targeted biopsies, although being invasive and time consuming, can overcome some limitations of capsule endoscopy. At the present time, in the majority of clinical conditions （i.e. obscure GI bleeding）, the winning strategy seems to be to couple these two techniques to explore the small bowel in a painless, safe and complete way （with capsule endoscopy） and to define and treat the lesions identified （with double balloon enteroscopy）.
基金co-supported by the National Basic Research Program of China (No. 623125020103)
文摘Aeromagnetic interference could not be compensated effectively if the precision of parameters which are solved by the aircraft magnetic field model is low. In order to improve the compensation effect under this condition, a method based on small signal model and least mean square（LMS） algorithm is proposed. According to the method, the initial values of adaptive filter＇s weight vector are calculated with the solved model parameters through small signal model at first,then the small amount of direction cosine and its derivative are set as the input of the filter, and the small amount of the interference is set as the filter＇s expected vector. After that, the aircraft magnetic interference is compensated by LMS algorithm. Finally, the method is verified by simulation and experiment. The result shows that the compensation effect can be improved obviously by the LMS algorithm when original solved parameters have low precision. The method can further improve the compensation effect even if the solved parameters have high precision.
文摘Aqueous extracts from various plant parts of fenugreek(3%)(aerial parts:leaves and stems(LS),roots(R),ground seeds(GS)and not ground seeds(NGS))and petroleum ether,ethyl acetate and methanolic fractions of the aerial parts were assayed to determine their antifungal potential against Botrytis cinerea,Fusarium graminearum,Alternaria sp.,Pythium aphanidermatum,and Rhizoctinia solani.All fenugreek plant parts showed antifungal potential and the magnitude of their inhibitory effects was species and plant parts d...
文摘This orticle seeks to address come lingering debates within sustainability studies by revealing the connections between renewable energy consumption and sustainability.Using data from 30 OECD counties,examines the connections via regression and geospattal analysis.Findings from the quantitative analysis indicate that about 50% of the variation in Sustainability is accounted for by the degree of renewables Consumption. The geospatial analysis visuaUv illustrates the intimate connections between the two variables, Theoretically, renewable energy relates to sustainability in three dimensions. The first dimension is economic. Relying on traditional fassil fuels eventually will bring our economy to a stop. Renewable energies, however; are able to secure our energy supply into an indefinite future. The second dimension links to ethics. To leave an intact planet torture generations is a moral responsibity of our generation, The current energy supply system is built on depletion of natural resources, while the sources of renewable energy are vast and constantly replenished. Tire last dimension is ecologic. How to allocate a proper apportionment of the global biosphere between humankind and the other life on the earth is a critical issue related to sustainability. By using renewable energy, we can greatly reduce our impact on biodiversity and therefore strike a balance between humankind and other life. Overall the research suggests that developing renewables can and in many. cases does sustain a nation＇s economic growth while simultaneously protecting the environment. It is a win-win situation. This finding undoubtedly points out a practical and realistic path for sustainable development.
文摘The coronavirus disease 2019(COVID-19)pandemic has caused detrimental effects on many aspects of healthcare practice.Screening programs for the commonest malignancies,namely colorectal cancer(CRC),breast cancer and cervical cancer have been discontinued or interrupted since the beginning of restriction measures aimed to limit transmission of the new coronavirus infection.Robust evidence exists in favour of the role of screening campaigns in reducing mortality from CRC.In fact,the majority of pre-malignant lesions of the colon and rectum can be diagnosed with colonoscopy and treated by endoscopic or surgical resection.Besides,colonoscopy screening allows the diagnosis of CRCs in their pre-clinical stage.Italy was one of the first European countries where a high level of COVID-19 infections and deaths was observed,and one of the first where lockdowns and strict measures were adopted to reduce the risk of COVID-19 diffusion among the population.A systematic review of the literature was performed,including the PubMed,Scopus,Web of Sciences,and Reference Citation Analysis databases,with the aim of critically evaluating the impact of the COVID-19 pandemic on CRC screening in Italy.We found that reduction of CRC screening activity surpassed 50%in most endoscopic units,with almost 600000 fewer CRC screening exams conducted in the first 5 mo of 2020 vs the same period of 2019.While the consequences of the discontinuation of endoscopy screening for the prognosis and mortality of CRC will be evident in the next few years,recent data confirm that CRC is currently treated at a more advanced stage than in the pre-COVID-19 era.Since delays in CRC prevention and early diagnosis may translate to increased CRC-specific mortality,world healthcare systems should adopt strategies to maintain the regularity of CRC screening during subsequent peaks of the COVID-19 pandemic,or future events that might hamper screening programs.
文摘The organization of coordinated attack and the selection of aiming point which affect hit probability were analyzed for the countermeasures taken by the hostile submarines at two helicopters' coordinated attack.A computational model of coordinated attack parameters,a model of submarine maneuver,and a model of noise jammer were established.Compared to single helicopter' torpedo attack,the coordinated attack of two helicopters can effectively increase the hit probability of torpedo and achieve the higher target detecting probability under counterwork condition.
文摘Background.Although cerebral auto somal dominant arte-riopathy with subcortical infarcts and leukoencephalopathy(CADASIL)is considered a cerebrovascular dis order with almost exclusively neurological sy mptoms,the arteriopathy is generalized and involves choroid al and retinal vascula-ture as demonstrated by fluorescein angiographic and oc-ular electrophysiological abnorma lities.The occurrence of acute visual loss due to nonarteritic anterior ischemic optic neuropathy(NAION)has not previously been reported in CADASIL.Objective:To describe acu te visual loss due to NAION as a possible manifestation of CADASIL.Patients and Methods:The patient was a 60-year-old man with subcortical diffuse leukoencephalopathy,multi-infarct de-mentia,tetraparesis,visual loss,and a family history of stroke.We performed clinical and neuroophthalmological evaluation,electrophysiological assessment,brain mag-netic resonance imaging,and geneti c screening for muta-tions or small deletions of the Notch3gene,(causing CADASIL).Results:The patient ’s first symptom was a-cute visual loss in the right eye due t o NAION at age 27years,in absence of the common cardi ovascular risk fac-tors and before any neurological imp airment.The patient was reevaluated at age 60years,and n eu-ro-ophthalmological examination s howed optic disc atrophy in the right eye with arteriolar narrowing and a reduction in visual acuity in the left eye.Fluorescein angiography ofthe right eye showed evidence of pers istent peripapillary hypofluorescence with a retinal pig ment epithelial windows defect in the inferior temporal area.Pattern reversal visual evoked potentials were abolished in the right eye.The P100latency of the left eye was delay ed and reduced in amplitude.The diagnosis of CADASIL was confirmed by molecular analysis(heterozygotes for the C406T mutatio n on exon 3of the Notch3gene).There was a family history of cerebrovascular disorders and ocular impairment.Con-clusions:Visual loss due to transie nt or stable ischemic events involving the optic nerve hea d should be considered in the CADASIL phenotype.The possib ility of CADASIL should also be evaluated in patients with NAION who do not have cardiovascular risk factors but do have a family history of stroke.
文摘Use of iodinated skin disinfectants in the perinatal period can result in significant iodine overload of the neonate and transient hypothyroidism.The authors report a case of unusually severe hypothyroidism requiring l-thyroxine (L-T4) replacement therapy in a premature neonate after prolonged use of iodinated skin disinfectants for a complex skin lesion.Neonatal iodine overload should be minimized, and in cases with significant iodine exposure, thyroid-stimulating hormone should be monitored, especially in preterm neonates who are exquisitely sensitive to the antithyroid effects of iodine excess.
基金funded by the U.S. National Science Foundation (Crossref Funder ID: 100000001, ROR: https://ror.org/021nxhr62) Award 2134956
文摘Persistent identifiers for research objects, researchers, organizations, and funders are the key to creating unambiguous and persistent connections across the global research infrastructure(GRI). Many repositories are implementing mechanisms to collect and integrate these identifiers into their submission and record curation processes. This bodes well for a well-connected future, but metadata for existing resources submitted in the past are missing these identifiers, thus missing the connections required for inclusion in the connected infrastructure. Re-curation of these metadata is required to make these connections. This paper introduces the global research infrastructure and demonstrates how repositories, and their user communities, can contribute to and benefit from connections to the global research infrastructure. The Dryad Data Repository has existed since 2008 and has successfully re-curated the repository metadata several times, adding identifiers for research organizations, funders, and researchers. Understanding and quantifying these successes depends on measuring repository and identifier connectivity. Metrics are described and applied to the entire repository here. Identifiers(Digital Object Identifiers, DOIs) for papers connected to datasets in Dryad have long been a critical part of the Dryad metadata creation and curation processes. Since 2019, the portion of datasets with connected papers has decreased from 100% to less than 40%. This decrease has significant ramifications for the re-curation efforts described above as connected papers have been an important source of metadata. In addition, missing connections to papers make understanding and re-using datasets more difficult. Connections between datasets and papers can be difficult to make because of time lags between submission and publication, lack of clear mechanisms for citing datasets and other research objects from papers, changing focus of researchers, and other obstacles. The Dryad community of members, i.e. users, research institutions, publishers, and funders have vested interests in identifying these connections and critical roles in the curation and re-curation efforts. Their engagement will be critical in building on the successes Dryad has already achieved and ensuring sustainable connectivity in the future.
文摘Oleosin, caleosin and steroleosin are normally expressed in developing seed cells and are targeted to oil bodies. In the present work, the cDNA of each gene tagged with fluorescent proteins was transiently expressed into tobacco protoplasts and the fluorescent patterns observed by confocal laser scanning microscopy. Our results indicated clear differences in the endocellular localization of the three proteins. Oleosin and caleosin both share a common structure consisting of a central hydrophobic domain flanked by two hydrophilic domains and were correctly targeted to lipid droplets （LD）, whereas steroleosin, characterized by an N-terminal oil body anchoring domain, was mainly retained in the endoplasmic reticulum （ER）. Protoplast fractionation on sucrose gradients indicated that both oleosin and caleosin- green fluorescent protein （GFP） peaked at different fractions than where steroleosin-GFP or the ER marker binding immunoglobulin protein （BiP）, were recovered. Chemical analysis confirmed the presence of triacylglycerols in one of the fractions where oleosin-GFP was recovered. Finally, only oleosin- and caleosin-GFP were able to reconstitute artificial oil bodies in the presence of triacylglycerols and phospholipids. Taken together, our results pointed out for the first time that leaf LDs can be separated by the ER and both oleosin or caleosin are selectively targeted due to the existence of selective mechanisms controlling protein association with these organelles.
基金the Korea Electrotechnology Research Institute(KERI)Primary Research Program through the National Research Council of Science and Technology(NST),funded by the Ministry of Science and ICT(MSIT)(No.23A01032).
文摘Piezoelectricity offers an electromechanical coupling that is widely utilized in transducer applications.There has been a consistent demand for transparent piezoelectric materials for optoelectrical applications.Therefore,despite the inherent tradeoff between the transparency and the piezoelectricity,numerous strategies have been explored to develop the transparent piezoelectric materials.Nonetheless,the most transparent piezoelectric materials developed to date is either a single crystal or materials that achieve transparency via hot-press sintering,limiting its industrial applicability.Therefore,we introduce a novel piezoelectric material that ensures transparency through co-doping and pressureless sintering of polycrystalline ceramics.In this study,we employed a compositional optimization approach to enhance the synergistic effect between the transparency and the piezoelectric properties of 0.71Pb(Mg_(1/3)Nb_(2/3))O_(3)–0.29PbTiO_(3)(PMN–0.29PT)ceramics.By utilizing the tape casting process for mass production and large-area manufacturing,our Pb_(0.913)La_(0.0145)Sm_(0.0145)(Mg_(1/3)Nb_(2/3))_(0.71)Ti_(0.29)O_(3)(TP2.9)ceramics exhibited over 60%transparency and large piezoelectric coefficient(d33)of 1104 pC/N.This material holds considerable promise for a wide range of industrial applications in both the optical and electronic domains.
文摘On October 26-28,2005,in Pittsburgh,PA,key members of the building industry,green design community,healthcare industry,academic institutions,and government agencies gathered in a targeted dialogue to consider the feasibility of forming a consortium to improve how healthcare facilities are planned,designed,constructed,and maintained.The roundtable formally documented the drivers and expectations of participants;instinctual,emotional,and intellectual reactions of participants to healthcare facilities greening;and the strengths,opportunities,and challenges posed by the task of greening healthcare facilities.Three areas of consensus emerged clearly from the discussion:(a)All participants supported the formation of a consortium focused on the greening of healthcare facilities;(b)All believed the mix of expertise will make this consortium unique;and(c)All believed that the development of a shared research agenda among the building industry,healthcare providers,and academia is vital.The proposed greening healthcare consortium envisions:(1)Providing a network for sharing existing research and findings related to greening of healthcare facilities;(2)Facilitating collaboration between healthcare projects,current research,and hospital performance data;and(3)Providing an informed basis for healthcare design and construction decision-making.Based on input from the roundtable discussions,eight research thrusts were identified that the proposed consortium would be ideally positioned to address based on the competencies and positions of the members.These eight research thrusts are:(1)establishing the relationships between facilities and clinical outcome;(2)defining costvalue relationships regarding green building;(3)understanding the basis for decision making;(4)compiling a data repository;(5)developing active and passive research methods;(6)investigating interdependencies;(7)minimizing or eliminating waste;and(8)implementing research.The active inter-industry discourse promoted by this consortium between the healthcare industry,building industry,and academic institutions allows for a unique dynamic to be harnessed between the“physiology”of healthcare and the“physics”of healthcare facilities.This will enable the delivery of healthcare projects and the quality of healthcare to be continuously improved and enhanced.The operational framework for the proposed consortium would rely on projects from the building and healthcare industries serving as case studies for gathering information and incorporating the developments of research at academic institutions.
文摘Sustainable building projects have levels of complexity over conventional building projects that challenge current projectmanagement tools at efficiently managing the rigors of sustainable projects.The Continuous Value EnhancementProcess(CVEP)is a recently developed tool designed specifically for sustainable building projects.This project managementtool enables project teams to systematically generate and evaluate project alternatives for meeting sustainable goals.The goal of this tool is to identify high performance solutions that increase levels of sustainability and improve projectperformance.CVEP was experimentally implemented and tested on four case study projects to evaluate its ability tosupport project management decision making in ways that elevate sustainability and project performance.Reported inthis paper,the results show CVEP produced first cost and life cycle cost savings.In particular,the study confirms thatCVEP has the capability to:1.)Provide a systematic evaluation process,2.)Collect high performance building solutions,and 3.)Be applicable to different project types.These results show that it is possible to employ targeted projectmanagement techniques,like CVEP,to improve the cost-effective provision of sustainable buildings.
