As a rare earth solute element in Mg alloys,Y has the beneficial effects of increasing both the strength and the ductility as well as weakening the crystallographic texture.To achieve a more fundamental understanding ...As a rare earth solute element in Mg alloys,Y has the beneficial effects of increasing both the strength and the ductility as well as weakening the crystallographic texture.To achieve a more fundamental understanding on how Y addition affects the microstructural evolution and mechanical properties,the Y segregation behavior at grain boundaries was investigated in Mg-1wt.%Y and Mg-7wt.%Y alloys at different conditions.The segregation intensity and its dependence on the grain boundary misorientation angle were experimentally characterized and computationally predicted.Strong segregation at grain boundaries was observed in both low and high Y-containing alloys.Y segregation was found to remain in alloy Mg-7Y after high-temperature annealing heat treatment at 540℃.No direct correlation between the Y segregation intensity and the grain boundary misorientation angle could be established based on either the experimental characterization or the atomistic simulation with a spectral model.We thus conclude that grain boundary segregation of Y is independent of grain boundary misorientation angle.展开更多
AIM:To review the benefits of single photon emission computed tomography(SPECT)/computed tomography(CT)hybrid imaging for diagnosis of various endocrine disorders.METHODS:We performed MEDLINE and Pub Med searches usin...AIM:To review the benefits of single photon emission computed tomography(SPECT)/computed tomography(CT)hybrid imaging for diagnosis of various endocrine disorders.METHODS:We performed MEDLINE and Pub Med searches using the terms:"SPECT/CT";"functional anatomic mapping";"transmission emission tomography";"parathyroid adenoma";"thyroid cancer";"neuroendocrine tumor";"adrenal";"pheochromocytoma";"paraganglioma";in order to identify relevant articles published in English during the years 2003 to 2015.Reference lists from the articles were reviewed to identify additional pertinent articles.Retrieved manuscripts(case reports,reviews,meta-analyses and abstracts)concerning the application of SPECT/CT to endocrine imaging were analyzed to provide a descriptive synthesis of the utility of this technology.RESULTS:The emergence of hybrid SPECT/CT camera technology now allows simultaneous acquisition of combined multi-modality imaging,with seamless fusion of three-dimensional volume datasets.The usefulness of combining functional information to depict the biodistribution of radiotracers that map cellular processes of the endocrine system and tumors of endocrine origin,with anatomy derived from CT,has improved the diagnostic capability of scintigraphy for a range of disorders of endocrine gland function.The literature describes benefits of SPECT/CT for^(99m)Tc-sestamibi parathyroid scintigraphy and^(99m)Tc-pertechnetate thyroid scintigraphy,^(123)I-or^(131)I-radioiodine for staging of differentiated thyroid carcinoma,^(111)In-and^(99m)Tclabeled somatostatin receptor analogues for detection of neuroendocrine tumors,^(131)I-norcholesterol(NP-59)scans for assessment of adrenal cortical hyperfunction,and^(123)I-or^(131)I-metaiodobenzylguanidine imaging for evaluation of pheochromocytoma and paraganglioma.CONCLUSION:SPECT/CT exploits the synergism between the functional information from radiopharmaceutical imaging and anatomy from CT,translating to improved diagnostic accuracy and meaningful impact on patient care.展开更多
Black carbon(BC)is considered the second largest anthropogenic climate forcer,but the radiative effects of BC are highly correlated with its combustion sources.On-road vehicles are an important source of anthropogenic...Black carbon(BC)is considered the second largest anthropogenic climate forcer,but the radiative effects of BC are highly correlated with its combustion sources.On-road vehicles are an important source of anthropogenic BC.However,there are major uncertainties in the estimates of the BC emissions from on-road light-duty passenger vehicles(LDPVs),and results obtained with the portable emissions measurement system(PEMS)method are particularly lacking.We developed a PEMS platform and evaluated the on-road BC emissions from ten in-use LDPVs.We demonstrated that the BC emission factors(EFs)of gasoline direction injection(GDI)engine vehicles range from 1.10 to 1.56 mg.km^(-1),which are higher than the EFs of port fuel injection(PFI)engine vehicles(0.10–0.17 mg.km^(-1))by a factor of 11.The BC emissions during the cold-start phase contributed 2%–33%to the total emissions.A strong correlation(R^(2)=0.70)was observed between the relative BC EFs and average vehicle speed,indicating that traffic congestion alleviation could effectively mitigate BC emissions.Moreover,BC and particle number(PN)emissions were linearly correlated(R^(2)=0.90),and compared to PFI engine vehicles,the instantaneous PN-to-BC emission rates of GDI engine vehicles were less sensitive to vehicle specific power-to-velocity(VSPV)increase in all speed ranges.展开更多
BACKGROUND Elective cholecystectomy(CCY)is recommended for patients with gallstone-related acute cholangitis(AC)following endoscopic decompression to prevent recurrent biliary events.However,the optimal timing and imp...BACKGROUND Elective cholecystectomy(CCY)is recommended for patients with gallstone-related acute cholangitis(AC)following endoscopic decompression to prevent recurrent biliary events.However,the optimal timing and implications of CCY remain unclear.AIM To examine the impact of same-admission CCY compared to interval CCY on patients with gallstone-related AC using the National Readmission Database(NRD).METHODS We queried the NRD to identify all gallstone-related AC hospitalizations in adult patients with and without the same admission CCY between 2016 and 2020.Our primary outcome was all-cause 30-d readmission rates,and secondary outcomes included in-hospital mortality,length of stay(LOS),and hospitalization cost.RESULTS Among the 124964 gallstone-related AC hospitalizations,only 14.67%underwent the same admission CCY.The all-cause 30-d readmissions in the same admission CCY group were almost half that of the non-CCY group(5.56%vs 11.50%).Patients in the same admission CCY group had a longer mean LOS and higher hospitalization costs attrib-utable to surgery.Although the most common reason for readmission was sepsis in both groups,the second most common reason was AC in the interval CCY group.CONCLUSION Our study suggests that patients with gallstone-related AC who do not undergo the same admission CCY have twice the risk of readmission compared to those who undergo CCY during the same admission.These readmis-sions can potentially be prevented by performing same-admission CCY in appropriate patients,which may reduce subsequent hospitalization costs secondary to readmissions.展开更多
General guidelines for the design of ligands for the enrichment of rare-earth elements by solid-liquid adsorption are described using coordination chemistry.Relevant properties of ligands include selectivity of metal ...General guidelines for the design of ligands for the enrichment of rare-earth elements by solid-liquid adsorption are described using coordination chemistry.Relevant properties of ligands include selectivity of metal ions based on adjustment of donor atom polarizability,denticity,and the pKarange of the binding sites.The selectivity of solid-phase materials for the enrichment of rare-earth ions by the ligand design guidelines is outlined,with special consideration of additional variable factors including steric hindrance,saturated binding sites,variability in speciation caused by the identity of counterions and ionic strength,and size-exclusivity in ligands stemming from differences in bite angle,preo rganization of ligands,or intraligand interactions.This review analyzes some principles of selectivity of rare-earth elements with ligands organized by donor type from examples collected from reports published between 2009 and 2021.展开更多
The use of fluorodeoxyglucose positron emission to-mography(FDG PET) scan technology in the manage-ment of head and neck cancers continues to increase. We discuss the biology of FDG uptake in malignant lesions and als...The use of fluorodeoxyglucose positron emission to-mography(FDG PET) scan technology in the manage-ment of head and neck cancers continues to increase. We discuss the biology of FDG uptake in malignant lesions and also discuss the physics of PET imaging. The various parameters described to quantify FDG up-take in cancers including standardized uptake value, metabolic tumor volume and total lesion glycolysis are presented. PET scans have found a significant role in the diagnosis and staging of head and neck cancers. They are also being increasingly used in radiation ther-apy treatment planning. Many groups have also used PET derived values to serve as prognostic indicators of outcomes including loco-regional control and overall survival. FDG PET scans are also proving very useful in assessing the efficacy of treatment and management and follow-up of head and neck cancer patients. This review article focuses on the role of FDG-PET com-puted tomography scans in these areas for squamous cell carcinoma of the head and neck. We present the current state of the art and speculate on the future applications of this technology including protocol de-velopment, newer imaging methods such as combinedmagnetic resonance and PET imaging and novel ra-diopharmaceuticals that can be used to further study tumor biology.展开更多
The Yangtze River Delta（YRD） region is one of the most prosperous and densely populated regions in China and is facing tremendous pressure to mitigate vehicle emissions and improve air quality.Our assessment has rev...The Yangtze River Delta（YRD） region is one of the most prosperous and densely populated regions in China and is facing tremendous pressure to mitigate vehicle emissions and improve air quality.Our assessment has revealed that mitigating vehicle emissions of NOx would be more difficult than reducing the emissions of other major vehicular pollutants（e.g.,CO,HC and PM_（2.5）） in the YRD region.Even in Shanghai,where the emission control implemented are more stringent than in Jiangsu and Zhejiang,we observed little to no reduction in NOx emissions from 2000 to 2010.Emission-reduction targets for HC,NOx and PM_（2.5） are determined using a response surface modeling tool for better air quality.We design city-specific emission control strategies for three vehicle-populated cities in the YRD region：Shanghai and Nanjing and Wuxi in Jiangsu.Our results indicate that even if stringent emission control consisting of the Euro 6/VI standards,the limitation of vehicle population and usage,and the scrappage of older vehicles is applied,Nanjing and Wuxi will not be able to meet the NOx emissions target by 2020.Therefore,additional control measures are proposed for Nanjing and Wuxi to further mitigate NOx emissions from heavy-duty diesel vehicles.展开更多
Subgroup J avian leukosis virus(ALV-J) is a highly oncogenic retrovirus that has been devastating the global poultry industry since the late 1990s. The major infection model of ALV-J is vertical transmission, which is...Subgroup J avian leukosis virus(ALV-J) is a highly oncogenic retrovirus that has been devastating the global poultry industry since the late 1990s. The major infection model of ALV-J is vertical transmission, which is responsible for the congenital infection of progeny from generation to generation. Increasing evidence has suggested that extracellular vesicles(EVs) derived from virus-infected cells or biological fluids have been thought to be vehicles of transmission for viruses. However, the role of EVs in infection and transmission of ALV-J remains obscure. In the present study, semen extracellular vesicles(SE) were isolated and purified from ALV-J-infected rooster seminal plasma(SE-ALV-J), which was shown to contain ALV-J genomic RNA and partial viral proteins, as determined by RNA sequencing, reverse transcription-quantitative PCR and Western blotting. Furthermore, SE-ALV-J was proved to be able to transmit ALV-J infection to host cells and establish productive infection.More importantly, artificial insemination experiments showed that SE-ALV-J transmitted ALV-J infection to SPF hens, and subsequently mediated vertical transmission of ALV-J from the SPF hens to the progeny chicks. Taken together, the results of the present study suggested that ALV-J utilized host semen extracellular vesicles as a novel means for vertical transmission, enhancing our understanding on mechanisms underlying ALV-J transmission.展开更多
Locating the source of decametric(DAM)radio emissions is a key step in the use of remote radio observations to understand the Jovian magnetospheric dynamics and their interaction with the planet’s moons.Wang YM et al...Locating the source of decametric(DAM)radio emissions is a key step in the use of remote radio observations to understand the Jovian magnetospheric dynamics and their interaction with the planet’s moons.Wang YM et al.(2020)presented a method by which recorded arc-shaped DAM emissions in the radio dynamic spectra can be used to locate the source of a DAM.An Io-related DAM event on March 14,2014 was used to demonstrate the method.A key parameter in the method is whether the DAM is emitted in the northern or the southern hemisphere;the hemisphere of origin can be determined definitively from the polarization of the emission.Unfortunately,polarization information for the emission on March 14,2014 event was not recorded.Our analysis assumed the source to be in the northern hemisphere.Lamy et al.(2022)argue convincingly that the source was probably in the southern hemisphere.We appreciate the helpful contribution of Lamy et al.(2022)to this discussion and have updated our analysis,this time assuming that the DAM source was in the southern hemisphere.We also explore the sensitivity of our method to another parameter-the height at which the value of fce,max,which is the maximal electron cyclotron frequency reached along the active magnetic flux tube,is adopted.Finally,we introduce our recent statistical study of 68 DAM events,which lays a more solid basis for testing the reliability of our method,which we continue to suggest is a promising tool by which remote radio observations can be used to locate the emission source of Jovian DAMs.展开更多
Decametric(DAM) radio emissions are one of the main windows through which one can reveal and understand the Jovian magnetospheric dynamics and its interaction with the moons. DAMs are generated by energetic electrons ...Decametric(DAM) radio emissions are one of the main windows through which one can reveal and understand the Jovian magnetospheric dynamics and its interaction with the moons. DAMs are generated by energetic electrons through cyclotron-maser instability. For Io(the most active moon) related DAMs, the energetic electrons are sourced from Io volcanic activities, and quickly trapped by neighboring Jovian magnetic field. To properly interpret the physical processes behind DAMs, it is important to precisely locate the source field lines from which DAMs are emitted. Following the work by Hess et al.(2008, 2010), we develop a method to locate the source region as well as the associated field lines for any given DAM emission recorded in a radio dynamic spectrum by, e.g.,Wind/WAVES or STEREO/WAVES. The field lines are calculated by the state-of-art analytical model, called JRM09(Connerney et al., 2018).By using this method, we may also derive the emission cone angle and the energy of associated electrons. If multiple radio instruments at different perspectives observe the same DAM event, the evolution of its source region and associated field lines is able to be revealed. We apply the method to an Io-DAM event, and find that the method is valid and reliable. Some physical processes behind the DAM event are also discussed.展开更多
BACKGROUND The prevalence of Crohn’s disease(CD)and ulcerative colitis(UC)is on the rise worldwide.This rising prevalence is concerning as patients with CD and UC may frequently relapse leading to recurrent hospitali...BACKGROUND The prevalence of Crohn’s disease(CD)and ulcerative colitis(UC)is on the rise worldwide.This rising prevalence is concerning as patients with CD and UC may frequently relapse leading to recurrent hospitalizations and increased healthcare utilization.AIM To identify trends and adverse outcomes for 30 d readmissions for CD and UC.METHODS This was a retrospective,interrupted trends study involving all adult(≥18 years)30 d readmissions of CD and UC from the National Readmission Database(NRD)between 2008 and 2018.Patients<18 years,elective,and traumatic hospitalizations were excluded from this study.We identified hospitalization characteristics and readmission rates for each calendar year.Trends of inpatient mortality,mean length of hospital stay(LOS)and mean total hospital cost(THC)were calculated using a multivariate logistic trend analysis adjusting for age,gender,insurance status,comorbidity burden and hospital factors.Furthermore,trends between CD and UC readmissions were compared using regression of the interaction coefficient after adjusting for age and gender to determine relative trends between the two populations.Stata®Version 16 software(StataCorp,TX,United States)was used for statistical analysis and P value≤0.05 were considered statistically significant.RESULTS Total number of 30 d readmissions increased from 6202 in 2010 to 7672 in 2018 for CD and from 3272 in 2010 to 4234 in 2018 for UC.We noted increasing trends for 30-day all-cause readmission rate of CD from 14.9%in 2010 to 17.6%in 2018(P-trend<0.001),CD specific readmission rate from 7.1%in 2010 to 8.2%in 2018(P-trend<0.001),30-day all-cause readmission rate of UC from 14.1%in 2010 to 15.7%in 2018(P-trend=0.003),and UC specific readmission rate from 5.2%in 2010 to 5.6%in 2018(P-trend=0.029).There was no change in the risk adjusted trends of inpatient mortality and mean LOS for CD and UC readmissions.However,we found an increasing trend of mean THC for UC readmissions.After comparison,there was no statistical difference in the trends for 30 d all-cause readmission rate,inpatient mortality,and mean LOS between CD and UC readmissions.CONCLUSION There was an increase in total number of 30 d readmissions for CD and UC with a trend towards increasing 30 d all-cause readmission rates.展开更多
Background: The Implantable Cardiac Monitor (ICM) is an invaluable tool for detecting cardiac arrhythmias by providing physicians. Critical to the success of ICMs depends on how quickly and accurately the data can be ...Background: The Implantable Cardiac Monitor (ICM) is an invaluable tool for detecting cardiac arrhythmias by providing physicians. Critical to the success of ICMs depends on how quickly and accurately the data can be transmitted to a physician’s office after an arrhythmic event. Then, the clinical event can be analyzed and the treatment will be provided accordingly. However, no reports have been published as to how efficiently the ICM data is transmitted. Methods: There is a retrospective review of 520 patients who received a Medtronic Reveal LINQTM between 2/01/2015 and 6/01/2017. The time from the arrhythmic event to the time of physician notification was calculated and reason for delay was noted. Results: One hundred and twenty patients out of 520 patients (23%) had arrhythmic events transmitted over a mean follow up of 14 ± 4 months. The mean time between cardiac events and physician notification was 15 ± 8 days. Sixty-three percent (63%) of data transmission delay (defined as >24 hours) was due to the MyCareLinkTM Monitor not being in proximity to the patient. Connection failure between the monitor and the network accounted for 34% of data transmission delay. Conclusion: Significant delay in data transmission from Medtronic Reveal LINQTM cardiac monitor occurs frequently impacting patient care. Newer generations of the implantable cardiac monitors utilize Bluetooth technology, enabling immediate transfer of data from ICM to a patient’s cellular phone and subsequently to their physician’s office. This technology could potentially improve efficiency and reliability eliminating the issues of proximity and connectivity.展开更多
BACKGROUND Alcoholic liver cirrhosis(ALC)is a chronic liver disease with varying disease severity.Readmissions of ALC are associated with poor outcomes.AIM To identify and assess trends of readmissions for ALC over an...BACKGROUND Alcoholic liver cirrhosis(ALC)is a chronic liver disease with varying disease severity.Readmissions of ALC are associated with poor outcomes.AIM To identify and assess trends of readmissions for ALC over an eight-year period.METHODS This retrospective interrupted trend study analysed 30-d readmissions of ALC in the United States from 2010 to 2018 using the National Readmissions Database.Hospitalization for ALC was the reason for index admission obtained using the International Classification of Diseases codes(571.2 and K70.3X).Biodemographic characteristics and hospitalization trends were highlighted over time.A multivariate regression analysis model was used to calculate the trend for riskadjusted odds of 30-d all-cause ALC readmissions,ALC specific readmission rate,ALC readmission proportion,inpatient mortality,mean length of stay(LOS)and mean total hospital cost(THC)following adjustments for age,gender,grouped Charlson Comorbidity Index,insurance,mean household income,and hospital characteristics.RESULTS There was a trend towards increasing total 30-d readmissions of ALC from 7660 in 2010 to 15085 in 2018(P<0.001).Patients readmitted for ALC were noted to have an increasing comorbidity burden over time.We noted a rise in the risk-adjusted 30-d all-cause readmission of ALC from 24.9%in 2010 to 29.9%in 2018(P<0.001).ALC-specific readmission rate increased from 6.3%in 2010 to 8.4%in 2018(P<0.001)while ALC readmission proportion increased from 31.4%in 2010 to 36.3%in 2018(P<0.001).Inpatient mortality for 30-d readmissions of ALC declined from 10.5%in 2010 to 8.2%in 2018(P=0.0079).However,there was a trend towards increasing LOS from 5.6 d in 2010 to 6.3 d in 2018(P<0.001)and increasing THC from 13790 dollars in 2010 to 17150 dollars in 2018(P<0.001).The total days of hospital stay attributable to 30-d readmissions of ALC increased by 119.2%while the total attributable hospital costs increased by 149%by the end of 2018.CONCLUSION There was an increase in the 30-d readmission rate and comorbidity burden for ALC;however,inpatient mortality declined.Additionally,there was a trend towards increasing LOS and THC for these readmissions.展开更多
Background: Despite efforts to expand prevention of mother-to-child transmission (PMTCT) of HIV in resource-limited settings, only 53% of women in sub-Saharan Africa receive adequate PMTCT services. Understanding fact...Background: Despite efforts to expand prevention of mother-to-child transmission (PMTCT) of HIV in resource-limited settings, only 53% of women in sub-Saharan Africa receive adequate PMTCT services. Understanding factors that enable successful program completion are crucial to improving adherence rates to PMTCT programs in these settings. Using a positive deviance approach, we explored patient and provider’s perspectives on factors enabling women to successfully access and adhere to PMTCT services to identify areas of program improvement and further reduce HIV transmission. Methods: Semi-structured interviews were conducted with 11 health care workers (HCWs) at two health centers in Kara, Togo and 34 women who had successfully completed the PMTCT program at those facilities. Women were identified using purposive sampling and content theme analysis was used to analyze the data. Results: Knowledge and belief in the potential to give birth to an HIV-negative child, supported by facilitating factors on the individual and community levels, was the cornerstone to women’s PMTCT program success. Effective program education and peer-to-peer interactions fostered the participants’ knowledge and belief in PMTCT, with the resulting internal motivation driving continued participation and adherence. The welcoming environment, availability of peer support groups and financial assistance from the health facility, further facilitated success, with women using this facility-based community to seek advice and support from HCWs and peers. Financial, physical, and emotional support from relatives was also important in ensuring unhindered access. Finally, the faith-based communities’ acceptance and support for HIV-positive women further encouraged participants to adhere to the program. Conclusion: Understanding and believing in the ability to have an HIV-negative baby was the most important facilitator for PMTCT program adherence. This led to internal motivation that was continually reinforced through facility and community supportive environments focused on addressing barriers. Efforts to improve PMTCT success should focus on all of these factors through a patient-centered approach.展开更多
Wireless sensor networks(WSNs)are projected to have a wide range of applications in the future.The fundamental problem with WSN is that it has afinite lifespan.Clustering a network is a common strategy for increasing t...Wireless sensor networks(WSNs)are projected to have a wide range of applications in the future.The fundamental problem with WSN is that it has afinite lifespan.Clustering a network is a common strategy for increasing the life-time of WSNs and,as a result,allowing for faster data transmission.The cluster-ing algorithm’s goal is to select the best cluster head(CH).In the existing system,Hybrid grey wolf sunflower optimization algorithm(HGWSFO)and optimal clus-ter head selection method is used.It does not provide better competence and out-put in the network.Therefore,the proposed Hybrid Grey Wolf Ant Colony Optimisation(HGWACO)algorithm is used for reducing the energy utilization and enhances the lifespan of the network.Black hole method is used for selecting the cluster heads(CHs).The ant colony optimization(ACO)technique is used tofind the route among origin CH and destination.The open cache of nodes,trans-mission power,and proximity are used to improve the CH selection.The grey wolf optimisation(GWO)technique is the most recent and well-known optimiser module which deals with grey wolves’hunting activity(GWs).These GWs have the ability to track down and encircle food.The GWO method was inspired by this hunting habit.The proposed HGWACO improves the duration of the net-work,minimizes the power consumption,also it works with the large-scale net-works.The HGWACO method achieves 25.64%of residual energy,25.64%of alive nodes,40.65%of dead nodes also it enhances the lifetime of the network.展开更多
基金supported by PRISMS(PRedictive Integrated Structural Materials Science)center which is located at University of Michigan and funded by U.S.Department of Energy,Office of Basic Energy Science,Division of Materials Science and Engineering(Grant award number DE-SC0008637)support from Michigan Center for Materials Characterization(MC2)at University of Michigan and Canmet MATERIALS,Natural Resources Canada+1 种基金the Extreme Science and Engineering Discovery Environment(XSEDE)Stampede2 at the TACC through allocation TG-MSS160003the National Energy Research Scientific Computing Center(NERSC),a U.S.Department of Energy Office of Science User Facility operated under Contract No.DE-AC02-05CH11231。
文摘As a rare earth solute element in Mg alloys,Y has the beneficial effects of increasing both the strength and the ductility as well as weakening the crystallographic texture.To achieve a more fundamental understanding on how Y addition affects the microstructural evolution and mechanical properties,the Y segregation behavior at grain boundaries was investigated in Mg-1wt.%Y and Mg-7wt.%Y alloys at different conditions.The segregation intensity and its dependence on the grain boundary misorientation angle were experimentally characterized and computationally predicted.Strong segregation at grain boundaries was observed in both low and high Y-containing alloys.Y segregation was found to remain in alloy Mg-7Y after high-temperature annealing heat treatment at 540℃.No direct correlation between the Y segregation intensity and the grain boundary misorientation angle could be established based on either the experimental characterization or the atomistic simulation with a spectral model.We thus conclude that grain boundary segregation of Y is independent of grain boundary misorientation angle.
文摘AIM:To review the benefits of single photon emission computed tomography(SPECT)/computed tomography(CT)hybrid imaging for diagnosis of various endocrine disorders.METHODS:We performed MEDLINE and Pub Med searches using the terms:"SPECT/CT";"functional anatomic mapping";"transmission emission tomography";"parathyroid adenoma";"thyroid cancer";"neuroendocrine tumor";"adrenal";"pheochromocytoma";"paraganglioma";in order to identify relevant articles published in English during the years 2003 to 2015.Reference lists from the articles were reviewed to identify additional pertinent articles.Retrieved manuscripts(case reports,reviews,meta-analyses and abstracts)concerning the application of SPECT/CT to endocrine imaging were analyzed to provide a descriptive synthesis of the utility of this technology.RESULTS:The emergence of hybrid SPECT/CT camera technology now allows simultaneous acquisition of combined multi-modality imaging,with seamless fusion of three-dimensional volume datasets.The usefulness of combining functional information to depict the biodistribution of radiotracers that map cellular processes of the endocrine system and tumors of endocrine origin,with anatomy derived from CT,has improved the diagnostic capability of scintigraphy for a range of disorders of endocrine gland function.The literature describes benefits of SPECT/CT for^(99m)Tc-sestamibi parathyroid scintigraphy and^(99m)Tc-pertechnetate thyroid scintigraphy,^(123)I-or^(131)I-radioiodine for staging of differentiated thyroid carcinoma,^(111)In-and^(99m)Tclabeled somatostatin receptor analogues for detection of neuroendocrine tumors,^(131)I-norcholesterol(NP-59)scans for assessment of adrenal cortical hyperfunction,and^(123)I-or^(131)I-metaiodobenzylguanidine imaging for evaluation of pheochromocytoma and paraganglioma.CONCLUSION:SPECT/CT exploits the synergism between the functional information from radiopharmaceutical imaging and anatomy from CT,translating to improved diagnostic accuracy and meaningful impact on patient care.
基金supported by the National Natural Science Foundation of China(51708327 and 51978404)。
文摘Black carbon(BC)is considered the second largest anthropogenic climate forcer,but the radiative effects of BC are highly correlated with its combustion sources.On-road vehicles are an important source of anthropogenic BC.However,there are major uncertainties in the estimates of the BC emissions from on-road light-duty passenger vehicles(LDPVs),and results obtained with the portable emissions measurement system(PEMS)method are particularly lacking.We developed a PEMS platform and evaluated the on-road BC emissions from ten in-use LDPVs.We demonstrated that the BC emission factors(EFs)of gasoline direction injection(GDI)engine vehicles range from 1.10 to 1.56 mg.km^(-1),which are higher than the EFs of port fuel injection(PFI)engine vehicles(0.10–0.17 mg.km^(-1))by a factor of 11.The BC emissions during the cold-start phase contributed 2%–33%to the total emissions.A strong correlation(R^(2)=0.70)was observed between the relative BC EFs and average vehicle speed,indicating that traffic congestion alleviation could effectively mitigate BC emissions.Moreover,BC and particle number(PN)emissions were linearly correlated(R^(2)=0.90),and compared to PFI engine vehicles,the instantaneous PN-to-BC emission rates of GDI engine vehicles were less sensitive to vehicle specific power-to-velocity(VSPV)increase in all speed ranges.
文摘BACKGROUND Elective cholecystectomy(CCY)is recommended for patients with gallstone-related acute cholangitis(AC)following endoscopic decompression to prevent recurrent biliary events.However,the optimal timing and implications of CCY remain unclear.AIM To examine the impact of same-admission CCY compared to interval CCY on patients with gallstone-related AC using the National Readmission Database(NRD).METHODS We queried the NRD to identify all gallstone-related AC hospitalizations in adult patients with and without the same admission CCY between 2016 and 2020.Our primary outcome was all-cause 30-d readmission rates,and secondary outcomes included in-hospital mortality,length of stay(LOS),and hospitalization cost.RESULTS Among the 124964 gallstone-related AC hospitalizations,only 14.67%underwent the same admission CCY.The all-cause 30-d readmissions in the same admission CCY group were almost half that of the non-CCY group(5.56%vs 11.50%).Patients in the same admission CCY group had a longer mean LOS and higher hospitalization costs attrib-utable to surgery.Although the most common reason for readmission was sepsis in both groups,the second most common reason was AC in the interval CCY group.CONCLUSION Our study suggests that patients with gallstone-related AC who do not undergo the same admission CCY have twice the risk of readmission compared to those who undergo CCY during the same admission.These readmis-sions can potentially be prevented by performing same-admission CCY in appropriate patients,which may reduce subsequent hospitalization costs secondary to readmissions.
基金Project supported by the U.S.Army Engineer Research and Development Center (W912HZ-21-2-0048)。
文摘General guidelines for the design of ligands for the enrichment of rare-earth elements by solid-liquid adsorption are described using coordination chemistry.Relevant properties of ligands include selectivity of metal ions based on adjustment of donor atom polarizability,denticity,and the pKarange of the binding sites.The selectivity of solid-phase materials for the enrichment of rare-earth ions by the ligand design guidelines is outlined,with special consideration of additional variable factors including steric hindrance,saturated binding sites,variability in speciation caused by the identity of counterions and ionic strength,and size-exclusivity in ligands stemming from differences in bite angle,preo rganization of ligands,or intraligand interactions.This review analyzes some principles of selectivity of rare-earth elements with ligands organized by donor type from examples collected from reports published between 2009 and 2021.
文摘The use of fluorodeoxyglucose positron emission to-mography(FDG PET) scan technology in the manage-ment of head and neck cancers continues to increase. We discuss the biology of FDG uptake in malignant lesions and also discuss the physics of PET imaging. The various parameters described to quantify FDG up-take in cancers including standardized uptake value, metabolic tumor volume and total lesion glycolysis are presented. PET scans have found a significant role in the diagnosis and staging of head and neck cancers. They are also being increasingly used in radiation ther-apy treatment planning. Many groups have also used PET derived values to serve as prognostic indicators of outcomes including loco-regional control and overall survival. FDG PET scans are also proving very useful in assessing the efficacy of treatment and management and follow-up of head and neck cancer patients. This review article focuses on the role of FDG-PET com-puted tomography scans in these areas for squamous cell carcinoma of the head and neck. We present the current state of the art and speculate on the future applications of this technology including protocol de-velopment, newer imaging methods such as combinedmagnetic resonance and PET imaging and novel ra-diopharmaceuticals that can be used to further study tumor biology.
基金sponsored by the National Science&Technology Pillar Program of China(No.2013BAC13B03)the National Natural Science Foundation of China(Nos.51322804 and 91544222)
文摘The Yangtze River Delta（YRD） region is one of the most prosperous and densely populated regions in China and is facing tremendous pressure to mitigate vehicle emissions and improve air quality.Our assessment has revealed that mitigating vehicle emissions of NOx would be more difficult than reducing the emissions of other major vehicular pollutants（e.g.,CO,HC and PM_（2.5）） in the YRD region.Even in Shanghai,where the emission control implemented are more stringent than in Jiangsu and Zhejiang,we observed little to no reduction in NOx emissions from 2000 to 2010.Emission-reduction targets for HC,NOx and PM_（2.5） are determined using a response surface modeling tool for better air quality.We design city-specific emission control strategies for three vehicle-populated cities in the YRD region：Shanghai and Nanjing and Wuxi in Jiangsu.Our results indicate that even if stringent emission control consisting of the Euro 6/VI standards,the limitation of vehicle population and usage,and the scrappage of older vehicles is applied,Nanjing and Wuxi will not be able to meet the NOx emissions target by 2020.Therefore,additional control measures are proposed for Nanjing and Wuxi to further mitigate NOx emissions from heavy-duty diesel vehicles.
基金supported by the Key Research and Development Program of Guangdong Province (2020B020222001)the National Natural Science Foundation of China (Grant Nos. 31972659, 31902252, 31672564, 31602053)+5 种基金Guangdong Basic and Applied Basic Research Foundation (2019A1515012006)Natural Science Foundation of Guangdong Province (2018B030315009)China Postdoctoral Science Foundation (2019M652922)the Special Project of National Modern Agricultural Industrial Technology System (CARS-41)the Chief expert Project of Agricultural Industry Technology system in Guangdong Province (2019KJ128)the support of Instrumental Anlysis&Research Center of South China Agriculture University。
文摘Subgroup J avian leukosis virus(ALV-J) is a highly oncogenic retrovirus that has been devastating the global poultry industry since the late 1990s. The major infection model of ALV-J is vertical transmission, which is responsible for the congenital infection of progeny from generation to generation. Increasing evidence has suggested that extracellular vesicles(EVs) derived from virus-infected cells or biological fluids have been thought to be vehicles of transmission for viruses. However, the role of EVs in infection and transmission of ALV-J remains obscure. In the present study, semen extracellular vesicles(SE) were isolated and purified from ALV-J-infected rooster seminal plasma(SE-ALV-J), which was shown to contain ALV-J genomic RNA and partial viral proteins, as determined by RNA sequencing, reverse transcription-quantitative PCR and Western blotting. Furthermore, SE-ALV-J was proved to be able to transmit ALV-J infection to host cells and establish productive infection.More importantly, artificial insemination experiments showed that SE-ALV-J transmitted ALV-J infection to SPF hens, and subsequently mediated vertical transmission of ALV-J from the SPF hens to the progeny chicks. Taken together, the results of the present study suggested that ALV-J utilized host semen extracellular vesicles as a novel means for vertical transmission, enhancing our understanding on mechanisms underlying ALV-J transmission.
基金supported by the Strategic Priority Program of the Chinese Academy of Sciences(Grant No.XDB41000000)the NSFC(Grant Nos 42188101 and 42130204).
文摘Locating the source of decametric(DAM)radio emissions is a key step in the use of remote radio observations to understand the Jovian magnetospheric dynamics and their interaction with the planet’s moons.Wang YM et al.(2020)presented a method by which recorded arc-shaped DAM emissions in the radio dynamic spectra can be used to locate the source of a DAM.An Io-related DAM event on March 14,2014 was used to demonstrate the method.A key parameter in the method is whether the DAM is emitted in the northern or the southern hemisphere;the hemisphere of origin can be determined definitively from the polarization of the emission.Unfortunately,polarization information for the emission on March 14,2014 event was not recorded.Our analysis assumed the source to be in the northern hemisphere.Lamy et al.(2022)argue convincingly that the source was probably in the southern hemisphere.We appreciate the helpful contribution of Lamy et al.(2022)to this discussion and have updated our analysis,this time assuming that the DAM source was in the southern hemisphere.We also explore the sensitivity of our method to another parameter-the height at which the value of fce,max,which is the maximal electron cyclotron frequency reached along the active magnetic flux tube,is adopted.Finally,we introduce our recent statistical study of 68 DAM events,which lays a more solid basis for testing the reliability of our method,which we continue to suggest is a promising tool by which remote radio observations can be used to locate the emission source of Jovian DAMs.
基金support by the Strategic Priority Program of the Chinese Academy of Sciences (Grant Nos. XDB41000000, XDA15017300)the NSFC (Grant No.41842037 and 41574167)support by an appointment to the NASA postdoctoral program at the NASA Goddard Space Flight Center administered by Universities Space Research Association under contract with NASA and the Czech Science Foundation grant 1706818Y
文摘Decametric(DAM) radio emissions are one of the main windows through which one can reveal and understand the Jovian magnetospheric dynamics and its interaction with the moons. DAMs are generated by energetic electrons through cyclotron-maser instability. For Io(the most active moon) related DAMs, the energetic electrons are sourced from Io volcanic activities, and quickly trapped by neighboring Jovian magnetic field. To properly interpret the physical processes behind DAMs, it is important to precisely locate the source field lines from which DAMs are emitted. Following the work by Hess et al.(2008, 2010), we develop a method to locate the source region as well as the associated field lines for any given DAM emission recorded in a radio dynamic spectrum by, e.g.,Wind/WAVES or STEREO/WAVES. The field lines are calculated by the state-of-art analytical model, called JRM09(Connerney et al., 2018).By using this method, we may also derive the emission cone angle and the energy of associated electrons. If multiple radio instruments at different perspectives observe the same DAM event, the evolution of its source region and associated field lines is able to be revealed. We apply the method to an Io-DAM event, and find that the method is valid and reliable. Some physical processes behind the DAM event are also discussed.
文摘BACKGROUND The prevalence of Crohn’s disease(CD)and ulcerative colitis(UC)is on the rise worldwide.This rising prevalence is concerning as patients with CD and UC may frequently relapse leading to recurrent hospitalizations and increased healthcare utilization.AIM To identify trends and adverse outcomes for 30 d readmissions for CD and UC.METHODS This was a retrospective,interrupted trends study involving all adult(≥18 years)30 d readmissions of CD and UC from the National Readmission Database(NRD)between 2008 and 2018.Patients<18 years,elective,and traumatic hospitalizations were excluded from this study.We identified hospitalization characteristics and readmission rates for each calendar year.Trends of inpatient mortality,mean length of hospital stay(LOS)and mean total hospital cost(THC)were calculated using a multivariate logistic trend analysis adjusting for age,gender,insurance status,comorbidity burden and hospital factors.Furthermore,trends between CD and UC readmissions were compared using regression of the interaction coefficient after adjusting for age and gender to determine relative trends between the two populations.Stata®Version 16 software(StataCorp,TX,United States)was used for statistical analysis and P value≤0.05 were considered statistically significant.RESULTS Total number of 30 d readmissions increased from 6202 in 2010 to 7672 in 2018 for CD and from 3272 in 2010 to 4234 in 2018 for UC.We noted increasing trends for 30-day all-cause readmission rate of CD from 14.9%in 2010 to 17.6%in 2018(P-trend<0.001),CD specific readmission rate from 7.1%in 2010 to 8.2%in 2018(P-trend<0.001),30-day all-cause readmission rate of UC from 14.1%in 2010 to 15.7%in 2018(P-trend=0.003),and UC specific readmission rate from 5.2%in 2010 to 5.6%in 2018(P-trend=0.029).There was no change in the risk adjusted trends of inpatient mortality and mean LOS for CD and UC readmissions.However,we found an increasing trend of mean THC for UC readmissions.After comparison,there was no statistical difference in the trends for 30 d all-cause readmission rate,inpatient mortality,and mean LOS between CD and UC readmissions.CONCLUSION There was an increase in total number of 30 d readmissions for CD and UC with a trend towards increasing 30 d all-cause readmission rates.
文摘Background: The Implantable Cardiac Monitor (ICM) is an invaluable tool for detecting cardiac arrhythmias by providing physicians. Critical to the success of ICMs depends on how quickly and accurately the data can be transmitted to a physician’s office after an arrhythmic event. Then, the clinical event can be analyzed and the treatment will be provided accordingly. However, no reports have been published as to how efficiently the ICM data is transmitted. Methods: There is a retrospective review of 520 patients who received a Medtronic Reveal LINQTM between 2/01/2015 and 6/01/2017. The time from the arrhythmic event to the time of physician notification was calculated and reason for delay was noted. Results: One hundred and twenty patients out of 520 patients (23%) had arrhythmic events transmitted over a mean follow up of 14 ± 4 months. The mean time between cardiac events and physician notification was 15 ± 8 days. Sixty-three percent (63%) of data transmission delay (defined as >24 hours) was due to the MyCareLinkTM Monitor not being in proximity to the patient. Connection failure between the monitor and the network accounted for 34% of data transmission delay. Conclusion: Significant delay in data transmission from Medtronic Reveal LINQTM cardiac monitor occurs frequently impacting patient care. Newer generations of the implantable cardiac monitors utilize Bluetooth technology, enabling immediate transfer of data from ICM to a patient’s cellular phone and subsequently to their physician’s office. This technology could potentially improve efficiency and reliability eliminating the issues of proximity and connectivity.
文摘BACKGROUND Alcoholic liver cirrhosis(ALC)is a chronic liver disease with varying disease severity.Readmissions of ALC are associated with poor outcomes.AIM To identify and assess trends of readmissions for ALC over an eight-year period.METHODS This retrospective interrupted trend study analysed 30-d readmissions of ALC in the United States from 2010 to 2018 using the National Readmissions Database.Hospitalization for ALC was the reason for index admission obtained using the International Classification of Diseases codes(571.2 and K70.3X).Biodemographic characteristics and hospitalization trends were highlighted over time.A multivariate regression analysis model was used to calculate the trend for riskadjusted odds of 30-d all-cause ALC readmissions,ALC specific readmission rate,ALC readmission proportion,inpatient mortality,mean length of stay(LOS)and mean total hospital cost(THC)following adjustments for age,gender,grouped Charlson Comorbidity Index,insurance,mean household income,and hospital characteristics.RESULTS There was a trend towards increasing total 30-d readmissions of ALC from 7660 in 2010 to 15085 in 2018(P<0.001).Patients readmitted for ALC were noted to have an increasing comorbidity burden over time.We noted a rise in the risk-adjusted 30-d all-cause readmission of ALC from 24.9%in 2010 to 29.9%in 2018(P<0.001).ALC-specific readmission rate increased from 6.3%in 2010 to 8.4%in 2018(P<0.001)while ALC readmission proportion increased from 31.4%in 2010 to 36.3%in 2018(P<0.001).Inpatient mortality for 30-d readmissions of ALC declined from 10.5%in 2010 to 8.2%in 2018(P=0.0079).However,there was a trend towards increasing LOS from 5.6 d in 2010 to 6.3 d in 2018(P<0.001)and increasing THC from 13790 dollars in 2010 to 17150 dollars in 2018(P<0.001).The total days of hospital stay attributable to 30-d readmissions of ALC increased by 119.2%while the total attributable hospital costs increased by 149%by the end of 2018.CONCLUSION There was an increase in the 30-d readmission rate and comorbidity burden for ALC;however,inpatient mortality declined.Additionally,there was a trend towards increasing LOS and THC for these readmissions.
文摘Background: Despite efforts to expand prevention of mother-to-child transmission (PMTCT) of HIV in resource-limited settings, only 53% of women in sub-Saharan Africa receive adequate PMTCT services. Understanding factors that enable successful program completion are crucial to improving adherence rates to PMTCT programs in these settings. Using a positive deviance approach, we explored patient and provider’s perspectives on factors enabling women to successfully access and adhere to PMTCT services to identify areas of program improvement and further reduce HIV transmission. Methods: Semi-structured interviews were conducted with 11 health care workers (HCWs) at two health centers in Kara, Togo and 34 women who had successfully completed the PMTCT program at those facilities. Women were identified using purposive sampling and content theme analysis was used to analyze the data. Results: Knowledge and belief in the potential to give birth to an HIV-negative child, supported by facilitating factors on the individual and community levels, was the cornerstone to women’s PMTCT program success. Effective program education and peer-to-peer interactions fostered the participants’ knowledge and belief in PMTCT, with the resulting internal motivation driving continued participation and adherence. The welcoming environment, availability of peer support groups and financial assistance from the health facility, further facilitated success, with women using this facility-based community to seek advice and support from HCWs and peers. Financial, physical, and emotional support from relatives was also important in ensuring unhindered access. Finally, the faith-based communities’ acceptance and support for HIV-positive women further encouraged participants to adhere to the program. Conclusion: Understanding and believing in the ability to have an HIV-negative baby was the most important facilitator for PMTCT program adherence. This led to internal motivation that was continually reinforced through facility and community supportive environments focused on addressing barriers. Efforts to improve PMTCT success should focus on all of these factors through a patient-centered approach.
基金supported by Korea Institute for Advancement of Technology(KIAT)grant funded by the Korea Government(MOTIE)(P0012724,The Competency Development Program for Industry Specialist)and the Soonchunhyang University Research Fund.
文摘Wireless sensor networks(WSNs)are projected to have a wide range of applications in the future.The fundamental problem with WSN is that it has afinite lifespan.Clustering a network is a common strategy for increasing the life-time of WSNs and,as a result,allowing for faster data transmission.The cluster-ing algorithm’s goal is to select the best cluster head(CH).In the existing system,Hybrid grey wolf sunflower optimization algorithm(HGWSFO)and optimal clus-ter head selection method is used.It does not provide better competence and out-put in the network.Therefore,the proposed Hybrid Grey Wolf Ant Colony Optimisation(HGWACO)algorithm is used for reducing the energy utilization and enhances the lifespan of the network.Black hole method is used for selecting the cluster heads(CHs).The ant colony optimization(ACO)technique is used tofind the route among origin CH and destination.The open cache of nodes,trans-mission power,and proximity are used to improve the CH selection.The grey wolf optimisation(GWO)technique is the most recent and well-known optimiser module which deals with grey wolves’hunting activity(GWs).These GWs have the ability to track down and encircle food.The GWO method was inspired by this hunting habit.The proposed HGWACO improves the duration of the net-work,minimizes the power consumption,also it works with the large-scale net-works.The HGWACO method achieves 25.64%of residual energy,25.64%of alive nodes,40.65%of dead nodes also it enhances the lifetime of the network.
