Mostly based on assumptions derived from controlled-environment studies, predicted future atmospheric CO2 concentrations [CO2] are expected to have considerable impacts on carbon （C） turnover in agro-ecosystems. In ...Mostly based on assumptions derived from controlled-environment studies, predicted future atmospheric CO2 concentrations [CO2] are expected to have considerable impacts on carbon （C） turnover in agro-ecosystems. In order to allow the in situ examination of C-transformations in the plant-soil system of arable crop rotations under future [002], a free air carbon dioxide enrichment （FACE） experiment （550 μmol mol^-1 CO2） was started at Braunschweig, Germany in 1999. The crop rotation under investigation comprised winter barley, a cover crop （ryegrass）, sugar beets and winter wheat. Assessments of CO2 effects included the determination of above- and belowground biomass production, measurements of canopy CO2- and H2O- fluxes, soil microbial biomass and in situ soil respiration. The results obtained during the 1st crop rotation cycle （3 years） showed that for the selected crops elevated [CO2] entailed significant positive effects （P 〈 0.05） on aboveground （6%-14% stimulation） and belowground biomass production （up to 90% stimulation）, while canopy evapotranspiration was reduced. This resulted in increased soil water content. Also, depending on crop type and season, high CO2 stimulated in situ soil respiration （up to 30%）, while soil microbial biomass did not show significant respouses to elevated [CO2] during the first rotation cycle.展开更多
Background: Non-implantable bone anchored hearing devices (BCHDs) are utilized for patients with conductive or mixed hearing loss who are unsuitable for conventional hearing aids or have unresolved middle ear issues. ...Background: Non-implantable bone anchored hearing devices (BCHDs) are utilized for patients with conductive or mixed hearing loss who are unsuitable for conventional hearing aids or have unresolved middle ear issues. These devices can be surgically implanted or attached using adhesive plates, dental sticks, elastic headbands, or bone conduction spectacles. Optimal fitting of bone conduction spectacles requires appropriate frame selection and contact pressure in the temporal and mastoid areas. The ANSI S3.6 and DIN EN ISO 389-3 standards recommend a contact area of approximately 1.75 cm2 and a maximum force of 5.4 N for effective sound transmission and comfort. Methods: This study aimed to evaluate the technical fit and mechanical stability of universal bone conduction hearing spectacles compared to established systems. A Sen-Pressure 02 thin-film sensor connected to an Arduino Uno R3 board measured contact force in the temporal and mastoid areas. Several BCHDs were tested, including the Bruckhoff la belle BC D50/70, Radioear B71 headset, Radioear B71 elastic headband, Cochlear Baha SoundArc M, and Cochlear Baha elastic headband, on a PVC artificial head, with data analyzed using ANOVA and LSD post hoc tests. Results: The la belle BC D50/70 spectacles showed comparable contact force to established BCHDs, ensuring adequate sound transmission and comfort. Significant differences were observed between the systems, with the Radioear B71 headset exhibiting the highest forces. The la belle BC D50/70 had similar forces to the Radioear B71 elastic headband. Conclusion: The la belle BC D50/70 universal bone conduction hearing spectacles are a technically equivalent alternative to established BCHDs, maintaining pressure below 5.4 N. Future research should explore the impact of different contact forces on performance and comfort, and the integration of force control in modified spectacles. This study indicates that the la belle BC D50/70 is a viable alternative that meets audiological practice requirements.展开更多
The arc furnace technology is an ideally suited process for the treatment of hazardous and problematic waste. The operation conditions of the furnace can be adapted for optimal transformation of the waste material inp...The arc furnace technology is an ideally suited process for the treatment of hazardous and problematic waste. The operation conditions of the furnace can be adapted for optimal transformation of the waste material input into raw materials and usable products. The process can significantly reduce the impact of contaminated wastes and industrial residues, and enable material conversion and separation. Thus, the products of the process have various applications. The capability of the process is illustrated with three examples, the treatment of bottom ash and filter ash from waste incineration plants, of stainless steel slags and of chromium-containing residues from the refractory industry.展开更多
<strong>Background:</strong> Clinical judgment is a specific role that establishes a professional identity. The purpose of this paper is to prepare nursing students to make better judgments in the clinical...<strong>Background:</strong> Clinical judgment is a specific role that establishes a professional identity. The purpose of this paper is to prepare nursing students to make better judgments in the clinical setting and realign learning and teaching. <strong>Methods: </strong>We used six steps to arrive at a competent clinical judgment suggested by the National Council State Board of Nursing (NSCBN) as a clinical judgment model 1) recognizing cues, 2) analyzing cues, 3) prioritizing hypotheses, 4) generating solutions, 5) taking an action, and 6) evaluating outcomes during the head-to-toe examination of the patient. <strong>Results: </strong>The primary outcomes are stabilization of the hemodynamics of the patient and prevention of further blood loss. Fluids are being given to help keep the vascular volume from being depleted, but they cannot solve the underlying problem. Continued assessment, intervention, and monitoring of vital signs through the course of the hospital stay ending with the patient’s discharge. <strong>Discussion:</strong> Survivors of sexual assault are unique for a nurse to provide care. The nurse needs to assess, intervene, monitor, and pay attention to detail of the 6 steps to clinical judgment, resulting in positive outcomes for their patient. <strong>Conclusions:</strong> Forensic nursing is a field of nursing that focuses on sexual assault survivor care and works to make the aftermath of their tragic situation easier to cope with. Strengthening clinical judgment skills could remedy significant mistakes made by novice forensic nurses. Critical thinking and clinical ethical reasoning are the building blocks of clinical judgment.展开更多
Non-ribosomal peptide synthetases(NRPSs)are attractive targets for biosynthetic pathway engineering due to their modular architecture and the therapeutic relevance of their products.With catalysis mediated by specific...Non-ribosomal peptide synthetases(NRPSs)are attractive targets for biosynthetic pathway engineering due to their modular architecture and the therapeutic relevance of their products.With catalysis mediated by specific protein-protein interactions formed between the peptidyl carrier protein(PCP)and its partner enzymes,NRPS enzymology and control remains fertile ground for discovery.This review focuses on the recent efforts within structural biology by compiling high-resolution structural data that shed light into the various protein-protein interfaces formed between the PCP and its partner enzymes,including the phosphopantetheinyl transferase(PPTase),adenylation(A)domain,condensation(C)domain,thioesterase(TE)domain and other tailoring enzymes within the synthetase.Integrating our understanding of how the PCP recognizes partner proteins with the potential to use directed evolution and combinatorial biosynthetic methods will enhance future efforts in discovery and production of new bioactive compounds.展开更多
Aims Factors limiting distributions of species are fundamental to ecology and evolution but have rarely been addressed experimentally for multiple species.The conspicuous linear distribution patterns of plant species ...Aims Factors limiting distributions of species are fundamental to ecology and evolution but have rarely been addressed experimentally for multiple species.The conspicuous linear distribution patterns of plant species confined to river corridors in the Central European lowlands constitute an especially long-standing distribution puzzle.We experimentally tested our novel hypothesis that the tolerance of species to river corridor conditions is independent of the degree of confinement to river corridor habitats,but that species not confined to river corridors are better able to take advantage of the more benign non-river corridor conditions.Methods We grew 42 herbaceous species differing in their confinement to river corridors in a common garden experiment on loamy soil typical for river corridor areas and sandy soil typical for non-river corridor areas,and with and without a flooding period.For a subset of species,we grew plants of both river corridor and non-river corridor origin to test for adaptation to river corridor conditions.Important findings Species more confined to river corridor areas benefited less from the more benign non-flooded and non-river corridor soil conditions than species of wider distributional range did.For subsets of 7 and 12 widespread species,the response to flooding and soil origin,respectively,did not differ between plants from river corridor sites and plants from other sites,suggesting that the habitat tolerance of widespread species is due to phenotypic plasticity rather than to local adaptation.Overall,we found clear support for our novel hypothesis that species not confined to river corridors are more able to take advantage of the more benign non-river corridor conditions.Our study provides a general hypothesis on differences between species confined to stressful habitats and widespread species out for test in further multispecies comparative experiments.展开更多
Objective:This study was conducted to determine whether there is a reliable method for measuring the thickness of the retroauricular skin before,during,and after cochlear implantation,which allows the assessment of th...Objective:This study was conducted to determine whether there is a reliable method for measuring the thickness of the retroauricular skin before,during,and after cochlear implantation,which allows the assessment of the optimal force of the external magnet of the cochlear implant(CI).Methods:The retroauricular skin thickness of 83 patients who received a CI was measured using three different methods.The thickness was measured on pre-and postoperative CT images,as well as intraoperatively.The magnet category chosen by the surgeon was recorded when the implant was switched on and during the first follow-up visit.Correlation analyses were performed on the different skin thickness measurements and between the skin thickness and magnet strength categories.Results:Only six patients required an exchange of the magnet until the follow-up.Although the median absolute thickness differed significantly between the three measures(p<0.0001),their thickness values showed highly significant correlations(Pearson’s r=0.457-0.585;p<0.01).In addition,magnet strength,was significantly correlated with the flap thickness determined pre-,post-,and during surgery.The lowest correlation with magnet strength was found in the intraoperative needle method.Conclusion:All three measurements methods provided a suitable base for determining the ideal magnetic force.However,of particular interest were the pre-and postoperative CT measurements.The first enabled the early assessment of the required magnetic strength and thus a timely postoperative supply,whereas the latter helped to estimate the need for magnetic strength reduction during follow-up care and the feasibility of an early swith-on.展开更多
Permanent pacemaker implant is a commonly performed cardiac procedure for treatment of bradycardia or conduction system abnormality.With conventional right ventricular(RV)pacing a lead is implanted at the RV apex or o...Permanent pacemaker implant is a commonly performed cardiac procedure for treatment of bradycardia or conduction system abnormality.With conventional right ventricular(RV)pacing a lead is implanted at the RV apex or on the RV septum.However,RV apical or RV septal pacing causes iatrogenic left bundle-branch block and ventricular dyssynchrony and can lead to adverse cardiac remodeling,a pacing-mediated cardiomyopathy,and congestive heart failure.Alternatively,permanent His-bundle pacing uses the intrinsic rapidly-conducting His-Purkinje system to activate the ventricle,thereby maintaining(or sometimes even restoring)ventricular synchrony.Many patients may derive benefit from permanent His-bundle pacing.展开更多
This paper reviews current recommendations on the appropriate evaluation and management of cardiac arrhythmias in the pregnant patient.Most arrhythmias during pregnancy are benign and require no intervention.When requ...This paper reviews current recommendations on the appropriate evaluation and management of cardiac arrhythmias in the pregnant patient.Most arrhythmias during pregnancy are benign and require no intervention.When required,the decision to treat should be based on symptom severity and the associated risk to mother and fetus posed by potentially recurring arrhythmia episodes throughout the pregnancy.Any treatment strategy in this patient population has inherent risk to both mother and unborn child.Before the initiation of any intervention,documentation of a clinical arrhythmia and correlation with clinical symptoms should be obtained.There is no role for empiric therapy.展开更多
This paper will develop a Li-Yau-Hamilton type differential Harnack estimate for positive solutions to the Newell-Whitehead-Segel equation on R^n.We then use our LYH-differential Harnack inequality to prove several pr...This paper will develop a Li-Yau-Hamilton type differential Harnack estimate for positive solutions to the Newell-Whitehead-Segel equation on R^n.We then use our LYH-differential Harnack inequality to prove several properties about positive solutions to the equation,including deriving a classical Harnack inequality and characterizing standing solutions and traveling wave solutions.展开更多
High catalytic activity and substrate specificity make enzymes a rich source of inspiration for catalyst development.Co-opting the advantages of natural materials while tuning them to a modified form and purpose,howev...High catalytic activity and substrate specificity make enzymes a rich source of inspiration for catalyst development.Co-opting the advantages of natural materials while tuning them to a modified form and purpose,however,is not a straightforward synthetic task.Polymerization of L-3,4-dihydroxyphenylalanine(L-DOPA)results in amorphous polymer nanoparticles that are similar in many ways to natural eumelanin.Herein,the authors introduce mesoporosity and iron ion chelation to synthesize a variant of the L-DOPA polymer with high peroxidase-like activity.Our results indicate catalytic reaction with peroxide under mildly acidic conditions(pH 5.4 and 6)with a greater maximum reaction velocity(Vmax)than horseradish peroxidase(HRP)at optimal pH 3.5–4.5.Comparison between Fe(Ⅲ)and Fe(Ⅱ)loading indicates that either can be used as a starting point to trigger reactivity,though Fe(Ⅱ)loading leads to materials with twice the Vmax of the Fe(Ⅲ)-loaded sample.The lack of catalyst degradation despite the redox changes and presence of radical species is consistent with the robust nature and redox versatility of polydopamine-based materials and demonstrates strong potential as a versatile redox-catalysis platform.展开更多
Background:Implantable cardioverter-defi brillators(ICDs)can be life-saving devices,although they are expensive and may cause complications.In 2013,several professional societies published joint appropriate use criter...Background:Implantable cardioverter-defi brillators(ICDs)can be life-saving devices,although they are expensive and may cause complications.In 2013,several professional societies published joint appropriate use criteria(AUC)assessing indications for ICD implantation.Data evaluating the clinical application of AUC are limited.Previous registry-based studies estimated that 22.5%of primary prevention ICD implantations were“non-evidence-based”implantations.On the basis of AUC,we aimed to determine the prevalence of“rarely appropriate”ICD implantation at our institution for comparison with previous estimates.Methods:We reviewed 286 patients who underwent ICD implantation between 2013 and 2016.Appropriateness of each ICD implantation was assessed by independent review and rated on the basis of AUC.Results:Of 286 ICD implantations,two independent reviewers found that 89.5%and 89.2%,respectively,were appropriate,5.6%and 7.3%may be appropriate,and 1.8%and 2.1%were rarely appropriate.No AUC indication was found for 3.5%and 3.4%of ICD implantations,respectively.Secondary prevention ICD implantations were more likely rarely appropriate(2.6%vs.1.2%and 3.6%vs.1.1%)or unrated(6.0%vs.1.2%and 2.7%vs.0.6%).The reviewers found 3.5%and 3.4%of ICD implantations,respectively,were non-evidence-based implantations.The difference in rates between reviewers was not statistically signifi cant.Conclusion:Compared with prior reports,our prevalence of rarely appropriate ICD implantation was very low.The high appropriate use rate could be explained by the fact that AUC are based on current clinical practice.The AUC could benefi t from additional secondary prevention indications.Most importantly,clinical judgement and individualized care should determine which patients receive ICDs irrespective of guidelines or criteria.展开更多
Background: Cochlear implants (CI) are widely used to restore hearing in people with severe to profound hearing loss. However, optimizing CI performance, especially in difficult listening environments with background ...Background: Cochlear implants (CI) are widely used to restore hearing in people with severe to profound hearing loss. However, optimizing CI performance, especially in difficult listening environments with background noise, remains a major challenge. Understanding the influence of factors such as sound source position and electrode placement on CI stimulation patterns is critical to improving auditory perception. Methods: In this study, an analysis was conducted to investigate the influence of sound source position and electrode placement on CI stimulation patterns under noisy conditions. For this purpose, a special measurement setup with a CI speech processor-microphone test box was used to simulate realistic listening scenarios and measure CI performance. Results: The results show that the effectiveness of CI noise reduction systems is influenced by factors such as the position of the sound source and electrode placement. In particular, the beamforming ultra zoom mode showed significantly better noise reduction than the omnidirectional mode, especially under real listening conditions. Furthermore, differences in electrode responses indicate individual variability in the CI user experience, highlighting the importance of personalized fitting algorithms. Conclusions: The results demonstrate the importance of considering environmental factors and individual differences when optimizing CI performance. Future research efforts should focus on the development of personalized fitting algorithms and the exploration of innovative strategies, such as the integration of artificial intelligence, to improve CI functionality in different listening environments. This study contributes to our understanding of CI stimulation patterns and lays the foundation for improving auditory perception in CI users.展开更多
基金Project supported by the German Ministry of Consumer Protection, Food and Agriculture (BMVEL) and the German Science Foundation (DFG) (No.WE 1839/1-1)
文摘Mostly based on assumptions derived from controlled-environment studies, predicted future atmospheric CO2 concentrations [CO2] are expected to have considerable impacts on carbon （C） turnover in agro-ecosystems. In order to allow the in situ examination of C-transformations in the plant-soil system of arable crop rotations under future [002], a free air carbon dioxide enrichment （FACE） experiment （550 μmol mol^-1 CO2） was started at Braunschweig, Germany in 1999. The crop rotation under investigation comprised winter barley, a cover crop （ryegrass）, sugar beets and winter wheat. Assessments of CO2 effects included the determination of above- and belowground biomass production, measurements of canopy CO2- and H2O- fluxes, soil microbial biomass and in situ soil respiration. The results obtained during the 1st crop rotation cycle （3 years） showed that for the selected crops elevated [CO2] entailed significant positive effects （P 〈 0.05） on aboveground （6%-14% stimulation） and belowground biomass production （up to 90% stimulation）, while canopy evapotranspiration was reduced. This resulted in increased soil water content. Also, depending on crop type and season, high CO2 stimulated in situ soil respiration （up to 30%）, while soil microbial biomass did not show significant respouses to elevated [CO2] during the first rotation cycle.
文摘Background: Non-implantable bone anchored hearing devices (BCHDs) are utilized for patients with conductive or mixed hearing loss who are unsuitable for conventional hearing aids or have unresolved middle ear issues. These devices can be surgically implanted or attached using adhesive plates, dental sticks, elastic headbands, or bone conduction spectacles. Optimal fitting of bone conduction spectacles requires appropriate frame selection and contact pressure in the temporal and mastoid areas. The ANSI S3.6 and DIN EN ISO 389-3 standards recommend a contact area of approximately 1.75 cm2 and a maximum force of 5.4 N for effective sound transmission and comfort. Methods: This study aimed to evaluate the technical fit and mechanical stability of universal bone conduction hearing spectacles compared to established systems. A Sen-Pressure 02 thin-film sensor connected to an Arduino Uno R3 board measured contact force in the temporal and mastoid areas. Several BCHDs were tested, including the Bruckhoff la belle BC D50/70, Radioear B71 headset, Radioear B71 elastic headband, Cochlear Baha SoundArc M, and Cochlear Baha elastic headband, on a PVC artificial head, with data analyzed using ANOVA and LSD post hoc tests. Results: The la belle BC D50/70 spectacles showed comparable contact force to established BCHDs, ensuring adequate sound transmission and comfort. Significant differences were observed between the systems, with the Radioear B71 headset exhibiting the highest forces. The la belle BC D50/70 had similar forces to the Radioear B71 elastic headband. Conclusion: The la belle BC D50/70 universal bone conduction hearing spectacles are a technically equivalent alternative to established BCHDs, maintaining pressure below 5.4 N. Future research should explore the impact of different contact forces on performance and comfort, and the integration of force control in modified spectacles. This study indicates that the la belle BC D50/70 is a viable alternative that meets audiological practice requirements.
基金Part of the work was supported by the EU LIFE Program (LIFE03ENV/D/043-Recarc)
文摘The arc furnace technology is an ideally suited process for the treatment of hazardous and problematic waste. The operation conditions of the furnace can be adapted for optimal transformation of the waste material input into raw materials and usable products. The process can significantly reduce the impact of contaminated wastes and industrial residues, and enable material conversion and separation. Thus, the products of the process have various applications. The capability of the process is illustrated with three examples, the treatment of bottom ash and filter ash from waste incineration plants, of stainless steel slags and of chromium-containing residues from the refractory industry.
文摘<strong>Background:</strong> Clinical judgment is a specific role that establishes a professional identity. The purpose of this paper is to prepare nursing students to make better judgments in the clinical setting and realign learning and teaching. <strong>Methods: </strong>We used six steps to arrive at a competent clinical judgment suggested by the National Council State Board of Nursing (NSCBN) as a clinical judgment model 1) recognizing cues, 2) analyzing cues, 3) prioritizing hypotheses, 4) generating solutions, 5) taking an action, and 6) evaluating outcomes during the head-to-toe examination of the patient. <strong>Results: </strong>The primary outcomes are stabilization of the hemodynamics of the patient and prevention of further blood loss. Fluids are being given to help keep the vascular volume from being depleted, but they cannot solve the underlying problem. Continued assessment, intervention, and monitoring of vital signs through the course of the hospital stay ending with the patient’s discharge. <strong>Discussion:</strong> Survivors of sexual assault are unique for a nurse to provide care. The nurse needs to assess, intervene, monitor, and pay attention to detail of the 6 steps to clinical judgment, resulting in positive outcomes for their patient. <strong>Conclusions:</strong> Forensic nursing is a field of nursing that focuses on sexual assault survivor care and works to make the aftermath of their tragic situation easier to cope with. Strengthening clinical judgment skills could remedy significant mistakes made by novice forensic nurses. Critical thinking and clinical ethical reasoning are the building blocks of clinical judgment.
基金J.C.C.was supported by the National Institute of General Medical Science(NIGMS)of the National Institutes of Health(NIH)under award number 1F31GM13761601A1J.O.S.was supported by the ACS Bridge Program and The Genentech FoundationThis work was supported by the NIGMS of the NIH under award number R01GM095970.
文摘Non-ribosomal peptide synthetases(NRPSs)are attractive targets for biosynthetic pathway engineering due to their modular architecture and the therapeutic relevance of their products.With catalysis mediated by specific protein-protein interactions formed between the peptidyl carrier protein(PCP)and its partner enzymes,NRPS enzymology and control remains fertile ground for discovery.This review focuses on the recent efforts within structural biology by compiling high-resolution structural data that shed light into the various protein-protein interfaces formed between the PCP and its partner enzymes,including the phosphopantetheinyl transferase(PPTase),adenylation(A)domain,condensation(C)domain,thioesterase(TE)domain and other tailoring enzymes within the synthetase.Integrating our understanding of how the PCP recognizes partner proteins with the potential to use directed evolution and combinatorial biosynthetic methods will enhance future efforts in discovery and production of new bioactive compounds.
文摘Aims Factors limiting distributions of species are fundamental to ecology and evolution but have rarely been addressed experimentally for multiple species.The conspicuous linear distribution patterns of plant species confined to river corridors in the Central European lowlands constitute an especially long-standing distribution puzzle.We experimentally tested our novel hypothesis that the tolerance of species to river corridor conditions is independent of the degree of confinement to river corridor habitats,but that species not confined to river corridors are better able to take advantage of the more benign non-river corridor conditions.Methods We grew 42 herbaceous species differing in their confinement to river corridors in a common garden experiment on loamy soil typical for river corridor areas and sandy soil typical for non-river corridor areas,and with and without a flooding period.For a subset of species,we grew plants of both river corridor and non-river corridor origin to test for adaptation to river corridor conditions.Important findings Species more confined to river corridor areas benefited less from the more benign non-flooded and non-river corridor soil conditions than species of wider distributional range did.For subsets of 7 and 12 widespread species,the response to flooding and soil origin,respectively,did not differ between plants from river corridor sites and plants from other sites,suggesting that the habitat tolerance of widespread species is due to phenotypic plasticity rather than to local adaptation.Overall,we found clear support for our novel hypothesis that species not confined to river corridors are more able to take advantage of the more benign non-river corridor conditions.Our study provides a general hypothesis on differences between species confined to stressful habitats and widespread species out for test in further multispecies comparative experiments.
文摘Objective:This study was conducted to determine whether there is a reliable method for measuring the thickness of the retroauricular skin before,during,and after cochlear implantation,which allows the assessment of the optimal force of the external magnet of the cochlear implant(CI).Methods:The retroauricular skin thickness of 83 patients who received a CI was measured using three different methods.The thickness was measured on pre-and postoperative CT images,as well as intraoperatively.The magnet category chosen by the surgeon was recorded when the implant was switched on and during the first follow-up visit.Correlation analyses were performed on the different skin thickness measurements and between the skin thickness and magnet strength categories.Results:Only six patients required an exchange of the magnet until the follow-up.Although the median absolute thickness differed significantly between the three measures(p<0.0001),their thickness values showed highly significant correlations(Pearson’s r=0.457-0.585;p<0.01).In addition,magnet strength,was significantly correlated with the flap thickness determined pre-,post-,and during surgery.The lowest correlation with magnet strength was found in the intraoperative needle method.Conclusion:All three measurements methods provided a suitable base for determining the ideal magnetic force.However,of particular interest were the pre-and postoperative CT measurements.The first enabled the early assessment of the required magnetic strength and thus a timely postoperative supply,whereas the latter helped to estimate the need for magnetic strength reduction during follow-up care and the feasibility of an early swith-on.
文摘Permanent pacemaker implant is a commonly performed cardiac procedure for treatment of bradycardia or conduction system abnormality.With conventional right ventricular(RV)pacing a lead is implanted at the RV apex or on the RV septum.However,RV apical or RV septal pacing causes iatrogenic left bundle-branch block and ventricular dyssynchrony and can lead to adverse cardiac remodeling,a pacing-mediated cardiomyopathy,and congestive heart failure.Alternatively,permanent His-bundle pacing uses the intrinsic rapidly-conducting His-Purkinje system to activate the ventricle,thereby maintaining(or sometimes even restoring)ventricular synchrony.Many patients may derive benefit from permanent His-bundle pacing.
文摘This paper reviews current recommendations on the appropriate evaluation and management of cardiac arrhythmias in the pregnant patient.Most arrhythmias during pregnancy are benign and require no intervention.When required,the decision to treat should be based on symptom severity and the associated risk to mother and fetus posed by potentially recurring arrhythmia episodes throughout the pregnancy.Any treatment strategy in this patient population has inherent risk to both mother and unborn child.Before the initiation of any intervention,documentation of a clinical arrhythmia and correlation with clinical symptoms should be obtained.There is no role for empiric therapy.
基金supported by NSF through the Research Experience for Undergraduates Program at Cornell University, grant-1156350supported by Cornell University Summer Program for Undergraduate Researchpartially supported by a grant from the Simons Foundation (#280161)
文摘This paper will develop a Li-Yau-Hamilton type differential Harnack estimate for positive solutions to the Newell-Whitehead-Segel equation on R^n.We then use our LYH-differential Harnack inequality to prove several properties about positive solutions to the equation,including deriving a classical Harnack inequality and characterizing standing solutions and traveling wave solutions.
基金support from the Air Force of Scientific Research MURI(grant no.FA9550-18-1-0142)supported by the National Science Foundation(grant no.ECCS-1542148)M.K.is supported by the Department of Defense(DoD)through the National Defense Science and Engineering Graduate(NDSEG)Fellowship Program.
文摘High catalytic activity and substrate specificity make enzymes a rich source of inspiration for catalyst development.Co-opting the advantages of natural materials while tuning them to a modified form and purpose,however,is not a straightforward synthetic task.Polymerization of L-3,4-dihydroxyphenylalanine(L-DOPA)results in amorphous polymer nanoparticles that are similar in many ways to natural eumelanin.Herein,the authors introduce mesoporosity and iron ion chelation to synthesize a variant of the L-DOPA polymer with high peroxidase-like activity.Our results indicate catalytic reaction with peroxide under mildly acidic conditions(pH 5.4 and 6)with a greater maximum reaction velocity(Vmax)than horseradish peroxidase(HRP)at optimal pH 3.5–4.5.Comparison between Fe(Ⅲ)and Fe(Ⅱ)loading indicates that either can be used as a starting point to trigger reactivity,though Fe(Ⅱ)loading leads to materials with twice the Vmax of the Fe(Ⅲ)-loaded sample.The lack of catalyst degradation despite the redox changes and presence of radical species is consistent with the robust nature and redox versatility of polydopamine-based materials and demonstrates strong potential as a versatile redox-catalysis platform.
文摘Background:Implantable cardioverter-defi brillators(ICDs)can be life-saving devices,although they are expensive and may cause complications.In 2013,several professional societies published joint appropriate use criteria(AUC)assessing indications for ICD implantation.Data evaluating the clinical application of AUC are limited.Previous registry-based studies estimated that 22.5%of primary prevention ICD implantations were“non-evidence-based”implantations.On the basis of AUC,we aimed to determine the prevalence of“rarely appropriate”ICD implantation at our institution for comparison with previous estimates.Methods:We reviewed 286 patients who underwent ICD implantation between 2013 and 2016.Appropriateness of each ICD implantation was assessed by independent review and rated on the basis of AUC.Results:Of 286 ICD implantations,two independent reviewers found that 89.5%and 89.2%,respectively,were appropriate,5.6%and 7.3%may be appropriate,and 1.8%and 2.1%were rarely appropriate.No AUC indication was found for 3.5%and 3.4%of ICD implantations,respectively.Secondary prevention ICD implantations were more likely rarely appropriate(2.6%vs.1.2%and 3.6%vs.1.1%)or unrated(6.0%vs.1.2%and 2.7%vs.0.6%).The reviewers found 3.5%and 3.4%of ICD implantations,respectively,were non-evidence-based implantations.The difference in rates between reviewers was not statistically signifi cant.Conclusion:Compared with prior reports,our prevalence of rarely appropriate ICD implantation was very low.The high appropriate use rate could be explained by the fact that AUC are based on current clinical practice.The AUC could benefi t from additional secondary prevention indications.Most importantly,clinical judgement and individualized care should determine which patients receive ICDs irrespective of guidelines or criteria.
文摘Background: Cochlear implants (CI) are widely used to restore hearing in people with severe to profound hearing loss. However, optimizing CI performance, especially in difficult listening environments with background noise, remains a major challenge. Understanding the influence of factors such as sound source position and electrode placement on CI stimulation patterns is critical to improving auditory perception. Methods: In this study, an analysis was conducted to investigate the influence of sound source position and electrode placement on CI stimulation patterns under noisy conditions. For this purpose, a special measurement setup with a CI speech processor-microphone test box was used to simulate realistic listening scenarios and measure CI performance. Results: The results show that the effectiveness of CI noise reduction systems is influenced by factors such as the position of the sound source and electrode placement. In particular, the beamforming ultra zoom mode showed significantly better noise reduction than the omnidirectional mode, especially under real listening conditions. Furthermore, differences in electrode responses indicate individual variability in the CI user experience, highlighting the importance of personalized fitting algorithms. Conclusions: The results demonstrate the importance of considering environmental factors and individual differences when optimizing CI performance. Future research efforts should focus on the development of personalized fitting algorithms and the exploration of innovative strategies, such as the integration of artificial intelligence, to improve CI functionality in different listening environments. This study contributes to our understanding of CI stimulation patterns and lays the foundation for improving auditory perception in CI users.
