In the context of ongoing climate change,rela-tionships between tree growth and climate present uncertain-ties,which limits the predictions of future forest dynamics.Northwest China is a region undergoing notable warm...In the context of ongoing climate change,rela-tionships between tree growth and climate present uncertain-ties,which limits the predictions of future forest dynamics.Northwest China is a region undergoing notable warming and increased precipitation;how forests in this region will respond to climate change has not been fully understood.We used dendrochronological methods to examine the rela-tionship between climate and the radial growth of four tree species in a riparian forest habitat in Altai region:European aspen(Populus tremula),bitter poplar(Populus laurifolia),Swedish birch(Betula pendula),and Siberian spruce(Picea obovata).The results reveal that European aspen was insen-sitive to climate changes.In contrast,bitter poplar showed a positive response to elevated temperatures and negative to increased moisture during the growing season.Swedish birch and Siberian spruce were adversely affected by higher temperatures but benefited from increased precipitation.A moving correlation analysis suggested that,against a back-drop of continuous warming,growth patterns of these spe-cies will diverge:European aspen will require close moni-toring,bitter poplar may likely to show accelerated growth,and the growth of Swedish birch and Siberian spruce may be inhibited,leading to a decline.These findings offer insight into the future dynamics of riparian forests under changing climate.展开更多
Annual tree rings are widely recognized as valuable tools for quantifying and reconstructing historical forest disturbances.However,the influence of climate can complicate the detection of disturbance signals,leading ...Annual tree rings are widely recognized as valuable tools for quantifying and reconstructing historical forest disturbances.However,the influence of climate can complicate the detection of disturbance signals,leading to limited accuracy in existing methods.In this study,we propose a random under-sampling boosting(RUB)classifier that integrates both tree-ring and climate variables to enhance the detection of forest insect outbreaks.The study focused on 32 sites in Alberta,Canada,which documented insect outbreaks from 1939 to 2010.Through thorough feature engineering,model development,and tenfold cross-validation,multiple machine learning(ML)models were constructed.These models used ring width indices(RWIs)and climate variables within an 11-year window as input features,with outbreak and non-outbreak occurrences as the corresponding output variables.Our results reveal that the RUB model consistently demonstrated superior overall performance and stability,with an accuracy of 88.1%,which surpassed that of the other ML models.In addition,the relative importance of the feature variables followed the order RWIs>mean maximum temperature(Tmax)from May to July>mean total precipita-tion(Pmean)in July>mean minimum temperature(Tmin)in October.More importantly,the dfoliatR(an R package for detecting insect defoliation)and curve intervention detec-tion methods were inferior to the RUB model.Our findings underscore that integrating tree-ring width and climate vari-ables as predictors in machine learning offers a promising avenue for enhancing the accuracy of detecting forest insect outbreaks.展开更多
Background:Plasminogen activator inhibitor-1(PAI-1)plays an important role in the pathophysiology of sepsis,but the exact mechanism remains debatable.In this study,we investigated the associations among the serum leve...Background:Plasminogen activator inhibitor-1(PAI-1)plays an important role in the pathophysiology of sepsis,but the exact mechanism remains debatable.In this study,we investigated the associations among the serum levels of PAI-1,the incidence of 4G/5G promoter PAI-1 gene polymorphisms,immunological indicators,and clinical outcomes in septic patients.Methods:A total of 181 patients aged 18-80 years with sepsis between November 2016 and August 2018 in the intensive care unit in the Xinhua Hospital were recruited in this retrospective study,with 28-day mortality as the primary outcome.The initial serum level of PAI-1 and the presence of rs1799768 single nucleotide polymorphisms(SNPs)were examined.Univariate logistic regression and multivariate analyses were performed to determine the factors associated with different genotypes of PAI-1,serum level of PAI-1,and 28-day mortality.Results:The logistic analysis suggested that a high serum level of PAI-1 was associated with the rs1799768 SNP of PAI-1(4G/4G and 4G/5G)(Odds ratio[OR]:2.49;95%confidence interval[CI]:1.09,5.68).Furthermore,a high serum level of PAI-1 strongly influenced 28-day mortality(OR 3.36;95%CI 1.51,7.49).The expression and activation of neutrophils(OR 0.96;95%CI 0.93,0.99),as well as the changes in the expression patterns of cytokines and chemokine-associated neutrophils(OR:1.00;95%CI:1.00,1.00),were both regulated by the genotype of PAI-1.Conclusions:Genetic polymorphisms of PAI-1 can influence the serum levels of PAI-1,which might contribute to mortality by affecting neutrophil activity.Thus,patients with severe sepsis might clinically benefit from enhanced neutrophil clearance and the resolution of inflammation via the regulation of PAI-1 expression and activity.展开更多
Polarimetric imaging provides valuable insights into the polarization state of light interacting with a sample.It can infer crucial birefringence properties of specimens without using labels,thereby facilitating the d...Polarimetric imaging provides valuable insights into the polarization state of light interacting with a sample.It can infer crucial birefringence properties of specimens without using labels,thereby facilitating the diagnosis of diseases such as cancer and osteoarthritis.In this study,we present a novel polarimetric coded ptychography(pol-CP)approach that enables high-resolution,high-throughput gigapixel birefringence imaging on a chip.Our platform deviates from traditional lens-based systems by employing an integrated polarimetric coded sensor for lensless coherent diffraction imaging.Utilizing Jones calculus,we quantitatively determine the birefringence retardance and orientation information of biospecimens from the recovered images.Our portable pol-CP prototype can resolve the 435 nm linewidth on the resolution target,and the imaging field of view for a single acquisition is limited only by the detector size of 41 mm2.The prototype allows for the acquisition of gigapixel birefringence images with a 180 mm^(2) field of view in~3.5 min,a performance that rivals high-end whole slide scanner but at a small fraction of the cost.To demonstrate its biomedical applications,we perform high-throughput imaging of malaria-infected blood smears,locating parasites using birefringence contrast.We also generate birefringence maps of label-free thyroid smears to identify thyroid follicles.Notably,the recovered birefringence maps emphasize the same regions as autofluorescence images,underscoring the potential for rapid on-site evaluation of label-free biopsies.Our approach provides a turnkey and portable solution for lensless polarimetric analysis on a chip,with promising applications in disease diagnosis,crystal screening,and label-free chemical imaging,particularly in resource-constrained environments.展开更多
Background:We analyzed the success and catheter tip malposition rates of peripherally inserted central catheter(PICC)placement using ultrasonic monitoring.Methods:A total of 564 patients were recruited and assigned to...Background:We analyzed the success and catheter tip malposition rates of peripherally inserted central catheter(PICC)placement using ultrasonic monitoring.Methods:A total of 564 patients were recruited and assigned to either the intervention or control group.In the intervention group,282 patients underwent ultrasound-guided PICC insertion,which helped to identify the position and depth of the catheter tip.From a total of 9000 patients,282 were selectively chosen to receive the traditional method using body surface measurements(control group).The primary endpoint was the success rate;the secondary endpoint was the catheter tip malposition rate as detected by postprocedure chest radiography.Results:In the intervention group,a total of 94 catheters were in a suboptimal position;26 were too deep,68 were too shallow,and 1 was inserted into the subclavian vein,with success and malposition rates of 66.3%and 0.4%,respectively.In the control group,139 catheters were in a suboptimal position;88 were too deep,51 were too shallow,9 were inserted into the jugular vein,and 2 were inserted into the subclavian vein,with success and malposition rates of 46.8%(P<0.001)and 3.9%(P=0.004),respectively.Significant differences were observed in success and malposition rates between the 2 groups.Conclusion:Ultrasound-guided PICC procedures achieved higher success rates and lower malposition rates.展开更多
Large-scale computational imaging can provide remarkable space-bandwidth product that is beyond the limit of optical systems.In coherent imaging(CI),the joint reconstruction of amplitude and phase further expands the ...Large-scale computational imaging can provide remarkable space-bandwidth product that is beyond the limit of optical systems.In coherent imaging(CI),the joint reconstruction of amplitude and phase further expands the information throughput and sheds light on label-free observation of biological samples at micro-or even nano-levels.The existing large-scale CI techniques usually require scanning/modulation multiple times to guarantee measurement diversity and long exposure time to achieve a high signal-to-noise ratio.Such cumbersome procedures restrict clinical applications for rapid and lowphototoxicity cell imaging.In this work,a complex-domain-enhancing neural network for large-scale CI termed CI-CDNet is proposed for various large-scale CI modalities with satisfactory reconstruction quality and efficiency.CI-CDNet is able to exploit the latent coupling information between amplitude and phase(such as their same features),realizing multidimensional representations of the complex wavefront.The cross-field characterization framework empowers strong generalization and robustness for various coherent modalities,allowing high-quality and efficient imaging under extremely low exposure time and few data volume.We apply CI-CDNet in various large-scale CI modalities including Kramers–Kronigrelations holography,Fourier ptychographic microscopy,and lensless coded ptychography.A series of simulations and experiments validate that CI-CDNet can reduce exposure time and data volume by more than 1 order of magnitude.We further demonstrate that the high-quality reconstruction of CI-CDNet benefits the subsequent high-level semantic analysis.展开更多
Conventional ptychography translates an object through a localized probe beam to widen the field of view in real space.Fourier ptychography translates the object spectrum through a pupil aperture to expand the Fourier...Conventional ptychography translates an object through a localized probe beam to widen the field of view in real space.Fourier ptychography translates the object spectrum through a pupil aperture to expand the Fourier bandwidth in reciprocal space.Here we report an imaging modality,termed synthetic aperture ptychography(SAP),to get the best of both techniques.In SAP,we illuminate a stationary object using an extended plane wave and translate a coded image sensor at the far field for data acquisition.The coded layer attached on the sensor modulates the object exit waves and serves as an effective ptychographic probe for phase retrieval.The sensor translation process in SAP synthesizes a large complex-valued wavefront at the intermediate aperture plane.By propagating this wavefront back to the object plane,we can widen the field of view in real space and expand the Fourier bandwidth in reciprocal space simultaneously.We validate the SAP approach with transmission targets and reflection silicon microchips.A 20-mm aperture was synthesized using a 5-mm sensor,achieving a fourfold gain in resolution and 16-fold gain in field of view for object recovery.In addition,the thin sample requirement in ptychography is no longer required in SAP.One can digitally propagate the recovered exit wave to any axial position for post-acquisition refocusing.The SAP scheme offers a solution for far-field sub-diffraction imaging without using lenses.It can be adopted in coherent diffraction imaging setups with radiation sources from visible light,extreme ultraviolet,and X-ray,to electron.展开更多
Background:Recent studies suggest that acute kidney injury(AKI)can be treated with renal replacement therapy(RRT).However,its benefits to patients with sepsis-associated AKI(SA-AKI),which is linked to high mortality a...Background:Recent studies suggest that acute kidney injury(AKI)can be treated with renal replacement therapy(RRT).However,its benefits to patients with sepsis-associated AKI(SA-AKI),which is linked to high mortality and morbidity rates,remain under debate.The aim of this study was to compare the outcomes of different RRT strategies for patients with SA-AKI.Methods:This retrospective study evaluated patients who were admitted to the hospital with sepsis and devel-oped SA-AKI during hospitalization from 1st January 2014 to 31st January 2019.Mortality,renal recovery,and systemic organ function at 90 days following admission were compared between the RRT group(RG)and non-RRT group(NRG),as well as the early-RRT group(EG)and delayed-RRT group(DG).The groups were defined according to the time from admission to RRT initiation(criterion 1,EG1 and DG1)and Kidney Disease Improving Global Outcomes(KDIGO)classification(criterion 2,EG2 and DG2).Categorical and continuous variables were compared using the chi-squared test or Fisher’s exact test and Student’s t-test or Wilcoxon test.Kaplan-Meier curves were constructed to determine the unadjusted survival rates for the different subgroups.Results:A total of 116 patients were included in this study;of those,38 received RRT and 46 expired within 90 days.Among different strategies of RRT,there were no significant differences found in 90-day mortality(RG vs.NRG:𝜒2=0.610,P=0.435;EG1 vs.DG1:𝜒2=0.835,P=0.360;EG2 vs.DG2:𝜒2=0.022,P=0.899)and renal recovery.However,the values of change in sequential organ failure assessment(ΔSOFA)max-min of patients in the EG and RG were significantly higher than those recorded in the NRG(ΔSOFA RG=7.0,ΔSOFA NRG=3.60,ΔSOFA EG1=9.00,ΔSOFA EG2=6.30;P<0.050).Also,the 90-day renal recovery in the EG was better than that noted in the DG with criterion 1(87.5%vs.38.5%,respectively,𝜒2=10.425,P=0.032),suggesting that RRT(especially timely RRT)may be beneficial to the restoration of systemic organ function in patients with SA-AKI.Conclusion:RRT did not reduce the 90-day mortality among patients with SA-AKI.However,timely RRT may benefit the restoration of systemic organ function,thereby improving the quality of life of patients.展开更多
In most pathology labs,clinicians diagnose diseases by examining tissue slices using a light microscope.This process typically requires clinicians to move the microscope stage to different positions and identify areas...In most pathology labs,clinicians diagnose diseases by examining tissue slices using a light microscope.This process typically requires clinicians to move the microscope stage to different positions and identify areas of interest that can be further analyzed using a higher magnification objective lens.For proper focusing of the slide,the axial position needs to be constantly adjusted by manually rotating the focus knob.As a result,the reviewing process can be easily disrupted when the clinician bumps the slide to the objective lens or switches to a different objective lens for focusing again.Although it remains the gold standard in diagnosing almost all types of cancers,manual microscopic inspection is,in general,labor-intensive and does not form a streamlined workflow in clinical practice.Furthermore,it is largely based on subjective opinions of clinicians:different clinicians may arrive at different conclusions for the same slide and the same person may give different conclusions at different time points[1].展开更多
Synthetic aperture radar(SAR)utilizes an aircraft-carried antenna to emit electromagnetic pulses and detect the returning echoes.As the aircraft travels across a designated area,it synthesizes a large virtual aperture...Synthetic aperture radar(SAR)utilizes an aircraft-carried antenna to emit electromagnetic pulses and detect the returning echoes.As the aircraft travels across a designated area,it synthesizes a large virtual aperture to improve image resolution.Inspired by SAR,we introduce synthetic aperture ptycho-endoscopy(SAPE)for micro-endoscopic imaging beyond the diffraction limit.SAPE operates by hand-holding a lensless fiber bundle tip to record coherent diffraction patterns from specimens.The fiber cores at the distal tip modulate the diffracted wavefield within a confined area,emulating the role of the‘airborne antenna’in SAR.The handheld operation introduces positional shifts to the tip,analogous to the aircraft’s movement.These shifts facilitate the acquisition of a ptychogram and synthesize a large virtual aperture extending beyond the bundle’s physical limit.We mitigate the influences of hand motion and fiber bending through a low-rank spatiotemporal decomposition of the bundle’s modulation profile.Our tests demonstrate the ability to resolve a 548-nm linewidth on a resolution target.The achieved space-bandwidth product is~1.1 million effective pixels,representing a 36-fold increase compared to that of the original fiber bundle.Furthermore,SAPE’s refocusing capability enables imaging over an extended depth of field exceeding 2 cm.The aperture synthesizing process in SAPE surpasses the diffraction limit set by the probe’s maximum collection angle,opening new opportunities for both fiber-based and distal-chip endoscopy in applications such as medical diagnostics and industrial inspection.展开更多
基金supported by the Natural Science Foundation of Shanxi Province(202203021221008)the Special Funding for Shanxi Provincial Science and Technology Innovation Talent Team(202204051001010)the National Natural Science Foundation of China(41701047).
文摘In the context of ongoing climate change,rela-tionships between tree growth and climate present uncertain-ties,which limits the predictions of future forest dynamics.Northwest China is a region undergoing notable warming and increased precipitation;how forests in this region will respond to climate change has not been fully understood.We used dendrochronological methods to examine the rela-tionship between climate and the radial growth of four tree species in a riparian forest habitat in Altai region:European aspen(Populus tremula),bitter poplar(Populus laurifolia),Swedish birch(Betula pendula),and Siberian spruce(Picea obovata).The results reveal that European aspen was insen-sitive to climate changes.In contrast,bitter poplar showed a positive response to elevated temperatures and negative to increased moisture during the growing season.Swedish birch and Siberian spruce were adversely affected by higher temperatures but benefited from increased precipitation.A moving correlation analysis suggested that,against a back-drop of continuous warming,growth patterns of these spe-cies will diverge:European aspen will require close moni-toring,bitter poplar may likely to show accelerated growth,and the growth of Swedish birch and Siberian spruce may be inhibited,leading to a decline.These findings offer insight into the future dynamics of riparian forests under changing climate.
基金supported by the Xinjiang Regional Collaborative Innovation Project(2022E01045)Zhejiang University(108000*1942222R1).
文摘Annual tree rings are widely recognized as valuable tools for quantifying and reconstructing historical forest disturbances.However,the influence of climate can complicate the detection of disturbance signals,leading to limited accuracy in existing methods.In this study,we propose a random under-sampling boosting(RUB)classifier that integrates both tree-ring and climate variables to enhance the detection of forest insect outbreaks.The study focused on 32 sites in Alberta,Canada,which documented insect outbreaks from 1939 to 2010.Through thorough feature engineering,model development,and tenfold cross-validation,multiple machine learning(ML)models were constructed.These models used ring width indices(RWIs)and climate variables within an 11-year window as input features,with outbreak and non-outbreak occurrences as the corresponding output variables.Our results reveal that the RUB model consistently demonstrated superior overall performance and stability,with an accuracy of 88.1%,which surpassed that of the other ML models.In addition,the relative importance of the feature variables followed the order RWIs>mean maximum temperature(Tmax)from May to July>mean total precipita-tion(Pmean)in July>mean minimum temperature(Tmin)in October.More importantly,the dfoliatR(an R package for detecting insect defoliation)and curve intervention detec-tion methods were inferior to the RUB model.Our findings underscore that integrating tree-ring width and climate vari-ables as predictors in machine learning offers a promising avenue for enhancing the accuracy of detecting forest insect outbreaks.
基金supported by grants from the National Natural Science Foundation of China(Nos.82172138 and 81873947)Special Medical Innovation Project of Shanghai Science and Technology Committee(No.21Y11902400)the Key Laboratory of Emergency and Trauma(Hainan Medical University),Ministry of Education(No.KLET-202016)
文摘Background:Plasminogen activator inhibitor-1(PAI-1)plays an important role in the pathophysiology of sepsis,but the exact mechanism remains debatable.In this study,we investigated the associations among the serum levels of PAI-1,the incidence of 4G/5G promoter PAI-1 gene polymorphisms,immunological indicators,and clinical outcomes in septic patients.Methods:A total of 181 patients aged 18-80 years with sepsis between November 2016 and August 2018 in the intensive care unit in the Xinhua Hospital were recruited in this retrospective study,with 28-day mortality as the primary outcome.The initial serum level of PAI-1 and the presence of rs1799768 single nucleotide polymorphisms(SNPs)were examined.Univariate logistic regression and multivariate analyses were performed to determine the factors associated with different genotypes of PAI-1,serum level of PAI-1,and 28-day mortality.Results:The logistic analysis suggested that a high serum level of PAI-1 was associated with the rs1799768 SNP of PAI-1(4G/4G and 4G/5G)(Odds ratio[OR]:2.49;95%confidence interval[CI]:1.09,5.68).Furthermore,a high serum level of PAI-1 strongly influenced 28-day mortality(OR 3.36;95%CI 1.51,7.49).The expression and activation of neutrophils(OR 0.96;95%CI 0.93,0.99),as well as the changes in the expression patterns of cytokines and chemokine-associated neutrophils(OR:1.00;95%CI:1.00,1.00),were both regulated by the genotype of PAI-1.Conclusions:Genetic polymorphisms of PAI-1 can influence the serum levels of PAI-1,which might contribute to mortality by affecting neutrophil activity.Thus,patients with severe sepsis might clinically benefit from enhanced neutrophil clearance and the resolution of inflammation via the regulation of PAI-1 expression and activity.
基金National Natural Science Foundation of China(61975254,62075175)。
文摘Polarimetric imaging provides valuable insights into the polarization state of light interacting with a sample.It can infer crucial birefringence properties of specimens without using labels,thereby facilitating the diagnosis of diseases such as cancer and osteoarthritis.In this study,we present a novel polarimetric coded ptychography(pol-CP)approach that enables high-resolution,high-throughput gigapixel birefringence imaging on a chip.Our platform deviates from traditional lens-based systems by employing an integrated polarimetric coded sensor for lensless coherent diffraction imaging.Utilizing Jones calculus,we quantitatively determine the birefringence retardance and orientation information of biospecimens from the recovered images.Our portable pol-CP prototype can resolve the 435 nm linewidth on the resolution target,and the imaging field of view for a single acquisition is limited only by the detector size of 41 mm2.The prototype allows for the acquisition of gigapixel birefringence images with a 180 mm^(2) field of view in~3.5 min,a performance that rivals high-end whole slide scanner but at a small fraction of the cost.To demonstrate its biomedical applications,we perform high-throughput imaging of malaria-infected blood smears,locating parasites using birefringence contrast.We also generate birefringence maps of label-free thyroid smears to identify thyroid follicles.Notably,the recovered birefringence maps emphasize the same regions as autofluorescence images,underscoring the potential for rapid on-site evaluation of label-free biopsies.Our approach provides a turnkey and portable solution for lensless polarimetric analysis on a chip,with promising applications in disease diagnosis,crystal screening,and label-free chemical imaging,particularly in resource-constrained environments.
基金supported by the National Natural Science Foundation of China(82172138 and 81873947)Special Medical Innovation Project of Shanghai Science and Technology Committee(no.21Y11902400)+1 种基金Excellent Academic Leader Program of Shanghai Science and Technology Committee(21XD1402200)Key Laboratory of Emergency and Trauma(Hainan Medical University),Ministry of Education(grant KLET-202016).
文摘Background:We analyzed the success and catheter tip malposition rates of peripherally inserted central catheter(PICC)placement using ultrasonic monitoring.Methods:A total of 564 patients were recruited and assigned to either the intervention or control group.In the intervention group,282 patients underwent ultrasound-guided PICC insertion,which helped to identify the position and depth of the catheter tip.From a total of 9000 patients,282 were selectively chosen to receive the traditional method using body surface measurements(control group).The primary endpoint was the success rate;the secondary endpoint was the catheter tip malposition rate as detected by postprocedure chest radiography.Results:In the intervention group,a total of 94 catheters were in a suboptimal position;26 were too deep,68 were too shallow,and 1 was inserted into the subclavian vein,with success and malposition rates of 66.3%and 0.4%,respectively.In the control group,139 catheters were in a suboptimal position;88 were too deep,51 were too shallow,9 were inserted into the jugular vein,and 2 were inserted into the subclavian vein,with success and malposition rates of 46.8%(P<0.001)and 3.9%(P=0.004),respectively.Significant differences were observed in success and malposition rates between the 2 groups.Conclusion:Ultrasound-guided PICC procedures achieved higher success rates and lower malposition rates.
基金supported by the National Natural Science Foundation of China(Grant Nos.61827901,61991451,62131003)the BIT Research and Innovation Promoting Project(Grant No.2022YCXZ006).
文摘Large-scale computational imaging can provide remarkable space-bandwidth product that is beyond the limit of optical systems.In coherent imaging(CI),the joint reconstruction of amplitude and phase further expands the information throughput and sheds light on label-free observation of biological samples at micro-or even nano-levels.The existing large-scale CI techniques usually require scanning/modulation multiple times to guarantee measurement diversity and long exposure time to achieve a high signal-to-noise ratio.Such cumbersome procedures restrict clinical applications for rapid and lowphototoxicity cell imaging.In this work,a complex-domain-enhancing neural network for large-scale CI termed CI-CDNet is proposed for various large-scale CI modalities with satisfactory reconstruction quality and efficiency.CI-CDNet is able to exploit the latent coupling information between amplitude and phase(such as their same features),realizing multidimensional representations of the complex wavefront.The cross-field characterization framework empowers strong generalization and robustness for various coherent modalities,allowing high-quality and efficient imaging under extremely low exposure time and few data volume.We apply CI-CDNet in various large-scale CI modalities including Kramers–Kronigrelations holography,Fourier ptychographic microscopy,and lensless coded ptychography.A series of simulations and experiments validate that CI-CDNet can reduce exposure time and data volume by more than 1 order of magnitude.We further demonstrate that the high-quality reconstruction of CI-CDNet benefits the subsequent high-level semantic analysis.
文摘Conventional ptychography translates an object through a localized probe beam to widen the field of view in real space.Fourier ptychography translates the object spectrum through a pupil aperture to expand the Fourier bandwidth in reciprocal space.Here we report an imaging modality,termed synthetic aperture ptychography(SAP),to get the best of both techniques.In SAP,we illuminate a stationary object using an extended plane wave and translate a coded image sensor at the far field for data acquisition.The coded layer attached on the sensor modulates the object exit waves and serves as an effective ptychographic probe for phase retrieval.The sensor translation process in SAP synthesizes a large complex-valued wavefront at the intermediate aperture plane.By propagating this wavefront back to the object plane,we can widen the field of view in real space and expand the Fourier bandwidth in reciprocal space simultaneously.We validate the SAP approach with transmission targets and reflection silicon microchips.A 20-mm aperture was synthesized using a 5-mm sensor,achieving a fourfold gain in resolution and 16-fold gain in field of view for object recovery.In addition,the thin sample requirement in ptychography is no longer required in SAP.One can digitally propagate the recovered exit wave to any axial position for post-acquisition refocusing.The SAP scheme offers a solution for far-field sub-diffraction imaging without using lenses.It can be adopted in coherent diffraction imaging setups with radiation sources from visible light,extreme ultraviolet,and X-ray,to electron.
文摘Background:Recent studies suggest that acute kidney injury(AKI)can be treated with renal replacement therapy(RRT).However,its benefits to patients with sepsis-associated AKI(SA-AKI),which is linked to high mortality and morbidity rates,remain under debate.The aim of this study was to compare the outcomes of different RRT strategies for patients with SA-AKI.Methods:This retrospective study evaluated patients who were admitted to the hospital with sepsis and devel-oped SA-AKI during hospitalization from 1st January 2014 to 31st January 2019.Mortality,renal recovery,and systemic organ function at 90 days following admission were compared between the RRT group(RG)and non-RRT group(NRG),as well as the early-RRT group(EG)and delayed-RRT group(DG).The groups were defined according to the time from admission to RRT initiation(criterion 1,EG1 and DG1)and Kidney Disease Improving Global Outcomes(KDIGO)classification(criterion 2,EG2 and DG2).Categorical and continuous variables were compared using the chi-squared test or Fisher’s exact test and Student’s t-test or Wilcoxon test.Kaplan-Meier curves were constructed to determine the unadjusted survival rates for the different subgroups.Results:A total of 116 patients were included in this study;of those,38 received RRT and 46 expired within 90 days.Among different strategies of RRT,there were no significant differences found in 90-day mortality(RG vs.NRG:𝜒2=0.610,P=0.435;EG1 vs.DG1:𝜒2=0.835,P=0.360;EG2 vs.DG2:𝜒2=0.022,P=0.899)and renal recovery.However,the values of change in sequential organ failure assessment(ΔSOFA)max-min of patients in the EG and RG were significantly higher than those recorded in the NRG(ΔSOFA RG=7.0,ΔSOFA NRG=3.60,ΔSOFA EG1=9.00,ΔSOFA EG2=6.30;P<0.050).Also,the 90-day renal recovery in the EG was better than that noted in the DG with criterion 1(87.5%vs.38.5%,respectively,𝜒2=10.425,P=0.032),suggesting that RRT(especially timely RRT)may be beneficial to the restoration of systemic organ function in patients with SA-AKI.Conclusion:RRT did not reduce the 90-day mortality among patients with SA-AKI.However,timely RRT may benefit the restoration of systemic organ function,thereby improving the quality of life of patients.
文摘In most pathology labs,clinicians diagnose diseases by examining tissue slices using a light microscope.This process typically requires clinicians to move the microscope stage to different positions and identify areas of interest that can be further analyzed using a higher magnification objective lens.For proper focusing of the slide,the axial position needs to be constantly adjusted by manually rotating the focus knob.As a result,the reviewing process can be easily disrupted when the clinician bumps the slide to the objective lens or switches to a different objective lens for focusing again.Although it remains the gold standard in diagnosing almost all types of cancers,manual microscopic inspection is,in general,labor-intensive and does not form a streamlined workflow in clinical practice.Furthermore,it is largely based on subjective opinions of clinicians:different clinicians may arrive at different conclusions for the same slide and the same person may give different conclusions at different time points[1].
基金supported by the National Institute of Health R01-EB034744(G.Z.)the UConn SPARK grant(G.Z.),National Science Foundation 2012140(G.Z.)the National Institute of Health U01-NS113873(B.F.and G.Z.).
文摘Synthetic aperture radar(SAR)utilizes an aircraft-carried antenna to emit electromagnetic pulses and detect the returning echoes.As the aircraft travels across a designated area,it synthesizes a large virtual aperture to improve image resolution.Inspired by SAR,we introduce synthetic aperture ptycho-endoscopy(SAPE)for micro-endoscopic imaging beyond the diffraction limit.SAPE operates by hand-holding a lensless fiber bundle tip to record coherent diffraction patterns from specimens.The fiber cores at the distal tip modulate the diffracted wavefield within a confined area,emulating the role of the‘airborne antenna’in SAR.The handheld operation introduces positional shifts to the tip,analogous to the aircraft’s movement.These shifts facilitate the acquisition of a ptychogram and synthesize a large virtual aperture extending beyond the bundle’s physical limit.We mitigate the influences of hand motion and fiber bending through a low-rank spatiotemporal decomposition of the bundle’s modulation profile.Our tests demonstrate the ability to resolve a 548-nm linewidth on a resolution target.The achieved space-bandwidth product is~1.1 million effective pixels,representing a 36-fold increase compared to that of the original fiber bundle.Furthermore,SAPE’s refocusing capability enables imaging over an extended depth of field exceeding 2 cm.The aperture synthesizing process in SAPE surpasses the diffraction limit set by the probe’s maximum collection angle,opening new opportunities for both fiber-based and distal-chip endoscopy in applications such as medical diagnostics and industrial inspection.