BACKGROUND Primary ciliary dyskinesia(PCD)is a rare genetic disorder caused by motile cilia dysfunction.Identifying pathogenic variants is essential for diagnosis and personalized care,especially in consanguineous pop...BACKGROUND Primary ciliary dyskinesia(PCD)is a rare genetic disorder caused by motile cilia dysfunction.Identifying pathogenic variants is essential for diagnosis and personalized care,especially in consanguineous populations like Saudi Arabia.CASE SUMMARY This report presents a Saudi pediatric patient diagnosed with PCD who exhibited persistent neonatal tachypnea,chronic productive cough,and recurrent otitis media.Whole-exome sequencing revealed a novel homozygous nonsense variant in the C3orf67 gene(NM_198463.2:c.508C>T),resulting in a truncated,nonfunctional protein.This mutation likely impairs ciliary motility due to the production of a truncated,non-functional protein.The clinical findings were supported by multiple positive sputum cultures and a significant family history of similar symptoms,suggesting a genetic etiology consistent with autosomal recessive inheritance.CONCLUSION This case highlights the importance of genetic studies in diagnosing PCD,particularly in communities with a high rate of consanguinity.The identification of a novel homozygous variant in the C3orf67 gene expands the known genetic landscape of the disease.Further research is essential to clarify the functional role of C3orf67 in ciliary biology and its contribution to PCD pathogenesis.展开更多
First-order proximal methods that solve linear and bilinear elliptic optimal control problems with a sparsity cost functional are discussed. In particular, fast convergence of these methods is proved. For benchmarking...First-order proximal methods that solve linear and bilinear elliptic optimal control problems with a sparsity cost functional are discussed. In particular, fast convergence of these methods is proved. For benchmarking purposes, inexact proximal schemes are compared to an inexact semismooth Newton method. Results of numerical experiments are presented to demonstrate the computational effectiveness of proximal schemes applied to infinite-dimensional elliptic optimal control problems and to validate the theoretical estimates.展开更多
Hierarchical Si C nanowire-supported Pd nanoparticles showed high photocatalytic activity for the C–X(X = Br, I) borylation of aryl halides at 30 °C. The Si C/Pd Mott-Schottky contact enhances the rapid transfer...Hierarchical Si C nanowire-supported Pd nanoparticles showed high photocatalytic activity for the C–X(X = Br, I) borylation of aryl halides at 30 °C. The Si C/Pd Mott-Schottky contact enhances the rapid transfer of the photogenerated electrons from Si C to the Pd nanoparticles. As a result, the concentrated energetic electrons in the Pd nanoparticles can facilitate the cleavage of C–I or C–Br bonds, which normally requires high-temperature thermal processes. We show that the present Pd/Si C photocatalyst is capable of catalyzing the transformation of a large variety of aryl halides to their corresponding boronate esters under visible light irradiation, with excellent yields.展开更多
An efficient multigrid finite-differences scheme for solving elliptic Fredholm partial integro-differential equations (PIDE) is discussed. This scheme combines a second-order accurate finite difference discretization ...An efficient multigrid finite-differences scheme for solving elliptic Fredholm partial integro-differential equations (PIDE) is discussed. This scheme combines a second-order accurate finite difference discretization of the PIDE problem with a multigrid scheme that includes a fast multilevel integration of the Fredholm operator allowing the fast solution of the PIDE problem. Theoretical estimates of second-order accuracy and results of local Fourier analysis of convergence of the proposed multigrid scheme are presented. Results of numerical experiments validate these estimates and demonstrate optimal computational complexity of the proposed framework.展开更多
A mathematical optimal-control tumor therapy framework consisting of radio- and anti-angiogenesis control strategies that are included in a tumor growth model is investigated. The governing system, resulting from the ...A mathematical optimal-control tumor therapy framework consisting of radio- and anti-angiogenesis control strategies that are included in a tumor growth model is investigated. The governing system, resulting from the combination of two well established models, represents the differential constraint of a non-smooth optimal control problem that aims at reducing the volume of the tumor while keeping the radio- and anti-angiogenesis chemical dosage to a minimum. Existence of optimal solutions is proved and necessary conditions are formulated in terms of the Pontryagin maximum principle. Based on this principle, a so-called sequential quadratic Hamiltonian (SQH) method is discussed and benchmarked with an “interior point optimizer—a mathematical programming language” (IPOPT-AMPL) algorithm. Results of numerical experiments are presented that successfully validate the SQH solution scheme. Further, it is shown how to choose the optimisation weights in order to obtain treatment functions that successfully reduce the tumor volume to zero.展开更多
A framework for the optimal sparse-control of the probability density function of a jump-diffusion process is presented. This framework is based on the partial integro-differential Fokker-Planck (FP) equation that gov...A framework for the optimal sparse-control of the probability density function of a jump-diffusion process is presented. This framework is based on the partial integro-differential Fokker-Planck (FP) equation that governs the time evolution of the probability density function of this process. In the stochastic process and, correspondingly, in the FP model the control function enters as a time-dependent coefficient. The objectives of the control are to minimize a discrete-in-time, resp. continuous-in-time, tracking functionals and its L2- and L1-costs, where the latter is considered to promote control sparsity. An efficient proximal scheme for solving these optimal control problems is considered. Results of numerical experiments are presented to validate the theoretical results and the computational effectiveness of the proposed control framework.展开更多
<div style="text-align:justify;"> <span style="font-family:Verdana;">Though many different readability metrics have been created, there still is no universal agreement defining readabil...<div style="text-align:justify;"> <span style="font-family:Verdana;">Though many different readability metrics have been created, there still is no universal agreement defining readability of software source code. The lack of a clear agreement of source code readability has ramifications in many areas of the software development life-cycle, not least of which being software maintainability. We propose a measurement based on Linguistic Economy to bridge the gap between mathematical and behavioral aspects. Linguistic Economy describes efficiencies of speech and is generally applied to natural languages. In our study, we create a large corpus of words that are likely to be found in a programmer’s vocabulary, and a corpus of existing identifiers found in a collection of open-source projects. We perform a usage analysis to create a database from both of these corpora. Linguistic Economy suggests that words requiring less effort to speak are used more often than words requiring more effort. This concept is applied to measure how difficult program identifiers are to understand by extracting them from the program source and comparing their usage to the database. Through this process, we can identify source code that programmers find difficult to review. We validate our work using data from a survey where programmers identified unpleasant to review source files. The results indicate that source files identified as unpleasant to review source code have more linguistically complicated identifiers than pleasant programs.</span> </div>展开更多
A remarkable study by Guo et al.,published in Cell,suggests a compelling new direction for improving pain management:biased allosteric modulation of the neurotensin receptor 1(NTSR1),using the drug-like molecule SBI-8...A remarkable study by Guo et al.,published in Cell,suggests a compelling new direction for improving pain management:biased allosteric modulation of the neurotensin receptor 1(NTSR1),using the drug-like molecule SBI-810,promotesβ-arrestin2(βarr2)recruitment while avoiding canonical G protein signaling–thereby providing robust analgesia across a plethora of rodent models of both acute and chronic pain without impairing motor function,cognition,or causing opioid-like dependency.1,2 SBI-810 is introduced as a highly promising molecule underscoring the therapeutic potential of biased and allosteric G protein-coupled receptor(GPCR)ligands to address an urgent unmet medical need.展开更多
Fluids in the deep subduction zones play an important role in crust-mantle ex-change related to the subduction process. Identification of fluids origin, internal or external, can help us to evaluate the contribution o...Fluids in the deep subduction zones play an important role in crust-mantle ex-change related to the subduction process. Identification of fluids origin, internal or external, can help us to evaluate the contribution of crust materials to mantle during this process. High-pressure veins, which developed in the western Tianshan HP-metamorphic belt extensively, are the direct products of the fluids in subduction zones. In western Tianshan, high-pressure veins and host rocks have overall Pb- and Sr-isotope compositions. At t = 340 Ma, the high-pressure metamorphic time, the ratios of 206Pb/204Pb, 207Pb/204Pb, 208Pb/204Pb and 87Sr/86Sr of high pressure veins are 17.122―18.431, 15.477―15.611, 37.432―38.689 and 0.70529―0.70705, and are 17.605―17.834, 15.508―15.564, 37.080―38.145 and 0.70522―0.70685 for host rocks. However, high-pressure veins show a much larger variation in Pb-isotope composi-tions than host rocks. Plots of samples are distributed roughly along a line parallel to and far away from the Northern Hemisphere reference line (NHRL) on the plot of 206Pb/204Pb vs 207Pb/204Pb. On the plot of 206Pb/204Pb vs 208Pb/204Pb, plots of data are distributed nearby mid-ocean-ridge basalts (MORB) area or along a line parallel to and not far away from NHRL, which shows that the data plots are farther away from MORB and ocean island basalts (OIB) areas on the plot of 206Pb/204Pb vs 207Pb/204Pb than on the plot of 206Pb/204Pb vs 208Pb/204Pb. The compositions of Pb- and Sr-isotopes of these high-pressure metamorphic rocks are between that of enriched mantle 1(EMI) and of sediments or upper crust. A notable characteristic can be seen from plots of Pb-isotope ratio vs Pb-isotope ratio and 206Pb/204Pb vs 87Sr/86Sr that array of plots shows an evident tendency of mixture of two end members. Ratios of Rb/Ba, Ce/Pb, Nb/U and Ta/U of high-pressure veins and host rocks are between that of OIB or MORB and that of conti-nental crust, which indicates that continental crust materials probably have been incorporated into the rocks. The fluids in the paleosubduction zones in western Tianshan are mixtures of two sources, one originating from the devolatilzation of the host rocks with protolithes similar to ocean basalts from enriched mantle 1 (EMI), the other from the dehydration of subducted sediments.展开更多
The Kachchh Basin and the Jaisalmer Basin are two neighboring Mesozoic sedimentary basins at the western margin of the Indian craton. The Jurassic succession of the Kachchh Basin is more complete and more fossiliferou...The Kachchh Basin and the Jaisalmer Basin are two neighboring Mesozoic sedimentary basins at the western margin of the Indian craton. The Jurassic succession of the Kachchh Basin is more complete and more fossiliferous than that of the Jaisalmer Basin. Consequently, intrabasinal correlation of the sedimentary units has been possible in the Kachchh Basin, but not in the Jaisalmer Basin. However, some marker beds existing in the Kachchh Basin can be recognized also in the Jaisalmer Basin. Ammonite evidence shows that they are time-equivalent. The following four units form marker intervals in both basins: (1) the pebbly rudstone unit with Isastrea bernardiana and Leptosphinctes of the Kaladongar Formation (Kachchh Basin) and the Isastrea bernardiana-bearing rudstone of the Jaisalmer Formation (Jaisalmer Basin) both represent transgressive systems tract deposits dated as Late Bajocian; (2) bioturbated micrites with anomalodesmatan bivalves within the Goradongar Yellow Flagstone Member (Kachchh Basin) and bioturbated units in the Fort Member (Jaisalmer Basin) represent maximum flooding zone deposits of the Middle to Late Bathonian; (3) trough-crossbedded, sandy packto grainstones of the Raimalro Limestone Member (Kachchh Basin) and the basal limestone-sandstone unit of the Kuldhar section of the Jaisalmer Formation (Jaisalmer Basin) correspond to Late Bathonain transgressive systems tract deposits; and (4) ferruginous ooid-bearing carbonates with hardgrounds of the Dhosa Oolite member (Kachchh Basin) and the middle part of the Jajiya Member (Jaisalmer Basin) are Oxfordian transgressive systems tract deposits. The fact that in both basins similar biofacies prevailed during certain time intervals demonstrates a common control of their depositional history. As the two basins represent different tectonic settings, the most likely controlling factors were the relative sea-level changes produced by eustatic processes, a common subsidence history of the northwestern margin of the Indian craton, and the paleoclimate.展开更多
GaN nanowires have been grown by molecular beam epitaxy either catalyst-free or catalyst-induced by means of Ni seeds.Under identical growth conditions of temperature andⅤ/Ⅲratio,both types of GaN nanowires are of w...GaN nanowires have been grown by molecular beam epitaxy either catalyst-free or catalyst-induced by means of Ni seeds.Under identical growth conditions of temperature andⅤ/Ⅲratio,both types of GaN nanowires are of wurtzite structure elongated in the Ga-polar direction and are constricted by M-plane facets.However,the catalyst-induced nanowires contain many more basal-plane stacking faults and their photoluminescence is weaker.These differences can be explained as effects of the catalyst Ni seeds.展开更多
Radiationless energy transfer is at the core of diverse phenomena,such as light harvesting in photosynthesis1,energy-transfer-based microspectroscopies2,nanoscale quantum entanglement3 and photonic-mode hybridization4...Radiationless energy transfer is at the core of diverse phenomena,such as light harvesting in photosynthesis1,energy-transfer-based microspectroscopies2,nanoscale quantum entanglement3 and photonic-mode hybridization4.Typically,the transfer is efficient only for separations that are much shorter than the diffraction limit.This hampers its application in optical communication and quantum information processing,which require spatially selective addressing.Here,we demonstrate highly efficient radiationless coherent energy transfer over a distance of twice the excitation wavelength by combining localized and delocalized5 plasmonic modes.Analogous to the Tavis–Cummings model,two whispering-gallery-mode antennas6 placed in the foci of an elliptical plasmonic cavity7 fabricated from single-crystal gold plates act as a pair of oscillators coupled to a common cavity mode.Time-resolved two-photon photoemission electron microscopy(TR 2P-PEEM)reveals an ultrafast long-range periodic energy transfer in accordance with the simulations.Our observations open perspectives for the optimization and tailoring of mesoscopic energy transfer and long-range quantum emitter coupling.展开更多
Background:Dispersal is an important event for most organisms at least once in their life cycle.The evolution of dispersal can be infuenced by local adaptation,landscape structure,and perceived temporal and spatial va...Background:Dispersal is an important event for most organisms at least once in their life cycle.The evolution of dispersal can be infuenced by local adaptation,landscape structure,and perceived temporal and spatial variation.The interaction between local adaptation,landscape heterogeneity,temporal variability and rules of dispersal may be more complex than previously assumed.Therefore,we sought to understand the infuence of emigration rules and landscape structure on emerging dispersal rates and traits.Here,we implemented an individual-based model(IBM)of trait evolution in scenarios characterized by diferent landscape structures and diferent degrees of spatial heterogeneity and global temporal variation.Individuals could evolve two traits coding for their environmental niche(position of niche optimum and niche width),and two traits determining nearest-neighbor dispersal:an individual emigrates with a probability defned by the frst trait(random emigration),but emigrates with certainty if the fertility expected in the patch of residence falls below a threshold specifed by the second trait(habitat-dependent emigration).Results:We note an interaction efect between dispersal strategy and spatial variance—lower emigration under habitat-dependent than under random emigration if spatial heterogeneity is low,but eventually a reversal of this ranking if heterogeneity becomes large.Landscapes with sharp transition of habitat attributes result in a high degree of spatial sorting,while fractal landscapes do not.Emigration rates are overall lowest,when spatial variation is highest.Conclusions:We conclude that emergent emigration rates are infuenced more by landscape structure and spatiotemporal heterogeneity than by the emigration strategy.With the ongoing land use change more research into this topic could help highlight the difculties species might face under the change from landscapes characterized by gradual transition zones to landscapes dominated by abrupt ecotones,the latter typical for agricultural and urban settings.展开更多
Machine learning(ML)techniques have made enormous progress in the field of materials science.However,many conventional ML algorithms operate as“blackboxes”,lacking transparency in revealing explicit relationships be...Machine learning(ML)techniques have made enormous progress in the field of materials science.However,many conventional ML algorithms operate as“blackboxes”,lacking transparency in revealing explicit relationships between material features and target properties.To address this,the development of interpretable ML models is essential to drive further advancements in AI-driven materials discovery.In this study,we present an interpretable framework that combines traditional machine learning with symbolic regression,using Janus III–VI vdW heterostructures as a case study.This approach enables fast and accurate predictions of stability and electronic structure.Our results demonstrate that the prediction accuracy using the classification model for stability,based on formation energy,reaches 0.960.On the other hand,the R2,MAE,and RMSE value using the regression model for electronic structure prediction,based on band gap,achieves 0.927,0.113,and 0.141 on the testing set,respectively.Additionally,we identify a universal interpretable descriptor comprising five simple parameters that reveals the underlying physical relationships between the candidate heterostructures and their band gaps.This descriptor not only delivers high accuracy in band gap prediction but also provides explicit physical insight into the material properties.展开更多
Superconductor-semiconductor hybrid devices can bridge the gap between solid-state-based and photonics-based quantum systems,enabling new hybrid computing schemes,offering increased scalability and robustness.One exam...Superconductor-semiconductor hybrid devices can bridge the gap between solid-state-based and photonics-based quantum systems,enabling new hybrid computing schemes,offering increased scalability and robustness.One example for a hybrid device is the superconducting light-emitting diode(SLED).SLEDs have been theoretically shown to emit polarization-entangled photon pairs by utilizing radiative recombination of Cooper pairs.However,the twophoton nature of the emission has not been shown experimentally before.We demonstrate two-photon emission in a GaAs/AlGaAs SLED.Measured electroluminescence spectra reveal unique two-photon superconducting features below the critical temperature(Tc),while temperature-dependent photon-pair correlation experiments(g(2)(τ,T))demonstrate temperature-dependent time coincidences below Tc between photons emitted from the SLED.Our results pave the way for compact and efficient superconducting quantum light sources and open new directions in light-matter interaction studies.展开更多
Two-level emitters are the main building blocks of photonic quantum technologies and are model systems for the exploration of quantum optics in the solid state.Most interesting is the strict resonant excitation of suc...Two-level emitters are the main building blocks of photonic quantum technologies and are model systems for the exploration of quantum optics in the solid state.Most interesting is the strict resonant excitation of such emitters to control their occupation coherently and to generate close to ideal quantum light,which is of utmost importance for applications in photonic quantum technology.To date,the approaches and experiments in this field have been performed exclusively using bulky lasers,which hinders the application of resonantly driven two-level emitters in compact photonic quantum systems.Here we address this issue and present a concept for a compact resonantly driven single-photon source by performing quantum-optical spectroscopy of a two-level system using a compact high-βmicrolaser as the excitation source.The two-level system is based on a semiconductor quantum dot(QD),which is excited resonantly by a fiber-coupled electrically driven micropillar laser.We dress the excitonic state of the QD under continuous wave excitation,and trigger the emission of single photons with strong multi-photon suppression(ge2Te0T?0:02)and high photon indistinguishability(V=57±9%)via pulsed resonant excitation at 156 MHz.These results clearly demonstrate the high potential of our resonant excitation scheme,which can pave the way for compact electrically driven quantum light sources with excellent quantum properties to enable the implementation of advanced quantum communication protocols.展开更多
Headwater streams play a major role for provision of ecosystem services,e.g.drinking water.We investigated a high-altitude headwater catchment of the Kharaa River(including 411st-order rivers)to understand the impact ...Headwater streams play a major role for provision of ecosystem services,e.g.drinking water.We investigated a high-altitude headwater catchment of the Kharaa River(including 411st-order rivers)to understand the impact of land cover(especially forest cover),environment and human usage on runoff,chemical water quality and macroinvertebrate fauna in a river basin under discontinuous permafrost conditions in an arid,sparsely populated region of Mongolia.To verify our hypotheses that different landuses and environmental impacts in permafrost headwaters influence water quality,we investigated 105 sampling sites,37 of them at intermittent stream sections without water flow.Discharge was positively impacted by land cover types steppe,grassland and forest and negatively by shrubland,forest burnt by wild fires(indicating a reduction of permafrost)and slope.Water quality was affected by altitude,longitude and latitude,shrub growth and water temperature.Shannon diversity of macroinvertebrates was driven by water temperature,iron content of the water,flow velocity,and subbasin size(adjusted R^(2)=0.54).Sample plots clustered in three groups that differed in water chemistry,macroinvertebrate diversity,species composition and bio-indicators.Our study confirms that steppes and grasslands have a higher contribution to runoff than forests,forest cover has a positive impact on water quality,and diversity of macroinvertebrates is higher in sites with less nutrients and pollutants.The excellent ecological status of the upper reaches of the Kharaa is severely threatened by forest fires and human-induced climate change and urgently needs to be conserved.展开更多
Measured and calculated results are presented for the emission properties of a new class of emitters operating in the cavity quantum electrodynamics regime.The structures are based on high-finesse GaAs/AlAs micropilla...Measured and calculated results are presented for the emission properties of a new class of emitters operating in the cavity quantum electrodynamics regime.The structures are based on high-finesse GaAs/AlAs micropillar cavities,each with an active medium consisting of a layer of InGaAs quantum dots(QDs)and the distinguishing feature of having a substantial fraction of spontaneous emission channeled into one cavity mode(highβ-factor).This paper demonstrates that the usual criterion for lasing with a conventional(lowβ-factor)cavity,that is,a sharp non-linearity in the input–output curve accompanied by noticeable linewidth narrowing,has to be reinforced by the equal-time second-order photon autocorrelation function to confirm lasing.The paper also shows that the equal-time second-order photon autocorrelation function is useful for recognizing superradiance,a manifestation of the correlations possible in high-βmicrocavities operating with QDs.In terms of consolidating the collected data and identifying the physics underlying laser action,both theory and experiment suggest a sole dependence on intracavity photon number.Evidence for this assertion comes from all our measured and calculated data on emission coherence and fluctuation,for devices ranging from light-emitting diodes(LEDs)and cavity-enhanced LEDs to lasers,lying on the same two curves:one for linewidth narrowing versus intracavity photon number and the other for g(2)(0)versus intracavity photon number.展开更多
Nanomaterials’properties,influenced by size,shape,and surface characteristics,are crucial for their technological,biological,and environmental applications.Accurate quantification of these materials is essential for ...Nanomaterials’properties,influenced by size,shape,and surface characteristics,are crucial for their technological,biological,and environmental applications.Accurate quantification of these materials is essential for advancing research.Deep learning segmentation networks offer precise,automated analysis,but their effectiveness depends on representative annotated datasets,which are difficult to obtain due to the high cost and manual effort required for imaging and annotation.To address this,we present DiffRenderGAN,a generative model that produces annotated synthetic data by integrating a differentiable renderer into a Generative Adversarial Network(GAN)framework.DiffRenderGAN optimizes rendering parameters to produce realistic,annotated images from non-annotated real microscopy images,reducing manual effort and improving segmentation performance compared to existing methods.Tested on ion and electron microscopy datasets,including titanium dioxide(TiO_(2)),silicon dioxide(SiO_(2)),and silver nanowires(AgNW),DiffRenderGAN bridges the gap between synthetic and real data,advancing the quantification and understanding of complex nanomaterial systems.展开更多
文摘BACKGROUND Primary ciliary dyskinesia(PCD)is a rare genetic disorder caused by motile cilia dysfunction.Identifying pathogenic variants is essential for diagnosis and personalized care,especially in consanguineous populations like Saudi Arabia.CASE SUMMARY This report presents a Saudi pediatric patient diagnosed with PCD who exhibited persistent neonatal tachypnea,chronic productive cough,and recurrent otitis media.Whole-exome sequencing revealed a novel homozygous nonsense variant in the C3orf67 gene(NM_198463.2:c.508C>T),resulting in a truncated,nonfunctional protein.This mutation likely impairs ciliary motility due to the production of a truncated,non-functional protein.The clinical findings were supported by multiple positive sputum cultures and a significant family history of similar symptoms,suggesting a genetic etiology consistent with autosomal recessive inheritance.CONCLUSION This case highlights the importance of genetic studies in diagnosing PCD,particularly in communities with a high rate of consanguinity.The identification of a novel homozygous variant in the C3orf67 gene expands the known genetic landscape of the disease.Further research is essential to clarify the functional role of C3orf67 in ciliary biology and its contribution to PCD pathogenesis.
文摘First-order proximal methods that solve linear and bilinear elliptic optimal control problems with a sparsity cost functional are discussed. In particular, fast convergence of these methods is proved. For benchmarking purposes, inexact proximal schemes are compared to an inexact semismooth Newton method. Results of numerical experiments are presented to demonstrate the computational effectiveness of proximal schemes applied to infinite-dimensional elliptic optimal control problems and to validate the theoretical estimates.
基金supported by the National Natural Science Foudation of China(21473232,21673271,U1710112)
文摘Hierarchical Si C nanowire-supported Pd nanoparticles showed high photocatalytic activity for the C–X(X = Br, I) borylation of aryl halides at 30 °C. The Si C/Pd Mott-Schottky contact enhances the rapid transfer of the photogenerated electrons from Si C to the Pd nanoparticles. As a result, the concentrated energetic electrons in the Pd nanoparticles can facilitate the cleavage of C–I or C–Br bonds, which normally requires high-temperature thermal processes. We show that the present Pd/Si C photocatalyst is capable of catalyzing the transformation of a large variety of aryl halides to their corresponding boronate esters under visible light irradiation, with excellent yields.
文摘An efficient multigrid finite-differences scheme for solving elliptic Fredholm partial integro-differential equations (PIDE) is discussed. This scheme combines a second-order accurate finite difference discretization of the PIDE problem with a multigrid scheme that includes a fast multilevel integration of the Fredholm operator allowing the fast solution of the PIDE problem. Theoretical estimates of second-order accuracy and results of local Fourier analysis of convergence of the proposed multigrid scheme are presented. Results of numerical experiments validate these estimates and demonstrate optimal computational complexity of the proposed framework.
文摘A mathematical optimal-control tumor therapy framework consisting of radio- and anti-angiogenesis control strategies that are included in a tumor growth model is investigated. The governing system, resulting from the combination of two well established models, represents the differential constraint of a non-smooth optimal control problem that aims at reducing the volume of the tumor while keeping the radio- and anti-angiogenesis chemical dosage to a minimum. Existence of optimal solutions is proved and necessary conditions are formulated in terms of the Pontryagin maximum principle. Based on this principle, a so-called sequential quadratic Hamiltonian (SQH) method is discussed and benchmarked with an “interior point optimizer—a mathematical programming language” (IPOPT-AMPL) algorithm. Results of numerical experiments are presented that successfully validate the SQH solution scheme. Further, it is shown how to choose the optimisation weights in order to obtain treatment functions that successfully reduce the tumor volume to zero.
文摘A framework for the optimal sparse-control of the probability density function of a jump-diffusion process is presented. This framework is based on the partial integro-differential Fokker-Planck (FP) equation that governs the time evolution of the probability density function of this process. In the stochastic process and, correspondingly, in the FP model the control function enters as a time-dependent coefficient. The objectives of the control are to minimize a discrete-in-time, resp. continuous-in-time, tracking functionals and its L2- and L1-costs, where the latter is considered to promote control sparsity. An efficient proximal scheme for solving these optimal control problems is considered. Results of numerical experiments are presented to validate the theoretical results and the computational effectiveness of the proposed control framework.
文摘<div style="text-align:justify;"> <span style="font-family:Verdana;">Though many different readability metrics have been created, there still is no universal agreement defining readability of software source code. The lack of a clear agreement of source code readability has ramifications in many areas of the software development life-cycle, not least of which being software maintainability. We propose a measurement based on Linguistic Economy to bridge the gap between mathematical and behavioral aspects. Linguistic Economy describes efficiencies of speech and is generally applied to natural languages. In our study, we create a large corpus of words that are likely to be found in a programmer’s vocabulary, and a corpus of existing identifiers found in a collection of open-source projects. We perform a usage analysis to create a database from both of these corpora. Linguistic Economy suggests that words requiring less effort to speak are used more often than words requiring more effort. This concept is applied to measure how difficult program identifiers are to understand by extracting them from the program source and comparing their usage to the database. Through this process, we can identify source code that programmers find difficult to review. We validate our work using data from a survey where programmers identified unpleasant to review source files. The results indicate that source files identified as unpleasant to review source code have more linguistically complicated identifiers than pleasant programs.</span> </div>
基金funding by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)under DFG DE 1546/12-1(M.D.),559839626(M.D.),and 538291523(S.A.M.S.)funding from Ghent University BOF program grant number BOF23/PDO/073funding enabled and organized by Projekt DEAL.
文摘A remarkable study by Guo et al.,published in Cell,suggests a compelling new direction for improving pain management:biased allosteric modulation of the neurotensin receptor 1(NTSR1),using the drug-like molecule SBI-810,promotesβ-arrestin2(βarr2)recruitment while avoiding canonical G protein signaling–thereby providing robust analgesia across a plethora of rodent models of both acute and chronic pain without impairing motor function,cognition,or causing opioid-like dependency.1,2 SBI-810 is introduced as a highly promising molecule underscoring the therapeutic potential of biased and allosteric G protein-coupled receptor(GPCR)ligands to address an urgent unmet medical need.
基金supported by the State Key Basic Research Project of China(Grant No.2001CB409803)the National Natural Science Foundation of China(Grant No.49972079).
文摘Fluids in the deep subduction zones play an important role in crust-mantle ex-change related to the subduction process. Identification of fluids origin, internal or external, can help us to evaluate the contribution of crust materials to mantle during this process. High-pressure veins, which developed in the western Tianshan HP-metamorphic belt extensively, are the direct products of the fluids in subduction zones. In western Tianshan, high-pressure veins and host rocks have overall Pb- and Sr-isotope compositions. At t = 340 Ma, the high-pressure metamorphic time, the ratios of 206Pb/204Pb, 207Pb/204Pb, 208Pb/204Pb and 87Sr/86Sr of high pressure veins are 17.122―18.431, 15.477―15.611, 37.432―38.689 and 0.70529―0.70705, and are 17.605―17.834, 15.508―15.564, 37.080―38.145 and 0.70522―0.70685 for host rocks. However, high-pressure veins show a much larger variation in Pb-isotope composi-tions than host rocks. Plots of samples are distributed roughly along a line parallel to and far away from the Northern Hemisphere reference line (NHRL) on the plot of 206Pb/204Pb vs 207Pb/204Pb. On the plot of 206Pb/204Pb vs 208Pb/204Pb, plots of data are distributed nearby mid-ocean-ridge basalts (MORB) area or along a line parallel to and not far away from NHRL, which shows that the data plots are farther away from MORB and ocean island basalts (OIB) areas on the plot of 206Pb/204Pb vs 207Pb/204Pb than on the plot of 206Pb/204Pb vs 208Pb/204Pb. The compositions of Pb- and Sr-isotopes of these high-pressure metamorphic rocks are between that of enriched mantle 1(EMI) and of sediments or upper crust. A notable characteristic can be seen from plots of Pb-isotope ratio vs Pb-isotope ratio and 206Pb/204Pb vs 87Sr/86Sr that array of plots shows an evident tendency of mixture of two end members. Ratios of Rb/Ba, Ce/Pb, Nb/U and Ta/U of high-pressure veins and host rocks are between that of OIB or MORB and that of conti-nental crust, which indicates that continental crust materials probably have been incorporated into the rocks. The fluids in the paleosubduction zones in western Tianshan are mixtures of two sources, one originating from the devolatilzation of the host rocks with protolithes similar to ocean basalts from enriched mantle 1 (EMI), the other from the dehydration of subducted sediments.
基金Supported by the Department of Science and Technology, New Delhi (Grant Nos. ESS/023/016/9s and SR/S4/ES-41/2003)he National Geographic Society of USA (Grant No. 3597-87)+1 种基金the Deutsche Orschungsgemeinschaft (Grant No. Fu 131/18-1)DAAD-DST Project-based Personnel Exchange Programme and National Natural Science Foundation of China (Grant No. 40632010)
文摘The Kachchh Basin and the Jaisalmer Basin are two neighboring Mesozoic sedimentary basins at the western margin of the Indian craton. The Jurassic succession of the Kachchh Basin is more complete and more fossiliferous than that of the Jaisalmer Basin. Consequently, intrabasinal correlation of the sedimentary units has been possible in the Kachchh Basin, but not in the Jaisalmer Basin. However, some marker beds existing in the Kachchh Basin can be recognized also in the Jaisalmer Basin. Ammonite evidence shows that they are time-equivalent. The following four units form marker intervals in both basins: (1) the pebbly rudstone unit with Isastrea bernardiana and Leptosphinctes of the Kaladongar Formation (Kachchh Basin) and the Isastrea bernardiana-bearing rudstone of the Jaisalmer Formation (Jaisalmer Basin) both represent transgressive systems tract deposits dated as Late Bajocian; (2) bioturbated micrites with anomalodesmatan bivalves within the Goradongar Yellow Flagstone Member (Kachchh Basin) and bioturbated units in the Fort Member (Jaisalmer Basin) represent maximum flooding zone deposits of the Middle to Late Bathonian; (3) trough-crossbedded, sandy packto grainstones of the Raimalro Limestone Member (Kachchh Basin) and the basal limestone-sandstone unit of the Kuldhar section of the Jaisalmer Formation (Jaisalmer Basin) correspond to Late Bathonain transgressive systems tract deposits; and (4) ferruginous ooid-bearing carbonates with hardgrounds of the Dhosa Oolite member (Kachchh Basin) and the middle part of the Jajiya Member (Jaisalmer Basin) are Oxfordian transgressive systems tract deposits. The fact that in both basins similar biofacies prevailed during certain time intervals demonstrates a common control of their depositional history. As the two basins represent different tectonic settings, the most likely controlling factors were the relative sea-level changes produced by eustatic processes, a common subsidence history of the northwestern margin of the Indian craton, and the paleoclimate.
基金This work has been supported by the EU through the IST project NODE(No.015783)the Marie Curie RTN PARSEM(MRTN-CT-2004-005583).
文摘GaN nanowires have been grown by molecular beam epitaxy either catalyst-free or catalyst-induced by means of Ni seeds.Under identical growth conditions of temperature andⅤ/Ⅲratio,both types of GaN nanowires are of wurtzite structure elongated in the Ga-polar direction and are constricted by M-plane facets.However,the catalyst-induced nanowires contain many more basal-plane stacking faults and their photoluminescence is weaker.These differences can be explained as effects of the catalyst Ni seeds.
基金supported by the German Science Foundation(DFG)within the SPP 1391(MA,TB,WP,BHe and EK)the GSC 266(PT)the ERC Consolidator Grant MULTISCOPE(TB)。
文摘Radiationless energy transfer is at the core of diverse phenomena,such as light harvesting in photosynthesis1,energy-transfer-based microspectroscopies2,nanoscale quantum entanglement3 and photonic-mode hybridization4.Typically,the transfer is efficient only for separations that are much shorter than the diffraction limit.This hampers its application in optical communication and quantum information processing,which require spatially selective addressing.Here,we demonstrate highly efficient radiationless coherent energy transfer over a distance of twice the excitation wavelength by combining localized and delocalized5 plasmonic modes.Analogous to the Tavis–Cummings model,two whispering-gallery-mode antennas6 placed in the foci of an elliptical plasmonic cavity7 fabricated from single-crystal gold plates act as a pair of oscillators coupled to a common cavity mode.Time-resolved two-photon photoemission electron microscopy(TR 2P-PEEM)reveals an ultrafast long-range periodic energy transfer in accordance with the simulations.Our observations open perspectives for the optimization and tailoring of mesoscopic energy transfer and long-range quantum emitter coupling.
基金funded by the German Research Foundation DFG,KU 3384-1/1.
文摘Background:Dispersal is an important event for most organisms at least once in their life cycle.The evolution of dispersal can be infuenced by local adaptation,landscape structure,and perceived temporal and spatial variation.The interaction between local adaptation,landscape heterogeneity,temporal variability and rules of dispersal may be more complex than previously assumed.Therefore,we sought to understand the infuence of emigration rules and landscape structure on emerging dispersal rates and traits.Here,we implemented an individual-based model(IBM)of trait evolution in scenarios characterized by diferent landscape structures and diferent degrees of spatial heterogeneity and global temporal variation.Individuals could evolve two traits coding for their environmental niche(position of niche optimum and niche width),and two traits determining nearest-neighbor dispersal:an individual emigrates with a probability defned by the frst trait(random emigration),but emigrates with certainty if the fertility expected in the patch of residence falls below a threshold specifed by the second trait(habitat-dependent emigration).Results:We note an interaction efect between dispersal strategy and spatial variance—lower emigration under habitat-dependent than under random emigration if spatial heterogeneity is low,but eventually a reversal of this ranking if heterogeneity becomes large.Landscapes with sharp transition of habitat attributes result in a high degree of spatial sorting,while fractal landscapes do not.Emigration rates are overall lowest,when spatial variation is highest.Conclusions:We conclude that emergent emigration rates are infuenced more by landscape structure and spatiotemporal heterogeneity than by the emigration strategy.With the ongoing land use change more research into this topic could help highlight the difculties species might face under the change from landscapes characterized by gradual transition zones to landscapes dominated by abrupt ecotones,the latter typical for agricultural and urban settings.
基金supported by the National Key Research and Development Program of China(No.2022YFB3807200)the Natural Science Foundation of Fujian Province(No.2024J01262)the National Natural Science Foundation of China(No.52201022).
文摘Machine learning(ML)techniques have made enormous progress in the field of materials science.However,many conventional ML algorithms operate as“blackboxes”,lacking transparency in revealing explicit relationships between material features and target properties.To address this,the development of interpretable ML models is essential to drive further advancements in AI-driven materials discovery.In this study,we present an interpretable framework that combines traditional machine learning with symbolic regression,using Janus III–VI vdW heterostructures as a case study.This approach enables fast and accurate predictions of stability and electronic structure.Our results demonstrate that the prediction accuracy using the classification model for stability,based on formation energy,reaches 0.960.On the other hand,the R2,MAE,and RMSE value using the regression model for electronic structure prediction,based on band gap,achieves 0.927,0.113,and 0.141 on the testing set,respectively.Additionally,we identify a universal interpretable descriptor comprising five simple parameters that reveals the underlying physical relationships between the candidate heterostructures and their band gaps.This descriptor not only delivers high accuracy in band gap prediction but also provides explicit physical insight into the material properties.
基金the Israel Science Foundation(ISF)through Grant No.3581/21.
文摘Superconductor-semiconductor hybrid devices can bridge the gap between solid-state-based and photonics-based quantum systems,enabling new hybrid computing schemes,offering increased scalability and robustness.One example for a hybrid device is the superconducting light-emitting diode(SLED).SLEDs have been theoretically shown to emit polarization-entangled photon pairs by utilizing radiative recombination of Cooper pairs.However,the twophoton nature of the emission has not been shown experimentally before.We demonstrate two-photon emission in a GaAs/AlGaAs SLED.Measured electroluminescence spectra reveal unique two-photon superconducting features below the critical temperature(Tc),while temperature-dependent photon-pair correlation experiments(g(2)(τ,T))demonstrate temperature-dependent time coincidences below Tc between photons emitted from the SLED.Our results pave the way for compact and efficient superconducting quantum light sources and open new directions in light-matter interaction studies.
基金funding from the European Research Council(ERC)under the European Union’s Seventh Framework ERC Grant Agreement No.615613the German Research Foundation(DFG)via CRC 787 and Projects No.RE2974/5-1,RE2974/9-1,and SCHN1376/2-1+1 种基金the State of Bavaria,and the German Ministry of Education and Research(BMBF)the support of the DFG through the project B1 of the SFB 910.
文摘Two-level emitters are the main building blocks of photonic quantum technologies and are model systems for the exploration of quantum optics in the solid state.Most interesting is the strict resonant excitation of such emitters to control their occupation coherently and to generate close to ideal quantum light,which is of utmost importance for applications in photonic quantum technology.To date,the approaches and experiments in this field have been performed exclusively using bulky lasers,which hinders the application of resonantly driven two-level emitters in compact photonic quantum systems.Here we address this issue and present a concept for a compact resonantly driven single-photon source by performing quantum-optical spectroscopy of a two-level system using a compact high-βmicrolaser as the excitation source.The two-level system is based on a semiconductor quantum dot(QD),which is excited resonantly by a fiber-coupled electrically driven micropillar laser.We dress the excitonic state of the QD under continuous wave excitation,and trigger the emission of single photons with strong multi-photon suppression(ge2Te0T?0:02)and high photon indistinguishability(V=57±9%)via pulsed resonant excitation at 156 MHz.These results clearly demonstrate the high potential of our resonant excitation scheme,which can pave the way for compact electrically driven quantum light sources with excellent quantum properties to enable the implementation of advanced quantum communication protocols.
基金financially supported by the German Federal Ministry for Economic Cooperation and Development(grant number:BMZ 81212690)and a‘Forschung vor Ort’grant for G.K.of the Max Weber-Program of the State of Bavaria.Special thanks are due to the Deutsche Gesellschaft für Internationale Zusammenarbeit(GIZ)GmbH,especially Klaus Schmidt-Corsitto,at that time Programme Director for“Biodiversity and Adaptation of Key Forest Ecosystems to Climate Change II Program”of GIZ and many employees of GIZ Mongolia.
文摘Headwater streams play a major role for provision of ecosystem services,e.g.drinking water.We investigated a high-altitude headwater catchment of the Kharaa River(including 411st-order rivers)to understand the impact of land cover(especially forest cover),environment and human usage on runoff,chemical water quality and macroinvertebrate fauna in a river basin under discontinuous permafrost conditions in an arid,sparsely populated region of Mongolia.To verify our hypotheses that different landuses and environmental impacts in permafrost headwaters influence water quality,we investigated 105 sampling sites,37 of them at intermittent stream sections without water flow.Discharge was positively impacted by land cover types steppe,grassland and forest and negatively by shrubland,forest burnt by wild fires(indicating a reduction of permafrost)and slope.Water quality was affected by altitude,longitude and latitude,shrub growth and water temperature.Shannon diversity of macroinvertebrates was driven by water temperature,iron content of the water,flow velocity,and subbasin size(adjusted R^(2)=0.54).Sample plots clustered in three groups that differed in water chemistry,macroinvertebrate diversity,species composition and bio-indicators.Our study confirms that steppes and grasslands have a higher contribution to runoff than forests,forest cover has a positive impact on water quality,and diversity of macroinvertebrates is higher in sites with less nutrients and pollutants.The excellent ecological status of the upper reaches of the Kharaa is severely threatened by forest fires and human-induced climate change and urgently needs to be conserved.
基金the European Research Council under the Seventh Framework ERC Grant Agreement No.615613 of the European Unionthe German Research Foundation via the projects RE2974/5-1,Ka23187-1 and JA 619/10-3+3 种基金the US Department of Energy under Contract No.DE-AC04-94AL85000the Technical University Berlin for hospitality and the German Research Foundation via collaborative research center 787 for travel supportsupport from the German Science Foundation(DFG)support from the German Federal Ministry of Education and Research(BMBF).
文摘Measured and calculated results are presented for the emission properties of a new class of emitters operating in the cavity quantum electrodynamics regime.The structures are based on high-finesse GaAs/AlAs micropillar cavities,each with an active medium consisting of a layer of InGaAs quantum dots(QDs)and the distinguishing feature of having a substantial fraction of spontaneous emission channeled into one cavity mode(highβ-factor).This paper demonstrates that the usual criterion for lasing with a conventional(lowβ-factor)cavity,that is,a sharp non-linearity in the input–output curve accompanied by noticeable linewidth narrowing,has to be reinforced by the equal-time second-order photon autocorrelation function to confirm lasing.The paper also shows that the equal-time second-order photon autocorrelation function is useful for recognizing superradiance,a manifestation of the correlations possible in high-βmicrocavities operating with QDs.In terms of consolidating the collected data and identifying the physics underlying laser action,both theory and experiment suggest a sole dependence on intracavity photon number.Evidence for this assertion comes from all our measured and calculated data on emission coherence and fluctuation,for devices ranging from light-emitting diodes(LEDs)and cavity-enhanced LEDs to lasers,lying on the same two curves:one for linewidth narrowing versus intracavity photon number and the other for g(2)(0)versus intracavity photon number.
基金supported by the European Union’s H2020 research and innovation program under the Marie Sklodowska-Curie grant agreement AIMed ID:861138D.P.,D.A.,G.S.and S.C.acknowledge the financial support from the European Union within the research projects 4D+nanoSCOPE ID:810316,LRI ID:C10,STOP ID:101057961+1 种基金from the German Research Foundation(DFG)within the research project UNPLOK ID:523847126,and from the“Freistaat Bayern”European Union within the project Analytiktechnikum für Gesundheits-und Umweltforschung AGEUM,StMWi-43-6623-22/1/3.
文摘Nanomaterials’properties,influenced by size,shape,and surface characteristics,are crucial for their technological,biological,and environmental applications.Accurate quantification of these materials is essential for advancing research.Deep learning segmentation networks offer precise,automated analysis,but their effectiveness depends on representative annotated datasets,which are difficult to obtain due to the high cost and manual effort required for imaging and annotation.To address this,we present DiffRenderGAN,a generative model that produces annotated synthetic data by integrating a differentiable renderer into a Generative Adversarial Network(GAN)framework.DiffRenderGAN optimizes rendering parameters to produce realistic,annotated images from non-annotated real microscopy images,reducing manual effort and improving segmentation performance compared to existing methods.Tested on ion and electron microscopy datasets,including titanium dioxide(TiO_(2)),silicon dioxide(SiO_(2)),and silver nanowires(AgNW),DiffRenderGAN bridges the gap between synthetic and real data,advancing the quantification and understanding of complex nanomaterial systems.
