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1.
ACS Nano ; 18(16): 10930-10945, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38604994

RESUMEN

Rechargeable alkali metal-CO2 batteries, which combine high theoretical energy density and environmentally friendly CO2 fixation ability, have attracted worldwide attention. Unfortunately, their electrochemical performances are usually inferior for practical applications. Aiming to reveal the underlying causes, a combinatorial usage of advanced nondestructive and postmortem characterization tools is used to intensively study the failure mechanisms of Li/Na-CO2 batteries. It is found that a porous interphase layer is formed between the separator and the Li/Na anode during the overvoltage rising and battery performance decaying process. A series of control experiments are designed to identify the underlying mechanisms dictating the observed morphological evolution of Li/Na anodes, and it is found that the CO2 synergist facilitates Li/Na chemical corrosion, the process of which is further promoted by the unwanted galvanic corrosion and the electrochemical cycling conditions. A detailed compositional analysis reveals that the as-formed interphase layers under different conditions are similar in species, with the main differences being their inconsistent quantity. Theoretical calculation results not only suggest an inherent intermolecular affinity between the CO2 and the electrolyte solvent but also provide the most thermodynamically favored CO2 reaction pathways. Based on these results, important implications for the further development of rechargeable alkali metal-CO2 batteries are discussed. The current discoveries not only fundamentally enrich our knowledge of the failure mechanisms of rechargeable alkali metal-CO2 batteries but also provide mechanistic directions for protecting metal anodes to build high-reversible alkali metal-CO2 batteries.

2.
J Alzheimers Dis ; 93(3): 891-906, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37125549

RESUMEN

BACKGROUND: Information technology can enhance timely and individual support for people with Alzheimer's disease and other dementias and their informal carers. OBJECTIVE: To review the effectiveness of technology-based counselling interventions for people with dementia and informal carers. METHODS: Randomized controlled trials of remote dementia counselling interventions were included. We searched CINAHL, Cochrane Library, MEDLINE, PsycINFO, and the Web of Science Core Collection (April 2021) in combination with citation tracking and free web searching (October to November 2021). We provide meta-analyses for caregiver depression, burden, and self-efficacy/mastery and structured reporting for other outcomes. The Grading of Recommendations Assessment, Development and Evaluation approach and the Risk of Bias 2 tool were applied. RESULTS: We included five randomized controlled trials involving 880 participants. Interventions were provided for carers (four studies) or dyads (one study). Carers were predominantly women and were the spouses or children of people with dementia. Counselling was delivered via telephone or videoconference with two to 23 sessions over 1 to 12 months. Control groups received educational and resource materials only, standard (helpline) services, non-directive support, or home visits. Meta-analysis for our primary outcome, depressive symptoms in carers, revealed no statistically significant effect (SMD -0.15; 95% CI -0.40 to 0.10). There were also no significant effects on burden and self-efficacy/mastery. We rated the certainty of evidence as low to very low and all outcomes at an overall high risk of bias. CONCLUSION: The effectiveness of technology-based counselling interventions for people with dementia and informal carers remains uncertain. Theory-based approaches are needed for the development and evaluation of these interventions.


Asunto(s)
Enfermedad de Alzheimer , Cuidadores , Humanos , Femenino , Masculino , Autoeficacia , Consejo , Tecnología , Calidad de Vida
3.
Sci Bull (Beijing) ; 68(8): 813-825, 2023 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-36967270

RESUMEN

An in-depth understanding of the degradation mechanisms is a prerequisite for developing the next-generation all solid-state lithium metal battery (ASSLMB) technology. Herein, synchrotron X-ray computed tomography (SXCT) together with other probing tools and simulation method were employed to rediscover the decaying mechanisms of LiNi0.8Co0.1Mn0.1O2 (NCM)|Li6PS5Cl (LPSCl)|Li ASSLMB. It reveals that the detachment and isolation of NCM particles cause the current focusing on the remaining active regions of cathode. The extent of Li stripping and the likelihood of Li+ plating into LPSCl facing the active NCM particles becomes higher. Besides, the homogeneity of Li stripping/plating is improved by homogenizing the electrochemical reactions at the cathode side by LiZr2(PO4)3 (LZP) coating. These results suggest a codependent failure mechanism between cathode and anode that is mediated by uneven Li ion flux. This work contributes to a holistic understanding of the degradation mechanisms in ASSLMBs and opens new opportunities for their further optimization and development.

4.
Bioresour Technol ; 373: 128713, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36758644

RESUMEN

This study pioneers the feasibility of cost-effective partial nitritation/anammox (PN/A) in packed-bed trickling filters (TFs). Three parallel TFs tested different carrier materials, the presence or absence of bottom ventilation openings, hydraulic loading rates (HLR, 0.4-2.2 m3 m-2 h-1), and free ammonia (FA) levels on synthetic medium. The inexpensive Argex expanded clay was recommended due to the similar nitrogen removal rates as commercially used plastics. Top-only ventilation at an optimum HLR of 1.8 m3 m-2 h-1 could remove approximately 60% of the total nitrogen load (i.e., 300 mg N L-1 d-1, 30 °C) and achieve relatively low NO3--N accumulation (13%). Likely FA levels of around 1.3-3.2 mg N L-1 suppressed nitratation. Most of the total nitrogen removal took place in the upper third of the reactor, where anammox activity was highest. Provided further optimizations, the results demonstrated TFs are suitable for low-energy shortcut nitrogen removal.


Asunto(s)
Amoníaco , Compuestos de Amonio , Oxidación Anaeróbica del Amoníaco , Estudios de Factibilidad , Reactores Biológicos , Nitrógeno , Oxidación-Reducción
5.
Med Phys ; 50(3): 1601-1613, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36309985

RESUMEN

BACKGROUND: The formation of concrements in human pineal gland (PG) is a physiological process and, according to many researchers, is associated with the involution of PG structures. The majority of scientific publications concern progressive calcification of PG, leaving out studies on the destruction of already formed calcified concrements. Our study fills the gap in knowledge about calcified zones destruction in PG in normal aging and neuropathological conditions, which has not been addressed until now. PURPOSE: Our objective is to gain insight into human PG tissue impairment in both normal aging and neurodegenerative conditions. X-ray phase-contrast tomography (XPCT) allowed us to study PG tissue degeneration at high spatial resolution and, for the first time, to examine the damaged PG concrements in detail. Our research finding could potentially enhance the understanding of the PG involvement in the process of aging as well as in Alzheimer's disease (AD) and vascular dementia (VD). METHODS: The research was carried out on human PG autopsy material in normal aging, VD, and AD conditions. Laboratory-based micro-computed tomography (micro-CT) was used to collect and evaluate samples of native, uncut, and unstained PG with different degrees of pineal calcification. The detailed high-resolution 3D images of the selected PGs were produced using synchrotron-based XPCT. Histology and immunohistochemistry of soft PG tissue confirmed XPCT results. RESULTS: We performed via micro-CT the evaluation of the morphometric parameters of PG such as total sample volume, calcified concrements volume, and percentage of concrements in the total volume of the sample. XPCT imaging revealed high-resolution details of age-related PG alteration. In particular, we noted signs of moderate degradation of concrements in some PGs from elderly donors. In addition, our analysis revealed noticeable degenerative change in both concrements and soft tissue of PGs with neuropathology. In particular, we observed a hollow core and separated layers as well as deep ragged cracks in PG concrements of AD and VD samples. In parenchyma of some samples, we detected wide pinealocyte-free fluid-filled areas adjacent to the calcified zones. CONCLUSION: The present work provides the basis for future scientific research focused on the dynamic nature of PG calcium deposits and PG soft tissue in normal aging and neurodegenerative diseases.


Asunto(s)
Enfermedad de Alzheimer , Calcinosis , Enfermedades Neurodegenerativas , Glándula Pineal , Humanos , Anciano , Glándula Pineal/diagnóstico por imagen , Glándula Pineal/metabolismo , Glándula Pineal/patología , Microtomografía por Rayos X , Enfermedades Neurodegenerativas/diagnóstico por imagen , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/patología , Calcinosis/diagnóstico por imagen , Calcinosis/patología
6.
Tomography ; 8(4): 1854-1868, 2022 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-35894021

RESUMEN

The human olfactory bulb (OB) has a laminar structure. The segregation of cell populations in the OB image poses a significant challenge because of indistinct boundaries of the layers. Standard 3D visualization tools usually have a low resolution and cannot provide the high accuracy required for morphometric analysis. X-ray phase contrast tomography (XPCT) offers sufficient resolution and contrast to identify single cells in large volumes of the brain. The numerous microanatomical structures detectable in XPCT image of the OB, however, greatly complicate the manual delineation of OB neuronal cell layers. To address the challenging problem of fully automated segmentation of XPCT images of human OB morphological layers, we propose a new pipeline for tomographic data processing. Convolutional neural networks (CNN) were used to segment XPCT image of native unstained human OB. Virtual segmentation of the whole OB and an accurate delineation of each layer in a healthy non-demented OB is mandatory as the first step for assessing OB morphological changes in smell impairment research. In this framework, we proposed an effective tool that could help to shed light on OB layer-specific degeneration in patients with olfactory disorder.


Asunto(s)
Aprendizaje Profundo , Bulbo Olfatorio , Humanos , Redes Neurales de la Computación , Bulbo Olfatorio/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Rayos X
7.
Cells ; 12(1)2022 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-36611969

RESUMEN

BACKGROUND: High-dose-rate radiotherapy has shown promising results with respect to normal tissue preservation. We developed an ex vivo model to study the physiological effects of experimental radiotherapy in the rodent esophageal smooth muscle. METHODS: We assessed the physiological parameters of the esophageal function in ex vivo preparations of the proximal, middle, and distal segments in the organ bath. High-dose-rate synchrotron irradiation was conducted using both the microbeam irradiation (MBI) technique with peak doses greater than 200 Gy and broadbeam irradiation (BBI) with doses ranging between 3.5-4 Gy. RESULTS: Neither MBI nor BBI affected the function of the contractile apparatus. While peak latency and maximal force change were not affected in the BBI group, and no changes were seen in the proximal esophagus segments after MBI, a significant increase in peak latency and a decrease in maximal force change was observed in the middle and distal esophageal segments. CONCLUSION: No severe changes in physiological parameters of esophageal contraction were determined after high-dose-rate radiotherapy in our model, but our results indicate a delayed esophageal function. From the clinical perspective, the observed increase in peak latency and decreased maximal force change may indicate delayed esophageal transit.


Asunto(s)
Esófago , Roedores , Animales , Contracción Muscular/fisiología , Músculo Liso
8.
BMJ Open ; 11(12): e054157, 2021 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-34880025

RESUMEN

INTRODUCTION: Information technology can enhance timely and individual support for people with dementia and informal carers. There is some evidence that people with dementia and informal carers would benefit from technology-based counselling. However, it remains unclear which features of those interventions relate to beneficial outcomes and which aspects are necessary for a successful implementation. Therefore, the primary objectives are: (1) to identify conditions of successful implementation of technology-based counselling interventions in dementia and (2) to investigate the effectiveness of those interventions. METHODS AND ANALYSIS: We will conduct a mixed-methods systematic review. The first primary objective requires evidence from various study designs addressing aspects on effective and non-effective implementation of technology-based counselling. This could be telephone-based, web-based or mobile-based interventions for people with dementia and informal carers. For the second primary objective, randomised controlled trials (RCTs) dealing with any outcomes will be included. Year of publication and language will not be restricted. We will search CINAHL, Cochrane Library, MEDLINE, PsycINFO and Web of Science up to April 2021. Additionally, we will perform web searching and citation tracking. To achieve the first primary objective, a Qualitative Comparative Analysis (QCA) will be conducted. The QCA enables us to identify necessary or sufficient components for a successful implementation. To reach the second primary objective, a meta-analysis will be performed with respect to potential clinical and statistical heterogeneity of RCTs. The revised Risk of Bias tool 2.0 will be used to check the risk of bias in RCTs. For all other study designs, the Mixed Method Appraisal Tool will be used. ETHICS AND DISSEMINATION: Ethics approval is not required for this review. We will disseminate our findings through scientific and non-scientific journal articles and conference presentations as well as formats directed to the public and decision-makers in healthcare. PROSPERO REGISTRATION NUMBER: CRD42021245473.


Asunto(s)
Cuidadores , Demencia , Consejo , Demencia/terapia , Humanos , Metaanálisis como Asunto , Literatura de Revisión como Asunto , Tecnología , Teléfono
9.
Proc Biol Sci ; 288(1953): 20210616, 2021 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-34130499

RESUMEN

Most animals undergo ecological niche shifts between distinct life phases, but such shifts can result in adaptive conflicts of phenotypic traits. Metamorphosis can reduce these conflicts by breaking up trait correlations, allowing each life phase to independently adapt to its ecological niche. This process is called adaptive decoupling. It is, however, yet unknown to what extent adaptive decoupling is realized on a macroevolutionary scale in hemimetabolous insects and if the degree of adaptive decoupling is correlated with the strength of ontogenetic niche shifts. It is also unclear whether the degree of adaptive decoupling is correlated with phenotypic disparity. Here, we quantify nymphal and adult trait correlations in 219 species across the whole phylogeny of earwigs and stoneflies to test whether juvenile and adult traits are decoupled from each other. We demonstrate that adult head morphology is largely driven by nymphal ecology, and that adult head shape disparity has increased with stronger ontogenetic niche shifts in some stonefly lineages. Our findings implicate that the hemimetabolan metamorphosis in earwigs and stoneflies does not allow for high degrees of adaptive decoupling, and that high phenotypic disparity can even be realized when the evolution of distinct life phases is coupled.


Asunto(s)
Evolución Biológica , Insectos , Animales , Ecología , Metamorfosis Biológica , Filogenia
10.
Insects ; 12(4)2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33923404

RESUMEN

Lebambromyia sacculifera sp. nov. is described from Late Cretaceous amber from Myanmar, integrating traditional observation techniques and X-ray phase contrast microtomography. Lebambromyia sacculifera is the second species of Lebambromyia after L. acrai Grimaldi and Cumming, described from Lebanese amber (Early Cretaceous), and the first record of this taxon from Myanmar amber, considerably extending the temporal and geographic range of this genus. The new specimen bears a previously undetected set of phylogenetically relevant characters such as a postpedicel sacculus and a prominent clypeus, which are shared with Ironomyiidae and Eumuscomorpha. Our cladistic analyses confirmed that Lebambromyia represented a distinct monophyletic lineage related to Platypezidae and Ironomyiidae, though its affinities are strongly influenced by the interpretation and coding of the enigmatic set of features characterizing these fossil flies.

11.
J Exp Biol ; 224(Pt 2)2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33443040

RESUMEN

The velocity of settling particles is an important determinant of distribution in extinct and extant species with passive dispersal mechanisms, such as plants, corals and phytoplankton. Here, we adapted dynamic scaling, borrowed from engineering, to determine settling velocity. Dynamic scaling leverages physical models with relevant dimensionless numbers matched to achieve similar dynamics to the original object. Previous studies have used flumes, wind tunnels or towed models to examine fluid flow around objects with known velocities. Our novel application uses free-falling models to determine the unknown sinking velocity of planktonic Foraminifera - organisms important to our understanding of the Earth's current and historic climate. Using enlarged 3D printed models of microscopic Foraminifera tests, sunk in viscous mineral oil to match their Reynolds numbers and drag coefficients, we predicted sinking velocity of real tests in seawater. This method can be applied to study other settling particles such as plankton, spores or seeds.


Asunto(s)
Foraminíferos , Accidentes por Caídas , Clima , Modelos Teóricos , Agua de Mar
12.
Nat Commun ; 11(1): 657, 2020 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-32005876

RESUMEN

To advance microfluidic integration, we present the use of two-photon additive manufacturing to fold 2D channel layouts into compact free-form 3D fluidic circuits with nanometer precision. We demonstrate this technique by tailoring microfluidic nozzles and mixers for time-resolved structural biology at X-ray free-electron lasers (XFELs). We achieve submicron jets with speeds exceeding 160 m s-1, which allows for the use of megahertz XFEL repetition rates. By integrating an additional orifice, we implement a low consumption flow-focusing nozzle, which is validated by solving a hemoglobin structure. Also, aberration-free in operando X-ray microtomography is introduced to study efficient equivolumetric millisecond mixing in channels with 3D features integrated into the nozzle. Such devices can be printed in minutes by locally adjusting print resolution during fabrication. This technology has the potential to permit ultracompact devices and performance improvements through 3D flow optimization in all fields of microfluidic engineering.


Asunto(s)
Microfluídica/instrumentación , Impresión Tridimensional/instrumentación , Biología Sintética/instrumentación , Hemo/química , Hemoglobinas/química , Humanos , Rayos Láser , Microfluídica/métodos , Biología Sintética/métodos , Microtomografía por Rayos X
13.
Acta Biomater ; 104: 28-38, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31923720

RESUMEN

Durophagous fish consume a diet based primarily on hard-shelled animals, mainly mollusks. In order to successfully perform this task, they are equipped with an extra set of jaws located in their throat called pharyngeal jaws. Here we present the results of a study of the structure of the bony material of the exceptionally powerful lower pharyngeal jaws (LPJs) of the black drum Pogonias cromis which generate the highest biting forces documented in bony fishes. In particular, we studied the two long and slender struts that support the entire dental plate and teeth of the LPJ, in order to determine how this structure withstands the huge stresses it encounters repetitively and for long periods of time. We describe the hierarchical structure of the struts of lower pharyngeal jaw of P. cromis at a wide range of length scales, and show how it is adapted to successfully achieve its high mechanical performance. In particular, we show that the bone material of the strut is neither cortical nor cancellous, and although it is highly porous, its complex and layered three-dimensional arrangement of thick lamellae sheets, which are inter-connected by thin plates, is perfectly tailored to withstand extremely large but directionally-consistent forces. STATEMENT OF SIGNIFICANCE: The diet of some fish consists of hard food, like mollusks and shells. In order to accomplish the task of cracking this type of food, they have an extra set of bony jaws located in their throat, called pharyngeal jaws. Here we describe the hierarchical structural elements of these jaws which allow them to withstand huge forces repeatedly over long periods of time. Surprisingly, the structure is very porous, but its architectural design is superbly adapted to handle consistently-oriented forces. This structural motif defines a new bony material which is neither cortical nor cancellous.


Asunto(s)
Hueso Esponjoso/fisiología , Hueso Cortical/fisiología , Peces/fisiología , Maxilares/fisiología , Faringe/fisiología , Animales , Hueso Esponjoso/diagnóstico por imagen , Hueso Cortical/diagnóstico por imagen , Análisis de Elementos Finitos , Imagenología Tridimensional , Maxilares/diagnóstico por imagen , Faringe/diagnóstico por imagen , Soporte de Peso , Microtomografía por Rayos X
14.
Sci Rep ; 9(1): 19611, 2019 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-31873105

RESUMEN

Human-based segmentation of tomographic images can be a tedious time-consuming task. Deep learning algorithms and, particularly, convolutional neural networks have become state of the art techniques for pattern recognition in digital images that can replace human-based image segmentation. However, their use in materials science is beginning to be explored and their application needs to be adapted to the specific needs of this field. In the present work, a convolutional neural network is trained to segment the microstructural components of an Al-Si cast alloy imaged using synchrotron X-ray tomography. A pixel-wise weighted error function is implemented to account for microstructural features which are hard to identify in the tomographs and that play a relevant role for the correct description of the 3D architecture of the alloy investigated. The results show that the total operation time for the segmentation using the trained convolutional neural network was reduced to <1% of the time needed with human-based segmentation.

16.
Rev Sci Instrum ; 90(4): 043502, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31042980

RESUMEN

This paper reports about a novel approach to the absolute intensity calibration of an electron cyclotron emission (ECE) spectroscopy system. Typically, an ECE radiometer consists of tens of separated frequency channels corresponding to different plasma locations. An absolute calibration of the overall diagnostic including near plasma optics and transmission line is achieved with blackbody sources at LN2 temperature and room temperature via a hot/cold calibration mirror unit. As the thermal emission of the calibration source is typically a few thousand times lower than the receiver noise temperature, coherent averaging over several hours is required to get a sufficient signal to noise ratio. A forward model suitable for any radiometer calibration using the hot/cold method and a periodic switch between them has been developed and used to extract the voltage difference between the hot and cold temperature source via Bayesian analysis. In contrast to the classical analysis which evaluates only the reference temperatures, the forward model takes into account intermediate effective temperatures caused by the finite beam width and thus uses all available data optimally. This allows the evaluation of weak channels where a classical analysis would not be feasible, is statistically rigorous, and provides a measurement of the beam width. By using a variance scaling factor, a model sensitive adaptation of the absolute uncertainties can be implemented, which will be used for the combined diagnostic Bayesian modeling analysis.

17.
J Synchrotron Radiat ; 26(Pt 1): 194-204, 2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30655485

RESUMEN

Full-field transmission X-ray microscopy (TXM) is a well established technique, available at various synchrotron beamlines around the world as well as by laboratory benchtop devices. One of the major TXM challenges, due to its nanometre-scale resolution, is the overall instrument stability during the acquisition of the series of tomographic projections. The ability to correct for vertical and horizontal distortions of each projection image during acquisition is necessary in order to achieve the effective 3D spatial resolution. The effectiveness of such an image alignment is also heavily influenced by the absorption properties and strong contrast of specific features in the scanned sample. Here it is shown that nanoporous gold (NPG) can be used as an ideal 3D test pattern for evaluating and optimizing the performance of a TXM instrument for hard X-rays at a synchrotron beamline. Unique features of NPG, such as hierarchical structures at multiple length scales and high absorbing capabilities, makes it an ideal choice for characterization, which involves a combination of a rapid-alignment algorithm applied on the acquired projections followed by the extraction of a set of both 2D- and 3D-descriptive image parameters. This protocol can be used for comparing the efficiency of TXM instruments at different synchrotron beamlines in the world or benchtop devices, based on a reference library of scanned NPG samples, containing information about the estimated horizontal and vertical alignment values, 2D qualitative parameters and quantitative 3D parameters. The possibility to tailor the ligament sizes of NPG to match the achievable resolution in combination with the high electron density of gold makes NPG an ideal 3D test pattern for evaluating the status and performance of a given synchrotron-based or benchtop-based TXM setup.

19.
Sci Rep ; 7: 44628, 2017 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-28300169

RESUMEN

Serial femtosecond crystallography requires reliable and efficient delivery of fresh crystals across the beam of an X-ray free-electron laser over the course of an experiment. We introduce a double-flow focusing nozzle to meet this challenge, with significantly reduced sample consumption, while improving jet stability over previous generations of nozzles. We demonstrate its use to determine the first room-temperature structure of RNA polymerase II at high resolution, revealing new structural details. Moreover, the double-flow focusing nozzles were successfully tested with three other protein samples and the first room temperature structure of an extradiol ring-cleaving dioxygenase was solved by utilizing the improved operation and characteristics of these devices [corrected].


Asunto(s)
Cristalografía/instrumentación , Reología/instrumentación , Simulación por Computador , ARN Polimerasa II/química , Saccharomyces cerevisiae/enzimología , Temperatura , Factores de Tiempo , Difracción de Rayos X
20.
Opt Express ; 24(11): 11515-30, 2016 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-27410079

RESUMEN

Reliable sample delivery is essential to biological imaging using X-ray Free Electron Lasers (XFELs). Continuous injection using the Gas Dynamic Virtual Nozzle (GDVN) has proven valuable, particularly for time-resolved studies. However, many important aspects of GDVN functionality have yet to be thoroughly understood and/or refined due to fabrication limitations. We report the application of 2-photon polymerization as a form of high-resolution 3D printing to fabricate high-fidelity GDVNs with submicron resolution. This technique allows rapid prototyping of a wide range of different types of nozzles from standard CAD drawings and optimization of crucial dimensions for optimal performance. Three nozzles were tested with pure water to determine general nozzle performance and reproducibility, with nearly reproducible off-axis jetting being the result. X-ray tomography and index matching were successfully used to evaluate the interior nozzle structures and identify the cause of off-axis jetting. Subsequent refinements to fabrication resulted in straight jetting. A performance test of printed nozzles at an XFEL provided high quality femtosecond diffraction patterns.

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