Axial Dimensions Research Articles

Distinct Ventral Hippocampus Network Properties inDissociated Cultures.

Extensive research has been focused in the past century on structural, physiological, and molecular attributes of the hippocampus. This interest was created by the unique involvement of the hippocampus in cognitive and affective functions of the brain. Functional analysis revealed that the hippocampus has divergent properties along its axial dimension to the extent that the dorsal sector (dorsal hippocampus, DH) has different connections with the rest of the brain than those of the ventral sector (VH). Still, longitudinal pathways connect the DH with the VH and dampen the functional differences between the sectors. To be able to identify the intrinsic functional difference between the DH and VH, we produced dissociated monolayer cultures from prenatal DH and VH and examined their properties at 10-20 days after plating by imaging the spontaneous activity of the network using Fluo-2 AM, a calcium indicator. Surprisingly, while DH and VH sectors produced dissociated cultures with similar morphological attributes, VH cultures were more active spontaneously than DH cultures. Furthermore, when stimulated to produce action potentials, VH neurons triggered network bursts in postsynaptic neurons more often than DH cultures. Finally, in both DH and VH cultures, electrical stimulation of single cells produced network bursts in response to a burst of action potentials rather than to single spikes. These experiments indicate that even in dissociated cultures, neurons of the VH are more excitable and sensitive to electrical stimulation than DH; hence, they are more likely to generate network bursts and epileptic seizures, as suggested for invivo brains.

Numerical studies on structure optimization and flow characteristics of a hydrogen recirculation ejector under multiple load conditions

Ejectors are ideal hydrogen recirculation devices for PEMFC systems but typically exhibit poor recirculation performance at low loads. For purpose of extending ejector's operating range in vehicular applications, the entraining performance across multiple loads should be focused. In this study, A 40 kW ejector was designed with a 1D theory and optimized using a 2D CFD model. Simulations were conducted to study the influence of various diameter and axial dimensions on the ejector's performance and flow characteristics. The results reveal that as the load increases from 20% to 100%, the suboptimal diffuser exit diameter decreases from 2.5 to 1.5 times the mixing chamber diameter, the optimal nozzle exit position increases from 0.59 to 0.63 times, and the optimal mixing chamber length increases from 2.2 to 4.3 times. A convergent nozzle with a short throat significantly improves low-load entraining performance and achieves the highest performance growth in the variable-nozzle design. Additionally, an optimization method for axial dimensions based on the proposed parameter flow uniformity was established, allowing for precise determination of the optimal dimensions through a few simulations.

Research on Ultrasonic Guided Wave Pipeline Defect Detection Method Based on Modal Analysis

Abstract Pipelines are important transmission media in the petroleum industry, and their safe and stable operation is of great significance to industrial safety. The secure and reliable operation of oil and gas pipelines holds paramount importance for industrial safety. The significance of non-destructive testing (NDT) technology in this context is steadily growing. Presently, guided wave-based pipeline defect detection technology has garnered considerable attention. This method is noteworthy for its extensive coverage, ability to inspect the entire cross-section, and its capability to conduct inspections without disrupting ongoing production processes. Research focused on the displacement distribution of various modes of guided waves, exploring different excitation methods for each mode. The investigation also delved into the interaction mechanism between guided waves and pipeline defects; Conducted research on the detection of axial, circumferential and radial dimensions of defects using different modes of guided waves, and carried out experimental verification, studying the transformation law of the reflection coefficient of the defect reflection echo when the flaw size changes provide a reference for pipeline defect detection based on guided waves.

Towards the Automation of Non-destructive Fault Recognition: Enhancement of Robustness and Accuracy Through AI Powered Acoustic and Thermal Signal Analysis in Time, Frequency- and Time-Frequency Domains

AbstractNon-destructive inspection and analysis techniques are crucial for quality assessment and defect analysis in various industries. They enable for screening and monitoring of parts and products without alteration or impact, facilitating the exploration of material interactions and defect formation. With increasing complexity in microelectronic technologies, high reliability, robustness and thus, successful failure analysis is essential. Machine learning (ML) approaches have been developed and evaluated for the analysis of acoustic echo signals and time-resolved thermal responses for assessing their ability for defect detection. In the present paper different ML architectures were evaluated, including 1D and 2D convolutional neural networks (CNNs) after transforming time domain data into the spectral- and wavelet domains. Results showed that 2D CNNs processing data in wavelet domain representation performed best, however at the expense of additional computational effort. Furthermore, ML-based analysis was explored for lock-in thermography to detect and locate defects in the axial dimension based on thermal emissions. While promising, further research is needed to fully realize its potential.

A-scan fluorescence microscopy for rapid cross-sectional imaging

This paper presents a microscopy technique that can perform snapshot depth resolved optical imaging in the same manner as A-scan in ultrasound imaging and optical coherence tomography. In this technique, a laser line along the axial dimension is used to illuminate a sample to create a fluorescent line object. By transforming the line object along the axial dimension (Z) to a ring image on the lateral dimensions (X-Y) using a full cone mirror, common optics can be used to relay and acquire the ring image precisely. Then, by converting half of the ring image back to a line image using a half cone mirror, the opening side of the half cone mirror allows the line image, which contains the full depth resolved information of the line object, to be taken in one snapshot. This eliminates the requirement of axial scanning in traditional depth resolved imaging techniques such as confocal microscopy to obtain the same information. The technique is demonstrated by imaging fluorescent microspheres of different diameters. This technique offers a simple alternative to traditional depth resolved imaging techniques such as confocal microscopy and light sheet microscopy. It is particularly useful in imaging samples with multiple layers in which multiple A-scans or a few B-scans are sufficient to represent the entire sample.

Modeling of sediment transport direction affecting Failaka island marina bathymetry, Kuwait

Failaka Island has a marina, which was constructed in 1979 and managed by the Ministry of Communication (MOC) in collaboration with Touristic Enterprises Company (TEC). The marina is widely used for its ferry landing facility. The coastal waters around Failaka are turbid, and current velocities tend to be as high as ∼0.5 m/s during spring tide. The marina basin, with axial plane view and dimensions of about 285m by 260m, experiences shoaling of naturally flocculated fine (cohesive) sediment and coarse sand at the entrance of the channel and more generally in the southern half of the basin. Particularly noteworthy is its heavy shoaling zone along the inner side of the south breakwater close to the entrance. The Failaka island marina is suffering from siltation and sediment deposition issues. The study was carried out numerically to assess the annual sedimentation, sediment direction, and longshore current from different locations around the marina and recommend solutions to reduce the siltation and sediment deposition based on sediment transport direction at the marina entrance. The study shows that the sediment is mostly transported to the Failaka marina entrance from the southeast due to wave action. The cumulative sediment transport for the period 2016 to 2020 as depicted from locations 1 and 2, which are vulnerable to the southeast waves, is 9,164 m3 and 12,323 m3. The annual sediment transport direction affecting the marina is oriented from south to north due to wave action.

Improved air gap permeance modelling for single-slice magnetic equivalent circuits of skewed induction motors

PurposeWhen rotor and stator teeth are close, the connecting air gap flux tube's cross-sectional area exceeds the tooth overlap area. This flux fringing effect is disregarded in the air gap permeance calculation of single-slice magnetic equivalent circuits (MECs) of electric motors with skewed rotors. This paper aims to extend an air gap permeance calculation method incorporating flux fringing for unskewed rotors to skewed and radially eccentric rotors.Design/methodology/approachAssuming axial independence, the unskewed air gap permeance is rotated according to the skew and integrated along the axial dimension, resulting in a first method. The integral is approximated analytically, resulting in a second method. Results are compared to a commonly used reference method and validated using a non-linear finite element method (FEM) simulation.FindingsThe proposed methods provide better alignment with the FEM validation compared to the reference method for skewed rotors and common rotor eccentricity, i.e. below 50% of the air gap length. The analytical method is shown to be competitive with the reference method regarding computational time cost.Originality/valueTwo novel air gap permeance methods are proposed for single-slice MECs with skewed rotors. Their characteristics are discussed and validated.

Dimensional crossover of microscopic magnetic metasurfaces for magnetic field amplification

Transformation optics applied to low frequency magnetic systems have been recently implemented to design magnetic field concentrators and cloaks with superior performance. Although this achievement has been amply demonstrated theoretically and experimentally in bulk 3D macrostructures, the performance of these devices at low dimensions remains an open question. In this work, we numerically investigate the non-monotonic evolution of the gain of a magnetic metamaterial field concentrator as the axial dimension is progressively shrunk. In particular, we show that in planar structures, the role played by the diamagnetic components becomes negligible, whereas the paramagnetic elements increase their magnetic field channeling efficiency. This is further demonstrated experimentally by tracking the gain of superconductor-ferromagnet concentrators through the superconducting transition. Interestingly, for thicknesses where the diamagnetic petals play an important role in the concentration gain, they also help to reduce the stray field of the concentrator, thus limiting the perturbation of the external field (invisibility). Our findings establish a roadmap and set clear geometrical limits for designing low dimensional magnetic field concentrators.

Moisture‐modulated thermo‐physical analysis of sweetsop seed (Annona squamosa L.): A potential biofuel feedstock plant

AbstractSweetsop seed holds significant economic value as an oil seed, with ca. 25% oil content that finds applications as a feedstock for energy generation. The moisture‐modulated thermophysical properties of the seed were determined at varying moisture contents (8.0%–32.5%). Physical properties (length [L], width [W], thickness [T], arithmetic [Amd], and geometric mean diameters [Gmd], sphericity [Sty], surface area [SA], and bulk density [ρd]) were determined using standard methods while the thermal properties (specific heat capacity [SHC], thermal conductivity [Tcd], and thermal diffusivity [Tdf]) were analyzed using a TEMPOS thermal analyzer. The results showed that the seed L, W, T, Amd, and Gmd, Sty, SA, and ρd ranged from 13.22–14.95 mm, 7.32–7.95 mm, 5.25–5.35 mm, 8.60–8.75 mm, and 7.96–8.11 mm, 0.61–0.60, 196.72–205.28 mm2, and 210.00–270.00 kg m−3, respectively. The SHC, Tcd, and Tdf ranged from 0.14–0.52 J kg−1 K−1, 0.17–0.35 W m−1 K−1, and 0.10–0.20 m2 s−1, respectively. The ANOVA results indicated that the thermo‐physical properties studied were significantly (p ≤ 0.05) affected by moisture content. By utilizing the determined properties, engineers can develop efficient machines to harness the economic potential of sweetsop seed oil in various industries, including biofuel generation.Practical applicationsThe thermal and physical properties of sweetsop seed are needed by agricultural and mechanical engineers and food scientists to explore the potential application of the seed and the seed product, like oil for industrial and commercial purposes. Data obtained on the specific heat capacity of the seed would be valuable in designing of heating compartment of an oil expeller, thermal conductivity and diffusivity would be needed to design drying systems that balance efficiency and quality preservation, facilitate efficient removal of moisture from the seed while minimizing the risk of over‐drying or under‐drying. Thus, affects the design of the seed storage systems. Data on the seed axial dimensions, sphericity, mean diameters, surface area, and bulk density would be useful in the design and fabrication of agricultural equipment like sheller, grinder, packaging machines, discharge chute, aperture, and planter, to ensure proper seed placement, flow and to determine machine throughput capacity.

Investigation of Engineering Properties of Black Gram and Horse Gram for the Design of Hopper and Seed Plate of a Pneumatic Planter

Study presents an in-depth evaluation of the engineering properties of Black Gram (Vigna mungo) varieties VBN-6 and ADT-5, and Horse Gram (Macrotyloma uniflorum) varieties KS-2 and Paiyur-2. This is carried out for the design of a pneumatic seed metering unit viz., seed plate and the hopper. Emphasizing the importance of physical and engineering properties, the investigation on moisture content, axial dimensions, gravimetric properties, and key engineering characteristics such as density, porosity and frictional properties provides critical data for optimizing the design and functionality of the pneumatic seed metering unit, including the seed plate and hopper. For black gram, metering plates with 2.1 mm cell diameter were found optimal, whereas horse gram varieties require 3.5 mm diameter with 26 cells. Hopper of 9100 cm3 capacity made of mild steel of 2 mm thickness was developed according to the seed bulk density and flow characteristics. These properties made the pneumatic metering mechanism compatible with pulse seeds and helped to mechanize the pulse sowing.

Optical-resolution photoacoustic microelastography system for elasticity mapping: Phantom study and practical application.

Elastography is a noninvasive technique for characterizing the mechanical properties of biological tissues. Conventional methods have limitations in resolution and sensitivity, hindering disease detection in clinical diagnostics. To address these issues, this study developed an optical-resolution photoacoustic microelastography (OR-PAME) system. Using an agar tissue phantom with varying agar concentrations and contrast agents, PAME evaluated elasticity distribution under compression in both lateral and axial dimensions. It indirectly measured elastic properties by correlating photoacoustic responses, temporal lags, and induced displacement. We also applied the system to the study of the distribution of elastic characteristics of the liver tissue after ablation, which confirmed the potential of OR-PAME in the study of elastic characteristics. Quantitative analysis showed greater lateral displacement in regions with reduced agar concentrations, indicating decreased stiffness. PAME also detected vertical displacement along the axial plane, validating its efficacy in elastographic imaging. By improving resolution and penetration, PAME provides superior visualization of elasticity distribution. Its methodology correlates microstructural alterations with tissue biomechanics, holding potential implications in medical diagnostics.

Camera-based ultrasound-modulated optical tomography with isometric resolution

Ultrasound-modulated optical tomography (UOT) leverages the strengths of light and sound, enabling deep-tissue imaging with optical absorption contrast and acoustic resolution. Camera-based UOT, with its parallel detection capability, excels at handling weak light–sound interactions. However, the limited frame rate of the camera typically results in poor axial resolution and poses challenges for holographic measurements. In this study, we introduced intersected ultrasonic modulation to address these limitations, thereby achieving equal resolution in both lateral and axial dimensions through referenceless measurements. As a proof of concept, we constructed an imaging system and demonstrated two-dimensional imaging for absorptive targets buried inside a scattering medium. This approach opens avenues for improved imaging resolutions, showcasing the potential for future diagnostic endeavors.

Study on Physical Properties of Groundnut Cultivated in Andhra Pradesh for Design of Remote-Operated Groundnut Planter

Physical properties of groundnut seeds play an important role in designing the cell size of seed metering device, the thickness of metering disc, the diameter of metering device and the design of seed hopper for the development of remote-operated groundnut planter. The present study describes the measurement of the physical properties of four groundnut (Arachis hypogaea L.) varieties namely K-6 (Kadiri-6), Kadiri Lepakshi, Tag-24 (Trombay Akola Groundnut-24) and Dharani using standard measuring procedures. The results obtained for four varieties revealed that the seed length, width and thickness vary from 10.29 ± 1.11 to 17.52 ± 0.76 mm, 6.15 ± 0.39 to 9.51 ± 0.46 mm and 5.48 ± 0.33 to 8.59 ± 0.47 mm, respectively. The geometric mean diameter, arithmetic mean diameter and surface area varied from 7.39 ± 0.15 to 10.58 ± 0.36 mm, 7.87 ± 0.32 to 11.13 ± 0.45 mm, and 171.98 ± 6.89 to 352.21 ± 24.54 mm2, respectively. The Sphericity and Aspect Ratio varied from 55.51 ± 2.99 to 81.36 ± 6.87 % and 42.40 ± 4.16 to 77.82 ± 8.86 %, respectively. The Moisture Content (db.), bulk density, true density, porosity, hundred seeds weight and Angle of Repose for four different groundnut varieties are obtained as 5.25 to 10.45 %, 605.8 to 691.49 kg/m3, 1008.12 to 1123.4 kg/m3, 32.25 to 46.05 %, 30.485 to 45.62 g and 26.32 to 36.58º, respectively. The maximum values of axial dimensions were considered for design of seed metering device cell. The parameters of bulk density, test weight, and angle of repose were useful in the design of the seed hopper.

Electron trapping efficiency of a magnetron sputtering cathode

A common feature of all types of magnetron sputtering (MS) assemblies is an effective confinement of electrons by an appropriate combination of electric and magnetic fields. Therefore, studying the motions of electrons in the fields of magnetron assemblies is of particular importance. Here, we systematically analyze the electrons motions in front of a typical DC MS cathode. We first calculate the profiles of the magnetron’s magnetic field for balanced and two types of unbalanced configurations. Then, we compute the profiles of the cathode’s electric field before the gas discharge and after the plasma formation. A semi-analytical model is utilized to compute the plasma potential. We then track the motions of electrons released from the target and electrons produced through impact ionization of the background gas in the prescribed fields. A Monte Carlo model is implemented to consider electron-gas collisions and a mixed boundary condition is employed to account for electron-wall interactions. The study analyzes the impact of field profiles on the cathode’s efficiency in trapping electron by examining electron escape from the magnetic trap and electron recapture at the target surface. It is shown that the presence of plasma in all configurations leads to a significant increase in the trapping efficiency and the ionization performance, as well as a decrease in the recapture probability. These effects are attributed to the high electric field developed in the cathode sheath. Moreover, we statistically analyze the trapping efficiency by illustrating the spatial distributions of electrons locations in both axial and radial dimensions. It is demonstrated that during their azimuthal drift motion, the electrons released from the middle region at the target surface have the smallest range of axial and radial locations, in all configurations in the absence of plasma. Finally, the impact of field profiles on the average energies of electrons is discussed.

Design and optimization of a dual-port Helmholtz transducer for crosswell seismic survey

Given the limitations of conventional crosswell seismic sources, which struggle to reduce frequency by elongating the axial dimension of the transducer, this study introduces an innovative method for frequency reduction in such sources. The proposed approach entails adding metal end caps with orifices to the piezoelectric circular tube with both ends open. This modification transforms the originally cylindrical liquid cavity with both ends open into a dual-port Helmholtz liquid cavity. To begin with, the frequency reduction effect of the dual-port Helmholtz liquid cavity is theoretically demonstrated using the equivalent circuit method. Subsequently, the finite element method is employed to validate the accuracy of the equivalent circuit and to compare the radiation performance of the two transducer models. Further, the impact of the materials and structural parameters of end caps on the resonant frequency of the liquid cavity is investigated using the finite element method. Finally, four transducer prototypes are fabricated, and their conductance curves are tested in silicone oil to verify the feasibility of the proposed approach. The test results affirm that the dual-port Helmholtz transducer exhibits a lower resonant frequency of the liquid cavity, which aligns well with the simulation results. The proposed dual-port Helmholtz transducer offers a promising solution for achieving low-frequency emission in crosswell seismic sources. The research findings establish a solid theoretical foundation for the design and optimization of this transducer.

Three-dimensional Spinal Canal Morphometric Analysis and Relevant Spinal Cord Occupational Ratios in Congenital Cervical Spinal Stenosis: A Classification Algorithm of the Stenosis Phenotypes and Data-driven Decompression Approach

No standardized magnetic resonance imaging (MRI) parameters have defined the 3-dimensional morphoanatomy and relevant spinal cord occupation ratios (occupation of spinal cord dimensions/similar dimensions within the spinal canal) in congenital cervical stenosis (CCS). A retrospective, comparative analysis was conducted on 200 patients >18 years of age with myelopathy and CCS (mean age, 52.4 years) and 200 age-matched controls with no myelopathy or radiculopathy. The variables assessed from high resolution MRI included sagittal and axial spinal canal dimensions (MRI Torg-Pavlov ratios) from C3 to C7. Morphometric dimensions from the sagittal retrodiscal and retrovertebral regions as well as axial MRI dimensions were compared. Sagittal and axial spinal cord occupation ratios were defined and correlated with spinal canal dimensions. Multivariate analyses indicated reduced sagittal and axial anteroposterior (AP) spinal canal dimensions and a large reduction in transverse spinal canal dimensions at all spinal levels. There was a small significant correlation between AP sagittal spinal canal dimensions and axial transverse spinal canal dimensions at C3-C5, but not at C5-C6. Small correlations were noted between AP sagittal spinal canal dimensions and AP axial spinal cord and axial cross-sectional area occupation ratios at C3-C6, but there was no correlation with axial mediolateral spinal cord occupation ratios. The stenosis effect can involve any dimension, including the transverse spinal canal dimension, independent of other dimensions. Owing to the varied observed morphoanatomies, a classification algorithm that defines CCS specific phenotypes was formulated. Objectivizing the stenosis morphoanatomy may allow for data-driven patient-focused decompression approaches in the future.

Research on Energy Loss of Optimization of Inducer–Impeller Axial Fit Dimensions Based on Wave-Piercing Theory

With the development of modern fluid machinery, the energy density of pumps is gradually being improved, and at the same time, higher demands are being placed on the cavitation performance, hence the introduction of the inducer and centrifugal impeller to form a dynamic–dynamic series structure. However, there are strict constraints on the axial size of pumps in fields such as firefighting and aerospace. The traditional empirical formula no longer satisfies the need to fit the axial dimensions between the induced wheel and the impeller at high velocities. Therefore, based on the wave-piercing theory, the drag reduction coefficient is introduced to explore the optimal axial fit size from the perspective of energy characteristics. This paper focuses on the influence of the inducer’s wake on the energy characteristics of downstream impellers, and conducts the following research: by adjusting the axial matching dimensions between the upstream inducer and the centrifugal impeller in the initial model, ten sets of axial distance models with matching dimensions of KD are designed, and the drag reduction coefficient is embedded to determine the optimal axial distance. The results show that the optimal axial distance is 0.2D, which is far lower than the axial distance value of 0.42D obtained from the traditional empirical formula for axial matching dimensions. Meanwhile, this paper uses tangential velocity, the inlet flow angle of the impeller, entropy production theory, and other indicators to analyze the internal energy loss of the high-speed vehicular fire pumps one by one. All of them confirm that the impeller in the high-speed vehicular fire pump has the lowest energy loss and optimal performance at an axial distance of 0.2D. Specifically, at this axial distance, the head can reach 259 m, and the hydraulic efficiency is as high as 83.62%. Thus, the feasibility of determining the axial placement of the impeller using the drag coefficient is validated. This research provides new insights into determining the axial coordination dimensions between the inducer and the impeller.

Optimal speckle size and signal processing for displacement measurements using a 4f optical setup

Fully developed laser speckle patterns are, due to their high contrast and statistical nature, well suited to measure strain and displacement via an appropriately designed measurement system. Laser speckle patterns are formed when a sufficiently coherent light source, such as a HeNe-laser, illuminates an optically rough surface. Therefore, methods based on laser speckle patterns can be applied to any surface scatterer with a minimum mean surface roughness of about a quarter of the laser’s wavelength. This includes also materials such as thin natural and technical fibres as well as foils, for which the presented measurement system, including the digital signal processing, was designed. In order to achieve the best possible resolution of a speckle-based measurement system, combined with a sufficiently small measurement uncertainty, all available design parameters must be optimised. One of these parameters is the speckle size, which is dependant on the properties of the imaging optics. In this paper a subjective laser speckle-based measurement system based on a so-called 4f-optical setup is presented. This setup allows the speckle size to be controlled in both axial and lateral dimensions separately, which is achieved with the help of an aperture in the Fourier plane of the optics. It is shown that the optimal speckle size for the presented measurement system, not only depends on the physical setup, but also on the signal processing applied. The signal processing routine estimates displacements of the speckle pattern, leading to an estimate for the strain. Additionally, it is demonstrated that the optimal speckle size can be lower than the commonly reported optimum between two and five pixel pitches, necessary to circumvent aliasing in the image data. While this is shown for a measurement setup using 4f-optics, the results are of general importance to speckle-based strain or displacement measurement systems and should thus be taken into account.

Resection of colorectal carcinoma liver metastases: A population-based study in outcomes and factors associated with recurrent disease

ObjectiveTo assess the hepatic disease-free survival (HDFS) and overall survival (OS) of patients who underwent resection of colorectal cancer liver metastases (CRCLM) in our population, and evaluate what factors are associated with these outcomes. MethodsPatients with resected non-mucinous CRCLM between January 2013-February 2020 were retrospectively identified. Dates of diagnosis, surgery, and, if applicable, death were recorded. HDFS and OS were calculated using a census date of 24 September 2022. Separate Cox multivariate regression analyses were performed to evaluate for association between HDFS and OS and the following factors: pre-operative imaging interval (<4 weeks vs. ≥4 weeks); pre-operative imaging modality (CT only vs. MRI+CT); extrahepatic disease at time of hepatectomy (yes vs. no); tumor burden score (TBS, where TBS2 = (largest axial dimension of CRCLM)2 + (number of CRCLM)2); pT and pN; and neoadjuvant chemotherapy. Results137 subjects (mean age, 61 ± 11 years, 86 males) were included. Associations with recurrent hepatic disease were found with chemotherapy (HR 2.11[95 % CI = 1.13–3.92]), TBS (HR 1.30[95 % CI = 1.17–1.45]), MRI+CT (HR 2.12[95 % CI = 1.29–3.48]), and extrahepatic disease at hepatectomy (HR 2.16[95 % CI = 1.08–4.35]). For mortality, associations were found with TBS (HR 1.22[95 % CI = 1.09–1.37]), pT (HR 1.45[95 % CI = 1.05–2.00]), and extrahepatic disease at hepatectomy (HR 2.10[95 % CI = 1.31–3.36]). ConclusionIn our population, non-imaging related factors TBS, neoadjuvant chemotherapy, pT and presence of extrahepatic disease at time of hepatectomy were associated with HDFS and/or OS. The preoperative imaging interval and use of preoperative MRI were not associated with improved patient outcomes.

Depth-dependent scaling of axial distances in light microscopy

In volume fluorescence microscopy, refractive index matching is essential to minimize aberrations. There are, however, common imaging scenarios where a refractive index mismatch (RIM) between immersion and a sample medium cannot be avoided. This RIM leads to an axial deformation in the acquired image data. Over the years, different axial scaling factors have been proposed to correct for this deformation. While some reports have suggested a depth-dependent axial deformation, so far none of the scaling theories has accounted for a depth-dependent, non-linear scaling. Here, we derive an analytical theory based on determining the leading constructive interference band in the objective lens pupil under RIM. We then use this to calculate a depth-dependent re-scaling factor as a function of the numerical aperture (NA), the refractive indices n1 and n2, and the wavelength λ. We compare our theoretical results with wave-optics calculations and experimental results obtained using a measurement scheme for different values of NA and RIM. As a benchmark, we recorded multiple datasets in different RIM conditions, and corrected these using our depth-dependent axial scaling theory. Finally, we present an online web applet that visualizes the depth-dependent axial re-scaling for specific optical setups. In addition, we provide software that will help microscopists to correctly re-scale the axial dimension in their imaging data when working under RIM.